A method of controlling data sampling clocking of asynchronous network nodes, each asynchronous network node having a local clock and transmitting and receiving packets to and from an asynchronous network according to an asynchronous network media access protocol. An asynchronous network node capable of transmitting and receiving packets on the asynchronous network is designated as a master node. Each non-master asynchronous network node which desires to synchronously transport packets across the asynchronous network is designated as a slave node. A master node clock of the master node is synchronized with a slave node clock of each slave node. Each slave node clock is continuously corrected compared with the master node clock to smooth slave clock error to an average of zero compared with the master clock as a reference using timestamp information from the master node. A derivative clock at the slave node is derived from the continuously correcting each slave node clock to control data sampling at the slave node.

The present invention relates to the field of communications, and, in particular, a frame-based communications network for providing voice services utilizing a non-synchronous shared medium LAN integrated with a gateway to a synchronous network.
As computers become more and more cost effective for the everyday consumer and for small businesses, such computers become more plentiful for use within local area environments such as homes, office buildings and the like. For example, within a home a person with a computer in the bedroom, and another in the living room, may want to share common files, utilize a common digital subscriber line (DSL), or otherwise transfer information between the computers. Accordingly, various technologies are being developed for computer interconnection of multiple computers located within such environments. One example of such technologies are the Home Phoneline Network Alliance (HPNA) specifications for local area network (LAN) computer interconnection which utilize existing telephone lines within the local environment for the transmission of data packets between the computers.
FIG. 1a shows in block diagram form a general home networking environment within which the present invention can be implemented. Home network 10 includes existing (installed) plain old telephone service (POTS) wiring 12, network clients 14, the computer port side of modem 16 and fax 18. POTS wiring 12 provides wiring infrastructure used to network multiple clients at a customer premises (e.g., home) 20. POTS wiring 12 can be conventional unshielded twisted pair (UTP) wiring that is generally routed internally in the walls of the customer premises 20 to various locations (e.g., rooms) within the customer premises. Subscriber loop 22 (also called a "local loop") is a physical wiring link that directly connects an individual customer premises 20 to the Central Office through telephone network interface 24, a demarcation point between the inside and outside of customer premises 20. Of particular importance for residential networks are systems that provide communication between computers as reliably and with as high a data rate as possible. Communication over residential telephone wiring is provided through inventive frame-oriented link, media access and physical layer protocols and implementation techniques associated therewith described herein.
Referring now to FIG. 1b, those skilled in the art can appreciate that home phone-line network configuration 10 can also utilize interface 6010 to provide signals outside customer premises 20. For example, interface 6010 can include a V.90 modem as described above, connected through the central office to an internet service provider. Interface 6010 can include an ADSL modem, a VDSL modem or the like transport interface.
Another desired solution for high speed data communications appears to be cable modem systems. Cable modems are capable of providing data rates as high as 56 Mbps, and is thus suitable for high speed file transfer. In a cable modem system, a headend or cable modem termination system (CMTS) is typically located at a cable company facility and functions as a modem which services a large number subscribers. Each subscriber has a cable modem (CM). Thus, the CMTS facilitates bidirectional communication with any desired one of the plurality of CMs. Referring to FIG. 1c, a hybrid fiber coaxial (HFC) network 1010 facilitates the transmission of data between a headend 1012, which includes at least one CMTS, and a plurality of homes 1014, each of which contains a CM. Such HFC networks are commonly utilized by cable providers to provide Internet access, cable television, pay-per-view and the like to subscribers. Approximately 500 homes 1014 are in electrical communication with each node 1016, 1034 of the HFC network 1010, typically via coaxial cable 1029, 1030, 1031. Amplifiers 1015 facilitate the electrical connection of the more distant homes 1014 to the nodes 1016, 1034 by boosting the electrical signals so as to desirably enhance the signal-to-noise ratio of such communications and by then transmitting the electrical signals over coaxial conductors 1030, 1031. Coaxial conductors 1029 electrically interconnect the homes 1014 with the coaxial conductors 1030, 1031, which extend between amplifiers 1015 and nodes 1016, 1034. Each node 1016, 1034 is electrically connected to a hub 1022, 1024, typically via an optical fiber 1028, 1032. The hubs 1022, 1024 are in communication with the headend 1012, via optical fiber 1020, 1026. Each hub is typically capable of facilitating communication with approximately 20,000 homes 1014. The optical fiber 1020, 1026 extending intermediate the headend 1012 and each hub 1022, 1024 defines a fiber ring which is typically capable of facilitating communication between approximately 100,000 homes 1014 and the headend 1012. The headend 1012 may include video servers, satellite receivers, video modulators, telephone switches and/or Internet routers 1018, as well as the CMTS. The headend 1012 communicates via transmission line 1013, which may be a T1 or T2 line, with the Internet, other headends and/or any other desired device(s) or network.
Given the HPNA environment and the Cable Modem System environment, an opportunity exists for a system provider to integrate each respective environment with voice services. FIG. 1d depicts such an integrated environment. As can be seen in FIG. 1d, a connection point in the home to the telephony world (e.g., the world of video, voice, high speed data network traffic), could be provided to a home user through cable modem 1046 which would include an HPNA transceiver. The cable modem system provider may also wish to accomodate providing telephone service along with high speed data service. A home computer user, rather than using a traditional modem to connect to an internet service provider, would find it convenient to utilize cable modem 1046, taking advantage of the very high speed data service provided by the cable modem. Having a cable modem customer, the cable modem provider may also find it commercially beneficial to offer video feeds, and telephone service over the same cable modem network.
A cable modem having an HPNA V2 transceiver included therein, can readily interface into the home phone line network through the telephone jack within the home. Computers coupled to the home network could then communicate through the cable modem to the outside telephony world as described above. However, telephone service coming from outside the customer premises over the cable modem system would be in a digitized packetized format. It would then proceed over the HPNA network in the same digitized packeting format. If the user, in addition to having computers and the like attached to the HPNA network, wished to have an analog telephone(s) connected to the HPNA, the telephone' (s) analog signal could go through a digital conversion and put the digital information into packets for passing the packets back and forth over the network. The analog telephone signal would need to be sampled and packetized at the appropriate clock rate creating the packet after a certain number of samples. In such an implementation, a mechanism would be needed to discover the timing of the cable modem system and to synchronize the conveyance of information between the telephone, the HPNA network, and the cable modem. Therefore, solutions are needed to deal with voice service issues which may arise in such an integrated Home Phone Line/Cable Modem System environment. The present invention provides such a solution.
In accordance with the present invention, as indicated above, a need exists to effectively deliver voice traffic on the Homenetworking (HPNA V2) network. Of note is the need to get the voice traffic to operate within performance goals within the HPNA V2 network. In particular, issues dealing with an A/D converter sampling circuit clock synchronization on the home network, and issues dealing with packet boundaries and when to take a set of samples and call it a packet for use on the home network, need resolution.
Consider the application of voice data in conjunction with the home network, in general. How data is packaged and how higher layer information is communicated are issues which need to be addressed. When the home has a connection point (e.g., a gateway) to the public telephony systems, video/voice high speed data networks, and a phone service provider wishes to supply phone service along with high speed data, one technique is to provide a cable modem instead of having a traditional modem for connection to an internet service provider (ISP). With the cable modem, a computer can be connected thereto to allow the user to have a very high speed data service. The high speed data service provider may also wish to provide video feeds, phone service over the same network. The cable modem could also contain connection points to allow the phones in the home to be connected to the cable modem, that is, the analog phone signal goes into the cable modem and gets converted to appropriate digital signals for transmission from the cable modem to the public telephony network. U.S. patent application Ser. No. 09/501,850 entitled "Cable Modem System with Sample and Packet Synchronization", owned by the Assignee of the present application and incorporated herein by reference, describes such a system. When the HPNA V2 system is also employed in the home to provide local area network interconnection for the transfer of digital data, such HPNA system can be connected to the cable modem. In turn, if the analog phone were to be connected to the HPNA V2 system, it cannot be directly attached to the HPNA V2 system. The analog phone signal must go through a digital conversion and be put into packets for passage over the digital-based HPNA V2 and the cable modem systems, i.e., when the cable modem system is connected to the HPNA V2 system, telephone service coming over the cable system is in digitized packetized format. When the telephone is attached to the HPNA V2 network, the telephone can have an HPNA V2 transceiver located therewithin or coupled between the telephone and the HPNA line via a converter. However, when taking the telephone signal and packetizing it at the appropriate clock rate and creating a packet after a certain number of samples to synchronize with the cable modem system network, since the telephone is not directly attached to the cable modem system network, a solution is needed to discover the appropriate timing and process the signals to allow proper synchronization with the cable modem system network. The present invention provides such a solution.

Method of controlling data sampling clocking of asynchronous network nodes in a frame-based communications network


A seaming device for connecting building panels in a continuous along adjacent side edges of two building panels in the construction of a building or light structure which is particularly suited for seaming panels with both curved and straight portions. The seaming device includes a first frame having an electric motor and two horizontally opposed rollers and a second portion having an electric motor and two horizontally opposed rollers with the first and second portions being coupled together in a hinge-like manner.

