A retractable nail includes a head portion having a striking surface and a slot through the striking face. The slot is configured for receiving a removal tool. The nail includes a piercing part the head portion and the piercing part. A longitudinal main body is positioned between the longitudinal main body includes a front side, rear side and two lateral sides. The front and rear sides include respective front and rear helical thread segments formed along a longitudinal length of the main body. The threads are filled or covered with a plastic material, epoxy, glue, composite or the like to prevent damage to the helically threads when the device is hammered or bored with a pneumatically or electrically powered nail gun into a solid material.

1. Field of the Invention
The present invention relates to a retractable nail device, more particularly to an attachment device to any solid, fibrous or cellular materials or the like, including wood, metal, plastic or composite materials, which can be retracted without destroying the material to which the retractable nail device is inserted into. In particular, the helically threaded portions of the device are covered or filled with a plastic material, epoxy, glue, composite or the like to prevent damage to the helically threaded portions of the device when the device is hammered or bored with a pneumatically or electrically powered nail to any solid, fibrous or cellular materials or the like, including wood, metal, plastic or composite materials.
2. Description of the Related Art
The wood floor nail 3 of FIG. 12 and the wood floor staple 13 illustrate prior art attachment devices that are used to attach wood floor boards to the sub floor, in the manner similar to the illustration of FIG. 11. The wood floor nail 3 has a main head 30 and a main body 32, lateral extensions 34 on front and rear sides of the main body 32, and a tip 35. The wood floor nails 3 are generally placed in a magazine clip attached to a pneumatically or electrically powered nail gun. The nails 3 are readily inserted into wood floor boards, with the main head 30 anchored to an outer surface of the wood floor board, but the nail 3 can not be easily removed. In the event that one has mistakenly inserted the nail 3, there is no easy means of removing the nail 3. Somehow the main head 30 must be grasped and pulled, causing damage to the delicate wood floor board, and the lateral extensions 34 that act to retain the nail 3 into the wood floor board and sub floor will destroy or at least significantly damage the wood floor board, as well as the sub floor when the nail 3 is pulled out. The lateral extensions 34 are not part of any helical screw thread and therefore, rotation of the nail 3 will not form a screw bore/helical thread bore that would permit the escape of the nail 3 out of the wood floor board and sub floor without significant damage to the wood material.
The wood floor staple 5 of FIG. 13 is also used to attach wood floor boards to a sub floor. The staple 5 includes a pair of legs 55 and a connector 52 connected to the legs 55. The staples 5 are usually placed in a magazine feed attached to a staple gun and the legs 55 are stapled into the wood floor board and sub floor, in a manner similar to the nail 1 shown in FIG. 11. The connector 55 rests on the wood floor board at a location similar to the main head 10 of the nail 1 in FIG. 11.
The problem with the staple 52 is that the connector 52 tends to strongly impact the wood floor board, often shearing off pieces of the wood floor board on impact and thereby destroying the wood floor board. The use of a staple gun is not recommended when using brittle wood material or expensive materials, such as aged wood or the like. The staples 5 are easily dispensed but in addition to the disadvantage mentioned above, the staples 5 can not be readily or easily removed. If the staple 5 is applied incorrectly, the connector 52 must somehow be grasped and pulled to try to remove the staple. This is a highly time-consuming process which may lead to irreparable damage to the wood floor board.
Ordinary screws (not shown), such as wood screws, have a helical thread that spirals from at or near the piercing tip towards the head portion along its longitudinal length around a main body or shaft, as in the wood screw of U.S. Pat. No. 4,572,720. Such screws generally have a tool receiving slot for receiving a retracting tool such as a Phillips head screw head, Allen wrench, or the like, and are attached to a material by using a power tool that rotates the retracting tool which has been inserted into the tool receiving slot of the screw head. A helical threaded bore is formed in the material when the screw is inserted via rotation thereof. Such procedure also enables the screw to be retracted (via counter-rotation, leaving behind the helically threaded bore) without any significant damage to the material such as a wood floor, but the insertion by screw rotation of individual screws is highly time-consuming and labor-intensive, which significantly adds to overall building costs, i.e. laying wood flooring.
Furthermore when ordinary wood screw is driven into a wooden board, it is known that the wood shavings fill the grooves formed between adjacent screw thread sections on the shank portion as the screw threads cuts into the fibers of the wooden board, thereby resulting in a binding force between the screw and the wooden board. However, because the cutting line is in the form of a smooth spiral line, the cutting effect of the screw thread becomes duller as the cutting effect of the screw thread becomes duller as the depth of penetration of the conventional wood screw into the wood board increases. In addition, the increased resistance can have adverse affect on the required screw driving force and can result in possible damage to the screw.
Therefore, there is a need for an attachment device that can be quickly and easily be inserted into wood material or similar materials (i.e. via a nail gun), but which can be removed without significantly damaging or destroying the material while maintaining the integrity of the helically threaded portion of the device.


