Device for transmitting light at variable intensity, the device including a front variable polarizer, polarizing incoming light at a first selected polarization level, in a first direction and a rear variable polarizer, optically coupled with the front variable polarizer, polarizing light exiting the front variable polarizer at a second selected polarization level, in a second direction, wherein the first selected polarization level and the second selected polarization level are substantially zero, when no substantial electric power is applied respectively, to the front variable polarizer and the rear variable polarizer.

Systems and methods for varying the transmittance or reflectance of light are known in the art. Such systems are employed in automotive rear-view or side-view mirrors, automotive windows, spectacles, head-up displays (HUD), head-mounted displays (HMD), and the like.
Conventional automotive rear-view mirrors have a constant reflectance. Hence, a sudden increase in luminance, for example when the image of the headlamps of a vehicle approaching from behind is reflected toward the driver through the rear-view mirror, may temporarily blind the driver. This is especially disturbing during poor environmental lighting conditions, when the eyes of the driver have become accommodated to the reduced background luminance. In conventional viewing glasses, motorcycle or ski goggles, automotive windows, and the like, the operator is frequently exposed to excessive sun light, which may cause discomfort and even eye damage.
In HUD and HMD systems, the displayed information includes symbols, graphical or alphanumeric image components. Displaying this information on the field of view of the pilot, considerably reduces the physical tasks required during the flight, such as checking the flight instruments, aiming toward a target, landing, and the like. Similarly, in cameras or other visor assisted devices, assisting data (e.g., aiming, pointing, focusing or zooming data, exposure time, lens stop data, and the like) are superimposed on the external field of view. The operator of such devices should be able to perceive both the displayed data and the background view, without moving his eyes or head between the display and the outside scene. In conventional HUD and HMD, the background scene, which is illuminated by sunlight, is often of a very high luminance, up to several thousands of foot-Lamberts (fL), and furthermore, direct sunlight has a luminance even several orders of magnitude larger.
The term "contrast" herein below refers to the ratio of the luminance of two images at a certain viewing plane. When an image is displayed on a background scene, the contrast is equal to the ratio between the luminance of the displayed image and the sum of the luminances of the displayed image and the background scene. The higher the luminance of the background scene, the lower the contrast of the displayed image against the background scene. For example, the contrast of a displayed image having a luminance of 500 fL, which is displayed against a background scene having a luminance of 4000 fL, is about 11%. However, the same displayed image would have a contrast of about 40%, if displayed against a background scene having a luminance of 800 fL.
Hence, in such situations it is desirable to reduce the luminance of the background scene. Different techniques have been applied or proposed, for reducing the background luminance. One such technique employs a mechanism for switching between a plurality of fixed states, such as commonly applied in automotive rear-view mirrors. Other techniques employ a fixed, transparent light filter, similar to that used in sunglasses or sun visors, or a fixed opaque shield for reducing the viewing aperture, such as sun blinds. However, these devices reduce the visibility of the background scene under poor illumination.
Another technique for reducing background luminance employs auto-dimming mirrors (ADM) or variable transmittance optics (VTO) with real-time adaptive reflectance and transmittance, respectively. Mirrors or viewing glasses according to these techniques, exhibit variable reflection or transmission, respectively, whereby they can be manually or automatically switched to a dark state or a bright state, or switched between a plurality of intermediate states, which may either be continuous or discrete. The dark state, also referred to as the closed state, is the state of minimal transmittance or reflectance. The bright state, also referred to as the open state, is the state of maximal transmittance or reflectance.
Conventional ADM devices, according to one technique, include a VTO component, and a highly reflective surface. Light incident upon such a device, passes through the VTO component and is reflected by the reflective surface back to the VTO component, whereby the amount of light eventually reflected from the device depends on the state of the VTO component.
Electro-optic ADM and VTO devices may be either normally open (also referred to as normally bright), meaning they are in the open state when no electric field is applied, or normally closed (also referred to as normally dark), meaning they are in the open state when an electric field is applied. Normally open devices have the property that in case of power failure, the device continues to transmit or reflect the incident light, without substantially affecting the incident light. It is noted that this property may be critical in human eye related applications, such as automotive rear-view mirrors or windows, wherein the driver has to be able to view the images through the device, at all times. The contrast ratio, also referred to as the dynamic range, is equal to the ratio of the maximal and minimal obtainable transmittance or reflectance values of the VTO or ADM device, respectively.
VTO and ADM techniques have employed various elements, such as photochromic (PhC) materials, electrochromic (EC) cells, suspended particle technology and conventional liquid crystal (LC) technology. PhC materials have a limited spectral and photochemical sensitivity. Hence, devices using these materials are highly dependent on the incidence of strong ultraviolet illumination thereupon.
EC and SP cells have relatively large response times, typically in the order of seconds to minutes, and hence, they are not normally employed in rapidly-changing illumination conditions. Furthermore, EC materials exhibit a memory effect in their dark state, and hence, devices employing these materials require a special reverse drive circuit in order to return to the transparent default state. SP cells are normally dark by nature, and hence are applicable only to normally dark devices.
There are several conventional ADM and VTO techniques which employ the LC technology. A device, according to one such technique, includes an LC pane sandwiched between two crossed polarizers. The transmittance of the device depends on the state of the LC pane, which may be controlled by an electric field applied thereto. However, a polarizer absorbs at least 50% of unpolarized incident light, thereby determining the open state transmittance to be no more than 50%.
U.S. Pat. No. 5,015,086 issued to Okaue et al., and entitled "Electronic Sunglasses", is directed to electronically controlled sunglasses utilizing conventional LC technology and powered by a solar cell. According to embodiment 1 of the disclosure, the LC panel used has a film substrate including an electrode surface and a nematic liquid crystal having a proper amount of right-spinning chirality material. Light-polarizing plates are pasted on both sides of the film substrate, with the absorption axes of these light-polarizing plates matching the rubbing direction of the film substrate. The maximal transmittance of the transmittance varying section is 35%.
Another technique which employs LC technology, alleviates the polarizer dependent light loss by using dichroic or pleochroic guest-host liquid crystal (GH-LC) mixtures, whereby no polarizers are needed. Devices according to these techniques, especially those with normally open cells, have generally yielded poor contrast ratios.
U.S. Pat. No. 4,660,937 issued to Richardson, and entitled "Dichroic Dye-Nematic Liquid Crystal Mirror", is directed to an auto-dimming mirror, which utilizes a liquid crystal containing a dichroic dye. The auto-dimming mirror includes a liquid crystal material enclosed by a seal, a reflective surface, an electrically conducting layer and transparent front and back members on each side of the liquid crystal material. The auto-dimming mirror may be either normally open or normally closed, depending on whether the liquid crystal has positive or negative anisotropy and whether the dichroic dye is positive or negative. The dynamic range reported was about 3.7 for the normally closed embodiment, and about 1.3 for the normally open embodiment.
U.S. Pat. No. 6,239,778 issued to Palffy-Muhoray et al., and entitled "Variable Light Attenuating Dichroic Dye Guest-Host Device", is directed to a VTO cell which utilizes a host material and a light absorbing dichroic dye guest. A solution of dichroic dye and a liquid crystalline material is disposed between two transmissive substrates, whose inner surfaces are coated with an electrically conducting layer. Each side of the VTO cell further includes an alignment layer and a passivation or insulating layer. The electrically conducting layers are connected to a power circuit, which includes a variable voltage supply controlling the transmittance of the cell.
European Patent Application Publication No. EP1158336A2 to Weiss et al., and entitled "System and Method for Varying the Transmittance of Light Through a Media", discloses a system and method for varying the transmittance through selected portions of a media, on which images are displayed. The system includes a VTO media made of a non-conventional LC material, such as a dichroic dye GHLC. In one embodiment of the disclosed system, a double cell configuration is applied. Accordingly, two VTO cells are applied, which have mutually perpendicular LC director orientations, thereby effectively behaving as two crossed polarizers when no voltage is applied. When a voltage is applied, each of the cells switches to a homeotropic phase, with the director orientation perpendicular to the cell surface, thereby minimizing the dichroic dye absorption. Thus, the double-cell configuration may be used for a normally closed VTO cell.
U.S. Pat. No. 4,690,508 issued to Jacob and entitled "Liquid Crystal Closed-Loop Controlled Mirror Systems", is directed to a rear view mirror system of an automotive vehicle, which reflects light at variable intensities. The rear view mirror system includes a mirrored reflecting surface, a liquid crystal unit, two light sensors, a pair of adjustment devices and an electronic circuit, all located within a housing. The mirrored reflecting surface is located behind the liquid crystal unit and tilted with respect to the liquid crystal unit. One of the light sensors detects ambient light and the other light sensor detects the light which reaches the mirrored reflecting surface after passing through the liquid crystal unit. The mirrored reflecting surface is tilted with respect to the liquid crystal unit, thereby preventing first surface reflections from the liquid crystal unit to from reaching the driver, where the mirrored reflecting surface was substantially parallel with the liquid crystal unit.
The electronic circuit changes the opaqueness of the liquid crystal unit in a closed control loop, according to signals received from the two light sensors, thereby changing the intensity of the light which is reflected by the mirrored reflecting surface. When the intensity of the incident light to the liquid crystal unit increases, the electronic circuit increases the opaqueness of the liquid crystal unit. Conversely, when the intensity of the incident light to the liquid crystal unit decreases, the electronic circuit decreases the opaqueness of the liquid crystal unit. When the ambient light changes from brighter to darker, the electronic circuit increases the opaqueness of the liquid crystal unit. Conversely, when the ambient light changes from darker to brighter, the electronic circuit decreases the opaqueness of the liquid crystal unit. The driver can change the opaqueness of the liquid crystal unit manually, by the pair of adjustment devices.
International Publication No. WO 02/06888 A1 published on 24 Jan. 2002 and entitled "Bistable Liquid Crystal Devices", is directed to methods to change the direction of alignment of the molecules of a liquid crystal device. The liquid crystal device includes a layer of liquid crystal material containing a dichroic additive, sandwiched between a first substrate and a second substrate. The surface of the first substrate is treated in order to introduce surface profiles having different azimuthal directions and thus provide azimuthal bistable surface alignment. The profiles can be 90 degrees apart. The surface of the second substrate is rubbed in order to provide planar alignment.
Linearly polarized light which strikes the first surface applies a torque to the molecules of the liquid crystal material. When an electric field is applied across the liquid crystal device, the molecules produce a homeotropic orientation. When the electric field is removed, the alignment of the first substrate relaxes to the direction of polarization of the linearly polarized light. This alignment is transferred to the second substrate, such that all molecules of the liquid crystal material are aligned in the direction of polarization of the linearly polarized light, even after removal of the linearly polarized light. When a dye or a light absorptive material is incorporated with the liquid crystal material, the linearly polarized light induces local heating, which assists the alignment of the molecules with the direction of polarization of the linearly polarized light.
A report published by Dozov et al., and entitled "Fast Bistable Nematic Display From Coupled Surface Anchoring Breaking", is directed to a bistable nematic liquid crystal, whose structure can be switched between a uniform (untwisted) stable state and a twisted stable state. This report is published in collaboration with SFIM-ODS SPIE Vol. 3011115 027-786X/97 p 61-69.
The bistable nematic liquid crystal in the uniform state, operates as a half-wave plate, so that if the bistable nematic liquid crystal is located between crossed polarizers, maximum light is transmitted. In the twisted state, the bistable nematic liquid crystal operates as an isotropic chiral optical system which introduces a relatively small rotation of the polarization (i.e., 10-30 degrees). Thus, with crossed polarizers, the bistable nematic liquid crystal in the twisted state is relatively dark.
In the uniform state, the molecules of the bistable nematic liquid crystal are uniformly parallel with the two plates of the bistable nematic liquid crystal. In the twisted state, only the layer of the molecules adjacent to the two plates are parallel to each plate and the other molecules are twisted between the two layers, thereby providing a twist of 180 degrees. The bistable nematic liquid crystal can be switched to the twisted state while passing through a homeotropic intermediate state, by applying a rapidly decreasing electric field. The bistable nematic liquid crystal can be switched to the uniform state while passing through the homeotropic intermediate state, by applying a slowly decreasing or a stepwise electric field.