1. Field of the Invention
The invention relates to a novel seam-forming apparatus for connecting building panels in a continuous seam along adjacent side edges of two building panels in the construction of a building or like structure.
2. Prior Art and Background
It is known to construct continuous arch metal buildings with adjacent curved building panels which are seamed together at their adjacent edges. Such a system is described, for example, in U.S. Pat. No. 4,505,084 and U.S. Pat. No. 5,249,445.
In connection with seaming panels for such metal buildings, seaming devices have been used. Such a device is disclosed, for example, in U.S. Pat. No. 4,470,186 which is hereby incorporated by reference as if fully set forth herein. The seaming device connects or seams together the side edge portions of adjacent panels.
An apparatus referred to as a panel machine produces structural panel members using a roll forming process such as described in U.S. Pat. No. 4,505,084. Incorporated in one edge of each panel is a hook portion and on the opposite edge is a hem portion. The hem portion is designed to fit underneath and inside of the hook portion of an adjacent panel resulting in an interlocking feature for joining the panels together. The panels themselves may be curved or straight and may have both straight and curved portions.
Past seamers have usually only been capable of seaming either straight panel portions or curved panel portions. Such seamers are not able to seam panels that are both straight and curved. When attempting to utilize such a seamer on panels with both curved and straight portions, the seaming apparatus tends to "walk off" or dislodge from the seam particularly in transition areas where the panel changes from straight to curved or vice versa. In addition, such seamers were prone to cause damage to the panel and the finish of the panel, particularly in the transition regions.

Seaming device capable of joining curved and straight panels


Improving the flow of hydrocarbons from shale lateral wellbores in unconventional wellbores may be accomplished with various configurations of assisting lateral wellbores and/or kick-off wellbores from primary lateral wellbores and/or secondary or assisting lateral wellbores. By extending fracture networks from adjacent lateral wellbores and/or adjacent kick-off wellbores so that the fracture networks from different wellbores are in fluid communication with one another, the flow of various fluids between the adjacent wellbores provides another dimension of control over the wellbores and fracture networks used to recover hydrocarbons from the shale intervals of interest.

It is well known that hydrocarbons (e.g. crude oil and natural gas) are recovered from subterranean formations by drilling a wellbore into the subterranean reservoirs where the hydrocarbons reside, and using the natural pressure of the hydrocarbon or other lift mechanism such as pumping, gas lift, electric submersible pumps (ESP) or another mechanism or principle to produce the hydrocarbons from the reservoir. Conventionally most hydrocarbon production is accomplished using a single wellbore. However, techniques have been developed using multiple wellbores, such as the secondary recovery technique of water flooding, where water is injected into the reservoir to displace oil. The water from injection wells physically sweeps the displaced oil to adjacent production wells. Potential problems associated with water flooding techniques include inefficient recovery due to variable permeability or similar conditions affecting fluid transport within the reservoir. Early breakthrough is a phenomenon that may cause production and surface processing problems.
Hydraulic fracturing is the fracturing of subterranean rock by a pressurized liquid, which is typically water mixed with a proppant (often sand) and chemicals. The fracturing fluid is injected at high pressure into a wellbore to create, in shale for example, a network of fractures in the deep rock formations to allow hydrocarbons to migrate to the well. When the hydraulic pressure is removed from the well, the proppants, e.g. sand, aluminum oxide, etc., hold open the fractures once fracture closure occurs. In one non-limiting embodiment chemicals are added to increase the fluid flow and reduce friction to give "slickwater" which may be used as a lower-friction-pressure placement fluid. Alternatively in different non-restricting versions, the viscosity of the fracturing fluid is increased by the addition of polymers, such as crosslinked or uncrosslinked polysaccharides (e.g. guar gum) or by the addition of viscoelastic surfactants (VES).
Recently the combination of directional drilling and hydraulic fracturing has made it economically possible to produce oil and gas from new and previously unexploited ultra-low permeability hydrocarbon bearing lithologies (such as shale) by placing the wellbore laterally so that more of the wellbore, and the series of hydraulic fracturing networks extending therefrom, is present in the production zone permitting more production of hydrocarbons as compared with a vertically oriented well that occupies a relatively small amount of the production zone. "Laterally" is defined herein as a deviated wellbore away from a more conventional vertical wellbore by directional drilling so that the wellbore can follow the oil-bearing strata that are oriented in a non-vertical plane or configuration. In one non-limiting embodiment, a lateral wellbore is any non-vertical wellbore. In another non-limiting embodiment, a lateral wellbore is defined as any wellbore that is at an inclination angle from vertical ranging from about 45° to about 135°. It will be understood that all wellbores begin with a vertically directed hole into the earth, which is then deviated from vertical by directional drilling such as by using whipstocks, downhole motors and the like. A wellbore that begins vertically and then is diverted into a generally horizontal direction may be said to have a "heel" at the curve or turn where the wellbore changes direction and a "toe" where the wellbore terminates at the end of the lateral or deviated wellbore portion. The "sweet-spot" of the hydrocarbon bearing reservoir is an informal term for a desirable target location or area within an unconventional reservoir or play that represents the best production or potential production. The combination of directional drilling and hydraulic fracturing has led to the so-called "fracking boom" of rapidly expanding oil and gas extraction in the US beginning in about 2003.
Improvements are always needed in the driller's ability to find and map sweet-spots to enable wellbores to be placed in the most productive areas of the reservoirs. Sweet-spots in shale reservoirs may be defined by the source rock richness or thickness, by natural fractures present therein or by other factors. Conventionally, geological data, e.g. core analysis, well log data, seismic data and combinations of these are used to identify sweet-spots in unconventional plays.

Placement and uses of lateral assisting wellbores and/or kick-off wellbores


A method of processing sequential frames of data comprises repeating the following steps for successive frames of data: acquiring at least a reference frame containing data points and a current frame of data points; identifying a set of anchor points in the reference frame; assigning to each anchor point in the reference frame a respective motion vector that estimates the location of the anchor point in the current frame; defining polygons formed of anchor points in the reference frame, each polygon containing data points in the reference frame, each polygon and each data point contained within the polygon having a predicted location in the current frame based on the motion vectors assigned to anchor points in the polygon; for one or more polygons in the reference frame, adjusting the number of anchor points in the reference frame based on accuracy of the predicted locations of data points in the current frame; and if the number of anchor points is increased by addition of new anchor points, then assigning motion vectors to the new anchor points that estimate the location of the anchor points in the current frame.

The recent advance in the field of communication-based applications such as videophone and video conferencing systems mainly concentrate on minimizing the size and the cost of the coding equipment. The low cost of the final product is the most essential part of the current age of technology. Most current real-time systems include video applications that need to process huge amounts of data and large communication bandwidth. Real-time video applications include strategies to compress the data into a feasible size.
Among different data compression techniques, object-based video representation, as addressed by MPEG-4, allows for content-based authoring, coding, distribution, search and manipulation of video data. In MPEG-4, the Video Object (VO) refers to spatio-temporal data pertinent to a semantically meaningful part of the video. A 2-D snapshot of a Video Object is referred to as a Video Object Plan (VOP). The 2-D triangular mesh is designed on the first appearance of VOP as extension for the 3D modeling. The vertices of the triangular patches are referred to as the nodes. The nodes of the initial mesh are then tracked from VOP to VOP. Therefore, the motion vectors of the node points in the mesh represent the 2D motion of each VO. The motion compensation is achieved by triangle wrapping from VOP to VOP using Affine transform.
Recently, hierarchical mesh representation attracted attention because it provides rendering at various levels of detail. It also allows scalable/progressive transmission of the mesh geometry and motion vectors. The hierarchical mesh coding is used for transmission scalability where we can code the mesh at different resolutions to satisfy the bandwidth constraints and/or the QoS requirements.
Hierarchical 2D-mesh based modeling of video sources has been previously addressed for the case of uniform topology only. The mesh is defined for coarse-to-fine hierarchy, which was trivially achieved by subdividing each triangle/quadrangle into three or four subtriangles or quadrangles, as in C. L. Huang and C.-Y. Hsu, "A new motion compensation method for image sequence coding using hierarchical grid interpolation:" IEEE Trans. Circuits. Syst Video Technol., vol 4, pp. 42-51, February 1994.
A basic requirement of active tracking system is the ability to fixate or track video objects using an active camera. Real-time object tracking systems have been developed recently. T. Darrel's system combines stereo, color, and face detection modules into a single robust system. Pfinder (person finder) uses a multi-class statistical model of color and shape to obtain a 2-D representation of head and hands in a wide range of viewing conditions. KidRooms is a tracking system based on closed-world regions, where regions of space and time in which the specific context of what is in the regions is assumed to be known. These regions are tracked in real-time domains where object motions are not smooth or rigid, and where multiple objects are interacting. Multivariate Gaussian models are applied to find the most likely match of human subjects between consecutive frames taken by cameras mounted in various locations. Lipton's system extracts moving targets from a real-time video stream, classifies them into pre-defined categories and tracks them. Because it uses correlation matching, it is primarily targeted at the tracking of rigid objects. Birchfield proposed an algorithm for tracking a person's head by modeling the head as an ellipse whose position and size are continually updated by a local search combining the output of a module concentrating on the intensity gradient around the ellipse's perimeter, and another module focusing on the color histogram of the ellipse's interior. Reid and Murry introduced monocular fixation using affine transfer as a way of a cluster of such features, while at the same time respecting the transient nature of the individual features.
Mesh based frame processing is disclosed and discussed in papers by Badawy, one of the inventors of this invention, in "A low power VLSI architecture for mesh-based video motion tracking" Badawy, W.; Bayoumi, M. A. IEEE Transactions on Circuits and Systems II: Analog and Digital Signal Processing, Volume 49, Issue 7, pp 488-504, July 2002; and also in "On Minimizing Hierarchical Mesh Coding Overhead: (HASM) Hierarchical Adaptive Structured Mesh Approach", Badawy, W., and Bayoumi, M., Proc. IEEE Int. Conf. Acoustics, Speech and Signal Processing, Istanbul, Turkey, June 2000, p. 1923-1926; and "Algorithm Based Low Power VLSI Architecture for 2-D mesh Video-Object Motion Tracking", IEEE Transactions on Circuits and Systems for Video Technology, vol. 12, no. 4, April 2002. The present invention is directed towards an improvement over the technology disclosed in Badawy papers.
Coding of frame data requires a motion detection kernel. Perhaps, the most popular motion estimation kernel used for inter-frame video compression is the block matching model. This model is often more preferred over others in video codec implementations, because it does not involve complicated arithmetic operations as compared to other kernels such as the optical flow model. However, the block matching model has major limitations in the accuracy of estimated motion, since it only allows inter-frame dynamics to be described as a series of block translations. As a result, any inter-frame dynamics related to the reshaping of video objects will be inaccurately represented.
The mesh-based motion analysis as disclosed by Badawy addresses the shortcomings of block matching. In this model, an affine transform procedure is used to describe inter-frame dynamics, so that the reshaping of objects between video frames can be accounted for and the accuracy of estimated motion can be improved. Since this model also does not require the use of complicated arithmetic procedures, it has attracted many developers to use it as a replacement for the block matching model in inter-frame codec implementations. Indeed, MPEG-4 has included the mesh-based motion analysis model as part of its standard.
The efficacy of the mesh-based motion analysis model, even with the improvements disclosed in this patent document, is often limited by the domain disparity between the affine transform function and the pel domain. In particular, since the affine transform is a continuous mapping function while the pel domain is discrete in nature, a discretization error will result when the affine transform is applied to the pel domain. As pel values are not uniformly distributed in a video frame, a minor discretization error may lead to totally incorrect pel value mappings. Hence, the quality of frames reconstructed by the mesh-based motion analysis model is often affected. The poor frame reconstruction quality problem becomes even more prominent at the latter frames of a group-of-pictures (GOP), since these latter frames are reconstructed with earlier reconstructed frames in the same GOP and thus all prior losses in the frame reconstruction quality are carried over.
To resolve the frame reconstruction quality problem in the mesh-based motion analysis model, residual coding techniques can be employed. These techniques provide Discrete Cosine Transform (DCT) encoding of the prediction difference between the original frame and the reconstructed frame, and thus better frame reconstruction quality can be achieved. However, the use of these techniques will reduce the compression efficiency of the video sequence, since residual coding will bring about a significant increase in the compressed data stream size. To this end, residual coding via the matching pursuit technique may be used instead. This approach offers high quality residual coding with very short amendments to the compressed data stream. Nevertheless, it is not a feasible coding solution as yet because of its high computational power requirements.

