This invention relates to a process for preparing (meth)acrylic acid, whereby turndown control is utilized to maintain optimal distillation column performance in the dehydration of aqueous (meth)acrylic acid to provide a (meth)acrylic acid solution.

This invention relates to a process for preparing (meth)acrylic acid. In particular, the present invention relates to a process for preparing (meth)acrylic acid which utilizes turndown control to maintain optimal distillation column performance in the dehydration of aqueous (meth)acrylic acid to provide crude (meth)acrylic acid.
Acrylic acid is generally prepared by the vapor phase catalytic oxidation of at least one hydrocarbon material. For instance, acrylic acid may be prepared from propylene and/or acrolein in a one or two step process. In a first step propylene is oxidized in the presence of oxygen, diluent inert gasses, water vapor, and appropriate catalysts to produce acrolein according to equation (I):
C3H6+O2xe2x86x92C2H3CHO+H2O+heatxe2x80x83xe2x80x83(I).
The acrolein is then oxidized, in a second step, in the presence of oxygen, diluent inert gasses, water vapor, and appropriate catalysts to form acrylic acid according to equation (II):
C2H3CHO+xc2xdO2xe2x86x92C2H3COOH+heatxe2x80x83xe2x80x83(II).
The acrolein may also be provided as starting material in a one step reaction (II) to produce acrylic acid.
Alternatively, propane may be used as a starting material. The propane is oxidized using appropriate catalysts, for instance, as described in U.S. Pat. No. 5,380,933 to form product acrylic acid.
Methacrylic acid is similarly prepared by the catalytic oxidation of isobutylene and/or isobutane.
The acrylic acid prepared using such vapor phase catalytic oxidation reactions is present in a mixed product gas exiting the reactor. Generally, the mixed product gas is cooled and is contacted with an aqueous stream in an absorption tower, thereby providing an aqueous acrylic acid solution which is then dehydrated in a distillation step to provide a crude acrylic acid stream. The crude acrylic acid stream can be used to produce various acrylic esters or be further purified to provide various grades of purified acrylic acid which can then be further utilized, for instance in the production of super absorbent polymer products or various other polymer materials.
Typically in the manufacture of acrylic acid there are instances wherein the aqueous acrylic acid feed rate to the distillation column and/or the aqueous acrylic acid feed stream composition fed to the distillation column changes. For instance, when the feed rate and/or composition of the aqueous acrylic acid feed stream is reduced below the maximum capacity of the system because of lower demand or as a result of variations in oxidation unit output. In a like manner, the feed rate of aqueous acrylic acid may increase as a result of increased demand or as a result of variations in the oxidation unit output. As a result, a changed amount or concentration of aqueous acrylic acid, is supplied to the distillation column, thereby leading to less or more aqueous acrylic acid being dehydrated in the distillation column and therefore the amount of crude acrylic acid produced is reduced or increased.
This can result in problems regarding maintaining optimal column performance, including adequate separation characteristics. Typically, at start up, a particular column is set to operate at a predetermined optimal vapor rate which is chosen to maintain suitable column performance. The optimal vapor rate is dependent on the distillation solvent to water ratio and distillation solvent feed rate for the system and is generally established by maintaining a predetermined distillation solvent to water ratio and distillation solvent feed rate. Also, a suitable amount of heat must be provided to the column to boil most of the distillation solvent and water overhead. Since it is generally assumed that the process will be operated at full capacity, an appropriate vapor rate is typically determined for optimal operation of the distillation column at or close to 100 percent of column capacity. Any changes from the predetermined capacity usage, i.e., changes in the aqueous acrylic acid feed or composition, may result in problems with the distillation column performance. For instance, when the feed rate of aqueous acrylic acid to a distillation column is reduced and the distillation solvent feed rate is held constant, the distillation column vapor rate is reduced and the distillation solvent to water ratio is increased. As a result, since the vapor rate is changed from its predetermined optimal value, column performance, including separation characteristics, suffers.
An additional problem may occur when product demand is reduced. Generally, if turndown control is unavailable, the manufacturer must completely shutdown to avoid excessive stockpiling of product acrylic acid which brings with it problems in storage, such as threat of polymerization, space usage and space availability. Furthermore, startup and shutdown procedures may be initiated more often.
As indicated above, the preparation and isolation of methacrylic acid proceeds by similar steps. Consequently, methacrylic acid manufacturers suffer from similar problems.
Distillation methods to remove water and impurities from aqueous (meth)acrylic acid solutions are know in the art. For instance, U.S. Pat. No. 5,785,821 discloses dehydration of an aqueous acrylic acid solution using a water insoluble solvent, e.g., toluene. The patent teaches wastewater recycle to the absorber of an acrylic acid process wherein the recycled wastewater stream has a specific composition of acetic acid (3-10 wt %), acrylic acid (0.5-5.0 wt%), and distillation solvent (0.01-0.5 wt%). Such a recycle stream, containing these specific amounts of acetic acid, acrylic acid and distillation solvent is said to enable collection of acrylic acid in the absorber at a high efficiency. However, this reference does not address the problem of distillation column turndown control in a process for preparing (meth)acrylic acid, which utilizes distillation to separate (meth)acrylic acid from water and impurities.
The present inventors have now discovered a process for preparing (meth)acrylic acid having turndown control in response to feed rate and/or composition changes in the aqueous (meth)acrylic acid stream fed to the distillation column. Such turndown control is achieved by controlling the amount of water or distillation solvent or both fed to the column to maintain a predetermined optimal vapor rate which provides optimal column performance. Furthermore, in one aspect, the invention enables obtaining additional value from process wastewater streams by utilizing such streams to adjust the water feed rate to the distillation column. This is done while maintaining suitable distillation column performance characteristics.
Accordingly, a novel process for preparing (meth)acrylic acid is described herein wherein the following advantages are provided:
(1) the ability to maintain column performance characteristics in response to feed rate and/or composition fluctuations in the aqueous (meth)acrylic acid fed to the distillation column, including the ability to avoid complete shutdown during low demand by running at reduced rates;
(2) additional value may be obtained from process wastewater streams by using them to adjust the water feed rate into the distillation column including recycling wastewater recovered from distillation column overheads directly for turndown control thereby reducing the wastewater load in the facility; and
(3) reducing yield loss in the distillation column overheads by recycling wastewater recovered from distillation column overheads directly for turndown control.
In one aspect of the present invention, there is provided a process for preparing (meth)acrylic acid, including the steps of (A) feeding an aqueous (meth)acrylic acid stream including (meth)acrylic acid to a distillation column; (B) distilling the aqueous (meth)acrylic acid stream, at a predetermined vapor rate, in the presence of at least one distillation solvent substantially insoluble in water, to form a crude (meth)acrylic acid stream, and (C) maintaining the predetermined vapor rate in response to aqueous (meth)acrylic acid fluctuation by (i) monitoring a distillation solvent to water ratio during distillation and (ii) adjusting at least one of the amount of water and the amount of distillation solvent fed to the distillation column to maintain the predetermined vapor rate.
In a second aspect of the present invention, there is provided a process for preparing (meth)acrylic acid, including the steps of (A) feeding an aqueous (meth)acrylic acid stream including (meth)acrylic acid to a distillation column; (B) distilling the aqueous (meth)acrylic acid stream, at a predetermined vapor rate, in the presence of at least one distillation solvent, substantially insoluble in water, to form a crude (meth)acrylic acid stream, and (C) maintaining the predetermined vapor rate in response to aqueous (meth)acrylic acid fluctuation by (i) monitoring a distillation solvent to water ratio during distillation and (ii) adjusting the amount of water fed to the distillation column to maintain the predetermined vapor rate, wherein at least a portion of the adjusting amount of water includes recycled waste water.
In a third aspect of the present invention, there is provided a process for preparing (meth)acrylic acid, including the steps of (A) feeding an aqueous (meth)acrylic acid stream including (meth)acrylic acid to a distillation column; (B) distilling the aqueous (meth)acrylic acid stream, at a predetermined vapor rate, in the presence of at least one distillation solvent, to form a crude (meth)acrylic acid stream, and (C) maintaining the predetermined vapor rate in response to aqueous (meth)acrylic acid fluctuation by (i) monitoring a distillation solvent to water ratio during distillation and (ii) adjusting at least one of the amount of water and the amount of distillation solvent fed to the distillation column to maintain the predetermined vapor rate.
In a fourth aspect of the present invention, there is provided a process for preparing (meth)acrylic acid, including the steps of (A) feeding an aqueous (meth)acrylic acid stream including (meth)acrylic acid and at least one polymerization inhibitor selected from 4-hydroxy-2,2,6,6-tetramethyl-piperidinyloxy and derivatives thereof to a distillation column; (B) distilling the aqueous (meth)acrylic acid stream, at a predetermined vapor rate, in the presence of at least one distillation solvent, to form a crude (meth)acrylic acid stream, and (C) maintaining the predetermined vapor rate in response to aqueous (meth)acrylic acid fluctuation by (i) monitoring a distillation solvent to water ratio during distillation and (ii) adjusting at least one of the amount of water and the amount of distillation solvent fed to the distillation column to maintain the predetermined vapor rate.

