A positioning stage assembly having a coarse stage which includes a planar motor driveable in at least two degrees of freedom, and a fine stage positioned on the coarse stage which is driveable in at least three degrees of freedom with respect to the coarse stage. More preferably, the fine stage is driveable in six degrees of freedom and includes variable reluctance actuators for positioning in three degrees of freedom.

The need for precise positioning of an object is required in many fields of application, including applications in semiconductor manufacturing such as microlithography. As microprocessors become faster and more powerful, an ever increasing number of transistors are required to be positioned on a semiconductor chip. This necessitates closer placement of the transistors and circuits interconnecting them, which in turn requires an ever increasing accuracy in the methods for laying down the circuits on the chip. Thus, there is a need for more precise positioning and maintaining of position, of a substrate during microlithography.
Various systems have been designed to attempt to improve fine positioning and movement control of a work piece. British Patent Specification 1,424,413, assigned to Handotai Kenkyo Shinkokai describes several stage that are supported by flexures and actuated using electromagnetic force actuators. U.S. Pat. No. 3,935,486, invented by Nagashima describes a stage that is controlled using electromagnetic force actuators. In this case, the stage is supported on flexural bearings in 6 degrees of freedom (DOF) and the actuators are used to adjust the position of the stage. Both of these designs utilize flexural bearings to constrain the motion of the stages in 6 DOF. The electromagnetic actuators only provide force; they are not used to control all directions of motion of the stage. Nor is there any disclosure of providing a linear motor driven coarse stage.
Ideally, the bearings for a stage should have infinite stiffness in the directions for which position of the stage is to remain fixed, and zero stiffness along the directions in which the stage is to be moved, to maximum precision and efficiency. Flexural bearings fall far short for the ideal and generally have a stiffness ratio (stiffness in directions to be fixed to stiffness in directions to be moved) of only about 100:1 and possibly up to about 1000:1 but the price of the latter is likely prohibitive in practice. Moreover, a much greater stiffness ratio is desirable.
U.S. Pat. No. 4,952,858 invented by Galburt describes a wafer fine stage that is supported and positioned in 6 DOF by electromagnetic voice coil motors. The motion of the wafer fine stage is entirely constrained using voice coil motors, and this design does not utilize any flexural bearings. Voice coil motors, however, require relatively large amounts of power to generate a given amount of force. The high power requirements of voice coil motors can generate sufficient heat to change the index of refraction of the environment sufficiently to induce error in an interferometer system. Additionally, heat generation can cause expansion of the stage leading to further errors in alignment and control. Further, U.S. Pat. No. 4,952,858 discloses the use of permanent magnets to counterbalance the weight of the fine stage. This counterbalance force is a nonlinear function of stage position, and is thus quite difficult to control accurately.
U.S. Pat. Nos. 5,157,296 and 5,294,854, invented by Trumper describe a wafer fine stage bearing system. This system includes electromagnetic actuators, which act as bearings in 6 DOF. These patents describe control means for the bearings and apparatus for counterbalancing the weight of the stage using either opposed permanent magnets or a heavy oil in which the stage floats. U.S. Pat. Nos. 5,157,296 and 5,294,854 also do not utilize flexural bearings. The electromagnetic actuators in the Trumper patents are arranged in pairs, on opposite sides of the stage, in order to provide stable control. Thus, all forces applied by the electromagnetic pairs are transmitted through the stage, which can result in deformation of the stage.
The counterbalance forces in the Trumper patents may be provided by permanent magnets or by floating the stage in oil. As noted above with regard to the Galburt patent, utilization of permanent magnets results in a nonlinear force curve and corresponding control problems. With regard to floating the stage in oil, oil presents significant problems for a clean room environment typically used for semiconductor processing.
U.S. Pat. No. 5,528,118, invented by Lee, describes a guideless stage for aligning a wafer in a microlithography system, and a reaction frame which isolates both external vibrations as well as vibrations caused by reaction forces from an object stage.
U.S. Pat. No. 5,623,853, invented by Novak, et al., describes a wafer coarse and fine stage for a lithography machine. The coarse stage is a stacked arrangement of linear motor-driven air bearing slides. The fine stage is driven in 3 DOF using voice coil motors. The remaining DOF of the fine stage are constrained using flexural bearings. The use of flexural bearings for the 3 planar DOF limits the servo bandwidth of the stage because the flexural bearings have a limited stiffness in the plane. In addition, the finite stiffness of the flexural bearings out of the plane, distorts the out of plane motion of the stage.
In addition to the above described attempts at providing a superior fine stage design, various attempts have also been made to provide planar motors for use in driving positioners in the field. Disclosures in the field of planar motors include Hinds, U.S. Pat. No. 3 51,196; Hinds, U.S. Pat. No. 4,654,571; Trumper, U.S. Pat. No. 5,196,745; and Chitayat, U.S. Pat. No. 5,334,892. These patents describe planar motors that have significant limitations. For example, the planar motors of Hinds '196 has limited range of motion because each portion of the stationary magnet array can only generate force in a single direction. Thus, each coil array must always be located above the corresponding magnet array. This limits the range of movement for a given size actuator. In addition, the coils and magnets are iron-core and generate sizable attractive forces as well as force ripple. This does not allow for motion in six degrees of freedom because the levitation force cannot overcome the attractive force between the two pieces. Additionally, none of these attempts have combined, or suggested to combine a fine stage operating in conjunction with a planar motor coarse stage.
Hinds '571 suffers from a non-compact design. A large portion of the base of the moving portion of the stage is covered by the air bearing pads and other elements. Only a small portion of the stage is covered with coils. In addition, the coil design is not the most efficient for producing force, since at most only fifty per cent of the coil can generate force. In addition, the moving coil design has a large number of hoses and cables going to the stage, creating a large bias force. Finally, this design does not generate force for a six-degree-of-freedom movement.
Trumper discloses several stage designs with six degrees of freedom. The invention uses conventional coils. Each coil array must be located above a corresponding linear magnet array. This restricts the range of movement for a given sized stage.
Chitayat discloses several planar motor designs, which permit a wide range of motion, but only restricted to translation and rotation in a plane. Thus, the motor of Chitayat is incapable of moving with six degrees of freedom.
Kim and Trumper, in "High-Precision Magnetic Levitation Stage for Photolithography", American Society for Precision Engineering, 1997 Proceedings, Volume 16, pp. 470-473, discloses the design of a permanent magnet linear motor, for use in a magnetically-levitated wafer stepper stage in which four linear motors provide both suspension and drive forces.
Holmes et al., in "A Long Range Scanning Stage", American Society for Precision Engineering, 1997 Proceedings, Volume 16, pp. 474-477, discloses a long range scanning stage, having 25 mm×25 mm mobility in the X-Y plane and
Kim and Trumper, in "Precision Control of Planar Magnetic Levitator", American Society for Precision Engineering, 1998 Proceedings, Volume 18, pp. 606-609, discloses a stage that provides fine motion control in six degrees of freedom. The key element is a linear motor capable of providing suspension and translation forces without contact.
Asakawa, U.S. Pat. No. 4,555,650, discloses a two-dimensional driving device for use in a positioning device for a semiconductor manufacturing apparatus. A magnetic field group is formed by disposing magnetic fields on a plane in a two-dimensional array. At least two coils are distinctly oriented so as to provide a driving force in each of two orthogonal directions. Asakawa, U.S. Pat. No. 4,535,278 also provides a two dimensional driving arrangement for "precision" positioning through use of a planar array of magnetic fields that interact with appropriately oriented coils. Since the devices disclosed in these patents are not capable of positioning in greater than two degrees of freedom, there is a need to provide a finer control in a portioning device.
Sawyer, U.S. Reissued Pat. No. Re. 27,289 discloses a magnetic system for moving a marking tool over a surface for plotting curves. Sawyer, Reissue Pat. No. Re. 27,436 discloses a two-axis magnetic system for driving chart plotters. The Sawyer Reissue patents are not only not directed to the semiconductor-positioning field, but they also are limited to positioning along only two degrees of freedom. Additionally, they use variable reluctance to drive the devices and consequently have cogging forces and relatively low precision.
Trost et al., U.S. Pat. No. 4,506,205 discloses an electromagnetic alignment apparatus for use in aligning wafers in a microlithography system. The apparatus includes three or more spaced magnets that are fixed and interact with three or more spaced coil assemblies that move to effect positioning. As a result, the structure can be moved selectively in three degrees of freedom.
Siddall, U.S. Pat. No. 4,694,477, discloses an apparatus for micro positioning an X-ray lithography mask, in which three piezoelectric transducers are provided for moving a stage plate in the X-Y plane, and three flexure assemblies support the stage plate and move the stage plate along the Z-axis. As noted above, the use of flexural bearings limits the servo bandwidth of the stage because the flexural bearings have a limited stiffness in the plane. In addition, the finite stiffness of the flexural bearings out of the plane, distorts the out of plane motion of the stage.
Reeds, U.S. Pat. No. 4,891,526 discloses a positioning stage for high speed step and repeat alignment of a semiconductor wafer to a mask with six degrees of freedom. Linear bearings are provided on a first plate for movement in the X-direction, and this sub stage is also mounted on an intermediate stage that is mounted on another set of linear bearings for movement in the Y direction. The entire X-Y stage is then mounted on a rotation stage platform.
What is needed that is not provided in the prior art is an improved stage positioner in which higher fine stage mechanical bandwidth is obtained by improving the stiffness characteristics of the bearings/drivers supporting the fine stage. A related advantage to be obtained thereby is the elimination of cross coupling between X or Y axis acceleration forces and Z axis motion. In several embodiments, an advantage is obtained in the ability to control the fine stage through feed-forward actuation of the bearings supporting the fine stage. Another need is to reduce the complexity and improve the performance of a coarse stage on which the fine stage is mounted. A planar motor can provide motion and force in at least two directions, thereby eliminating the need for a set of stacked X-Y stages. This reduces the mechanical complexity and mass of the coarse stage, and increases the stiffness by removing joints between the stacked stages, all of which results in improved dynamic performance of the apparatus.

