In one embodiment, a method includes receiving an acoustic input signal at a speech recognizer. A user is identified that is speaking based on the acoustic input signal. The method then determines speaker-specific information previously stored for the user and a set of responses based on the recognized acoustic input signal and the speaker-specific information for the user. It is determined if the response should be output and the response is outputted if it is determined the response should be output.

Particular embodiments generally relate to speech recognition.
Speech recognition attempts to make information access easier and simpler through verbal queries and commands. These queries have historically been activated by button presses on a device, such as a smart phone. Using verbal queries allows users to make queries without typing in the query. This makes information access easier when users are busy, such as when users are in cars or simply would not like to type in the queries. After the button press is received, a speech recognizer listens to the query and attempts to respond appropriately. Even though using the button press is easier, sometimes having a user press a button to activate the speech recognizer is inconvenient for a user. For example, the user may be occupied with other activities where using his/her hands to perform the button press may not be possible, such as a user may be driving a car.
Other approaches replace button presses with hands-free approaches that activate the speech recognizer using activation words. For example, trigger phrases are used to activate the speech recognizer, which can then decipher a query and provide an appropriate response after the trigger phrase is received. However, the user must always trigger the speech recognizer. Additionally, since the user has triggered the recognizer, errors in the recognition or responses are typically not tolerated by the user.
In all these approaches, a user is deciding when to issue a query or command. The speech recognizer is affirmatively activated and then a response is expected by the user. Because the user is expecting a response, errors in speech recognition may not be tolerated. Also, because the speech recognizer is only listening for content after activation, certain contexts and important points in a conversation will be missed by the speech recognizer.
Additionally, even when a response is output to a user, the response is a generic response. For example, a speech recognizer may perform a web search using keywords that were recognized. This keyword search would be output to any user that is speaking.

Background speech recognition assistant using speaker verification


Hammer drills and similar devices have an ongoing dust and debris problem that is solved by a protector device covering the drill in a main body protector shielding a user from the materials. The protector device has an evacuation region on its underside with multi dimensional adapters for attaching hoses of varying sizes. Additionally, an insertable collapsible accordion cylinder assists in covering the debris falling from different size drills being used. A second embodiment has a circular saw dust protector attachment arranged as two half moons or ¼ moon and ¾ moon having a central cylinder at their respective tops that are to be held together with a mechanical latch.

A hammer drill is known by various other names such as a rotary hammer, roto-drill or hammering drill. This type of drill has a rotary action interacting with a hammering action. The hammering action provides a hammer strike that quickly pulverizes a brittle surface and permits faster drilling with less effort. These drills are typically electric or battery powered, whilst larger units use electro-pneumatic technology to provide sufficient power.
Another type of drill is called a hole saw with a mandrel; it has a central rod with a central circle arranged perpendicularly to the rod; at the edge of this central circle is the main cutting device of the drill. As its name implies, the hole saw uses a circularly arranged set of teeth to cut out a circular shape in a ceiling or other structure. Once opened, these orifices can serve for the hanging of lights or other useful devices.
These type of drills when used on concrete structures or similar surfaces generate a great deal of dust and chips filling the surrounding work area with a cloud of debris. This byproduct of a simple construction procedure can severely impact the workspace environment leading to a laborious cleanup. Additionally, persons or animals nearby his type of drill can inhale this material as it lingers in the air about the drill.
Accordingly, these is a need to overcome the aforementioned deficiencies.


Taking a set of unlabeled images of a collection of objects acquired under different imaging conditions, and decomposing the set into disjoint subsets corresponding to individual objects requires clustering. Appearance-based methods for clustering a set of images of 3-D objects acquired under varying illumination conditions can be based on the concept of illumination cones. A clustering problem is equivalent to finding convex polyhedral cones in the high-dimensional image space. To efficiently determine the conic structures hidden in the image data, the concept of conic affinity can be used which measures the likelihood of a pair of images belonging to the same underlying polyhedral cone. Other algorithms can be based on affinity measure based on image gradient comparisons operating directly on the image gradients by comparing the magnitudes and orientations of the image gradient.

From the photography aficionado type digital cameras to the high-end computer vision systems, digital imaging is a fast growing technology that is becoming an integral part of everyday life. In its most basic definition, a digital image is a computer readable representation of an image of a subject taken by a digital imaging device, e.g. a camera, video camera, or the like. A computer readable representation, or digital image, typically includes a number of pixels arranged in an image file or document according to one of many available graphic formats. For example, some graphic file formats include, without limitation, bitmap, Graphics Interchange Format (GIF), Joint Photographic Experts Group (JPEG) format, and the like. A subject is anything that can be imaged, i.e. photographed, video taped, or the like. In general, a subject may be an object or part thereof, a person or a part thereof, a scenic view, an animal, or the like. An image of a subject typically comprises viewing conditions that, to some extent, make the image unique. In imaging, viewing conditions typically refer to the relative orientation between the camera and the object (i.e., the pose), and the external illumination under which the images are acquired.
Variation in viewing conditions have long been a challenge in the field of image clustering for computer vision. Particularly, clustering of three-dimensional (3-D) images according to the subject represented presents a difficult problem because images of the same subject under different viewing conditions can be drastically different. Conversely, images with similar appearance may originate from two very different subjects. The various viewing conditions can be isolated to present a different problem for clustering purposes. One such problem subset can be the clustering problem for images taken under varying illumination conditions with the subject in fixed pose. This problem is difficult because images of the same subject may look drastically different under different lighting, while different subjects may appear similar under different illumination conditions.
Consider for example the images shown in FIG. 1. There are two natural ways to consider clustering these images: they can be clustered by illumination condition or by identity of the subject. It should be noted that in each such cluster, the shadow formation is more or less the same, and this can be exploited directly by computing some statistics among pixels. Numerous algorithms for estimating lighting direction have been proposed and undoubtedly many of these algorithms can be applied with few modifications to clustering according to lighting. On the other hand, clustering by identity is considerably more difficult when the appearances of a subject class vary dramatically. For example, prior work on face recognition has observed that the appearance variation of the same person under different lighting condition is almost always larger than the appearance variation of different people under the same lighting conditions.
Therefore, it is desirable to provide a system and method that can reliably cluster digital images of subjects taken under various illumination conditions based on the subject's identity.

Clustering appearances of objects under varying illumination conditions


A power factor correcting converter includes a control circuit that modulates on and off intervals of a power switch so that a momentary input current of the converter is directly proportional to both a momentary value of an input voltage of the converter and to a momentary value of a current absorbed by a load coupled to an output of the converter.

This invention applies to the field of control of switching power converters and more particularly to the control of converters that absorb from their input voltage source a current that is directly proportional to the momentary value of voltage.
Converters operating in this fashion are often used to perform what is known as power factor correction.

Method and control circuit for power factor correction


A heat transfer assembly includes a printed circuit board assembly supporting an electronic component assembly including one or more semiconductor chips. A heat sink assembly is adapted to be placed in thermal engagement with the one or more semiconductor chips. Included is a loading assembly for loading the one or more semiconductor chips toward engagement with the heat sink assembly. An encapsulating mechanism is provided that contains a sufficient amount of a thermally conductive medium to transfer heat between a surface of one or more of the semiconductor chips and the heat sink assembly, wherein the thermally conductive medium fills any gaps or space between the one or more semiconductor chips and the heat sink assembly.