Process for preparing (meth) acrylic acid


Disclosed is an organic light emitting device and a method of manufacturing the same. The organic light emitting device includes a base rod, and a plurality of organic light emitting units. Each of the plurality of organic light emitting units includes a first electrode formed on the base rod, an organic layer formed on the first electrode, and a second electrode formed on the organic layer. The plurality of organic light emitting units are formed in longitudinal direction of the base rod and come into continuous contact with each other. The first electrode of each of the organic light emitting units comes into contact with the second electrode of each of the organic light emitting units adjoining said first electrode of each of the organic light emitting units.

An organic light emitting device using organic light emission is extensively applied to various types of lighting apparatuses because of an advantage of high brightness obtained using low voltage and also to display devices because of advantages of low voltage driving, light weight and slimness, a wide viewing angle, and a high-speed response.
The organic light emission means that electric energy is converted into light energy by using an organic substance. That is, in the case of when an organic layer is interposed between an anode and a cathode, if voltage is applied between two electrodes, holes are injected into the organic layer at the anode and electrons are injected into the organic layer at the cathode. When the injected holes and electrons meet each other, an exciton is formed. The exciton falls down to a bottom state to emit light.
For example, JP-A-2005-108643 discloses an organic light emitting device that includes a first electrode having a rod shape or a first electrode formed on a surface of a support rod, an organic layer formed on a surface of a first electrode, and a second electrode formed on a surface of the organic layer.
In connection with this, the first electrode is formed around the entire support rod, the organic layer is formed around the entire first electrode, and the second electrode is formed around the entire organic layer.
The organic light emitting device having the above-mentioned structure emits light by injection of a current, the first electrode is formed around the entire support rod, and the second electrode is formed around the entire support rod. That is, the first electrode and the second electrode are formed as a large unit cell around the support rod. Hence, there is a disadvantage in that the quantity of current injected per unit area is large.
In the case of when the first electrode and the second electrode are formed as a large unit cell around the support rod or the first electrode and the second electrode are connected in parallel, it is possible to perform low voltage driving in order to ensure required brightness. However, the quantity of current to be injected is increased. For example, in order to manufacture a device of 10 □/W and ensure 1000 □, power of 100 W is required. If driving is performed by using 5 V, a injection current of 20 A is required.

Organic light emitting device and method for manufacturing the same


A piezoelectric actuator has a satisfactory electrical connection of a common electrode and a surface electrode without increasing the size of the piezoelectric actuator, as well as a liquid discharge head and a recording device. The piezoelectric actuator includes: a ceramic substrate which is long in one direction and includes a vibrating plate, a common electrode disposed on the vibrating plate and a piezoelectric ceramic layer disposed on the common electrode and having a plurality of first through holes connected to the common electrode; a plurality of individual electrodes disposed in a region of the piezoelectric ceramic layer opposed to the common electrode; and a plurality of first surface electrodes respectively disposed inside a plurality of the first through holes in the piezoelectric ceramic layer and on a circumference of a plurality of the first through holes.

Recently, printing devices using inkjet recording method, such as inkjet printers or inkjet plotters, have been widely used in not only printers for general consumers but also industrial purposes of color filter manufacturing, such as for electronic circuit formation or liquid crystal displays, and organic EL display manufacturing.
In this type of inkjet printing device, liquid discharge heads for discharging liquid are mounted as a printing head. As an example of the liquid discharge heads, there is known one configured by stacking one upon another a passage member including a manifold (common passage) and discharge holes respectively connected from the manifold via a plurality of pressurizing chambers, and an actuator unit including a plurality of displacement elements respectively disposed so as to cover the pressurizing chambers (refer to, for example, patent document 1).
In the liquid discharge head, the displacement elements is made up of a common electrode disposed substantially over the entire surface of a piezoelectric actuator, an individual electrode opposed to the common electrode, and a piezoelectric ceramic layer held between the common electrode and the individual electrode. A connection of the common electrode and the exterior is established via a penetrating conductor disposed in the piezoelectric ceramic layer at a circumferential edge of the piezoelectric actuator and via a surface electrode formed in the circumferential edge of the piezoelectric actuator. In the liquid discharge head, the pressurizing chambers respectively connected to a plurality of the discharge holes are arranged in a matrix shape, and the displacement elements of the actuator unit are arranged so as to cover the pressurizing chambers. Ink is discharged from the individual discharge holes by displacing these displacement elements, thus permitting printing at a resolution of, for example, 600 dpi in a main scanning direction.

Piezoelectric actuator, liquid discharge head, and recording device


In one example a base station for an electronic device comprises a charging station, an audio interface, logic, at least partially including hardware logic, configured to detect a first electronic device within a geographic region proximate the charging device, and in response to detecting the first electronic device 100, to establish a communication link with the first electronic device via a wireless communication channel, activate the audio interface to receive audio input. Other examples may be described.

The subject matter described herein relates generally to the field of electronic devices and more particularly to an intelligent base station for electronic devices.
Many electronic devices such as laptop computers, netbook style computers, tablet computers, mobile phones, electronic readers, and the like have communication capabilities, e.g., voice and text messaging, built into the devices. In some circumstances it may be useful to communicate with such electronic devices using an interface on ancillary electronic devices such as headsets, computer-equipped glasses, or the like. Such ancillary electronic devices tend to be compact, have limited battery power, and therefore require frequent recharging, during which time they are not useful.
Accordingly additional systems and techniques to provide for intelligent ancillary electronic devices may find utility.


This invention has as its object to provide an image processing apparatus and method which can efficiently compress an image while maintaining high image quality, and a storage medium for implementing the method. To accomplish this, an apparatus has a text area detector (101) for extracting a text area from multi-valued image data, and generating text area coordinate data (109) as position data of the text area, a binarization unit (102) for generating binary image data (108) by binarizing multi-valued image data of the text area, a color computation unit (103) for generating text color data (110) by computing a representative color of the text area, a text paint unit (104) for generating non-text multi-valued image data A by converting multi-valued image data of the text area using multi-valued image data of an area other than text, a reduction unit (105) for generating reduced non-text multi-valued image data by lowering the resolution of the non-text multi-valued image data, a JPEG compression unit (106) for compressing the non-text multi-valued image data by JPEG, and an MMR compression unit for compressing the binary image data of the text area by MMR.

In recent years, digital documentation has advanced along with the prevalence of scanners. In order to store a digital document in a full-color bitmap format, for example, an A4-size document amounts to about 24 Mbytes at 300 dpi, and a huge memory size is required. Such large-size data is not suitable for sending it as an attachment file of an e-mail message. To solve this problem, it is a common practice to compress a full-color image, and JPEG is known as a compression method for such purpose. JPEG is very effective to compress a natural image such as a photo or the like, and can assure high image quality. However, when a high-frequency portion such as a text portion is compressed by JPEG, image deterioration called mosquito noise is generated, and the compression ratio is low. Hence, the image is broken up into some areas to generate JPEG-compressed data of a background portion except for a text area, and MMR-compressed data of a text area portion with color information. Upon decompression, the individual data are decompressed and combined to express an original image.
However, a compression ratio that can be realized by the aforementioned method while maintaining high image quality is not high enough. Also, information of characters emphasized in red in black character text is lost. That is, when an image containing a text portion using two or more colors is compressed by the above compression method and the compressed image is expanded, the number of colors of the text portion contained in the expanded image is reduced to one.


A pulsed dynamic logic environment metric measurement circuit provides self-referenced, low area/cost and low power measurement of circuit environment metrics, such as supply voltage. A cascade of dynamic logic stages is clocked with a pulse having a width substantially independent of an environment metric to which the delay of the dynamic logic stages is sensitive. The number of dynamic logic stages that evaluate within a given pulse provides a direct measure of the pulse width, and thus the value of the circuit metric. The pulse may be generated from a logical exclusive-OR combination of a clock signal provided from two circuit paths that differ in sensitivity to the environment metric to be measured. One circuit path may have a delay substantially determined only by wire delay, which is not substantially sensitive to circuit environment metrics such as power supply voltage.

1. Field of the Invention
The present invention is related to measurement circuits for measuring metrics such as circuit environment variables, and more particularly to a dynamic logic metric measurement circuit.
2. Description of Related Art
Environmental measurement circuits are finding application in integrated circuits such as processor cores, in which it is useful to evaluate and/or monitor variation in circuit environment metrics such as temperature and supply voltage. Such variations can lead to substantial changes in circuit performance and may vary rapidly. Therefore, it is desirable to make real-time measurements without increasing power consumption significantly, and without requiring large circuit area.
Existing delay-based measurement circuits typically employ a chain of static logic inverters in a delay line or ring-oscillator arrangement. The delay of the delay line is sensitive to one or more environment metrics and either the delay of the delay line or the frequency of the ring oscillator is measured to determine the value of the environment metric(s). However, frequency measurement places a limitation on the real-time (cycle-by-cycle) availability of the measurement data, as the frequency must be measured long enough to attain a desired resolution, and a typical static inverter chain delay measurement must be decoded to determine the length of the delay. Control logic and calibration/reference circuits are also typically needed in present environmental monitors so that the delay can be strongly correlated to the environmental metric that is being measured.
Therefore, it would be desirable to provide a metric measurement circuit requiring low power, small circuit area and does not require additional circuitry to decode the output. It would further be desirable to provide a metric measurement circuit that is self-referenced with respect to variations of non-measured circuit metrics.