Wafer positioner with planar motor and mag-lev fine stage


A multi-part intraocular lens (IOL) with an interchangeable optic seated on a base and secured by a locking mechanism. The optic comprises an anterior surface with a diameter greater than a diameter of a ring of the base. The posterior side of the optic has a posterior surface, a transition region for contact with the base, and sidewalls and tabs radially outward of the transition region. The sidewalls and tabs overlap at least a portion of the ring to reduce or even prevent decentration and tilt of the optic. Each tab has a lateral extension for coupling to the base.

The human eye functions to provide vision by transmitting light through a clear outer portion called the cornea and focusing the image by way of a crystalline lens onto a retina. The quality of the focused image depends on many factors including the size and shape of the eye and the transparency of the cornea and the lens.
The crystalline lens is a transparent, biconvex structure in the eye that, along with the cornea, helps to refract light to be focused on the retina. The lens, by changing its shape, functions to change the focal distance of the eye so that it can focus on objects at various distances, thus allowing a sharp real image of the object of interest to be formed on the retina. This adjustment of the lens is known as accommodation and is similar to the focusing of a photographic camera via movement of its lenses.
Ageing or other ocular diseases cause the crystalline lens to become less transparent (e.g., cloudy), vision deteriorates because of the diminished light, which can be transmitted to the retina. This deficiency in the lens of the eye is medically known as a cataract. Currently available treatment for this condition is to surgically remove the crystalline lens from the capsular bag and placement of an artificial intraocular lens (IOL) in the capsular bag. A majority of cataractous lenses are removed by a surgical technique called phacoemulsification. During this procedure, an opening (capsulorhexis) is made in the anterior side of the capsular bag and a thin phacoemulsification-cutting tip is inserted into the diseased lens and vibrated ultrasonically. The vibrating cutting tip liquefies or emulsifies the lens so that the lens may be aspirated out of the capsular bag. The cataractous lens, once removed, is replaced by an IOL.

Multi-part intraocular lens with locking mechanism


A field effect transistor comprises, at least, a channel forming region formed in a semiconductor layer, and a gate electrode provided in face-to-face relation with the channel forming region via a gate insulating film, wherein the semiconductor layer is made of a mixture of a semiconductor material layer and conductive particles. The field effect transistor is capable of enhancing a carrier mobility.

This invention relates to a field effect transistor and a method for manufacturing the same.
Field effect transistors (FET) including thin film transistors (TFT) that have now been used in a variety of electronic appliances are constituted, for example, of a channel-forming region and source/drain regions formed on a silicon semiconductor substrate or silicone semiconductor layer, a gate insulating layer formed on the surface of the silicon semiconductor substrate or silicone semiconductor layer and made of SiO2, and a gate electrode provided in face-to-face relation with the channel-forming region through the gate insulating film. Alternatively, the transistor may be constituted of a gate electrode formed on a substrate, a gate insulating layer formed on the substrate including the gate electrode, and a channel-forming region and source/drain regions formed on the gate insulating layer. For the manufacture of the field effect transistors having such structures, a very expensive semiconductor apparatus has been in use, and thus the reduction of manufacturing costs has been strongly demanded.
In order to meet the demand, attention has been recently made to studies and developments of FET using organic semiconductor materials, with which FET can be manufactured based on methods such as a spin coating method, a printing method, a spraying method, without resorting to vacuum techniques.
FET is required to exhibit high-speed operations because of the requirement of being assembled in many electronic appliances including displays. For instance, FET necessary for this purpose is such that video signals are converted to data as occasion arises and switching operations of on/off can be performed at high speed.
Where organic semiconductor materials are used, the mobility that is a characteristic index of TFT, for example, is obtained as a typical value which is as low as 10−3 to 1 cm2/Vs (see, for example, C. D. Dimitrapopoulos, et at., Adv. Mater. (2002), 14. 99). This value is lower than several cm2/Vs of the mobility of amorphous silicon or about 100 cm2/Vs of the mobility of polysilicon, and thus does not arrives at such a mobility of 1 to 3 cm2/Vs as required for TFT for displays. Accordingly, FET using organic semiconductor materials has a great problem on how to improve mobility.
The mobility of FET using an organic semiconductor material is determined depending on the intramolecular charge transfer and the intermolecular charge transfer. The intramolecular charge transfer becomes possible when atomic orbitals are superposed between adjacent multiple bonds sandwiching a single bond so that electrons are non-localized to form a conjugated system. The intermolecular charge transfer is realized through conduction resulting from the superposition of molecular orbitals caused by intermolecular bond or van der Waals' force or the hopping conduction through an intermolecular trapping level.
In this case, when the intramolecular mobility is taken as μintra, the mobility of intermolecular bond taken as μinter, and the mobility based on the intermolecular hopping conduction taken as μhop, the following relationship is established.μintra>>μinter>μhop
With organic semiconductor materials, the mobility is limited, as a whole, with the slow intermolecular charge transfer, so that the mobility of charge is small.
In order to improve the mobility of FET using organic semiconductor materials, studies have been extensively made.
For instance, where a pentacene thin film which is a kind of organic semiconductor material is formed according to a vacuum deposition technique, the deposition rate during the deposition is suppressed to an extreme extent and the substrate temperature is set at room temperature thereby improving orientation of molecules and arriving at a mobility of 0.6 cm2/Vs (see C. D. Dimitrakopoulos et at., IBM J. Res & Dev. (2001), 45, 11). This method aims at improving the mobility by improving the crystallinity of material and suppressing the intramolecular hopping conduction. Although the mobility is improved, the intramolecular movement limits the mobility as a whole like other types of organic semiconductor materials. Eventually, such a great mobility as to be satisfied cannot be achieved.
For an organic semiconductor transistor positively using intramolecular charge transfer, a self-assembled monolayer field-effect transistor (SAMFET) of Luscent Technology Inc., has been proposed. In this device, a semiconductor layer made of a monolayer is formed between a source electrode and a drain electrode through self-assembling thereby realizing SAMFET having a gate length of 15 nm. In this SAMFET, the channel-forming region is constituted of the monolayer that is oriented along the direction of connecting the source electrode and the drain electrode, so that the charge transfer within the channel-forming region is limited only to the intramolecular movement. As a consequence, a mobility of 290 cm2/Vs that is higher than that of polysilicon has been achieved (see J. H. Schoen et al., Nature (2001), 413, 713; Appl. Phys. Lett (2002), 80, 847). However, such a channel structure has a gate length which is determined depending on the thickness of the monolayer film, so that the gate length becomes so short as several nanometers. This brings about the problem that the pressure resistant between the source and drain regions becomes low, not making it possible to achieve a high drive voltage. For the formation of electrodes on the monolayer film without breakage of the monolayer film, the substrate temperature should be cooled down to −172° C. to −30° C., and thus process costs become high. Thus, this process has little practical merits.
A channel material using a blend of organic and inorganic materials has been proposed in Japanese Patent Laid-open No. 2000-260999. More particularly, while, in the technique disclosed in Japanese Patent Laid-open No. 2000-260999, a layer structure is formed of an inorganic component and an organic component to utilize the high carrier mobility characteristic of the inorganic crystalline solid on one hand and the ability of the organic component assisting in self-assembling of the inorganic material on the other hand, deposition of the material on a substrate under low temperature processing conditions is enabled. Although a mobility of 1 to 100 cm2/Vs has been expected, the mobility actually achieved is as low as 0.25 cm2/Vs. This value is higher than that of an organic semiconductor material generally formed according to a spin coating technique, and is at the same level as that of an organic semiconductor material formed by vacuum deposition or the like. The mobility higher than that achieved by amorphous silicon has never been obtained.


A device and method to accelerate solid metal slugs to high speeds. In one embodiment, a large electric current is passed through an outer cylindrical metal tube enclosing in part a metal slug, a central electrode, and a conducting tail coupled at opposite ends to the. metal slug and the central electrode. Electromagnetic forces accelerate the metal slug to a point high enough to mechanically separate the conducting tail. On separation, a plasma is generated by the passage of electric current though a gas produced by vaporization of the conducting tail and nearby materials. An insulator enclosed within the tube prevents the plasma from shorting to the outer tube until the current flow has produced a sufficient magnetic field to contain the plasma. The metal slug is then accelerated to high speed by a combination of electromagnetic forces and mechanical pressure from the hot gas through which the electric current is passing.

