Systems and processes for synchronous demodulation of signals in detection contexts in order to improve frequency, magnitude and/or phase response over pulsed signal methods. According to a preferred embodiment, a return signal is demodulated for the time corresponding to when its corresponding transmitting signal has been discontinued or has fallen below a certain level. Multiple transmission frequencies, transmitters, and or sensors, among other things, may be used.

This invention relates generally to demodulation of signals in detection systems.
One of the major problems in active transmit-receive detection systems is that the sensors that are supposed to pick up the response of the return signal from an object or secondary source, respond to the direct signal from the transmitter. This is a problem for several reasons. In most systems the transmitter signal is much larger than the return signal. In some systems this ratio can be over one million to one. Furthermore, in most systems the receive sensors are located physically closer to the transmitter than to the object that gives the return. Due to these factors, the desired sensor signal (the signal due to the return) is masked by the much larger sensor response to the direct signal. System designers spend great efforts to reduce the direct pickup by the sensors. In many cases the limiting sensitivity of a system is set by the system's ability to reduce the direct pickup of the sensors. This is especially true in continuous mode systems (systems that continuously transmit a signal).
To avoid this problem, systems were developed that transmitted relatively short pulses. The sensors were then set up to look only at the returns that came after the transmitter had stopped producing the pulse. FIG. 1. shows a typical transmitted pulse signal and its associated return signal. FIG. 2. shows the portion of the return signal that is recorded and analyzed by the pulsed system. In this manner the systems could transmit a relatively higher power pulse, albeit for a short period of time, that would not interfere with the return signal on the sensors. Since the pulse transmit times are relatively short the total transmitted energy is small. In these types of systems the elimination of the direct transmit signal at the sensor is related to the time it takes to turn off the transmitter and the waiting time between the pulse end and the time the sensor starts responding to the return signal. The nature of the laws of physics means that no real system can stop transmitting a signal instantaneously. This means that the system must wait until the direct signal at the sensor falls below a given level before it can use the sensor for detecting the return. These factors along with the response of the object to the transmitted signal govern the system's responsivity to the object.

Systems and methods for synchronous detection of signals


A new technique for image sample-rate conversion can be efficiently implemented with respect to memory, bandwidth and computational requirements. According to one aspect, the technique takes advantage of certain inherent similarities and symmetries within the image data to limit switching of filters during processing and to otherwise process the data in an efficient order. According to another aspect, the technique can be implemented within a decoding pipeline such as a JPEG/MPEG decoding pipeline in such a way that multiple transfers of image data in and out of the external memory can be avoided. According to a still further aspect, where poly-phase filters are used, computationally-efficient filters are chosen for use with the image conversion process. The technique is amenable to both hardware and software based implementations.

Taking and displaying of still and video images are becoming ubiquitous. Consider, for example, the recent explosion in the popularity of cameras in cell phones and image/video displays in portable music players, for example.
Resolutions of image/video content that are available in the market place today vary quite dramatically. For example, digital still cameras are capable of producing images whose resolutions currently can vary from as small as 320×240 pixels to as large as 3072×2048 pixels.
Meanwhile, typical display units like a TV monitor or a LCD display in hand-held devices are only capable of displaying images with much smaller resolutions. For example, TV monitors generally support images at NTSC or PAL resolution (720×280 or 720×576, respectively) while most low-cost LCD display units support images up to 320×240 pixels. Obviously, the input images are significantly greater than the resolutions typically supported by the display units.
There are two known ways to handle this mismatch. In the first, the display rectangle can be overlaid on top of the larger image. The user can then interactively move the cursor to view different regions of the larger image (i.e. panning). The second way is to scale the entire input image to fit to the dimensions of the display window (i.e. scaling). Both schemes have advantages and disadvantages and therefore it is a general practice to support both schemes. For example, in the first scheme, only the portion of the picture is visible to the viewer at any time, while in the second scheme, the image has to be modified to fit the viewing area.
For the second scheme, a two-dimensional sample-rate converter (i.e. scaler) is typically used. Accordingly, as shown in FIG. 1, an image converter 100 receives an input image and up-scales or down-scales the image to produce an output display image in accordance with the resolution of the input image and the resolution of the display. Since the input resolutions of the images can change from image to image, the up-sampling/down-sampling ratio (the ratio of the output dimension to the input dimension) can also change from image to image, even if the image display resolution remains the same.
In addition, the spatial relationship between input and output samples also changes, on a sample-by-sample (i.e. pixel-by-pixel) basis. For example, assume that there is a need to down-sample an image by a factor of 5/16. In other words, for each row and column of sixteen input samples, five output sample will need to be created. In such an example, as shown in FIG. 2, pixels a and b are input samples in an input image row 202 having sixteen input samples and pixels A and B are output samples in an output image row 204 that need to be calculated. Depending on the spatial location of the output pixels with respect to the input pixels, the formula to calculate the output pixel value can change.
More particularly, poly-phase filters are typically used to compute the output pixel values. In such a technique, the filter that is used for each output sample is selected dynamically from a predetermined set of filters depending on the sampling ratio that needs to be achieved and the spatial relationship or phase between the output sample and the input sample(s). Accordingly, with reference to FIG. 2, the filter that is applied to the input samples to compute output pixel A will likely be different from the filter that is applied to the input samples to compute pixel B, given the different spatial relationship or phase between input pixels a and b, respectively (i.e. phasea≠phaseb). This approach, when applied on a sample-per-sample basis as is conventionally done, consumes considerable computation resources, and thus makes implementing such techniques in any time critical application quite challenging.
An example of a conventional horizontal scaling process using poly-phase filters will now be described in more detail in connection with FIG. 3, and the example down-sampling ratio illustrated in FIG. 2.
As shown in FIG. 3, processing begins in step S302 by determining the index of the first/next output sample to compute. Referring to FIG. 2, the first output sample to be computed corresponds to sample A, which has an index of 1. Next, in step S304, the index of the corresponding input sample is determined based on the scaling factor. With reference to the example of FIG. 2, this is obtained by trunc (output index*Δout/Δin)=trunc (1*16/5)=trunc (3.2)=3.
Processing advances to step S306, where the filter to apply to the input sample(s) including and adjacent to input index 3 (i.e. pixel a) is selected. This is typically determined based on the spatial relationship between the given input sample and output sample. For example, a set of filters is predetermined and indexed in order depending on the increasing size of spatial "error" or phase between the output sample and the input sample. Accordingly, referring to FIG. 2, the index of the filter to use for determining output sample A will be lower than the index of the filter to use for determining output sample B, given that output sample A is spatially closer to corresponding input sample a than output sample B is relative to corresponding input sample b (i.e. phasea<phaseb). More specifically, for output sample A, the phase or error with respect to the corresponding input sample a is determined as rem (output index*Δout/Δin)=rem (1*16/5)=rem (3.2)=0.2, and the index of the filter to select is determined by round (error*# phases). In an example where a set of 8 poly-phase filters are used, the index of the filter to select is round (0.2*8)=round (1.6)=2. Alternatively, the filter index can be determined by rem (round (# phases*(output index*Δout/Δin))/# phases)=rem ((round (8*(1*16/5)))/8)=rem (round (25.6)/8)=rem (26/8)=2.
In step S308, the selected filter is applied to the input sample(s) to calculate the output sample. Depending on the number of taps in the filter, the corresponding number of input samples adjacent to and including the determined input sample will be retrieved and used to calculate the output sample.
In step S310, it is determined whether the end of the row of output samples has been reached. If not, processing returns to step S302. Otherwise processing advances to step S312, where it is determined if the last row of output samples has been calculated. If so, horizontal scaling processing ends. Otherwise processing advances to step S314, where the output index is reset to the beginning of the next row before returning to step S304.
It should be noted that vertical scaling can be performed in similar fashion as described in connection with FIGS. 2 and 3 above. It should be further noted that the conventional approach to scaling, when applied on a sample-per-sample basis as is conventionally done, consumes considerable computation resources, and thus makes implementing such techniques in any time critical application quite challenging.
In addition to the afore-mentioned problems with conventional scaling techniques, the pixel data to the scaler unit typically arrives as two-dimensional blocks of varying sizes. For example, the scaler unit may be part of a processing pipeline including a JPEG or MPEG decoder. The output of a JPEG decompression module may include block sizes of 8×8, 16×16, 16×8 and 8×16 (an MPEG decoder block output is typically 16×16). As a result, most current systems will separate the JPEG/MPEG decoding process from the scaling process.
More particularly, as shown in FIG. 4, since the amount of SRAM is limited in most embedded processors, the image will first be decoded by a JPEG decoder and stored in external memory and then will be read again from memory for the scaling process. Further, since the scaling is a two-dimensional process, typically, because of memory constraints, the images will first be horizontally scaled on a pixel-line basis, stored back to external memory, and then the horizontally-scaled pixel lines will be read from memory, and vertically scaled to obtain the desired resolution. This involves multiple reads and writes to the external memory.
Accordingly, it would be desirable if a sample-rate conversion technique could efficiently convert images without the computation, memory and bandwidth requirements of conventional techniques that are applied in standard pipelines such as a JPEG or MPEG decoding pipeline.

