The apparatus is a detector for ferromagnetic objects using a small passive coil to sense disturbances in the earth's magnetic field when an object moves near the coil. The circuit uses a multiplier in the form of an electronic switch on the output of the coil to impose a much higher frequency on the output of the coil. This separates the frequency of amplification from the frequency of the coil signal and makes it possible to sharply filter the signal, prevent false alarms from electrical noise, identify the direction in which the object is moving, and reduce the power consumed through the use of a sampling technique. The frequency conversion technique also allows for multiplexing of multiple coils by one signal processing circuit.

This invention deals generally with condition responsive indicating systems based on disturbances of magnetic fields and more specifically with ferromagnetic object detectors such as vehicle detectors.
Use of the earth's magnetic field as a basis for detection of ferromagnetic objects such as vehicles is not new. U.S. Pat. No. 3,237,155 to Brockett discloses such a system which is typical of many prior art devices that use an amplifier operating at the base band frequency of the signal input along with classical frequency filtering to attempt to overcome the several sources of electrical noise which can affect such a circuit.
The input signal for such devices is generated by the distortion of the earth's magnetic field which occurs when a large ferromagnetic object such as a vehicle moves within the magnetic field. The vehicle actually bends the magnetic lines of force near it as it concentrates those lines into its ferromagnetic body. This distortion moves along with the vehicle and can best be envisioned as an electromagnetic wave motion which causes a changing magnetic field in any location as the vehicle approaches and departs from the location. A coil of wire located in such a region with a changing magnetic field has a current generated in it and a corresponding voltage developed across it in accordance with the laws of electromagnetic induction.
The important characteristics of the currents generated in a passive sensing coil by the motion of a vehicle through the earth's magnetic field are that the voltages are very low frequency and very low amplitude, and these are the factors which have made prior art vehicle detector circuits unreliable. Weak signals are always subject to problems with extraneous electrical noise. Such noise may be internally generated by the circuit components themselves or from external sources such as power lines, lightning, and radio frequency generators, and even though band pass frequency filters have traditionally been used in vehicle detection circuits, such electrical noise can actually enter the circuits, or be generated within them, at locations throughout the band pass filter and amplifier stages.
The noise problem is made more difficult by the very low frequency generated by the magnetic sensing coils. The typical input frequency for vehicle detection circuits is between 0.1 Hz and 5 Hz, and the typical amplifiers used for such circuits are band pass amplifiers operated at the base band frequency of the sensing coil output and having a practical bandwidth of 0.5 Hz to 5.0 Hz. The lower end frequency of such amplifiers is limited because the overwhelming effects of low frequency noise and temperature drift generated within the circuit components have increasing effect below 1 Hz. Also internally present within the circuits are spurious noise transients, and all these noise and drift factors combine with externally generated noise. The base band approach also has problems in that all these noise components manifest themselves in oscillation or "ringing" of the band pass amplifiers at the base band frequency. Since this frequency is similar to that produced by the sensing coil, it becomes extremely difficult to distinguish such noise generated false signals from true detection.
Since such low frequency amplifiers are AC coupled, they require very large capacitors which also add to the noise problems because of internal leakage. Another problem is that the physical size of the circuits can not be reduced below the substantial size of the capacitors. A more subtle difficulty encountered due to the large capacitors is slow amplifier power up times, because of the charging times required for such large capacitors. This means that the amplifiers must be left on continuously which results in high power consumption. An unsatisfactory compromise is to reduce the size of the capacitors by discarding the lowest of the frequencies generated by the magnetic coil sensor.

Preferred Security Components, Inc of PA


To realize simplification of a process of forming hollow portions in a solid-state imaging apparatus, a plurality of light receiving portions is formed on a semiconductor substrate, and color filter layers as hollow portion forming layers are formed above the semiconductor substrate (FIG. 1A). A sealable layer for opening boundary portions of the color filter layers is formed on the color filter layers (FIG. 1B). Hollow portions are formed on side surfaces of the color filter layer by etching using the sealable layer as a mask (FIG. 1C). The sealable layer is heated and softened to connect mutually adjacent sealable layers to form a sealing layer for sealing the aperture regions of the hollow portions (FIG. 1D).

1. Field of the Invention
The present invention relates to a manufacturing method of a solid-state imaging apparatus (solid-state imaging device) such as a CCD sensor and a CMOS sensor.
2. Description of the Related Art
A technique for improving the light collecting efficiency of receiving portions, particularly, a technique of more efficiently collecting light with a steep incident angle, is desired in a solid-state imaging apparatus. For example, a solid-state imaging apparatus is proposed in recent years, wherein hollow portions are formed in regions equivalent to the surrounding of the light receiving portions, and reflection of hollow portion interfaces is used to improve the light collecting efficiency of the light receiving portions (for example, Japanese Patent Application Laid-Open No. 2010-199258).
Specifically, Japanese Patent Application Laid-Open No. 2010-199258 describes the formation of the hollow portions, wherein a resist for opening hollow portion forming regions is formed on an insulation layer in which the hollow portions are formed, and aperture portions are formed on the insulation layer by dry etching using the resist as a mask. After the resist is removed, a protective film is formed on the insulation layer to seal the aperture portions by the protective film to form the hollow portions.
However, the method of Japanese Patent Application Laid-Open No. 2010-199258 has a problem that the formation process of the hollow portions is complicated.
The present invention has been made in view of the problem, and an object of the present invention is to provide a manufacturing method of a solid-state imaging apparatus that realizes simplification of a process of forming hollow portions in the solid-state imaging apparatus.

Manufacturing method of solid-state imaging apparatus


A magnetic domain wall motion memory according to an embodiment includes: a magnetic memory nanowire; a write magnetic wire intersecting with the magnetic memory nanowire; an intermediate joining portion provided in an intersection region between the write magnetic wire and the magnetic memory nanowire; adjacent pinning portions placed on one of the same side and the opposite side of the write magnetic wire as and from the magnetic memory nanowire; a read unit attached to the magnetic memory nanowire; a pair of first electrodes that applies a write current to the write magnetic wire; and a pair of second electrodes that applies a current for causing the magnetic memory nanowire to move a magnetic domain wall, wherein contact faces of the write magnetic wire in contact with the adjacent pinning portions have magnetization configurations antiparallel to each other.

In recent years, there have been reports that magnetic domain walls driven by a current were observed in magnetic nanowires having submicron widths. Magnetic domain wall motion memories that are capable of moving magnetic domain walls by utilizing this effect have been suggested. In such a magnetic domain wall motion memory, magnetic nanowires (magnetic memory nanowires) each divided into magnetic domains are used, and information (data) "0" or "1" corresponding to the magnetization directions of the magnetic domain walls is stored. Since the magnetic domains move as the magnetic domain walls move when a current is applied, the information (data) stored in the magnetic domains also moves. Accordingly, the information can be read with a stationary sensor, and can be written with a stationary write unit. That is, the magnetic domain walls are equivalent to memory cells.
In general, there is an increasing demand for magnetic memories having larger capacities with higher cell densities, and there is also an increasing demand for reductions in power consumption.
Specific examples of write methods for the magnetic domain wall motion memories include: a write method utilizing a magnetic field that is generated around a wire different from the magnetic memory nanowires by applying a current to the different wire; a method of writing with spin transfer torque by utilizing magnetic tunnel junctions formed in some of the magnetic memory nanowires; and a write method by which a pair of pinning portions having opposite magnetization directions are provided for each magnetic memory nanowire and are located in the same plane as the magnetic memory nanowires, and magnetic domain walls are moved by applying a current to wires provided for the respective pinning portions. However, these write methods have yet to overcome the difficulties in lowering power consumption and increasing capacities. Therefore, there is still a demand for reductions in power consumption and writing with larger capacities.

Magnetic domain wall motion memory and write method for the same


Methods and apparatus are provided for receiving packets on a channel of an Orthogonal Frequency Division Multiplexing (OFDM) system. A time shift value for a packet is estimated using a channel estimation and an FFT size. A synchronization position of the packet on a channel is adjusted using the estimated time shift value, and a filter is applied to the adjusted channel to generate a smoothed channel estimate. Alternatively, a channel with a corrected packet synchronization position is estimated, and a smoothed channel is estimated by applying a filter to the estimated channel. Packets are received on the channel, at a receiver of the OFDM receiving apparatus, in accordance with the estimated smoothed channel.