The present invention relates to new 3-[4-(2-Phenyl-Indole-1-ylmethyl)-Phenyl]-Acrylamide compounds which are useful as estrogenic agents, as well as pharmaceutical compositions and methods of treatment utilizing these compounds, the compounds having the following general structure. ##STR1##

The use of hormone replacement therapy for bone loss prevention in post-menopausal women is well precedented. The normal protocol calls for estrogen supplementation using such formulations containing estrone, estriol, ethynyl estradiol or conjugated estrogens isolated from natural sources (Premarin from Wyeth-Ayerst). In some patients, therapy may be contraindicated due to the proliferative effects unopposed estrogens (estrogens not given in combination with progestins) have on uterine tissue. This proliferation is associated with increased risk for endometriosis and/or endometrial cancer. The effects of unopposed estrogens on breast tissue is less clear, but is of some concern. The need for estrogens which can maintain the bone sparing effect while minimizing the proliferative effects in the uterus and breast is evident. Certain nonsteroidal antiestrogens have been shown to maintain bone mass in the ovariectomized rat model as well as in human clinical trials. Tamoxifen, for example, is a useful palliative for the treatment of breast cancer. It has been demonstrated to exert an estrogen agonist like effect on the bone, in humans. However, it is also a partial agonist in the uterus and this is cause for some concern. Raloxifene, a benzothiophene antiestrogen, has been shown to stimulate uterine growth in the ovariectomized rat to a lesser extent than Tamoxifen while maintaining the ability to spare bone. A suitable review of tissue selective estrogens is: Tissue -Selective Actions Of Estrogen Analogs, Bone Vol. 17, No. 4, October 1995, 181S-190S.
The use of indoles as estrogen antagonists has been reported by Von Angerer, Chemical Abstracts, Vol. 99, No. 7 (1983), Abstract No. 53886u. Also, see, J.Med.Chem. 1990, 33, 2635-2640; J.Med.Chem. 1987, 30, 131-136. Also see Ger. Offen., DE 3821148 A1 891228. Additionally, see WO, A, 93 23374 (Otsuka Pharmaceutical Factory, Inc.). Von Angerer's work is limited to aliphatic chains linked to the indole nitrogen and then linked to the basic amine (or amide) or, benzyl groups not possessing the basic amine. The world patent from Otsuka (Japanese) consists of compounds related to the present invention except R.sub.3 (as shown in formula I) is defined as --SR where R is alkyl. Additionally, there are no chains from the indole nitrogen in their patent with the same structure as the ones given in the present invention, either by claim or example. A related patent WO A 93 10741 describes 5-Hydroxyindoles. WO A 95 17383 (Kar Bio AB) describes aliphatic chain compounds.

3- [4- (2- Phenyl-Indole-1-ylmethyl) Phenyl]- Acrylamides as estrogenic agents


A phase shifter component is described. Inputs are arranged to selectively receive an inphase component of an in-phase (I) signal or an outphase I signal 180° out of phase with the inphase I signal, and to selectively receive an inphase component of a quadrature-phase (Q) signal or an outphase Q signal 180° out of phase with the inphase Q signal. A first gain portion includes only two transistor elements arranged to amplify the received outphase or inphase I signal. A second gain portion includes only two transistor elements arranged to amplify the received outphase or inphase Q signal. The first and second gain portions are configured to control the gain of the received outphase or inphase I signal and the received outphase or inphase Q signal, respectively, to provide a composite output signal with a desired phase shift between 0° and 360°.

The present disclosure relates generally to phase shifter topology. More particularly, the present application relates to a phase shifter topology that may be used in an electronically scanned array (ESA) and in other devices that require precision phase control.
In known phase shifter topology, the phase shifter divides the amplified signal from a variable amplitude controller into an in-phase (I) signal and quadrature-phase (Q) signal. The variable amplitude controller provides amplitude shaping of the signal, while the quadrature phase shifter provides for 0-180° quadrant control for the I and Q signals to achieve full 360° control. In this topology, the quadrature phase shifter has two sets of transistor pairs for the I input to create the differential in-phase signals I+ and I−, and two sets of transistor pairs for the Q input to create the differential quadrature-phase signals Q+ and Q−, for a total of eight transistors.
For the eight transistor phase shifter design, the necessity to perform the 0-180° quadrant control for the I and Q signals requires additional voltage overhead due to vertical transistor stacking. Further, the necessity to perform the outphase of the I and Q signals requires extra parasitic loading on the inputs, because only two of the four transistors in each cell are actively biased on at any point depending on the quadrant selected.