Memory and compute efficient block-based two-dimensional sample-rate converter for image/video applications


An N-input transistor logic circuit includes two or four series-connected transistor arrays connected between two power lines. The gates of the transistors are connected to the N inputs to account for varying parasitic input capacitances, and equalizes the resulting time delays between the N-inputs and the logical unit output. Specifically, in each of the arrays each of the transistors is connected to one of the N inputs, and is separated from a first power line by X other transistors in the respective array. For each of the input terminals, the sum of X for all the arrays is a constant, namely, 2N-2 for four arrays and N-1 for two arrays.

This invention relates to a logical circuit comprising a plurality of transistors connected in series for use in an NAND circuit, an NOR circuit, or the like having a plurality of inputs and, in particular, to a semiconductor integrated circuit arrangement for integrating the logical circuit by the use of a semiconductor.
As an N-input NAND circuit constituted by the use of MOS (metal oxide semiconductor) transistors as MIS (metal insulator semiconductor) transistors, a logical circuit is known which has a logical unit including n-channel MOS transistors, N in number, connected in series or cascade, where N represents an integer greater than one. As an N-input NOR circuit, another logical circuit is known which has another logical unit including p-channel MOS transistors, N in number, connected in series or cascade. In the above-mentioned logical circuits, it is desired to design the circuit so as to avoid occurrence of time lag of outputs for different inputs due to unbalance in input wires (including gates) and gate capacitance and junction capacitance appearing in the output.
A conventional logical circuit of the type is disclosed in Japanese Unexamined Patent Publication (JP-A) No. 202616/1967 (hereinafter called prior art).
In the prior art, a logical unit for switching operation in the NAND circuit (or the NOR circuit) comprises transistor arrays, N or N! in number, connected in parallel, each transistor array comprising n-channel MOS transistors (or p-channel MOS transistors), N in number, connected in series or cascade. The n-channel or the p-channel MOS transistors in the respective arrays are arranged so that their gates are connected in a cyclic fashion.
In the NAND or the NOR circuit of the prior art having the above-mentioned structure, difference in delay time of outputs for different inputs may be eliminated.
However, in the above-mentioned prior art, it is necessary to use a large number of transistors in the logical unit as the number N of the inputs increases. This increases the required art area and complicates the layout of interconnection between the transistors. For example, in case of five inputs (that is, N is equal to 5), the number of transistors used In the logical unit is as enormously large as 5.times.5 (=N.times.N) or 5!=5.times.4.times.3.times.2.times.1 (=N!).
The prior art shows electrical circuit diagrams alone. No description is provided about disadvantages in cases where the circuit shown in the prior art is practically implemented as an integrated circuit. Therefore, when the circuit exemplified in the prior art is straightforwardly integrated, the increase in area is inevitable following the increase in number of required devices.
It is noted here that the increase in area directly results in the increase in chip area. This is a bar against downsizing of a chip. In addition, the increase in number of the devices makes the layout of interconnection lengthy and complicated. This often results in an inbalance in the interconnections.

Logical circuit capable of uniformizing output delays for different inputs


A position structure of a liquid crystal display for positioning a display panel in a display cover is disclosed. The position structure includes a position piece, a position protrusion, and a position breach. The position piece is placed between the display panel and the display cover to absorb a tolerance between the display panel and the display cover. The position protrusion is formed on a sidewall of the display cover and the position breach is formed on the position piece. The position breach is disposed corresponding to the position protrusion. The position protrusion may couple with the position breach to fix the position piece between the display panel and the display cover.

1. Field of Invention
The present invention relates to a liquid crystal display (LCD). More particularly, the present invention relates to a position structure of the LCD.
2. Description of Related Art
Liquid crystal displays (LCD) has many advantages over other conventional types of displays including high display quality, small volume occupation, lightweight, low voltage driven and low power consumption. Hence, LCD are widely used in portable devices, such as small televisions, mobile telephones, video recording units, notebook computers, desktop monitors, projector televisions and so on. Therefore, LCDs have gradually replaced the conventional cathode ray tube (CRT) as a trend for display unit.
The main LCD components include a display panel and a display cover. The display panel may be screwed in the display cover. However, an unwanted tolerance is generated when the display panel and the display cover are fabricated, and a gap is formed between the display panel and the display cover. Thus, the display panel is difficult to be positioned firmly and the display panel may be damaged easily while colliding with the display cover and.
For the foregoing reasons, there is a need for reducing the display panel position inaccuracy caused by the tolerance in the LCD.

Position structure of liquid crystal display


An integrated lead disk drive suspension flexure including a gimbal region including gimbal spring arms having conductive spring metal traces embedded within dielectric between a pair of conductive metal shields. The traces function as the spring arms of the gimbal spring arms, wherein the gimbal spring arms are free from spring metal layers opposite the pair of conductive metal shields from the spring metal trace supports.

Wireless or integrated lead flexures of the type used in magnetic disk drive head suspension assemblies and associated manufacturing methods are known and disclosed, for example, in the following U.S. Patents.
InventorU.S. Pat. No./Publication No.Hamilton et al.5,490,027Balakrishnan5,995,328Omote et al.6,100,582Bennin et al.6,587,310Kangawa et al.2005/0122627
There remains, however, a continuing need for improved flexures and methods of manufacture. In particular, there is a need for flexures having both high performance mechanical characteristics and high performance electrical signal transmission characteristics. To be commercially viable the flexures must be capable of being efficiently manufactured to a high degree of precision.

Shielded copper-dielectric flexure for disk drive head suspensions


An amplifier system can include a biasing amplifier that provides a first amplified signal to a DC blocking element that is connected with a load based on a first control signal. A power amplifier provides a second amplified signal for driving the load based on a second control signal. A control system controls the biasing amplifier to charge the DC blocking element so as to mitigate a voltage drop across the load (e.g., to substantially eliminate audible artifacts) when the power amplifier is activated to provide the second amplified signal.

Transient signals in an electrical circuit can cause a number of problems in certain applications. Transient signals that have sufficiently high voltage or current can damage electrical circuitry or otherwise adversely affect performance of one or more components. A transient voltages is usually the result of a sudden, sharp change in voltage across a circuit component that is often is associated with initiating power to a load. In some applications, transient signals may not damage components, but nonetheless provide undesirable effects and/or reduce performance.
In a number applications, particularly relating to audio systems, it is desirable to eliminate or substantially reduce transient voltages across certain loads to reduce adverse impacts of such transient voltage on performance. Click/pop is one such undesirable result of transient voltages. Click/pop is an unpleasant audible artifact provided by a speaker, which is often heard when an audio system powers up or powers down. Click/pop is generally caused by a transient voltage drop (e.g., a DC offset mismatch) across a speaker that may occur when a power amplifier transitions between a non-switching mode and a switching mode.
The audibility of click/pop does not depend only on the energy involved, but also on how the energy spectrum is shaped. While click/pop is most often heard when the audio amplifier system is powered on, click/pop can also occur when the audio system is powered down, or when the audio system changes mode. The mode changes include changing from surround mode to stereo mode, or from stereo to mono mode or between different surround sound modes.

System and method for reducing audible artifacts in an audio system


An assembly tool (20) for a securing system. (1) The securing system comprises an elongate profiled-section element (2) having a longitudinal slot (6), which is delimited by two flanges, and an elongate nut body (3). The nut body is of a width which is less than the width of the longitudinal slot and a length (1) which is greater than the width of the longitudinal slot. The nut body is provided with a bore (8) and, on an underside, with a downwardly projecting spring (13).

1. Technical Field of the Invention
The invention relates to an assembly tool for a securing system comprising:                an elongate profiled-section element having a top side which is provided with two flanges which delimit a longitudinal slot, and which profiled-section element also has a base lying opposite the top side,        an elongate nut body of a width which is less than the width of the longitudinal slot in the profiled-section element and a length which is greater than the width of the longitudinal slot in the profiled-section element, which nut body also has a top side, an underside and, surrounding it, two short sides and two long sides, the nut body also being provided with a bore and on the underside being provided with a downwardly projecting spring.
During assembly, the longitudinal axis of the nut body is brought into line with the longitudinal slot, and the nut body is introduced into the profiled-section element between the flanges with the underside facing towards the base of the profiled-section element, so that the spring engages on the base of the profiled-section element. Then, the nut body is rotated in order to engage behind the flanges, with the spring pressing the nut body towards the top side of the profiled-section element and onto the flanges.
2. Prior Art
A securing system of the type described above is known, for example, from EP 0 516 321. In a securing system of this type, it is known to introduce the nut body into the profiled-section element by hand. In the process, the nut body is pushed between the flanges of the profiled-section element, counter to the spring force, using one or more fingers, and then the nut body is rotated, an operation which generally requires two fingers.
Arranging a nut body in a profiled-section element by hand in this way is laborious and in practice causes problems on account of the frequently small size of the nut bodies used and the small slot width of the profiled-section element, with the result that the space available for the fingers during introduction and rotation of the nut is small. One or more fingers can become trapped. The opposite force exerted by the spring also makes it more difficult to introduce and rotate the nut body.
It is an object of the invention to facilitate the mounting of the nut body in a profiled-section element in a system of this nature.

Assembly of a nut body in a profiled-section element


A method of manufacturing a polysilicon layer is provided. Firstly, a substrate is provided. Next, an amorphous silicon having a first region and a second region is formed on the substrate. After that, the amorphous silicon layer in the first region is completely melted and the amorphous silicon layer in the second region is preheated. The completely melted amorphous silicon layer in the first region is crystallized to form a first polysilicon layer. Next, the preheated amorphous silicon layer in the second region is completely melted. The completely melted amorphous silicon layer in the second region is crystallized to form a second polysilicon layer.