The present invention relates in general to the field of heat transfer, and, in particular, to a heat transfer assembly and method that efficiently removes heat from electronic components.
Electronic components, such as microprocessors and integrated circuits, must operate within certain specified temperature ranges to perform efficiently. Excessive heat degrades electronic component performance, reliability, life expectancy, and can even cause failure. Heat sinks are widely used for controlling excessive heat. Typically, heat sinks are formed with fins, pins, or other similar structures to increase the surface area of the heat sink and thereby enhance heat dissipation as air passes over the heat sink. In addition, it is not uncommon for heat sinks to contain high performance structures, such as vapor chambers and/or heat pipes, to enhance further heat transfer. Heat sinks are typically formed of metals, such as copper or aluminum. More recently, graphite-based materials have been used for heat sinks because such materials offer several advantages, such as improved thermal conductivity and reduced weight.
Electronic components are generally packaged using electronic packages (i.e., modules) that include a module substrate to which the electronic component is electronically connected. In some cases, the module includes a cap (i.e., a capped module) which seals the electronic component within the module. In other cases, the module does not include a cap (i.e., a bare-die module) wherein the electronic component directly engages the heat sink.
Bare-die modules are generally preferred over capped modules from a thermal performance perspective. In the case of a capped module, a heat sink is typically attached having a thermal interface gap material existing between a bottom surface of the heat sink and a top surface of the cap, and another thermal interface gap material existing between a bottom surface of the cap and a top surface of the electronic component. In the case of a bare-die module, a heat sink has a thermal interface gap material existing between a bottom surface of the heat sink and a top surface of the electronic component. Bare-die modules typically exhibit better thermal performance than capped modules because bare-die modules eliminate two sources of thermal resistance present in capped modules, i.e., the thermal resistance of the cap and the thermal resistance of the thermal interface gap material between the cap and the electronic component. Accordingly, bare-die modules are typically used to package electronic components, such as semiconductor chips, that require high total power dissipation.
Heat sinks are attached to modules using a variety of attachment mechanisms, such as clamps, bolts, and other hardware. The attachment mechanism typically applies a force that maintains a thermal interface gap, i.e., the thickness of the thermal interface gap material extending between the heat sink and the module. In the case of a capped module, the cap protects the electronic component from physical damage from the applied force. In the case of a bare-die module, however, the applied force is transferred directly through the electronic component itself onto the bare-die module. Consequently, when bare-die modules are used, the attachment mechanism typically applies a compliant force to decrease stresses on the electronic component.
FIG. 1 illustrates an example of a prior art attachment mechanism for attaching a heat sink to a bare-die module. There is illustrated a circuit board assembly 100 that includes a printed circuit board 105, and a bare-die module 110. Bare-die module 110 includes a module substrate 115, an electronic component, such as a semiconductor chip 120, and an electronic connection 125. Semiconductor chip 120 is electrically connected to module substrate 115. Electronic connection 125, which electrically connects printed circuit board 105 to module substrate 115, may be a pin grid array (PGA), a ceramic column grid array (CCGA), a land grid array (LGA), or the like. Semiconductor chip 120 is thermally connected to a heat sink 130 through a thermal interface gap material 135. The thermal interface gap material maybe a layer of a thermally conductive medium, such as thermal paste, grease, oil, or other high thermal conductivity material. Typically, the thermal interface gap material 135 is relatively thin so that it may effectively transfer heat away from the bare-die module 110 and toward heat sink 130. The thickness of thermal interface gap material 135 extending between heat sink 130 and semiconductor chip 120 is referred to as the thermal interface gap.
Heat sink 130 is attached to bare-die module 110 using bolts 140. Bolts 140 pass through thru-holes 131 in heat sink 130 and thru-holes 106 in printed circuit board 105 and are threaded into threaded-holes 146 in a backside bolster 145. Typically, bolts 140 are arranged one at each corner of the electronic component 120, or one on each side of the electronic component 120. Bolts 140 are tightened by threading a threaded portion of bolts 140 into threaded-holes 146 in backside bolster 145. As bolts 140 are tightened, heat sink 130 engages semiconductor chip 120 through thermal interface gap material 135. Additional tightening of bolts 140 causes deflection (bowing) of the printed circuit board 105, which applies a compliant force to bare-die module 110. More particularly, printed circuit board 105 is slightly flexed in a concave-arc fashion with respect to bare-die module 110.
Presently, some computer systems use multiple chip assemblies that require high and stable loading. The multiple chip assemblies have very thin thermal gaps filled with a thermal interface layer to establish thermal engagement with the heat sink. However, due to physical chip height variations, the noted deflections can lead to non-planar thermal interfaces being formed, thereby resulting in possible thermal degradation of the CPU. Moreover, the detrimental effects due to differences in chip height get more pronounced with power cycling loading. During power cycling loading, the chip heat dissipation results in a temperature gradient across the chip, thermal interface layer, and heat sink base. This temperature gradient has thermal transients around the vicinity of the chip, thereby resulting in distortion or relative movement of the heat sink base to the chip. These effects are further compounded when a bare-die solution is used. Consequently, thermal efficiency is compromised. Accordingly, continuing efforts are being made to improve thermal efficiency in such situations.

Method and apparatus for optimizing heat transfer with electronic components

International Business Machines Corporation


Disclosed herein are some examples of analog-to-digital converters (ADCs) that can perform auto-zeroing with amplifying a signal for improvement of a signal-to-noise ratio. The ADCs may produce a first digital code to represent an analog input signal and a second digital code based on a residue from the first digital code, and may combine the first digital code and the second digital code to produce a digital output code to represent the analog input signal. The ADC may utilize a first observation and a second observation of an analog residue value representing the residue to produce the second digital code.