Mesh based frame processing and applications


A brewing unit includes a brewing chamber with first and second brewing chamber portions movable one with respect to the other, and a water heater. Further, the brewing unit includes a structural frame supporting the two brewing chamber portions, and on which forces generated by the pressurized water in the brewing chamber during brewing are discharged. The structural frame includes two side components arranged sideways of the brewing chamber, and two end components mechanically constrained to the side components. One of the two end components includes the first brewing chamber portion. Further, the side components and the end components form a closed structure, whereto the water heater is in turn constrained independently, with separate constraining members, from the first brewing chamber portion and adjacent thereto, outside the closed structure. The forces generated by the pressurized water in the brewing chamber during brewing are also discharged on the water heater.

For producing hot drinks, such as for example coffee, tea, vegetable-based infusions and the like, single-dose packagings, in the form of so-called capsules, pods, cartridges or the like are often used. Here after the term "capsule" will be used to broadly designate such a single-dose packaging. It shall be understood that, unless specifically indicated, said term is to be understood as encompassing any kind of single-dose packaging suitable for preparing beverages or other edible products by extraction using hot and possibly pressurized water. A single dose packaging can include sufficient ingredients to prepare more than just one portion of beverage, e.g. two portions.
Capsules usually contain the ingredients for producing the drink. Hot water is made to flow through the capsule at an adequate pressure to extract the flavours from the ingredients contained in the capsule. There are several types of devices for handling the capsules and for the infusion, that is phase of extracting the flavours from the capsules through water passage.
Some coffee machines are designed for use of loose coffee powder or other loose products. In these machines a dosed quantity of loose product is charged in a brewing chamber. The chamber is closed in a water-tight manner and hot pressurized water is fed from a water heater through the product charged in the brewing chamber, to extract flavours from the ingredients.
U.S. Pat. No. 6,129,006 and EP-A-0931491 disclose a brewing unit specifically intended for brewing coffee from bulk coffee powder. This known brewing unit includes a brewing chamber and a water heater. The water heater is arranged near to the brewing chamber.
Arranging the water heater near the brewing chamber has the advantage of reducing heat dissipation from the heated water along the path from the water heater to the brewing chamber.
One problem of these brewing units, being of the type using pre-packaged single-dose capsules, or loose ingredients, is connected with the need of providing a structure surrounding the brewing chamber which is capable of resisting high mechanical stresses generated by the pressurized water fed through the brewing chamber. For the preparation of espresso coffee, for example, water pressurized up to 8-15 bar flows through the brewing chamber. The force exerted by the water against the portions of the brewing chamber must be supported by a suitably designed frame on which the brewing chamber is mounted. This requires cumbersome structures.


An information processing method and an electronic apparatus are disclosed. The method is applicable to the electronic apparatus. The method includes: detecting, with a touch display unit of the electronic apparatus, a first trajectory generated by a first input operation of an input unit; acquiring motion parameters of the input unit collected by a sensing unit in a case that it is determined that the first trajectory meets a predetermined condition; and using the motion parameters to correct the first trajectory in accordance with a first correction strategy.

Electronic apparatuses are increasingly diversified as technology advances. In a technology, an electronic apparatus can convert words written on a touch display unit of the electronic apparatus by an input unit into an electronic document, where the input unit may be a stylus.
In a specific application, in a case that a user writes too fast on the electronic apparatus by using the input unit, the system of the electronic apparatus is unable to respond in a timely manner, thereby causing that a recognized writing trajectory has a breakpoint or is illegible, which affects the appearance of the writing trajectory, and is inconvenient for the user to view the writing trajectory.
This problem can not be solved yet in the conventional technology.

Information processing method and electronic apparatus


A microwave reactor for decomposing waste green house gases resulting from the manufacture of semiconductors and from other industrial processes. The microwave reactor includes a plasma chamber having a gas inflow port spaced apart from a gas outflow port for transporting gases through the plasma chamber. A gas plasma is generated in the plasma chamber to facilitate the gas decomposition. The structure of the microwave reactor includes an insulating cover protruding into the plasma chamber and forming an internal cavity that is isolated from gases in the plasma chamber. A microwave antenna extends into the internal cavity of the plasma chamber to couple the microwave energy into plasma chamber for causing a plasma to form in the gases.

PROCESS GAS DECOMPOSITION REACTOR, invented by Bruce Minaee, filed May 17, 2000 and having SC/Ser. No: 09/572,111.
The present invention relates to the field of gas decomposition and, more particularly, to a microwave reactor for decomposing waste gases resulting from the manufacture of semiconductors and from other industrial processes.
Certain gases such as Perfluorinated Compounds (PFCs) including nitrogen trifloride, NF3, and sulfurhexafloride, SF6, and hydrofluorocarbons (HFCs) emitted by industrial processes, such as semiconductor processes, are harmful when released into the atmosphere. PFCs and HFCs are categorized as greenhouse gases because of their strong infrared absorption and long atmospheric lifetimes. PFCs and HFCs act similar to CO2 in causing the greenhouse effect. Because of their potential long term impact on the global climate, PFC""s, HFC""s, NF3 and SF6 have been included in the Kyoto Protocol which is aimed at significantly reducing the release of unwanted gases into the atmosphere.
The above-identified, cross-referenced application PROCESS GAS DECOMPOSITION REACTOR describes an improved microwave reactor for removing unwanted gases from industrial processes. In the cross-referenced application, a microwave reactor generates a plasma for decomposition of perfluorinated and hydro fluorocarbon compounds in a gas stream emerging from an industrial process, for example, a semiconductor manufacturing process. The reactor features a pair of magnetrons feeding a pair of launching waveguides to a pair of helical coils forming a microwave induction structure within a plasma chamber coaxial with the gas flow path.
In the cross-referenced application, the plasma chamber includes inlet and outlet openings through which reactant and additive gases (such as oxygen, hydrogen or water vapor) enter the chamber and exit the chamber for gas flow-through processing. The openings of the plasma chamber are through flanges which mate with corresponding flanges in exhaust gas lines from the industrial process apparatus. The gases enter the plasma microwave chamber through a standard vacuum flange, are dispersed, and undergo plasma decomposition reactions in the microwave chamber. The decomposition reactions result in hydrofluorocarbonated compounds and perfluorocarbonated compounds and these and other exhaust gases are evacuated from the plasma chamber through directly mounted flanges at the outlet of the plasma chamber.
In the cross-referenced application, decomposition reactions occur once the microwave chamber has been energized to cause a plasma and the reactant and additive gases are flowing. A microwave generated field causes ionization of the gas molecules by extracting electrons from them. These electrons are accelerated by the microwave generated field and cause more ionization and cracking of the gas molecules. The cracked reactant molecules and the cracked additive gas molecules react to form by-products that can be scrubbed by a wet scrubber.
While the cross-referenced application is a significant improvement over other gas reactors, the embodiments described are constrained by the ability to economically generate microwave-induced plasmas without excessive wear on the microwave components. As semiconductor processes use larger and larger gas-flow tubes for larger and larger semiconductor wafers and other parts, a need exists for larger, more efficient and more easily installed and maintained microwave reactors for removing unwanted gases.
Accordingly, there is a need for improved microwave reactors to decompose PFCs, HFCs and other unwanted gases suitable for insertion in the lines of processes used in industry, particularly in the semiconductor manufacturing industry.
The present invention is a microwave reactor for decomposing waste green house gases resulting from the manufacture of semiconductors and from other industrial. The microwave reactor includes a plasma chamber having a gas inflow port spaced apart from a gas outflow port for transporting gases through the plasma chamber. A gas plasma is generated in the plasma chamber to facilitate the gas decomposition. The structure of the microwave reactor includes an insulating cover protruding into the plasma chamber and forming an internal cavity that is isolated from gases in the plasma chamber. A microwave antenna extends into the internal cavity of the plasma chamber to couple the microwave energy into plasma chamber for causing a plasma to form in the gases. A microwave generator generates microwave power. A microwave connector connects the microwave power from the microwave generator to the plasma chamber. The microwave connector includes a microwave transport for transporting the microwave energy, a first microwave coupler for coupling the microwave energy from the microwave generator to the microwave transport with a matched impedance, and a second microwave coupler for coupling the microwave energy from the microwave transport to the plasma chamber with a matched impedance The second microwave coupler includes the microwave antenna extending into the internal cavity of the plasma chamber.
The foregoing and other objects, features and advantages of the invention will be apparent from the following detailed description in conjunction with the drawings.