1. Field of the Invention
The invention relates in general to a method of manufacturing a polysilicon layer, and more particularly to a method of manufacturing a polysilicon layer using a mask for the laser beam to preheat an amorphous silicon layer and completely melt the preheated amorphous silicon layer, and the mask therein.
2. Description of the Related Art
With the rapid development in science and technology, display panel has been widely used in electronic devices such as notebook, personal digital assistant (PDA) and mobile phone. The display panel has two categories, namely, the amorphous silicon (a-Si) thin film transistor (TFT) display panel and the low temperature polysilicon (LTPS) TFT display panel. The main difference between the LTPS TFT display panel and the amorphous silicon TFT display panel is that the LTPS TFT display panel converts an amorphous silicon layer into a polysilicon layer via laser annealing, largely enhancing the electron mobility of the TFT. The panel driving circuit and the integrated circuit (IC) can be integrated into the LTPS TFT display panel without having extra circuit board design, largely increasing the flexibility in the design of panel and circuit. Therefore, the LTPS TFT display panel is a display panel with great potential.
Referring to FIGS. 1A˜1C, flowchart diagrams of a conventional method of manufacturing a polysilicon layer are shown. Firstly, the method begins at FIG. 1A: a substrate is provided 11 and an amorphous silicon layer is formed 12 on the substrate 11. Next, a mask 15 having a non-transparent region 15a and a transparent region 15c is provided atop of the amorphous silicon layer 12, and a laser beam 16 is projected onto the mask 15. Next, as shown in FIG. 1B, the laser beam 16 penetrates through the transparent region 15c and completely melts part of the amorphous silicon layer 12 for the melted amorphous silicon layer 12b and the remaining amorphous silicon layer 12a to be formed on the substrate 11. Since temperature gradient exists between the remaining amorphous silicon layer 12a and the melted amorphous silicon layer 12b, the temperature of the melted amorphous silicon layer 12b is higher than the temperature of the remaining amorphous silicon layer 12a, enabling the melted amorphous silicon layer 12b to use the remaining amorphous silicon layer 12a as seed crystal to laterally form crystallization and become a polysilicon layer 13 along the direction of the arrows 20a and 20b as shown in FIG. 1C. The technology, which uses a laser beam 16 to penetrate through a mask 15 having a non-transparent region 15a and a transparent region 15c to completely melt part of the polysilicon layer 12 for the polysilicon layer 12 to form crystallization laterally, is called the sequence lateral solidification (SLS) method or the excimer laser annealed lateral crystallization (ELA-LC) method. In FIG. 1C, the polysilicon layer 13 has a crystal lattice or boundary 13b. Furthermore, the polysilicon layer 13 corresponds to a defect 13a projected from the surface of the crystal lattice or boundary 13b, affecting the adhesiveness between the insulation layer and the polysilicon layer 13 afterwards.
The distance of lateral crystallization can be enlarged by prolonging laser pulse duration time or by heating the substrate 11 to prolong the silicon melting time. However, according to conventional practice, the manufacturing facility must have a substrate heater to heat the overall piece of the substrate 11. In order to have optimum energy for the temperature gradient and the laser beam 16 to melt the amorphous silicon layer 12, the method of heating the overall piece of the substrate 11 would increase the optimum energy, largely shortening the lifespan and the maintenance period of the laser beam optical module. Besides, the polysilicon layer 13 formed according to the laser annealing method have a large number of defects 13a existing on the crystal lattice or boundary 13b. Although the defects 13a can be repaired by using the laser beam 16 again or using high-temperature treatment, additional manufacturing steps and manufacturing costs would occur. Besides, only part of the laser beam 16 would penetrate through the transparent region 15c and melt part of the amorphous silicon layer 12, so another part of the laser beam 16 would be partly reflected and absorbed by the non-transparent region 15a and converted into heat, resulting in a poor utilization rate of the laser beam 16.

Method of manufacturing a polysilicon layer and a mask used therein


A power converter suitable for use in an uninterruptible power supply (UPS) includes first and second voltage busses, an input port having a first terminal coupled to one of the first and second voltage busses, a neutral bus and an output terminal. A first switching circuit selectively couples a second terminal of the input port to the first and second voltage busses. A second switching circuit selectively couples the first and second voltage busses to the output terminal. A third switching circuit selectively couples the first and second voltage busses to the neutral bus. Preferably, the first, second and third switching circuits are operative to produce an AC output voltage at the output terminal from a DC input voltage at the input port such that alternating ones of the first and second terminals of the first input port are referenced to the neutral bus for successive first and second half cycles of the AC output voltage. According to other embodiments, a DC voltage generating circuit is operative to produce respective first and second DC voltages on first and second voltage busses. A first switching circuit is operative to selectively couple the first and second voltage busses to the output terminal. A storage circuit connected to the output terminal includes a capacitive storage element, a rectifying circuit coupling the capacitive storage element to the output terminal, and a second switching circuit operative to selectively couple the capacitive storage element to the output terminal.

The present invention relates to electrical power devices and methods of operation thereof, and more particularly, to power conversion devices and methods of operation thereof.
Uninterruptible power supplies (UPSs) are power conversion devices that are commonly used to provide conditioned, reliable power for computer networks, telecommunications networks, medical equipment and the like. UPSs are widely used with computers and similar computing devices, including but not limited to personal computers, workstations, mini computers, network servers, disk arrays and mainframe computers, to insure that valuable data is not lost and that the device can continue to operate notwithstanding temporary loss of an AC utility source. UPSs typically provide power to such electronic equipment from a secondary source, such as a battery, in the event that a primary alternating current (AC) utility source drops out (blackout) or fails to provide a proper voltage (brownout).
Conventional UPSs may be classified into categories. Referring to FIG. 1, a typical conventional off-line UPS disconnects a load from a primary AC source 10 when the primary AC source fails or is operating in a degraded manner, allowing the load to be served from a secondary source such as a battery. The AC power source 10 is connected in series with a switch SI, producing an AC voltage across a load 20 when the switch S1 is closed. Energy storage is typically provided in the form of a storage capacitor CS. The secondary power source, here a battery B, is connected to the load 20 via a low voltage converter 30 and a transformer T. When the AC power source 10 fails, the switch SI is opened, causing the load to draw power from the battery B. The low voltage converter 30 typically is an inverter that produces a quasi-square wave or sine wave voltage on a first winding L1 of the transformer T from a DC voltage produced by the battery B. The first winding L1 is coupled to a second winding L2 of the transformer T connected across the load 20. When the AC power source is operational, i.e., when the switch S1 is closed, the battery B may be charged using the low-voltage converter 30 or a separate battery charger circuit (not shown).
A line interactive (LIA) UPS topology is illustrated in FIG. 2. Here, the transformer T has a third winding L3 that may be connected in series with the load 20 using switches S2, S3 to xe2x80x9cbuckxe2x80x9d or xe2x80x9cboostxe2x80x9d the voltage applied to the load 20. As with the offline UPS topology of FIG. 1, when the AC power source 10 fails, the switch S1 can be opened to allow the load 20 to run off the battery B.
As illustrated in FIG. 3, a typical on-line UPS includes a rectifier 40 that receives an AC voltage from an AC power source 10, producing a DC voltage across a storage capacitor CS at an intermediate node 45. An inverter 50 is connected between the intermediate node 45, and is operative to produce an AC voltage across a load 20 from the DC voltage. As shown, a battery B is connected to the intermediate node 45 via a DC/DC converter 60, supplying auxiliary power. Alternatively, the DC/DC converter can be eliminated and a high-voltage battery (not shown) connected directly to the intermediate node 45.
Each of these topologies may have disadvantages. For example, typical conventional on-line and LIA UPSs for 60 Hz applications use 60 Hz magnetic components (e.g., transformers and inductors) that are sized for such frequencies, and thus may be large, heavy and expensive. LIA UPSs often exhibit step voltage changes that can affect the performance of the load. Conventional off-line, LIA and on-line UPSs often use large storage capacitors, which tend to be bulky and expensive, in order to maintain an acceptable output voltage under heavy loading conditions. Moreover, because conventional UPSs are typically designed to operate in only one of the above-described off-line, LIA or on-line modes, sellers of UPSs may be required to maintain large inventories including several different types of UPSs in order to meet a variety of different customer applications.
According to embodiments of the present invention, a power converter, such as one that might be utilized in an uninterruptible power supply (UPS), includes first and second voltage busses, a first input port having a first terminal coupled to one of the first and second voltage busses, a neutral bus and an output terminal. A first switching circuit selectively couples a second terminal of the first input port to the first and second voltage busses. A second switching circuit selectively couples the first and second voltage busses to the output terminal. A third switching circuit selectively couples the first and second voltage busses to the neutral bus. Preferably, the first, second and third switching circuits are operative to produce an AC output voltage at the output terminal from a DC input voltage at the first input port such that alternating ones of the first and second terminals of the first input port are referenced to the neutral bus for successive first and second half cycles of the AC output voltage.
In embodiments of the present invention, the first switching circuit includes a first inductance having first and second terminals, the first terminal of the first inductance coupled to the second terminal of the first input port. The first switching circuit further includes a first switch is operative to couple and decouple the second terminal of the first inductance and the first voltage bus and a second switch operative to couple and decouple the second terminal of the first inductance and the second voltage bus. The second switching circuit includes a second inductance having first and second terminals, the first terminal of the second inductance coupled to the output terminal. The second switching circuit further includes a third switch operative to couple and decouple the second terminal of the second inductance and the first voltage bus and a fourth switch operative to couple and decouple the second terminal of the second inductance and the second voltage bus. The third switching circuit includes a third inductance having first and second terminals, the first terminal of the third inductance connected to the neutral bus. The third switching circuit also includes a fifth switch operative to couple and decouple the second terminal of the third inductance and the first voltage bus and sixth switch operative to couple and decouple the second terminal of the third inductance and the second voltage bus.
In other embodiments of the present invention, a power converter further includes a second input port. A fourth switching circuit concurrently couples the second terminal of the first input port to the second voltage bus, decouples the second terminal of the first input port from the first switching circuit, and couples the first switching circuit to a first terminal of the second input port, in a first mode. The fourth switching circuit concurrently couples the second terminal of the first input port to the first switching circuit, decouples the second terminal of the first input port from the second voltage bus, and decouples the first terminal of the second input port from the first switching circuit, in a second mode.
According to other aspects of the present invention, a power converter includes first and second voltage busses, a neutral bus, and an output terminal. A DC voltage generating circuit is operative to produce respective first and second DC voltages on the first and second voltage busses. A first switching circuit is operative to selectively couple the first and second voltage busses to the output terminal. A storage circuit is connected to the output terminal, and includes a capacitive storage element, a rectifying circuit coupling the capacitive storage element to the output terminal and operative to produce a DC voltage across the capacitive storage element from an AC output voltage at the output terminal, and a second switching circuit operative to selectively couple the capacitive storage element to the output terminal.
In embodiments of the present invention, the first switching circuit includes a first inductor having first and second terminals. The first terminal of the first inductor is coupled to the output terminal and respective first and second switches are operative to selectively couple the second terminal of the inductor to the first and second voltage busses. The storage circuit is electrically coupled to the output terminal through a second inductor that is inductively coupled to the first inductor.
According to still other embodiments of the present invention, the storage circuit includes first and second storage busses. The capacitive storage element includes respective first and second capacitors coupling respective ones of the first and second storage busses to the neutral bus. The second switching circuit includes a third switch operative to couple and decouple the first storage bus and the output terminal and a fourth switch operative to couple and decouple the second storage bus and the output terminal. According to an aspect of the present invention, the first and third switches open and close in synchronism, and the second and fourth switches open and close in synchronism.
According to other aspects of the present invention, the DC voltage generating circuit includes a rectifying circuit configured to connect to an AC power source at an AC input port and operative to produce the first and second DC voltages on the first and second voltage busses from an AC input voltage applied to the DC voltage generating circuit. The rectifying circuit, the first switching circuit and the second switching circuit are operative to produce the AC output voltage at the output terminal while maintaining a substantially unity power factor at the AC input port.
According to method aspects of the present invention, an AC output voltage is generated at a load from a DC input voltage produced by a DC power source by coupling a first terminal of the DC power source to one of a first voltage bus and a second voltage bus. A second terminal of the DC power source is selectively coupled to the first voltage bus and a second voltage bus through respective first and second switches. A first terminal of a load is coupled to a neutral bus. The first and second voltage busses are selectively coupled to a second terminal of the load through respective third and fourth switches. The first and second voltage busses are selectively coupled to the neutral bus through respective fifth and sixth switches. Preferably, the first and second terminals of the DC power source are alternatingly referenced to the neutral bus for successive first and second half cycles of the AC output voltage.
According to other method aspects of the present invention, an AC output voltage is produced at a load by generating respective first and second DC voltages on the first and second voltage busses. The first and second voltage busses are selectively coupled to the load through respective first and second switches to generate an AC output voltage at the load. First and second capacitors are rectifyingly coupled to the load to produce respective first and second DC voltages across respective ones of the first and second capacitors from an AC output voltage at the load. The first and second capacitors are selectively coupled to the load through respective third and fourth switches to transfer power between the first and second capacitors and the load.