1. Field of the Invention
The present invention relates generally to electromagnetic acceleration of metal projectiles.
2. Description of the Related Art
High velocity metal slugs have a variety of uses, but rather large and complicated facilities, e.g. staged gas guns, are required to produce speeds of over about 1 km/s. Chemical propellants ignite and produce a high pressure gas that pushes metal slugs out of gun barrels. The speed that can be achieved is limited by the speed of sound in the combustion products, which may reach a few thousand degrees Kelvin (K). Speeds nearing 1.2 km/s have been achieved in some prior art systems but are not normally reached. Prior art railguns routinely accelerated projectiles to speeds greater than 1.2 km/s; however, railgun barrel construction is complicated and expensive, and the barrel lifetime is limited. In prior art railgun systems, immense forces push the rails apart, and very strong containment is required; insulators are utilized to separate the conducting rails, and large power supplies are required.

Electromagnetic device and method to accelerate solid metal slugs to high speeds

The United States of America, as represented by the Secretary of the Navy


A method and computer system having a processor are provided for selectively compressing a data communication frame for data transfer between the computer system and at least one other system. A processor work load is periodically identified for the processor. A predetermined stored threshold value is identified and compared with the identified processor work load. Responsive to an identified processor work load greater than the identified predetermined threshold value, the data communication frame is transmitted without compressing the data communication frame. Otherwise the data communication frame is compressed and then transmitted responsive to an identified processor work load less than or equal to the identified predetermined threshold value. A state of a communication line is identified for the data transfer. Responsive to an identified idle state of the communication line, the data communication frame is transmitted without compressing the data communication frame.

1. Field of the Invention
The present invention relates generally to data communications using data compression, and more particularly to a method and a computer system for dynamic management of data compression.
2. Description of the Prior Art
Data compression has been increasingly used because it provides improved communications performance by reducing the amount of transmitted data and/or reduces the cost of data communications. Data compression is used on various known communications controllers.
Various compression algorithms have been employed for data compression. Examples of data compression algorithms are disclosed in U.S. Pat. Nos. 4,386,416, 4,663,490, 4,663,660 and 4,684,923.
U.S. Pat. No. 4,631,598 discloses an image processing system including a video converter board that transmits data to a spatial compressor board which compresses data electronically in the x-direction or the direction of the linear array. Data compression in the y-direction is accomplished by motor speed control movement of the document. A scanner controller provides data compression for the end user to match the data handling capabilities of the end user system. The image processing system uses automatic thresholding techniques with respect to grey scale and edge detection threshold parameters.
U.S. Pat. No. 4,598,411 discloses a data compression system for compressing data transmitted between a data source and an ultimate utilization device. Data is compressed "on-the-fly" in that the data is compressed as it is transmitted, instead of compressing and storing the compressed data in memory before it is transmitted.
Japanese patent No. 59189751 issued Oct. 27, 1984 to Nakayama et al., discloses a data transmission control system including a central processing unit (CPU) and a communication controller (CCU). Image data is sent to the CCU by the control of the CPU. The CCU transfers received data to an attachment corresponding to a line through which data should be transmitted. In the attachment, a start part of the image data is read to determine whether or not the data is compressed. If the data from the CPU is not compressed, the CCU compresses the data before it is transmitted. Otherwise, if the data from the CPU is compressed, the CCU will bypass the compression step and transmit the data in its existing compressed form.
One significant disadvantage of the above and many of the known data compression methods is that degraded performance can result. Data compression adds to the processing overhead and can result in inefficiency in the processor system. When the processor utilization is high, data compression further increases the processor utilization resulting in degraded performance. Another problem is that data compression may not result in any actual data transmission savings. The time spent either attempting to or providing the data compression can cause a delay in the actual transmission of the data and degraded performance. For example, when using a high speed communication line and the communications hardware is idle, the time spent compressing data causes an overall delay for the start of data transmission.
U.S. Pat. No. 4,905,171 issued Feb. 27, 1990 to Harvey G. Kiel et al. and assigned to the present assignee, discloses a workstation controller (WSC) performance monitor for locating performance bottlenecks. Performance measurements are taken and processor utilization and communications line utilization are calculated. Processor utilization is calculated using an idle loop for generating an idle loop count and using the following equation: ##EQU1## where the idle loop count equals the number of times an idle loop was executed, the elapsed time of the test equals a predetermined time period for retrieving measurements, and the idle loop time is a constant equal to the time required to execute the idle loop once.

System for selectively compressing data frames based upon a current processor work load identifying whether the processor is too busy to perform the compression

International Business Machines Corporation


A support structure for an intake system of an internal combustion engine. The support structure includes first and second mount portions provided on an engine-mounting flange portion of an intake manifold, the intake manifold being fitted to the engine by the engine-mounting flange portion, and a third mount portion is disposed on a throttle body-mounting flange portion of a surge tank, the throttle body being mounted on the surge tank through the throttle body-mounting flange portion. The support structure also includes an intake manifold stiffener having a substantially triangular shape which includes first, second, and third mounting sections at the corners thereof. These mounting sections are engaged with the first, second, and third mount portions, respectively. Accordingly, the surge tank is supported by the triangular configuration of the intake manifold stiffener. In addition, the first and second mounting sections have a greater length in the direction of each mounting axis thereof to define additional space for accommodating other engine components.

An internal combustion engine typically has a throttle body and a surge tank arranged in sequence from the upstream side of an intake system, or rather an intake manifold. The intake manifold and the surge tank communicate with one another through an intake manifold stiffener.
One such example of a support structure for an 35 intake system is disclosed in published Laid-Open Japanese Patent Application No. 5-65857. In the support structure disclosed therein, a throttle body-mounting flange portion is provided at a collection portion (i.e., a surge tank portion) of an intake manifold. The intake manifold is made of resin or steel pipe, and has a plurality of individual intake passage portions extending toward the collection portion from an engine body in a downwardly curved manner. The intake passage portions are mounted at downstream ends thereof to the engine body, but are connected at upstream ends thereof to the surge tank portion. In addition, a stay member, whose one end is mounted on the engine body, is engaged at the other end thereof with the above-mentioned throttle body-mounting flange portion. As a result, the intake manifold is supported at the surge tank portion by means of the stay member.
Another example of such a support structure is disclosed in published Japanese Utility Model Registration No. 2518964. The support structure for the intake manifold as disclosed therein includes a surge tank and a branch pipe arrangement. The branch pipe arrangement is integrally connected at the top thereof to the surge tank, while being joined at the bottom thereof to one sidewall of a cylinder head. A reinforcement portion is provided on an outer surface of the outermost branch pipe of the branch pipe arrangement. The reinforcement portion has a greater thickness at a location approximately midway from a proximal end of the branch pipe positioned toward the engine body. Further, an upper support stay extends between a proximal end of the reinforcement portion and an outer end portion of the surge tank. In addition, a lower support stay extends between a distal end of the reinforcement portion and a cylinder block skirt portion or mission case.
In conventional support structures for the intake system of the internal combustion engine and, particularly, in intake manifold stiffeners for supporting the surge tank on the upper sides of branch pipes of the intake manifold, the surge tank being attached on the upstream side of the intake manifold, a great number of intake manifold stiffeners are available that are made of either simply structured metal plates or steel pipes. However, the above-mentioned intake manifold stiffeners are typically unable to control vibrations of the surge tank or throttle body. The surge tank and the throttle body each have respective sensors fitted thereto, and such vibrations are an inconvenience since they can adversely affect the sensors, which is disadvantageous in practical use.
In addition, a large number of the above stiffeners are designed for mounting at two locations in total. More specifically, such an intake manifold stiffener is mounted both on the surge tank at one location and on an engine-mounting flange portion of the intake manifold at another location. The intake manifold is mounted on the engine through the engine-mounting flange portion. Such a mounting method is typically unable to control deformation; therefore there has been a continuous demand for an improved mounting method.
A further inconvenience is that the stiffener cannot be provided at a location which effectively increases the rigidly of the stiffener due to the positioning of an injector, a fuel delivery pipe, a harness, a throttle body, and accelerator cable, etc., on the upper side of the intake manifold. This is disadvantageous in practical use.

Support structure for intake system of internal combustion engine


A method for memory management, include allocating an empty page of a physical memory for reference data according to execution of an application program, and mapping the empty page to a virtual memory; checking a physical address of the physical memory to which the reference data has been loaded; mapping the checked physical address to the virtual memory to which the empty page has been mapped, and mapping the reference data; and releasing allocation of the allocated physical memory when the reference data is mapped to the virtual memory.

In a biological information study field, arithmetic calculations related to a sequence and the like of DNA, RNA, or protein are performed based on reference data. Such arithmetic calculations include target alignment and the like for checking an area having similarity in a functional, structural, and developmental relation between sequences, and several hundreds of MB to several TB of target data needs to be processed for one object according to the application thereof.
To the end, in a conventional art, when a typical memory management method is applied to a general purpose computer having a Von Neumann architecture, since characteristics of an application in which proximity data is classified into reference data and target data are not recognized, several tens of MB/s to several hundreds of MB/s of data input/output (IO) bandwidths are additionally required. The reference data indicates data with a size of about 3 GB to about 50 GB commonly used by a plurality of applications, and the target data indicates data with a size of about 70 GB to about 200 GB, which is to be subject to information processing.
Furthermore, when a plurality of corresponding applications are executed for one computer node, since it is not recognized that reference data is the same data dedicated for reading and a separate memory is allocated, a high memory cost is required. Furthermore, due to inefficient data management, an inefficient arithmetic calculation of a processor as well as a memory is performed.
For example, on the basis of reference data based on a character string indicating a nucleotide sequence or peptide sequence, applications for detecting SNP (Single-nucleotide polymorphism) of a target biological sequence perform a plurality of steps through pipe lines. In the implementation of all pipelines, data of about 780 GB is read and data of about 800 GB is generated. At this time, when a plurality of applications are executed, it is possible to reduce a time required to analyze all the pipelines by using data parallelism of a process level to the extent that pipeline dependency is not violated.