Pulsed dynamic logic environment metric measurement circuit

International Business Machines Corporation


A heat-dissipating fan includes a casing, a stator, and an impeller. The casing includes a base supported by a plurality of ribs. The base includes an axial tube for receiving a bearing through which a shaft extends. Vanes are provided on an outer circumferential wall of the impeller. An end of the shaft is fixed to an axial seat at a center of the impeller. A magnetic member is mounted to the other end of the shaft. The magnetic member and the impeller rotate synchronously under magnetic induction. When the heat-dissipating fan is mounted on top of a heat-dissipating device, a propeller of the heat-dissipating device is driven to turn synchronously under magnetic attraction. When air currents are driven by the vanes to flow downward, great noise resulting from tangential wind effect is avoided, as the ribs are not in the air inlet area.

1. Field of the Invention
The present invention relates to a heat-dissipating fan. More particularly, the present invention relates to a heat-dissipating fan for effectively lowering noise resulting from tangential wind effect.
2. Description of Related Art
FIG. 1 illustrates a sectional view of a device, which is described in copending U.S. patent application Ser No. 11/272,678, the entire specification of which incorporated herein by reference. The device comprises a heat-dissipating device 10 and a heat-dissipating fan 20. The heat-dissipating device 10 is in direct contact with a heat-generating component for absorbing heat energy. The heat-dissipating fan 20 is mounted above the heat-dissipating device 10 for assisting in dissipation of heat.
The heat-dissipating device 10 includes a central heat-conducting member 11 and a plurality of peripheral fins 12 extending outward from the central heat-conducting member 11. The central heat-conducting member 11 includes a compartment 13 in which a propeller 14 is mounted.
The heat-dissipating fan 20 is mounted on top of the heat-dissipating device 10 in an inverted state. The heat-dissipating fan 20 includes a casing 21 and a base 23 fixedly supported by a plurality of ribs 22 in the casing 21. A stator 24 and a rotor 25 are mounted on the base 23. Magnetic members 26 and 15 are respectively mounted on the rotor 25 and the propeller 14 to provide a mutually attracting effect for allowing synchronous rotation of the rotor 25 and the propeller 14.
However, the heat-dissipating fan 20 in an inverted state generates great noise due to tangential wind effect. More specifically, the ribs 22 for fixing the base 23 must extend across the air inlet area for mounting the heat-dissipating fan 20 in the inverted state. When the rotor 25 rotates and drives air downward, the ribs 22 extending across the air inlet area create a wind barrier and thus generate turbulence, leading to great noise due to tangential wind effect.

Magnetically coupled heat dissipating fan

Sunonwealth Electric Machine Industry Co., Ltd.


A rongeur surgical instrument having an offset bayonet portion for allowing microscopic visualization of an operating field. The rongeur instrument is designed with a composite shank member that includes an offset bayonet portion that interconnects a proximate shank portion to a distal shank portion. The offset bayonet portion on the rongeur facilitates operating microscope dependent operative procedures, such as microscopic osseous dissections. The offset bayonet structure maintains the mechanical objective of actuating the bite-end of the rongeur via angled shank portions on the stationary and movable shank members of the rongeur. The offset bayonet structure is applied to a curette surgical instrument for allowing microscopic visualization of an operating field when using this type of instrument.

The operating microscope has revolutionized the surgical approach to many neurosurgical diseases by providing magnification, binocular vision and excellent lighting in the depths of surgical wounds, and thus facilitating operative procedures which would otherwise be impossible. These microscope dependent operative procedures occasionally involve microscopic bone dissection and the use of osseous dissection instrumentation. While microsurgical instrumentation has been readily available for work with soft tissue, tumor removal and deep suturing, suitable microsurgical osseous instrumentation is not readily available. The task of microscopic bone dissection has been done with bone dissection instruments which are large and awkward to use. The available bone dissection instruments, commonly referred to as rongeurs, are designed to exert large forces for cutting the hard bone material, which results in the large size of the instrument. Whether the bone dissection task requires the use of the microscope or not, the bite-end, including the punch and footplate of the rongeur must be designed to withstand the forces which a surgeon applies to effect the removal of the bone. However, when performing a microsurgical procedure which requires microsurgical removal of osseous material, it is extremely important that the surgeon have a surgical tool that does not require the surgeon's hand to be in the operating field which may impede visualization through the operating microscope. The known commercially available ronguers are designed for use in non-operating microscope environments, and when used in a microsurgical osseous dissection procedure, the surgeon must cope with the problem. By example, rongeur instruments which are commonly used by surgeons in neurosurgical procedures are available from Ruggles Corp. in North Quincy, Mass. (U.S.A.).
The closest prior art patents concerns the following U.S. patents:
______________________________________ U.S. Pat. No. Inventor Date of Issue ______________________________________ 984,756 P. Frisch Feb. 21, 1911 2,691,370 F.J. Wallace Oct. 12, 1954 2,790,437 W.C. Moore Apr. 30, 1957 4,201,213 P.R. Townsend May 06, 1980 4,574,803 K. Storz Mar. 11, 1986 4,777,948 D.W. Wright Oct. 18, 1988 4,990,148 Worrick, III et al. Feb. 05, 1991 ______________________________________
These patents are of interest for teaching the basic shape of the ronguers and appear to be cumulative of the commercially available surgical instrumentation. The patents also teach improvements in the surgical rongeur instrumentation field, see for example U.S. Pat. No. 4,990,148 to Worrick, III et al., teaching an improved footplate, also termed anvil, for a rongeur. U.S. Pat. No. 2,691,370 is of interest for its teaching of an instrument for use with a telescope as a means to obviate problems associated with visualization of the field of operation in heart surgery. These patents, and known commercially ronguers in the prior art have not addressed the visual obstruction problem encountered by neurosurgeons when using these surgical instruments to perform microsurgical osseous dissections.
Thus, a need is seen to exist for a surgical instrument that has structural feature which assures that a surgeon's hand not be in the operating field, and thus facilitate unimpeded visualization by the surgeon through an operating microscope during a microsurgical osseous dissection procedure. In particular, a need is seen to exist for a rongeur having a shank portion designed with an offset portion (bayonet-like, and hereinafter referred to as offset bayonet portion) that obviates the visual obstruction problem encountered during a microsurgical procedure when using presently commercially available rongeurs.
While the rongeur surgical instrument is the preferred embodiment of the present invention, a need is also seen for other surgical instrument, such as a curette, to embody the same type of offset bayonet portion on a composite shank member of the instrument to obviate visual obstruction problems encountered when using them in a microsurgical procedure.

Rongeur apparatus having an offset bayonet and method of use with microscope during microsurgery


Fabrication of electronic devices in the “metal layers” of semiconductor devices. Each metal layer includes a dielectric layer that supports a conductive layer, which includes electrically conductive pathways and electronic devices. The metal layers are stacked on top of each other such that the dielectric layers separate the adjacent conductive layers. The electronic devices may be passive devices such as resistors. The resistors are formed by depositing metal onto the dielectric layer and then implanting the metal with oxygen. The conductive layer may be formed of materials such as copper and aluminum.

Semiconductor fabrication involves complex processes for creating integrated devices within a semiconductor wafer and connecting the integrated devices so that they can communicate with each other. Generally speaking, semiconductor fabrication is divided into two phases of processing: front-end and back-end processing. Front-end processing relates to the process steps that form the integrated devices within the surface of semiconductor wafer substrates. Integrated devices may include active electrical devices such as transistors and passive electrical devices such as capacitors, inductors, and resistors. The front-end process steps include, but are not limited to, photolithography processes, etching processes, and doping or implanting processes. Back-end processing occurs after the completion of the front-end processing steps. The back-end processing steps form multiple and stacked "metal layers" on top of a semiconductor wafer. Each metal layer includes electrically conductive traces for connecting various integrated devices within the semiconductor wafer. A dielectric layer formed of, for example, an oxide separates each of the metal layers and also provides for connectivity between each metal layer through conductive vias. Salicidation processes connect the conductive traces of the metal layers to the integrated devices within the semiconductor substrate. Salicidation may use a material such as a silicide-metal alloy (e.g., nickel or cobalt).
Current semiconductor devices increasingly use resistors to control the timing of transmitted signals within various integrated devices and electrical components. These resistors are formed in the semiconductor wafer using front-end processing steps. Such resistors may be poly-silicon and/or island resistors. Polysilicon resistors are formed on top of a semiconductor wafer substrate and gain a certain resistance through doping or implanting processes. For example, polysilicon may be doped with a material such as boron or arsenic. On the other hand, island resistors are formed within a semiconductor wafer substrate.
Unfortunately, real estate in a semiconductor wafer substrate is usually very limited. The need to create passive components for e.g., resistors and capacitors on Si substrates makes it very challenging to squeeze more transistors onto a wafer substrate. In view of the foregoing, there are continuing efforts to provide improved techniques for fabricating electrical devices, such as resistors, into semiconductor circuits.