Power converters with AC and DC operating modes and methods of operation thereof


A reforming device includes a reforming portion generating reformed gas from a mixed gas, in which fuel and steam are mixed and including a reforming portion loop-back channel provided at the reforming portion so as to extend along an axis line thereof, a combusting portion provided at an inner circumference of the reforming portion in order to generate combustion gas, a combustion gas channel including a loop-back channel within which the combustion gas flows, an evaporating portion generating steam by heating water and supply steam to the reforming portion; and a carbon monoxide reducing portion provided at an outer circumferential wall of the evaporating portion in order to reduce a level of carbon monoxide in the reformed gas that has been exhaled by the reforming portion, and in order to supply such reformed gas to a fuel cell.

A known reforming device generates reformed gas, which is a so-called hydrogen rich gas, from a mixture of supplied fuel (e.g., natural gas, liquefied petroleum gas, kerosene, methanol or the like) and steam. The generated reformed gas is supplied to, for example, a fuel electrode of a fuel cell. The fuel cell generates power by use of hydrogen existing in the reformed gas, which is exhaled to he fuel electrode, and oxygen existing in the air, which is exhaled to an air electrode.
A known reforming device includes a reforming portion generating a reformed gas, in which fuel and steam are mixed, and exhausting the reformed gas, a combusting portion generating combustion gas, which is used for heating the reforming portion, a combustion gas channel through which the combustion gas flows, a evaporating portion generating the steam by heating water and supplying the steam to the reforming portion, a carbon monoxide reducing portion reducing the level of carbon monoxide in the reformed gas, which is exhaled by the reforming portion, and supplying the reformed gas to the fuel portion.
According to a hydrogen generating device (reforming device) disclosed in JP2003-252604A, as shown in FIG. 1, a tubular reforming vessel 10 (reforming portion) is installed so as to surround a combustion chamber 17, and a tubular pass 12 flowing a fuel gas on the periphery of the reforming vessel 10 and a tubular evaporating chamber 28 (evaporating portion) on the periphery of the pass 12 flowing the fuel gas are coaxially installed, respectively. The evaporating chamber 28 consists of a first evaporating chamber 18 and a second evaporating chamber 22 installed away from the first evaporating chamber 18 by a partition wall 21. A plurality of open holes 23 is formed on the partition wall 21.
The single tubular cylinder type reforming apparatus (reforming device) disclosed in JP2003-321206A includes an emission tube 14 and a burner 18 (combusting portion). Specifically, the emission tube 14 is positioned inside of circular cases 61 through 66, which are provided perpendicularly, coaxially therewith, the burner 18 is positioned at the upper portion of the emission tube 14. Further, channels are formed between each of the circular cases 61 trough 66, and such channels are filled with a reforming catalyst. The single tubular cylinder type reforming apparatus further includes an outlet channel (combustion gas channel) 80, a channel 50, a CO transformer catalyst layer 10 (a part of a carbon monoxide reducing portion), a water heating channel 34, a heating channel 48, a connecting tube 25 and a CO removal catalyst layer (a part of the carbon monoxide reducing portion) 12. Specifically, combustion gas is inhaled into the outlet channel 80 and exhaled through a heat transmission channel (combustion gas channel) 27, which is formed toward outside of the reforming apparatus, after flowing within outer circumferential portion of the emission tube 14. The channel 50 is formed at an outer circumference of the reforming catalytic layer 8, within which the reforming catalyst is filled, and the channel 50 is connected to the reforming catalytic layer 8 at each lower end portion thereof. The CO transformer catalyst layer 10 is provided at an outer circumference of the channel 50, and the CO transformer catalyst layer 10 is connected to the channel 50 at each upper end portion thereof. The water heating channel 34, provided at an upper circumference of the heat transmission channel 27 at upper portions of the circular cases 61 through 66, heats water by means of the heat emitted from the burner 18. The heating channel 48 is formed at an outer circumference of the CO transformer catalyst layer 10 so as to be connected to an inlet 26 at a lower end of the heating channel 48 and connected to an opening of the reforming catalytic layer 8 at an upper end of the heat channel 48. The water heating channel (evaporating portion)34 is connected to an lower end portion of the heating channel 48 by means of a connecting tube 25. The CO removal catalyst layer 12 is provided at an outer circumference of the water heating channel 34.
According to the hydrogen generating device disclosed in JP2003-252604A, heat is exchanged between a basic ingredient X and water Y flowing within the evaporating chamber (evaporating portion)28; and combustion gas flowing within the combustion gas channel 12 in order to preheat the basic ingredient X and the water Y. However, because the evaporating chamber 28 is positioned at most outer circumference of the device, the heat transmitted to the basic ingredient X and the water Y may be emitted outside of the device through an outer circumferential wall of the evaporating chamber 28. Thus, efficiency of the heat exchange has been decreased.
Further, according to the single tubular cylinder type reforming apparatus disclosed in JP2003-321206A, because the CO removal catalyst layer 12 is provided at an outer circumference of the water heating channel 34, which is provided at an outer circumference of the outlet channel (combustion gas channel) 80, a chance can be reduced of the heat, which is emitted outward from the outlet channel 80, being emitted outward from through the outer circumferential wall of the water heating channel 34. Thus, the heat can be exchanged with appropriate efficiency. However, inside of the outlet channel 80, the heating channel 48 and the CO transformer catalyst layer 10 are provided in that order, the heat emitted inward from the outlet channel 80 is transmitted to the source gas flowing through the heating channel 48, and further transmitted to the CO transformer catalyst layer 10. Thus, because a temperature of the combustion gas cannot be increased to a required temperature, and water flowing within the water heating channel 34 cannot be heated appropriately, it takes some time to start the device, as a result, a level of starting performance may be decreased. In order to increase the level of the starting performance, the level of the combustion load can be increased, or the amount of water supplied to the device can be reduced. However, when the combustion load increased, the efficiency may be decreased, and when the amount of water is reduced, deterioration by carbon deposition on the reforming catalyst, which reaches a high temperature; reduction on a degree of conversion and increment of consistency of carbon monoxide within CO transformer catalyst layer 10 may occur.
Thus, because the heat emitted inward from the outlet channel 80 is transmitted to source gas flowing within he heating channel 48 and further transmitted to the CO transformer catalyst layer 10, a difference of responsibilities exists between the combustion gas and the reformed gas flowing within the CO transformer catalyst layer 10, consequently, heat may be imbalanced when the load is changed, as a result, consistency of the carbon monoxide may be increased due to change of the temperature.
A need thus exists to provide a reforming device that can increase efficiency of the heat exchange by reducing the heat emitted from the evaporating portion in which water is heated by means of the combustion gas, at the same time, even when the load is changed or the environment is changed, the device can stably controls with high robustness.