Analog signals and/or values can be produced in various kinds of circuit elements, such as signal generators, sensors, and antennas. However, there can be many instances where having digital signals or values can be beneficial, such as for a processing or storing of the signals or values. To utilize the benefits of having a digital signal or value when an analog signal or value has been produced, analog-to-digital converters (ADCs) have been developed to convert the analog signal or value into a digital signal or value.
A signal may be a time-based sequence of values. A digital value may be represented by a code. A name of a code (for example, CODE1) may refer to a digital value represented by the code. Some (but not all) digital values may be represented by codes using binary-weighted encoding. A resolution of a digital value or code expressed in terms of a number of bits may refer to a binary-weighted encoding, regardless of how it may be encoded.
In many electronics applications, analog input values are converted to digital output values (for example, for further digital processing or storage). For instance, in precision measurement systems, electronics are provided with one or more sensors to make measurements, and these sensors may generate analog values. The analog values may be provided as an input to an ADC to generate digital output values for further processing or storage.
ADCs can be found in many places such as broadband communication systems, automated test equipment, audio systems, vehicles, factory automation systems, etc. ADCs can translate analog electrical values representing real-world phenomena, e.g., light, sound, temperature, flow, or pressure. Designing an ADC is a non-trivial task because each application may have different needs in speed, performance, power, cost and size. As the applications needing ADCs grow, the need for accurate and reliable conversion performance also grows.
Some applications may require precise and accurate conversion of analog values, creating a need for precision ADCs (precision meaning precise and/or accurate). Required specifications for a precision ADC may include low noise and a small and stable offset. A constant-zero offset may be ideal. ADCs and other circuits may be designed aiming for a constant-zero offset, but imperfections of a manufacturing process, mismatch of nominally-identical semiconductor devices, atom-level charge mobility, etc. may cause a circuit's offset to be potentially non-zero and it may drift with respect to parameters such as time, temperature, and/or supply voltage. Auto-zeroing (AZ) circuits may be used in precision ADCs to stabilize (i.e., reduce and/or substantially prevent drift of) a potentially non-zero offset. An offset of an auto-zeroing circuit may be substantially zero (such as less than 100 micro-volts including drift). However, legacy AZ circuits may increase a level of broadband noise, which is detrimental when low noise and low power is also desired. A power consumption of a precision ADC may have to be increased to reduce noise to an acceptable level when an AZ circuit is used. There is a need for low-power ADCs, including a need for low-power, low-offset, and low-noise precision ADCs.
Several types of AZ circuits have been developed. FIG. 1 shows a prior art AZ amplifier circuit 120. AZ amplifier circuit 120 may operate in two phases: phase 1 (labeled ϕ1 in FIG. 1) and phase 2 (labeled ϕ2 in FIG. 1). Phase 1 and phase 2 are non-overlapping in time, and an operation may repeat periodically or non-periodically. Switches 113 and 107 are closed (conductive) during phase 1 and they are otherwise open (non-conductive). Likewise, switches 115p, 115m are closed during phase 2 and they are otherwise open. A voltage-in-voltage-out amplifier circuit 121 has two input terminals 103p, 103m and two output terminals 105p, 105m. In one example, terminals 103m and 105m are connected and share a common potential, such as ground or 0V. In phase 1, input terminals 103p, 103m are shorted by a switch 107, which establishes a nominally zero voltage across input terminals 103p, 103m. Amplifier circuit 121 has a potentially non-zero offset, such as OS=1 mV. An amplified offset may be observed at terminals 105p, 105m when switch 107 is closed during phase 1. For example, if amplifier circuit 121 has a factor of voltage gain, GAIN=200, then an amplified offset GAIN·OS=200·1 mV=200 mV is observed as a voltage between output terminals 105p and 105m. Note that offset OS may be an unwanted artifact of amplifier circuit 121, and that AZ amplifier circuit 120 need not include any circuitry for intentionally providing a non-zero offset OS. Accordingly, FIG. 1 does not (and should not) show a source or any other circuitry for providing or representing the offset OS, which may be (but need not be) nominally zero. An amplified non-zero offset may be observed as a non-zero voltage between terminals 105p, 105m even if the voltage between terminals 103p, 103m is exactly zero.
A capacitor 109 is configured between terminal 105p and a terminal 111p. A switch 113 shorts terminals 111p and 105m during phase 1, whereby an amplified offset may be observed as a voltage across capacitor 109. Switch 113 is opened slightly before switch 107 is opened in a transition from phase 1 to phase 2, whereby the observed amplified offset is sampled on capacitor 109. A voltage VRES (i.e., an analog value) applied to AZ amplifier circuit 120 at its input terminals 101p, 101m is provided to amplifier circuit 121 at terminals 103p, 103m via switches 115p, 115m that are closed during phase 2. If, on the one hand, (VRES>0) then a voltage greater than the amplified offset GAIN·OS is observed between terminals 105p and 105m, and a voltage greater than zero is observed between terminals 111p and 105m. If, on the other hand, (VRES<0) then a voltage less than the amplified offset GAIN·OS is observed between terminals 105p and 105m, and a voltage less than zero is observed between terminals 111p and 105m. Accordingly, a polarity of a voltage VRES applied at an input of AZ amplifier circuit 120 (terminals 101p, 101m) corresponds to a polarity of an amplified voltage GAIN·VRES observed at an output of AZ amplifier circuit 120 (terminals 111p, 105m). When the polarities correspond, an effective offset of AZ amplifier circuit 120 may be zero. An effective offset of AZ amplifier circuit 120 may be zero even if an offset OS of amplifier circuit 121 is non-zero. The described two-phase operation of AZ amplifier circuit 120 may substantially cancel (i.e., reduce to a small value, nominally zero) a potentially non-zero offset of amplifier circuit 121. A circuit, process, or operation that is configured to operate with a plurality of phases and substantially cancel a potentially non-zero offset may be referred to as an "auto-zeroing" circuit, process, or operation. Note that an auto-zeroing operation may require only very little or no knowledge of a circuit's potentially non-zero offset. An AZ circuit (e.g., AZ amplifier circuit 120) provides a nominal operation (e.g., amplification) during only one (e.g., phase 2) of a plurality of phases (e.g., phase 1 and phase 2) of its operation.
AZ amplifier circuit 120 exemplifies that an offset OS may be amplified and observed in one phase. A combination of an input VRES and an offset OS may be amplified and observed in another phase. AZ amplifier circuit 120 combines and outputs a combination of the two observations, whereby a combined contribution from the offset OS may be substantially zero. Specifically, a first observation, GAIN·OS, and a second observation, GAIN·(VRES+OS), are combined such that a contribution from the offset in one observation may be substantially cancelled by an equal-and-opposite (of equal magnitude and of opposite polarity) contribution from the offset in the other observation. For example, a combination of the two observations is GAIN·(VRES+OS)−GAIN·OS=GAIN·VRES. A contribution from the input VRES to the combined output is GAIN·VRES. A contribution from the offset OS to the combined output may be substantially zero, GAIN·(OS−OS)=0. An auto-zeroed offset may be nominally zero. AZ circuits may suppress low-frequency noise modeled as an offset drifting over time.
Successful operation of AZ amplifier circuit 120 in FIG. 1 depends on an observation sampled on capacitor 109 in phase 1 being substantially maintained during a subsequent phase 2. To achieve that, AZ amplifier circuit 120 is coupled to an amplifier (or buffer) circuit 117 configured to draw only very little if any charge from terminal 111p through capacitor 109 during phase 2. An offset of amplifier circuit 117 is suppressed by a factor of gain (such as GAIN=200) provided by AZ amplifier circuit 120 when it is referred to an input VRES. In some applications, amplifier circuit 117 is an auto-zeroing amplifier circuit, for example AZ amplifier circuit 120. In some implementations, capacitor 109 is split in two (not shown) and a first-half capacitor is configured in series with terminal 105p and a second-half capacitor is configured in series with terminal 105m.
FIG. 2 shows another prior art type of AZ amplifier circuit 220. A voltage-in-voltage-out amplifier circuit 221 subject to auto-zeroing has a pair of input terminals 203p and 203m and a pair of output terminals 205p and 205m. It furthermore has an auxiliary input 211 for applying an auxiliary (control) voltage. An effective (auto-zeroed) offset of AZ amplifier circuit 220 is a combination of a potentially non-zero offset of amplifier circuit 221 and an auxiliary voltage applied at input 211 to cancel a contribution from the offset. Amplifier circuit 221 is a 2-stage amplifier circuit that is well-known to persons having ordinary skill in the art (PHOSITA). It comprises an input gm-stage (i.e., a transconductance circuit, not shown) coupled to input terminals 203p and 203m and an output stage (e.g., a transresistance stage, not shown) coupled to output terminals 205p and 205m. An auxiliary gm-stage (not shown) is coupled to input 211 and to the input gm-stage. Currents provided by the input gm-stage and the auxiliary gm-stage are combined, such that a current provided by the auxiliary gm-stage may cancel an offset for the input gm-stage. An auxiliary voltage is sampled and stored on a capacitor 209 coupled to input 211. Capacitor 209 is not directly coupled to output terminals 205p, 205m. A first terminal of capacitor 209 connected to input 211 is substantially floating when a switch 213 is open. Output terminals 205p, 205m of amplifier circuit 221 are also output terminals of AZ amplifier circuit 220. An input impedance of an optional loading circuit 217 may be relatively unimportant, and AZ amplifier circuit 220 may be more versatile in use than AZ amplifier circuit 120 of FIG. 1 may be.
AZ amplifier circuit 220 operates in two phases: phase 1 (labeled ϕ1 in FIG. 2) and phase 2 (labeled ϕ2 in FIG. 2). During phase 1, a switch 207 is closed to apply a zero voltage across terminals 203p and 203m. An amplified combination of a potentially non-zero offset and an auxiliary voltage is observed as a voltage at terminals 205p, 205m, which is connected to a gm-stage (transconductance stage circuit) 223. Switch 213 couples gm-stage 223 to capacitor 209 and input 211 during phase 1. A polarity of the amplified combination nominally determines a polarity of current provided by gm-stage 223, which accordingly may increase or decrease the auxiliary voltage at input 211 during phase 1 when switch 213 is closed. A negative-feedback mode of operation ensures that the auxiliary voltage at input 211 is substantially settled at the end of phase 1 and the amplified combination at terminals 205p, 205m may be substantially zero.
Switch 213 is opened a period of time before switch 207 is opened in a transition from phase 1 to phase 2. That effectively samples the substantially settled auxiliary voltage on capacitor 209 and holds it at input 211 during phase 2. A switch 219 is closed during phase 2 to divert a current that may be provided by gm-stage 223. Alternatively, gm-stage 223 is temporarily turned off to save power during phase 2, and/or it is disconnected from terminals 205p, 205m by switches (not shown). An analog input value VRES is applied to AZ amplifier circuit 220 at input terminals 201p, 201m. The analog input value is provided to amplifier circuit 221 at terminals 203p, 203m via switches 215p, 215m that are closed during phase 2.
An operation of AZ amplifier circuit 220 is as follows. In phase 1, a negative-feedback operation regulates an auxiliary voltage such that an amplified combination of an offset and the auxiliary voltage is substantially zero at or near the end of phase 1 when the auxiliary voltage is sampled on capacitor 209. An amplified contribution from the sampled auxiliary voltage may be substantially equal-and-opposite an amplified contribution from the offset. The sampled auxiliary voltage is a first observation of the amplified offset.
In phase 2, amplifier circuit 221 amplifies a combination of an input VRES, an offset, and the sampled auxiliary voltage. The amplified combination is observed and output at terminals 205p, 205m. A contribution from the offset to the amplified combination may be substantially equal-and-opposite a contribution from the sampled auxiliary voltage to the amplified combination, and the two contributions may substantially cancel each other at terminals 205p, 205m. That is an auto-zeroing operation. Accordingly, the amplified combination observed and output at terminals 205p, 205m is responsive to VRES and substantially not responsive to an offset of amplifier circuit 221. The sampled auxiliary voltage is a first observation of the amplified offset, and it is combined with a second observation of the amplified offset made during phase 2.
Various types of auto-zeroing amplifiers are known in the prior art. A common property is that they operate in a plurality of phases, and that a nominally zero voltage is applied at an input during one of the plurality of phases of operation. Another common property is that observations made during the plurality of phases are combined to substantially cancel a potentially non-zero offset.
An auto-zeroing amplifier may be configured to amplify a residue value in an analog-to-digital converter (ADC) circuit. FIG. 3 shows a block diagram of an ADC 300 comprising a residue amplifier 320. In some examples, residue amplifier 320 is an AZ amplifier circuit 220 shown in FIG. 2. ADC 300 receives an analog voltage VIN(t). A sample-and-hold (S/H) circuit 301 samples VIN(t) at a sampling instant (t=T0) and outputs a held analog value VIN. A first quantizer (ADC1) 303 is configured to receive analog value VIN and derive a first digital value (CODE1) representing VIN. Digital value CODE1 is a relatively low-resolution digital representation of VIN. For example, CODE1 may be a 5-bit digital representation of VIN. ADC 300 derives and processes a residue of VIN with respect to CODE1 as a step of a method to derive a higher resolution and more precise digital representation of VIN. Specifically, a digital-to-analog converter (DAC) 305 derives an analog representation of CODE1, and a difference between VIN and the analog representation of CODE1 is a residue value VRES. The residue value VRES is amplified by residue amplifier 320, and a second quantizer (ADC2) 330 is configured to derive a digital representation CODE2 of the residue value VRES accounting for a factor of gain A provided by residue amplifier 320. A combination of CODE1 and CODE2 is a high-resolution precision representation of VIN.
A degree of precision that can be achieved by ADC 300 may depend substantially on a degree of precision that is achieved by DAC 305 and by residue amplifier 320. For comparison, a degree of precision of ADC1 303 may be relatively much less important, provided CODE2 is an accurate representation of the residue value VRES. A degree of precision needed from ADC2 330 is less than the overall degree of precision provided by ADC 300, provided an absolute value of gain factor A of residue amplifier 320 is larger than 1. An upper limit for gain factor A depends on a resolution and precision of CODE1 representing VIN. For example, a gain factor A=16 is used if CODE1 is of 5-bit resolution and of a precision that will not cause overload/saturation of residue amplifier 320 and/or ADC2 330.
For clarity, ADC1 and/or ADC2 may be referred to as "quantizers" as an alternative to ADCs. PHOSITA recognize that ADC2 330 in FIG. 3 may be implemented as ADC 300 of FIG. 3, in an overall recursive-type structure. A so-called pipelined ADC is a well-known example of an ADC 300 where ADC2 330 is a cascade of several similar stages.
The block diagram of ADC 300 in FIG. 3 represents any one of several types of analog-to-digital converters comprising a residue amplifier 320. For example, ADC 300 may be a so-called hybrid-SAR ADC, where CODE1 is derived at least in part by using a successive-approximation-type algorithm (PHOSITA recognize that SAR ADC stands for "successive-approximation-register analog-to-digital converter". PHOSITA are familiar with the design and operation of SAR ADCs). In another example, CODE1 is derived by a flash-type ADC1 303 configured to receive VIN. In other examples, CODE 1 is provided by a flash or other type of ADC configured to receive VIN(t) and an operation (e.g., an operation to sample VIN(t)) is synchronized with that of S/H circuit 301. In yet other examples, ADC1 303 in FIG. 3 is a SAR quantizer, a hybrid-SAR quantizer, a VCO-based quantizer, a two-step quantizer, a multi-step quantizer, or a pipelined quantizer providing a digital value CODE1 that is a relatively high-resolution representation of VIN (such as CODE1 may be of 10-bit or higher resolution). Accordingly, ADC1 303 in FIG. 3 is a representation of some type of circuit or some type of method to provide a digital representation CODE1 of VIN. The ADC 300 derives an analog residue value VRES as a difference of an analog representation of a digital value CODE1 and an analog value VIN. In one example, a capacitive digital-to-analog converter (CDAC) circuit receives the analog value VIN and the digital value CODE1, and produces the analog residue value VRES based from the analog value VIN and the digital value CODE1. A terminology may be that VRES is a residue of VIN with respect to CODE1, or equivalently (changing polarity) that VRES is a residue of CODE1 with respect to VIN. A magnitude and other properties of residue VRES depend on how CODE1 may be derived to represent VIN, particularly including (but not limited to) a resolution and precision of CODE1.
A degree of precision that can be achieved by ADC 300 depends substantially on a degree of precision that may be achieved by DAC 305 and residue amplifier 320. Some approaches include deriving VIN by sampling a combination of an analog input value VIN(t) and an analog dither value. The approaches may generalize an operation of S/H circuit 301 and DAC 305, which are combined via a capacitive digital-to-analog converter (CDAC) circuit. In another approach, a high-resolution digital value CODE1 is derived that allows for a high factor of gain A of the residue amplifier 320 (if so desired). Accordingly, many variations of ADC circuits may be configured to incorporate a low-offset residue amplifier circuit described herein.
FIG. 4 shows an example ADC 400 that corresponds to the block diagram of FIG. 3. It is a differential ADC 400 receiving an analog input voltage difference VIN(t)=Vp(t)−Vm(t) at input terminals 401p and 401m. During an acquisition phase (labeled ϕ0 in FIG. 4) switches 403p, 403m, 405p, 405m are closed, and the analog input voltage is applied to capacitor arrays 407p, 407m. At a sampling instant (t=T0) at or near the end of the acquisition phase, sampling switches 405p, 405m are opened to isolate a differential charge quantity at nodes 409p, 409m. Input switches 403p, 403m are opened a short delay (such as 200 pico-seconds) after the sampling instant. Capacitor arrays 407p, 407m are a part of a CDAC structure. PHOSITA are familiar with CDAC structures. Capacitor array 407p has a shared terminal connected to terminal 409p and a plurality of N1 terminals connected to input switch 403p (compare to FIG. 2 of U.S. Pat. No. 8,810,443). Accordingly, input switch 403p may be an array of switches, having a shared terminal connected to input terminal 401p, and a plurality of N1 terminals connected to capacitor array 407p. The same may apply for 407m, 409m, 403m, and 401m.
FIG. 4 shows in part a first quantizer ADC1 implemented as a pair of quantizers, ADC1p 411p and ADC1m 411m, configured to individually process each voltage, Vp(t) and Vm(t), applied at the input terminals 401p, 401m (each voltage is observed with respect to a predefined potential, such as ground or 0V). Quantizers 411p and 411m sample Vp(t) and Vm(t) at a sampling instant (t=T0) when sampling switches 405p, 405m are opened. Accordingly, a plus-input digital value CODE1p represents a value Vp(T0) of Vp(t) at the sampling instant, and a minus-input digital value CODE1m represents a value Vm(T0) of Vm(t) at the sampling instant. A plus-to-minus digital value CODE1=CODE1p−CODE1m represents an analog input value VIN=Vp(T0)−Vm(T0) at the sampling instant. In another embodiment, a single differential quantizer ADC1 is configured to provide a digital value CODE1 to represent VIN=Vp(T0)−Vm(T0), without necessarily processing each input Vp(t) and Vm(t) individually.
The derived digital values CODE1p is applied via switches 413p, 415p so that an analog value (e.g., a voltage) at terminal 409p is a residue VRESp of Vp(T0) with respect to CODE1p. Likewise, CODE1m is applied via switches 413m, 415m so that an analog value (e.g., a voltage) at terminal 409m is a residue VRESm of Vm(T0) with respect to CODE1m. Switches 413p, 413m connect individual capacitors in capacitor arrays 407p, 407m to a first/high reference potential VH responsive to individual bits of CODE1p and CODE1m. Likewise, switches 415p, 415m connect individual capacitors in capacitor arrays 407p, 407m to a second/low reference potential VL responsive to individual bits of CODE1p and CODE1m. A capacitor in capacitor array 407p or capacitor array 407m is connected to either VH or VL responsive to a bit of CODE1p or CODE1m. The term capacitive digital-to-analog converter (CDAC) may be used to describe capacitor arrays 407p, 407m and pertinent switches and reference potentials.
Accordingly, an analog value is sampled on a CDAC (e.g., Vp(T0) is sampled on one or more capacitors in capacitor array 407p via switches 403p and 405p); a digital value is applied to a CDAC (e.g., switches 413p, 415p selectively connect individual capacitors of capacitor array 407p to reference potentials VH or VL responsive to CODE1p); and a CDAC provides an analog value that is a residue of a sampled analog value with respect to a digital code (e.g., a potential/voltage at node 409p is a residue VRESp of Vp(T0) with respect to CODE1p).
A residue amplifier 420 is configured to receive a residue value VRES=VRESp−VRESm (e.g., a voltage between nodes 409p and 409m) representing a residue of an analog value VIN=Vp(T0)−Vm(T0) with respect to a digital value CODE1=CODE1p−CODE1m. The residue amplifier 420 provides an amplified residue value A·VRES that is processed by a quantizer circuit ADC2 430. ADC2 430 is configured to provide a digital value CODE2 representing a residue VRES of VIN=Vp(T0)−Vm(T0) with respect to CODE1=CODE1p−CODE1m accounting for a factor of gain A provided by the residue amplifier 420. A digital circuit 440 combines CODE1p, CODE1m, and CODE2 to provide a digital output code DOUT that may be a high-resolution representation of VIN=Vp(T0)−Vm(T0). For example, ADC 400 provides an output code DOUT that is of 20-bit or 24-bit resolution. To achieve a high degree of precision, digital circuit 440 optionally receives and processes calibration information. Calibration information includes a plurality of codes representing capacitance ratios for capacitors in capacitor arrays 407p, 407m. Calibration information is obtained/measured as part of a manufacturing process and it is stored in a memory device (not shown). A degree of precision that can be achieved by ADC 400 is substantially limited by an offset and a level of noise of residue amplifier 420. A legacy AZ residue amplifier (e.g., AZ amplifier circuit 220 of FIG. 2) may provide good offset stability, but at a relatively high/poor noise level. For comparison, a non-auto-zeroing residue amplifier may provide a relatively lower/better noise-and-power operation, but its offset stability may be relatively poor.