Techniques for forming passive devices during semiconductor back-end processing


A circuit board (14) on which the electronic components (2,3) providing power to a series of light sources (6) is positioned as near as possible to light sources in order to minimise parasitic energy losses which would be introduced by lengths of wiring. The light sources (5) are usually elongate tubular Cold Cathode Fluorescent Tubes arranged parallel to one another in a single plane and the circuit board (14) may be mounted directly over the light sources, towards one end of the tubes. Standard PCB board-to-board connectors (12) may be provided at an edge of the circuit board (14) and a further circuit board (10) provided with a series of conductive tracks may provide both a mechanical and electrical connection between the circuit board (14) and the light sources (5). A power distribution method is also disclosed in which both current and temperature of the light sources are monitored and regulated in order to extend the lifetime of the light sources (5) and to stabilize their brightness.

Certain types of display apparatus, such as Liquid Crystal Display (LCD) screens used as computer screens or television screens, require backlighting in order to make display elements on the screen visible, or more easily visible, to a viewer of the display unit.
Existing "flat" screen display units, for example LCD display screens, may be single-layer display (SLD) units having a single display layer or single planar array of liquid crystal pixels, or multi-layer display (MLD) units in which a number of planar arrays of LCD pixels are aligned in a stacked or sandwiched arrangement. Multi-layered display (MLD) units provide a significant improvement over existing single layer display (SLD) units or displays. MLD units may be used to nest display content over spacially displaced or stacked layers to provide an enhanced mechanism for information absorption and analysis by users. An example of an existing multi-layer display is discussed for example in WO9942889A.
Existing MLD units require a significant amount of light to illuminate images on the foreground layer (closest to the viewer) through the previous or lower layers. Often cold cathode fluorescent lamps (CCFT) are used to provide the backlight in SLD and MLD LCD display units and these require supporting circuitry to generate an initial high starting voltage and a subsequent lower maintenance voltage once the lamps are in sustained discharge mode. This support circuitry and the tubes generate excess heat within the display apparatus and due to the proximity of the power supply wires required, power is wasted through currents produced as a result of parasitic capacitive coupling. These problems result in a need to provide a relatively high capacity and quality power supply in existing backlit display apparatus and often also results in the need to incorporate cooling components to remove the excess heat produced.
In CCFT lamps, ultra-violet (UV) light is produced via an electrical discharge passing through Argon and Mercury vapour in the lamp. The UV light reacts with a phosphor coating on the inside of the glass lamp which converts the UV light to visible light. The phosphor blend determines the spectral content of the visible light produced by the lamp.
A high voltage is required to initiate the self-sustaining electrical discharge through the gas vapour and, once started, a lower voltage is required to keep the discharge going. Power is supplied to the lamp through a ballast capacitor which ensures that the power supply sees the lamp as a linear electrical load. The total luminous flux produced by the lamp is dependent on the magnitude of the current through the lamp and the cold spot temperature of the lamp. The optimal temperature range for the lamp is between about 45 and 55° C. while the optimal current range is between about 5 and 7 mA. If the temperature and/or current are outside these ranges then the light output and life of the lamp will decrease.
MLD units have many more lamps than SLD units. For example, an MLD unit may have between 24 and 27 lamps. Conventionally, wires are used to attach an inverter to a lamp (or set of lamps) to its power supply. Two wires are required per lamp which results in a large number of wires which is cumbersome, messy, produces excessive Electromagnetic Interference (EMI) and results in power loss through the above mentioned capacitive coupling, particularly in MLD units because of the increased number of lamps.
U.S. Pat. No. 6,326,738B discloses a backlighting system for an SLD unit in which the ballast capacitor is mounted on the circuit board substrate to which one end of the lamp is connected, thereby reducing the number of wires required. This system allows two wires to be used to supply power to all of the lamps in a backlighting system but results in bright and dark spots and variance as power can not be regulated easily to ensure that each lamp receives the same amount of power. Power is also lost in this system due to the introduced parasitic capacitance between the supply wires and the metallic enclosure which is required. Furthermore, the system disclosed requires higher rated electronic components such as inverters which are physically larger and more expensive.
It is therefore an object of the present invention to provide a backlighting system which goes at least some way towards overcoming the above disadvantages or which will at least provide the public with a useful choice.
All references, including any patents or patent applications cited in this specification are hereby incorporated by reference. No admission is made that any reference constitutes prior art. The discussion of the references states what their authors assert, and the applicants reserve the right to challenge the accuracy and pertinency of the cited documents. It will be clearly understood that, although a number of prior art publications are referred to herein, this reference does not constitute an admission that any of these documents form part of the common general knowledge in the art, in New Zealand or in any other country.
It is acknowledged that the term 'comprise' may, under varying jurisdictions, be attributed with either an exclusive or an inclusive meaning. For the purpose of this specification, and unless otherwise noted, the term 'comprise' shall have an inclusive meaning—i.e. that it will be taken to mean an inclusion of not only the listed components it directly references, but also other non-specified components or elements. This rationale will also be used when the term 'comprised' or 'comprising' is used in relation to one or more steps in a method or process.


An endoscopic treatment tool is provided which includes: a grasping portion that has a first shoulder portion and second shoulder portion; a current-carrying portion that protrudes out from a distal end of each of the first and second shoulder portions; a pivot portion that is disposed in the distal end of the first shoulder portion so as to protrude in substantially the same direction as the longitudinal direction of the first shoulder portion, the distal end of the pivot portion being provided with an insulating portion; a wire that is connected to the grasping portion; a sheath which has a tubular shape, and into which the wire and grasping portion are inserted; a main body to which the sheath is fixed; and a sliding portion which is disposed to move in the longitudinal direction of the main body in a sliding manner, and to which the wire is connected.

1. Field of the Invention
The present invention relates to an endoscopic treatment tool that is used by being inserted into body cavities in a transendoscopic manner and being supplied with high-frequency current.
2. Description of Related Art
In the past, for the purpose of incision of polyps or the like, there have been known endoscopic treatment tools in which high-frequency current is supplied to a grasping portion having bifurcated distal ends. In the grasping portion of the treatment tools, the bifurcated distal ends are configured to have the same lengths in order to completely remove target tissues by high-frequency treatment (see JP-A-5-42167, for example).
In order to completely remove target tissues such as polyps, it is necessary to control the direction of the grasping portion so that the base of the tissue is disposed between the bifurcated distal ends. The treatment tool is used by being inserted into a channel provided along a scope of an endoscope. Operators such as a physician usually operate the scope, not the treatment tool. Therefore, when operators manually locate the grasping portion, the operators move one of the distal ends of the grasping portion to press against a tissue adjacent to the target tissue and rotate the scope itself about the one distal end.
However, there are many irregularities around the tissue such as polyps. In the case of the treatment tool disclosed in JP-A-5-42167, even a trial to move the one distal end of the grasping portion to press against the adjacent tissue may result in the other distal end making simultaneous contact with the adjacent tissue. In this case, it becomes difficult or impossible to rotate the grasping portion, thereby causing problems in locating the grasping portion.


A plurality of methods for achieving the softer handoff process such that the performance of a system is improved. A first method is based on delaying the softer handoff process. A second method is based on reducing the power of transmissions from the sector having the weakest signal strength. A third method is based on eliminating transmissions from the sector having the weakest signal strength. In all three methods, reverse link demodulation in each sector may continue with or without the transmission of the forward link. In all three methods the operation could be based on the signal strength of the reverse link signal or the forward link. It is also possible to combine two or more of these methods to create a hybrid method.