Method and apparatus for memory management

ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE


A virtual chassis system includes a plurality of network nodes connected by virtual fabric link (VFLs) that provide a connection for exchange of packets between the network nodes. A network node in the virtual chassis system is operable in a pass thru mode. In pass thru mode, the network node receives packets over a VFL and transparently forwards the packet over another VFL to another network node in the virtual chassis system. However, the network node 110 disables other port interfaces, such as port interfaces connected to external nodes from the virtual chassis system. The network node 110 in pass thru mode is operable to receive management commands over one or more VFLs and can still be managed through management commands.

1. Technical Field of the Invention
This invention relates generally to data networks and in particular to systems and methods for providing topological redundancy and resiliency between nodes of one or more data networks.
2. Description of Related Art
Data networks include various computing devices, for example, personal computers, IP telephony devices or servers that communicate with each other and/or with various other network elements or remote servers attached to the network. For example, data networks may comprise, without limitation, Metro Ethernet or Enterprise Ethernet networks that support multiple applications including, for example, voice-over-IP (VoIP), data and video applications. Such networks regularly include interconnected nodes, commonly known as switches or routers, for routing traffic through the network.
One of the key challenges faced by data networks is the need for network resiliency, i.e., the ability to maintain high availability despite eventual component failures, link failures or the like, which is critical to providing satisfactory network performance. Network resiliency may be achieved in part through topological redundancy, i.e., by providing redundant nodes (and redundant components within nodes) and multiple physical paths between nodes to prevent single points of failure, and in part through L2/L3 protocols to exploit the redundancy upon occurrences of failures to converge upon alternate paths for switching/routing traffic flows through the network. As will be appreciated, detection and convergence times must occur quickly (advantageously, in less than one second) in networks to achieve seamless transition to the alternate paths. Various types of network topologies are implemented within a network to provide redundancy between network elements, such as a ring networks, partial mesh networks, full mesh networks, hub networks, etc. Convergence times and redundancy between network elements often varies depending on the type of network typology implemented in a network.
Architectures of network elements also vary and affect network resiliency. For example, various node architectures include single switching elements, stackable switching elements, multi-slot chassis based network elements, etc. In general, depending on cost and network needs, one of these types of node architectures is selected and implemented into one of the types of network topologies. However, once implemented, it is sometimes difficult to upgrade or transition from one type of network topology to another type of network topology. It is also difficult to transition from one type of node architecture to another type of node architecture within a network topology or to incorporate various types of node architectures within one network.
Accordingly, there is a need for systems and methods for providing resiliency between nodes having one or more different types of node architectures in one or more different types of network topologies.

System and method for a pass thru mode in a virtual chassis system


The present disclosure concerns embodiments of a stair tread which can be installed on a staircase. The stair tread has a metal core at least partially covered with high-strength concrete. In an exemplary embodiment, the core portion has first and second horizontally extending metal plates that are spaced apart vertically from each other, and a grid of vertically extending metal support walls positioned between the first and second metal plates. The core portion can also include retention elements extending upwardly from and distributed across the top of the upper plate for securing the concrete covering to the core.

Typical concrete stair treads are very heavy and prone to brittle fracture, making them difficult to handle and install, adding significantly to the weight of a stair case, limiting their loading capacity when installed, and creating an earthquake safety hazard. These characteristics can be particularly problematic in multi-story buildings where weight problems are multiplied, and in commercial or industrial settings where ease of installation and safety are critical. Thus, there is a need for a stair tread that is lighter and stronger than conventional concrete stair treads that are currently available.


A fine particle producing apparatus includes a reaction chamber extending vertically from the lower side to the upper side; a material supply device which is connected to a central part on one end side of the vertically lower side inside the reaction chamber and supplies a material particle into the reaction chamber of a vertically upper side from a material supply port; a first electrode arrangement region which protrudes in an inward radial direction to be disposed on an inner peripheral wall in the reaction chamber which is vertically above the material supply device, and includes a plurality of lower electrodes to which AC power is applied; a second electrode arrangement region which protrudes in an inward radial direction to be disposed on an inner peripheral wall in the reaction chamber which is vertically above the first electrode arrangement region, and includes a plurality of upper electrodes to which AC power is applied; a collector which is connected to the other end side in the reaction chamber of the vertically upper side so as to collect fine particles; a power source which is capable of changing a frequency of AC power applied to at least one of the lower electrode included in the first electrode arrangement region and the upper electrode included in the second electrode arrangement region; and a controller which sets the frequency of AC power applied to the lower electrode as a frequency equal to or higher than a frequency of AC power applied to the upper electrode, in which a fine particle is generated from the material particle by generating arc discharge by the lower electrode and the upper electrode, and generating plasma in the reaction chamber.

In recent years, application of nanometer order fine particles to various devices has been studied. For example, metal fine particles of nickel are currently used for ceramic capacitors, and the use of fine particles having a particle diameter of 200 nm or less and good dispersibility has been studied for next-generation ceramic capacitors.
Furthermore, fine particles of silicon monoxide (SiOx:x=1 to 1.6) having a lower content of oxygen than that of silicon dioxide have been utilized as an evaporation material for an antireflection film of an optical lens or a gas barrier film for food packaging. Recently, it has been expected to be applied to a negative electrode material of a lithium ion secondary battery and the like.
General producing methods of these nanometer-order fine particles include a method of introducing a bulk material as a raw material together with beads such as ceramics or zirconia and fine pulverizing the material by mechanical pulverization, a method of melting and evaporating a material and injecting the material into air or water to obtain fine particles, or a method of obtaining fine particles in a chemical manner such as electrolysis or reduction. Among them, there is a method of producing fine particles in a gas phase utilizing thermal plasma (about 10000° C.) such as high frequency discharge, direct current, or alternating current arc discharge. A method of preparing fine particles in a gas phase utilizing this thermal plasma is very useful from the viewpoints that impurities (contamination) are small, the dispersibility of the produced fine particles is excellent, and synthesis of composite fine particles composed of plural types of materials is easy.
FIG. 4 is a schematic sectional view of a fine particle producing apparatus using thermal plasma of Conventional Example 1 as viewed from a direction perpendicular to a vertical direction. For the sake of convenience, one direction in a horizontal plane is defined as an x direction, and the vertically upper side is defined as a z direction.
Reaction chamber 101 is configured to include material supply device 110, a plurality of electrodes 104 for generating an arc discharge, a fine particle collector 103 for collecting produced fine particles 118, a gas supply pipe (not shown) for supplying gas to reaction chamber 101, a valve for adjusting pressure, and a pump 113 for exhausting gas. Arc discharge 116 which is the thermal plasma is generated by introducing argon gas from the gas supply pipe into reaction chamber 101, adjusting the pressure and then applying AC power from a plurality of AC power source 105 to a plurality of electrodes 104. Material particle 117 in material supply device 110 is introduced together with the carrier gas from the vertically lower side to generated arc discharge 116. Introduced material particle 117 is evaporated and vaporized by arc discharge 116, and rapidly cooled and solidified at the upper portion of reaction chamber 101 to produce fine particles 118. Produced fine particles 118 are introduced into fine particle collector 103 while resting on the gas flow in reaction chamber 101, and collected by a filter in fine particle collector 103.
Japanese Patent Unexamined Publication No. 2004-263257 is an example of the related art.

Fine particle producing apparatus and fine particle producing method

PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD.


An ink jet printing apparatus is provided which is capable of producing an image with a good balance between image quality and printing speed, without unduly shortening a longevity of a print head, even when an odd-numbered-pass bidirectional printing is performed. To this end, during a bidirectional multi-pass printing with a relatively small number of passes, a stepping mask is used to eliminate image problems caused by a difference in print permitted ratio between forward scan and backward scan. During a bidirectional multi-pass printing with a relatively large number of passes, a flat mask is used to give priority to suppressing density unevenness resulting from nozzle characteristic variations. As a result, the printing apparatus as a whole can produce an image with a good balance between image quality and printing speed, without unduly shortening a longevity of the print head.