Analog-to-digital converter with auto-zeroing residue amplification circuit


A refrigerant cycle is disclosed having a number of compressors operating in tandem and supplying a compressed refrigerant to a refrigerant system. Discharge lines communicate a compressed refrigerant to a central discharge line for receiving flow from all tandem compressors. A control is operational to determine a number of compressors need to be operated or whether some compressors should be shutdown to satisfy load requirements. Shutoff valves are placed on discharge lines outwardly of the shell of the compressors. That can be shutdown during part load operation. These shutoff valves are closed when their associated compressors are stopped to prevent backflow of refrigerant from operating compressors through the shutoff compressor, and into the system suction side. Additionally, high pressure differential across the compressor internal discharge check valve is eliminated and the possibility of compressor flooding through a discharge line is reduced. Thus, compressor/system performance is enhanced and reliability is improved.

This application relates to a shutoff valve placed on a connecting discharge line downstream of a compressor operating in a tandem compressor arrangement.
Refrigerant systems typically include a compressor delivering a compressed refrigerant from a compressor discharge port to a condenser, and then passing the refrigerant from the condenser to an expansion device, an evaporator, and then back to the compressor suction port. The load demand on the refrigerant cycle may vary. At times, there may be a need for a higher system cooling capacity and hence higher compressed refrigerant flow, and at other times, a lower cooling capacity and consequently lower refrigerant flow.
To provide continuous efficient supply of the desired amount of compressed refrigerant, some larger refrigerant systems utilize tandem compressors. In such systems, two compressors may simultaneously deliver a compressed refrigerant to a downstream heat exchanger, such as a condenser. Typically, fluid lines communicate with the discharge ports of the two compressors, and are merged into a single discharge line that sends refrigerant to the condenser. The system suction line is split in similar fashion into individual suction lines connecting to the suction port of each tandem compressor.
A control for such a tandem compressor system will operate one, or both of the compressors depending on system load. In situations where only one of the compressors is operational, the refrigerant can leak from a discharge line to suction line through the shutdown compressor. While the compressors are typically provided with a discharge check valve within the compressor shell, such check valves typically are not tight enough to prevent such leakage. Further, under high pressure differential, such check valves may distort and become even less fluid-tight, or malfunction. Thus, the prior art tandem compressors, even the ones with check valves within the compressor shell can have substantial leakage losses and subsequent system performance degradation.

Tandem compressors with discharge valve on connecting lines


Placing a conductive member between a plasma chamber in a remote plasma reactor and a substrate to shield the substrate from irradiation of undesirable electromagnetic radiation, ions or electrons. The conductive member blocks the electromagnetic radiation, neutralizes ions and absorbs the electrons. Radicals generated in the plasma chambers flows to the substrate despite the placement of the conductive member. In this way, the substrate is exposed to the radicals whereas damages to the substrate due to electromagnetic radiations, ions or electrons are reduced or removed.

1. Field of Art
The present invention relates to a plasma reactor used for treating surface of a substrate or depositing one or more layers of materials on a substrate.
2. Description of the Related Art
Plasma is partially ionized gas consisting of large concentrations of excited atomic, molecular, ionic, and free-radical species. The radicals generated by plasma can be used for various purposes, including (i) chemically or physically modifying the characteristics of a surface of a substrate by exposing the surface to the reactive species or radicals, (ii) performing chemical vapor deposition (CVD) by causing reaction of the reactive species or radicals and source precursor in a vacuum chamber, and (iii) performing atomic layer deposition (ALD) by exposing a substrate adsorbed with source precursor molecules to the reactive species or radicals.
There are two types of plasma reactors: (i) a direct plasma reactor, and (ii) a remote plasma reactor. The direct plasma reactor generates plasma that comes into contact directly with the substrate. The direct plasma reactor may generate energetic particles (e.g., free radicals, electrons and ions) and radiation that directly contact the substrate. Such contact may cause damage to the surface of the substrate and also disassociate source precursor molecules adsorbed in the substrate. Hence, the direct plasma reactor has limited use in fabrication of semiconductor devices or organic light emitting diode (OLED) devices.
A remote plasma device generates plasma at a location remote from the substrate. When generating the plasma, other undesirable irradiation of electrons, ultraviolet ray or ions may also result from the plasma. The substrate may be exposed to such irradiation and cause damage to the substrate or make undesirable changes to the properties of the substrate.