System and method for varying the reflectance or transmittance of light


A baby blanket includes a generally rectangular base cloth panel with a front face and an opposite rear face and a front cloth panel defining five edges. The front cloth panel is attached to the base cloth panel along four of the five edges so as to define a pocket between the front and base cloth panels and to define an opening into the pocket between the fifth edge of the front cloth panel and the base cloth panel, the pocket configured to receive the baby therein such that the front cloth panel covers substantially the entire torso of the baby. A plurality of tie members are attached to the front cloth panel proximate the fifth edge of the front cloth panel, the plurality of tie members configured to releasably couple to corresponding tie members attached to the base cloth panel so as to maintain the opening in a closed position and inhibit entry into the pocket when the blanket is not in use.

1. Field of the Invention
The present invention relates to blankets, and more particularly to a baby receiving blanket with a pocket for receiving the baby therein.
2. Description of the Related Art
Conventional baby blankets consist of a single layer of material (e.g., cotton, fleece or quilted material). In use, the blanket is spread into an open configuration and the baby is placed on the blanket, after which the blanket is wrapped around the baby. However, wrapping the baby in this manner with a conventional blanket requires time and effort, and is sometimes awkward. Additionally, wrapping a baby with such a blanket may not completely enclose the baby and leave gaps through which air can flow and prevent the baby from being effectively protected against, for example, wind or cold weather. Further, many conventional approaches to wrapping a baby do not adequately secure the baby in the wrap.

Baby receiving blanket having pocket for receiving the baby


Compounds of the following formula are provided:

1. Field of the Invention
This invention concerns 2,6,9-trisubstituted purines that have been discovered to be selective inhibitors of cell cycle kinases and, as such, the compounds are inhibitors of cell proliferation. The 2,6,9-trisubstituted purines are useful in for example in—treating autoimmune diseases, e.g. rheumatoid arthritis, lupus, type I diabetes, multiple sclerosis, etc., in treating cancer, cardiovascular disease, such as restenosis, host vs graft disease, gout, polycystic kidney disease and other proliferative diseases whose pathogenesis involves abnormal cell proliferation.
This invention also concerns 2,6,9-trisubstituted purines that have been discovered to be potent and specific inhibitors of IκB-α kinase that prevents signal induced NF-κB activation and cytokine synthesis in vitro and in vivo. Such inhibitors are expected to inhibit the synthesis of cytokines and adhesion proteins whose synthesis is transcriptionally regulated by NF-κB. Proinflammatory cytokines such as 1L-1, 1L-6, TNF and adhesion proteins (e.g. ICAM, VCAM and selections) belong to this class of molecules and have been implicated in the pathogenesis of inflammatory diseases. Thus, a potent inhibitor of IκB-α kinase is useful in the clinical management of diseases where NF-κB activation is required for disease induction.
2. Description of the Art
In the past few years, advances in molecular and cellular biology have contributed to our understanding of the mechanisms of cell proliferation and of specific events that occur during progression of cells through mitosis, e.g., "Progress in Cell Cycle Research" Vol 1, Eds. L. Meijer, S. Guidet and H. Y. L. Tung; Plenum Press, New York, 1995. These studies have shown that progression through the cell cycle is controlled by a family of serine/threonine kinases called cyclin dependent kinases. These enzymes contain (a) a catalytic protein called cyclin dependent kinase (CDK) that uses ATP as a substrate and (b) a regulatory protein called cyclin. Different cyclin-CDK combinations control events such as growth, DNA replication, and cell division. One key member of the CDK family of enzymes is CDK2. CDK2 activity has been shown to be essential for mammalian cell cycle progression at the G1/S boundary. Microinjection of antibodies directed against CDK2 blocks the progression of human diploid fibroblasts into the S phase of the cell cycle. Expression of a CDK2 dominant negative mutant in human osteosarcoma cells has a similar effect. Together, these studies indicate that inhibition of cellular CDK2 activity will prevent progression of cells through the mitotic cycle and induce growth arrest prior to the S phase. Consistent with this view, in vitro studies with olomoucine (2-(hydroxyethylamino)-6-benzylamino-9-methylpurine), have shown that it is a specific inhibitor of CDK2 with an IC50 of approximately 2.1 μg/ml J. Vesely, et al.; Eur. J. Biochem 224, 771–786 (1994), L. Meijer "Chemical Inhibitors of Cyclin-Dependent Kinases" pp 351–356 in "Progress in Cell Cycle Research Vol 1, Eds. L. Meijer, S. Guidet and H. Y. L. Tung; Plenum Press, New York, 1995. In vivo studies using mammalian cells in culture have shown that olomoucine inhibits cell proliferation at an approximate concentration of 50 μg/ml.
In this invention, we have developed several compounds whose biological activity is considerably more potent than olomoucine. In vivo studies using mammalian cells indicate that some of the disclosed compounds inhibit cell proliferation at concentrations that are significantly lower than olomoucine.
Recently an IκB-α kinase activity has been described in the cytoplasm of stimulated human umbilical vein endothelial cells (Bennett et al (1996) J. Biol. Chem 271, 19680–19688). Some of the compounds of this invention have been identified as potent and specific inhibitors of IκB-α kinase that prevents signal induced NF-κB activation and cytokine synthesis in vitro and in vivo. The activation of the heterodimeric transcription factor NF-κB is a complex process. In unstimulated cells, the NF-κB (p50/p65) heterodimer is located in the cytosol where it is complexed with an inhibitory subunit IκB-α, IκB-α, binds to NF-κB thus masking its nuclear localization signal and preventing translocation to the nucleus. Upon stimulation of cells with a variety of signals (e.g. lipopolysaccharide) IκB-α is rapidly phosphorylated, uniquitinated and degraded by the proteasome. Degradation of IκB-α, allows the translocation of NF-κB to the nucleus where it activates transcription of a number of inflammatory response genes.
These observations suggest that IκB-α kinase is an attractive target for the identification of inhibitors that may be useful in the treatment of inflammatory diseases where NF-κB activation is required for disease induction.

This patent is subject to a terminal disclaimer.

Purine inhibitors of cyclin dependent kinase 2 and IκB-α

Abstract: In the Formula (I), R1 is —X—R1′; in which R1′ is optionally substituted lower alkyl, optionally substituted aryl, optionally substituted heteroaryl, or optionally substituted heterocyclyl, and X is —NH—. R2 is lower alkyl optionally substituted with one, two or three groups chosen from hydroxy, lower alkoxy, and halogen. And R3 is —NR4R5; in which R4 is hydrogen and R5 is lower alkyl substituted with amino; or (ii) R4 and R5 are both lower alkyl optionally substituted with one, two or three groups chosen from hydroxy and amino. It is to be understood that R1′ is not cyclohexylmethyl, phenyl, substituted phenyl, benzyl, phenylethyl, or m-hydroxybenzyl. The compounds inhibit CDK-2 activity and are useful for treating disorders characterized by undesirable cell proliferation.