1. Field of the Invention
The present invention relates to an ink jet printing apparatus and an ink jet printing method. More specifically it relates to a multi-pass printing method commonly employed in serial type printing apparatus.
2. Description of the Related Art
In recent years, relatively inexpensive office automation devices such as personal computers and word processors have come into widespread use. At the same time, efforts are being made to develop various types of printing apparatus that output information supplied from these devices and to enhance printing speed and print quality of these printing apparatus. Among others, a serial type ink jet printing apparatus is drawing attention as a relatively small printing apparatus capable of producing prints at low cost at high speed or with high quality. Such a serial type ink jet printing apparatus can perform a bidirectional printing to produce an image at high speed or perform a multi-pass printing to produce an image with high quality. Brief descriptions are made in the following as to the bidirectional printing and multi-pass printing in the serial type ink jet printing apparatus.
(Bidirectional Printing)
In a serial type ink jet printing apparatus, a print head having an array of ink drop ejection nozzles integrally formed therein is mounted in a carriage that is moved in a main scan direction in the printing apparatus. Individual nozzles (or ejection ports) of the print head eject ink according to image data as the carriage is moved, to form one band of image. A printing main scan (also referred to simply as a printing scan) of one band and an operation to convey a print medium corresponding to one band width are alternated repetitively to form an image on the print medium progressively.
The bidirectional printing is a printing method that, after completing a forward printing scan and the subsequent print medium convey operation, performs a printing scan in the backward direction without executing a back scan. Compared with a one-way printing that repeats the process of performing the back scan followed by the printing scan, the bidirectional printing can shorten the printing time. For example, suppose an entire area of the A4-size print medium is to be printed using a print head that has 64 nozzles arrayed therein at a density of 360 dpi (dots/inch) in the print medium convey direction. This requires about 60 printing scans. In that case, while the one-way printing requires about 60 reciprocal scans including back scans, the bidirectional printing needs only about 30 such reciprocal scans to complete the printing. This means the bidirectional printing can produce an image at almost twice the speed of the one-way printing.
(Multi-Pass Printing)
In a printing operation using a print head having a plurality of nozzles, the quality of an image produced is affected by ejection characteristics of individual nozzles. In a process of manufacturing nozzles of the print head, there inevitably occur some variations in the heating characteristics of electrothermal transducers (heaters) installed in the nozzles that generate ejection energy and also in the shape of ejection openings. These variations influence the ejection volume and direction of ink ejected from the nozzles, which in turn generates density unevenness and stripes in an image formed on a print medium.
FIGS. 1A-1C show a printing state of a print head that has no ejection characteristic variations. In the figures, reference number 201 represents a print head which, for the sake of simplicity, is shown to have only eight nozzles 202 here. As shown in FIG. 1A, if the sizes and the ejection directions of ink droplets 203 ejected from nozzles are aligned, an arrangement of dots formed on a print medium and a printed dot density distribution in the direction of nozzle array are uniform, as shown in FIG. 1B and FIG. 1C respectively.
FIGS. 2A-2C show a printing state of a print head that has ejection characteristic variations. The sizes and ejection directions of ink droplets ejected from individual nozzles 202 vary as shown in FIG. 2A. The dot arrangement on a print medium is also not uniform, as indicated in FIG. 2B. It is seen that there are some areas where dots overlap each other more than necessary and also blank areas where an area factor is less than 100%. As a result, the density distribution in the direction of nozzle array is uneven, as shown in FIG. 2C. These non-uniform areas, if repeated in the sub-scan direction, are recognized as density unevenness.
FIGS. 3A-3C show a printing state when a multi-pass printing is done using the print head of FIGS. 2A-2C. As shown in FIG. 3A, the multi-pass printing completes a printing operation on an area that in a one-pass printing can be printed in a single printing scan, by dividing the printing scan into a plurality of printing scans. Here is shown a 2-pass printing method.
FIGS. 4A-4C show an arrangement of dots printed by the individual nozzles in three consecutive printing scans. FIG. 4A shows dots printed in the first printing scan. Here is shown about half the number of dots to be printed in this area of print medium and they are arranged on alternate pixels in vertical and horizontal directions. After the first printing scan, the print medium is conveyed half the printing width of the print head (equivalent to 4 dots in this case) in the sub-scan direction. In the subsequent second printing scan the remaining half of the dots that are also arranged on alternate pixels are again printed (FIG. 4B). It is noted that they are printed at positions complementary to those dots printed in the first printing scan, i.e., they are printed where dots were not printed in the first printing scan. After another 4-dot conveying operation is finished, about half the dots are again printed in the third printing scan at positions complementary to those dots printed in the second printing scan (FIG. 4C). By repeating the above printing scan and the conveying operation alternately, an image is formed on the same image area (each unit image area) on a print medium by two printing scans of different parts of the print head.
The multi-pass printing described above prevents the dots printed by one nozzle from being connected in line in the main scan direction as shown in FIG. 2B. That is, the multi-pass printing allows the use of a print head equivalent to the print head 201 of FIG. 2A and can still halve adverse effects the ejection characteristic variations among the nozzles on the print medium image, with a resultant dot arrangement being as shown in FIG. 3B. As a result, the density distribution in the nozzle alignment direction is almost uniform as shown in FIG. 3C.
FIG. 7 is a schematic diagram for explaining a mask pattern capable to use for 2-pass printing and a completing relationship of it. P0001 denotes nozzle group consist of 8 nozzles for ejecting ink of same color. The nozzle group is divided into a first block and a second block each including 4 nozzles. P0002A and P0002B denote mask patterns corresponding to the first block and the second block respectively and each mask pattern has 4 pixels×4 pixels area. P0002A (lower pattern in FIG. 7) is a mask pattern used for a first scan, and P0002B (upper pattern in FIG. 7) is a mask pattern used for a second scan. Each mask pattern (P0002A and P0002B) consist of arrangement of print permitted pixels indicated by black and print non-permitted pixels indicated by white. Mask pattern P0002A for the first scan and Mask pattern P0002B for the second scan have completing relationship each other. Therefore, superimposing them, all of 4 pixels×4 pixels area is filled, and up to 100% printing become possible. Then, as such mask pattern is used repeatedly for the main scan direction, 2-pass printing becomes possible for all of area where the print head scans.
Next, the "print permitted pixel" and the "print non-permitted pixel" will be described. The "print permitted pixel" means a pixel in which a dot is permitted to be printed. That is, when a 2-value image data corresponding to the "print permitted pixel" indicates ejecting ink, a dot is printed to the pixel. And when the 2-value image data indicates not-ejecting ink, a dot is not printed to the pixel. On the other hand, the "print non-permitted pixel" means a pixel in which a dot is not permitted to be printed regardless of the 2-value image data. That is, even if the 2-value image data corresponding to the "print non-permitted pixel" indicates ejecting ink, a dot is not printed to the pixel.
P0003 and P0004 denote an arrangement of dots in an image which is completed by 2-pass printing. In the first scan, 2-valued image data generated by using mask pattern P0002A is printed by the first block. Then, the print medium is conveyed, in the direction of an arrow, by a distance corresponding to width of one block. In the following second scan, in a similar way, 2-valued image data generated by using mask pattern P0002A is printed by the first block. At the same time, in the second scan, 2-valued image data generated by using mask pattern P0002B is printed by the second block. In this way, a printing for an area corresponding to half of nozzle arraying region capable to be use in a 2-pass printing mode, is completed by 2 times printing scans.
Although in the above explanation dots have been described to be arranged at alternate pixels in both vertical and horizontal directions in each printing scan, the multi-pass printing is not limited to such a dot arrangement. The positions in which dot is printed in each printing scan are generally determined by an arrangement of print permitted pixels of the mask pattern described above. It is therefore possible to adjust the dot arrangement and the print ratios by changing the arrangement and ratio of print permitted pixel in the mask pattern. It is noted that, the "print permitted ratio" defined by a mask pattern is a ratio, which is expressed in percentage, of a number of print permitted pixels of a total number of the print permitted pixels and print non-permitted pixels in the mask pattern.
The 2-pass printing has been described in the above. The multi-pass printing may increase the number of passes to 2, 3, and 4 passes to enhance the uniformity of image quality. An increase in the number of passes, however, results in a reduction in the printing speed. So, many printing apparatus has a plurality of print modes with different number of passes, such as one that gives priority to image quality and one that places importance on printing speed. By using the bidirectional printing described earlier, it is possible to strike a balance between the image quality and the printing speed to provide a more appropriate print mode. It should, however, be noted that when a bidirectional multi-pass printing is performed using an odd number of passes in, a new problem that does not emerge in a multi-pass printing with an even number of passes arises.
FIGS. 5A and 5B are schematic diagrams showing a difference between an even-numbered-pass printing (with 4 passes) and an odd-numbered-pass printing (with 3 passes).
The bidirectional printing performs a printing operation in both the forward scan and backward scan. If the print heads for a plurality of inks are parallelly arranged in the main scan direction, the order in which the inks are applied to a print medium during the backward scan is reversed to that of the forward scan. For example, if during a forward scan inks are applied in the order of black, cyan, magenta and yellow, the backward scan applies inks in the order of yellow, magenta, cyan and black. At this time, even if the plurality of ink colors are ejected in the same percentages in both the opposite scans to produce the same image colors, there inevitably occurs some color difference between an image obtained in the forward scan and an image obtained in the backward scan. Further, if the printing is done using a single color or the print heads for a plurality of ink colors are arranged in the sub-scan direction, some printing characteristic differences, such as differences in dot shape resulting from satellite landing position variations, emerge between the forward scan and the backward scan. As a result, there are some density differences between images formed in the forward scan and the backward scan.
Thus, even where the multi-pass printing is performed, it is desired that there be no difference in the number of dots between the forward scan and the backward scan. Take FIG. 5A for example. In the case of an even-numbered-pass printing with four passes, the forward and backward scans are executed two times each for the same image area of a print medium which is corresponding to a conveying distance of the print medium between scan and scan. Therefore, if the each printing scans for the same image area is given a print permitted ratio of 25%, the total print percentage of the forward scans and that of the backward scans are both 50%.
However, in the case of 3-pass printing shown in FIG. 5B, the numbers of times that the forward scan and the backward scan are executed over the same image area of a print medium (corresponding to a conveying distance of the print medium between scan and scan) are not equal. Image areas printed by two forward scans and one backward scan and image areas printed by one forward scan and two backward scans are alternated in the sub-scan direction. That is, if the print permitted ratio for each printing scan is set at approximately-same, then image areas with a strong printing characteristic of forward scan where the number of dots printed by the forward scan is 33.3% more than that of the backward scan and image areas with a strong backward scan printing characteristic where the number of dots printed by the backward scan is 33.3% more than that of the forward scan, are formed alternately. Since colors and densities may differ between these two kinds of image areas, overall image impairments such as color unevenness and density unevenness are likely to occur.
As to the bidirectional printing with an odd number of passes, Japanese Patent Laid-Open No. 2000-108322 discloses a construction in which a print permitted ratio is differentiated according to nozzle positions in the print head in order to make the sum of print permitted ratio in forward scans and the sum of print permitted ratios in backward scans equal.
FIG. 6 is a schematic diagram showing print permitted ratios of forward scans and backward scans in 3-pass bidirectional printing disclosed in Japanese Patent Laid-Open No. 2000-108322. According to this patent document, a nozzle array of the print head is divided into three blocks, with both side blocks used in a first pass and a third pass for a same image area assigned a print permitted ratio of 25% each and a central block used in a second pass assigned a print permitted ratio of 50%. With this, areas printed by forward scan followed by backward scan followed by forward scan and areas printed by backward scan followed by forward scan followed by backward scan can both have equal numbers of dots capable to be printed by the forward scans and the backward scans.
In the following, a mask pattern in which the print permitted ratio of at least one scan is different from that of other scans, as described with FIG. 6, is referred to as a stepping mask. On the other hand, a mask that sets print permitted ratio of different scans substantially equal, such as shown in FIGS. 5A and 5B, is referred to as a flat mask.
With the above stepping mask, it is possible to produce a uniform printed image with no color unevenness or density unevenness even when an odd-numbered-pass printing is performed.
When the stepping mask is used, however, a difference of printing frequency is arisen among nozzles. So, if any nozzle greatly differing in ejection volume and ejection direction from other should be included in the neighboring nozzles having high, frequency of use the ejection characteristics of that nozzle is easily recognized on a printed image. That is, the use of the stepping mask may pose a risk of eliminating the advantage the multi-pass printing is intended to produce—that of "alleviating the adverse effect of image due to ejection characteristics of individual nozzles".
Another problem in using the stepping mask is that the print head longevity may be reduced by a shortened life of a nozzle having a high frequency of use.