Plasma reactor with conductive member in reaction chamber for shielding substrate from undesirable irradiation


A technique for providing a wish list is disclosed. The technique comprises displaying the wish list, modifying the wish list, and sending substantially in real-time information associated with the wish list.

Instant messaging has become one of the most popular applications on the Internet. Instant messaging programs generally allow users to send and receive messages. The messages are typically generated and displayed by an instant messaging application on each end and an instant messaging server may perform various functions to facilitate the transfer of messages for communication or conversation.
Software intended for implementing an instruction set in an instant messaging environment may be generally referred to as an instant messenger (IM) application. Existing IM applications typically allow limited data exchanges such as text messages. It would be desirable if the users could share more information about themselves via IM applications in an interactive way. It would also be useful if the sharing of information can be provided via a user interface that is easy to use.

Method and system for sharing information in an instant messaging environment


Methods and apparatuses are described to determine subsets of vector signaling codes capable of detection by smaller sets of comparators than required to detect the full code. The resulting lower receiver complexity allows systems utilizing such subset codes to be less complex and require less power.

Communication of information as signals encoded on groups of wires is known, with larger groups allowing use of a larger code space and thus permitting more efficient communication of information. However, the number of differential comparators required to receive such group-encoded signals grows on the order of n2, where n is the size of the group, severely impacting the complexity and power consumption of practical embodiments having more than a few inputs.

Vector signaling with reduced receiver complexity


A method of acoustically attenuating noises of structure-borne origin in an article of manufacture by installing a laminated window having a glass sheet and an intermediate film, where the film has a loss factor tan δ greater than 0.6 and a shear modulus G′ smaller than 2×107 N/m2 in a temperature range between 10 and 60° C. and in a frequency range between 50 and 10,000 Hz.

1. Field of the Invention
The present invention relates to a window for vehicles, particularly automobile vehicles, having improved acoustic insulation properties, especially with respect to noise of structure-borne origin.
2. Discussion of the Background
Soundproofing windows are used not only for windows in buildings but also to an increasing extent in automobiles. Although soundproofing windows for buildings can be relatively thick, laminated windows used for automobile construction usually have thicknesses not exceeding about 6 mm. Consequently it is advisable to use, as an intermediate layer between the two sheets of window glass, a viscoelastic polymer that imparts a highly effective anti-noise effect even in relatively thin layers. In addition, the polymer must also satisfy, over the long term (meaning for the entire life of the vehicle) all conditions imposed on polymers used in automobile windows. These conditions include in particular low cloudiness, high transparency and good ultraviolet resistance. In addition, these polymers must ensure high-quality and durable assembly with the adjacent layers and must retain their good noise-damping properties even at high and low temperatures. Finally, the anti-noise layers must not impair the safety-glass properties of the window. Acrylic viscoelastic polymers have proved particularly appropriate as antinoise layers.
EP 0 532 478 A2 teaches a soundproofing laminated window that is also suitable as an automobile window and that comprises an intermediate layer of viscoelastic acrylic polymer. In the case of this known laminated window, the intermediate layer separating the two glass sheets is formed by a polymerizable monomeric composition comprising 5 to 50 weight % of an aliphatic polyurethane and 15 to 85 weight % of a photopolymerizable mixture of different acrylic monomers and common polymerization additives. The mixture of monomers is admitted into the space separating the two glass sheets, and polymerization by ultraviolet radiation is initiated. This known soundproofing laminated window is not suitable for series production, however, because its process of production (polymerization of the mixture of monomers introduced between the glass sheets) is relatively expensive.
In the case of the industrial process for production of laminated windows, assembly of the two glass sheets with a prefabricated polymer film is generally performed at elevated temperature and under pressure. A process of this type intended for production of laminated windows having good noise-damping properties is known from EP 0 457 190 A1. In the case of this known process, a prefabricated polymer film having a high noise-damping coefficient and comprising at least two layers, one of which is made from a first specified polyvinyl acetal and plasticizer and the other of a second specified polyvinyl acetal and plasticizer.
Viscoelastic acrylic polymers with good noise-damping properties are also known in the form of thin films. These anti-noise films can be used for production of laminated windows by interposing them between two thermoplastic films comprising in particular polyvinylbutyral and bonding them to these films as well as to two external glass sheets by the standard process for production of laminated windows by assembly at elevated temperature and under pressure. Soundproofing windows of this type have a good noise-damping coefficient, but it has been found that in the course of time the acrylic polymer becomes cloudy and the noise-damping properties deteriorate, with the result that the laminated window thereby becomes useless.
On the other hand, among all the qualities contributing to comfort in modem transportation means such as trains and automobiles, silence is becoming the determining factor. In fact, the other sources of discomfort stemming from mechanical, thermal, visibility, and other considerations have been gradually mastered. Improvement of acoustic comfort presents new difficulties, however; noises of aerodynamic origin, in other words noises created by friction between the air and the moving vehicle, have been treated successfully, at least in part, at their source, or in other words, to economize on energy, the shapes have been modified, penetration into the air has been improved, and turbulence effects, which themselves are noise sources, have been reduced. Among the vehicle walls that separate the source of external aerodynamic noise from the inside compartment in which the passenger is situated, windows are obviously the most difficult to treat. Pasty or fibrous absorbing materials intended for opaque walls cannot be used and, for practical or weight reasons, the thicknesses cannot be increased. European Patent EP B1 0 387 148 teaches windows that achieve good insulation from noise of aerodynamic origin without excessive increase in their weight and/or thicknesses. The patent thus teaches a laminated window in which the intermediate layer has a flexural damping coefficient of ν=Δf/fc larger than 0.15, the measurement being performed by shock excitation of a laminated bar of 9 cm length and 3 cm width made of a laminated glass in which the resin is located between two glass members each 4 mm thick, and by measuring fc, the resonance frequency of the first mode, and Δf, the peak width at amplitude A/√{square root over (2)}, where A is the maximum amplitude at frequency fc, such that its acoustic attenuation index does not differ for any of the frequencies higher than 800 Hz by more than 5 dB from a reference index, which increases by 9 dB per octave up to 2000 Hz and by 3 dB per octave at higher frequencies. In addition, the standard deviation a of the differences of its acoustic attenuation index relative to the reference index is always smaller than 4 dB. The thicknesses of the two glass members can be identical and equal to 2.2 mm. This patent therefore proposes a general solution to the problem of acoustic insulation of the aerodynamic noises of a vehicle.
However, the noises themselves such as engine noises, bearing noises or suspension noises must be treated at the same time. These noises have already been treated at their origin or to some extent during their propagation, whether airborne (especially absorbing lining) or structure-borne (joints of elastomer, for example). For windows, European Patent EP B1 0 100 701 teaches windows that achieve good soundproofing of highway noises, or in other words good insulation of noises during their airborne propagation.
One of the windows according to this patent comprises at least one laminated window, and the resin of the laminated window is such that a bar of 9 cm length and 3 cm width made of a laminated glass comprising two glass sheets of 4 mm thickness joined together by a 2 mm layer of this resin has a critical frequency that differs by at most 35% from that of a glass bar having the same length, the same width and a thickness of 4 mm. The windows according to this patent have an excellent acoustic attenuation index for highway traffic.
In contrast, the treatment of windows to combat noises of structure-borne origin, meaning noises transmitted through solids, is more difficult to achieve. In fact, it turns out that the use of joints is still insufficient to prevent transmission of noise by window vibration. In this connection, it has actually been observed that, at certain engine speeds, perceptible buzzing is felt by the passenger, thus causing a source of discomfort. In fact, the engine rotation leads to the development of vibrations which are transmitted, for example, to the car body and then by chain effect to the windows. It is known that the energy acquired by an object subjected to a shock causes a vibration phenomenon, and that, immediately after the shock, once the object has become free again, it vibrates in its natural mode. A vibrational frequency is associated with each mode. The vibrational amplitude depends on the initial excitation, or in other words on the spectral component of the shock (amplitude of the shock at the frequency under study) and of the impact zone of the shock, the magnitude of the modal deformation depending on whether the shock occurred at a neutral point or vibration node.
The following conditions must be met for a natural mode to be excited:    (1) the deformation caused at the point of impact is not situated at a vibration node of the mode,    (2) the energy spectrum of the shock has a component at the resonance frequency of the mode.
This second condition is almost always met, because a very brief shock has a practically uniform energy spectrum.
The first condition is also met and, for a bar free at its ends, for example, it is sufficient to tap one of the ends to excite all modes.
In the application in question, structure-borne excitation is peripheral and the inventors have demonstrated that, at certain engine vibration frequencies, in other words at certain engine speeds, the windows and the passenger compartment of the vehicle each have a vibration mode, the coupling of which amplifies the window buzzing caused by radiation of noises originating in this case from the engine. Of course, the engine speed causing these phenomena is particular to each type of vehicle, and therefore cannot be generalized to a single value.

This patent is subject to a terminal disclaimer.

Soundproofing laminated window for vehicles


The present invention relates to improvements in office panelling systems and the distribution of wires therethrough. A specialty lay-in wire is stackable above other panels and has an open channel for receiving wires, cables and the like without threading through the panels.