1. Field of the Invention
The present invention relates generally to channel estimation in an Orthogonal Frequency Division Multiplexing (OFDM) receiving apparatus, and more particularly, to providing a robust synchronization position adjustment algorithm to improve channel estimation in an OFDM receiving apparatus.
2. Description of the Related Art
FIG. 1 is a diagram illustrating an OFDM system, which includes an OFDM transmitting apparatus 102 and an OFDM receiving apparatus 110. The OFDM transmitting apparatus 102 receives data for modulation in a modulation unit 104. The modulated data is provided to an Inverse Fast Fourier Transform (IFFT) unit 106 and then a digital to analog conversion unit 108. A baseband OFDM signal is then transmitted from the OFDM transmitting apparatus 104. The baseband OFDM signal is received at an analog to digital conversion unit 112 of the OFDM receiving apparatus 110 and then provided to a Fast Fourier Transform (FFT) unit 114 before demodulation in a demodulation unit 116. Data is then output from the demodulation unit 116 of the OFDM receiving apparatus 110.
Accurate channel estimation is a crucial factor in the performance of a Physical (PHY) layer in an OFDM system. Channel estimation is typically performed between FFT and demodulation in the OFDM receiving apparatus. A channel may be estimated with training field preambles, such as, for example, Legacy Long Training Field (L_LTF), High Throughput Long Training Field (HT_LTF), and Very High Throughput Long Training Field (VHT_LTF) in Institute of Electrical and Electronics Engineers (IEEE) 802.11a/g, IEEE 802.11n, and IEEE 802.11ac, respectively. Zero forcing is an algorithm that is commonly adopted to estimate channel response along all used subcarriers. Zero forcing channel estimation does not exploit coherence among neighboring subcarriers, which increases estimation errors, especially when white Gaussian noise is presented.
In Jan-Jaap Van De Beek et al., "On Channel Estimation in OFDM System," Proceedings of the IEEE Vehicular Technology Conference, July 1995, pp. 815-819, a Minimum Mean Square Error (MMSE) algorithm is proposed to obtain optimal linear estimation by exploiting the correlation between subcarriers. However, this solution is impractical to implement in hardware due to its high complexity.
Attempts to obtain suboptimal solutions have also been made, such as in Darryn Lowe and Xiaojing Huang, "Adaptive Low-Complexity MMSE Channel Estimation for OFDM," 2006 International Symposium on Communications and Information Technologies (ISCIT), Bangkok, Thailand, 18-20 Oct. 2006, and Hsuan Yu Liu et al., "Combining Adaptive Smoothing and Decision-Directed Channel Estimation Schemes for OFDM WLAN Systems," Proceedings of the 2003 International Symposium on Circuits and Systems, pp. 149-152. However, these proposals assume an ideal synchronization position for a packet, which is very difficult to achieve, especially in fading channel or multiple transmitter scenarios due to the well-known pseudo-multipath problem, even though some attempts have been made to improve it. See, e.g., U.S. patent application Ser. No. 12/617,537, filed Nov. 12, 2009.
Although current synchronization in an OFDM wireless Local Area Network (LAN) cannot accurately detect the exact start of each symbol of an OFDM packet, this may not cause a serious problem due to the existence of a guard interval. A packet offset is introduced to start FFT data sampling within the guard interval to mitigate the effects of an inaccurate sync position. However, when there is an error in synchronization, the channel will no longer be flat for an Additive White Gaussian Noise (AWGN) channel, as both the real and imaginary parts will display sinusoidal oscillation. Applying a smoothing filter, which is not optimal for such synchronization error, to such an oscillating channel can introduce distortion. The above-described phenomenon becomes even more serious for a multiple transmitter antennas scenario due to synchronization uncertainty from the pseudo-multipath phenomenon caused by cyclic shift.

Method and apparatus for channel smoothing and estimation in OFDM system


An all-wheel-drive electric vehicle includes one or more front electric motors, one or more rear electric motors, an accelerator sensor, a vehicle speed sensor, and a control unit. The one or more front electric motors are configured to directly drive front wheels. The one or more rear electric motors are configured to directly drive rear wheels. The accelerator sensor is configured to determine an operation amount of an accelerator. The vehicle speed sensor is configured to determine vehicle speed. The control unit is configured to control drive of the one or more front and rear electric motors based on the operation amount of the accelerator and the vehicle speed. The control unit is configured to change an allocation of driving force between the one or more front electric motors and the one or more rear electric motors with a bias toward the rear wheels in a case where the operation amount of the accelerator is increased at or above a predetermined rate in a state in which the vehicle speed is higher than or equal to a predetermined speed.

The disclosure relates to an all-wheel-drive electric vehicle.
Recently, electric vehicles (EVs) powered by electric motors and not emitting exhaust gas are in practical use. For example, such an all-wheel-drive electric vehicle includes a front motor that drives front wheels and a rear motor that drives rear wheels.
Interior permanent magnet (IPM) motors that are compact and operate with a high degree of efficiency are suitably included in such an EV. For example, an IPM motor disclosed in Japanese Unexamined Patent Application Publication No. 2012-105482 includes a rotor incorporating magnets fitted inside an iron core. With a permanent magnet embedded in the rotor, such an IPM motor is suitable for high-speed rotation. The IPM motor can use reluctance torque that acts on a magnetic circuit in such a way as to attract and repel part (projections) of a yoke. The reluctance torque is combined with magnet torque resulting from attraction and repulsion between the permanent magnet and a coil. This enables the IPM motor to produce high output torque.


According to the present invention, a data processing system includes a cache having a cache directory. A status indication indicative of the status of at least one of a plurality of data entries in the cache is stored in the cache directory. In response to receipt of a cache operation request, a determination is made whether to update the status indication. In response to the determination that the status indication is to be updated, the status indication is copied into a shadow register and updated. The status indication is then written back into the cache directory at a later time. The shadow register thus serves as a virtual cache controller queue that dynamically mimics a cache directory entry without functional latency.

1. Technical Field:
The present invention relates in general to an improved method and system for data processing. In particular, the present invention relates to an improved method and system for data communication in a data processing system and an improved method and system for cache management in a data processing system.
2. Description of the Related Art:
A conventional symmetric multiprocessor data processing system may include a number of processors that are each coupled to a shared system bus. Each processor may include an on-board cache that provides local storage for instructions and data, execution circuitry for executing instructions, and a bus interface unit (BIU) that supports communication across the shared system bus according to a predetermined bus communication protocol.
In conventional multiprocessor data processing systems, each BIU maintains a single queue of all outstanding communication requests generated within the processor. The communication requests indicate a request address and a request source within the processor. To promote maximum utilization of the system bus, the BIUs typically service the communication requests utilizing split bus transactions, which permit multiple bus transactions to be chronologically interleaved. For example, the BIU of a first processor may gain ownership of the system bus and initiate a first bus transaction by driving an address and appropriate control signals. The first processor may then relinquish ownership of the system bus while awaiting receipt of data associated with the address in order to permit a second processor to perform a portion of a second bus transaction. Thereafter, the device from which the first processor requested data may complete the first bus transaction by driving the requested data, which is then latched by the BIU of the first processor. To allow devices snooping the system bus to identify the bus transaction to which each transaction portion belongs, each BIU assigns each of its bus transactions an arbitrary bus tag that is transmitted during each tenure of the bus transaction. The bus tags are typically assigned cyclically out of a pool of bus tags equal in number to the maximum number of concurrent bus transactions supported by the device. For example, the BIU of a device supporting a maximum of eight concurrent bus transactions assigns one of eight low order 3-bit tags to each of its bus transactions The bus tags are stored by the device in association with the appropriate queue entries.
Although employing split bus transactions tends to maximize bus utilization, supporting split bus transactions concomitantly increases device complexity due to the allocation logic required to dynamically allocate and deallocate bus tags and the. associative logic utilized to determine which bus transaction is associated with each snooped bus tag. In addition, decoding each bus tag prior to routing retrieved data to the appropriate request source within a processor introduces latency in a critical timing path, thereby degrading processor performance.
A second source of performance problems within a conventional data processing system is the manner in which caches handle updates. Data processing system caches are typically set associative and accordingly contain a number of congruence classes that each include a number of ways or members. Each of the members can store a cache line of data, for example, 64 bytes. As is well-known to those skilled in the art, the cache line stored within each congruence class member is recorded in an associated directory entry utilizing a tag portion of the cache line address. The directory entry also stores the current coherency state of the associated congruence class member. An update to a congruence class member therefore entails an update of either or both of the tag and coherency state of the corresponding directory entry. Prior art data processing systems handle an update operation by holding off all other processor requests and snoops mapping to a congruence class member until the update to the corresponding directory entry update is complete. The deferral of service for processor requests and snoops causes de facto serialization of cache requests in cases in which multiple requests specifying the same congruence class member are received.
As should thus be apparent, it would be desirable to provide an improved method and system for data processing. In particular, it would be desirable to provide an improved method and system for identifying split bus transactions. In addition, it would be desirable to provide a method and system for performing cache updates that minimize contention for frequently accessed cache lines.
It is therefore one object of the present invention to provide an improved method and system for data processing.
It is another object of the present invention to provide an improved method and system for data communication in a data processing system.
It is yet another object of the present invention to provide an improved method and system for cache management in a data processing system.
The foregoing objects are achieved as is now described. According to a first aspect of the present invention, a data processing system is provided that includes a communication network to which multiple devices are coupled. A first of the multiple devices includes a number of requesters, which are each permanently assigned a respective one of a number of unique tags. In response to a communication request by a requester within the first device, a tag assigned to the requestor is transmitted on the communication network in conjunction with the requested communication transaction. According to a second aspect of the present invention, a data processing system includes a cache having a cache directory. A status indication indicative of the status of at least one of a plurality of data entries in the cache is stored in the cache directory. In response to receipt of a cache operation request, a determination is made whether to update the status indication. In response to the determination that the status indication is to be updated, the status indication is copied into a shadow register and updated. The status indication is then written back into the cache directory at a later time.
The above as well as additional objects, features, and advantages of the present invention will become apparent in the following detailed written description.

Cache having virtual cache controller queues

International Business Machines Corporation


A slapper detonator includes an explosive pellet disposed within a detonator housing and a bridge chip disposed within a pocket defined between a pair of printed circuit boards. One of the printed circuit boards is disposed between the bridge chip and the explosive pellet and includes an opening centered over the bridge element to permit a flyer to accelerate before impacting the explosive pellet. The printed circuit board with the opening also establishes a connection between the bridge contact pads and metalized patterns or pads on the other printed circuit board which are, in turn, connected with metalized patterns or pads on an opposite side of the board. Various input contacts can be attached to the metalized pads, including an adapter board which converts side-by-side pads to concentric pads to permit coaxial connectors to be used. The slapper detonator can be used with a hermetic feed-through assembly having a feed-through housing which connects to a fuze housing in hermetically sealed relation and output contacts which mate in a detachable manner with the input contacts on the slapper detonator to permit removal of the detonator from the fuze electronics for periodic inspection and testing.