Ink jet printing apparatus and ink jet printing method


There is provided a laminated body that includes a metal layer comprising an electroconductive metal layer and a metal oxide layer disposed on each side of the electroconductive metal layer; and a resin layer or an elastic layer disposed on at least one side of the metal layer. There is also provided a producing method of the laminated body. Furthermore, there is provided a fixing belt and an image forming device.

1. Technical Field
The invention relates to a laminated body and a producing method thereof, and a fixing belt, a fixing device and an image forming device.
2. Related Art
In an electrophotographic image forming device that uses a dry toner, a fixing device that heats and pressurizes a toner image to fix the toner image on a surface of a recording medium has conventionally been provided with a fixing roll in which a toner releasing layer is disposed on an outer periphery surface of a metal core bar and a halogen heater for heating is disposed inside of the metal core bar.
In a fixing device or an image forming device that uses an endless belt, when the endless belt is bent to have a large curvature, the endless belt can be disposed within a limited space. Furthermore, in the case of the endless belt being used as a fixing belt, when the endless belt is bent to have a large curvature, a recording medium, conveyed to a contact portion formed by the endless belt and a pressure member that is pressed against the endless belt, can be excellently peeled off the endless belt.

Laminated body and producing method thereof, fixing belt, fixing device and image forming device


This invention is a demultuplexer consisting on a sequential division of the data stream in a series of Sagnac interferometer amplitude modulators (SIAMs), wherein each modulator in the series is driven by a single microwave frequency derived directly from a radio frequency (RF) data rate clock, with the RF phase properly adjusted to extract a channel of interest.

1. Field of the Invention
This invention pertains generally to data multiplexers and more specifically to a Sagnac interferometer amplitude modulator based demultiplexer for high-speed return-to-zero optical time division multiplexed data.
2. Description of the Related Art
Due to the speed limitations of electronic circuitry, future time division multiplexed optical communications networks operating at data rates in the order of 100 Gbits/s will require optical demultiplexing techniques. Toward this end, a variety of all-optical demultiplexing schemes, based on third order nonlinearities in fiber or on resonant nonlinearities in semiconductors, have been proposed and demonstrated. These require a local optical clock to drive the demultiplexing; furthermre, many (those based on nonlinearities in fiber) suffer from a long latency between receipt and decoding of the data.
Modulator based demultiplexing schemes have been previously proposed, and demonstrated with speeds up to 40 Gbit/s. These have depended on Mach-Zehnder lithium niobate intensity modulators, which are well known to suffer from bias instability with changes in environmental conditions and applied voltage.
The standard integrated optic intensity modulator consists of a channel microwave Mach-Zehnder interferometer fabricated on a lithium niobate substrate. The Mach-Zehnder interferometer consists of an input waveguide which branches to a pair of parallel optical waveguides (a"Y-branch"), at least one of which is positioned under an electrode so that its optical path length may be varied by an applied voltage, via the electro-optic effect. The two waveguides are combined at the output(at a second Y-branch, oriented to combine the light in the two waveguides), where the light interferes according to the differential optical phase imposed by the applied voltage. However, the tolerances involved in the fabrication of the input and output Y-branches restrict the ON/OFF extinction ratio to .about.20 dB. This is due both to the splitting ratio between the two arms being other than 50%, and to the fact that the splitting ratios of the two branches are typically unequal.
The problem of bias drift is ubiquitous with Mach-Zehnder modulators. The phenomenon stems from fundamental material properties of the LiNbO.sub.3 substrate, in combination with the topology of the Mach-Zehnder interferometer. The transfer function of a Mach-Zehnder interferometer (or indeed any interferometer) depends on the optical path length difference (differential phase) between its two arms as a squared-sinusoid. Since the two optical paths in the Mach-Zehnder interferometer are independent, the differential phase between them in the absence of an applied voltage is arbitrary. For effective modulation, a specific initial phase is required; in Mach-Zehnder devices, this is accomplished by applying a direct current (DC), or bias, voltage in addition to the alternating current (AC) modulation. However, the LiNbO.sub.3 substrate is a piezoelectric, electro-optical material, with a small but significant electrical conductivity. Thus, the substrate transduces the applied bias voltage and changes in a variety of environmental conditions (including temperature, mechanical stress, humidity) into an optical path length difference between the two interferometer arms which varies in time. This is the bias drift which must be tracked with compensating electronic feedback to the applied DC voltage for the modulator to operate at a fixed bias phase.
Optical time division multiplexing (OTDM) is a technique for transmitting data over optical fibers at very high data rates (e.g., 100 Gbit/s) by temporally interleaving multiple slower rate (e.g., 10 Gbit/s) data streams. This technique allows access to the virtually unlimited bandwidth of the optical fiber transmission medium, despite the fact that the electronics used to generate and encode the data are relatively narrowband.
The multiplexing (MUX) process is the conversion of relatively slow speed parallel data streams to a single very high speed serial stream. While it is relatively trivial to construct a high speed OTDM data stream, decoding that data once it reaches its destination is much more difficult. The data speed is well beyond the capabilities of electronics, either at present or in the foreseeable future. In order to decode the data, some means is required for extracting a single low speed data channel from the high speed stream, or, more generally, for converting the high speed serial data back into the several lower speed parallel channels. This process is known as demultiplexing (DMUX). Over the past few years, a number of schemes have been demonstrated capable of demuliplexing 100 Gbit/s data. These have universally relied on using some optical correlation scheme, wherein a local optical clock signal is combined with the incoming optical data stream in a nonlinear optical medium. Examples include four-wave mixing and cross-phase modulation in optical fiber and semiconductor laser amplifiers.
All of these techniques rely on an optical clock signal, consisting of a high peak power pulsed laser with a repetition rate equal to the data rate of the individual channels. Generating this optical clock stream adds a great deal of complexity and expense to the demultiplexing process. Furthermore, the previously demonstrated schemes are capable of demultiplexing only a single data channel, so that as many demultiplexers as there are TDM data channels would be required to decode the entire data stream. The nature of the optical nonlinearities involved normally dictate that the optical clock consist of a stream of short (e.g., 1-3 ps), high peak power (1-10 W) pulses of light. An example of such a demultiplexer is the polarization multiplexed nonlinear optical loop mirror (NOLM DEMUX) developed by the Naval Research Laboratory. See, Dennis et al., SOLITON LOOP MIRROR DEMULTIPLEXER USING ORTHOGONALLY POLARIZED SIGNAL AND CONTROL, Photon. Technol. Lett Vol. 8, No.7, pp. 906-908, 1996. The optical nonlinearity is the Kerr effect (cross phase modulation) in optical fiber, which is extremely weak. The optical clock in this device consists of an actively mode locked fiber laser using a high power optical amplifier with feedback stabilization to maintain suitable operation. This clock is extremely expensive and would be prohibitive if such a device were required at every node in a network where demultiplexing is required.. The weak nonlinearity in optical fiber dictates that very long lengths (e.g., 5-10 km) be used to obtain sufficiently efficient switching, even with the high peak power optical clock sources. This introduces a substantial delay (20-25 .mu.s) between the arrival and decoding of the data by the receive node.
Demultiplexing schemes based on optical nonlinearities in fiber or in semiconductors can demultiplex the full stream only by demultiplexig each of the channels in parallel. To accomplish this, copies of the full input stream must be split off, one for each base rate channel, and sent to separate identical demultiplexers tuned for the individual channel.