A lead screw actuator for displacing holder with a collimator lens in an optical scanning device has a home-position for accurately determining the position of the collimator lens. An anti-seize construction is provided to avoid the holder to get stuck against the home-position due to the friction between both surfaces.

The manufacturing process causes optical data carriers to have a substrate thickness that locally or globally deviates from the standard thicknesses as prescribed for example in standards for DVD or Blu-ray Disc (BD) optical data carriers. As the objective lens of the optical scanning device is designed for a specific substrate thickness, such deviations introduce spherical aberration in the scanning radiation beam of the optical scanning device when scanning such optical data carriers. The spherical aberration caused by a thickness error is particularly large in BD optical scanning devices because of the high numerical aperture (i.e. 0.85) of the objective lens. In multi-layer BD optical data carriers, e.g. dual-layer BD, a spacer layer separates the information layers on which data is to be recorded or scanned from. Such a spacer layer thickness may cause an additional error in the total thickness to be scanned through. Moreover, even when the manufacturing tolerances of the substrate thickness were very small, the fixed correction provided for in the objective lens would not suit the total thickness of each layer of a dual-layer BD disc. Hence accurate spherical aberration correction is required in order to read and/or write on such a BD disc, especially a multi-layer disc, with sufficient read and or write performance, for example, low jitter.
A known solution of correcting spherical aberration introduced in the scanning beam is a vergence change of the radiation beam towards to objective lens, e.g. by making a parallel radiation beam slightly converging or diverging depending on the sign of the thickness error. Such a change of vergence can be achieved by, for example, the moving-collimator-method: a controlled displacement of a collimator lens in radiation beam towards the objective lens introduces spherical aberration into the scanning beam in order to compensate the spherical aberration introduced by a substrate thickness error or by scanning an information layer at different depth in the optical data carrier than the objective lens was designed for. In order to correct the spherical aberration the actual position of the lens is preferably to be known.
JP2004-272945 discloses an actuator for displacing a collimator lens. The actuator comprises a motor driving a lead screw cooperating with a follower attached to a guided lens holder. The application discloses one or more specific configurations for avoiding errors in positioning when the displacement of the lens holder is reversed in direction.
At startup of for example a BD scanning system applying such a moving collimator, the collimator lens position can be unknown. For this, the collimator lens is displaced to a known location, e.g. a home-position or a stopping-position, at startup. A known solution to detect the home-position is by means of a light-interrupter.
Another method is to move the collimator lens to the home-position with an excessive number of steps of a lead-screw driven by a stepper motor. The collimator lens or holder with collimator lens will hit the home-position, stopping the displacement. A follower nut is attached to the collimator lens or lensholder. The follower nut is cooperating with the lead-screw that is to be driven by the motor. A reference-surface is provided to, for example, the lens holder or follower nut to come into contact with the home-position, thereby determining the position of the collimator lens.
A problem encountered with this method is that when the collimator lens is moved to the home-position the reference-surface can get stuck at this home-position. This is caused by a combination of the composition of the mechanical tolerances, friction variations and friction vectors between the lead-screw, follower nut, motor and home-position. The motor torque required for releasing the collimator lens from the home-position is larger than the torque required for homing. Depending on the available power the motor can apply the reference-surface may remain stuck against the home-position. This may especially occur, when in view of requirement such as, for example, low power consumption and miniaturization the motor has to be small and low power.
In order to avoid the reference-surface to get stuck to the home-position a large pitch of the thread of the lead-screw can be applied, however, this will result in inaccurate position-control of the collimator lens and thus inaccurate control of the spherical aberration correction.
It is an object of the invention to provide an improved actuator for displacement of a holder in which it is avoided that the reference-surface gets stuck against the stopping-surface of the home-position.

Actuator for displacement of a holder against a homing-position


Provided herein is a heretofore unknown isolated nucleic acid molecule which encodes human methylenetetrahydrofolate reducatase, along with an amino acid sequence of methylenetetrahydrofolate reductase, and a cDNA probe for human methylenetetrahydrofolate reductase. Also provided are a molecule description of mutations in humans resulting in a phenotype having reduced levels of methylenetetrahydrofolate reductase, and methods of diagnosing methylenetetrahydrofolate reductase deficiency in a human.

(a) Field of the Invention
The invention relates to a cDNA probe for human methylenetetrahydrofolate reductase (MTHFR), and its uses.
(b) Description of Prior Art
Folic acid derivatives are coenzymes for several critical single-carbon transfer reactions, including reactions in the biosynthesis of purines, thymidylate and methionine. Methylenetetrahydrofolate reductase (MTHFR; EC 18.104.22.168) catalyses the NADPH-linked reduction of 5,10-methylenetetrahydrofolate to 5-methyltetrahydrofolate, a co-substrate for methylation of homocysteine to methionine. The porcine liver enzyme, a flavoprotein, has been purified to homogeneity; it is a homodimer of 77-kDa subunits. Partial proteolysis of the porcine peptide has revealed two spatially distinct domains: an N-terminal domain of 40 kDa and a C-terminal domain of 37 kDa. The latter domain contains the binding site for the allosteric regulator S-adenosylmethionine.
Hereditary deficiency of MTHFR, an autosomal recessive disorder, is the most common inborn error of folic acid metabolism. A block in the production of methyltetrahydrofolate leads to elevated homocysteine with low to normal levels of methionine. Patients with severe deficiencies of MTHFR (0-20% activity in fibroblasts) can have variable phenotypes. Developmental delay, mental retardation, motor and gait abnormalities, peripheral neuropathy, seizures and psychiatric disturbances have been reported in this group, although at least one patient with severe MTHFR deficiency was asymptomatic. Pathologic changes in the severe form include the vascular changes that have been found in other conditions with elevated homocysteine, as well as reduced neurotransmitter and methionine levels in the CNS. A milder deficiency of MTHFR (35-50% activity) has been described in patients with coronary artery disease (see below). Genetic heterogeneity is likely, considering the diverse clinical features, the variable levels of enzyme activity, and the differential heat inactivation profiles of the reductase in patients' cells.
Coronary artery disease (CAD) accounts for 25% of deaths of Canadians. Cardiovascular risk factors (male sex, family history, smoking, hypertension, dyslipoproteinemia and diabetes) account for approximately 60 to 70% of the ability to discriminate CAD patients from healthy subjects. Elevated plasma homocysteine has also been shown to be an independent risk factor for cardiovascular disease.
Homocysteine is a sulfhydryl-containing amino acid that is formed by the demethylation of methionine. It is normally metabolized to cysteine (transsulfuration) or re-methylated to methionine. Inborn errors of metabolism (as in severe MTHFR deficiency) causing extreme elevations of homocysteine in plasma, with homocystinuria, are associated with premature vascular disease and widespread arterial and venous thrombotic phenomena. Milder elevations of plasma homocysteine (as in mild MTHFR deficiency) have been associated with the development of peripheral vascular disease, cerebrovascular disease and premature CAD.
Homocysteine remethylation to methionine requires the folic acid intermediate, 5-methyltetrahydrofolate, which is produced from 5,10-methylenetetrahydrofolate folate through the action of 5,10-methylenetetrahydrofolate reductase (MTHFR). Deficiency of MTHFR results in an inability to metabolize homocysteine to methionine; elevated plasma homocysteine and decreased methionine are the metabolic consequences of the block. Severe deficiencies of MTHFR (less than 20% of activity of controls) as described above, are associated with early-onset neurologic symptoms (mental retardation, peripheral neuropathy, seizures, etc.) and with atherosclerotic changes and thromboembolism. Milder deficiencies of MTHFR (35-50% of activity of controls), with a thermolabile form of the enzyme, are seen in patients with cardiovascular disease without obvious neurologic abnormalities.
In a survey of 212 patients with proven coronary artery disease, the thermolabile form of MTHFR was found in 17% of the CAD group and 5% of controls. In a subsequent report on 339 subjects who underwent coronary angiography, a correlation was found between thermolabile MTHFR and the degree of coronary artery stenosis. Again, traditional risk factors (age, sex, smoking, hypertension, etc.) were not significantly associated with thermolabile MTHFR. All the studies on MTHFR were performed by enzymatic assays of MTHFR in lymphocytes, with measurements of activity before and after heat treatment to determine thermolability of the enzyme.
Since 5-methyltetrahydrofolate, the product of the MTHFR reaction, is the primary form of circulatory folate, a deficiency in MTHFR might lead to other types of disorders. For example, periconceptual folate administration to women reduces the occurrence and recurrence of neural tube defects in their offspring. Neural tube defects are a group of developmental malformations (meningomyelocele, anencephaly, and encephalocele) that arise due to failure of closure of the neural tube. Elevated levels of plasma homocysteine have been reported in mothers of children with neural tube defects. The elevated plasma homocysteine could be due to a deficiency of MTHFR, as described above for cardiovascular disease.
Neuroblastomas are tumors derived from neural crest cells. Many of these tumors have been reported to have deletions of human chromosome region 1p36, the region of the genome to which MTHFR has been mapped. It is possible that MTHFR deletions/mutations are responsible for or contribute to the formation of this type of tumor. MTHFR abnormalities may also contribution to the formation of other types of tumors, such as colorectal tumors, since high dietary folate has been shown to be inversely associated with risk of colorectal carcinomas.
MTHFR activity is required for homocysteine methylation to methionine. Methionine is necessary for the formation of S-adenosylmethionine, the primary methyl donor for methylation of DNA, proteins, lipids, neurotransmitters, etc. Abnormalities in MTHFR might lead to lower levels of methionine and S-adenosylme-thionine, as well as to elevated homocysteine. Disruption of methylation processes could result in a wide variety of conditions, such as neoplasias, developmental anomalies, neurologic disorders, etc.
Although the MTHFR gene in Escherichia coli (metF) has been isolated and sequenced, molecular studies of the enzyme in higher organisms have been limited without the availability of an eukaryotic cDNA.
It would be highly desirable to be provided with a cDNA probe for human methylenetetrahydrofolate reductase (MTHFR). This probe would be used for identification of sequence abnormalities in individuals with severe or mild MTHFR deficiency, including cardiovascular patients and patients with neurologic symptoms or tumors. The probe would also be used in gene therapy, isolation of the gene, and expression studies to produce the MTHFR protein. The probe would also provide the amino acid sequence of the human MTHFR protein, which would be useful for therapy of MTHFR deficiency by biochemical or pharmacological approaches.
It would be highly desirable to be provided with a molecular description of mutations in methylenetetrahydrofolate reductase deficiency.
Patients with sequence abnormalities in MTHFR might have different responses to drugs, possibly but not limited to drugs that affect folate metabolism. Therefore, it would be useful to know if these mutations are present before determining the appropriate therapy. The drugs/diseases for which this might be relevant include cancer chemotherapeutic agents, antibiotics, antiepileptic medication, antiarthritic medication, etc.