1. Field of the Invention
The present invention relates generally to electrical initiation systems for explosive devices and, more particularly, to low impedance slapper detonators and feed-through assemblies for use in initiation systems of explosive devices such as, for example, advanced warheads.
2. Discussion of the Related Art
The explosive charge in a slapper detonator is initiated by a flyer plate which is driven to a very high speed over a short distance by the hot gaseous metal and plasma generated by passing a very high current pulse through an exploding foil initiator (EFI) having a thin foil or film bridge. The term "exploding" is used because of the required speed of transformation of the bridge from solid metal to super heated metal vapor and plasma. If the bridge is heated too slowly, it can melt and perhaps electrically open as does a common electrical fuse. Heating the bridge too slowly can also melt, blister, or otherwise damage the material used as the flyer plate. In order to successfully initiate an EFI, it is important to heat the bridge to its melting point before the flyer plate has been disturbed. If the bridge is heated quickly enough, the power in the high current firing pulse flowing through the plasma from the bridge material (which is typically measured in megawatts) goes directly into accelerating the flyer plate material away from the bridge area at an extremely high rate. In other words, the current through the bridge must be as high as possible by the time the total energy dissipated in the bridge is high enough to cause it to burst.
A very rapid rate-of-rise of the current pulse into the initiator, e.g., on the order of tens of thousands of amperes per microsecond, is desirable in order to achieve suitable acceleration of the flyer plate; however, the rate-of-rise of the current pulse is limited by the inductance of the initiating system. Inductance is the physical property of electrical circuits which acts to directly oppose changes in current flow. The voltage drop across an inductor is simply its inductance times the time rate of change of current (L di/dt). For a hypothetical initial firing voltage of 1,400 volts, a 20 thousand V/.mu.s rise requires an inductance of no more than 70 nanohenries (nH).
The simple formula set forth above can only predict the initial slope of the current pulse. The effective average rise until the bridge bursts is usually somewhat lower. The formula can, however, be used to accurately estimate the actual inductance of an initiator system from the initial slope of a firing current trace. For a typical EFI and firing circuit, a total system inductance of 20 nH or less is a more reasonable design target.
EFI's for slapper detonators have often been formed by etching a foil bridge on flexible printed circuit boards made of polyimide and placing a hollow, cylindrical member or barrel on a side of the printed circuit board opposite the bridge to create a gap across which the polyimide material can accelerate before impacting an initiating explosive on the other side of the barrel. A number of different approaches have been developed to connect such EFI's to fuze electronics and other sources of current. One approach involves laying the EFI across a pair of layered striplines which are longitudinally offset from one another such that one end of the bridge contacts a copper strip on the bottom stripline while the other end of the bridge contacts a copper strip on the top stripline. The striplines are then clamped or soldered to the fuze electronics to complete the connection. Another approach involves folding the flexible printed circuit board such that the bridge is disposed on an inner surface thereof and providing terminal ends of the boards with holes surrounded by concentric contact rings in the form of a bulls eye so that the printed circuit board can be electrically coupled with the fuze electronics using a bolt inserted through the holes. Yet another approach using flexible printed circuit board technology involves use of a contact board having a coaxial connector thereon with inner and outer contacts configured to mate with the fuze electronics and a transition board disposed between the EFI and the contact board to connect opposite ends of the bridge with inner and outer contacts of the coaxial connector via plated through-holes formed in the boards.
A disadvantage of these approaches is that they are difficult to incorporate into a hermetic package without incorporating the EFI and fuze electronics in a single sealed package which would preclude periodic testing of the fuze electronics by preventing disassembly. An approach achieving hermeticity has been developed utilizing a folded flexible printed circuit board with a bulls eye connector disposed between a barrel and a glass-to-metal sealed feed-through. The feed-through includes pins embedded within glass and contacting portions of the EFI; however, in order to match thermal coefficients of the glass and the metal contacts, it is necessary to use exotic metals such as Kovar which are not highly conductive and, therefore, can increase the inductance of the system. A disadvantage of detonators utilizing flexible printed circuit boards in general is that the thicknesses of the polyimide material and copper cladding are fixed thereby limiting the bridge and flyer plate design to commercially available thicknesses which may not be optimal.
Exploding foil initiators have also been formed using silicon chip technology by depositing a layer of metal on a silicon or ceramic substrate to define a bridge and covering the bridge with an oxide layer which functions as a flyer plate. These so-called bridge chips are advantageous in that the thickness of the bridge and flyer plate materials can be tailored for the particular application; however, connecting firing electronics to such chips can be difficult. One approach involves mounting the chip on a carrier with plural J-shaped leads configured to mate with the firing electronics and connecting the bridge contact pads with the leads using fine wires. While this approach is widely used in commercial applications, there are certain disadvantages when using this technique to build a slapper detonator.
Firstly, the use of fine wires tends to increase the inductance and resistance of the initiating system thereby increasing overall energy requirements. Inductance can be lowered to suitable levels by using a large number of wires, however, connecting a large number of fine wires in this manner is a delicate procedure requiring complex and costly equipment. The presence of a large number of wires also makes it difficult to position a barrel immediately adjacent the bridge. Another approach involves drilling holes through the chip, plating the holes and using the plated through-holes to connect to a stripline or printed circuit board of the firing electronics. While this approach reduces inductance and permits placement of a barrel directly over the bridge, it is difficult and costly to form through-holes in a silicon or ceramic substrate. Still another approach involves separating the copper strip from a stripline of the firing electronics and bending the copper strips so that they overlap the contact pads on the chip. Some of the disadvantages of this type of approach are that it is difficult to assemble and can result in higher inductance due to bending of the copper strip. An additional disadvantage of the aforementioned exploding foil initiators with bridge chips is that the exploding foil initiators are soldered to the firing electronics and thus are not easily removable therefrom to permit periodic testing of the firing electronics.

Low impedence slapper detonator and feed-through assembly


A flow meter for determining the flow rate of a fluid through a conduit, including an upper body having an inlet chamber, an acoustic channel, an outlet chamber, a sound wave generator, and a sound wave receiver. The inlet chamber, acoustic channel, and outlet chamber are fluidly connected together and are oriented so as to create a symmetrical fluid pathway through the inlet chamber, the acoustic channel the outlet chamber. The sound wave generator and the sound wave receiver are aligned along a longitudinal axis of the acoustic channel and the sound wave generator is creates a sound wave that moves along the longitudinal axis of the acoustic channel as fluid flows through the acoustic chamber. The receiver detects that sound wave that has moved through the acoustic channel and such information is used to determine the flow rate of the fluid through the flow meter.

The measurement of liquid flow through a pipe is commonly used in many domestic and industrial applications. The flow rate of a liquid through a pipe is typically measured by use of a flow meter. These flow meters include a body that is connected in-line with the flow of liquid in the pipe. A rotation turbine is connected to the body and the rate of rotation of the turbine caused by the flow of the liquid through the flow meter is used to determine the flow rate of a liquid through the pipe. Examples of these turbine-type flow meters are illustrated in US 2003/0024324 and the references cited therein. Although these turbine-type flow meters are commonly used, these flow meters contain moving parts that wear out over time, thereby adversely affecting proper flow rate measurements and/or result in complete failure of the flow rate meter. In view of the current state of flow rate meters, there is a need for a flow rate meter that has fewer or no moving parts and optionally can be easily substituted in the housing or body of existing flow rate meters.

Hydraulic system for ultrasonic flow measurement using direct acoustic path approach


A mobile terminal is disclosed herein. The mobile terminal may include a body, a display, a transceiver for short range radio communication, and a controller configured to control data transfer through the transceiver. The controller may be configured to determine whether a request for data is received, determine whether an input is required to allow authorize the data transfer, and determine whether the data transfer is authorized, and transfer data through the transceiver when the data transfer is authorized. The input may be received without displaying a prompt on the display for the input. The input may be received while the display is turned off. Moreover, the input may be a prescribed movement of the body of the mobile terminal or an application of a prescribed amount of force on the mobile terminal.

1. Field
The present disclosure relates to a mobile terminal, and particularly, to a mobile terminal capable of performing short-range radio communication, and a method for controlling the same.
2. Background
Mobile terminals capable of performing short-range radio communication and methods for controlling the same are known. However, they suffer from various disadvantages.

Mobile terminal and control method for the same


A method of manufacturing an optical element includes testing the optical element by using an interferometer optics generating a beam of measuring light illuminating only a sub-aperture of the tested optical element. The interferometer optics comprises a hologram. Results of the sub-aperture measurement are stitched together to obtain a measuring result with respect to the full surface of the optical element. Further, a method of calibrating the interferometer optics includes performing an interferometric measurement using a calibrating optics having a hologram covering only a sub-aperture of the full cross section of the beam of measuring light generated by the interferometer optics and stitching together the sub-aperture measurements to obtain a result indicative for the full cross section of the interferometer optics.