A method and system for engine monitoring comprises a monitoring device and a remote device that are in communication. The monitoring device is incorporated in or directly attached to the internal combustion engine and functions to sense a characteristic of the internal combustion engine. The monitoring device is configured to transmit data representative of the sensed characteristic to a remote application running on a remote device. The remote device is configure to produce engine monitoring data from the transmitted data using engine characterising data stored on the remote device.

Physical objects and/or devices are increasingly provided with the capability to be networked together. Often referred to as the "Internet of Things", the ability for objects and/or devices to be uniquely identified and integrated into a communication network allows for additional functionality to be provided. Typically, such networked devices/objects are referred to as "smart" devices/objects.
For example, everyday objects/devices may include a module which monitors the performance/operation of the device and a module which communicates information regarding the performance/operation of the device over a network (i.e. the internet) to a remote device/object. Alternatively, a network connection between device/objects may be used to remotely send instructions and/or control signals to an interconnected device/object.
Typically, a smart device/object communicates with a remote device/object over a network. For example, a remote device to which a "smart" devices/object may connect to may be a server, a smart phone app or another "smart" device. Further, the network connection between the devices may be provided by, for example, an internet connection, a wireless internet connection (WiFi), a Bluetooth connection, a mobile internet connection or a combination of the above.
Often, incorporating "smart" functionality into devices/objects requires special design considerations. The module for performing the monitoring and communication may require a power source and/or a means of communicating over a network. Accordingly, devices/objects are often specially designed to incorporate smart features. As such, incorporating smart features into existing devices is often challenging.
In particular, "smart" functionality is increasingly being incorporated into machines incorporating engines in order to provide improved monitoring of such machines.
One known type of device for monitoring such a machine is an engine data logger. Engine data loggers may be used to monitor various engine parameters over time, such as engine speed. Monitoring engine speed over time may help with analysis of various aspects of the engine and its use, for example how a machine operator is typically using the machine's engine, what likely engine wear may be, etc.
Existing engine data loggers tend to be large and costly, either requiring an interface to a Control Area Network (CAN) bus in order to obtain a reading of the current engine speed from an Engine Control Unit (ECU), or requiring additional measurement equipment (such as mechanical, magnetic or laser tachometers, or fuel measurement equipment). Establishing an interface to the CAN bus may be difficult and time consuming, and providing additional measurement equipment may be costly and inconvenient.
Some existing engine data loggers may be configured to establish an internet connection with a server, where engine speed measurements may be stored over time and/or analysed. Establishing such connections can be costly, inconvenient and potentially unreliable, for example when the machine is located at the geographical limits of an internet network (for example, at the geographical limits of a Radio Access Network (RAN) cell, or at the geographical limits of a WiFi network area, etc.).
Furthermore, it may also be desirable to obtain data in relation to a legacy machine that does not have appropriate inbuilt sensing and/or communications functionality. Accordingly, it may be desirable to attach such sensing functionality to an engine retrospectively. There may be a desire to achieve the functionality with maximum ease and minimum downtime.

System for remote monitoring engine parameters


A method and apparatus for growing a crystalline or poly-crystalline body from a melt is described, wherein the melt is retained by capillary attachment to edge features of a mesa crucible. The boundary profile of the resulting melt surface results in an effect which induces a ribbon grown from the surface of the melt to grow as a flat body. Further, the size of the melt pool is substantially reduced by bringing these edges close to the ribbon, thereby reducing the materials cost and electric power cost associated with the process.

Silicon sheet material or ribbon is particularly important in making low cost solar cells. Continuous growth of silicon ribbon obviates the need for slicing of bulk produced silicon. Methods for doing this are described in U.S. Pat. Nos. 4,594,229; 4,627,887; 4,661,200; 4,689,109; 6,090,199; 6,200,383; and 6,217,649, the disclosures of which are herein incorporated by reference in their entireties. In these patents, continuous silicon ribbon growth is carried out by introducing two high temperature material strings up through a crucible that includes a shallow layer of molten silicon. The strings serve to stabilize the edges of the growing ribbon and the molten silicon freezes into a solid ribbon just above the molten layer. The molten layer that forms between the strings and the growing ribbon is defined by the meniscus of the molten silicon. U.S. Pat. Nos. 6,090,199 and 6,217,649 describe a method and apparatus for continuous replenishment of the feedstock material in a continuous silicon ribbon.
In order to produce lower cost solar cells and hence expand large-scale electrical applications of solar electricity, it is important to have lower cost and higher quality substrate materials for making the solar cell. The current invention provides new and improved methods and apparatus for growing silicon ribbons.


A heat sink conduit, for use in cooling electronic devices, made of an elongate strip of thermally conductive material that is repeatedly folded onto itself in an accordion, sinusoidal or serpentine like manner. The elongate strip is compressed between a heat producing component and a heat sink. This compression causes each of the two end segments of the elongate strip to be in positive contact with either the heat producing component or the heat sink. This positive contact allows the heat to be conducted away from the heat producing component to the heat sink and the large surface area of the conduit provides for the transfer of heat through convection and radiation, thereby cooling the heat producing component and the electronic device.

Electronic computer components produce waste heat which, if not properly dissipated, can become excessive and cause damage to the components. Therefore, controlling and dissipating the heat is important to prevent damage to the computer. As computer technology advances, removal of waste heat becomes increasingly important. Many computer components of today are smaller, faster and more powerful and produce more heat per unit volume than past components. It is known to use heat sinks to dissipate heat generated by the electronic components to prevent over heating. Usually, the heat producing component is attached to a heat sink with a type of radial arm. In order to remove heat efficiently, there should be a well defined thermally conductive path between the heat producing component and the heat sink.
There are many techniques used to remove thermal energy from electronic devices. One such technique is described in U.S. Pat. No. 5,207,902 to Bellar et al. This patent discloses the use of a radial arm between two thermally conductive membranes. One membrane is attached to an integrated circuit and the other membrane to the heat sink. This allows the heat to transfer from the integrated circuit through the radial arm to the heat sink.
Another technique is described in U.S. Pat. No. 5,397,919 to Tata et al. which describes a heat sink assembly for use with a microprocessor chip. The assembly has a finned heat sink with a threaded base that screws into a threaded bore of an adaptor, into which the microprocessor chip is placed. Thermal contact is achieved by screwing down the heat sink until it contacts the microprocessor chip.
This contact allows the thermal energy to be transferred from the microprocessor to the heat sink.
Yet another technique is described in U.S. Pat. No. 5,353,863 to Yu. A device for cooling a Pentium chip is disclosed having a flanged heat sink that clamps to the chip with clamping plates. The plates conduct heat from the Pentium chip toward the top of the heat sink and a fan is mounted to the heat sink to dissipate the heat out of the computer chassis.
In U.S. Pat. No. 5,402,313 to Casperson et al., another technique is disclosed that uses a canted coil spring to apply direct pressure to the integrated circuit chips. The assembly consists of a heat sink housing, a thermally conductive film that the integrated circuit chips are pressed against and a housing or abutment to counteract the force of the spring. The spring force is applied to the chip to produce contact between the integrated circuit chip and the heat sink to allow for thermal dissipation.
There are many other known devices and techniques to dissipate heat from electronic components. There are limits to the effectiveness of the known devices. Many of these devices are expensive or complicated to produce. Many cannot adequately dissipate heat from the new generation of microprocessors. Since the components are smaller, there is now less space available for a heat sink in today's electronic equipment. The industry needs a heat sink conduit that occupies less space. The problem is magnified as computers and microprocessors get smaller, faster and more powerful due to higher circuit density producing even more heat in the smaller confined space. A heat sink conduit is needed that can be used in small spaces with smaller integrated circuit chips.
There is also a need for a heat sink conduit of a simpler design. Many of the known devices are mechanically complex, not easy to install, and may be difficult to remove when the device or component needs repair. A heat sink conduit is needed that has fewer parts, is easier to install, and easier to remove when service of the device or component is required. Also, a cheaper heat sink conduit is needed. Many of the known devices are expensive to manufacture and install.
There is also a need for a heat sink conduit that conducts heat efficiently from the heat generating component to the heat sink. As electronic components get smaller and more powerful, they generate more heat in a smaller, more confined space. One example is the Pentium processor, which generates more heat in a smaller area than its predecessors. Many previous devices are not adequate to dissipate heat from the new processors. Therefore, a heat sink conduit is needed that is more efficient at dissipating waste heat to the heat sink.


A computer-implemented method for analyzing calendar entries may include receiving, at a computing device, at least one calendar entry associated with a calendar application, the calendar entry comprising data defining a meeting type; tracking a user's activity in the meeting type; detecting at least one related calendar entry related with the received calendar entry, wherein the detected related calendar entry comprises a meeting type related to the meeting type of the received calendar entry; and supplementing the related calendar entry with at least one indicator describing the user's activity in the meeting type based on the tracked user activity.

During business operations, organizations may choose to conduct business meetings that may focus on a number of topics that improve performance by some workers or other persons, set goals, and/or coordinate with other workers or persons all in order to build the organization. These meetings may, however, take time out of the person's day and, in some cases, may prevent any given person from actually working. Indeed, these meetings may take up so much of a person's day that the people working with and around them (i.e., team leads/managers and peers) may not realize how much time these persons actually spend active in meetings. Additionally, these team leaders/managers and/or peers may not understand what amount of time these persons actually have available in a work day. Conversely these persons also have a difficult time understanding and sharing their true availability beyond what is displayed on their calendars. Therefore, when looking at calendars, peers don't have a true indication of how engaged that person historically is in any given meeting. Answers to the questions "are they really unavailable?," "do they usually attend that meeting or merely parts of it?," "should they be in the meeting?," "are they multi-tasking while the meeting is going on?" are not knowable to their peers.