A circuit in which the source-to-drain conduction path of a power switching transistor is connected in series with an inductive load between first and second power terminals includes a voltage transient clamping transistor having its source-to-drain conduction path connected between the drain and gate of the switching transistor. In response to a turn-off signal applied to the gate of the switching transistor, a transient voltage is generated at the drain of the switching transistor. When the transient voltage at the drain of the power switching transistor exceeds a predetermined value, the clamping transistor is turned-on. The conduction of the clamping transistor limits the voltage rise at the drain of the switching transistor and tends to maintain the switching transistor conducting temporarily to aid in the discharge of the energy stored in the inductive load. A unidirectional conducting element connected in series with the clamping transistor ensures that only current of a polarity to discharge the inductive load flows through the clamping transistor.

This invention relates to circuitry for protecting a transistor against excessive transient voltages developed across the transistor such as when the transistor drives an inductor.
It is known to use an insulated-gate field effect transistor (IGFET) power transistor to drive an inductive load. As shown in FIG. 1, a metal-oxide-semiconductor (MOS) power switching transistor N1 has its conduction path connected between ground terminal 15 and a node 17. An inductor L1 connected in series with a resistance Rs is connected between node 17 and a power terminal 19 to which is applied a source of operating potential of VCC volts. The resistor Rs shown connected in series with inductor L1 may be a discrete current limiting resistor, or the inherent resistance of the inductor, or may represent a combination of both. When the transistor N1 is turned-on the current through the inductor increases with time, and when N1 is on for a period of time which exceeds the inductive-resistance time constant (T=L1/Rs), the current through the inductor L1 approaches a value of IMAX=VCC/Rs. When transistor N1 is turned-off, after being turned-on for any significant period, the electromotive force of the inductor attempts to maintain the current flow by generating a voltage which results in what is known in the art and referred to herein as an "inductive kick". The value of the voltage generated across the inductor is equal to Ldi/dt and has a polarity to raise node 17 above the positive power supply, where L is the inductance of the inductor (coil) and di/dt is the time rate of change of the decay current. The amplitude of the inductive kick voltage may range up to several hundred, and even thousands of volts. This high voltage kick at node 17 may exceed the breakdown voltage (BVDS) of the transistor N1 causing the transistor to be damaged and/or destroyed and also causing damage to associated circuitry. Therefore, the voltage at the drain of N1 must be limited to avoid exceeding the break down voltage of N1 and the generation of high amplitude transient voltages.
A known method for limiting the voltage due to an "inductive kick" includes the use of a "load dumping" diode such as diode D1 connected at its anode to node 17 and at its cathode to terminal 19. So connected, the voltage at node 17 can rise to one forward diode drop (VF) above VCC. The diode D1 functions to limit the voltage kick at node 17 to VF+VCC and the voltage across the inductor-resistor combination is limited to VF volts (typically 0.8 volts). Limiting the voltage across the inductor-resistor to such a relatively small value (i.e., VF volts) effectively limits the inductive kick, but as a result it takes a relatively long time to discharge the energy stored in the inductor. The ideal discharge (or decay) time (TD) of an inductor with zero resistance is equal to L(IND)/VL; where L is the inductance of the coil, IND is the-current in the inductor at the time N1 is turned-off, and VL is the voltage drop across the inductor. Thus the discharge time is inversely proportional to the voltage across the inductor. Also, the diode must be made very large to handle the maximum inductive current which may equal VCC/Rs.
To avoid the problems present when using a single diode, it is known to use a Zener diode (Z1) and a diode (D2) serially connected between the drain and gate of power transistor N1 as shown in FIG. 2. Referring to FIG. 2, it should be noted that, as in the circuit of FIG. 1, after N1 is turned-on for some time a substantial current flows through L1 and via the conduction path of N1 to ground. Typically N1 will be turned-off by the turn-on of transistor NA in inverter I1 which tends to clamp the gate of N1 to ground. When N1 is turned-off at a time t1, the voltage at node 17 tends to rise sharply. When the voltage (V17) at node 17 rises above the forward drop (VFD2) of D2 and the Zener voltage (VZ) of Z1, conduction takes place from node 17 via D2 and Z1 into the gate of N1. As a result, V17 will be held at a value equal to the VFD2 of D2 plus the VZ of Z1 above the voltage (V13) at the output 13 of inverter I1. Typically, V13 will be maintained a little above the threshold voltage (VTH) of N1, which is within a volt or so of ground potential. Thus by selecting VZ+VFD2+VTH to be less than the breakdown voltage of N1, the voltage at node 17 is prevented from exceeding the breakdown of N1.
Limiting or clamping the voltage at node 17 using Zener diode feedback as shown in FIG. 2 is advantageous in that the Zener diode voltage can be selected to control V17 to be less than the drain-to-source and drain-to-gate breakdown voltage of N1. Furthermore, it provides a larger amplitude turn-off voltage across the inductor which results in the current in the inductor being discharged much faster. Furthermore, most of the inductive load dump current flows through power transistor N1, whereby the Zener diode can be made to be a low current structure.
However, a problem exists in that it is not always possible to make a zener diode with the required zener breakdown voltage and/or needed characteristics. Moreover, in some processes it is not even possible to make a zener diode within the same structure as the MOS power transistor.
To overcome this problem, an object of the present invention is to use a "clamping" transistor to clamp any transient voltage produced at the drain of the power switching transistor instead of a zener or diode clamp.