1. Field of the Invention
The present invention relates to a method of manufacturing an optical element. In particular, the invention relates to a method of manufacturing an optical element having an aspherical optical surface having a rotational symmetry.
2. Brief Description of Related Art
The optical element having the optical surface is, for example, an optical component such as an optical lens or an optical mirror used in optical systems, such as telescopes used in astronomy, and systems used for imaging structures, such as structures formed on a mask or reticle, onto a radiation sensitive substrate, such as a resist, in a lithographic method. The success of such an optical system is substantially determined by the accuracy with which the optical surface can be machined or manufactured to have a target shape determined by a designer of the optical system. In such manufacture it is necessary to compare the shape of the machined optical surface with its target shape, and to determine differences between the machined and target surfaces. The optical surface may then be further machined at those portions where differences between the machined and target surfaces exceed e.g. predefined thresholds.
Interferometric apparatuses are commonly used for high precision measurements of optical surfaces. Examples of such apparatus are disclosed in U.S. Pat. No. 4,732,483, U.S. Pat. No. 4,340,306, U.S. Pat. No. 5,473,434, U.S. Pat. No. 5,777,741, U.S. Pat. No. 5,488,477. The entire contents of these documents are incorporated herein by reference.
The conventional interferometer apparatus for measuring a spherical optical surface typically includes a source of sufficiently coherent light and an interferometer optics for generating a beam of measuring light incident on the surface to be tested, such that wave fronts of the measuring light have, at a position of the surface to be tested, a same shape as the target shape of the surface under test. In such a situation, the beam of measuring light is orthogonally incident on the surface under test, and is reflected therefrom to travel back towards the interferometer optics. Thereafter, the light of the measuring beam reflected from the surface under test is superimposed with light reflected from a reference surface and deviations of the shape of the surface under test and its target shape are determined from a resulting interference pattern.
While spherical wave fronts for testing spherical optical surfaces may be generated with a relatively high precision by conventional interferometer optics, more advanced optics, which are also referred to as compensators, null lens arrangements, or K-systems, are necessary to generate beams of measuring light having aspherical wave fronts such that the light is orthogonally incident at each location of the aspherical surface under test. Background information relating to null lens arrangements or compensators is available e.g. from the text book of Daniel Malacara "Optical Shop Testing", 2nd Edition, John Wiley & Sons, Inc. 1992, Chapter 12.
For many types of aspherical optical surfaces to be tested it is necessary to provide a null lens system or a compensator having one or more lenses with a diameter which corresponds to a diameter of the aspherical surface under test. In particular, for aspherical surfaces having a convex shape, the diameters of lenses of the compensator may have to be greater than the diameter of the aspherical lens.
Manufacture of null lens systems having lenses with a great diameter and having a high accuracy is a considerable problem and not only incurs high costs. From the article by M. Bray, "Stitching interferometer for large optics: Recent Developments of a System for Laser Megajoule Components", Lawrence Livermore Nat. Lab., CEA. in Proc. SPIE—Int. Soc. Opt. Eng. (USA), USA: SPIE—Int. Soc. Opt. Eng., vol. 3492, pt. 1-2[+suppl.], 1999, pages 946-956, there is known a method of testing a large mirror having a spherical shape by performing interferometric tests at a plurality of overlapping portions or sub-apertures of the optical surface to be tested. Each portion has a lower diameter than the surface to be tested. Measured surface data of each portion are then stitched together to generate surface data representing a map of the surface shape of the tested mirror. The data processing for stitching the various data portions includes determining magnitudes of a piston term, a tilt, and a lateral translation between adjacent overlapping portions. This is possible since the mirror has a spherical shape such that each measured portion of the whole surface represents a small portion of the overall sphere and all portions may be stitched together to represent the overall sphere by determining only the respective parameters mentioned above, i.e. piston, tilt and lateral translation.
While the method of stitching interferometry is useful in measuring large spherical optical surfaces by using an interferometer optics of a lower diameter, applications of stitching interferometry to testing of large aspherical surfaces by using null lens systems or compensators having a low diameter did not provide satisfactory results in the past.

Method of manufacturing an optical element


A separable plastic male-to-male connector includes a pair of connector units each having a planar base and a plurality of protrusions extending outward from the base and being oriented on the base so as to form a matrix. The matrix has a plurality of lateral and longitudinal rows wherein a distance C.sub.L1 is between centers of laterally adjacent male protrusions, and wherein a distance C.sub.L2 is between centers of longitudinally adjacent male protrusions. Each protrusion includes a head portion and a stem portion. The head portion has a height K.sub.H equal to 0.50*(C.sub.L1 +C.sub.L2)/2 and a diameter K.sub.D equal to 0.75*(C.sub.L1 +C.sub.L2)/2. The stem portion has a first end attached to the base and a second opposed end attached to the head portion. The stem portion has a height S.sub.H equal to 0.63*(C.sub.L1 +C.sub.L2)/2 and a diameter S.sub.D equal to 0.56*(C.sub.L1 +C.sub.L2)/2. C.sub.L1, C.sub.L2, K.sub.H, K.sub.D, S.sub.H, and S.sub.D each have a tolerance of .+-.6%. The total combined tolerance for C.sub.L1, C.sub.L2, K.sub.H, K.sub.D, S.sub.H, and S.sub.D taken together is no more than .+-.6%.

The present invention relates to a connector apparatus, and more particularly, to a male-to-male connector apparatus having a symmetrical and uniform connector matrix which has broad application in a variety of fields, arts and technologies.
There are generally two types of modular interlocking connector apparatuses: male-to-female connector matrices and male-to-male connector matrices. The former are disadvantages for numerous reasons including the need to properly orient and align the male and female parts, the added costs of having different manufacturing equipment and technique for the male and female parts, and the aesthetic differences. Male-to-male connectors alleviate the problems of the male-to-female connectors.
Male-to-male connectors are well known in many arts and have been for a long time. Male-to-male connectors typically employ a first male connector matrix removably attachable to a second male connector matrix. The first and second male connector matrices are typically identical. Each matrix typically includes a plurality of male protrusions extending from a base member. Furthermore each male protrusion typically includes a stem attached to the base member and a wider head section attached to the stem opposite the base member. The matrix arrangement of the male protrusions is designed so that the head section of each protrusion on the first male connector is removably engageable with the male protrusions of the second connector matrix and vice versa. The shape and placement of the male connectors on the base surface must be done to exacting specifications in order to achieve proper alignment and engagement. Accordingly, there are many possible dimensions and shapes which the male protrusions may have as evidenced by, for example, U.S. Pat. Nos. 5,212,853; 5,201,101; 5,097,570; 4,147,007; 4,290,174; 3,955,245; 3,266,113; and 3,101,517. There is a continuing desire to create a male-to-male connector matrix which provides more secure engagement, easier disengagement, less shear or movement in the lateral direction when engaged, and broader application due to its look and feel.

Male-to-male connector apparatus having symmetrical and uniform connector matrix


A vascular prosthesis comprises pericardial, fascial, or other tissue formed over a tubular support frame. A first exemplary tubular support frame comprises an inner helical member and an outer helical member, where the tissue is rolled and captured therebetween. A second exemplary tubular support frame comprises a plurality of ring elements which are located alternately on the outside and on the inside of the rolled tissue. Other exemplary frames employ fasteners for penetrating the rolled tissue and attaching tissue to frame elements. The tissue is preferably obtained from the patient who is to receive the vascular prosthesis, with the tissue being mounted over the frame immediately prior to use.