INTERNATIONAL BUSINESS MACHINES CORPORATION


Methods, circuits, and apparatus for calibrating an in-phase and quadrature (IQ) imbalance of a communication signal including an in-phase component and a quadrature component in a communication apparatus, the method including determining whether to calibrate the IQ imbalance of the communication signal in the communication apparatus; selecting, in response to a determination to calibrate the IQ imbalance of the communication signal, at least one of an amplitude calibration or a phase calibration; controlling, in accordance with the selected amplitude calibration or phase calibration, at least one of an in-phase delay circuit or a quadrature delay circuit to adjust a pulse of at least one of a first LO signal or a second LO signal to thereby generate at least one pulse-adjusted LO signal; and multiplying the at least one pulse-adjusted LO signal with the communication signal to thereby calibrate the IQ imbalance.

In a wireless communication device, a signal to be transmitted needs to be mixed with a local oscillator (LO) signal to relocate the signal to a radio frequency (RF) for transmission. On the other hand, a received RF signal needs to be mixed with an LO signal to relocate the received RF signal to an intermediate frequency (IF) or baseband frequency for further processing of the signal during reception. The wireless communication device thus contains one or more mixers that mix the signal to be transmitted and the received RF signal by multiplying the signals with the LO signals. When the wireless communication device transmits and receives complex signals, it mixes in-phase (I) components and quadrature (Q) components of the complex signals with two LO signals that have equal amplitude and are phase shifted from each other by 90 degrees.
FIG. 1(A) illustrates exemplary ideal in-phase and quadrature components of the mixed complex signal. As shown in FIG. 1(A), an I component and a Q component of the complex signal have equal amplitude, and the I component is 90 degrees phase shifted from the Q component. In other words, the I and Q components are orthogonal to each other. However, due to channel property and/or hardware impairment, the I and Q components may not be balanced. To illustrate, FIG. 1(A) shows balanced I and Q components in a transmitter or a receiver of the wireless communication device. on the other hand, FIG. 1(B) illustrates imbalanced I and Q components of the mixed complex signal. As shown in FIG. 1(B), the I and Q components are amplitude imbalanced, i.e., |I|≠|Q|, where |I| and |Q| are the amplitudes of the I and Q components. The I and Q components are also phase imbalanced, i.e., φ≠90°, where φ is phase shift between the I and Q components. Such IQ imbalance may cause transmission or reception performance degradation in the wireless communication device. Thus, it would be desirable to have a method, circuit, or apparatus for IQ imbalance calibration in the wireless communication device.
Embodiments of the disclosure provide methods, circuits, and apparatus for calibrating an IQ imbalance, which improve amplitude and/or phase balance between I and Q components of complex signals in a wireless communication device.

Methods, circuits, and apparatus for calibrating an in-phase and quadrature imbalance


An example valve includes: a pressure compensation spool configured to be subjected to a first fluid force of fluid received at an inlet port of the valve; a sleeve having a cavity and at least one throttling cross-hole; a throttling spool disposed in the cavity of the sleeve and configured to be axially movable therein, wherein the throttling spool blocks the at least one throttling cross-hole when the valve is unactuated; and a pressure compensation chamber, wherein when the valve is actuated, the throttling spool moves in the proximal direction to form a throttling flow area between a distal end face of the throttling spool and an edge of the at least one throttling cross-hole, allowing fluid flow from the inlet port to the pressure compensation chamber, thereby causing a second fluid force to be applied on the pressure compensation spool, allowing flow to an outlet port of the valve.

A hydraulic valve directs the flow of a liquid medium, usually oil, through a hydraulic system. The direction of the oil flow is determined by the position of a spool or a poppet. The size of the valve may be determined by the maximum flow of the hydraulic system through the valve and the maximum system pressure.
An example valve may have a movable element inside a housing or sleeve. For instance, the valve may include a spool that is movable by an actuation mechanism (e.g., electric, hydraulic, pneumatic, or manual). Once the valve is actuated, the spool moves to allow fluid flow from a first port to a second port.
In example valves, fluid flow can cause flow forces to oppose the actuation force applied to the spool. As a consequence, the valve might not operate as expected or a large actuation force (e.g., a larger solenoid coil that can achieve a higher solenoid force) is used to make up for such opposing flow forces.
Therefore, it may be desirable to have a valve that reduces the flow forces so as to reduce the required actuation force, thereby reducing the cost of the valve. It is with respect to these and other considerations that the disclosure made herein is presented.

Proporational flow control valve with an integrated pressure compensator and features for flow force reduction


In a non-volatile memory device, the level of a verifying voltage supplied to a word line is adjusted in accordance with occurrence of a source line bouncing phenomenon. The non-volatile memory device includes a bouncing sensing circuit configured to compare a source line current passing through a common source line with a reference current, and output a bouncing sensing signal in accordance with the comparing result, and a word line voltage controller configured to provide a verifying voltage increased by a certain level to a word line in accordance with level of the bouncing sensing signal.

The present invention relates to a non-volatile memory device and more particularly to a method for adjusting a level of a verifying voltage supplied to a word line to reduce a source line bouncing phenomenon.
Recently, the demand has increased for a non-volatile memory device which electrically programs and erases data, and does not require a refresh function for periodically rewriting data.
The non-volatile memory device generally includes a memory cell array having matrix-typed cells for storing data, and a page buffer for programming data to a specific memory cell or reading data from a certain cell.
The page buffer has a pair of bit lines connected to a given memory cell, a register for temporarily storing data to be programmed to the memory cell or data read from a certain cell, a sensing node for sensing a voltage level of a specific bit line or voltage level of a certain register, and a bit line selecting circuit for controlling connection of the bit line and the sensing node.
In a program operation of the non-volatile memory device, if source line bouncing occurs, it may be verified that a specific cell is programmed even though the cell is not adequately programmed. As a result, when reading the cell after the program operation is finished, the cell may be read as not programmed.


An electrostatic chuck device includes: in order, an electrostatic chuck part having one principal surface serving as a placing surface on which a plate-shaped sample is placed, and having a built-in internal electrode for electrostatic attraction; a heating member bonded to a surface on the side opposite to the placing surface of the electrostatic chuck part in a pattern having gaps; a sheet material; and a base part having a function of cooling the electrostatic chuck part, in which a silicone resin sheet having a layer thickness of 10 μm or more and less than 200 μm and a Shore hardness (A) in a range of 10 to 70 is provided between the electrostatic chuck part and the heating member.

In a semiconductor manufacturing process, in the processing of a wafer, an electrostatic chuck device is used as a device for easily mounting and fixing the wafer on and to a sample stage and maintaining the wafer at a desired temperature.
Finer processing of the wafer is progressing according to higher integration and higher performance of a semiconductor element, and a plasma etching technique which is high in production efficiency and enables fine processing of a large area is frequently used. If the wafer fixed to the electrostatic chuck device is irradiated with plasma, the surface temperature of the wafer rises. Therefore, in order to suppress a rise in the surface temperature, the wafer is cooled from the lower side by circulating a cooling medium such as water in a base part of the electrostatic chuck device. However, at this time, due to unevenness of heat input to the wafer by plasma in the surface of the wafer, a temperature distribution occurs in the surface of the wafer. For example, a temperature tends to become high at a central part of the wafer and become low at an edge portion of the wafer.
For example, in an electrostatic chuck device in which an in-plane temperature distribution of a wafer is adjusted using gas such as helium, or an electrostatic chuck device in which a contact area between a wafer or the like and an attraction surface of an electrostatic chuck is adjusted, it is difficult to perform local temperature control.
Further, in an electrostatic chuck device with a heater function according to the related art, there is a case where cracks are generated in an electrostatic chuck part, a base part, or a heater itself due to rapid rise and fall in temperature of the heater, and thus there is a problem in which durability as an electrostatic chuck device is insufficient.
In order to solve such a problem, there is disclosed, for example, an electrostatic chuck device in which in a case of being applied to a treatment apparatus such as a plasma etching apparatus, it is possible to perform local temperature control of a plate-shaped sample such as a silicon wafer associated with plasma application by generating a local temperature distribution in the surface of the plate-shaped sample such as a silicon wafer (refer to, for example, Patent Literature No. 1).

Electrostatic chuck device including a heating member


The present invention relates to relates to methods of making concrete from cement and, in particular, methods of making usable standard concrete from aged or otherwise substandard cement.