A clockless time-of-flight interval timer includes a tapped delay line register comprising N buffers that each contribute a substantially identical incremental time delay. A latched version of a START pulse associated with an output of transmitted energy from a laser is propagated through the tapped delay line. A DATA signal representing a detected pulse returned from a target is coupled to a block of four comparators each having a different signal threshold. The output of each comparator block is provided as input to one of four channel registers, each register comprising N D-type flipflops separately but synchronously triggerable by tapped incrementally delayed outputs from the N buffers. Channel register outputs are multiplexed and decoded and interfaced with a microprocessor. The microprocessor determines first signal time over threshold (FOT) information and total time over threshold (TOT) information from the channel registers. The FOT provides a measure of time-of-flight, which measure can be corrected using TOT information and a look-up table containing timing walk incremental delay corrections for individual ones of the N buffers. TOT information can be used as an indicator of signal strength and thus may be used to correct for systematic errors in measured delay, which arise from fluctuation in signal strength.

The present invention relates generally to timing systems to measure short time intervals, and more particularly to timing systems suitable for time of flight pulse measurements such as found in systems used to guard protected equipment.
In many applications it is necessary to know the distance between two points. Although knowledge of distance per se can be used to make a range finder, in other applications knowledge of distance can be used to protect a zone against intrusion. A factory may have robotic or potentially hazardous equipment that is to be protected from outsiders. A system that can measure the distance between such equipment and a perimeter region around the equipment can sound an alarm or turn-off the equipment if anyone approaches closer than the periphery of the protected zone. In this fashion, outsiders are protected against harm from the equipment, and any operators using the equipment are protected from harm by being startled or otherwise disturbed by outsiders.
FIG. 1 depicts a generic so-called time-of-flight system 10 used to calculate the distance X between system 10 and a target (TARGET). System 10 may be located adjacent robotic or perhaps hazardous machinery in a factory where an alarm is to be sounded or the machinery turned-off if anyone approaches closer than distance X.
Typically system 10 includes a trigger generator 20 that creates a pulse train that is input to a transmitter (XMTR) 30, such as a high speed laser, that broadcasts a pulse via a suitable lens 40. The broadcast pulse 50 radiates outward at the speed of light, and at least a portion of the radiation may contact the surface of the target, and be reflected back toward system 10. The reflected-back radiation 55, which also travels at the speed of light, is detected by an appropriate transducer 60 (e.g., an optical lens) and photodetector 70. In a zone protection application, a mirror within system 10 mechanically rotates in a plane such that transmitted pulses scan the protected region, and return pulses are detected from this region. The protected region may be defined as a swept arc centered on the equipment to be protected, and extending outward with a radius of at least X. Typically the laser transmitter is triggered or pulsed with a known frequency in synchronism with mirror rotation such that detected return pulses can be correlated with an angle of emission, to locate the angular position and range of the intruding object. In such applications, any target (TARGET) within range X within the swept protection zone is presumed to be an intruder. Note that X may be a function of scan angle in that the guarded perimeter need not be defined by a swept arc.
As indicated in FIG. 1, there will be a phase or time shift between corresponding portions of the radiating pulse energy 50 and the return or reflected back radiation 55. Thus, at time t0 a first radiated pulse transitions 0-to-1, but the same pulse upon detection (denoted now P1xe2x80x2) will have its leading edge transition 0-to-1 at time t1+Tw later than t0. A high speed counter logic unit 80 within system 10 then attempts to calculate the difference in time between t1+Tw and t0. Tw is a signal strength dependent term that is sometimes called xe2x80x9ctiming walkxe2x80x9d.
Within unit 10, detected return pulse Pxe2x80x2 is amplified and coupled to a comparator to determine the return pulse transition timing. Return pulse transition timing is typically dependent on the strength of the return pulse, which in turn is determined by object reflectivity and range. In FIG. 1, T1 is the delay corresponding to the physical separation between system 10 and the object or target, whereas Tw is the timing walk strength dependent term.
Typically unit 80 includes a high speed master clock 85 (CLK) and a high speed counter 90 (COUNT). At time t0, as determined by a START pulse associated with the beginning of an output emission 50, counter 90 begins to count clock pulses. At time t1+tw, when pulse P1xe2x80x2 is detected, counter 90 is halted upon receipt of a STOP pulse, and the count value is determined.
Typically Tw is strongly dependent upon the signal response of the transmitter and receiver circuitry and must be characterized. Correction values are determined over a range of P1xe2x80x2 signal strengths and are stored in a table. The values stored in the correction table are indexed by detected signal strength and may be used by a system control circuit to extract the value t1. Thus, prior art systems that employ time-interval counters typically will use a peak-detector or signal integrator.
Once t1 is known, a measure of distance x given At xcex94t=(t1xe2x88x92t0) is determined by the following equation:   x  =                    c        ·        Δ                          xe2x80x83                  t        2
where c=velocity of light (300,000 km/sec).
Within system 10, generating, transmitting, and receiving pulses can be straightforward. But it can be challenging for system 10 to resolve the distance X within a desired measurement granularity or tolerance. For example, to measure distance with a resolution granularity of about xc2x15 cm requires a 3 GHz counter. Such high speed devices are expensive and typically consume several watts of electrical power.
An alternative approach would be to replace the function of high speed clock 85 and high speed counter unit 90 with a high speed analog-to-digital converter. However high speed analog-to-digital converters are relatively expensive.