A pinhole-imaging device is used as an imaging device for an optical scanner apparatus. The pinhole-imaging device replaces the conventional lens-imaging device and is placed in front of the optical sensor to receive the imaged light from the scanning object and the optical image is focused on the optical sensor. When the radius of the aperture of pinhole-imaging device is smaller or equal to the pixel of the optical sensor, the imaged light transmitted through the aperture of the pinhole-imaging device is focused on the optical sensor to form an image such that the resolution of the optical imaging can be obtained and the light dispersion effect issue can be improved.

1. Field of the Invention
The present invention generally relates to an optical scanner apparatus, and more particularly to an imaging device of an optical scanning module to prevent the light dispersion effect and obtain the better mtf (modulation transfer function).
2. Description of the Prior Art
Scanner devices, such as flatbed scanners, are well known in the art and produce machine-readable image data signals that are representative of scanned object, such as a photograph or a page of printed text. In a typical scanner application, the image data signals produced by a scanner may be used by personal computer to reproduce an image of the scanned object in a suitable display device, such as a CRT (cathode ray tube) or a print.
Flatbed scanners are widely used with computer systems for converting printed data into image signals. An optical scanning module is the most important component of the flatbed scanner. The scanning module commonly comprises a housing with an opening for receiving light transmitted from a scanning object, an optical sensor such as CCD (charge coupled device) installed inside the housing for converting the transmitted light into corresponding image signals, and a plurality of lenses for focusing the transmitted light onto the optical sensor.
A typical flatbed scanner may include illumination and optical systems to accomplish scanning of the object. The illumination system illuminates a portion of the object (commonly referred to as a "scan region"), whereas the optical system collects light reflected by the illuminated scan region and focuses a small area of the illuminated scan region (commonly referred to as a "scan line") onto the surface of a photosensitive detector positioned within the scanner. Image data representative of the entire object then may be obtained by sweeping the scan line across the entire object, usually by moving the illumination and optical systems with respect to the object.
The illumination system may include a light source (e.g., a fluorescent or incandescent lamp or an array if light emitting diodes (LEDs)). The optical system may include a lens and/or mirror assembly to focus the image of the illuminated scan line onto the surface of the detector. Alternative, a "contact image sensor" (CIS) may be used to collect and focus light from the illuminated scan region onto the detector.
The photosensitive detector used to detect the image light focused thereon by the optical system may be a charge-coupled device (CCD), although other devices may be used. A typical CCD may comprises an array of an individual cells or "pixels", each of which collects or builds-up an electrical charge in response to exposure to light. Since the quantity of the accumulated electrical charge in any given cell or pixel is related to the intensity and duration of the light exposure, a CCD may be used to detect light and dark spots on an image focused thereon.
Referring to FIG. 1A, the reference number 100 is scanning an object; reference number 102 is reflected light which is illuminated the document to form a reflected light; reference number 104 is a conventional lens-imaging device of an optical scanning module; and reference number 106 is an optical sensor. In conventional scanning method of an optical scanner apparatus, a reflected light 102 from the scanning object 100 is transmitted to the lens-imaging device 104 to the optical sensor 106, and an optical imaging (not shown in FIG. 1A) is focused on the optical sensor 106. In the conventional optical scanning module, the imaging data is focused on the optical sensor 106 which is according to the theorem of the formation of image, the reflected light 102 is transmitted from the scanning object 100 to the lens-imaging device 104, the imaging data is communicated to the optical sensor 106. Then, the imaging data is treated and output to the output device, such as a print or monitor (not shown in FIG. 1A).
The response distribution curve diagram of the FIG. 1B is formed that according to the FIG. 1A. According to the theorem of the formation of image, the reflected light point 102A, 102B, and 102C of the scanning object 100 and transmitted to the lens-imaging device 104 to the optical sensor 106 to form a response distribution curve diagram 200. Due to the light dispersion effect, the two ends 202A and 202B of the response distribution curve of the response distribution curve diagram 200 are lower than the response distribution curve that is formed from the light 102C (straight light) and other stream of light (not shown in FIG. 1B) between the ends 202A and 202B. Furthermore, due to the light dispersion effect, the imaging data cannot focus completely on a point such that the resolution of the imaging data on the two ends 202A and 202B is bad. Therefore, the resolution of the scanning object will be degraded.
In addition, the optical scanner apparatus with a lens-imaging device as a formation of image is used for scanning the scanning object 100, the optical image of the scanning object 100 is focused on the optical sensor 106 and converted the analogy signal into digital signal by ADC (analogy digital convert system). Therefore, in order to obtain a higher resolution, the number of pixel for CCD 106 must be increase. However, the cost of the CCD 106 is proportional to the square of the number of pixels. When the higher resolution is required that will cause the cost of CCD 106 is a great part of the production of the optical scanner. Furthermore, the lens-imaging device exhibits a plane to scan the scanning object 100, and the MTF (modulation transfer function) is poor when the optical sensor 106 is diverged from the plane of the lens-imaging device 104.

Optical scanner apparatus with pinhole imaging device


Embodiments herein relate to a method in a radio network node (12,13) for paging a user equipment (10) in a radio communications network (1), which radio network node (12, 13) serves a cell (11) in the radio communications network (1). The radio network node (12, 13) determines whether a condition is fulfilled, which condition is associated with the cell (11). The radio network node (12, 13), when the condition is fulfilled, pages the user equipment (10) in the cell (11).

In a typical radio communications network, wireless terminals, also known as mobile stations and/or user equipments (UE), communicate via a Radio Access Network (RAN) with or via one or more core networks. The radio access network covers a geographical area which is divided into cell areas, with each cell area, or group of cell areas, being served by a base station, e.g., a radio base station (RBS), which in some networks may also be called, for example, a "NodeB" or "eNodeB". A cell is a geographical area where radio coverage is provided by the radio base station at a base station site or an antenna site in case the antenna and the radio base station are not collocated. Each cell is identified by an identity within the local radio area, which is broadcast in the cell. Another identity identifying the cell uniquely in the whole mobile network is also broadcasted in the cell. The base stations communicate over the air interface operating on radio frequencies with the user equipments within range of the base stations.
In some versions of the RAN, several base stations are typically connected, e.g., by landlines or microwave, to a controller node, such as a radio network controller (RNC) or a base station controller (BSC), which supervises and coordinates various activities of the plural base stations connected thereto. The RNCs are typically connected to one or more core networks.
A Universal Mobile Telecommunications System (UMTS) is a third generation mobile communication system, which evolved from the second generation (2G) Global System for Mobile Communications (GSM). The UMTS terrestrial radio access network (UTRAN) is essentially a RAN using wideband code division multiple access (WCDMA) and/or High Speed Packet Access (HSPA) for user equipments. In a forum known as the Third Generation Partnership Project (3GPP), telecommunications suppliers propose and agree upon standards for third generation networks and UTRAN specifically, and investigate enhanced data rate and radio capacity.
Specifications for the Evolved Packet System (EPS) have been completed within the 3rd Generation Partnership Project (3GPP) and this work continues in the coming 3GPP releases. The EPS comprises the Evolved Universal Terrestrial Radio Access Network (E-UTRAN), also known as the Long Term Evolution (LTE) radio access, and the Evolved Packet Core (EPC), also known as System Architecture Evolution (SAE) core network. E-UTRAN/LTE is a variant of a 3GPP radio access technology wherein the radio base station nodes are directly connected to the EPC core network rather than to RNCs. In general, in E-UTRAN/LTE the functions of a RNC are distributed between the radio base stations nodes, e.g., eNodeBs in LTE, and the core network. As such, the RAN of an EPS system has an essentially "flat" architecture comprising radio base station nodes without reporting to RNCs.
Caching concepts, i.e. caching data intended for a user equipment within the radio communications network, are being considered for radio communications networks for the dual purposes of making more efficient use of network resources and improving the end user service experience, e.g. the Quality of Experience (QoE). Sometimes these two goals can be achieved simultaneously, while other times only one of the aspects may be the target. For instance, by delivering requested content from a network cache instead of a remote server, network resources are saved, while at the same time reducing the download delay experienced by the user.
It is not certain where in the network architecture a cache will be placed. It may be integrated in basically any user plane node or be a stand-alone entity in either the radio access network or the Core Network (CN) or it may be deployed above a Gi interface, which is the IP based interface between the Gateway General Packet Radio Service (GPRS) support node (GGSN) and a Public Data Network (PDN) either directly to the Internet or through a Wireless Application Protocol (WAP) gateway, or an SGi interface, which is the interface between the PDN Gateway (PGW). Currently it seems likely that it will be concluded that downlink data from the cache should pass over the Gi/SGi interface. The main rationale for this probable conclusion is that this makes it straightforward to apply core network functions like charging and lawful interception to the data flows.
In the most common uses of caches data is delivered from the cache on request from a client application or device, such as a UE, but caches may also be used to push data to a client application or device or to deliver data based on delivery subscriptions or delay insensitive requests, e.g. to a UE. A problem with the delivery of cached data arises when the network does not know in which cell the user equipment is located. The user equipment needs to be paged in a lot of cells, which may result in waste of resources such as radio resources and user equipment resources.