The following includes information that may be useful in understanding the present disclosure. It is not an admission that any of the information provided herein is prior art nor material to the presently described or claimed inventions, nor that any publication or document that is specifically or implicitly referenced is prior art.
It is generally known in the industry that exposure of cement to the surrounding atmosphere causes absorption of moisture from air and an irreversible chemical interaction of the cement with water—hydration. As a result, the cement loses its activity over time as the duration of exposure to air increases. Portland cement is designed to react chemically with water and any exposure to the surrounding moisture will cause it to set and harden. The universal recognition of this inevitable deterioration of cement during transportation and storage explains its limited guaranteed shelf life being generally limited to six months, and in some cases cement only remains useful for a period of three months or less from delivery to the end user. The negative impacts of this prehydration on the cement activity and concrete strength has been long recognized.
Accordingly, there have been attempts to address this issue through chemical modification of cement. A historical example is found in U.S. Pat. No. 2,996,394 (Stoll) which discloses a hydrophobic, non-caking cement product adapted for protracted storage in high humidity areas, consisting of Portland cement, 0.1 to 0.4 percent of oleic acid, and 0.04 to 0.20 percent of tri-n-butyl phosphate (a detraining agent).
Another example is found in U.S. Pat. No. 10,590,040 (Ozersky et al.) which discloses a macro-cement and associated methods useful for preparing pastes, mortars, concretes and other cement-based materials having high workability, high density, and high strength. A method of producing a macro-cement is disclosed which includes cement, supplemental cementitious materials (SCM's), including siliceous submicron-sized particles and nano-sized particles, and polymers in the form of liquid or dry chemical admixtures for concrete. The cement mixture may be used for making ultra-high performance concrete (UHPC). The macro-cement can be produced in the form of granules, pellets, briquettes or tablets by mechanical activation during the process of coating and/or loading of the cementitious materials in order to extend the shelf life.
The above patent describes "macro-cement" as referring to both the dry cement produced from the combination of the above ingredients and the mixture of the ingredients themselves. Macro-cement can come in various forms, such as granulated, pelletized, briquetted, tabletted engineered dust-free macro-cement forms with extended shelf life and high workability useful for preparing pastes, mortars, concretes and other cement-based materials with high density and strength, increased early and final strengths, and accelerated reaction rate in cementitious mixtures.
Yet another example is found in International Patent Application Publication No. WO2020/073119A1 (Ozersky et al.) which discloses a process for producing a self-protecting cement by combining a cement precursor and a wax, where the wax comprises alkyl ketene dimer wax and/or alkenyl ketene dimer wax; and grinding the cement precursor and the wax to yield cement grains coated with wax in order to extend the shelf life of the cement.
The above publication describes "self-protecting cement" as referring to a cement which is protected to a significant degree from deterioration from contact with atmospheric moisture and from accidental short-term contact with water prior to preparing cement compositions, or, in other words, is substantially hydrophobic.
However, shelf life remains an issue for cement. Furthermore, there still remains the problem of attempting to use or otherwise recover cement that has been compromised in order to form useful concrete.
Accordingly, there remains a need for improvements in the art.


A valve spring top collar is formed by a unitary body having a circular top face and a bottom surface, with a first circular shoulder extending downwardly from the bottom surface of the body and a second inwardly spaced circular shoulder. The shoulders are inserted into the valve springs so that the springs cannot slip off the collar in a radial direction. A central aperture extends through the central core of the body, through which a valve stem is inserted. A plurality of peripheral apertures extend through the body about the central aperture, thereby decreasing the total weight of the collar and allowing flow of lubricant to the springs.

In internal combustion engines, the intake and exhaust valves are actuated by a cam or rocker pushing against the end of the valve stem, which then slides through the valve guide. The valve head at the end of the valve stem then clears its seat and opens the passage between the intake or exhaust passageway and the combustion chamber, allowing gases to enter or exit the chamber. The valve is forced to follow the motion of the cam or rocker by a valve spring, which may actually consist of several springs of varying diameter, with the inner spring(s) lying within the coils of another spring. The valve spring sits in a state of compression between the valve spring seat, which is mounted on the cylinder head and is therefore stationary, and the valve spring top collar, which is affixed to the end of the moving valve stem. The spring force is thereby transmitted to the valve stem, which is thus forced against the cam or rocker as the cam or rocker rises, causing the valve to close. A common conventional valve spring top collar resembles a solid disk with a central opening to admit the valve stem and a raised shoulder (or shoulders) on its underside to which the valve spring (or springs) is engaged.
A longstanding goal of engine design is to produce greater engine power while simultaneously achieving better fuel economy. Engine components of lighter weight further this goal because lower engine component weight decreases the amount of work necessary for operation, thereby increasing engine efficiency.


A filter media for an air filter includes at least two layers of filter material with the materials being different. The layers are joined together by a stiffening grid fabricated from a metal or plastic. Glue such as hot-melt glue is disposed on both sides of the grid to attach the sides of the grid to the respective layers. Depending upon the application, the filter media may be pleated.

Air filters such as those used in HVAC systems are fabricated with many different types of filter media. Depending upon the type of substance sought to be filtered or removed from air (e.g. particles, carbon monoxide, smoke, formaldehyde, organics, etc.), or the useful filter life required, different medias are selected. Examples of such medias are wet or dried laid paper, synthetic microfiber media, metal mesh, wet or dried laid fiberglass, activated carbon impregnated media, tack coated polyester and synthetic media impregnated with potassium permanganate.
One of the problems which arises as a result of selecting a specific filter media for a specific filtering requirement (e.g. filtering carbon monoxide) is that filtering performance for other requirements such as particulate filtration may be sacrificed. Accordingly, it would be desirable to combine different types of filter material layers to produce a filter media which will meet more than one filtering requirement. It would also be desirable to provide an arrangement for joining the filter material layers to allow both layers to be supported with a support grid.


An improved surgical stapler which allows for the multi-directional release of staples includes a stapler body and a driver contained therein. A magazine is connected to the stapler body and includes a staple track for carrying a plurality of staples wherein each of the staples has staple legs. An anvil is associated with the staple track for providing a staple forming surface for forming a staple thereon. A feeder element which is spring biased against the staples is used for feeding each staple from the staple track to the anvil. A trigger is operatively connected to the driver and is movable from a pre-fire position to a firing position for advancing the driver against the anvil for forming the staple against the anvil. A kick-off spring is positioned beneath and substantially parallel to the staple track and the anvil. The kick-off spring has a deflectable tip which is deflected away from the anvil and engages the staple legs of the staple by downwardly camming against the staple legs when the trigger is moved from its pre-fire position to its firing position. The kick-off spring ejects the staples off of and away from the anvil by disengaging the staple legs with the deflectable tip by upwardly camming against the staple legs upon returning of the trigger from the firing position to the pre-fire position.

The present invention relates, in general, to tissue fastening devices and, in particular, to a new and useful wound closure device, such as a skin stapler, that allows for the multi-directional release of a staple from the device upon firing.
It is well established in the prior art that there are many devices that exist which utilize staples for fastening tissue. Many of these existing or known devices are directed toward closing a wound, fastening a skin incision, curing a defect in tissue or fastening a prosthetic to tissue for repairing a defect or the like.
In particular, there are a number of known prior art skin staplers that contain a multiplicity of staples and are used for closing wounds or incisions in the skin. These skin staplers are usually multi-fire instruments meaning that they contain and fire a plurality of staples. These instruments are designed to be disposable and used for a single patient only.
One known prior art skin stapler is disclosed in U.S. Pat. Nos. 4,391,402; 4,406,392 and 4,591,086 (Campbell et al.). Similar to many other known skin staplers, the stapler disclosed in the above-identified patents utilities an L-shaped anvil. The L-shaped anvil configuration comprises an elongated leg portion and a small leg portion that is orthogonal or parallel to the elongated leg portion for providing a staple forming surface thereon. Accordingly, a former or driver is used to move parallel to the elongated leg portion in order to form a staple around the small leg portion of the anvil. In conjunction with the driver and anvil configuration and orientation, a leaf spring, which is a unitary part of the staple track, is utilized for retaining the staple stack away from the staple being formed, e.g. the distal-most staple, on the small leg portion of the anvil in order to prevent the staple stack from interfering with the forming of the distal-most staple.
Other known skin staplers are disclosed in U.S. Pat. No. 3,643,851 (Green et al.) and U.S. Pat. No. 4,127,227 (Green). Similar to the prior art devices described above, these skin staplers utilize a similar anvil having a substantially L-shaped configuration. Additionally, the driver for these stapling instruments is advanced parallel to the elongated leg portion of the anvil. Additionally, a spring ejector is located adjacent the anvil for engaging the formed staple at the crown of the staple in order to lift the staple off of the anvil by its crown after firing.
In addition to the skin staplers identified above, there are other known skin staplers which also utilize a spring ejector for ensuring that the formed staple is moved away from the anvil of the instrument. These devices are identified as follows: the PRECISE PGX.TM., manufactured and sold by 3M Healthcare, St. Paul, Minn.; the Davis-Geck APPOSE ULC.TM., manufactured and sold by American Cyanamid Company, Danbury, Connecticut; VISISTAT RH.TM., manufactured and sold by Edward Weck and Company, Inc., Research Triangle Park, N.C.; and the Auto Suture (Cricket.TM., Royal.TM., Signet.TM., Concorde.TM., Elite.TM. and Multi-fire Premium.TM.) skin stapler products, manufactured and sold by United States Surgical Corporation, Norwalk, Conn. All of these skin stapler products are available in the market and utilize a similar driver and anvil configuration such as disclosed above. These devices all utilize a driver that moves substantially parallel to the elongated leg portion of the anvil in order to form a staple across the surface of the small leg portion of the anvil. Furthermore, in all of these skin stapler devices, the staple is moved away from the anvil of the instrument through the use of a spring ejector which engages the staple at the far corners of the staple crown, i.e. at the juncture of the upper most portion of the staple leg and the corner of the staple crown. Accordingly, the staple is dislodged from the surface of the anvil by using the spring ejector to force the staple off of the anvil by its crown.
As noted above, all of the known skin stapler devices utilize similar staple forming and staple release features, namely a spring ejector which releases the staple from the anvil at the crown of the staple. Accordingly, most of these instruments contain a similar number of parts. Thus, most of these known devices are manufactured at around a similar cost with respect to the number of parts utilized in these instruments.
Since skin staplers are generally a disposable, single patient use only device which are intended to be discarded after use in surgery, it is essential that these instruments be provided at the lowest cost possible, i.e. utilize an efficient configuration with minimal parts, without sacrificing quality, safety and functionality. Presently, there is no known skin stapler that provides a multi-directional release mechanism or kick-off spring for releasing staples from the instrument after firing without having to dislodge the staple from the anvil at the crown of the staple or at the juncture of the uppermost portion of the staple leg and the corner of the staple crown. Additionally, there is no known skin stapler that provides a low featured, cost effective alternative to the skin stapler products identified above.