I. Field of the Invention
The present invention relates to communication systems, particularly to a plurality of methods for reducing the average transmit power from a sectorized base station.
II. Description of the Related Art
In a code division multiple access (CDMA) cellular telephone system or personal communications system, a common frequency band is used for communication with all base stations in a system. The common frequency band allow simultaneous communication between a mobile unit and more than one base station. Signals occupying the common frequency band are discriminated at the receiving station through the spread spectrum CDMA waveform properties based on the use of a high speed pseudonoise (PN) code. The high speed PN code is used to modulate signals transmitted from the base stations and the mobile units. Transmitter stations using different PN codes or PN codes that are offset in time produce signals that can be separately received at the receiving station.
In an exemplary CDMA system, each base station transmits a pilot signal having a common PN spreading code that is offset in code phase from the pilot signal of other base stations. During system operation, the mobile unit is provided with a list of code phase offsets corresponding to neighboring base stations surrounding the base station through which communication is established. The mobile unit is equipped with a searching element that allows the mobile unit to track the signal strength of the pilot signal from a group of base stations including the neighboring base stations.
A method and system for providing communication with the mobile unit through more than one base station during the handoff process are disclosed in U.S. Pat. No. 5,267,261, issued Nov. 30, 1993, entitled "MOBILE ASSISTED SOFT HANDOFF IN A CDMA CELLULAR TELEPHONE SYSTEM," assigned to the assignee of the present invention. Using this system, communication between the mobile unit and the end user is uninterrupted by the eventual handoff from an original base station to a subsequent base station. This type of handoff may be considered as a "soft" handoff in that communication with the subsequent base station is established before communication with the original base station is terminated. When the mobile unit is in communication with two base stations, a single signal for the end user is created from the signals from each base station by a cellular or personal communication system controller.
Mobile unit assisted soft handoff operates based on the pilot signal strength of several sets of base stations as measured by the mobile unit. The Active Set is the set of base stations through which active communication is established. The Neighbor Set is a set of base stations surrounding an active base station comprising base stations that have a high probability of having a pilot signal strength of sufficient level to establish communication. The Candidate Set is a set of base stations having a pilot signal strength of sufficient level to establish communication.
When communications are initially established, a mobile unit communicates through a first base station and the Active Set contains only the first base station. The mobile unit monitors the pilot signal strength of the base stations of the Active Set, the Candidate Set, and the Neighbor Set.
When a pilot signal of a base station in the Neighbor Set exceeds a predetermined threshold level, the base station is added to the Candidate Set and removed from the Neighbor Set at the mobile unit. The mobile unit communicates a message to the first base station identifying the new base station. A cellular or personal communication system controller decides whether to establish communication between the new base station and the mobile unit. Should the cellular or personal communication system controller decide to do so, the cellular system controller sends a message to the new base station with identifying information about the mobile unit and a command to establish communications therewith. A message is also transmitted to the mobile unit through the first base station. The message identifies a new Active Set that includes the first and the new base stations. The mobile unit searches for the new base station transmitted information signal and communication is established with the new base station without termination of communication through the first base station. This process can continue with additional base stations.
When the mobile unit is communicating through multiple base stations, it continues to monitor the signal strength of the base stations of the Active Set, the Candidate Set, and the Neighbor Set. Should the signal strength corresponding to a base station of the Active Set drop below a predetermined threshold for a predetermined period of time, the mobile unit generates and transmits a message to report the event. The cellular or personal communication system controller receives this message through at least one of the base stations with which the mobile unit is communicating. The cellular or personal communication system controller may decide to terminate communications through the base station having a weak pilot signal strength.
The cellular or personal communication system controller upon deciding to terminate communications through a base station, generates a message identifying a new Active Set of base stations. The new Active Set does not contain the base station through which communications are to be terminated. The base stations through which communication is established send the message to the mobile unit. The cellular or personal communication system controller also communicates information to the base station to terminate communications with the mobile unit. The mobile unit communications are thus routed only through base stations identified in the new Active Set.
Because the mobile unit is communicating with the end user though at least one base station at all times throughout the soft handoff processes, no interruption in communications occurs between the mobile unit and the end user. A soft handoff provides significant benefits in its inherent "make before break" communication over conventional "break before make" techniques employed in other cellular communication systems.
A typical cellular or personal communication system contains some base stations having multiple sectors. A multi-sectored base station comprises multiple independent transmit and receive antennas. The process of simultaneous communication with two sectors of the same base station is called softer handoff. The process of soft handoff and the process of softer handoff are the same from the mobile unit's perspective. However the base station operation in softer handoff is different from soft handoff. When a mobile unit is communicating with two sectors of the same base station, the demodulated data signals of both sectors are available for combination within the base station before the signals are passed to the cellular or personal communication system controller. Because the two sectors of a common base station share circuitry and controlling functions, a variety of information is readily available to sectors of a common base station that is not available between independent base stations. Also two sectors of a common base station send the same power control information to a mobile unit (as discussed below).
In a cellular or personal communication system, maximizing the capacity of the system in terms of the number of simultaneous telephone calls that can be handled is extremely important. System capacity in a spread spectrum system can be maximized if the transmitter power of each mobile unit is controlled such that each transmitted signal arrives at the base station receiver at the same level. In an actual system, each mobile unit may transmit the minimum signal level that produces a signal-to-noise ratio that allows acceptable data recovery. If a signal transmitted by a mobile unit arrives at the base station receiver at a power level that is too low, the bit-error-rate may be too high to permit high quality communications due to interference from the other mobile units. On the other hand, if the mobile unit transmitted signal is at a power level that is too high when received at the base station, communication with this particular mobile unit is acceptable but this high power signal acts as interference to other mobile units. This interference may adversely affect communications with other mobile units.
Therefore to maximize capacity in an exemplary CDMA spread spectrum system, the transmit power of each mobile unit within the coverage area of a base station is controlled by the base station to produce the same nominal received signal power at the base station. In the ideal case, the total signal power received at the base station is equal to the nominal power received from each mobile unit multiplied by the number of mobile units transmitting within the coverage area of the base station plus the power received at the base station from mobile units in the coverage area of neighboring base stations.
The path loss in the cellular or personal communication radio channel can be characterized by two separate phenomena: average path loss and fading. The forward link, from the base station to the mobile unit, operates on a different frequency than the reverse link, from the mobile unit to the base station. However, because the forward link and reverse link frequencies are within the same frequency band, a significant correlation between the average path loss of the two links exists. On the other hand, fading is an independent phenomenon for the forward link and reverse link and varies as a function of time.
In an exemplary CDMA system, each mobile unit estimates the path loss of the forward link based on the total power at the input to the mobile unit. The total power is the sum of the power from all base stations operating on the same frequency assignment as perceived by the mobile unit. From the estimate of the average forward link path loss, the mobile unit sets the transmit level of the reverse link signal. Should the reverse link channel for one mobile unit suddenly improve compared to the forward link channel for the same mobile unit due to independent fading of the two channels, the signal as received at the base station from this mobile unit would increase in power. This increase in power causes additional interference to all signals sharing the same frequency assignment. Thus a, rapid response of the mobile unit transmit power to the sudden improvement in the channel would improve system performance.
Mobile unit transmit power is also controlled by one or more base stations. Each base station with which the mobile unit is in communication measures the received signal strength from the mobile unit. The measured signal strength is compared to a desired signal strength level for that particular mobile unit. A power adjustment command is generated by each base station and sent to the mobile unit on the forward link. In response to the base station power adjustment command, the mobile unit increases or decreases the mobile unit transmit power by a predetermined amount. By this method, a rapid response to a change in the channel is effected and the average system performance is improved.
When a mobile unit is in communication with more than one base station, power adjustment commands are provided from each base station. The mobile unit acts upon these multiple base station power adjustment commands to avoid transmit power levels that may adversely interfere with other mobile unit communications and yet provide sufficient power to support communication from the mobile unit to at least one of the base stations. This power control mechanism is accomplished by having the mobile unit increase its transmit signal level only if every base station with which the mobile unit is in communication requests an increase in power level. The mobile unit decreases its transmit signal level if any base station with which the mobile unit is in communication requests that the power be decreased. A system for base station and mobile unit power control is disclosed in U.S. Pat. No. 5,056,109 entitled "METHOD AND APPARATUS FOR CONTROLLING TRANSMISSION POWER IN A CDMA CELLULAR MOBILE TELEPHONE SYSTEM," issued Oct. 8, 1991, assigned to the Assignee of the present invention.
Base station diversity at the mobile unit is an important consideration in the soft handoff process. The power control method described above operates optimally when the mobile unit communicates with each base station through which communication is possible. In doing so, the mobile unit avoids inadvertently interfering with communications through a base station receiving the mobile unit's signal at an excessive level but unable to communicate a power adjustment command to the mobile unit because communication is not established therewith.
Each base station transmits an equal amount of power to each mobile unit regardless of the location of the mobile unit. Thus as a mobile unit moves toward the edge of the base station coverage area, the signal strength of the forward link signal at the mobile unit falls. Also as the mobile unit moves to the edge of the coverage area of the current base station, the mobile unit generally moves closer to the base station coverage area of other base stations. Thus as the mobile unit moves toward the edge of the base station coverage area, the signal level from the current base station falls while interference from other base stations increases. The falling signal level also means that the signals are more sensitive to thermal noise and the noise created by the receiving circuitry in the mobile unit. This situation may be aggravated by a mobile unit located within an area where two sectors of a common base station overlap.
In a case where a set of base stations is operating at near capacity, the mobile unit located at the edge of the base station coverage area and within the coverage area of two sectors of the same base station may experience a drop in signal-to-noise ratio such that the quality of communications is degraded. The softer handoff process provides information to the base station that can be used to improve this situation. The improvement can be created by decreasing the average power transmitted by each sector of a base station. By decreasing the average power transmitted by each sector of a base station, the interference to all mobile units is reduced. Thus the interference to the mobile units at the edge of the coverage area is also reduced causing an increase in the average signal-to-noise ratio of mobile units a the edge of the coverage area.
In a system having soft and softer handoff capabilities and having neighboring base stations at or near capacity, a given amount of base station power is divided among the forward link signals such that each additional forward link signal transmitted from a base station decreases the power of other forward link signals. In a system operating at capacity, compare a base station having two sectors in which every mobile unit in the coverage area of the base station is in softer handoff mode to a base station having two sectors in which no mobile unit is in softer handoff mode. In the base station having every mobile unit in softer handoff, each forward link signal from each sector is transmitted at one-half of the power of each forward link signal from the base station having no mobile unit in softer handoff. Because, in the case where every mobile station is in softer handoff, the signals from each sector are combined in the mobile unit, the signal-to-interference ratio after combining is equal to the no handoff case if and only if each mobile unit is well served by both sectors.
However, in reality not every mobile station in a sectorized base station is well served by each sector. Thus, by determining which mobile units in a softer handoff are not being well served by one of the two sectors, the power transmitted from the weakest sector to a poorly served mobile units can be reduced or eliminated. A fewer number of signals to be transmitted from a sector means more power available for the remaining signals. When the base station transmits higher power forward link signals, the signal-to-interference for mobile units operating at handoff boundaries or at the edge of the coverage area is improved. Alternatively, as the number of signals is reduced, the total base station transmitter power can decrease which also results in less interference power in the system.
It is therefore the object of the present invention to improve forward link signal-to-interference ratio by reducing ineffectual forward link transmissions to mobile units in softer handoff, reducing the interference power to other mobiles and making more transmitter power available to all useful links to mobile stations.
It is therefore the object of the present invention to provide a plurality of methods to decrease the transmission power from a base station.
It is another object of the present invention to provide a plurality of methods to provide an enhanced softer handoff process to improve the forward link performance.