A number of systems have been designed for allowing subdividing of office space and the convenient capability to provide power and communication capability at work stations.
One such system is shown in our U.S. Pat. No. 4,535,577 where power is provided at desk height by means of an access door with the panel including an electrical power conduit or passageway through the panel, preferably directly below the access door. Because communication cables are not particularly compatible with power cables, a separate communication passageway is provided therebelow.
Other arrangements have provided an access arrangement at the base of the panel into which the cable feeds can be placed. A further system provides a beam type arrangement at desk height and this beam is capable of receiving electrical power and communication cables.
All of these systems can be installed to satisfactorily provide power to a work station and to distribute communication cables to the various work stations. With the advances made in technology, it is now often desirable or necessary to go back to an existing panelling system and install communication cables and the like. In many cases, these will be low voltage cables which do not require an electrical conduit, or if they are electrical power cables, they can be shielded cables, and a difficulty arises in threading of the cables through various ports in the office panels. Some panels include passageways at the lower edge of the panel which are open to the side, however, in these cases, other equipment such as desks, tables, machinery, etc. may be in front of the panel, rendering access to this lower conduit difficult. Even access above desk height to a passageway may be difficult due to machinery, etc. on the working surfaces. Any arrangement requiring threading of the cables through the system is quite labour intensive and normally requires direct access to the interior of the panel.
There remains a need to provide a system and method for allowing the retrofit of a cabling system with communication cables and the like in a convenient manner.


Implants include fixation features which slidingly receive fixation elements. The fixation features may be negative or positive features, such as undercut channels or posts. Examples include unicompartmental tibial trays having a ridge protruding from the bone-facing side, an undercut channel formed within the ridge. Instruments are disclosed for preparing a ridge-receiving feature in bone. Implants and fixation elements are configured for implantation without penetrating a cortical wall of a bone. Instruments and surgical methods are disclosed.

Arthroplasty procedures seek to replace a natural joint that has deteriorated in its functionality. Joint resurfacing typically involves removal of at least a portion of a natural articular surface of a bone in order to replace the removed tissue with a prosthesis having an articular surface that replicates at least the removed portion of the natural articular surface. Joint replacement may involve more extensive bone removal and subsequent replacement with a more substantial prosthesis. In this disclosure, remarks about resurfacing are to be considered equally relevant to replacement, and vice versa.
Arthroplasty procedures may involve one or more articular surfaces of a joint. In the knee, for example, the medial femoral condyle, the lateral femoral condyle, the medial tibial condyle, the lateral tibial condyle, the trochlear groove, and/or the patella may be resurfaced or replaced. A procedure may be described as unicondylar if one condyle of the joint is treated, such as the medial tibial condyle. Bicondylar procedures may treat two condyles of a bone, such as the medial and lateral tibial condyles. A procedure may be described as unicompartmental if one compartment of the joint is treated, such as the medial compartment of the knee. Bicompartmental procedures may treat two compartments, such as the medial and lateral compartments of the knee. A procedure may be described as a total joint procedure if most or all opposing articular surfaces of the joint are resurfaced or replaced. A procedure may be described as a hemiarthroplasty procedure if the prosthetic component articulates against an opposing natural articular surface, such as the prosthetic medial tibial component articulating against the natural medial femoral condyle.


A discharge system for a destructive distillation apparatus wherein the discharge solids act as plug to avoid the unwanted flow of product gas or ambient air therethrough while effectively discharging finely divided, disperse solids material from a continuously operating distillation apparatus. The use of a positive displacement two-stage auger having close clearance between the auger and auger cylinder wall, combined with an open section within the auger cylinder where a sealing material plug forms, results in improved sealing of the inventive system from unwanted transfer of gases. The hot, disperse, and finely divided solids exiting a distillation apparatus, such as carbon black formed from the distillation of automobile tire chips, is effective in the formation of a seal plug. The solid material sealing plug feature of the present invention is primarily intended as an additional sealing feature useful in conjunction with conventional drop or lock hoppers, but in some circumstances the use of these additional mechanical systems can be eliminated when using the sealing plug technology of the present invention. Also, the provision of inert gas systems as part of the discharge system may be eliminated by the employment of the inventive sealing plug system. The provision of a sealing plug section within the auger conveyor apparatus, along with the provision of small clearances between the outer edge of the auger flight and the auger cylindrical casing, allows the continuous operation of the distillation system without unwanted passage of ambient air into the system, or the passage of distillation product gases through the discharge system, and inhibits the passage of gas surges from the distillation apparatus through the auger conveyor to the solids disposition area.

1. Field of the Invention
The present invention relates to destructive distillation apparatus. More particularly, the present invention relates to discharge systems for apparatus useful in the destructive distillation of waste automobile tires.
2. Discussion of the Prior Art
In the destructive distillation of carbonaceous materials, such as bulk chips of used automobile tires, the finely divided, disperse solids product or residue must be removed from the distillation apparatus. In the case of a batch still the removal of solids material is laborious and time consuming and results in significant downtime for the still. A continuously operating still is clearly desirable to carry out the destructive distillation process in an efficient manner with minimum labor. The lack of an effective system for the safe removal of hot solids material from a continuous destructive distillation apparatus has remained a substantial impediment to the use of continuous stills due to the difficulties involved in handling a continuous stream of finely divided, disperse solids product while preventing either the flow of distillation product gas or vapors out of the system with the carbonaceous solids, which can result in a fire, once the materials reach the outside atmosphere, or the flow of atmospheric air back into the still resulting in fires and explosions. Explosions result in equipment damage and process downtime.
Various systems have been employed in prior discharge systems to avoid potential explosions, including inert gas generators to blanket the discharge system with an inert gas such as combustion gas or nitrogen, and the use of lock hoppers or drop hoppers to isolate the discharge system from ambient air. The provision of inert gas generators in the system adds cost and complexity, and they are subject to failure, resulting in explosion hazards. Lock hoppers or drop hoppers, which provide an air lock between sequentially operated flap valves or rotating vane valves to provide for removal of disperse solids, are less than totally effective in excluding ambient air from the system and are ineffective in preventing the exit of product gases from the distillation process. Rotating vane valves are subject to excessive wear in the hot solids environment contemplated by the invention and fail to effect an adequate seal. Material buildup on flaps or gates results in unacceptable leakage of air and product gases.
The above-described drawbacks of prior art discharge systems have been overcome by the discharge system of the present invention wherein the discharge solids act as a plug seal to avoid the unwanted flow of product gas or ambient air therethrough while effectively discharging finely divided, disperse solids material from a continuously operating distillation apparatus. The use of positive displacement augers having close clearance between the auger and auger cylinder wall, combined with an open section within the auger cylinder where a material plug forms, results in improved sealing of the inventive system from unwanted transfer of gases.
The formation of a solids material plug for sealing in feeding systems is employed by Taylor (U.S. Pat. No. 4,225,392) for gasifier apparatus. However, it has not been previously recognized that the hot, disperse, and finely divided solids exiting a distillation apparatus, such as carbon black formed from the distillation of automobile tire chips, would be effective in the formation of a sealing plug. Although the solid material sealing plug feature of the present invention is primarily intended as an additional sealing feature useful in conjunction with conventional drop or lock hoppers, it is envisioned that in some circumstances the use of these additional mechanical systems could be eliminated when using the sealing plug technology of the present invention. Also, the provision of inert gas systems as part of the discharge system may be eliminated by the employment of the inventive sealing plug system.
It also is generally known to use inclined auger conveyors in combination with valved lock hoppers in a solids discharge system for a retort or still, as shown, for example, by Everman et al. (U.S. Pat. No. 4,690,732. However, the improvements of the present invention, i.e., the provision of a sealing plug section within the auger conveyor apparatus, along with the provision of small clearances between the outer edge of the auger flight and the auger cylindrical casing, allows the continuous operation of the distillation system without unwanted passage of ambient air into the system, or the passage of distillation product gasses through the discharge system, and inhibiting the passage of gas surges from the distillation apparatus through the auger conveyor to the solids disposition area.

Plug seal discharge system for distillation apparatus


A system for and a method of monitoring a plurality of transceivers is disclosed. In one embodiment the method includes enabling one transceiver of the plurality of transceivers. The method also includes disabling all other transceivers of the plurality of transceivers. A transmit coil emits a high frequency electromagnetic field, the one transceiver transmitting a signal in response to the field of the transmit coil. At least one of a plurality of reader coils receives the signal transmitted by the one transceiver, the plurality of reader coils being suitably arranged in the vicinity of the area to be monitored. An evaluator determines a position of the one transceiver from the signal received from the one transceiver by the at least one of the plurality of reader coils.