Yet another approach would be to replace units 85 and 90 with a transient recorder, perhaps inexpensively implemented using common CMOS fabrication processes. Transient recording could be extremely fast yet would not consume excessive electrical power. One prior art transient recorder technique is described in a Univ. of Calif. At Berkeley 1992 M. Sci. thesis entitled xe2x80x9cA Multi-Gigahertz Analog Transient Recorder Integrated Circuitxe2x80x9d by S. A. Kleinfelder. Kleinfelder""s thesis described a tapped, active delay line using an array of storage capacitors. The capacitors stored samples of the detected return pulse P1xe2x80x2 at specific delay times that were set by the delay of each element in the delay line.
Keinfelder""s approach appears ideal in that it presents a fully digitized representation of the delayed pulse (or multiple pulses), at relatively minimal cost. Further, no thresholding of the analog return pulse is necessary, and range distance may be computed using an algorithm that takes into account the full pulse shape. The latter is important in determining target range, independently of the strength of the return pulse P1.
Unfortunately, in practice Kleinfelder""s system is difficult to implement because of the large amount of data that must be processed in a relatively short time. Further, it is necessary to characterize performance of the active delay line and particularly the storage capacitors and analog-to-digital converter circuitry over process, temperature, and voltage variations.
What is needed is a high speed time interval measurement system for use in applications such as time-of-flight systems, especially in systems used to guard machinery or the like. Such measurement system should be inexpensive to fabricate, preferably using existing CMOS processes, should exhibit low power consumption, and should provide timing and strength information for one or more return pulses. Such measurement system should rapidly detect multiple return pulses, preferably within time intervals of less than about 500 ns, with a sub-nanosecond timing resolution that can provide spatial resolution of xc2x15 cm or less. Further, the system should measure return pulse signal strength with sufficient precision for use as an index to a lookup table to correct for timing walk. The system should communicate range measurements with a minimal amount of data. Finally, the system should exhibit reduced sensitivity to variations in ambient temperature, operating voltage, and fabrication processes.
The present invention provides such a high speed measurement system.
The present invention provides a high speed time interval system to measure time intervals xcex94t in time-of-flight measurement systems, preferably for use in systems that guard the perimeter of machinery or the like. The system measures time interval between a transmitted scanned laser pulse and a return pulse to determine distance, and can be fabricated on an integrated circuit (IC) using generic components. But unlike prior art systems, the system also returns a measurement of the width of the detected return pulse. Such information is used as indices to a lookup table that stores time walk corrections to the measured range distance. Knowledge of the return pulse width permits inferring strength of the return pulse, which inferred strength is used to estimate time walk Tw. Time walk Tw represents systematic error arising in raw range measurement due to fluctuations in detected signal strength and timing uniformities, the latter arising from process-dependent effects. The IC comprising the present invention is realizable with relatively inexpensive CMOS fabrication processes such that multiple data inputs may be incorporated into the IC without incurring significant additional cost.
The present invention is used with a zone protection system that includes a laser transmitter and photo detector that together define a coaxial field of view. A motor and mirror assembly cause emitted laser pulses and the detector field of view to scan a two-dimensional protection zone. The laser is pulsed with a specified frequency and in synchronously with motor-mirror rotation. A reference target is disposed within the zone protection system housing to reflect a portion of the transmitted energy back to the photo detector for use in compensating the present invention against system thermal drift.
In making time measurements, the present invention eliminates high speed clocks and high speed digital counters such as are commonly employed in prior art time-of-flight measurements. Instead, the present invention derives a START pulse from the laser drive signal (LASER START). This pulse is input to a latch whose output signal is propagated through a tapped delay line portion of a tapped delay line register (TDLR). The tapped delay line comprises preferably 512 buffers that each contribute an incremental time delay to the latch signal.
The detected return pulse is coupled to a bank of comparators (e.g., four comparators denoted CH0, CH1, CH2, CH3) that test the pulse against different threshold magnitudes. The comparator bank output signals are input to the TDLR, namely to individual channel registers that are also coupled to the preferably 512 delays from the tapped delay line register. The TDLR also receives the detector signal returned from the reference target. The TDLR is coupled to a microprocessor for readout, the microprocessor having access to a look-up table (LUT) that contains timing walk information that can be used to correct system errors.
The latched START pulse functions as a clock signal for the TDLR and clocks the detection data output from the comparator bank. The START-clocked TDLR, which preferably has four data inputs, functions in a manner similar to a two-bit transient recorder that clocks synchronously with the LASER START signal and can provide four signal values. For each data channel, the TDLR outputs a first over threshold (FOT) signal proportional to the rising edge of the first detected return pulse. FOT may be treated as the first 0-to-1 transition of the detected pulse signal. The FOT enables the microprocessor to provide a measure of time delay and thus of distance X to the target that returned the detected pulse. By itself the FOT can thus serve to approximate distance X. However the TDLR further determines and outputs a total time over threshold signal (TOT) that is proportional to how long the detected pulse energy exceeded a threshold. The TOT may be considered as how long the detected signal, after transitioning 0-to-1 remains at 1 before transitioning from 1-to-0. The TOT information permits the microprocessor to infer strength of the returned pulse, including rising and fall transition slopes and pulse width. The inferred strength information is used to index previously stored timing correction information in the look-up table. Such timing correction information will have been obtained during the system design by examining timing walk behavior of the system. The look-up table permits correction, as needed, to the FOT information. Further, the elimination of high speed clocks and high speed counters permits the system to be battery operated and fabricated as a single integrated circuit.
Other features and advantages of the invention will appear from the following description in which the preferred embodiments have been set forth in detail, in conjunction with the accompanying drawings.