A device for homogenizing a laser-beam profile and a method for focussing and homogenizing a laser beam in laser photocoagulation for coagulating organic tissue, for example in the eye of a living organism.

A system for laser photocoagulation is known from DE 3936716 A1 and DE 10135944.
A disadvantage of the laser photocoagulators described in the state of the art is that spatial laser-beam profiles with heavy "speckle" occur at the point of impact with the fundus of the eye, which is caused in particular by the inhomogeneous intensity distribution of the transverse mode structure. Inside the laser-beam profile, these inhomogeneities result in significant local thermal elevations (hotspots) during the treatment which far exceed the actual coagulation temperature of approx. 50° C. In standard laser photocoagulation, as a result of the heat conduction into the nerve fibre layer, this leads to a significant increase in pain for the patient and in addition to damage of tissue that is worth preserving.
In addition, because of the spatially inhomogeneous short measurement pulses of a few nanoseconds up to a few microseconds, as a result of the thermal confinement (50 μs), considerable hotspots (>100° C. to 140° C.) occur and thus also cavitation bubbles form inside a light-absorbing tissue layer of the retinal pigment epithelium (RPE).
When these cavitation bubbles collapse, pressure transients form which far exceed the pressure transients, produced by optoacoustics, of the temperature-controlled laser photocoagulation and thus render the actual temperature measurement signal unusable.
An object of the present invention is to overcome the disadvantages known from the state of the art.

Device for homogenizing a laser-beam profile


An external jet nozzle mixer includes identically formed lobes. The external mixer works with the internal mixer further to mix the engine internal bypass flow with the internal jet engine core flow to level the disparate flow velocities, to reduce the peak velocities from the jet engine core and increase the lower bypass velocities of the engine internal bypass flow, and thereby reduce noise. The internal lobe contours act as lifting flutes, causing mixing of the primary hot and cold flows to mix before exiting the nozzle. The external lobe contours act as venturi chutes, accelerating the cooler ambient secondary air flow. The lobes thus act collectively as an injector to force the cooler ambient secondary flow into the previously mixed primary flow as it exits the nozzle. Also obtained is an increased thrust efficiency and, consequently, decreased fuel consumption and engine emissions.

Noise (decibel) level in jet aircraft engines is established by laws and regulations, specifically promulgated by the International Civil Aviation Organization (ICAO), Annex 16. At present, commercial jet aircraft weighing over 75,000 pounds (34,000 kilograms) must meet Stage 3/Chapter 3 noise (decibel) level requirements which establish an allowable decibel noise level. Under Annex 16 Stage 4/Chapter 4 requirements, a lower maximum (decibel) level will be mandated, by at least a reduction of 10 decibels from current Stage 3/Chapter 3 levels. Such noise reduction is effected by mixing of the primary hot exhaust gases in an internal mixer with secondary bypass cooling air and by breaking of the single core of exhaust gases into a plurality of smaller cores through use of a first set of lobes positioned internally in the engine. For some engines, a second set of lobes in an external mixer is positioned downstream from the first set at the terminus of the engine. A thrust reverser module is joined to the engine housing or fan case at the engine terminus by use of an attendant mechanism covered by the STANG fairing. Because the engine has specifically designed dimensions, the second set of lobes must be configured to accommodate the existing engine design, which has a terminus exit area dimension of 1,100 square inches (7,097 square centimeters), rather than to reconfigure the engine to fit the second set of lobes. Such engine reconfiguration is impractical and expensive. Therefore, the direction towards meeting Stage 3/Chapter 3 noise requirements has been involved in developing a variously configured second set of lobes whose design does not always meet such requirements and, when the lobe design does, the lobes are difficult and expensive to manufacture and the mixer is expensive to be retrofitted to the engine. Some engines have not employed the use of a second set of lobes or an external mixer, specifically one produced by Pratt & Whitney, in their JT8D-217/219 Series. Currently, this engine includes an internal 12 lobe mixer and is only certified to Stage 3/Chapter 3 noise levels. There has been a desire to qualify this particular engine to Stage 4/Chapter 4 noise levels, but to minimize the costs of doing so with, preferably, no changes in its thrust reversal components primarily because of cost and other economic reasons. To bring this engine to Stage 4/Chapter 4 noise levels, an additional 2 decibel reduction in jet noise is required. Such an upgrading is a challenge that has not been met.

This patent is subject to a terminal disclaimer.


A method for estimation of relative coordinates between two parts of a linked vehicle system. The system includes a towing vehicle and a towed implement or trailer. A first sensor is configured to measure the movement rate of the towing vehicle while a second sensor is configured to measure the movement rate of the towed implement. Both sensors interact with each other to measure the absolute distance between sensors. Using the known linkage geometry, relative distance between the sensors and relative rotation rates, the relative coordinates between the towing vehicle and towed implement can be estimated.

Farm equipment, known as implements, may be used for various agricultural tasks, such as tilling, planting seeds, spreading fertilizer, harvesting, or other similar tasks. Such tasks are typically performed by towing the implement with a towing vehicle, such as a tractor, over swaths of a field until the entire field is covered. To optimize time and minimize costs, these tasks are best performed in a fashion that either eliminates or keeps overlap between swaths to a minimum. This requires accuracy in controlling the implement. The process of guiding a towed implement or trailer accurately on a desired path via maneuvering the towing vehicle, such as a tractor, requires knowledge of the towed implement's position and orientation relative to the path. For conventionally controlled vehicles, e.g. tractors that are manned and driven by an operator, the tractor's or other towing vehicle's operator may rely upon mirrors and direct visual observation, combined with operational experience, to correctly control the vehicle so that the towed implement is guided along the desired path.
With their increasing maturity and availability, computer assisted and autonomous driving systems may be deployed to either assist or fully control vehicles that may be towing an implement, such as a tractor and coupled farm implement. These systems, moreover, may be able to exercise a level of precision control in maneuvering a towing vehicle that is difficult, if not impossible, for a human operator to achieve. Where a towed implement is used to complete a task, precision positioning of the implement with respect to an intended path may be critical. As the path traveled by the implement may depend upon the path of the towing vehicle, accurate implement control via a computer-assisted or autonomous driving (CA/AD) system requires position and orientation information of not only the vehicle, but also the implement. Knowledge of the position of the implement may enable the CA/AD system to guide the towing vehicle/tractor so that the implement follows a prescribed path.


A semiconductor memory device includes a plurality of memory cell transistors arranged in a matrix; a plurality of word lines commonly coupling the control gates of the plural memory cell transistors present in a identical first direction; a plurality of source lines commonly coupling the sources of the plural memory cell transistors present in the identical first direction; a plurality of bit lines commonly coupling the drains of the plural memory cell transistors present in a identical second direction intersecting the first direction; a first transistor having a drain coupled to the source line; a second transistor having a drain coupled to a source of the first transistor, a gate coupled to the word line and a source grounded; and a control line commonly coupling the gates of the plural first transistors.

As a rewritable nonvolatile semiconductor memory device is known the flash memory, which stores charges in charge storage layers, such as the floating gates, etc. of the memory cell transistors to thereby store information. In the flash memory, information is written by injecting charges into the floating gates, etc., and information is erased by ejecting charges stored in the floating gates, etc. In the N-type memory cell transistors, when negative charges (electrons) are injected, their threshold voltage Vt becomes high, and when stored electrons are ejected, their threshold voltage Vt becomes low. Binary information is stored by the written state of the memory cell transistors, in which the threshold voltage Vt is high and the erased state thereof in which the threshold voltage Vt is low.
As flash memories are known NOR type, NAND type, etc. depending on their internal basic circuit structures. In the NOR flash memory, a plurality of memory cell transistors MT, which are present in the identical column are connected to a common bit line BL.

Semiconductor memory device and method for driving semiconductor memory device


Power usage of computing device components is controlled in a holistic manner. The projected total power consumption for the computing device to satisfy a power consumption policy for the device is determined. Power usage of each component of the computing device is controlled in a holistic manner—i.e., balancing the power usage of the component against the power usage of other components—so that the total power usage of the computing device falls within the projected total power consumption needed to satisfy the power consumption policy. How the user is currently utilizing the computing device may be periodically detected, based at least on a power consumption distribution of the components of the computing device. A current usage model is determined based on how the user is currently utilizing the computing device. The power usage of each component of the computing device is controlled based on the current usage model.