1. Field of the Invention
The present invention relates generally to medical methods and devices, and more particularly to a method and apparatus for forming vascular prostheses from host tissue sources.
Coronary and peripheral atherosclerosis are characterized by partial or total occlusion of the arteries resulting from the accumulation of lipids, smooth muscle cells, connective tissue, and glycosaminoglycans on the arterial wall. Atherosclerosis of the coronary arteries is a particular problem and can cause angina and myocardial infarction (heart attack). Although many coronary lesions can be treated with percutaneous techniques, such as angioplasty and atherectomy, more tortuous and severely diseased arteries frequently require surgical intervention and bypass, commonly referred to as coronary artery bypass graft (CABG) surgery.
CABG surgery relies on the surgical attachment of a vascular graft to bypass the arterial occlusion in order to restore blood flow to the coronary vasculature. The nature of the vascular graft can have a significant impact on the ultimate success of the procedure. A preferred vascular graft is formed from autologous internal mammary artery (IMA), where the resulting grafts have a patency rate approaching 95% ten years following the procedure. The use of IMA grafts, however, is limited by their length, and the need to harvest the artery from the patient can result in post-surgical complications. The autologous saphenous vein is a second common source for vascular grafts. While generally available in the necessary lengths, the saphenous vein is not ideally suited for replacement as an arterial vessel, and patency rates at ten years are often below 50%. Moreover, removal of the saphenous vein from the leg can also cause post-surgical complications.
Because of the limitations on autologous vascular sources, a variety of synthetic and non-autologous biological prostheses have been proposed. Common synthetic prostheses are formed from Dacron.RTM. and PTFE, and can perform well when employed in larger diameters, i.e., above 6 mm. Smaller synthetic prostheses, however, occlude at a relatively high rate. Non-autologous biological conduits which have been utilized as vascular prostheses include human umbilical vein grafts and bovine internal mammary arteries. Synthetic grafts have also been seeded with human and other mammalian cells or proteins, e.g., collagens, in an effort to improve their long-term patency rate. Presently, however, none of these approaches has demonstrated long-term patency, particularly in smaller diameter grafts.
Of particular interest to the present invention, preparation of vascular prostheses from autologous pericardium has been proposed. Pericardial tissue is harvested from the patient and formed into a tubular graft by suturing along a longitudinal line. While promising, the use of sutures can result in an irregular seam which, in turn, can cause turbulent blood flow and result in clot formation. Moreover, such grafts are unsupported and subject to kinking and collapse. The grafts further lack an inherently round geometry and are subject to dimensional changes, e.g., elongation and aneurysmal formation. Because of the dimensional uncertainty, it is difficult to match such grafts to the precise dimensional requirements of the particular application, e.g, caliber and length. The suturing of vascular prostheses from pericardium is labor intensive and time consuming, and the resulting structures are subject to rupture and other structural failure. Thus, the outcome of using sutured pericardial tissue grafts is uncertain at best.
For these reasons, it would be desirable to provide improved vascular prostheses for use in CABG and other procedures. Such prostheses should be biocompatible with the patient, resistant to kinking and collapse, and easy to implant. Moreover, the prostheses should be non-thrombogenic, resistant to infection, and easy to sterilize and store. It would be particularly desirable to provide improved methods and apparatus for preparing vascular prostheses from autologous tissue sources, where the prostheses can be prepared in a range of diameters and lengths, and can be readily assembled in the operating room after the tissue has been harvested. In particular, the vascular prostheses should be readily assemblable, preferably without suturing, in a manner that allows precise and uniform dimensions and preferably be available in a kit form to facilitate assembly.
2. Description of the Back ground Art
U.S. Pat. No. 4,502,159, describes a vascular prosthesis made by suturing glutaraldehyde-treated pericardial tissue along a longitudinal seam. SU 1217362 (Abstract) describes reinforcing arteries by securing pericardial tissue over the artery. U.S. Pat. No. 3,562,820, describes forming tissue-containing prostheses over removable mandrels. The use of glutaraldehyde and other agents for treating tissue and prosthetic devices to reduce antigenicity is described in U.S. Pat. Nos. 3,988,782; 4,801,299; 5,215,541, and Brazilian applications 89/03621 and 90/03762. U.S. Pat. No. 4,539,716, describes the fabrication of an artificial blood vessel from collagen and other natural materials. U.S. Pat. Nos. 3,894,530 and 3,974,526, describe the formation of vascular prostheses from the arteries or veins present in the umbilical cord. U.S. Pat. No. 5,372,821, describes the use of tissue for forming artificial ligament grafts for use in orthopedic procedures. U.S. Pat. No. 3,408,659, describes the preparation of vascular artificial prostheses from other body lumens. French application FR 2,714,816, (Abstract) discloses a helically supported vascular prosthesis. A number of medical literature publications describe the use of vascular prostheses formed form tissue. See, for example, Rendina et al. (1995) J. Thorac. Cardiovasc. Surg. 110:867-868; Hvass et al. (1987) La Presse Medicale 16:441-443; Allen and Cole (1977) J. Ped. Surg. 12:287-294; and Sako (1951) Surgery 30:148-160. Other patents and published applications relating to synthetic vascular grafts include U.S. Pat. Nos. 4,728,328; 4,731,073; 4,798,606; 4,820,298; 4,822,361; and 4,842,575; and PCT publications WO 94/22505 and WO 95/25547. Patents and published applications relating to kits for preparing replacement heart valves from pericardial and other autologous tissue sources are described in U.S. Pat. Nos. 5,163,955; 5,297,564; 5,326,370; 5,326,371; 5,423,887; and 5,425,741.

Method and apparatus for forming vascular prostheses


Embodiments of an image sensor are provided. The image sensor includes a sensing layer, a filter unit and a microlens. The filter unit is disposed on the sensing layer, and the microlens is disposed on the filter unit. The filter unit has a gradient refractive index. Therefore, the sensitivity of the image sensor is improved.

1. Field of the Invention
The present disclosure relates to an image sensor, and in particular to an image sensor having a filter unit.
2. Description of the Related Art
In general, a digital camera utilizes an image sensor to sense light and generate an image signal, and thus a picture taken by the digital camera can be generated according to the image signal.
With the development of digital cameras, a high quality of image signals is requested. The quality of image signals is important, especially when the digital camera is used in a low-luminance environment.
Although image sensors have been generally adequate for their intended purposes, they have not been entirely satisfactory in all respects. Consequently, it would be desirable to provide a solution for improving image sensors.

Image sensor and manufacturing method thereof


A charge pump circuit and a method of compensating current mismatch in a charge pump circuit. The charge pump circuit comprises a core charge pump circuit; a replica charge pump circuit for sensing a current mismatch in the core charge pump circuit and for converting the sensed current mismatch into a voltage signal V_ctrl; wherein V-ctrl is utilized for compensating the current mismatch in the core charge pump circuit.

A charge pump is an electronic circuit that uses switches to control the connections of voltages to double voltages, invert voltages, or generate arbitrary voltages, depending on the controller and circuit topology. An example for a charge pump circuit application is in phase locked loop circuits (PLL). For designing a charge pump circuit, an important objective is to minimize the mismatch between "up" (pull-up) and "down" (pull-down) currents. In an integer-N synthesizer, the current mismatch will cause the charge pump's output spectrum to have a higher reference spur. For fractional-N synthesizer, the current mismatch will cause an extra problem, known as higher in-band phase noise.
FIG. 1 shows an existing charge pump circuit that attempts to deal with the mismatch problem between currents "up" and "down". In this circuit, the original current source I_bias is mirrored to a common current branch for presenting "up" (I_up) and "down" (I_down) currents to N-MOS transistor M1 and P-MOS transistor M2 respectively. Between these two current carrying transistors (M1, M2), there are four trans-gate switches (S1, S2, S3 and S4) of the same size and they form the current branch 101 (S1 and S2) parallel to a dummy branch 100 (S3 and S4). Each branch has its two trans-gate switches serially connected. The charge pump output voltage V_ds is taken at the CP_out point between S1 and S2 and a reference voltage V_ref is taken between S3 and S4. Linking charge pump output (V_ds) and the voltage reference V_ref, a negative feedback is formed via an Operational Amplifier (Op) so that the voltage value V_ref follows V_ds. In these branches, D and U are digital signals from a phase frequency detector (PFD) to control the trans-gate switches (S1 to S4) so that the pumping of the positive and negative current (CP_out) is regulated. In this circuit, a charge injection is minimized by implementing the identical switches (S1 to S4) with a minimal size and the possible overlap charge injection is reduced by fine-tuning the size of current carrying transistors (M1, M2). During operation, M1 and M2 are not switched on or off to prevent current switching effects on the drain of the current sources. When the charge pump is off i.e. both S1 and S2 are closed, the current is diverted into a dummy current branch 100 via S3 and S4.
In the charge pump circuit, there exists a systematic current variation due transistor mismatch between M1 and M2. Consequently, the resulting current mismatch of the charge pump circuit is in practice difficult to avoid.
Referring to FIG. 2, the simulation result for the charge pump circuit of FIG. 1 is shown. The vertical axis represents the electric current value and the horizontal axis gives the reference voltage V_ref (0˜1.8V) value, which follows the charge pump output voltage V_ds. The current passing through M1 (100 μA) is marked with I_up (curve 200) and the current passing through M2 (−95 μA) is marked with I_down (curve 202). The current mismatch is illustrated by the current_mismatch curve 204. It can be observed that the circuit is not able to compensate the current mismatch and resulted current mismatch is quite large.
Another existing charge pump circuit is illustrated in FIG. 3. The charge pump connects an original current source (I_bias) with a feedback network portion 300, a core charge pump portion 302 and a replica bias portion 304. This circuit uses the replica bias circuit 304 to equalize up and down currents regardless of the charge pump's output voltage V_ds. However, the voltage range V_ds of this charge pump is narrow which inhibits the feedback loop from operating properly. Such charge pump circuits cannot have good current match and are limited in terms of dynamic voltage range.
There are some charge pump circuits using digital circuits to control current mismatch. However, the digital circuit has to be turned on at all times to achieve good current match, which causes problems to the charge pump circuit.
A need therefore exists for compensating current mismatch in a charge pump circuit that seeks to address at least one of the above problems.

Agency for Science, Technology and Research


A paving package has a spaced plurality of paving elements interconnected through a flexible connecting medium. The paving elements are wound into a roll. An outdoor surface destined to receive the paving elements is prepared by laying bedding material on the surface. The roll is brought near the surface and unwound to lay at least some of the paving elements in a predetermined region on the surface.