Method and apparatus for reducing the average transmit power from a sectorized base station


An apparatus for cleaning and chemical activation of a plurality of plate lug surfaces. The apparatus includes an ultrasonically-stirred flux vessel, an ultrasonically-stirred rinsing water vessel and a gas-blowing device contained inside a dirt collection vessel. Each vessel has an independent movement capability in the upward or downward directions, and all three vessels are mounted on a common supporting frame which allows their simultaneous horizontal displacement. When coupled to a conventional cast-on-strap machine, the apparatus allows the manufacture of pore-free cast-on-strap joints for lead-acid batteries.

A lead-acid storage battery is a device which converts chemical energy into electrical energy by means of chemical reactions taking place between a liquid electrolyte (consisting of an aqueous solution of sulfuric acid, H.sub.2 SO.sub.4), and the active materials of a plurality of lead-based positive and negative plates. These active materials are lead dioxide (PbO.sub.2) for the positive plates and sponge lead (Pb) for the negative plates.
A conventional lead-acid battery assembly consists of the cell elements, intercell connectors, a container, a cover, vent plugs and terminal posts. A cell element is formed by stacking together alternate negative and positive plates, with separators. The lugs of the negative plates in the cell element are joined together by a cast-on-strap joint. The same is done to the lugs of the positive plates in the cell element. The cast-on-strap joint of each group of plates is used to connect them in series with the plate groups of adjacent cells, in such a way that the voltage of the battery equals the sum of the voltages of the individual cells. The voltage of a single cell is nominally 2 volts, regardless of the size or quantity of plates. Therefore, a 12-volt battery has six cells and a 6-volt battery has three cells.
The steps followed to manufacture a lead-acid battery are: plate grid casting and preparation of active material pastes; paste application to the plate grids; paste curing; cell element integration operations; plate lugs joining by cast-on-strap process; subsequent battery assembly processes; electrolyte addition to battery cells; electric formation of the battery and final assembly and testing.
The present invention relates to the cast-on-strap process used to join the negative and the positive plates in the cell elements of lead-acid batteries. A casting machine commonly employed to manufacture the cast-on-strap joints comprises four working stations. At station 1, the plate groups are loaded into the machine, their lugs are turn downward and the plates are vibrated to align them up. Then, the plates are moved to station 2, where a two-step cleaning treatment is given to the surface of the plate lugs. The first step of the cleaning treatment involves brushing by means of a rotating horizontal steel brush in order to eliminate lead oxide skins and active material pastes. The second step of the cleaning treatment involves the application, at room temperature, of a film of liquid flux to the freshly brushed plate lugs surface by means of a rotating felt brush or by means of a flux-impregnated sponge. Subsequent processing at station 3 of the machine involves the manufacturing of a pair of lead-based cast-on-strap joints for each cell element, using a suitable water-cooled and preheated metallic mold. In order to do this, the mold cavities are filled, either by gravity or pressurized injection, with a lead-based molten strap alloy of a suitable chemical composition. Then, the flux-impregnated plate lugs are immersed into the molten strap alloy. The cast-on-strap joints are formed by subsequent solidification of the molten strap alloy in the strap mold. The final processing step, carried out at station 4, involves the withdrawal of the cell elements, with the cast-on-strap joints already formed, from the machine.
A characteristic feature of the cell elements, produced by the conventional cast-on-strap process just described, is the presence of a substantial amount of porosity located mainly at the interface between the plate lugs surface and the cast-on-strap joints. This porosity is easily visible in cross-sectioned cast-on-strap joints. This type of defect may result in an accelerated corrosion at the pores, with a consequent reduction in the useful life of the batteries.
In order to determine the causes of the formation of porosity in the cast-on-strap joints obtained by employing the conventional cast-on-strap process, an extensive research program was carried out. The research led to the development of the present invention. It was discovered that the pores found inside the cast-on-strap joints are due mainly to the presence on the plate lugs surface of residues of lead oxides, greases, oils, active material pastes, fluxes, residual reaction products and humidity, all of which produce substantial volumes of gas on heating in contact with the molten lead-based strap alloy. The gases generated during solidification of the cast-on-strap joints cannot be completely eliminated, especially under the fast cooling conditions existing in the metallic mold. Thus, a considerable amount of gas bubbles remain trapped inside the solidified cast-on-strap joints obtained. It was concluded that pore-free cast-on-strap joints cannot be reproducibly produced by employing a conventional cast-on-strap machine. This makes it mandatory to develop a device truly capable of producing pore-free cast-on-strap joints.
The present invention relates to an apparatus for cleaning and chemical activation of a plurality of plate lug surfaces. When this apparatus is used, coupled to a conventional cast-on-strap machine, produces pore-free cast-on-strap joints for lead-acid batteries. The apparatus is based on a process described in a previous patent application (Ser. No. 08/941,531, filed on Sep. 30, 1997). This process comprises the steps of cleaning a plurality of positive and negative plate lugs by a combined action of a liquid flux and ultrasonic vibration, water rinsing the plate lugs under ultrasonic vibration, and drying the plate lugs by gas blowing. The gas blowing occurs prior to the formation of the cast-on-strap joints. The cast-on-strap joints are formed, following the conventional cast-on-strap process, by introducing the plate lugs into a molten lead-based strap alloy contained in a strap mold and solidifying the molten strap alloy in the strap mold.
The use of the apparatus has the present invention replaces the steps of brushing the plate lugs employing a rotating steel brush and application of a film of liquid flux to the plate lugs by means of a rotating felt brush or by means of a flux-impregnated sponge. These operations are commonly carried out at the second station of a conventional cast-on-strap machine. It is an object of the present invention to provide an apparatus for the manufacture of pore-free cast-on-strap joints.
This and other objects and advantages of the present invention will become apparent from a reading of the attached specification and appended claims.

Apparatus for cleaning and drying a plurality of plate lug surfaces for producing pore-free cast-on-strap joints for lead-acid batteries


Provided herein are coil support structures and methods of retaining a printed circuit board assembly (PCBA) of a relay. In some embodiments, a bi-stable relay assembly may include a coil support structure, having a central section extending between a first end section and a second end section, and set of biasable fasteners extending from the first end section and the second end section, wherein each of the set of biasable fasteners includes a sloped engagement surface and a retention slot. The coil support structure may further include a PCBA coupled to the first and second end sections of the coil support structure, wherein the coil support structure extends within the retention slot of each of the set of biasable fasteners.

Electrical relays are devices that enable a connection to be made between two electrodes in order to transmit a current. Some relays include a coil and a magnetic switch. When current flows through the coil, a magnetic field is created proportional to the current flow. At a predetermined point, the magnetic field is sufficiently strong to pull the switch's movable contact from its rest, or de-energized position, to its actuated, or energized position pressed against the switch's stationary contact. When the electrical power applied to the coil drops, the strength of the magnetic field drops, releasing the movable contact and allowing it to return to its original de-energized position. A normally open relay, for example, is a switch that keeps its contacts closed while being supplied with the electric power and that opens its contacts when the power supply is cut off.
Some relays include a coil support and integrated PCBA. Currently, PCBAs are fixed to the coil support by screwing, riveting and similar. Therefore, what is needed is a simplified coil support and PCBA, which reduces part complexity and reduces assembly time.

Coil support structure and method of retaining PCBA of a relay


Provided are a method and apparatus for increasing task-execution speed, and, more particularly, a method and apparatus for increasing task-execution speed by compiling code to bytecodes, and executing native code in units of blocks instead of bytecodes, in which a block is a group of a series of bytecodes. The apparatus includes a receiving unit which receives a bytecode, a control unit which identifies whether the received bytecode is the last bytecode of a block, and a transmitting unit which transmits an address of a first native code of one or more native codes that correspond to one or more bytecodes included in the block based on the identification result.