Methods for detecting human methylene tetrahydrofolate reductase allelic variants


A method of manufacturing a semiconductor device, in which a first pattern of conductors (20), an isolating layer (21) and a second pattern of conductors (22) are successively provided on a surface (2) of a semiconductor body (1) adjoined by a number of isolation regions (4, 10) and a number of semiconductor regions (3). Mutual contacts are established between the two patterns (20, 22) and these contacts are located both above a semiconductor region (3) and above an adjoining isolation region (4, 10) by forming conductive pillars (44) in the first pattern (20), exposing a tip (51) of the pillars (44) after an isolating layer (50) has been provided and providing the second pattern (22) over the tip (51) of the pillars (44). Thus, a large amount is saved on the surface (2).

Through the openings in the isolating layer, interconnections are formed between the two patterns of conductors. The first pattern, which is provided on the surface of the semiconductor body, is locally in contact with semiconductor regions. Through interconnections these semiconductor regions are connected to the second pattern of conductors. Since the interconnections are formed at areas located both above a semicondutor region and above an adjoining isolation region, much space is saved on the surface of the semiconductor body. In practice, openings in the isolating layer, through which the interconnections are established, have dimensions which are determined by the manufacturing process comprising lithographic and etching processing steps. For example, such an opening has a cross-section of 1.times.1 .mu.m. If the interconnections are formed at areas located only above semiconductor regions, these semiconductor regions must have dimensions which are larger than those of the openings in the isolating layer If the interconnections are formed at areas located both above a semiconductor region and above an adjoining isolation region, the openings are consequently present only in part above the semiconductor regions so that these semiconductor regions can be considerably smaller. In the first case, the semiconductor regions must have, for example, a surface area of about 2.times.2 .mu.m, while in the second case they can have a considerably smaller surface area.
From the article "A New Device Interconnect Scheme for Submicron VLSI" by D. C. Chen et al. Technical Digest of the International Electron Devices Meeting, 1984, p. 118-121, a method is known of the kind mentioned in the opening paragraph, in which the mutual contacts are present at areas which are located both above semiconductor region and above a field isolation region. These contacts between the first and second patterns of conductors are established by etching into the isolating layers windows terminating on the first pattern of conductors and by providing the second pattern of conductors over the windows thus formed.
In the known method, in which both the isolating layer and the field isolation regions consist of silicon oxide, the first pattern of conductors serves as an etching stopper when etching the window. As a result, the yield oxide is protected during etching at the areas at which the window is formed. If this should not be the case, after etching the window into the isolating layer of silicon oxide, the field oxide is also etched. If the etching process is not stopped in time, the field oxide can locally be etched away entirely. After the second pattern of conductors has been provided, a pn junction terminating on the field oxide would be shortcircuited. Especially in those cases in which the pn junction extends comparatively closely to the surface of the semiconductor body, it is difficult to stop the etching process in time. This is certainly the case in semiconductor devices in which semiconductor regions, field isolation regions, conductors and contact windows having dimensions in the micron and the submicron range must be realized.
In the known method described, the first pattern of conductors serves as an etching stopper when etching the windows into the isolating layer. At the area of each window, for this purpose a part of the first pattern should be present having a surface area larger than the surface area of the cross-section of the window. In order to prevent the undesired etching of the field isolation region described above, this surface area must be at least so large that, when the window is formed, the etching stopper is present under all circumstances when etching the window. The window is defined by a photolithographic mask which is imaged on a layer of photoresist provided on the surface of the semiconductor body. After development, an opening of, for example, 1.times.1 .mu.m is formed in the photoresist. Subsequently, the window is etched while using the remaining photoresist as a mask. Since the photolithographic mask is imaged with a given alignment tolerance (of about .+-.0.3 .mu.m), the window mostly does not exactly arrive at its place. It is only certain that it arrives at an area which is as large as the mask extended with an edge equal to the alignment tolerance. In the embodiment with a window of 1.times.1 .mu.m, this is consequently an area of 1.6.times.1.6 .mu.m. If the part of the first pattern of conductors serving as an etching stopper when forming the window is provided by a similar photolithographic method, in which similar tolerances play a part, this part must have a surface area as large as the area at which the window is formed plus a strip having a width equal to the alignment tolerance. In the embodiment, this is consequently a square of 2.2.times.2.2 .mu.m. This requires on the surface a space which is again larger by the same amount. In the embodiment, this is consequently 2.8.times.2.8 .mu.m. For a window of 1.times.1 .mu.m, an etching stopper of 2.2.times.2.2 .mu.m must therefore be present, for which purpose a space of 2.8.times.2.8 .mu.m must be reserved on the surface of the semiconductor body.

Method of manufacturing a semiconductor device having interconnections located both above a semiconductor region and above an isolation region adjoining it


A portable flood water barrier system is disclosed having one or more portable, attachable, flexible modules. Each module comprises an elongated tubular member sealed at either end by rigid, flanged end caps. Each module is provided with one or more openings to permit the introduction of water, sand or similar material into the tubular member interior cavity. Each module is also provided with one or more sealable openings to permit any water, sand or similar material to be removed from the tubular member interior cavity. The material provides weight the module to hold it in position against the force of the moving floodwaters. With the tubular member interior cavity partially filled with the material the portion of the tubular member in contact with the ground substantially conform in shape to the ground contours to minimize any water seepage under the tubular member. Each end cap has a plate with a center section providing shoulders about which a retaining ring can be used to fix the tubular member between the shoulders and the inside surface of the retaining ring. The perimeter section of the end plate forms the flange that is provided with a series of bolt openings to permit end caps from adjacent modules to be bolted together. The outer face of each flange member can be structured to receive a gasket or other sealing member to form a watertight seal between to adjacent attached end caps.

1. Field of the Invention
This invention relates in general to portable fluid barrier systems, and more particularly to portable dams that can be positioned to protect buildings and other objects against damage from floodwaters.
2. Prior Art
Flooding from rivers and other water bodies that have overflowed their normal banks has year after year wrecked havoc on surrounding buildings, cars and other objects, as well as has caused death to livestock and humans in addition to destruction of farm land. Many attempts have been made to develop suitable barriers that could be quickly erected around buildings or along riverbanks to act as dams to prevent damage from flood waters. Although such barriers have been designed and developed, those that have worked have proven too expensive or too cumbersome to assembly and disassemble or too bulky to store when not in use.


A data recovery circuit for use in a data processing system where plural subsystems are linked by a bit serial transmission line. The data transmitted over the bit serial transmission line is in the form of a phase encoded (PE) pulse signal. The data recovery circuit includes a time delay circuit for delaying the PE pulse signal by a three-quarter bit period. The three-quarter bit period delay signal permits the generation of a control clock signal. The control clock signal is used in sampling the PE pulse signal at three-quarter bit period points in order to generate a control signal that indicates the absence or presence of a transition at the midpoint of each bit period of the PE pulse signal. The control signal is used to generate a recovered clock signal by logically combining the control signal with the PE pulse signal and a one-half bit period delayed PE pulse signal. The control signal is also used to generate a recovered data signal by clocking the control signal into two cascaded flip-flops and logically combining the outputs of the two cascaded flip-flops.