A system for monitoring and reporting of alarm events occurring in a monitored system includes a power supply, a switch module, an alarm interface, an event message module and a system controller wherein the switch module provides active power to the event message module, the wireless communication module and the system controller only when an alarm event is detected.

The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
The present disclosure is particularly well adapted for implementation in securing agricultural irrigation systems such as a pivot move system described in U.S. Pat. No. 3,669,353, the entirety of which is incorporated herein by reference.
Pivot move systems include a radial arm which traverses a field being irrigated in a circular arc while sprinklers, positioned along the arm, irrigate the field. The pivot arm moves about a center point with the arm extending a significant distance, which can be several thousand feet. At the pivot point, electrical and electronic controls are located, together with a gas generator to power the system.
As illustrated in FIG. 2 and FIG. 3 of U.S. Pat. No. 3,669,353, wheeled ground engaging assemblies support the radial arm at spaced locations. The wheel speed of each assembly must be synchronized for correspondence because the wheels closer to the pivot rotate at a slower speed than the wheels progressively spaced from the pivot and traverse proportionately smaller distances.
A wiring harness extends the length of the arm and includes lines extending to each of the ground engaging assemblies for powering motors which drive the wheels, lights, water pumps, etc.
Because the irrigation systems are positioned in remote areas without supervision, security systems are employed to guard against vandalism and theft, including theft of the electrical wiring harness.
The wiring harness includes a closed loop to monitor the movement of the wheels for the purpose of shutting down operation in the event a wheel encounters an obstacle and is blocked from rotation.
In order to monitor the wheels, switches are provided adjacent each wheel, with the switch being activated when the wheel encounters an obstacle. All of the monitoring switches are connected in a normally closed monitoring loop.
This is different than previous systems that use phone dialers that simply access cellular or satellite telephone networks for communicating a serial communications protocol that is proprietary to each specific telephone manufacturer and/or cellular telephone carrier. These systems typically require proprietary wireless connectivity or auxiliary communication ports for interfacing with the phones. Specific adapters or other dedicated hardware are therefore often required. These adaptations for current systems result in relatively high implementation and connectivity costs.