1. Field of the Invention
The present invention relates to apparatus and methods for paving, and in particular, to paving by laying down a plurality of discrete elements.
2. Description of Related Art
Paving outdoor surfaces requires relatively heavy materials that can withstand the elements outdoors. Consequently, conventional outdoor paving techniques require one to transport and lay many hundreds, if not thousands, of pounds of paving material, which becomes a serious logistical challenge.
Stones, bricks, and other masonry articles have been used to pave walkways, streets, patios, etc. Cobblestones are an early example. A more recent example is the use of paving bricks or pavers. As shown in FIG. 8, an earthen surface can be prepared by placing a layer of gravel 10 in a shallow excavation. Gravel layer 10 will be compacted in the usual fashion. The region to be paved is encompassed by border elements, in this case wooden beam 12, although in some cases the edge restraint may be a vertical plastic strip with a lower ledge (not shown) designed to slip under the paving bricks. Gravel layer 10 is covered with a layer of sand 14. Solid paving bricks P are laid atop sand layer 14 in a pleasing pattern, with some arranged transverse to the others. A gap is left between paving bricks P, which is filled with sand S that permits water drainage through layers 14 and 10 to the earth E below.
Laying paving bricks P is time-consuming since one must be careful to maintain a uniform gap between bricks, lay the bricks in a pattern that is pleasing, and in some cases choose a sequence of differently colored bricks to produce a pleasant appearance.
Known composite materials are used as a replacement for wood. These composites may include a plastic material with cellulosic filler such as wood flour, wood chips, comminuted coconut or peanut shells, etc. The plastic may be a thermoplastic such as polyethylene, polyvinyl chloride, polypropylene, ABS, or a mixture thereof. Such composite materials are commercially available as deck materials from Trex Company, Inc of Winchester, Va.; and as Timbertech™ products from Crane Plastics Company, L.P, of Columbus, Ohio. These types of composites are described in U.S. Pat. Nos. 2,041,217; 5,474,722; 5,851,469; 5,866,264; and 6,272,808, as well as US Patent Application Publication No. 2002/0066248.
The strength and durability of natural or synthetic rubber can be improved by a vulcanizing process. In some cases sulfur is dispersed or dissolved in the rubber and then heated to create cross-links between long-chain molecules in the rubber. The process can be made more efficient by using chemical accelerators to hasten the cross-linking.
See also U.S. Pat. Nos. 1,592,591; 3,568,579; 4,681,482; 4,963,054; 5,588,775; 6,267,531; 6,551,016; U.S. Reissue Pat. RE35,380; and US Patent Application Publication Nos. 2008/0276562; 2009/0136296; 2011/0239572; and 2013/0086869.

Packages and methods for packaging and for laying paving elements


An external capability for measuring roundtrip latency in a conferencing system is provided. The external capability for measuring roundtrip latency in a communication system may include functions of generating a content event, detecting the content event in a received content stream including the content event, determine a first time associated with generation of the content event and a second time associated with detection of the content event, and computing a roundtrip latency based on a difference between the second time and the first time. The content event may be a visual event or an aural event. These functions may be implemented using one or more modules or elements. A computing device may be used to generate and detect the content event and to compute the roundtrip latency. Various other arrangements of modules or elements may be used to provide the functions.

Many video conferencing systems are prevalent for use in meetings for enterprises. Such video conferencing systems are typically room-to-room or station-to-station video conferencing systems. Additionally, the use of video calls (e.g., via tablet computers, smartphones, and like devices) continues to increase. In many communication systems, latency within the communication system may result in an unpleasant experience for users of services in the communication system. For example, latency in a conferencing service that is supported by a communication system may result, at best, in an experience that may be unpleasant for the users of the conferencing service and, in the worst case, in a conferencing service that may be unusable by the users.

External roundtrip latency measurement for a communication system


A logging-while-drilling density sensor includes a gamma ray source and at least two NaI detectors spaced apart from the source for determining measurements indicative of the formation density. An acoustic caliper is used for making standoff measurements of the NaI detectors. Measurements made by the detectors are partitioned into standoff bins. An adaptive spine and rib method uses the standoff measurements to obtain density estimates. The method of the invention may also be used with neutron porosity logging devices.

1. Field of the Invention
This invention relates generally to borehole logging apparatus and methods for performing nuclear radiation based measurements. More particularly, this invention relates to a new and improved apparatus for effecting formation density logging in real time using gamma rays in a measurement-while-drilling (MWD) tool.
2. Background of the Art
Oil well logging has been known for many years and provides an oil and gas well driller with information about the particular earth formation being drilled. In conventional oil well logging, after a well has been drilled, a probe known as a sonde is lowered into the borehole and used to determine some characteristic of the formations which the well has traversed. The probe is typically a hermetically sealed steel cylinder which hangs at the end of a long cable which gives mechanical support to the sonde and provides power to the instrumentation inside the sonde. The cable also provides communication channels for sending information up to the surface. It thus becomes possible to measure some parameter of the earth's formations as a function of depth, that is, while the sonde is being pulled uphole. Such "wireline" measurements are normally done in real time (however, these measurements are taken long after the actual drilling has taken place).
A wireline sonde usually transmits energy into the formation as well as a suitable receiver for detecting the same energy returning from the formation. These could include resistivity, acoustic, or nuclear measurements. The present invention is discussed with reference to a density measurement tool that emits nuclear energy, and more particularly gamma rays, but the method of the present invention is applicable to other types of logging instruments as well. Wireline gamma ray density probes are well known and comprise devices incorporating a gamma ray source and a gamma ray detector, shielded from each other to prevent counting of radiation emitted directly from the source. During operation of the probe, gamma rays (or photons) emitted from the source enter the formation to be studied, and interact with the atomic electrons of the material of the formation by photoelectric absorption, by Compton scattering, or by pair production. In photoelectric absorption and pair production phenomena, the particular photons involved in the interacting are removed from the gamma ray beam.
In the Compton scattering process, the involved photon loses some of its energy while changing its original direction of travel, the loss being a function of the scattering angle. Some of the photons emitted from the source into the sample are accordingly scattered toward the detector. Many of these never reach the detector, since their direction is changed by a second Compton scattering, or they are absorbed by the photoelectric absorption process of the pair production process. The scattered photons that reach the detector and interact with it are counted by the electronic equipment associated with the detector.
Examples of prior art wireline density devices are disclosed in U.S. Pat. Nos. 3,202,822; 3,321,625; 3,846,631; 3,858,037, 3,864,569 and 4,628,202. Wireline formation evaluation tools such as the aforementioned gamma ray density tools have many drawbacks and disadvantages including loss of drilling time, the expense and delay involved in tripping the drillstring so as to enable the wireline to be lowered into the borehole and both the build up of a substantial mud cake and invasion of the formation by the drilling fluids during the time period between drilling and taking measurements. An improvement over these prior art techniques is the art of measurement-while-drilling (MWD) in which many of the characteristics of the formation are determined substantially contemporaneously with the drilling of the borehole.
Measurement-while-drilling logging either partly or totally eliminates the necessity of interrupting the drilling operation to remove the drillstring from the hole in order to make the necessary measurements by wireline techniques. In addition to the ability to log the characteristics of the formation through which the drill bit is passing, this information on a real time basis provides substantial safety advantages for the drilling operation.
One potential problem with MWD logging tools is that the measurements are typically made while the tool is rotating. Since the measurements are made shortly after the drillbit has drilled the borehole, washouts are less of a problem than in wireline logging. Nevertheless, there can be some variations in the spacing between the logging tool and the borehole wall ("standoff") with azimuth. Nuclear measurements are particularly degraded by large standoffs due to the scattering produced by borehole fluids between the tool and the formation.
U.S. Pat. No. 5,397,893 to Minette, the contents of which are fully incorporated herein be reference, teaches a method for analyzing data from a measurement-while-drilling (MWD) formation evaluation logging tool which compensates for rotation of the logging tool (along with the rest of the drillstring) during measurement periods. The density measurement is combined with the measurement from a borehole caliper, preferably an acoustic caliper. The acoustic caliper continuously measures the standoff as the tool is rotating around the borehole. If the caliper is aligned with the density source and detectors, this gives a determination of the standoff in front of the detectors at any given time. This information is used to separate the density data into a number of bins based on the amount of standoff. After a pre-set time interval, the density measurement can then be made. The first step in this process is for short space (SS) and long space (LS) densities to be calculated from the data in each bin. Then, these density measurements are combined in a manner that minimizes the total error in the density calculation. This correction is applied using the "spine and rib" algorithm and graphs such as that shown in FIG. 1. In the figure, the abscissa 1 is the difference between the LS and SS densities while the ordinate 3 is the correction that is applied to the LS density to give a corrected density using the curve 5.
U.S. Pat. No. 5,513,528 to Holenka et al teaches a method and apparatus for measuring formation characteristics as a function of azimuth about the borehole. The measurement apparatus includes a logging while drilling tool which turns in the borehole while drilling. The down vector of the tool is derived first by determining an angle φ between a vector to the earth's north magnetic pole, as referenced to the cross sectional plane of a measuring while drilling (MWD) tool and a gravity down vector as referenced in said plane. The logging while drilling (LWD) tool includes magnetometers and accelerometers placed orthogonally in a cross-sectional plane. Using the magnetometers and/or accelerometer measurements, the toolface angle can usually be determined. The angle φ is transmitted to the logging while drilling tool thereby allowing a continuous determination of the gravity down position in the logging while drilling tool. Quadrants, that is, angular distance segments, are measured from the down vector. Referring to FIG. 2, an assumption is made that the down vector defines a situation in which the standoff is at a minimum, allowing for a good spine and rib correction. A drawback of the Holenka method is that the assumption of minimum standoff is not necessarily satisfied, so that the down position may in fact correspond to a significant standoff: without a standoff correction and the results may be erroneous.
In a centralized or stabilized tool, the standoff will generally be uniform with azimuth. Holenka (U.S. Pat. No. 5,513,528) and Edwards (U.S. Pat. No. 6,307,199) also show how azimuthal measurements of density may be diagnostic of bed boundaries intersected by an inclined borehole. In the absence of standoff corrections, this can only be a qualitative measurement and the absolute density measurements may be suspect.
U.S. patent application Ser. No. 10/004,650 of Kurkoski, now U.S. Pat. No. 6,584,837 having the same assignee and the contents of which are incorporated herein by reference, teaches the use of a dual detector density logging tool with a standoff measuring device end a magnetometer for obtaining an azimuthal density image of a borehole. The standoff measurements are used for correcting the density measurements using the well known spine and rib correction method.
The spine and rib correction method used in Kurkoski and in other prior art methods as illustrated in FIG. 1 determines by empirical methods a correction to the density measurement made by the long spaced detector (LS) using the difference between the LS and the short spaced detector SS measurements. Implicit in such prior art methods is the assumption that the spine and rib is uniquely determined by a single correction. The spine and rib is usually determined under laboratory conditions with the tool immersed in water. In reality, there is more than one spine and rib relation and the actual correction to be applied depends upon numerous factors including the standoff and the composition of the mud. As would be known to those versed in the art, drilling mud includes minerals such as Barite that have a significant gamma ray scattering. As a result of this, it is commonly found that even after applying a single spine and rib correction, there is a significant variation in corrected density measurements with standoff.
Accordingly, there is a need for a method of processing dual detector density logging data that properly corrects for the standoff variations encountered in an MWD logging tool. The present invention satisfies this need.