The present invention relates to data processing systems and, more particularly, to the transmission of data over a bit serial line or link between two subsystems of a data processing system.
Modern data processing systems are often comprised of a plurality of subsystems where each subsystem processes or generates data. For example, such systems may include one or more processing subsystems, disc subsystems, magnetic tape subsystems, and the like.
Because data processing and generating functions are spread over several subsystems, it is necessary for the subsystems to frequently communicate with each other. Since processors generally operate at high speeds, it is necessary that the transmission lines or links between the subsystems be capable of transferring data at a high speed comparable to the speed with which data is processed.
A number of approaches have been proposed in the past for providing high speed transmission lines between subsystems. One approach has been to provide a "common trunk", that is, a bus or plurality of transmission lines which carry data bits in parallel and which is connected to each subsystem. Common trunks are used in a number of current commercially available data processing systems, including, for example, the 8400 and 8500 series of data processing systems sold by NCR Corporation, Dayton, Ohio. The drawback to the use of the common trunk is, of course, that a large number of electrical conductors are required to provide the common trunk and, accordingly, it is expensive to manufacture. While the concept of transmitting data serially over a single transmission line or link has been known in the past, this approach has not been widely used for connecting subsystems within a single data processing system because of the high cost of the circuitry needed to serially receive and serially transmit the data at sufficiently high speeds to match the speed of the processors within the system.
Recently, there have been improvements in the cost and operating capability of integrated circuitry. For example, integrated circuits implemented in emitter coupled logic (ECL) can operate on data at much faster speeds than integrated circuits implemented in earlier logic families, and have a cost which is now comparable to the integrated circuits in earlier logic families. As a result, it is now feasible to use logic circuitry in conjunction with a bit serial link that can transmit data at speeds sufficiently high for use within data processing systems. Since these bit serial links use only one conductor line to transmit data and are, as a consequence, less expensive than common trunks, there has arisen the need for circuitry to transmit and receive the serial data at high speeds.
To transmit serial binary data over a transmission line normally requires that the data be somehow encoded. While encoding the binary data into analog signals is desirable for data transmission over long distances, because of the inherent greater immunity of analog signals to noise and interference, digital pulse encoding techniques are sufficient between data processing subsystems located within close proximity to each other.
A number of digital or binary encoding techniques have been employed in the past. These techniques include non-return to zero (NRZ) encoding, return to zero (RZ) encoding, phase encoding, and multilevel binary encoding, NRZ encoding is not suitable in many applications because it is not self-clocking, and accordingly, a separate clocking signal must be generated with the encoded data. RZ encoding likewise has disadvantages. While RZ does include some self-clocking features, the clock is sometimes very difficult to recover and accordingly, it is subject to some failure.
Multilevel binary encoding, on the other hand, is very reliable. However, it uses three or more voltage levels to transmit binary data and, as a consequence, requires extensive circuitry for converting between the binary data levels and the three voltage levels.
For the above reasons, phase encoding is perhaps the most ideally suited means of serially encoding binary or digital data in a data processing system. Phase encoded pulse signals use signal level transitions to carry both binary data and synchronization (clocking) information, and at least one signal level transition occurs during each bit period or interval. The various types of phase encoded pulse signals include the biphase-level code (also known as the Manchester code), the biphase-mark code (also known as the diphase code), and the biphase-space code. For a more detailed description of each of these binary pulse codes, reference can be had to a number of United States patents and printed publications including, for example, Fairchild Camera and Instrument Corporation, The Interface Handbook--Line Drivers and Receivers, Chapter 4 (1975).
A number of techniques have been used in the past for recovering data that has been encoded in phase encoded pulse codes. The recovering of the clocking or synchronization signal in the encoded data is one of the most vexing problems in the use of these codes, and phase locked oscillators are normally employed to aid in the recovery of the clocking signal. The disadvantage of phase locked oscillators is that they generally include extensive circuitry and are relatively expensive in cost. Furthermore, commercially available phase locked oscillators frequently have to be tuned so that they can operate with the specific frequency used in the code.
Techniques that have been used in recovering data are disclosed in U.S. Pat. No. 3,603,945, issued to Friedrich R. Hertrich, and U.S. Pat. No. 3,597,751, issued to Robert F. Neidecker and Friedrich R. Hertrich. The data recovery circuitry shown in each of these patents uses a delay circuit for delaying the read back signal from a magnetic recording apparatus, and combining the delayed read back signal with an undelayed read back signal. By detecting the amplitude of the combined signals, data can be recovered from the read back signal. The circuitry in both patents, however, is concerned with recovering data from a read back signal generated by magnetic fluxes on a magnetic medium that has the nature of an analog signal, rather than recovering the data from a signal that has the nature of binary pulses and that is transmitted over a bit serial link between two data processing subsystems.

Data recovery system for use with a high speed serial link between two subsystems in a data processing system


In byte-wise stuffing of synchronous signals of the synchronous digital multiplex hierarchy, jitter which complicates timing recovery occurs with phase-jumps of 8 UI. A possibility is therefore sought of converting jitter into drift. This is achieved using a phase-locked loop (PLL) in which a phase-jump compensator (7) is inserted between the output (4) of a phase discriminator (3) and the input (5) of an oscillator (6). The phase-jump compensator converts an input correcting quantity (K.sub.e) into an output correcting quantity (K.sub.a). When no stuffing is being performed, the input correcting quantity (K.sub.e) leaves the phase-jump compensator (7) unchanged (a1, b1). If positive stuffing (+St) is being performed, the pulses, thereby lengthened, of the input correcting quantity (K.sub.e) are firstly shortened to the standard duration (x1) and subsequently lengthened in a stepwise fashion to the original duration (c1, d1). In the case of negative stuffing (-St), by contrast, the pulses, thereby shortened, of the input correcting quantity (K.sub.e) are firstly lengthened to the standard duration (x 1) and then once again shortened in a stepwise fashion (e 1, f1).

The invention relates to a process for timing recovery in which the phase of an input clock pulse is compared with that of an output clock pulse, and in which the frequency of the output clock pulse is readjusted as a function of the result of comparison with the aid of a correcting quantity, and to a device for carrying out this process.
Such a process is known from the book "Theorie und Anwendungen des Phase-locked Loops", Best, 4th revised edition, AT Verlag Aarau, Stuttgart, 1987, pages 93 to 95.
A timing recovery device having a phase-locked loop, in which there is derived from the frequency of a quartz oscillator a sequence of phase-shifted internal clock pulses of which in each case one serves, controlled by the output signals of a phase discriminator, as readout pulse after frequency division, is the subject of U.S. Pat. No. 5,017,801.
A changeover is presently taking place in the technology of the transmission and multiplexing of digital signals from a plesiochronous to a synchronous operation. Whereas the conventional plesiochronous signals have a bit structure, the new synchronous signals have a byte structure, that is to say are organized in multiples of eight bits. This emerges from the CCITT Recommendations G.707, G.708 and G.709.
In multiplex technology, a plurality of digital signals are combined by interleaving to form a time-division multiplex signal. In the synchronous digital multiplex hierarchy this takes place in accordance with the byte structure in groups of respectively eight bits. Since the phases of the digital signals to be interleaved are frequently not fixed relative to one another, but drift with respect to one another as a function of the prehistory, it is necessary during interleaving to connect upstream phase matching.
The phase matching is performed by stuffing. In this case, in prescribed discrete time positions (time slots) of the outgoing multiplex signal either eight time slots assigned to the signal to be multiplexed are filled with its data or not--as a function of the instantaneous phase or frequency of the signal to be multiplexed relative to the multiplex signal. During stuffing, the phase of the synchronous signal to be multiplexed jumps accordingly by eight UI (unit intervals), or by one byte (8 bits), relative to the multiplex signal.
After transmission, the multiplex signal is once again resolved into its individual components. One of the problems thereby arising is the recovery of the original clock pulses of the multiplexed signals, for high demands are placed on the uniformity of these recovered clock pulses.
Irregularities occurring in the temporal sequence of the clock pulse edges are referred to as jitter. Since the jitter generated in different transmission links add together in their series connection, the jitter occasioned by individual causes must be narrowly limited. This also applies to the jitter that is caused by stuffing-induced phase-jumps.
A peculiarity of the transmission of digital signals resides in that phase fluctuations proceeding very slowly, so-called drift, are effectively tolerated by the transmission devices. Its permissible limiting values are therefore substantially higher than those of jitter.


An inclinometer is proposed wherein the degree and the orientation of the inclination of an apparatus, such as a vehicle or crane, relative to an artificial horizon can be measured and monitored by means of light barriers. This inclinometer comprises an annular vessel having light-transmissive walls and a hollow ring cover which partially embraces the annular vessel. The inner walls and outer walls of the hollow ring cover are provided with light sources and light receivers which are arranged opposite one another in pairs so as to form light barriers which penetrate the annular vessel and can be interrupted by a liquid contained in such vessel.