Alarm system for monitoring at rural locations


Disclosed is an automatic gain controller capable of reducing signal saturation or signal distortion caused by out-of-band signals of a filter extracting an object signal or delay of a control signal and capable of precisely measuring a signal level in a filter band. An AGC response control section compares a level of control voltage (“V2_I terminal” signal) outputted from a first AGC control section and inputted into a “V2_I terminal” with a level of control voltage (“V3_I terminal” signal) outputted from a second AGC control section and inputted into a “V3_I terminal”. If the control voltage, which is the “V3_I terminal” signal, outputted from the second AGC control section is less than the control voltage, which is a “V2_I terminal” signal, outputted from the first AGC control section, the AGC response control section controls an AGC amplifier by using the control voltage outputted from the second AGC control section. If the control voltage, which is the “V3_I terminal” signal, outputted from the second AGC control section is greater than the control voltage, which is the “V2_I terminal” signal, outputted from the first AGC control section, the AGC response control section controls the AGC amplifier by using the control voltage outputted from the first AGC control section.

1. Field of the Invention
The present invention relates to an automatic gain controller.
2. Description of the Related Art
In a conventional automatic gain controller having a filter in a control loop, an output signal of the conventional automatic gain controller is often interrupted due to a delay of response characteristics thereof caused by a signal delay from the filter. In order to solve the above problem, a method has been proposed, wherein if a signal level has a sudden variation, a control signal generator having a rapid time constant is utilized to create a control signal to cope with a delay of the control signal caused by the filter, and at the same time, control information is copied between the control signal generators in such a manner that an output signal of an automatic gain controller has no variation in level (referred to in Japanese Patent No. 3,240,458).
In addition, in the conventional automatic gain controller having the filter in the control loop, if a level control of an automatic gain control is carried out according to in-band signals of the filter, the automatic gain control may be carried out to match levels of the in-band signals of the filter. Accordingly, if out-of-band signals of the filter are greater than in-band signals of the filter, saturation caused by the out-of-band signals of the filter may occur in an amplifier installed at a front end of the filter. For this reason, a method has been proposed in which amplifiers are cascade-connected through a filter and an automatic gain control is separately carried out with respect to each amplifier installed at front and rear portions of the filter (referred to in Japanese Patent No. 3,086,060).
Although above-described Japanese Patent Publication No. 3,240,458 discloses a technique capable of solving a delay of response characteristics caused by a signal delay from a filter and properly generating an output signal of an automatic gain controller, when a level control of an automatic gain control is carried out according to in-band signals of the filter, saturation may occur in an amplifier installed at a front end of the filter caused by out-of-band signals of the filter, if out-of-band signals of the filter are greater than in-band signals of the filter.
In addition, although above-described Japanese Patent Publication No. 3,086,060 can adjust a signal level at a front end of a filter by tracking variations of levels of out-of-band signals of the filter, if an automatic gain control for the amplifier installed at the front end of the filter is carried out with a high-speed response according to variation of out-of-band signals of the filter, unnecessary variation may occur in the in-band object signals of the filter even though the object signals are not subject to variation.
That is, if the automatic gain control for the amplifier installed at the front end of the filter is carried out with the high-speed response according to the variations of the signals, the in-band object signals of the filter may be subject to unnecessary variation, so the automatic gain control for the amplifier installed at the rear end of the filter may be carried out according to the variations of the object signals with a high-speed response characteristic. However, if the automatic gain control with respect to the object signals is carried out with the high-speed response, signals may be modulated due to the automatic gain control and signal distortion may occur caused by an amplitude compression action of the automatic gain control.
Therefore, according to above-described Japanese Patent publication No. 3,086,060, the automatic gain control for the amplifier installed at the front end of the filter must be carried out with a low-speed response according to the variations of out-of-band signals of the filter. In such a case, noise is generated by the out-of-band signals of the filter due to low response characteristics of the automatic gain control. If the automatic gain control is carried out at a high-speed with respect to both amplifiers installed at front and rear ends of the filter, distortion of the object signals may occur when the automatic gain control is carried out with respect to the amplifier installed at the rear end of the filter, so communication quality will be lowered.