This patent is subject to a terminal disclaimer.

Method of processing data from a dual detector LWD density logging instrument coupled with an acoustic standoff measurement


A packet processor of a network device determines an amount of free buffer space in a buffer memory currently available for buffering packets, and dynamically determines a value of a threshold for triggering a particular traffic management operation with respect to a packet, to dynamically adjust the value of the threshold based at least in part on a changing amount of free buffer space available for buffering packets in the buffer memory. The packet processor determines, based on a comparison between i) a current fill level of a particular transmit queue in which the packet is to be enqueued and ii) the dynamically adjusted value of the threshold, whether the particular traffic management operation is to be triggered with respect to the packet. When the particular traffic management operation is to be triggered, the packet processor performs the particular traffic management operation with respect to the packet.

Network devices, such as bridges and routers, forward packets through a network based on addresses in the packets. A network device typically includes a plurality of ports coupled to different network links. The network device may receive a packet via one port and process address information in a header of the packet to decide via which other port or ports the network switch should transmit the packet. The network device then enqueues the packet, or a packet descriptor associated with the packet, in one or more transmit queues corresponding to the one or more ports, for subsequent transmission of the packets via the one or more determined ports. When the packet is scheduled for transmission via a port, the network device dequeues the packet, or the packet descriptor associated with the packet, from the corresponding transmit queue and forwards the packet to the port for transmission of the packet via the port.
Network devices often implement various traffic management and congestion avoidance techniques to control flow of traffic to a network device when congestion occurs due, for example, to lack of sufficient resources in the network device, such as buffer space available for queueing packets awaiting transmission from the network device. Such traffic management mechanisms are conventionally triggered in a network device when use of a resource in the network device exceeds a statically defined, predetermined, threshold.

Congestion avoidance in a network device


A Ga2O3-based semiconductor device includes a Ga2O3-based crystal layer including a donor, and an N-doped region formed in at least a part of the Ga2O3-based crystal layer.

A technique of epitaxially growing an undoped (not containing intentionally doped dopant) Ga2O3-based crystal film on a Ga2O3-based substrate is conventionally known (e.g., Patent Literature 1).
A semiconductor device, which has an underlying substrate formed of a Ga2O3-based crystal, a buffer layer epitaxially grown on the underlying substrate and formed of an undoped Ga2O3-based crystal, and a Ga2O3-based crystal layer formed on the buffer layer and containing Si doped as a dopant, is also conventionally known (see, e.g., Non-Patent Literature 1).

National Institute of Information and Communications Technology


A declarative program definition. The definition is analyzed to produce an application contract that describes semantics for sending and receiving application messages during the successful execution of operations by the program. In addition, this analysis may also generate local behaviors associated with the local execution of the program. Alternatively or in addition, the analysis may infer secondary contracts regarding the sending and receiving of application messages, even though the full details of the secondary contracts are not present in the declarative program definition. For instance, the secondary contracts might include error contracts or consistency contracts.

In message-based communication, some applications act as "clients", and some act as a "service". One type of software application is often termed a "service". In a typical client-service model, the client is an application that initiates communication with services (often over a network). A service is an application that waits for clients to communicate with them, and responds to messages received from clients. A single application can serve as both a client and a service. Often, services are incorporated in a "runtime", which provides underlying functionality that can be used by multiple applications that run on that computing system.
In a client-service system, messages are sent between endpoints. Endpoints are places where messages are sent or received (or both), and they define all the information required for the message exchange. A service exposes one or more endpoints, and the client generates an endpoint that is compatible with one of the service's endpoints. An endpoint describes in a standard-based way where messages should be sent, how they should be sent, and what the messages should look like. Multiple clients may communicate with a single endpoint.
Each service has a message exchange contract that describes a particular message exchange in terms of the ordering of messages, the dependencies of messages, whether the message is in-bound or out-bound, the structure of the message, and so forth.
Services can actually be quite complex, and can be constructed declaratively without using imperative code. For example, Web Services Description Language (WSDL) is an eXternsible Markup Language for describing network services as a set of endpoints operating upon document-oriented or procedure-oriented information. The operations and messages are described abstractly, and then bound to a concrete network protocol and message format to define an endpoint. Related concrete endpoints are combined into abstract endpoints (services).

Inference of contract using declarative program definition


A fixated catheter including a tube and a fixating portion. The fixating portion includes a fixating strip having a plurality of outwardly protruding barbs. The fixating strip is spirally wound about a portion of the tube. The fixated catheter can be inserted into the body to place the fixated portion adjacent to body tissue so that the barbs engage the body tissue to minimize migration of the fixated catheter during chronic use.

The present invention relates to catheters, and more particularly to fixated catheters suitable for chronic sampling and delivery of fluids.
Catheters can be used to access specific portions of animal (including human) bodies to sample and deliver fluids. Although some applications need only short-term catheterization, many applications--for example, sampling or delivering fluids during experiments, tests, or therapies--require long-term or "chronic" placement of the catheter within a body. As is recognized by those of skill in the art, the migration of a catheter can ruin chronic experiments or therapies. For example, the study of biological activities or properties of new pharmaceuticals in experimental models often requires chronic sampling of the central nervous system fluid. To collect scientifically valid samples during this type of research, the catheter used to sample the fluids must not migrate or change position so that samples are withdrawn from the same point within the body.
Previous attempts to minimize migration of an indwelling catheter include attaching the catheter with screws and wire to bone. However, this attachment method can cause the catheter to wear out about the fixation point during body movements. Further, this method requires a painful, invasive procedure: the dissection of muscle to expose the bone for catheter attachment.
Other attachment methods, such as fixing the catheter in the subcutaneous tissue with discs and purse string sutures, either permit an undesirable amount of movement of the catheter or only maintain the catheter in place for short periods.
A variety of catheter and other medical devices have been designed for short-term and long-term insertion in a body. For example, U.S. Pat. No. 5,454,795 to Samson entitled "Kink-Free Spiral-Wound Catheter" issued Oct. 3, 1995 discloses a catheter for introduction to the vascular system in angioplasty procedures. A polymeric tube is spirally wound with "ribbons" to control the stiffness of the catheter. However, Samson discloses a catheter that slides smoothly through the vascular system rather than fixate in tissue for chronic use.
U.S. Pat. No. 3,399,668 to Lundgren entitled "Disposable Cholangiography Catheter" issued Sep. 3, 1968 discloses a disposable cholangiographic catheter for use in open abdominal surgery. The catheter has an exterior surface friction portion that cooperates with a tying element to prevent movement of the catheter in the bile duct. The friction portion can include ridges and depressions, a roughened abraded area, an adhesive layer on which fine grains of sand are permanently affixed, a tacky adhesive layer, or an adhesive that dries with a fine granular surface. However, to prevent catheter movement, the Lundgren catheter requires a tying element surrounding the cystic duct in which the catheter is inserted. This catheterization system thus necessitates an invasive and awkward surgical procedure for installation.
U.S. Pat. No. 4,955,859 to Zilber entitled "High-Friction Prosthetic Stent" issued Sep. 11, 1990 discloses a urethral stent for the non-surgical management of bladder outlet obstruction caused by an enlarged prostate. The stent includes either a textured fabric outer layer bonded to the tubular body of the stent or a silicon rubber outer jacket with a roughened outer surface. However, Zilber is directed to managing bladder obstructions, and thus fails to provide a fixating system for chronic access to deliver and sample fluids.
U.S. Pat. No. 4,266,999 to Baier entitled "Catheter For Long-Term Emplacement" issued May 12, 1981 discloses a catheter having a roughened exterior surface suitable for tissue ingrowth to provide adhesion between the skin and the roughened surface. However, the Baier catheter system fails to provide means of preventing migration of the catheter prior to tissue ingrowth.
U.S. Pat. No. 3,638,649 to Ersek entitled "Implantable Prosthetic Pass-Through Device" issued Feb. 1, 1972 discloses a catheter that allows skin tissue to form a permanent seal by using a tube having a roughened portion comprising "a myriad of hairy projections." Again, Ersek fails to provide a means of preventing migration of the device prior to tissue ingrowth.