The present invention relates to a new and improved inclinometer in which light barriers are used to measure and monitor an inclination relative to an artificial horizon which is determined by the mirror plane of a liquid contained in a vessel and wherein a deviation exceeding an adjustable quantity in the position of a reference plane of the inclinometer relative to the artificial horizon triggers an alarm.
An inclinometer of this kind serves, for example, to warn a vehicle driver of the danger of his or her vehicle overturning when travelling over hilly terrain. Inclinometers designed as overturning warning devices which comprise a U-shaped vessel partially filled with liquid are in fact known to the art. For example, the French application No. 74 06386 describes an overturning warning device of this type comprising two floats. Such overturning warning device responds relatively well in the event of a tilting movement in the plane which contains the U-shaped vessel, but is insufficiently accurate in the case of tilting movements in other planes.


This invention enables users to interactively modify a schedule display in sequence in building or after completing a scheduling system in adaptation to the service environment, utility, and purpose of the system.. The class layer structure modifier is used to modify the way to group data objects. Then the information stored in the attribute definition storage device and the graphic object definition storage device is modified to correct display attributes and their ways of display in order to enable schedules to be displayed in a format suitable to a user's view.

A schedule display is a graphic representation on a screen of a collection of schedule data. The schedule data has a process start time, a process end time, a process machine, and other attribute values and it is referred to as a "unit". The specific way to make graphic representations depends on environments, usage, and each user's interest involved. In order to obtain a new display according to such dependency, an existing display program is sequentially modified to create a new display program while viewing the result of each modification. Customization of a display means such modification.
Factors affecting the way in which to make graphic representations are largely divided into two types: those which are associated with each user's view, which are usually determined by each user's interest, and those which are related to detailed graphic object definitions of graphic primitives. In the prior art, there is no available function which enables to modify a schedule display according to the former factors, or in response to a change in a user's view. In order to modify a display on account of the latter factors, on the other hand, some graphic routines of the GKS (Graphical Kernel System (GKS) International Standard (ISO 7942)) and the like are used for programming. This method has been problematic in that it is necessary to locate a part to be modified by checking through a source program inasmuch as it is impossible to find out in advance a suitable program corresponding to a particular graphic representation to be modified. It is none the less impracticable for a user to take the trouble to do so. This method has been problematic also in that a modification in a source program would entail such operations as compilation, which makes it impossible to make any such modification in interactive mode.
The prior patent publications, including JPUPA (Japanese Published Unexamined Patent Application) 61-23003 and PUPA 63-263566 containing references to the prior art pertaining to the preparation and display of schedules with the aid of computers or the like, contain no reference to the modification of a display of schedules according to a view.

Method and apparatus for customizing a schedule display

International Business Machines Corporation


A lawn mower having a driver's seat mounted on a vehicle body, an engine mounted rearwardly of the driver's seat, a radiator and a radiator fan disposed between the driver's seat and engine, an engine hood for covering the engine and radiator, and a muffler disposed in a space defined by an upper rear surface of the engine and the engine hood. The hood includes a rear wall defining an exhaust grille, and the muffler has an exhaust outlet opening in a direction along cooling air flows from the radiator fan to the exhaust grille. The cooling air flowing rearwardly by action of the radiator fan passes through the radiator and flows out rearwardly of the vehicle body, carrying heat from upper positions of the engine and heat radiating from the muffler. The muffler releases exhaust gas to be entrained by the cooling air flows.

1. Field of the Invention
The present invention relates to a muffler structure for an engine disposed on a rear portion of a vehicle, particularly a lawn mower.
2. Description of the Related Art
A lawn mower, as disclosed in U.S. Pat. No. 5,029,668, for example, has a muffler disposed in front of and below an engine to direct exhaust gas obliquely downwardly in order to avoid withering or burning of lawn by exhaust heat from the muffler. This known muffler system further includes a cooling fan having a vertical rotary shaft and disposed above the engine to cause cooling air to flow downwardly. A cooling air guide curved along a lower surface of the muffler is required for deflecting the cooling air flows.
In a muffler system as disclosed in the Japanese patent application laid open under No. 1990-293330, a muffler is disposed adjacent the center of a front wall of an engine, and an exhaust pipe extends downwardly from the muffler and bent to a lateral position to open in a transverse direction of a vehicle body.
In these conventional muffler systems, the muffler has an exhaust outlet not directly pointing to the ground to avoid adverse influences on lawn of the exhaust heat from the muffler. However, since the exhaust outlet is located forwardly of a driver's seat with respect to a moving direction of the vehicle, the exhaust gas from the exhaust outlet is not positively prevented from reaching the driver.
Further, since the opening direction of the exhaust outlet is a primary consideration, the muffler is not sufficiently cooled by air flows generated by the cooling fan, or an additional guide duct is necessary for guiding the air flows to achieve sufficient cooling.

Muffler system for an engine disposed rearwardly of a vehicle


A network device of a network environment may support burst switched technology. The network device may comprise a burst generator, a scheduler, and a content addressable memory to allocate the bursts to earliest available time slots. The burst generator may generate bursts, which may comprise packets having a common destination address. The scheduler may generate one or more content addressable memory entries comprising bits, which represent the time slots, generate key based on the size of the burst, and allocating the bursts to the earliest available time slots. The available time slots may be determined by comparing the key with the content addressable memory entries.

This application claims priority to Indian Patent Application No. 2142/DEL/2006 filed on Sep. 28, 2006.
A computer network refers to a group of interconnected network devices, which can share information and resources. The network device may comprise an end device such as a client and a server and an intermediate device such as a router or a switch. A group of intermediate devices may, together, form a core network and an intermediate device may support one or more end devices. For example, an ingress router, of the core network, may receive data units from one or more end devices and may send the data units to an appropriate egress router.
The core network may comprise high bandwidth networks such as optical burst switched networks. The ingress router of the core network may generate bursts with each burst comprising data units having a common destination and collected in pre-determined intervals. The ingress router may allocate time slots to each burst and the data units of the bursts may be sent onward during the allocated time slots. A software based approach to allocate time slots to the bursts may consume more time.

Allocating burst data units to available time-slots


An image forming apparatus includes a reading unit for reading an original image, and a recording unit for recording an image. A control unit is also provided which controls the relative timing between the operations of the reading unit and the recording unit. The operation of the control unit enables the apparatus to perform a reading operation in a first mode, in which the reading unit reads an original image without the recording unit performing a recording operation, in parallel with a recording operation in a second mode, in which a different original image, read by the reading unit, is recorded by the recording unit, such that vibrations caused by either the reading operation in the first mode or the recording operation in the second mode do not affect the other operation. As a result of the structure of the apparatus, an advantageous feature can be attained in which the timing of a writing operation is controlled in accordance with the movement of the reading scanner.

The present invention relates to an image forming apparatus having a facsimile function and a function of printing out data from a computer or filing the data in a recordable medium.
In recent years, a copying machine having a facsimile function, a printer function of printing out an output from a computer, or a function of storing the data upon connection of a magnetic disk or the like thereto has been developed as a multifunctional copying machine. In a copying machine of this type, an original reading unit (to be referred to as a scanner unit hereinafter) and a printer unit are independently and asynchronously operated to independently effect the respective functions.
In the conventional multifunctional copying machine described above, in a print-out operation of data from a host computer during, e.g., facsimile transmission, since the scanner unit and the printer unit are independently and asynchronously operated, a vibration caused by reverse movement of the scanner unit to the home position upon reading of an original and a vibration caused by stop movement of the scanner unit adversely affect the printer unit. That is, part of a printed image is blurred, vibrated, or partially omitted by these vibrations.
The above problem is not limited to a combination of the printer and facsimile functions for outputting data from a computer. This problem is also posed by, e.g., a combination of a function of recording an original in a magnetic disk or the like and the facsimile function, and a combination of a function of storing an original in a recording medium and the printer function.

Image forming apparatus where vibrations of the scanner do not affect the write operation


Vertical screening device (1) having at least one cylinder screen (2) and connectible with its lower end portion (8) to a similar screening device or a drive unit and, with its upper end portion (7), to a similar screening device or a distributor device. The screening device is adapted, together with the other devices connected to it, to be imparted a movement of rotation. The invention is charaterized in that the screening device (1) comprises a bearing device (3) for supporting a feed screw (4) cooperating with the cylinder screen (2). The bearing device (3) is disposed within the cylinder screen (2) and fixedly connected thereto. The feed screw (4) is connected through a link (5) extending outside the periphery of the cylinder screen (2), to a fixed point (6) provided outside the screening device (1) for holding the feed screw (4) stationary.

The present invention relates to vertical screening devices, and more particularly to a vertical screening device having at least one cylinder screen and adapted to be connected with its lower end portion to a similar screening device or a drive unit and, with its upper end portion, to a similar screening device or a distributor device, said screening device further being adapted, together with the other devices connected thereto, to be imparted a movement of rotation. The screening device may thus be of the type disclosed in Swedish Patent No. 434,349, although it must not necessarily be imparted an oscillating angular velocity. The screening device is so designed that it can be removed laterally once the connections with the other devices have been undone.


A three-dimensional (3D) rendering method and apparatus to render a 3D scene is disclosed. The 3D rendering apparatus determines color values of vertices shaded by a direct virtual light source, establishes one or more locations of one or more indirect virtual light sources in polygonal areas formed by the vertices based on the determined color values of the vertices, and renders a 3D scene based on the one or more indirect virtual light sources disposed at the determined one or more locations.

1. Field
The following description relates to three-dimensional (3D) computer graphics technology.
2. Description of Related Art
Three-dimensional (3D) rendering is used in various application such as, for example, 3D games, virtual reality, animations, videos, and movies. 3D rendering may be performed in various fashion, such as, for example, ray tracing that renders a 3D model by tracing a path through which light radiated from a light source is reflected from a surface of an object, radiosity rendering that applies not only a direct illumination effect but also an indirect illumination effect of light reflected from direct light by an object and of diffused reflection, and rasterization rendering that renders a 3D model by converting vector data to a pixel pattern image.