1. Field of the Invention
Apparatuses and methods consistent with the present invention relate to increasing task-execution speed, and, more particularly, to increasing task-execution speed by compiling code to bytecode, and executing native code in units of blocks instead of bytecode, in which a block is a group of a series of bytecodes.
2. Description of the Related Art
Java is an object-oriented programming language that can be executed on any platform. A platform refers to hardware on which a program or software such as an operating system (OS) runs. Code written in Java is compiled into bytecode by a Java compiler, and the bytecode is executed by a Java virtual machine ported on various platforms.
Bytecode is a command language, such as a machine language, and is not dependent on a particular processor. Bytecode is executed by a virtual machine. That is, the virtual machine interprets the bytecode into corresponding native code. Since the bytecode is not limited to a particular architecture, it can run on any architecture having the Java virtual machine. Accordingly, a binary bytecode file can be executed in a platform-independent manner.
However, a major drawback of Java is execution speed. A program compiled on a particular architecture runs faster than bytecode because it runs directly on hardware without requiring a processor architecture to be emulated on another processor architecture.
With bytecode, the Java virtual machine running on a processor has to convert the bytecode into native code before starting its operation.
Various hardware or software technologies are being tried in order to increase the execution speed of the bytecode. For example, software technology such as a just-in-time (JIT) compiler or a hotspot JIT compiler, which are faster than the JIT compiler, have been used to increase the speed of the Java virtual machine. The JIT compiler accompanies compile overhead and memory overhead when generating a native processor command.
As hardware technologies for increasing the interpretation speed of bytecode, a technology of modifying processor architecture and a technology of using an external processor are being tried.
FIG. 1 is a flowchart illustrating a conventional method of converting bytecode into native code and executing the native code.
Referring to FIG. 1, a software routine running on a central processing unit (CPU) loads bytecode, and a processor transmits the bytecode or an address of the bytecode to a Java interpretation accelerator (S10). When the address of the bytecode is transmitted, the bytecode located at the address may be called.
Then, the bytecode is input to a state machine included in a bytecode interpreter, and the state machine searches a native code cache for a cached and interpreted version of the bytecode, that is, native code (S20). If the native code is found in the native code cache, its address is transmitted to the processor (S60). Accordingly, native code is sequentially executed from the native code located at the address (S70).
If the native code is not found in the native code cache, the state machine searches a bytecode-interpretation lookup table (S30). The bytecode-interpretation lookup table denotes information stored in order to map or convert bytecode. It is determined whether the bytecode exists in the lookup table (S40). If the bytecode does not exist, the process ends. If the bytecode does exist in the lookup table, an interpreted version of the native code is copied to the native code cache (S50). The processor receives an address of the native code in the native code cache (S60), and executes commands corresponding to native code, starting with a command corresponding to the native code located at the address (S70).
After native code for the finally interpreted bytecode is executed, a control right is transferred to a software or hardware routine responsible for resuming the interpretation of the next bytecode. Such a handoff is performed in the final stage of executing the interpreted bytecode.
However, since the handoff causes a performance loss due to the extra overhead, an invention that can enhance system performance by reducing the frequency of handoffs is needed.

Method and apparatus for increasing task-execution speed

THE BOARD OF REGENTS, THE UNIVERSITY OF TEXAS SYSTEM


A medical X-ray image detecting device arranged such that an X-ray image sensor comprising an x-ray fluorescent element, a solid-state image pickup device and a plurality of optical fiber bundles for optically connecting the fluorescent surface of the X-ray fluorescent element to the image pickup surface of the image pickup device, is housed in an outer casing, the medical image detecting device being characterized in that it further comprises an X-ray intensity detecting element disposed in the casing adjacent to the X-ray fluorescent element. Clear X-ray images with a constant blackening degree can be obtained by controlling X-ray radiation time using the X-ray dose calculated by integrating the X-ray intensity output from the X-ray intensity detecting element with respect to X-ray exposure time.

1. Field of the Invention
The present invention relates to a medical X-ray image detecting device, more particularly, a compact dental X-ray image detecting device inserted and used in a mouth to photograph teeth.
2. Prior Art
An X-ray photographing system for taking photographs in a mouth, wherein X-rays penetrated a tooth section in a mouth are converted into an optical image on the fluorescent surface in a compact X-ray image detecting device disposed behind the tooth section in the mouth and the optical image is projected to the image pickup surface of a solid-state image pickup device such as a CCD device via a plurality of glass fiber bundles, then the optical image is converted into a digital signal and reproduced on a monitor display, has become to be used for dental treatment.
In a conventional intra-oral (inside-mouth) X-ray radiography system, the position of an X-ray source for irradiating X-rays is set to a target tooth section and a compact X-ray image detecting device is set behind the tooth section. The X-ray tube voltage and current of the X-ray source are then set depending on the conditions of the photographing target section, the size and other factors of a patient by the operator of the photographing system. After these settings, X-rays are irradiated during a specific radiation period predetermined by the X-ray tube voltage and current.
The X-rays irradiated from the X-ray source penetrate the tooth section (target object to be photographed) and are converted into an optical image having a brightness proportionate to the dose of penetrated X-ray radiation to the fluorescent surface on an X-ray fluorescent element. The X-rays which have penetrated the X-ray fluorescent element are not only unnecessary but also harmful to a human body if the dose of exposure increases. In addition, the unnecessary X-rays sometimes cause adverse effects to the CCD device. It is therefore necessary to take countermeasures to prevent the adverse effects of the X-rays.
In addition, it is known that a conventional X-ray image detecting device adopts a method of projecting contracted optical images to the image pickup surface of a CCD device by processing the optical input or output surfaces of a plurality of glass fiber bundles for transmitting optical images so that the input or output surfaces obliquely intersect the cores of the filaments of the glass fiber bundles. As another conventional X-ray image detecting device, the image pickup surface of a CCD device is arranged parallel to the X-ray direction or disposed in a container away from an X-ray penetration area behind the fluorescent surface of a fluorescent element to avoid the adverse effects of X-rays on the CCD device (Laid-open Patent Application No. 2-249537).
As described above, when such conventional methods are used, wherein the CCD device's exposure period for the optical image on the fluorescent surface formed by the X-rays penetrated the tooth section is determined after the X-ray radiation conditions of the X-ray generator are determined according to the experience of an operator, the blackening degree of the X-ray image formed on the monitor display is not constant and the quality of the image changes at each photographing time, occasionally preventing image quality required for diagnosis from being obtained. As a result, rephotographing may frequently be required. This takes longer time for dental diagnosis and increases the dose of X-ray exposure to a patient, causing adverse effects.
The above-mentioned conventional device wherein the glass fiber bundles have surfaces obliquely intersecting the cores of the fiber filaments is conveniently used to contract an image of a target object projected to the fluorescent surface. However, the device lowers the resolution of the X-ray image reproduced, and is thus not necessarily suited for dental treatment.
In addition, until the X-rays reach the fluorescent surface from the X-ray source, a part of the X-rays is scattered when penetrating the inside of a target object such as a tooth tissue, generating scattered X-rays with low energy. Since the CCD device also senses X-rays with low energy of several keV or less and generates an electric signal, the X-ray image picked up by the CCD device and reproduced on the monitor display is subjected to external disturbance from the tooth tissue for example and the clearness of the image is lowered. This kind of scattering of X-rays cannot be avoided even when the CCD device is disposed in the detecting device to try to avoid the X-rays generated straight from the X-ray source as described above. As a result, the scattered X-rays enter the CCD device and disturb the image signal.
Furthermore, in the cases of the conventional X-ray image detecting devices, the X-rays penetrated the CCD device to the backside thereof is irradiated to a human body. This radiation of X-rays must be prevented.

Dental X-ray image detecting device with an automatic exposure function


A semiconductor device fabricating method may include forming an insulating layer on a semiconductor substrate; forming a through hole with a first depth in the insulating layer and the semiconductor substrate; forming a metal layer thereon, thereby forming a through electrode in the through hole; and exposing the through electrode by polishing the bottom surface of the semiconductor substrate.

Embodiments of the invention relate to a semiconductor device fabricating method.
FIG. 1 is a concept view of semiconductor devices in a SiP (System in a Package) arrangement according to fabricating method of the related art.
As shown in FIG. 1, the semiconductor devices in the SiP package according to the related art comprise an interposer 1, a first device 3, a second device 5, and a third device 7. The first to third devices 3, 5, and 7 can, for example, be independently selected from a CPU, SRAM, DRAM, Flash Memory, Logic LSI, Power IC, Control IC, Analog LSI, MM IC, CMOS RF-IC, Sensor Chip, application specific IC, and MEMS Chip, etc.
Between the first device 3 and the second device 5, and between the second device 5 and the third device 7, connecting means for connecting signals between the respective devices are formed, respectively. As one connecting means for connecting signals between the respective devices, there may be a through electrode. The through electrode is an electrode penetrating through the device or chip, and can perform a function electrically connecting the corresponding devices and the devices stacked on the upper surface thereof. Also, the through electrode can function perform a function electrically connecting the corresponding devices and the device(s) on the lower surface thereof.
As the materials for the through electrode, any metal with low resistance can be used. However, as compared to the diameter of the through electrode, the distance between an upper chip and a lower chip is about 10 to 50 μm. Considering aspect ratio (distance between chips or length of the through hole vs. diameter of the through hole), it is about 50:1 to 300:1. Therefore, it is difficult to form the through electrode stably connected from an upper area to a lower area.
A need exists for a method capable of efficiently and stably forming an elongated through electrode.


An optical recording medium has a substrate, and a light absorbing layer serving as a recording layer formed on the substrate. The light absorbing layer contains a metallo-phthalocyanine compound of formula (I): ##STR1## wherein M is Mn, Fe, Co, Zn or Cd; and either A.sup.1 or A.sup.2, either A.sup.3 or A.sup.4, either A.sup.5 or A.sup.6, and either A.sup.7 or A.sup.8 is --OR group or --SR group in which R is an aliphatic, aromatic or alicyclic hydrocarbon group, and the other is hydrogen; and a nitrogen-containing compound selected from the group consisting of an amino compound, an imino compound and an azo compound, each of which may have a substituent or form a ring.