The invention relates to a system for and a method of monitoring a plurality of transceivers located in an area, e.g. a patch panel, to be monitored.
Data networks serve, inter alia, to provide data links to a larger number of computers, e.g. PCs or work stations, etc., or the staff sitting there, i.e. the users of the data network. The users at the work stations are thus provided with individual services, e.g. with data services or also telecommunication services. In order to achieve this, the data networks have central distributor points, mostly distributor cabinets. Patch panels are provided in the distributor points. These patch panels have ports, i.e. connections. From the ports of these patch panels data cables route data links to the work stations, e.g. in a star pattern.
There are also active devices located in the distributor cabinets or distributor points besides the patch panels. These active devices serve to distribute the data, telephone signals or other applications.
The connection of e.g. the active devices to the patch panels is achieved with patch cables.
These patch cables have a plug at each end. This plug can be inserted into a port or connection on a patch panel. The patch cables are e.g. 8-wired, flexible and e.g. about 0.5 m to 5 m long. In the case of copper cables, the plugs are generally so-called RJ45 plugs; further, optical fibers have been ready-made with various plugs.
To now supply a PC/work station with the desired services or to make these services available thereto, the active device must be connected accordingly to the corresponding port on the patch panel. If, for example, a user needs a telephone connection as well as a data link, then the telephone system and a data switch system are made available for use by connecting the corresponding ports to the active device.
In the case of changes to services, relocations, transfers or other reorganization measures, it may become necessary to make changes to these connections at the distributors. In this case, "patch rearrangement" must be conducted. Thus, patch cables must be re-plugged in keeping with the services required from now on.
A series of problems arise as a result of this. A plurality of patch cables cover the individual patch panels and also become entwined with one another. Connections that are no longer required still remain patched in some instances. Thus, the clarity of overview in the case of medium and large installations necessarily decreases drastically in some cases. These problems result in errors and time losses in conducting re-patching operations. This in turn leads to an increase in work time for the responsible administrator, as well as for the users, until the services are truly available by reworking. The possibility of damages to the devices or even the completely unintended outage of services as a result of incorrect patching should not be excluded.
Arrangements for monitoring patch panels at distributor points in data networks are proposed in, for example, U.S. Pat. No. 6,784,802, DE 102 44 304 B3, and DE 10 2004 052 502 A1.
U.S. Pat. No. 6,784,802 provides a system and a method for monitoring connectivity in a cable system including radio frequency identification (RFID) transceivers on cable ends and RFID sensors at connection points. The RFID sensors are connected to a central monitoring system. Presence of a particular cable end at a particular connection point is detected and recorded by the central monitoring system.
DE 102 44 304 B3 relates to an arrangement for monitoring patch panels, the arrangement including patch cables which can be inserted into the connections in the patch panels by means of a plug. Each plug is fitted with a transponder. Readers with reader spools are also provided. Each connection attachment in a patch panel is fitted with a reader spool or with a reader.
DE 10 2004 052 502 A1 describes an arrangement for monitoring patch fields, the arrangement including patch cables which can be plugged by means of plugs into connectors in the patch fields. Each of the two plugs of each cable is provided with a transponder. A device is arranged before or in the proximity of one of the patch fields with its connectors. The device is equipped with readers and reader coils. The readers are in data communication with an evaluation unit. The device comprises a plurality of reader coils, the number of which exceeds the number of connectors in the patch field. The reader coils can be independently driven.
Thus, known systems or methods only check if one of a plurality of predetermined positions, i.e. possible connection positions, is occupied by a respective plug having a transceiver. With increasing dimension of patch panels it could be desirable, however, to determine the position of the particular connector/plug independent from any predetermined connector positions. In particular, it may be desirable to determine a position of a transceiver of a plurality of transceivers, independent from the arrangement and use of the transceivers. For these or other reasons, there is a need for the present invention.

System and method for monitoring a plurality of transceivers


This invention relates to the use of a nuclear quadrupole resonance detection system for detecting contraband, wherein the detection system comprises a container with a detection panel and at least one coil for exciting and detecting the nuclear quadrupole resonance frequencies of a contraband source placed near an outer side of the detection panel.

The use of nuclear quadrupole resonance (NQR) as a means of detecting explosives and other contraband has been recognized for some time—see e.g. T. Hirshfield et al, J. Molec. Struct. 58, 63 (1980); A. N. Garroway et al, Proc. SPIE 2092, 318 (1993); and A. N. Garroway et al, IEEE Trans. on Geoscience and Remote Sensing, 39, pp. 1108–1118 (2001). NQR provides some distinct advantages over other detection methods. NQR requires no external magnet such as required by nuclear magnetic resonance. NQR is sensitive to the compounds of interest, i.e. there is a specificity of the NQR frequencies.
One technique for measuring NQR in a sample is to place the sample within a solenoid coil that surrounds the sample. The coil provides a radio frequency (RF) magnetic field that excites the quadrupole nuclei in the sample and results in their producing their characteristic resonance signals. This is the typical apparatus configuration that might be used for scanning mail, baggage or luggage. There is also need for an NQR detector that permits detection of NQR signals from a source outside the detector, e.g. a wand detector, that could be passed over persons or containers as is done with existing metal detectors. Problems associated with such a detector using conventional systems are the decrease in detectability with distance from the detector coil and the associated equipment needed to operate the system.
An NQR detection system can have one or more coils that both transmit and receive, or it can have coils that solely transmit or solely receive coil. The transmit, or transmit and receive, coil of the NQR detection system provides a radio frequency (RF) magnetic field that excites the quadrupole nuclei in the sample and results in their producing their characteristic resonance signals that the receive, or transmit and receive, coil detects. The NQR signals have low intensity and short duration. The transmit, receive, or transmit and receive coil is preferably tunable and has a high quality factor (Q). After the RF signal is transmitted, the transmit, receive, or transmit and receive coil will typically experience ringing and it must have a rapid recovery time in order for the receive or transmit and receive coil to be able to detect the low intensity NQR signal. One method of accomplishing this is to use a Q-damping circuit that is activated to provide a rapid recovery.
An object of the present invention is to provide a NQR detector that permits detection of NQR signals from a source outside the detector.

Detection of contraband using nuclear quadrupole resonance


A broadband antenna includes a radiation part (10) for radiating and receiving electromagnetic signals, a feed portion (30) for feeding the electromagnetic signals, and a pair of ground planes (40) respectively disposed on sides of the feed portion. The radiation part comprises an annular first radiation segment (12) and an annular second radiation segment (14) being inscribed within a space defined by the annular shape of the first radiation segment. The feed portion is electrically connected to the radiation part.

1. Field of the Invention
The present invention relates to an antenna, and particularly to a broadband antenna.
2. Description of Related Art
Nowadays, main transmitting modes of wireless local area networks (WLAN) comprise IEEE802.11a, IEEE802.11b, and IEEE802.11g. In addition, with development of wireless communication technology, IEEE802.11n, as a new generation transmitting mode for WLANs, is destined to be compatible with the current transmitting modes for WLANs. That is, it is destined that the IEEE802.11n will be able to operate in both the 2.4˜2.5 GHz band of IEEE802.11b and IEEE802.11g, and the 4.9˜5.85 GHz band of IEEE802.11a. Therefore, an antenna that can operate in both the 2.4˜2.5 GHz and 4.9˜5.85 GHz bands is needed.
Therefore, a heretofore unaddressed need exists in the industry to overcome the aforementioned deficiencies and inadequacies.

Hong Fu Jin Precision Industry (ShenZhen) Co., Ltd.


An integrated circuit includes a digital bus providing a first portion of less significant signals, and a second portion of more significant signals. A digital-to-charge converter connected to the digital bus includes circuitry to convert the less significant portion of the signals to a first charge, and to convert the more significant portion of the signals to a second charge. A charge-to-voltage converter connected to the digital-to-charge converter includes circuitry to convert the first charge to an intermediate voltage. A voltage-to-charge converter connected to the charge-to-voltage converter converts the intermediate voltage to a third charge. A charge-summer connected to the digital-to-charge converter and the voltage-to-charge converter combines the second charge with the third charge to produce a combined charge. The charge-to-voltage converter also is connected to the charge-summer to convert the combined charge to an analog output voltage.

Digital systems often require digital-to-analog (D/A) converters and analog-to-digital (A/D) converters to communicate with analog components. For example, the speed of a DC motor may be controlled by an analog voltage level or current. Previous patents related to D/A converters include U.S. Pat. Nos. 3,967,272 to Sandford, Jr.; 4,410,879 to Gumm; 4,584,568 to Zomorrodi; 4,616,212 to Law; 4,618,852 to Kelley; 4,665,380 to ; 4,667,179 to Law; 4,973,979 to Ikeda; 4,998,108 to Ginthner; and 5,489,904 to Hadidi. Articles related to D/A converters include "All-MOS charge Redistribution Analog-to-Digital Conversion Techniques--Part 1" by McCreary, James L. and Gray, Paul R. in IEEE Journal of Solid State Circuits, vol. Sc-10, pp. 371-79, Dec 1975; and "Integrated PCM Codec" by Ohri, Kul B. and Callahan, Michael J. in IEEE Journal of Solid-State Circuits, vol. SC-14, pp. 36-46, Feb. 1979. The above citations are all incorporated herein in whole by reference.
Herein, voltage is abbreviated V, charge is abbreviated Q, current is abbreviated C, digital is abbreviated D, and analog is abbreviated A. Other abbreviations will be introduced below in the description to reduce unnecessary repetition.

International Business Machines Corporation


A fishing rod has a seat base including a fixed hood formed integral therewith for engaging a forward leg of a fishing reel, and a movable hood mounted in the seat base to be movable axially thereof for engaging a rearward leg of the fishing reel. The seat base defines an opening edge of a space for accommodating the movable hood. This opening edge is inclined, in side view, with respect to an axis of the fishing rod. A rotatable adjusting element is mounted on the seat base for adjusting position of the movable hood axially of the fishing rod. A slide contact element is disposed at an end of the rotatable adjusting element remote from the movable hood for limiting movement of the rotatable adjusting element axially of the fishing rod 2. A fishing rod as claimed in claim 1, wherein said seat base includes a rotatable adjusting element relatively rotatably mounted thereon for adjusting position of said movable hood axially of the fishing rod.

1. Field of the Invention
This invention relates to fishing rods, and more particularly to a fishing rod having a reel seat including a fixed hood securely mounted on a rod stock and a movable hood movably axially of the rod stock for supporting a reel.
2. Description of the Related Art
A known example of such fishing rods is disclosed in Japanese Utility Model Publication Kokai No. 1989-168166. In this example, the fishing rod includes a turn control element slidable with a movable hood, and defines a threaded portion between the turn control element and a boss fixed peripherally of the rod, the movable hood is mounted on the boss to be axially movable but not rotatable relative to the rod, the movable hood being moved by screw feed of the turn control element.
According to the above known construction, a certain stepped portion or a difference in level inevitably is formed between the movable hood and boss.
In the case of a lure rod, the angler usually holds the fishing line and rod in the same hand, gripping the reel seat, before throwing the line in order to prevent loosening of the line wound on the reel. This action is frequently taken.
However, the stepped portion between the movable hood and boss in unpleasant to the touch when such a gripping operation is performed. Thus, there is room for improvement.