Typical portable computing devices include laptop and notebook computers and other portable computers. Unlike desktop computers, which must be constantly plugged into a wall outlet to receive power so that they can be used, portable computers include batteries so that users can use them while away from a wall outlet, such as on planes and trains, in conference rooms and so on. The batteries are rechargeable, so when they lose their power through usage of the portable computers, the computers can be plugged into a wall outlet to recharge their batteries.
Portable computers have become nearly as popular as desktop computers. The performance of portable computers has also increased to rival many desktop computers. The processing power of portable computers, their screen sizes, graphics chips, available memory, and available storage are nearly equal to that found in desktop computers. Indeed, one type of portable computer is known as the "desktop replacement," which is intended to replace a typical desktop computer. Such portable computers usually include an optical drive, and can have a wide variety of peripherals attached to them.
Unfortunately, battery technology has not increased at the same pace as other technologies used in portable computers. Therefore, how long a portable computer can run on battery power is an issue that pervades design choices in which technologies to use in portable computers. Furthermore, users have become adept at monitoring power usage within portable computers. Users may have to adjust how they use their computers to ensure that the battery charge lasts as long as is needed.
Present battery management technologies are limited, however. Major components of a portable computer can individually perform power management. For example, the central processing unit (CPU) and the graphics processor of a portable computer may be able to have their operating frequencies reduced to limit power usage. Such individual power management is typically effective, however, only if the other components of a portable computer are also not consuming large amounts of power.
Other battery management technologies include reducing the backlight for the display of a portable computer based on the amount of power remaining in the battery. However, in all of these battery management technologies, power management is not based on the load of all the components of a portable computer as a whole. Therefore, while they are effective to some degree, they still do not optimally manage the remaining power of a battery within a portable computer.
One type of power management technique is particularly described in U.S. Pat. No. 6,289,399. In this patent, a computing device determines how the computer is currently being utilized by directly monitoring the load on the processor (i.e., the CPU), as well as the frequency of input/output (I/O) access, such as access to hard disk drives. Based on how the computer is currently being utilized, power can then be conserved appropriately. However, this approach has some disadvantages. First, it does not correctly determine how the computer is being used when there is a light load on the processor. Second, it does not correctly determine how the computer is being used when there is a load on another type of device that the user is currently using, such as a graphics or video chip, or memory. Third, if the sampling rate of monitoring the frequency of I/O access is too infrequent, then the approach may not correctly determine how the computer is currently being used. At the same time however, fourth, if the sampling rate of monitoring the frequency of I/O access is too frequent, then the approach itself may cause an undue load on resources of the computing device.
For these and other reasons, then, there is a need for the present invention.

Controlling power usage of computing device components in holistic manner


A load warning system for use with a vehicle having a load-support portion, a frame, and a vehicle-support portion movably coupled to the frame. The system has an engagement portion mountable to the vehicle-support portion or the frame and is movable therewith as a unit. A load indicator is mountable to the other one of the vehicle-support portion or the frame, and is spaced apart from the engagement portion when in a first position. The load indicator moves to a second position and engages the engagement portion when the frame moves a selected distance in response to the load applied to the load-support portion. The load indicator provides a signal upon being moved to the second position. A warning indicator is coupled to the load indicator and provides an improper load warning to a user in response to the signal from the load indicator.

Vehicles, such as trucks, typically have maximum load ratings set by the vehicle manufacturer. Many vehicles have payload areas that can be loaded with a payload that could exceed the maximum load rating. The payload areas can also be improperly loaded with a payload even though the payload doesn't exceed the maximum load rating for the vehicle. For example, a payload below the maximum load rating could be located too far to one side or too far to the rear, thereby changing the handling or steering characteristics of the vehicle. It is highly desirable to provide a warning system that indicates when a vehicle is improperly loaded.
Prior systems have been designed to accurately measure the payload weight or axle weight. Most of these systems use load cells to support the weight and provide an electrical signal indicative of the weight. Some systems have relied on the deflection of the vehicle's suspension to provide an indication of load. As an example, U.S. Pat. No. 3,531,766 to Henzel discloses such a sensing system for overload indication. U.S. Pat. Nos. 4,789,033; 5,522,468; and 6,259,041 B1 to Dohrmann show various systems that translate suspension travel into motion that can be measured. The sensor output is sent to a display unit that gives an indication of weight. These prior art systems, while detecting weight, have limitations in determining or detecting improper load conditions in a vehicle.


The invention involves a system and method for increasing positional accuracy of surgical systems that utilize magnetic or electromagnetic sensors to provide positional awareness to a surgeon or robot performing the surgery. The system takes advantage of electromagnetic tracking through sensors. These sensors are very accurate and repeatable, while being compact enough to not inhibit surgical procedures. The accuracy and repeatability of the sensors is <1 mm within a predetermined 6 inch×6 inch performance motion box. The system is constructed and arranged to map the distortion patterns of the sensor and, in real time, correct the distortion pattern to provide accurate location of anatomical structures for performance of a surgery.

Robotic surgery, computer-assisted surgery, and robotically-assisted surgery are terms for technological developments that use robotic systems to aid in surgical procedures. Robotically-assisted surgery was developed to overcome the limitations of pre-existing minimally-invasive surgical procedures and to enhance the capabilities of surgeons performing open surgery.
In the case of robotically-assisted minimally-invasive surgery, instead of directly moving the instruments, the surgeon uses one of two methods to control the instruments; either a direct telemanipulator or through computer control. A telemanipulator is a remote manipulator that allows the surgeon to perform the normal movements associated with the surgery while the robotic arms carry out those movements using end-effectors and manipulators to perform the actual surgery on the patient. In computer-controlled systems, the surgeon uses a computer to control the robotic arms and its end-effectors, though these systems can also still use telemanipulators for their input. One advantage of using the computerized method is that the surgeon does not have to be present, but can be anywhere in the world, leading to the possibility for remote surgery. One drawback of these systems relates to interference in the sensors that monitor the location of the robotic components, including the tools being used by the robot to complete the surgery. Surgical tools, and even robotic components, are often constructed from materials that are not radio translucent, and thus they cause interference with the sensors used to guide the robot to its desired precise location. The interference may cause the robot to not be located where it should be, and may cause problems with the surgery.
In the case of enhanced open surgery, autonomous instruments (in familiar configurations) replace traditional surgical tools, performing certain actions (such as rib spreading) with much smoother, feedback-controlled motions than could be achieved by a human hand. The main object of such smart instruments is to reduce or eliminate the tissue trauma traditionally associated with open surgery. This approach seeks to improve open surgeries, particularly orthopedic, that have so far not benefited from robotic techniques by providing a tool that can provide precise location of the tool with respect to anatomical markers when the robot or tool causes interference with the sensors used to provide that location.
One major drawback to electromagnetic sensors that can be used to provide positioning to robots for surgical procedures is their vulnerability to distortion. Materials with electromagnetic signatures impact the magnetic field which is generated by the NDI transmitter. This impact causes distortions in the sensor frame, which leads to incorrect position and orientation reporting.
There exists, therefore, a need for a robotic system that is capable of reducing or eliminating electrical and/or magnetic interference from tool and robot positioning to provide better positional accuracy.
Thus, the present invention provides a system and method for reducing distortion or interference during robotic or sensor enhanced manual surgery which overcomes the disadvantages of prior art systems.

System and method for reducing interference in positional sensors for robotic surgery


Disclosed is a mechanical swirler for generating diverging flow in lean premixed fuel burners. The swirler of the present invention includes a central passage with an entrance for accepting a feed gas, a flow balancing insert that introduces additional pressure drop beyond that occurring in the central passage in the absence of the flow balancing insert, and an exit aligned to direct the feed gas into a combustor. The swirler also has an annular passage about the central passage and including one or more vanes oriented to impart angular momentum to feed gas exiting the annular passage. The diverging flow generated by the swirler stabilizes lean combustion thus allowing for lower production of pollutants, particularly oxides of nitrogen.