1. Field of the Invention
The present invention relates to an optical recording medium and a method of producing the optical recording medium.
2. Discussion of Background
Recently overwrite type CDs (Compact Disks) have been actively developed. This is because the overwrite type CDs, unlike conventional CD, have the features that the user can record information therein as desired, and the recorded information can be reproduced therefrom by use of a commercially available CD player since the signals recorded in the overwrite type CDs satisfy the conventional CD standards for signals for recording.
An example of such an overwrite type CD is proposed in Japanese Laid-Open Patent Application 2-42652. This overwrite type CD comprises a substrate, a light absorbing layer which is provided by the spin coating of a dye on the substrate, and a metal reflection layer provided on the back side of the substrate opposite to the light absorbing light.
Another example of such an overwrite type CD is proposed in Japanese Laid-Open Patent Application 2-132656. This overwrite type CD comprises a light absorbing layer comprising a dye and is caused to satisfy the conventional CD standards for signals for recording by appropriately selecting the double refractive index and thickness of the light absorbing layer.
The overwrite type CD using dyes as disclosed in Japanese Laid-Open Patent Applications 2-42652 and 2-132656, however, do not have a sufficient light resistance for use in practice. To be more specific, these overwrite type CDs have the shortcoming that the signal characteristics thereof change, when exposed to sun light for an extended period of time, to such an extent that they cannot satisfy the conventional CD standards. This is because the properties of the dye materials used in the light absorbing layers thereof, in particular, conventional cyanine dyes, are changed when exposed to light.
In order to control such changes in the properties of the dye materials, it has been proposed to contain a light stabilizer in the light absorbing layer as disclosed in Japanese Laid-Open Patent Application 63-159090. However, when the content of the light stabilizer in the light absorbing layer is small, for instance, less than 20 wt. %, a sufficient light resistance for use in practice cannot be obtained, while when the content of the light stabilizer in the light absorbing light is large, for instance, 20 wt. % or more, the optical and/or thermal characteristics of the light absorbing layer are changed and the signal recording and reproduction characteristics of the light absorbing layer deteriorate in many respects.
As another means for improving the light resistance of the light absorbing layer, it is proposed as disclosed in Japanese Laid-Open Patent Applications 58-183296 and 58-37851 that a phthalocyanine compound, which is a dye with high light resistance, be employed as a material for the light absorbing layer. However, the solubility of the phthalocyanine compound in a solvent is too poor to form a film of the phthalocyanine compound by spin coating. In addition, it is difficult to obtain the optical characteristics required for the light absorbing layer, in particular, high refractive index, by use of such a phthalocyanine compound.
This is because the optical characteristics of the light absorbing layer depend upon the absorptivity coefficient of the layer (i.e. the absorbance per unit thickness of the layer) at a wavelength close to the wavelength of a laser beam used for recording and reproducing, so that there is required a sufficiently large absorptivity coefficient to satisfy the optical characteristics required for the overwrite type CD. However, a film layer of such a phthalocyanine compound has an absorptivity coefficient which is smaller than that of a film layer of the conventional cyanine dye. To be more specific, the absorptivity coefficient of the film layer of the phthalocyanine compound is about 1/3 to 1/2 that of the film layer of the cyanine dye.

Optical recording medium and method of producing the same


The device and methods described herein relate to the isothermal heat transport through an intermittent liquid supply to an evaporator device, thereby enabling high evaporative heat transfer coefficients. A liquid and vapor mixture flows through miniature and micro-channels in an evaporator and addresses flow instabilities encountered in these channels as bubbles rapidly expand. Additionally, a high percentage of the fins are exposed to vapor and limit the required charge of refrigerant t within the system due to effective condensate removal in the condenser.

Passive heat transfer devices, such as heat pipes, are of much interest in applications such as electronics cooling. Heat pipes are a liquid and vapor device in which liquid is pumped through capillarity from the condenser to the evaporator. The pumping effect in this device requires a wick, which produces a high pressure loss and limits the maximum heat transport distance and or power that can be supported before dry-out occurs.
Another technology node that is useful is a thermosyphon as shown in FIG. 1. In operation, liquid 104 is vaporized in an evaporator 101. The vapor then travels through a tube 102 to the condenser 100. Heat is removed from the condenser 100 causing the liquid 104 to accumulate at the bottom. The accumulated liquid 104 in the condenser is driven by gravity through a liquid line 103 back to the evaporator 101. The evaporators in these devices are typically pool boiling devices with an enhanced surface 105 that may consist of fins, a porous layer or even an etched surface. The maximum boiling heat transfer coefficient can be limited in this device because there are a finite amount of nucleation sites, and therefore a limited length of solid/liquid/vapor contact, where the heat transfer rate is the highest.
In conventional thermosyphon design, a flow pattern that enters one side of the evaporator and leaves the other side, through a series of channels is typically not used. While this general concept is widely used in most heat transfer products, the implementation in thermosyphon design for electronics is generally prohibited by the limited pressure head provided by gravity to drive the flow and flow instabilities encountered with vapor expansion in a confined channel as shown in FIG. 2. As a channel size 201 decreases to the same size of a vapor bubble 202, the expansion of the vapor causes liquid 203 to flow outwards 204, irrespective of the desired flow rate. This phenomena poses a few problems. One problem is that the pressure drop associated with high liquid velocities in a channel are quite high, especially relative to the small available pressure head in a thermosyphon device. A second problem that this phenomena can cause is that the middle of the channel is left dry and can increase in temperature, since the vapor has limited heat capacitance.


A sigma delta modulator (10) for use in codec applications provides dynamic range adjustment and avoids asymmetrical signal clipping. The modulator (10) has a summing circuit that sums a plurality of inputs, one of which is a dither component. The dither is programmably modifiable to provide enhanced performance. The dither is provided by a pseudo random number generator (100). The pseudo random number generator (100) has an n-bit shift register (106) coupled to a last code detect (108) to detect the end of a pseudo random number sequence. At that time, a new preset code can be loaded (110) into the shift register (106) to provide different dither characteristics. This allows the pseudo random number generator (100) to programmably determine the percentage of ones and zeros to add to the output signal. The dither output can be inverted (104) to shift the dither up or down.

This invention concerns a sigma delta modulator for use in a voice codec application used to convert analog voice signals to digital signals such as those used with GSM.
In quantizing operation in A/D conversion, partial missing of information in the quantized output signal is inevitable because continuously distributed sampled values in an input signal are expressed by dispersed values in the quantized output signal. This difference between the quantized output signals and the input sampled values becomes a quantizing noise which is an inherent restriction on the digital signal processing. The quantizing noise becomes a white noise which is uncorrelated with a signal to be converted if the signal is of a large level whereas the quantizing noise becomes distortion which is greatly correlated with the signal if the signal is of a relatively small level and this noise adversely affects the quality of tone when a signal is sounded in digital apparati.
A dither circuit can be used to overcome this problem. The dither circuit is provided for uncorrelating quantizing noise with a signal to be converted by superimposing dither or random noise on an input signal before A/D conversion and subtracting the dither component after the A/D conversion.
Input range adjustment is strongly desired under low power supply operation since the signal swings must be limited to the range power supply and ground rail. Some of the problems inherent in the prior art include asymmetrical signal clipping and shifting in sigma delta modulator circuits.

Dithered sigma delta modulator having programmable full scale range adjustment


A technique for fabrication of thin-film bolometric materials for use in -ohm resistance multi-detector devices. A group IB periodic table element is reactively co-sputtered with small amounts of a dopant in a reduced gas atmosphere. The reactive co-sputtering is achieved in an oxygen containing atmosphere, where the dopant has an oxide that is highly temperature dependent with an electrical resistance that varies in accordance with the oxide content of the dopant. A reduced electrical resistance of the resultant doped material is achieved.

1. Field of the Invention
The present invention generally relates to materials fabrication and more specifically, to thin-film materials having low-electrical resistance for use in bolometers.
2. Description of Prior Art
A bolometric material is a material that utilizes an electrical property (such as electrical resistance) which changes with temperature, usually used by a multi-detector device for detecting and measuring small amounts of thermal radiation. To be utilized in a multi-detector device such materials must comply with both thermal and electronic requirements.
It is important that these materials be fabricated in thin-film form to lower noise and have large thermal coefficients of resistance (TCR). An electrical requirement especially for use in low-ohm resistance multi-detector devices is that the material must also have a low electrical resistance.
Bolometric materials are manufactured from many different materials by various processes. Materials used in the prior art include: semiconductors, such as carbon; mixed oxides of nickel, cobalt, and manganese; germanium doped with gallium or indium; and indium antimonide. Different forms of these materials for bolometers are known, including a class of bolometers incorporating a capacitive element using thin films with temperature dependent electrical polarization properties. For thin film manufacture of materials such as the oxides mentioned above reactive sputtering is usually utilized. Unfortunately, there is a problem in that the prior art materials which have high TCR's also have high-electrical resistivities. Another problem is that many of the thin films, such as the above mentioned oxide films, produced by reactive sputtering are difficult to reproduce because of the disastrous effects of minute changes in deposition pressure on resultant electrical conductivity.
While the prior art has reported using bolometric materials none have established a basis for a specific method that is dedicated to the task of resolving the particular problem at hand.
What is needed in this instance is a method to reduce the electrical resistance of a material while retaining thermal characteristics for bolometer use.

Method for fabrication of thin-film bolometric material

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