The United States of America as represented by the Secretary of the Navy


A hydraulic system for an automatic gearbox for a motor vehicle, includes a high-pressure circuit which includes a pressure accumulator, at least one clutch and actuators, and a low-pressure circuit for cooling the clutch, the high-pressure circuit and the low-pressure circuit each containing a hydraulic cooling pump and a hydraulic charging pump that can be driven by a shared electric motor; and a controller which, when it is detected that the pressure accumulator needs to be charged, controls the electric motor to run at a charging setpoint speed, and/or, when it is detected that cooling is needed or another need exists, controls the electric motor to run at a cooling setpoint speed or another setpoint speed. When the pressure accumulator does not need to be charged and there is no need for cooling and no other need, the controller reduces the setpoint speed to zero for a specified period. At the end of the period the controller controls the electric motor to run at least at the test speed.

The invention relates to a hydraulic system for an automatic transmission, in particular a dual-clutch transmission, of a motor vehicle, a motor vehicle with such a hydraulic system and a method for operating such a hydraulic system.
In a dual-clutch transmission gears can be changed fully automatically by means of two sub-transmissions. Torque transmission is accomplished via one of two clutches, which connects the two sub-transmissions with the drive. The clutches and the actuators for engaging the gears can be hydraulically actuated by means of a hydraulic system.
From DE 10 2011 100 836 A1 a generic hydraulic system is known which forms the starting point of the present invention. The present invention relates in particular to program modules, which are required for a signal processing of the actual current consumption of the pump drive in the hydraulic system. By means of this signal processing it is recognized whether or not a requirement for charging the pressure accumulator exists.
The hydraulic system known from DE 10 2011 100 836 A1 is divided into a high-pressure circuit and a low-pressure circuit. In the high-pressure circuit a pressure accumulator is provided with which a strongly temperature-dependent accumulator pressure can be provided in the range of for example about 30 bar. In addition the hydraulically actuatable clutches and actuators (for example gear shift elements) are arranged in the high-pressure circuit. On the other hand the low-pressure circuit operates at a hydraulic pressure in the range of for example about 5 bar. The cooling of the sub-transmissions is accomplished by means of the low-pressure circuit via the hydraulic fluid.
In the generic hydraulic system the low-pressure circuit has a cooling hydraulic pump and the high-pressure circuit has a charging hydraulic pump with which the pressure accumulator is charged to the required accumulator pressure. The two hydraulic pumps are driven via a common drive shaft by means of a shared electric motor. The electric motor is controlled by a control device. When recognizing a requirement for charging the pressure accumulator, the electric motor is controlled to run at a charging setpoint speed. As an alternative and/or in addition the electric motor is controlled to run at a cooling setpoint speed when for example recognizing a requirement for cooling. In addition the high-pressure circuit and the low-pressure circuit can be connected via a bypass line with integrated control valve. The control valve can be switched between a charging position and a non-charging position (cooling position) without external energy input, i.e., automatically, in dependence on the accumulator pressure in the high-pressure circuit. In the charging position the hydraulic system operates in the charging mode (i.e., the charging hydraulic pump is fluidly coupled with the high-pressure circuit) and at high pump load with correspondingly high actual current consumption. In contrast, in the non-charging position (i.e., in the cooling position) of the control valve, the hydraulic system operates for example in a cooling mode or in another mode for example a filter-cleaning mode.
For reasons of clarity the following discussion mostly refers to the cooling position of the control valve. It is noted that the cooling position and the non-charging position of the control valve are identical. In addition for reasons of clarity the following discussion mostly uses the terms cooling mode and cooling speed. The cooling mode is merely an example for a non-charging mode and hence the term cooling mode can be replaced with the more general term non-charging mode.
In the cooling position of the control valve the charging pump, beside the cooling pump, is also fluidly connected with the low-pressure circuit and decoupled from the high-pressure circuit. In the cooling mode the hydraulic pumps operate—in contrast to the charging mode—at a lower pump load with correspondingly lower actual power consumption.
In the state of the art a requirement for charging the pressure accumulator is detected via a sensor, for example a pressure sensor arranged in the high-pressure circuit. As soon as the accumulator pressure falls below a predetermined lower threshold value the above-mentioned control valve automatically assumes its charging position. In addition the control device recognizes the requirement for charging the pressure accumulator by means of the sensor. When recognizing the requirement for charging the pressure accumulator, the control device controls the common electric motor to run at the charging setpoint speed, thereby charging the pressure accumulator in the high-pressure circuit. As soon as the accumulator pressure exceeds an upper threshold value, the above-mentioned control valve automatically assumes its cooling position. In addition the control device recognizes by means of the sensors that a requirement for charging the pressure accumulator no longer exists.
The arrangement of a sensor (for example a pressure sensor or valve position sensor) in the high-pressure circuit for recognizing a requirement for charging the pressure accumulator increases component costs. In addition the operation of the pressure sensor may be subject to malfunctions.

Method for a hydraulic system for a dual-clutch gearbox


A sound image control system which is able to concurrently perform sound image localization control for two persons is provided. The sound image control system controls a sound image localization position by reproducing an audio signal from a plurality of loudspeakers. The sound image control system includes at least four loudspeakers for reproducing the audio signal and a signal processing section. The signal processing section sets four points corresponding to both ears of two listeners as control points, and performs signal processing for the audio signal input into the plurality of loudspeakers so that two target sound source positions indicating sound image localization positions of the respective two listeners are set in the same direction with respect to the two listeners. The two target sound source positions are set so as to satisfy the following condition, T1=T2≦T3<T4.

1. Field of the Invention
The present invention relates to a sound image control system, and more particularly, to a sound image control system controlling a sound image localization position by reproducing an audio signal from a plurality of loudspeakers.
2. Description of the Background Art
In recent years, a multichannel signal reproduction system typified by a DVD has become prevalent. However, housing conditions often do not allow for the installation of five or six loudspeakers. Therefore, a sound image control system using a so-called virtual reproduction method, which realizes virtual reproduction of a surround signal with Lch and Rch loudspeakers, has been developed.
Also, especially in a sound image control system for car audio equipment, the placement of loudspeakers in a narrow inside space of a vehicle is limited due to considerable influences of reflection, reverberation, and standing waves. In such an arrow space as the inside of a vehicle, it is conventionally rather difficult to freely localize a sound image. However, there is still a strong demand to localize vocals, etc., included in music in the front center of a passenger. In order to satisfy the above-described demand, a sound image control system as described below is in the process of being developed.
Hereinafter, with reference to a drawing, the conventional sound image control system is described. FIG. 47 is an illustration showing the structure of the conventional sound image control system. In FIG. 47, the sound image control system installed in a vehicle 601 includes a sound source 61, a signal processing section 62, an FR loudspeaker 621 placed on the right front door of the vehicle 601, and an FL loudspeaker 622 placed on the left front door of the vehicle 601. The signal processing section 62 has control filters 63 and 64.
An operation of the sound image control system shown in FIG. 47 is described below. A signal from the sound source 61 is processed in the signal processing section 62, and reproduced from the FR loudspeaker 621 and the FL loudspeaker 622. The control filter 63 controls an Rch signal from the sound source 61, and the control filter 64 controls an Lch signal from the sound source 61. The signal processing section 62 performs signal processing so that sound from the FR loudspeaker 621 is localized in a position of a target sound source 631 and sound from the FL loudspeaker 622 is localized in a position of a target sound source 632. Specifically, the control filters 63 and 64 of the signal processing section 62 are controlled as follows. That is, assume that a center position (a small cross shown in FIG. 47) of a listener A is a control point, a transmission characteristic from the FR loudspeaker 62 to the control point is FR, a transmission characteristic from the FL loudspeaker 622 to the control point is FL, a transmission characteristic from the target sound source 631 to the control point is G1, and a transmission characteristic from the target sound source 632 to the control point is G2, characteristics HR and HL of the respective control filters 63 and 64 in the signal processing section 62 are represented by the following expressions.HR=G1/FRHL=G2/FL
The characteristics (HR and HL) satisfying the above-described expressions allow the FR loudspeaker 621 to be controlled so as to reproduce sound in the position of the target sound source 631, and the loudspeaker 622 to be controlled so as to reproduce sound in the position of the target sound source 632. As a result, a center component common to the Lch signal and the Rch signal is localized between the virtual target sound sources 631 and 632. That is, the listener A localizes a sound image in a position of a front target sound source 635.
However, the conventional system shown in FIG. 47 has only one control point. As a result, the difference between the right and left ears, which is the mechanism of perception, is not controlled, thereby having a limited sound image localization effect. Furthermore, most sound image control systems in practical use only correct a time lag between the FR loudspeaker 621 and the FL loudspeaker 622, thereby not actually realizing the virtual target sound sources 631 and 632.
As a sound image control system for home use, on the other hand, a sound image control system performing sound image control by setting both ears as control points has been developed. However, in the above-described sound image control system, the number of control points is assumed to be two, that is, both ears of a single listener are assumed to be the control points. Therefore, the above-described sound image control system does not concurrently perform sound image control for both ears of two listeners.