Pyrimidinyloxy(thio)quinoline derivatives represented by the formula (I) which exhibit an excellent controlling effect for plant diseases and are also safe for crop plants, preparation processes of the derivatives, and agri-horticultural fungicides comprising the derivatives as an active ingredient, are disclosed. ##STR1## In the formula (I), X is an oxygen atom or sulfur atom, Y is a hydrogen atom or halogen atom, Z is a hydrogen atom or methyl, R.sup.1 and R.sup.2 are methoxy or methyl, and n is an integer of 1 or 2.

1. Field of the Invention
The present invention relates to a novel pyrimidinyloxy(thio) quinoline derivative, preparation process of the derivative, and an agri-horticultural fungicide comprising the derivative as an active ingredient.
2. Related Art of the Invention
European Patent 326330 has disclosed that quinolines having aryloxy or arylthio at the position-4 have fungicidal activity.
However, the compounds described in the patent have primarily substituted phenyl as aryl groups. Heterocyclic groups disclosed are merely each one or two examples of pridyl, pyridazinyl, pyrazolyl and tetrazolyl, respectively. It is described that these heterocyclic groups exhibit very low or no controlling effect for diseases. Consequently, the subject matter of the above patent is that quinolines having substituted phenoxy at the position-4 of quinoline ring have an excellent controlling effect for diseases. The present inventors have conventionally paid attention to the good affinity of pyrimidines for organism and have investigated development of physiologically active substances. Accordingly, they have focused attention to the fact that quinolines having pyrimidinyloxy or pyrimidinylthio at the position-4 are novel compounds and have not yet been investigated at all, and have started investigation. For the purpose of comparison, compounds which are described to be excellent in the above patent have been tested. As a result, compounds having high controlling effect have caused chemical injury for crop plants, and those having low chemical injury have led to low controlling effect and been unsuitable for practical use.

Pyrimidinyloxy(thio)quinoline derivative, and agri-horticultural fungicide comprising the derivative as active ingredient


A bead locking apparatus includes bead support segments disposed in an annular arrangement at each of the axially opposite ends of a building drum mounted on a rotary shaft, the support segments being movable outward or inward radially of the drum, an elastic ring fitted in an annular recess formed in the outer periphery of the annular arrangement of segments, a segment drive device for moving the bead support segments radially outward, and a device for radially expanding the elastic ring independently of the segments. The bead is first primarily locked by the elastic ring and then secondarily locked by the support segments.

1. Field of the Invention
The present invention relates to a method of and apparatus for positioning beads around a tire component material wound around the building drum of a green tire building machine and locking the beads in position.
2. Description of Related Art
FIG. 6 shows a conventional machine for building green tires. The tire building machine comprises a headstock 55, a rotary shaft 56 supported at one end by the headstock 55 and a building drum 57 mounted on the rotary shaft 56. The periphery of the axial midportion of the drum 57 is provided with a building bladder 58 which is freely inflatable and contractable. The periphery of each of opposite ends of the drum 57 has a side bladder 59 which is also freely inflatable and contractable.
FIG. 7 is an enlarged view in section of the portion VII shown in FIG. 6, i.e., a conventional bead locking apparatus. The bead locking apparatus is disposed inside the side bladder 59 and positioned at each of opposite end portions of the drum 57. The apparatus has bean support segments 60 in an annular arrangement. These segments 60 are movable radially of the drum by being guided by slide keys 61 which are arranged radially. An annular recess 62 is formed in the outer periphery of the annular arrangement of bead support segments 60. An annular elastic member 63 of rubber or the like is fitted in the recess 62. The outer periphery of the elastic member 63 is smaller in diameter than large-diameter portions 60a of the annular assembly of segments 60 which portions define the recess 62 therebetween. The rotary shaft 56 is provided with a drive member 64 which is movable axially of the shaft and is connected to each segment 60 by a link 65. The drive member 64, when moved axially, moves the segments 60 radially.
Green tires are built by the following process using the abovementioned building machine.
A plurality of tire component materials 50, for example, a rubber layer 51 as the innermost layer, a steel cord reinforcement layer 52 over the layer 51, and a carcass 53 over the layer 52 and the layer 51 are each wound around the building drum 57 with the bead support segments 60 and the side bladders 59 contracted and a portion of each side bladder 59 one over another. Each of beads 54 is then brought in over convolution of the tire component material 50 to position around the segments 60. Next, the drive member 64 moves axially thereby expanding the annular arrangement of segments 60 to radially push the material 50 outward with the large-diameter portions 60a of the segment assembly, with the bead 54 positioned between the large-diameter portions 60a, 60a and pressed by the elastic member 63. The bead 54 thus positioned between the portions 60a is thereby prevented from moving in the axial direction and locked. The side bladder 59 is then inflated. The outer end portion of the material 50 is turned up around the bead 54 by forcing the inflated side bladder 59 inward axially of the building drum 57. Subsequently, the building bladder 58 on the drum 57 is inflated, whereby the material 50 positioned between the pair of beads 54 is shaped to a toroidal form.
The steps formed by the large-diameter portions 60a of the bead support segments 60 and the elastic member 63 of smaller diameter prevent the bead 54 from deflecting in the axial direction.
The steel cord reinforcement layer 52 of the tire component material 50 has a small width only sufficient to surround the bead 54 and is positioned only at each end of the carcass ply 53 as seen in FIG. 5. The steel cords 52a are in a bias arrangement as shown in FIG. 8.
Further as shown in FIG. 10, the carcass ply 53 of the tire component material 50 includes steel cords 53a which are arranged in parallel to the radial direction.
The bead locking method employed in the conventional building process described has the following drawbacks.
When the annular arrangement of bead segments 60 is radially expanded, the large-diameter portions 60a of the segments 60 first cause the side bladder 59 to press the tire component material 50. Accordingly, the material 50 radially expands to increase its circumferential length. This results in a delay in causing the elastic member 63 to contact the material 50 through the side bladder 59. The steel cord reinforcement layer 52 is therefore so deformed that the bias angle .theta. of the steel cords 52a ; becomes small as shown in FIG. 9. Further the steel cords 53a of the carcass ply 53 are bent by contact with the reinforcement layer 52 as shown in FIG. 11. Since such deformation is uneven, there arises the problem that the cord path (distance between the beads at opposite ends) becomes uneven over the entire circumference to impair tire uniformity. Further if a tire is made with steel cords 53a of the carcass ply 53 in a bent state, another problem is encountered, that is, when the tire is inflated with air, the steel cords 53a stretch and rotate as bent to impair the durability of the tire.
Further when the arrangement of segments 60 is expanded, a clearance occurs circumferentially of the arrangement between the adjacent segments, with the result that with respect to the circumferential direction, the material 50 is locally pressed by the large-diameter portions 60a of the segment arrangement and left unpressed also locally. Thus, the material 50 is deformed unevenly with respect to the circumferential direction of the tire.
Stated more specifically, the material 50 is pressed radially from inside by the pair of large-diameter portions 60a on opposite sides of the bead 54 and is also pressed radially from outside by the bead 54. Accordingly, the material 50 is supported at three points, and this mode of support is low in stability. When the segment arrangement is further expanded, the material 50 is held between the bead 54 and the elastic member 63. When thus held, the material 50 is supported with good stability with respect to the axial direction.
Until the elastic member 63 starts to press the tire forming material 50 after the large-diameter portions 60a start to press the tire component material 50, the material 50 is supported by these portions 60a and the bead 54 with very low stability. Accordingly, it is likely that slippage will occur between the material 50 and the large-diameter portions 60a or between the bead 54 and the material 50, although such slippage does not always occur. As a result, the material 50 as positioned between the bead 54 and the large-diameter portions 60a is stretched by being pulled or will remain unstretched to undergo uneven deformation. It is also likely that the bead 54 will move in the axial direction.
If the material 50 deforms unevenly with respect to the axial or circumferential direction, or if the bead 54 becomes shifted, the cord path (the bead-to-bead distance) will vary circumferentially of the tire. This causes the problem that variations in cord path adversely affect tire uniformity.

Bead locking apparatus for green tire building machine


A pulse-excited mercury-free lamp system, and method of sustaining the emission of light emission from such a lamp, is provided. The system includes a light-transmissive envelope having an inner surface and a phosphor layer coated thereon. A discharge-sustaining gaseous mixture of a noble gas, at a low pressure, and a metal halide, is retained inside the light-transmissive envelope. An electrical system provides a plurality of pulses to the discharge-sustaining gaseous mixture, resulting in a discharge, which causes the lamp system to emit light. The emission of light is maintained by turning the discharge on during a pulse width of each pulse in the plurality of pulses and by turning the discharge off during a remainder of each period in the plurality of pulses. Particularly in systems where the metal halide is indium-based, this maintains an efficient emission of light without the use of mercury.

Typical gas discharge lamps include a small amount of mercury, which is used to excite the discharge that results in the lamp producing light. While mercury performs this function very well, the potential damage to the natural environment and to people that may be caused by mercury is now very well known. Thus, reducing and/or removing mercury from lighting has long been a desired goal.
One alternative to using mercury to excite a discharge is to use a low pressure indium chloride discharge instead of mercury. Under certain conditions, such as the discharge current, the temperature of the indium chloride concentrate, the temperature of the bulb wall, and the type and pressure of the fill gas within the lamp, an indium chloride discharge can effectively replace mercury within a low pressure discharge lamp, with minimal or no loss in lamp efficacy.