Combustion is a major source of pollutants. One class of pollutants, oxides of nitrogen, or NO.sub.x, (NO or nitric oxide, NO.sub.2 or nitrogen dioxide, and N.sub.2 O or nitrous oxide) contribute to acid rain, smog, global warming, and ozone depletion. As NO.sub.x emissions from combustion sources primarily consist of nitric oxide, an understanding of how NO is generated is important. There are three principal mechanisms which produce NO during combustion: 1) the fuel NO mechanism; 2) prompt NO mechanisms; and 3) the Zeldovich mechanism, also known as "thermal NO". As "fuel NO" is produced via oxidation of nitrogen contained with the fuel, it is not generally an issue for combustion sources using gaseous fuels as these contain little, if any nitrogen compounds. The majority of "prompt NO" is formed through three paths with the significance of each path dependent upon a multiplicity of variables such as pressure, fuel/air ratio, temperature, and concentrations of other compounds. "Thermal NO" is formed by the oxidation of atmospheric nitrogen, N.sub.2, and increases exponentially with combustion temperature. In most combustion applications, the majority of NO, and thus NO.sub.x in general, is produced by the "thermal NO" mechanism, with "prompt" and other mechanisms playing a minor role. As such, combustion processes which decrease the combustion temperature, and thus greatly reduce the production of thermal NO, can have a large effect on the entire production of NO.sub.x. Further information on this subject may be found in Bowman, C. "Control of Combustion-Generated Nitrogen Oxide Emissions: Technology Driven By Regulation", Twenty-Fourth Symposium (International) on Combustion, The Combustion Institute 1992, pp. 859-878, which is incorporated by reference herein.
The best strategy to control pollution is to minimize its formation at the combustion source. Current research and development efforts are mainly dedicated to lowering emissions through re-engineering of conventional non-premixed combustion systems. Non-premixed combustion is the scientific term given to the combustion process where fuel and oxidizer (usually air) mix and burn concurrently. Non-premixed flames are not clean. Unmitigated, they generally emit unacceptable levels of oxides of nitrogen (NO.sub.x) of over 200 parts-per-million (ppm), substantially higher than regulations allow for certain applications. The heating and power generation industries have recognized the need to develop premixed combustion systems as they are much cleaner than non-premixed combustion systems. In premixed combustion systems, as its name implies, gaseous fuel and oxidizer (usually air) are first mixed and then burned. It is desirable to separate the mixing and burning processes, as the user can then control the fuel-to-air ratio being delivered to the reaction zone. The major challenge facing research and development of premixed combustion systems is that the body of knowledge gained from conventional (i.e. non-premixed) burner development is not directly transferable to premixed systems due to differences in flame dynamics.
A burner requires a stable flame. For non-premixed burners, maintaining a stable flame in the zone where the fuel and air are mixing together is the important design criterion. On the other hand, the design of premixed burners have quite different requirements as the mixing occurs separately from the burning processes. Also, when burning the premixed fuel and air mixture (or "feed gas") the flame front propagates through the feed gas. In contrast, non-premixed flames do not propagate. The speed at which a premixed flame propagates through the mixture is called the flame speed. Flame speed is a function of the fuel/air equivalence ratio and turbulence intensities. A fundamental requirement of premixed burners is that the velocity of the premixed feed gas in the burner has to be greater than the flame speed. Otherwise, the flame will propagate upstream against the premixed feed gas stream and into the body of the burner. This condition is termed "flash-back," and must be avoided. To maintain a stable flame, an obstacle may be placed in the premixed feed gas to `anchor` the flame. The size of the flame anchor (also called a "flame-stabilizer" or "bluff-body") and their aerodynamic shapes can be optimized for given operating ranges and burner considerations. Although these anchors can help to prevent flash-back, a flame can become unstable and "blow-off" the anchor if the velocities are too high. This is particularly true for lean flames, as they tend to blow-off easily due to the excess air in the feed gas. The challenge for premixed burners which support lean flame conditions, is to have a design robust enough to eliminate both flash-back and blow-off occurrences.
Conventionally, stable premixed feed gas flames have been achieved by using a flame anchor, as described above. The obstruction generates a zone of zero axial flow on its upstream side and turbulent flow on its downstream side. As the fuel flows around the obstruction, it becomes turbulent and several regions of reverse flow are created where the fuel flow is actually circling back in a direction opposite to the original flow. This pattern, referred to as "recirculation," is relatively stable and prevents blowout when burner operating conditions are appropriately set.
Swirling flows have also been used to stabilize combustion in a variety of burners, both premixed and non-premixed. Swirl in these burners is generally created either by generating tangential flow motion in a cylindrical chamber, as in cyclone combustion chambers, or swirling a co-axial air flow. In both cases, the function of the swirl is to create a torroidal recirculation zone (TRZ). For non-premixed combustion, the role of the TRZ is to mix the fuel and air to allow for complete combustion, to stabilize the combustion process, to recirculate some fraction of the products, and to dictate the physical shape and length of the flame in these burners. In premixed burners, the TRZ created by the strong swirl creates a zone where the combustion zone is "anchored" due to an area of low flow velocities found within the TRZ.
Many attempts have been made to reduce NO.sub.x emissions from combustion sources in hopes of reducing the air pollution associated with the burning of hydrocarbon fuels. Pollution reduction methods generally fall into two categories. One category of reduction methods involve post-combustion remediation technologies, such as Selective Catalytic Reduction (SCR) or Selective Non-Catalytic Reduction (SNCR), to reduce pollution after it has been generated in the combustion zone. Combustion modifications through burner design changes, such as burning lean, fuel-air staging, or flue gas recirculation, can reduce pollutant formation in the reaction zone. These methods constitute the second category of pollution reduction technologies. Taking into account tradeoffs with engineering considerations and other pollutants, low NO.sub.x burners generally burn with as much excess air (i.e. "lean") as possible, as this will reduce combustion temperatures and minimize thermal NO.sub.x production. Some NO.sub.x may still be produced by virtue of the prompt NO.sub.x mechanisms detailed earlier.
U.S. Pat. No. 4,021,188 to Yamagishi et al. ("the '188 patent") describes various non-premixed burner arrangements using both staged combustion and exhaust gas recirculation to decrease the production of NO.sub.x during combustion of hydrocarbon fuels and air. Staged combustion involves an initial combustion of a fuel rich-air mixture followed by a second combustion zone of the partially combusted fuel exhausted from the first reaction zone, generally in combination with a secondary air supply. The burner configurations disclosed in the '188 patent involve a fuel-rich, first combustion stage followed by a fuel-lean, low-temperature second combustion stage. Several of these configurations involve a swirling mechanism to mix the partially combusted gas discharged from the first combustion stage with a secondary air source. This swirling fuel-air mixture undergoes a second combustion stage at a lower combustion temperature than that of the first stage. The '188 patent discloses a number of apparatuses equipped with a swirling mechanism, such as blades or slits, to induce a rotating flow in the partially combusted gas discharged from the first combustion stage or in the secondary air supply.
In all of these apparatuses, the air component of the fuel-air mixture is supplied to the secondary combustion zone through a separate passage from a separate source from that of the partially combusted gas, which proceeds to the secondary combustion zone through a central passage that is either unobstructed or contains a central hub. The '188 patent also discloses that the partially combusted gas is cooled by a flow which develops as surrounding relatively low temperature combustion gas is attracted into the center of the rotating flow of the partial combustion gas, thereby inhibiting NO.sub.x formation from thermal NO.sub.x production. Thus, these apparatuses rely upon torroidal recirculation for flame stabilization.
For premixed combustion, another design has achieved a significant reduction in NO.sub.x production using single stage combustion without recirculation. U.S. patent application Ser. No. 08/033,878, filed Mar. 19, 1993 ("the '878 application), which is the parent of the present application, and has been previously incorporated by reference into the present application, discloses a lean premixed burner which generates a stable flame by swirling the edges of a thoroughly mixed fuel-air mixture without inducing recirculation. Unlike many conventional burners, including the second stage of the burners disclosed in the '188 patent, in which the fuel and air are mixed in the combustion zone, the '878 application discloses a premixed fuel-air mixture that is swirled gently by low swirl jets of air, or premixed fuel/air, introduced tangentially to the premixed stream of feed gas upstream of the reaction zone. The low swirl creates a divergent flow pattern that "anchors" the flame at the point where the flame speed balances the mass flow rate of the fuel-air mixture, thus stabilizing the flame zone without the use of recirculation.
A common parameter for characterizing the swirl intensity of swirl burners is in use throughout the combustion industry. The non-dimensional swirl number, S, is defined as the ratio of axial flux of angular momentum to the axial flux of linear momentum divided by the nozzle radius: ##EQU1## where R is the nozzle radius, and U and W are the mean axial and tangential components of the flow velocity within the swirl generator, respectively.
For a tangential air injection swirler, this integral form is commonly approximated by the following geometric form: ##EQU2## where r.sub..theta. is the radius of the swirl jets, A.sub..theta. is the total area of the jets, m.sub..theta. is the total tangential mass flow, and m.sub.a is the total axial mass flow.
For a conventional hub vane-swirler design without flow through the central hub, the swirl number equation (1) reduces to: ##EQU3## where R.sub.h is the radius of the central hub, .alpha. is the vane angle from the vertical axis, and U is uniform over the tube cross section. The conventional hub vane-swirler was designed for non-premixed combustion in which the central hub acts as a bluff-body and generates a torroidal recirculation zone. TRZs are formed only when there is a high degree of swirl in the flow field, that is, where S.gtoreq.approximately 0.6.
The swirl requirement of a weak-swirl burner (WSB) is different from that of other burners since the feed gas is premixed and flame stabilization is achieved through use of a divergent flow field instead of a TRZ. Due to the propagating nature of pre-mixed flames and the deceleration of the flow as it moves away from its source, the flame is able to dynamically stabilize itself at the position where the local mass flow rate balances the flame propagation speed. The weak-swirl stabilization mechanism does not apply to diffusion flames (not pre-mixed) because they do not propagate, but rather burn at the boundary where the air and fuel flows have diffused to the appropriate ratios for sustaining the combustion reaction.
The air-swirled weak-swirl burners disclosed in the '878 application are well suited for those applications where compressed air is readily available and currently used, such as in boilers and industrial furnaces. However, air injection may be impractical or uneconomical (due the necessary compressor and controls) for some high volume, low margin consumer products, for example, water heaters. Therefore, it would be highly desirable to replicate the benefits of the low NO.sub.x emission weak swirl burner of the '878 application with alternative designs, particularly if those designs were easily adaptable to a broad range of applications and were relatively simple and economical to scale, manufacture and operate.
Accordingly, there is a need for alternative designs for weak-swirl burners.

Mechanical swirler for a low-NO.sub.x, weak-swirl burner

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