Matsushita Electric Industrial Co., Ltd.


In an electronic apparatus having a plurality of printed boards or modules, an on-line module replacement system for allowing the desired of the boards to be inserted or removed while maintaining connecting lines alive allows a plug-in package to be mounted to a backboard without affecting the power supply voltage of other packages. This can be done without resorting to an inductance or similar impedance part heretofore included in a plug-in package.

The present invention relates to an electronic apparatus having a plurality of printed boards or modules and, more particularly, to a system for allowing the desired one of the modules to be mounted or dismounted to or from the apparatus while maintaining connecting lines alive.
Japanese Patent Laid-Open Publication No. 51-108520, for example, discloses in its FIG. 3 an arrangement for protecting the power supply voltage of a plug-in package from noticeable variation by use of the system of the kind described. In this arrangement, a current is fed from an outside power source to a plug-in package via a connector. The current is applied to an electronic circuit built in the package via an impedance and an inductance. The impedance and inductance reduce a rush current and thereby reduce the variation of the power source voltage. However, this kind of scheme is not practicable without resorting to the impedance and inductance. When the electronic circuit is of the kind consuming great power, the impedance and inductance are necessarily implemented as bulky parts which obstruct the effective mounting of the package.


First apparatuses (10) such as tags and batches comprise receivers (11) for receiving ultrasonic signals (1) comprising first codes from sources (27, 30), analyzers (12) for analyzing first codes, transmitters (13) for transmitting electromagnetic signals (2) comprising second codes to second apparatuses (20), and controllers (14) for, in response to analysis of first codes, controlling at least parts of the first apparatuses (10), such as modes, transmissions, and supplies of second codes. Second apparatuses (20) such as parts of interfaces and parts of stations comprise receivers (21) for receiving the electromagnetic signals (2) comprising second codes from the first apparatuses (10), analyzers (22) for analyzing second codes, and generators (23) for, in response to analysis of second codes, generating parameter signals (5) defining issues like registration issues and authorization issues and environmental issues, and analysis results. The first apparatuses (10) may form part of first devices (100) such as mobile phones and organizers, and the second apparatuses (20) may form part of second devices (200) such as interfaces and stations.

U.S. Pat. No. 7,362,656 B2 discloses an ultrasonic locating system. This system uses transmission units (sources) for transmitting different encoded ultrasonic pulses. The system further uses a tag (first apparatus) for receiving the different encoded ultrasonic pulses and for transmitting radio signals. These radio signals comprise calculated arrival times for the received ultrasonic pulses and comprise tag identifications. The system also uses a server (second apparatus) for receiving the radio signals and for updating its database. This system is designed for a purpose of determining a location of a tag.

Ultrasonic transmission / reception for electromagnetic transmission reception


A pneumatic hammer drill includes: a pneumatic cylinder having a cylinder rear end fitted in a handle body, an air passage, and a pressure chamber; and an air valve adjacent to the cylinder rear end. The air valve has a front bearing end, a valve orifice interconnecting fluidly the air passage and the pressure chamber, and an opening disposed at the front bearing end in communication with the valve orifice. A piston is disposed slidably in the pressure chamber, and has a piston rear end capable of moving towards or away from the front bearing end. An air trap arrangement is associated with the piston rear end and the front bearing end to trap air between the same and around the opening so as to provide a shock-absorbing air cushion when the piston rear end moves towards the front bearing end.

1. Field of the Invention
The invention relates to a pneumatic hand tool, more particularly to a pneumatic hammer drill.
2. Description of the Related Art
Referring to FIGS. 1 and 2, a conventional pneumatic hammer drill includes a handle body 10, a pneumatic cylinder 12, an air valve 13, and a tool 14. The handle body 10 defines a cavity 111 at an upper portion thereof, and has a lower handgrip portion 11. The pneumatic cylinder 12 is fitted into the cavity 111, and includes an externally threaded front end 1213 extending outwardly from the cavity 111, a spring element 122 engaged threadedly to the front end 1213, a pressure chamber 1211, a piston 123 inserted slidably into the pressure chamber 1211, and an air passage 1212 in fluid communication with the pressure chamber 1211 and the air valve 13. Highly compressed air is introduced into the air passage 1212 via the lower handgrip portion 11. The spring element 122 has a limiting end 1221 extending outwardly and curvedly from a front end thereof.
The air valve 13 is disposed in the cavity 111 adjacent to the pneumatic cylinder 12, and includes a front valve casing 131, a rear valve casing 132, a diaphragm 133, and a plurality of positioning pins 134. The front valve casing 131 is provided with a valve orifice 1311 to permit air flow therethrough, and a plurality of positioning holes 1312 around the valve orifice 1311. The rear valve casing 132 is provided with a valve orifice 1323, a valve seat 1321 disposed around the valve orifice 1323 and receiving the diaphragm 133 therein, and a plurality of fixing holes 1322 around the valve seat 1321. The positioning pins 134 interconnect the front and rear valve casings 131, 132, and have front ends inserted respectively into the positioning holes 1312 in the front valve casing 131, and rear ends inserted correspondingly into the fixing holes 1322 in the rear valve casing 132, thereby aligning the holes 1312, 1322 in the front and rear valve casings 131, 132.
The tool 14 has an annular protrusion 142 proximate to a rear portion 141 thereof and located between a front end face of the pneumatic cylinder 12 and the limiting end 1221 of the spring element 122.
The compressed air flows through the valve orifices 1311, 1323 from the air passage 1212 in the pneumatic cylinder 12, and enters a rear side of the pressure chamber 1211 so as to push forwardly the piston 123, which in turn, strikes the tool 14 so that the tool 14 produces a hammering force on a workpiece. The tool 14 cannot be released from the pneumatic cylinder 12 as the annular protrusion 142 thereof is engaged with the limiting end 1221 of the spring element 122. When the compressed air enters a front side of the pressure chamber 1211 via the air passage 1212, the piston 123 is pushed rearwardly toward the front valve casing 131 so that the tool 14 is restored to its original position through a restoring force of the spring element 122. Hence, by moving the piston 123 reciprocatingly in the pressure chamber 1211 through such supply of the compressed air, a hammering action of the tool 14 is effected.
Although the aforementioned conventional pneumatic hammer drill can achieve its intended purpose, it has many drawbacks. Firstly, since a front end face of the front valve casing 131 and a rear end face of the piston 123 are generally flat, and since the impact of the piston 123 against the front valve casing 131 is strong when the compressed air pushes the piston 123 rearwardly toward the front valve casing 131, internal components of the hammer drill are prone to damage over time. Further, because of the strong impact force, an operator's hand is easily fatigued and may even become injured. Moreover, the strong impact produces a loud noise which is unpleasant and may even adversely affect the sense of hearing of the operator. Additionally, the positioning holes 1312 in the front valve casing 131 must be aligned with the fixing holes 1322 in the rear valve casing 132 and at the same time with the air passage 1212 in the pneumatic cylinder 12 so as to permit air flow into the air valve 13. However, since such alignment is not easily achieved, overall assembly of the conventional hammer drill is made complicated.


A camera system includes an image sensor, a stop aperture, an infrared cut filter disposed between the image sensor and the stop aperture, and a lens assembly. The lens assembly has a field of view ranging between 80 degrees and 110 degrees and is disposed between the infrared cut filter on an image side of the lens assembly and the stop aperture on an object side of the lens assembly. The lens assembly includes six lenses. Four of the six lenses have positive optical power and two of the six lenses have negative optical power. The six lenses include first, second, third, fourth, fifth, and sixth lenses having first inline, second inline, third inline, fourth inline, fifth inline, and sixth inline relative positions, respectively, along an optical path through the lens assembly.

Conventional digital imaging devices or cameras often include a lens assembly (which includes multiple lens elements) that focuses image light onto an image sensor that measures the image light and generates an image based on the measurements. FIG. 1 illustrates a common configuration for a digital imaging device 100, which includes an image sensor 110 and a lens assembly 115 including multiple lens elements 120. Lens assembly 115 is disposed over image sensor 110 to focus image light 125 from an object onto the pixels of image sensor 110. Lens assembly 115 may include convex and/or concave lens elements 120 that together give lens assembly 115 an effective focal length ("EFL"). The lens assembly 115 also provides a certain Depth of Field ("DOF"). DOF refers to the range of distances in the field of view of an image sensor that appear to be well focused in an image captured by image sensor 110. The Field of View ("FOV") of lens assembly 115 refers to the angular extent that is viewable through lens assembly 115 at a given moment.
Lens assembly 115 has a z-axis height H1, which is also referred to as the optical total track length ("TTL"). The optical TTL is typically influenced by the FOV and the size of image sensor 110, as well as other design choices. A larger optical TTL may limit the applications or uses of digital imaging device 100 because of space constraints. Therefore, a lens assembly that allows a digital imaging device to capture high resolution images with a large FOV while reducing the optical TTL can be advantageous.