Skin stapler with multi-directional release mechanism


A process for preparing a polyacrylamide gel plate for electrophoresis with any desired concentrations, which comprises mixing a high concentration acrylamide monomer solution, a low concentration peroxide solution, and a low concentration reducing solution at an arbitrary ratio, and introducing the mixture into a gel supporter. The process enables preparation of a large quantity of high quality polyacrylamide gel plates for electrophoresis which is useful for analysis of high molecular weight in vivo components typified by proteins with a good reproducibility. It also contributes to the production of various gels having a plurality of gel concentrations or having a specified concentration gradient, and serves for improving the productivity of multi-products manufacturing of such gel plates.

1. Field of the Invention
The present invention relates to a process for preparing a polyacrylamide gel plate for use in electrophoresis, and, more particularly, to a process for preparing a large quantity of polyacrylamide gel plates which are especially suitable for electrophoresis analysis of in vivo components with a high molecular weight, such as proteins and the like.
2. Description of the Background Art
Polyacrylamide gels have widely been used for electrophoresis analysis of in vivo components with a high molecular weight, e.g., protein, nucleic acid, and the like. Usually, these polyacrylamide gels are prepared by cross-linking polymerization of a monomer and a cross-linking agent; i.e., by adding a polymerization initiator to a 2-40% by weight aqueous solution comprising a monomer such as acrylamides and a divalent or polyvalent cross-linking agent such as N,N'-methylenebisacrylamide (such a solution is hereinafter sometimes referred to as an "acrylamide monomer solution").
As an initiation method of polymerization, either a combination of a peroxide and a reducing agent, or a combination of a peroxide, a reducing agent, a photosensitation agent and exciting ray, while the reducing agent is not necessarily used, may be used. For the latter photopolymerization method, although some methods are proposed, in which the polymerization does not take place before the light irradiation, even after a polymerization initiator added (e.g., Japanese Patent Laid-open (kokai) No. 91849/1987), the photopolymerization method basically involves many technical problems for obtaining stable gel products with a good reproducibility. The problems are found in difficulties in controlling the polymerization reaction such as shading of the reaction liquid for gel formation, selection of irradiation conditions for producing gel, and occurrence of continued polymerization in the presence of light even after the completion of gel formation. For these reasons, the former chemical polymerization method, which adopts a combination of a peroxide and a reducing agent, is preferred owing to its comparatively easy handling of the reaction liquid and capability of controlling the reaction to some extent by adjusting the amount of the catalyst used.
In the chemical polymerization method, however, since the gel reaction takes place immediately after the addition of the polymerization initiator to the monomer solution, giving rise to a viscosity increase of the solution and to gelatinization of the mixture, it is necessary to prepare a monomer solution and a polymerization initiator solution separately and mix them just before the start of the gel forming process. This separate addition of a peroxide solution and a reducing solution to the monomer solution inevitably requires complicated steps. On the other hand, if these two solutions are mixed together beforehand, the catalyst activity will change as the time passes, making it difficult to stably obtain high quality gels.
Furthermore, since a molecular sieve effect of a polyacrylamide gel varies depending on the gel concentrations, various products with different gel concentrations are required conforming to molecular weights or the like of the components to be separated or analyzed. Conventionally, this requirement for polyacrylamide gels has been fulfilled by preparing a monomer solution having a specific gel concentration, which corresponds to the subject to be separated for analysis, then adding a polymerization initiator to the solution and introducing the mixture into or spreading it over a gel-supporter. This necessitates to prepare many gel-forming solutions with different concentrations when the subjects to be analyzed contain a number of components. In addition, preparation of a gel with a concentration gradient suitable for the analysis of a subject comprising a wide molecular weight distribution is implemented by providing two monomer solutions with different concentrations, one a low concentration and the other a high concentration, and adding a polymerization initiator to the solutions. The solutions are then introduced into or spread over a gel-supporter by using a gradient forming unit. In order to obtain a number of gels with different concentration gradients, it is necessary, in the same manner as in the preparation of a series of gels with a specified concentration, to prepare beforehand various monomer solutions with different concentrations corresponding to the required gradients, and to appropriately combine these solutions. Furthermore, in order to prepare a stable gel, the amount of the polymerization initiator must be adjusted appropriately so that not too less or not too much of it is incorporated relative to the concentration of the monomer solution to be used.
As noted above, stable supply of high quality polyacrylamide gels in large quantities has been difficult to achieve by conventional preparation methods which involve rather complicated manufacturing steps and require sophisticated skills.
An object of the present invention is, therefore, to provide an easy production process which can prepare a large quantity of various kinds of high quality and stable acqueous polyacrylamide gels, having a high resolving power and any desired concentrations or concentration gradients, with a good reproducibility, and which does not involve the problem of changes in the polymerization initiator activity before being introduced into a gel-supporter or does not require to prepare many monomer solutions or many polymerization initiator solutions of different concentrations beforehand.
In view of this situation, the present inventors have undertaken intensive studies to solve the aforementioned problems, and found that a high quality gel with a desired concentration can constantly and easily be prepared with a good reproducibility and without any changes in the catalyst activity using an optimum amount of a polymerization initiator, by simply preparing one monomer solution with a high concentration, one peroxide solution with a low concentration, and one reducing solution with a low concentration, and mixing them at an appropriate ratio prior to use. These findings have led to the completion of the present invention.

Process for preparing polyacrylamide gel plate for electrophoresis


A method for operating an anaerobic ammonium oxidation vessel in anaerobic ammonium oxidation in which ammonium and nitrite in water to be treated are simultaneously denitrified by anaerobic ammonium oxidizing bacteria, the method comprising the steps of:

1. Field of the Invention
The present invention relates to a method for operating an anaerobic ammonium oxidation vessel and anaerobic ammonium oxidation equipment, in particular, to a method for operating an anaerobic ammonium oxidation vessel and anaerobic ammonium oxidation equipment, in which ammonium and nitrite in water to be treated are simultaneously denitrified by anaerobic ammonium oxidizing bacteria.
2. Description of the Related Art
Nitrogen components contained in sewage and industrial effluent cause eutrophication in lakes and lower the level of dissolved oxygen in rivers, and thus must be removed. Examples of main nitrogen components contained in sewage and industrial effluent include ammonium nitrogen, nitrite nitrogen, nitrate nitrogen, and organic nitrogen.
Conventionally, when nitrogen in such wastewater has a low concentration, ion exchange and oxidation by chlorine or ozone are used to remove nitrogen. When the nitrogen has a medium or high concentration, biological treatment is employed and usually operated in the following conditions.
In the biological treatment, nitrification and denitrification treatment is performed by aerobic nitrification and anaerobic denitrification. In the aerobic nitrification, ammonium nitrogen and nitrite nitrogen are oxidized by ammonium oxidizing bacteria (Nitrosomonas, Nitrosococcus, Nitrosospira, Nitrosolobus, etc.) and nitrite oxidizing bacteria (Nitrobactor, Nitrospina, Nitrococcus, Nitrospina, etc.). On the other hand, in the anaerobic denitrification, denitrification is performed by heterotrophic bacteria (Pseudomonas denitrificans, etc.).
A nitrification vessel for aerobic nitrification is operated under a load of 0.2 to 0.3 kg-N/m3/day, and a denitrification vessel for anaerobic denitrification is operated under a load of 0.2 to 0.4 kg-N/m3/day. To treat nitrogen contained in a total concentration of 30 to 40 mg/L in sewage, the sewage must be retained in a nitrification vessel for 6 to 8 hours and in a denitrification vessel for 5 to 8 hours, and large-scale treatment vessels are required. Further, a nitrification vessel and a denitrification vessel are designed to be operated under the loads as described above for industrial effluent containing only inorganic substances. However, denitrification of such wastewater requires organic substances, and thus methanol is added at a concentration three to four times of that of nitrogen. For this reason, not only an initial cost but also a large running cost are required.
In this situation, recently, a method for removing nitrogen comprising anaerobic ammonium oxidation has been attracted attention (for example, Japanese Patent Application Laid Open No. 2001-37467). This anaerobic ammonium oxidation is a method comprising simultaneously denitrifying ammonium as a hydrogen donor and nitrite as a hydrogen acceptor by anaerobic ammonium oxidizing bacteria according to the following reaction formula:1.0NH4+1.32NO2+0.066HCO3+0.13H+→1.02N2+0.26NO3+0.066CH2O0.5N0.15+2.03H2O  (Formula 1)
This method has advantages in that ammonium used as a hydrogen donor can considerably reduce the amount of methanol or the like used for denitrification and reduce the amount of a sludge produced, etc. Thus, the method is considered to be an effective method for removing nitrogen in the future.
However, it is reported that anaerobic ammonium oxidizing bacteria carrying out anaerobic ammonium oxidation are typified by Planctomycete, and have a very low specific growth rate of 0.001 h−1 (Strous, M. et al., Nature, 400, 446 (1999)). Japanese Patent Application Laid Open No. 2003-24990 reports that the bacteria have a very small specific growth rate of 0.02 to 0.05 days−1, and it takes 14 to 35 culture days to double the amount of the bacterial cells.

Method for operating anaerobic ammonium oxidation vessel and anaerobic ammonium oxidation equipment

Abstract: withdrawing a part of the anaerobic ammonium oxidizing bacteria from one anaerobic ammonium oxidation vessel in which the anaerobic ammonium oxidizing bacteria have been acclimatized, and

Abstract: introducing the withdrawn anaerobic ammonium oxidizing bacteria into another anaerobic ammonium oxidation vessel in which acclimatization is to be carried out to perform start-up operation,

Abstract: wherein the anaerobic ammonium oxidizing bacteria having been acclimatized in the one anaerobic ammonium oxidation vessel are provided as microbe-immobilized materials in which the bacteria are attached to and immobilized on immobilizing materials or entrapped and immobilized in immobilizing materials.