A gas laser design (10) includes, an elongated sealed tube (21) filled with a gas, a power supply for exciting the gas, an optical resonator (24,25) for producing directional optical energy, and a fan/electronics package assembly (50), all of which are surrounded and enclosed by an external housing (30,70,90) forming a passageway in the space between the tube and the housing for providing cooling air therethrough. The passageway is divided into two physically separated cooling air paths by a horizontal surface (21a or 41). The lower space is a dual L-shaped path defining the first cooling air path downwardly at the inlet end of the tube in the vertical air channels (31,32) formed by the contoured shape of the tube and rearwardly (33) through the spaces (27,29) between the horizontal fins (26,28) of the tube to an outlet (101) at the rear of the tube. The upper space defines the second cooling air path from the inlet end of the tube horizontally rearwardly (64) around and over the electronics package (50) mounted in that portion of the passageway in a U-shaped finned heatsink channel (53), through the spaces (61,63) between the fins (62,64) to the atmosphere at the rear end. The zone (44) under the fan (52) is common to both cooling air paths. All components related to air cooling are enclosed within the outer housing forming a compact, high power, thermally stable, gas laser assembly.

1. Fields of the Invention
The present invention relates generally to an apparatus and method for air cooling a gas laser tube, especially of the waveguide, free-space, and, more recently free-space gas slab laser varieties, and, more particularly, to a forced air system in which an air passageway between the outside of an extruded, elongated, contoured and finned gas laser tube and the inside of a housing enclosing the tube is divided into two, separate cooling air paths, the first path being an L-shaped path for cooling the finned tube, and the second path being for cooling an electronics package mounted in a U-shaped heatsink channel in the second path, and, which is efficiently arranged in a small, compact package.
2. Discussion of Background and Prior Art
a. Controlled Thermal Environment
Due to the intense heat generated within gas laser tubes, and the continuing development of new and better gas lasers, maintaining a controlled thermal environment for the gas laser tube continues as a major problem for laser manufacturers despite many solutions for various aspects of the problem over the years.
(1) Balanced Cooling
One aspect of the problem of maintaining a controlled thermal environment in a gas laser is to provide a cooling system which efficiently and effectively dissipates the heat. In such systems, it is also important to remove the heat in a balanced manner proportionally to the rate at which it is developed in various locations around the tube in order to maintain a uniform thermal environment. This need is especially important in elongated gas lasers where preventing bending moments from uneven heating and cooling is critical in maintaining predetermined electrode spacing in the discharge area for efficient lasing, predetermined electrode-to-housing spacing for meeting designed capacitance parameters and impedance matching characteristics, and torsion free longitudinal expansion of the electrodes within the tube resonator alignment. Accordingly, it is an object of the present invention to provide an elongated but compact gas laser in a small package to meet the above criteria.
(2) Simultaneously Cooling the Tube Itself and Associated Electrical Components
Of primary concern is to cool the gas laser tube itself since the laser plasma formed inside the tube in the discharge area is the primary source of heat emanating from the tube. However, additional heat is also supplied by associated electrical or electronic components and that heat must also be dissipated uniformly and proportionately.
In an air cooled system by Chaffee in U.S. Pat. No. 5,253,261 a cooling air flow is provided in an annular space between a cylindrical gas laser tube and an outer cylindrical housing by a pair of centrally located suction fans creating a cooling air flow through a solenoid and out of the housing. The air is drawn into the tube in opposite directions through air channels between the tube and electrical solenoid assemblies surrounding the tube and exits centrally of the solenoids through the suction fans, the air in each channel simultaneously cooling the tube and the electrical solenoids surrounding the tube. However, Chaffee does not disclose, and it is an object of the present invention to provide, a cooling air system for gas lasers having parallel, spaced-apart, elongated electrodes with a cooling air path which is divided into two separated paths, one for cooling a contoured, finned tube, and the other for cooling a finned heatsink electronics package.
In a system to Hiroshima in U.S. Pat. No. 5,251,223 an air cooled argon ion laser tube is disclosed in which air from a fan mounted on the outside of a cover surrounding the tube and over radial fins to cool the tube located in the same chamber adjacent a hot cathode bulb. A problem with Hiroshima is it does not uniformly dissipate heat in a balanced manner. Accordingly, like Chaffee, Hiroshima does not disclose, and it is an object of the present invention to provide, a cooling air system for an elongated gas laser of the waveguide, free-space or free-space slab varieties wherein the fan is mounted inside of the outer cover driving air through two separated, divided paths to simultaneously cool the tube and an associated electronics package while dissipating heat from both areas in a uniform, balanced manner.
Finally, in an approach by Das in U.S. Pat. No. 5,586,134 the electronics components generating voltage pulses applied to the cathode of an excimer laser are air cooled (FIG. 10) by a forced air system in which the cool air flows past a thyratron and around a chimney and trigger board, all in the space between the laser housing and an outer cover, and the heat is removed from the cooling air in an external water cooled heat exchanger. However, Das's system for cooling the tube itself uses a flow path of the laser gas cooled separately by a water cooled heat exchanger inside the tube. Accordingly, it is an object of the present invention to simultaneously air cool the laser tube and the electronics package by providing divided paths totally within the passageway between the tube and the outer cover in a small, compact package.
Further objects and advantages will be apparent from the summary and detailed description of the present invention which follows.


An image processing apparatus capable of automatically adjusting the enlargement ratio and the position of images and to display the noticed areas of all selected images is disclosed. When a two image display mode is selected, an image previously displayed (a first image) and an image to be displayed in the two image display mode (a second image) are loaded from a memory into a display controlling unit and a correction value calculating unit. The display controlling unit performs enlarging and moving operations with respect to the first image and the second image simultaneously. The correction value calculating unit searches for an area in the second image (a corrected area) most resembling an enlarged area in the first image so as to enlarge the corrected area in the second image. The images processed by the display controlling unit are transmitted to an image display memory.

1. Field of the Invention
The present invention generally relates to a digital image processing apparatus, and more specifically to a technique preferably adapted to software for a printer, a facsimile machine, a digital camera, a personal computer, and the like.
2. Description of the Related Art
Recently, the image resolution of image input devices such as a flat bed scanner and a digital camera has been remarkably improved. However, the image resolution of display devices displaying the images input by such input devices is not so high as that of the input devices. For example, there are so many digital cameras having resolutions of 4 through 5 million pixels, but the resolutions of liquid crystal displays for personal computers are still 1.3 million pixels for SXGA and 2 million pixels for UXGA. Further, the resolution of a liquid crystal display attached to a digital camera is even lower. As a result, the resolution of an image input by an image input device needs to be reduced when viewed on a display.
Unfortunately, when the image is viewed with reduced resolution, necessary information may not be obtained in many cases. For example, a case where a picture of a person is taken with a digital camera is considered. When pictures are taken, plural same pictures may be taken to get a best shot. However, in typical use of such a digital camera, since the data storage capacity of the camera is limited, the user is more likely to delete some unnecessary plural pictures when the capacity is running out. In this case, the user may view the attached liquid crystal display to select pictures to be deleted. Unfortunately, there may be many cases where the eyes of the person are closed when the pictures are viewed on a display of a personal computer. To avoid such problems, there may be a method of enlarging a part of a picture that has been shrunk. However, there is a problem that it is very troublesome to perform the same operations of enlarging and moving with respect to plural pictures.
To solve the problem, Patent Document 1 discloses a technique in which selected plural images are displayed on the same display; when enlarge, shrink, and move operations are performed on one of the plural pictures, the same operations are also applied to the other pictures displayed on the display. By doing this, it is possible to determine whether the eyes of the person are closed with fewer operations. In addition, it is not to hard to anticipate that this technique of Patent Document 1 is useful when applied to a document image scanned by a flat bed scanner. For example, when this technique is applied to document images viewed as the same document when viewed in a list in a thumbnail grid mode, it is possible to effectively view a selected part of each document where important information is included.
Patent Document 1: Japanese Patent Application Publication No. 2006-5640
Non Patent Document 1: 1C. Cortes and V. N. Vapnik "Support Vector Networks," Machine Learning, vol. 20, pp. 273-297, 1995
Non Patent Document 2: N. Otsu, and T. Kurita, "A new scheme for practical, flexible and intelligent vision system," Proc. IAPR Workshop on Computer Vision, pp. 431-435, 1988.
However, it is not necessarily the case that all the document images scanned by a flat bed scanner have exactly the same layout.
As an example, FIGS. 1A through 1D illustrate such a case where a snapshot (picture) of a person is taken. FIG. 1A is a first picture of the person. As shown in FIG. 1A, the person is displayed in the center of the picture. FIG. 1B is an enlarged image of the area surrounded by the rectangle in FIG. 1A. After a few seconds, a next picture is taken to get a best shot. FIG. 1C is a second picture of the person. As shown in FIG. 1C, the person is moved to the left-hand side of the picture. Now, FIG. 1D is another enlarged image of the area surrounded by the rectangle in FIG. 1C. The positions of the rectangles in FIGS. 1A and 1C are the same with respect to the corresponding pictures. As a result, as shown in FIG. 1D, the face of the person is not included in FIG. 1D. In such a case like this, it is necessary to slightly adjust the enlarged (noticed) area so as to see the face of the person as shown in FIG. 1B. As described, there may be cases where necessary information is not included in the same noticed areas when the position is slightly moved among plural pictures.
The above case may be relatively extreme because the person is moved a large distance from the center position, and the above case may not be likely to occur in a typical photo shoot. However, when an enlargement factor is large, that is, when the noticed area is relatively small compared with the original image including the noticed area, the same problem as described above may occur. For example, a display device attached to a typical digital camera is very small. Therefore, to check an image on the display device carefully, the image is required to be sufficiently enlarged. As another example, there may be a case where the face of a person is very small when, for example, a group of people are included in a picture. In such a case, it is also required to sufficiently enlarge the necessary area of the picture. When these cases are considered, a camera shaking in a photo shoot may become a serious mistake in the photo shoot.

Image processing apparatus, image processing method, program, and recording medium