In a process for converting methane to aromatic hydrocarbons, a feed containing methane is contacted with a dehydrocyclization catalyst in a reaction zone under conditions including a first maximum temperature effective to convert the methane to aromatic hydrocarbons and generate coke on the catalyst. A portion of the coked catalyst is transferred from the reaction zone to a separate regeneration zone, where the catalyst portion is contacted with a regeneration gas under conditions including a second maximum temperature less than or equal to the first maximum temperature and effective to at least partially remove coke from the catalyst portion. Before being returned to the reaction zone, the regenerated catalyst portion is contacted with a carburizing gas in a catalyst treatment zone separate from the reaction zone at a third maximum temperature less than the first maximum temperature.

Aromatic hydrocarbons, particularly benzene, toluene, ethylbenzene and xylenes, are important commodity chemicals in the petrochemical industry. Currently, aromatics are most frequently produced from petroleum-based feedstocks by a variety of processes, including catalytic reforming and catalytic cracking. However, as the world supplies of petroleum feedstocks decrease, there is a growing need to find alternative sources of aromatic hydrocarbons.
One possible alternative source of aromatic hydrocarbons is methane, which is the major constituent of natural gas and biogas. World reserves of natural gas are constantly being upgraded and more natural gas is currently being discovered than oil. Because of the problems associated with transportation of large volumes of natural gas, most of the natural gas produced along with oil, particularly at remote places, is flared and wasted. Hence the conversion of alkanes contained in natural gas directly to higher hydrocarbons, such as aromatics, is an attractive method of upgrading natural gas, providing the attendant technical difficulties can be overcome.
A large majority of the processes currently proposed for converting methane to liquid hydrocarbons involve initial conversion of the methane to synthesis gas, a blend of H2 and CO. However, production of synthesis gas is capital and energy intensive and hence routes that do not require synthesis gas generation are preferred.
A number of alternative processes have been proposed for directly converting methane to higher hydrocarbons. One such process involves catalytic oxidative coupling of methane to olefins followed by the catalytic conversion of the olefins to liquid hydrocarbons, including aromatic hydrocarbons. For example, U.S. Pat. No. 5,336,825 discloses a two-step process for the oxidative conversion of methane to gasoline range hydrocarbons comprising aromatic hydrocarbons. In the first step, methane is converted to ethylene and minor amounts of C3 and C4 olefins in the presence of free oxygen using a rare earth metal promoted alkaline earth metal oxide catalyst at a temperature between 500° C. and 1000° C. The ethylene and higher olefins formed in the first step are then converted to gasoline range liquid hydrocarbons over an acidic solid catalyst containing a high silica pentasil zeolite.
However, oxidative coupling methods suffer from the problems that they involve highly exothermic and potentially hazardous methane combustion reactions and they generate large quantities of environmentally sensitive carbon oxides.
A potentially attractive route for upgrading methane directly into higher hydrocarbons, particularly ethylene, benzene and naphthalene, is dehydroaromatization or reductive coupling. This process typically involves contacting the methane with a catalyst comprising a metal, such as rhenium, tungsten or molybdenum, supported on a zeolite, such as ZSM-5, at high temperature, such as 600° C. to 1000° C. Frequently, the catalytically active species of the metal is the zero valent elemental form or a carbide or oxycarbide.
For example, U.S. Pat. No. 4,727,206 discloses a process for producing liquids rich in aromatic hydrocarbons by contacting methane at a temperature between 600° C. and 800° C. in the absence of oxygen with a catalyst composition comprising an aluminosilicate having a silica to alumina molar ratio of at least 5:1, said aluminosilicate being loaded with (i) gallium or a compound thereof and (ii) a metal or a compound thereof from Group VIIB of the Periodic Table.
In addition, U.S. Pat. No. 5,026,937 discloses a process for the aromatization of methane which comprises the steps of passing a feed stream, which comprises over 0.5 mole % hydrogen and 50 mole % methane, into a reaction zone having at least one bed of solid catalyst comprising ZSM-5, gallium and phosphorus-containing alumina at conversion conditions which include a temperature of 550° C. to 750° C., a pressure less than 10 atmospheres absolute (1000 kPaa) and a gas hourly space velocity of 400 to 7,500 hr−1.
Moreover, U.S. Pat. Nos. 6,239,057 and 6,426,442 disclose a process for producing higher carbon number hydrocarbons, e.g., benzene, from low carbon number hydrocarbons, such as methane, by contacting the latter with a catalyst comprising a porous support, such as ZSM-5, which has dispersed thereon rhenium and a promoter metal such as iron, cobalt, vanadium, manganese, molybdenum, tungsten or a mixture thereof. After impregnation of the support with the rhenium and promoter metal, the catalyst is activated by treatment with hydrogen and/or methane at a temperature of about 100° C. to about 800° C. for a time of about 0.5 hr. to about 100 hr. The addition of CO or CO2 to the methane feed is said to increase the yield of benzene and the stability of the catalyst.
However, the successful application of reductive coupling to produce aromatics on a commercial scale requires the solution of a number of serious technical challenges. For example, the reductive coupling process is both endothermic and thermodynamically limited. Thus the cooling effect caused by the reaction lowers the reaction temperature sufficiently to greatly reduce the reaction rate and total thermodynamic conversion if significant make-up heat is not provided to the process.
Moreover, the process tends to produce carbon and other non-volatile materials that accumulate on the catalyst resulting in reduced activity and potentially undesirable selectivity shifts. In addition, at the high temperatures involved in the process, the active metal species (MoCx, WCx, etc) on the catalyst may migrate, agglomerate or change phase, again resulting in undesirable declines in conversion and selectivity. The catalyst is therefore subjected to frequent oxidative regeneration to remove the carbon and other non-volatile materials that have accumulated on the catalyst and possibly to redistribute the active metal species. However, depending on the composition of the catalyst, oxidative regeneration may have certain unwanted ancillary effects. For example, the metal on the catalyst may be converted from a catalytically active elemental or carburized state to a less active oxidized state. Also, following regeneration, the catalyst may exhibit enhanced activity for coke deposition and related hydrogen generation. Thus the present invention seeks to provide an improved method for regenerating a dehydroaromatization catalyst and subsequently tailoring its activity for use in the conversion of methane to aromatic hydrocarbons.
U.S. Patent Application Publication No 2003/0083535 discloses a process for aromatization of a methane-containing feed, in which a dehydroaromatization catalyst is circulated between a reactor system and a regenerator system, where the catalyst is contacted with different regeneration gases, including O2, H2, and H2O, at different times to regenerate different portions of catalyst. The percentage of catalyst contacting each regeneration gas is controlled to maintain the reactor system and regeneration system under a heat balance regime. The reactor system includes a fluidized bed of catalyst in a riser reactor, and the regeneration system includes a second fluidized bed of catalyst maintained in a bubbling bed reactor. After passage through the regeneration system, the hot regenerated catalyst is returned to the reactor system by way of a transfer system, which may include a reduction vessel for increasing the activity of the regenerated catalyst by contacting the catalyst in a fluidized bed with a reducing gas stream including hydrogen and/or methane.
However, processes that use the catalyst regeneration step to supply reaction heat, such as that described in the '535 publication, suffer from the problem that the catalyst needs to be heated well above the target reaction temperature in the regeneration process, which leads to accelerated catalyst degradation and hence reduced catalyst life. In addition, the entire catalyst inventory must be circulated between the reactor system and the regenerator system and hence is subject to the extreme conditions in the regenerator. Moreover, to maintain heat balance, the process requires a high selectivity to coke rather than to the desired aromatic products.


A method for fabricating a semiconductor package which includes coupling an electrode of a semiconductor device to a portion of a lead frame, overmolding at least a portion of the die, and then removing a portion of the die to obtain a desired thickness.

The present invention relates to semiconductor packages and more specifically relates to a process for the low cost manufacture of semiconductor packages.
Prior art power semiconductor packages typically include a housing which is frequently much larger than the semiconductor die it encapsulates. Further, in many known semiconductor device packages, heat is taken out only from one side of the die, usually the bottom surface.
Moreover, as the semiconductor die are reduced in size the size of the electrodes of the die are reduced which may increase the likelihood of failure due to solder joint degradation caused by electromigration and the like phenomenon.
In a method according to the present invention the electrodes of a semiconductor device are redistributed to larger pads, which are then used for external connection. As a result, failures resulting from the reduction in the size of electrodes can be reduced.
A method of fabricating a semiconductor package according to the present invention includes electrically and mechanically coupling one electrode on a front surface of a semiconductor die to one portion of a lead frame with a conductive adhesive body, providing overmolding for the semiconductor die, and removing at least a portion of the semiconductor die from the back surface thereof to a desired thickness.
In one embodiment of the present invention the lead frame includes a recess in which the semiconductor die is at least partially received, and the back surface of the die is plated to include a metallic body serving as a connection lead to the back surface of the die. The lead frame portion so coupled to the electrode of the semiconductor then serves a redistributed pad or lead for the die. The lead may have a connection surface coplanar with the plated metallic body, whereby all connection surfaces are disposed on the same plane for ease of mounting onto a circuit board or the like.
In another embodiment of the present invention the lead frame may be a flat metallic web such as a thick copper plate, which includes at least one portion defined by a passivation body for coupling to the electrode of the semiconductor die. The portion so defined is then patterned (isolated from the remaining body of the plate) to serve as the redistributed pad or lead for the semiconductor die. Similar to the first embodiment, the back of the die can be provided through plating or the like process with a metallic body.
Other features and advantages of the present invention will become apparent from the following description of the invention which refers to the accompanying drawings.

Semiconductor package with redistributed pads