A line exposure type image forming apparatus having a micromirror device 40 with numerous micromirrors 41 tiltable for reflecting light incident from a light source to a predetermined exposure position on a photosensitive material 2, and a sub-scan moving mechanism 8a for moving the photosensitive material relative to the exposure position. The micromirror device is disposed such that an imaginary line linking imaging positions on the photosensitive material of the micromirrors in a predetermined line is at an angle to a direction of relative movement of the photosensitive material. As a result, an exposure dot line is produced on the photosensitive material in a main scanning direction perpendicular to the direction of relative movement by a main scanning mirror set formed of micromirrors selected in a direction at an angle to a direction of the columns of the micromirror device.

1. Field of the Invention
This invention relates to a line exposure type image forming apparatus including a micromirror device having numerous micromirrors arranged in a matrix of rows and columns, each micromirror being tiltable between an exposing posture for reflecting light incident from a light source to a predetermined exposure position on a photosensitive material and a non-exposing posture for reflecting light to a location other than the photosensitive material, a sub-scan moving mechanism for moving the photosensitive material relative to the exposure position, and a mirror controller for controlling the postures of the micromirrors in response to image signals.
2. Description of the related Art
The micromirror device is also called a DMD (Digital Micromirror Device) which actuates, by action of electrostatic fields, square micromirrors of high reflectance formed on a wafer by aluminum sputtering, each with a side measuring approximately 16 (m. Several hundreds of thousands to a million of these micromirrors are squeezed into a matrix form on a silicon memory chip by CMOS semiconductor technique. Each micromirror can swing about a diagonal to tilt to two steady postures about (10 degrees relative to the horizontal. This micromirror device usually is employed, with each micromirror corresponding to one pixel, in a digital display system for projecting digital images on a screen by controlling a reflection time of light from a light source.
The micromirror device may be used to form exposure dots in selected positions on a photosensitive material, with each micromirror, in one of the two steady postures, reflecting the light from the light source to a predetermined position on the photosensitive material, and in the other posture, reflecting the light outside the region of the photosensitive material. Further, the exposure dots may be given a desired gradient by controlling irradiation time when producing the exposure dots. The micromirror device may thus be employed also in a line exposure type image forming apparatus which forms images on a photosensitive material by moving the photosensitive material relative to the irradiating positions of the micromirrors. Such image forming apparatus are known from U.S. Pat. No. 5,953,103, U.S. Pat. No. 5,933,183 and Japanese Patent Application Laying-Open Publication S10-104753, for example.
However, each of the above conventional apparatus makes use of a micromirror device designed for a digital display system. This micromirror device is not necessarily optimal for a line exposure type image forming apparatus. For example, the resolution of exposure dot images formed on a photosensitive material is dependent on the degree of mirror integration of the micromirror device. A micromirror device enabling an XGA screen resolution has 768 pixels vertically and 1024 pixels horizontally. Even where the rows, which are the longer, are used as lines to effect line exposure, and where photographic paper of 100 mm in width is used as a photosensitive material, the resolution will be about 250 dpi. Thus, demands for a higher resolution cannot be met. It is possible to double the resolution by using two identical micromirror devices, but this will entail an excessive increase in cost.
The object of this invention is to provide a line exposure type image forming apparatus employing a micromirror device, which realizes improved resolution while avoiding an increase in cost.
The above object is fulfilled, according to this invention, by a line exposure type image forming apparatus having a micromirror device disposed such that an imaginary line linking imaging positions on the photosensitive material of the micromirrors in a predetermined line is at an angle to a direction of relative movement of the photosensitive material, and an exposure dot line is produced on the photosensitive material in a main scanning direction perpendicular to the direction of relative movement by a main scanning mirror set formed of micromirrors selected in a direction at an angle to a direction of the columns of the micromirror device.
In this construction, the rectangular micromirror device is set to an oblique posture to utilize, as an exposure line, micromirrors disposed along an oblique line, instead of micromirrors in a vertical line (direction of rows) or micromirrors in a horizontal line (direction of columns). This allows use of a larger number of micromirrors as the exposure line than where micromirrors in a vertical or horizontal line are used.
To allocate a maximum number of micromirrors to the exposure line, use may be made of micromirrors disposed along a diagonal of the rectangular micromirror device, for example. As a result, numerous micromirrors arranged around the diagonal are in a pixel shifting positional relationship. An appropriate selection of micromirrors to be used in time of printing will allow for a remarkable improvement in resolution.
Where the above-mentioned oblique line acting as basis for selecting micromirrors to be used as the exposure line is inclined at 45 degrees, light beams reflected by the micromirrors conveniently have a uniformed overlapping of luminance distributions. Thus, in a preferred embodiment of this invention, where the micromirror device is rectangular, i.e. where the micromirrors are arranged in a matrix of m rows and n columns, m being smaller than n, the main scanning mirror set is formed of a plurality of subsets each having a predetermined number of micromirrors selected in a direction at an angle of 45 degrees to the direction of the columns of the micromirror device. The exposure dot lines produced by the subsets are shifted 5 from each other in the direction of relative movement of the photosensitive material (usually called the sub-scanning direction). In practice, however, a single straight exposure dot line is formed on the photosensitive material by the technique of controlling timing of driving the micromirrors in the sub-scanning direction. Since the micromirrors in each subset are arranged along a line inclined at 45 degrees, light beams reflected by the micromirrors have a uniformed overlapping of luminance distributions. The scanning mirror set is divided into a plurality of subsets as noted above. These subsets are shifted from one another only by a small amount. Thus, even where the light source has variations in luminance distribution, differences in luminance of incident light beams are negligible.
Where variations in luminance distribution of the light source are immaterial, it is proposed, as another embodiment of this invention in which the micromirror device is rectangular, that the main scanning mirror set is formed of a first subset having a predetermined number of micromirrors selected in a direction extending from one end of a diagonal of the matrix at an angle of 45 degrees relative to the columns of the micromirror device, and a second subset having a predetermined number of micromirrors selected in a direction extending from the other end of the diagonal at an angle of 45 degrees relative to the columns of the micromirror device. In this construction, the number of subsets is only two, which simplifies the timing control of the micromirrors to absorb the shift in the sub-scanning direction between the exposure dot lines produced by the subsets.
In a further preferred embodiment of this invention, at least three main scanning mirror sets are formed to produce exposure dots, each struck by light beams from different micromirrors for color exposure. This construction forms color exposure dots of high quality with color discrepancy restrained, thereby forming a high quality color image. In this case, three or more, preferably a multiple of three, main scanning mirror sets may be formed to produce exposure dots of at least one color, preferably three colors, struck by light beams from different micromirrors for color exposure. Then, the quantity of radiation to form each exposure dot may be distributed to a plurality of micromirrors. This results in an increase in the speed of movement in the sub-scanning direction, i.e. the speed of the exposing process. In a still further preferred embodiment of this invention, the main scanning mirror set, and an interpolative main scanning mirror set formed of micromirrors for producing exposure dots between exposure dots produced by the micromirrors of the main scanning mirror set, produce an exposure dot line of increased resolution. This construction effects so-called pixel shifting only by the technique of controlling timing of driving the micromirrors in the sub-scanning direction. The exposure dots thereby formed have a twofold resolution. Other features and advantages of this invention will be apparent from the following description of the embodiments to be taken with reference to the drawings.

Line exposure type image forming apparatus


The invention involves the use of a base pipe perforated only in a specific section under each screen section. Inflow comes through an outer shroud that is optional and goes through the screen material and into an annular space between the screen material and the unperforated base pipe. After traveling longitudinally in that annular space, the flow must go through a restriction that preferably comprises a porous media in a passage defined outside the still unperforated base pipe. After passing through the porous media in a particular screen section, the flow can pass through openings in the base pipe. A surrounding ring preferably protects the porous media during run in and expansion and can also optionally create additional resistance to flow to work in tandem with the porous media. Other flow restricting techniques in place of the porous media are contemplated.

Annulus flow, particularly in long horizontal runs in a formation creates an undesirable uneven flow into production tubing and encourages production of sand and along with it erosion that adversely affects downhole equipment such as screens. To combat this tendency of uneven inflow caused by annular flow around the outside of screen sections, what has been tried in the past is the addition of a flow control mechanism to individual screen sections to redirect much of the flow that used to come in closer to the uphole or heel end of the screen assembly because that would represent the path of least resistance. In essence, the solution to this problem involved the reconfiguration of the screen sections so that in each screen section the flow could go through the screen material and then in an annular space defined between the screen and the base pipe, which would be non-perforated in the screen section. After passing through that zone the flow would be put through a tortuous path before arriving at a hole in the base pipe. Each section of screen could have a form of this built in resistance so that an assembly of screens in the aggregate would equalize the flow from the formation over the length of the producing zone. To illustrate this approach, reference is made to the Equalizer™ screen sold by Baker Hughes Incorporated of Houston, Tex. and described at length in SPE Paper 78293 entitled An Investigation of the Economic Benefit of Inflow Control Devices on Horizontal Well Completions Using a Reservoir-Wellbore Coupled Model by Jody Augustine. U.S. Pat. Nos. 3,450,207; 5,435,393 and 6,112,815 are also relevant to this concept. In using these devices the annular space was traditionally gravel packed to control annular flow characteristics and limit production of undesirable sand.
More recently, the concept of expansion of pipe downhole has taken hold and screens have been expanded to reduce the size of the surrounding annulus with an eye toward eliminating the need to gravel pack. In long horizontal runs, in particular, there were concerns about the distribution of gravel and the ideal of screen expansion took hold as a way to ease those concerns by reducing the size of the annular space around a screen in open hole of a slotted liner.
However, despite the incorporation of expansion technology the issues relating to annular flow and uneven flow from the formation into the production tubing remained through screens remained. The unique construction of the known flow equalizing devices did not make an assembly that was amenable to expansion. Accordingly, the present invention is directed to an assembly that is amenable to expansion while still providing the capability to distribute flow from a formation evenly into a production string. These and other features of the present invention will be more readily appreciated by those skilled in the art by a review of the detailed description of the preferred embodiment, the drawings and the claims that appear below.


A gas turbine combustion liner having a novel and improved system for receiving a peripheral device through a floating collar is disclosed. The retaining collar assembly provides planar movement for receiving the peripheral device while preventing the floating collar from rotational movement through an anti-rotation tab on the collar and a collar cap, resulting in reduced wear to the peripheral device. The collar cap can include different configurations for reducing any vibratory effects caused by an oncoming airflow directly contacting the floating collar.

In a typical gas turbine engine used in a powerplant application, a plurality of combustors is arranged in an annular array about a centerline of the engine. The combustors receive pressurized air from the engine's compressor, add fuel to create a fuel/air mixture, and ignite the mixture to produce hot combustion gases. The hot combustion gases exit the combustors and enter a turbine, where the expanding gases are utilized to drive a turbine, which is in turn coupled through a shaft to the compressor. The engine shaft is also coupled to a shaft that drives a generator for generating electricity.
The combustors typically include at least a pressurized case and a combustion liner contained within the case. The fuel, which is supplied by a plurality of fuel nozzles, mixes with air and reacts (i.e. ignites) within the combustion liner. However, in order for the fuel/air mixture to combust, the mixture must be exposed to a flame source, which is initially generated by an igniter, such as a spark igniter. An igniter, or other peripheral device, such as a flame detector, has access to the contents of the combustion liner through one or more holes placed within a sidewall of the combustion liner. Through these holes, the igniter can extend or the flame detector can detect evidence of a flame in the combustor.
Prior art configurations of combustion liners having openings for igniters and flame detectors have included a washer-like component that can slide laterally and rotate. An example of a prior art opening in a combustion liner is shown in FIGS. 1 and 2. The prior art configuration included a boss 100 extending radially outward from the combustion liner, a floating collar 102 and a cap 104 that is secured to the boss 100 in such a way to retain the floating collar 102, but permit the floating collar 102 to slide and rotate. As compressed air passes along the outside of the combustion liner, the airstream causes the floating collar to vibrate and rotate, often contacting the peripheral device. This movement causes the floating collar 102, which is often time made from a nickel-based alloy such as Hastelloy X, to wear on the igniter or flame detector components, which are typically made of a softer material such as stainless steel. Furthermore, such contact also causes excessive wear and fracturing of the floating collars 102, requiring premature replacement of the peripheral devices.

Retaining collar for a gas turbine combustion liner


A signal receiving device and signal receiving method to pass a desired frequency component of an intermediate frequency signal by using an IF filter without increasing a chip area. The signal receiving device comprises: a mixer to mix a received frequency signal with a local oscillation frequency signal to generate an intermediate frequency signal; an IF filter to pass a predetermined frequency component of the intermediate frequency signal; a controlling part which adjusts, according to a frequency band of the intermediate frequency signal, the frequency band of the IF filter, and adjust, according to a center frequency set in the IF filter that fluctuates with the adjustment, a center frequency of the intermediate frequency signal to be inputted in the IF filter; and a demodulating part to demodulate a frequency component of the intermediate frequency signal outputted after passing through the IF filter.

1. Technical Field
The present invention relates to a signal receiving device and signal receiving method to generate and demodulate an IF (Intermediate Frequency) signal by combining a receiving RF (radio frequency) signal and a local oscillating signal.
2. Description of Related Art
Conventionally a signal receiving device is known wherein an IF filtering circuit is equipped to receive an RF signal, and generate an IF signal of an intermediate frequency by mixing the RF signal and a local oscillating signal so as to filter the IF signal. As an IF filtering circuit, generally an active filter is used wherein a resistance and a condenser are set as a filter constant. A resistance value and a capacity value of a condenser are optimized according to a format of an RF signal to receive, an IF frequency, a passing bandwidth, an out-of-band attenuation, or the like.
For example, in order to able to receive a plurality of RF signals having different bandwidths required with a signal receiving device, a method is known wherein the signal receiving device is installed with a plurality of IF filtering circuits so as to select an optimal IF filtering circuit for an RF signal to receive (Patent Literature 1).
Patent Literature 1: Japanese Patent Kokai No. 2002-217768

Signal receiving device and signal receiving method


Disclosed is a central vacuum system. The central vacuum system comprises a first vacuum device, a second vacuum device, and a hose connected between the first vacuum device and the second vacuum device; the first vacuum device and the second vacuum are controlled by a linked switch, interior of the hose remains positive or slightly negative pressure. A self-operated differential pressure regulating valve arranged at the end of the hose is capable of generating corresponding air resistance under different airflow rate so as to maintain the interior pressure of the hose at a stable slightly positive or negative pressure.

There are two common vacuum systems available, one including a motor placed in the same room with the fan, the filter, and the suction port, e.g., household vacuum cleaner; the other including a motor, a fan and a filter placed separately from the suction port, e.g., central vacuum system. These two kinds of vacuum systems have their advantages and disadvantages respectively. The household vacuum cleaners, especially the handheld vacuum cleaner, have the advantages of short pipelines, low power, and lightness. However, they also have disadvantages including loud indoor noise, small filtering area, and more cleaning difficulty. Even worse, they may cause the pollution of dust re-entrainment. The central vacuum system is on the opposite side of the household vacuum cleaner. It requires greater host power and bulky movable hose. However, the central vacuum system has advantages including larger filtering area, easier cleaning, lower indoor noise. Furthermore, the central vacuum system will not stir up the dust re-entrainment.


A rotary-to-reciprocating linear drive conversion device is linked to drive moveable elements of a multi-unit fruit juice extraction machine. At least two co-rotating members drive a reciprocating transverse member by means of respective protruding force-transfer posts of the co-rotating members rotating while disposed to slidingly engage in the groove, so that the rotation of the co-rotating members results in reciprocal movement of the transverse member, and of elements of the multi-unit fruit extraction machine linked thereto.

The present patent of invention refers to "A LINEAR ACTUATION DRIVE SYSTEM FOR MULTI-UNIT FRUIT JUICE EXTRACTION MACHINES. As the nomenclature indicates, embodiments of the present invention have been developed to be used in equipment for extraction of juice from citrus fruit such as orange, tangelo, grapefruit, lemon, lime, tangerine, mekan, ponkan, and other non-citrus fruit of round and semi-spherical shapes. Also, in other various embodiments in other types of machines, an actuation system of the present invention is utilized to provide a reciprocating linear force obtained from a rotary motion sub-assembly. Important characteristics of the systems, apparatuses and methods of the present invention include the fact that conjugated circular (i.e., rotary) movement is converted into linear motion. Embodiments of the present invention are substantially compact, durable, simple, generate low noise, work smoothly without impact and have high efficiency, and in so operating reduce installed power needs and consequentially energy demands.

Linear actuation drive system for multi-unit fruit juice extraction machines

Abstract: The elements of the multi-unit fruit extraction machine include opposing sets of a plurality of matched peeler cups, forming matched pairs of opposing peeler cups, each peeler cup comprising a plurality of outwardly extending blades cooperatively intermeshing with a corresponding plurality of outwardly extending blades of an opposing peeler cup of the matched pair, one of said cups additionally comprising a filter device.


A machine and method for high speed production of circuit patterns on silicon wafers or similar substrates may be used for applications including printing Integrated Circuit (IC) packaging patterns onto wafers prior to separating IC chips. Projection camera(s) simultaneously project image(s) onto substrate(s) carried on an X, Y, θ stage. The projection camera(s) may include independent alignment systems, light sources, and control of focus, image placement, image size, and dose. In one embodiment, each camera includes a 6-axis reticle chuck that moves a reticle to correct image-to-substrate overlay errors. In-stage metrology sensors and machine software establish and maintain the correct relationship among the machine's coordinate systems. Thus, two or more projection cameras can print simultaneously even when substrates are slightly misplaced on the X, Y, θ stage.

Since the early 1960's, semiconductor wafer manufacturing has relied on step-and-repeat imaging to reproduce circuit patterns rapidly and at low cost. In step-and-repeat photolithography machines, a reticle that has one or a few circuit patterns on it is projected onto the semiconductor wafer through a lens. 4× reduction optics have been the most popular, but reductions of 20×, 10×, 5×, 2× and 1× have been used depending on the application. Even a few magnifying projection machines have been built. A substrate, usually a silicon wafer, is moved in a step-and-repeat manner by an X, Y stage. When the stage stops, a shutter is opened, light passes through the reticle and reduction lens, and the reticle image is quickly transferred to a photosensitive film on the substrate. For nearly 40 years, this method has been the most productive way to replicate Integrated Circuit (IC) chip patterns.
Recently, this step-and-repeat technique for imaging circuit patterns on a substrate has found utility in packaging of high density IC chips. At today's density of interconnect and value for one microprocessor chip, high yield projection methods are replacing contact printing as the photocopying method of choice.

High speed lithography machine and method