A sustained-release pharmaceutical preparation utilizing a pH controlled diffusion membrane composed of a pH sensitive film-forming polymer. The film forming polymer may be an enteric polymer containing phthalic acid with one carboxyl group attached to the enteric polymer via an ester bond, and the second carboxyl group remaining a free acid so that the modified film forming polymer is hydrophobic at low pH and hydrophilic at higher pH. Hydrophobic stearyl side chains are attached to the enteric polymer which causes the pH controlled diffusion membrane to remain insoluble at high pH. Alternatively, the pH sensitive film forming polymer may be a polymer containing hydrophobic and free acid groups so that the modified film forming polymer is hydrophobic at low pH and hydrophilic but insoluble at high pH. In the preferred sustained-release pharmaceutical preparation the film forming polymer is coated into core drug particles to produce a pH controlled diffusion membrane surrounding the core drug and form microparticles which may be admixed with free drug or time-release drug and placed in a gelatin capsule or tabletted.

The present invention relates to oral sustained release pharmaceutical preparations in the form of microparticles of core drug particles surrounded by a pH controlled diffusion membrane.
As is well known, the maximum time of effectiveness in many pharmaceutical preparations, particularly those containing a drug such as aspirin, acetaminophen, propranolol, and dextromethorphan, etc. is only a few hours because of biological modification and/or elimination of the medication in the body. Consequently repeated dosages must be taken at frequent intervals to obtain long term therapeutic levels of drug. Furthermore, these drugs usually dissolve readily in the digestive juices and the total dosage is immediately fed into the blood stream. After high initial peak concentrations, the level of drug in the blood stream constantly decreases because of the biological elimination, so there is little or no therapeutic effect at the end of the period between dosages. As a result, the therapeutic effect fluctuates between dosages corresponding to the peaks and valleys in the level of drug in the blood as commonly measured by trough to peak ratios.
One common approach in attempting to provide a more constant drug level is to microencapsulate aspirin, for example, with a capsule wall material which provides a slower dissolution rate than free aspirin. The early work in that regard is represented by U.S. Pat. Nos. 3,155,590; 3,341,416; 3,488,418, and 3,531,418. Those patents, among others, disclose dispersing particles of aspirin in hot cyclohexane solution containing ethyl cellulose and then introducing a phase-separation inducing agent, such as butyl rubber or polyethylene. Upon cooling, the aspirin particles become coated with ethyl cellulose. The coated particles are then admixed with tabletting excipients and formed into dosage-sized tablets. When ingested, the tablets disintegrate rapidly and the individual particles of encapsulated aspirin are dispersed in the stomach. The gastric juices slowly diffuse through the capsule walls, dissovle the aspirin, and the dissolved aspirin slowly diffuses or leaches out through the capsule walls into the body. Although the resultant blood level content is sustained to a measurable extent, the aspirin is diffused into the body rapidly enough so there is an initially high blood level content which decreases quite rapidly within a few hours. These dissolution properties yield undesirable blood aspirin concentration versus time curves.
Guy U.S. Pat. No. 4,025,613 discloses a multi-layered tablet. One layer comprises aspirin coated with cellulose acetate phthalate and the other layer is free aspirin. With multi-layered microencapsulated particles, as discussed above, the dissolution rate decreases rapidly and the blood aspirin concentration at 2-3 hours must greatly exceed the therapeutic level in order to maintain adequate aspirin concentrations at 8 hours. As a result, efforts have been made to adjust the rate of dissolution and thus, control the timing of sustained drug release. See for example, Peters U.S. Pat. No. 3,492,397 where the dissolution rate is said to be controlled by adjusting the wax/ethyl cellulose ratio of the applied spray coating. See also U.S. Pats. No. 4,205,060 and 3,488,418 where it is indicated that the rate of dissolution can be controlled by varying the thickness of the coating.
Another method for providing an encapsulated pharmaceutical composition is discussed in published European patent application No. 77,956, published May 4, 1983. EPO Publication No. 77,596 discloses the use of microcapsules containing a coated core material such as pharmaceutical compounds and foodstuffs. The coating is applied by dispersing the core material into a solution containing ethyl cellulose as the wall-forming material. A phase separation of the ethyl cellulose from the dispersion of core material is carried out by cooling the dispersion. During this cooling, an enteric polymer material is incorporated into the ethyl cellulose coating walls by adding the enteric polymer material with stirring while the ethyl cellulose is still in the "gel" state. The enteric polymer material thus added penetrates, and is dispersed into the coating walls. When the microcapsules are administered, the release of the active compound does not generally occur in the stomach. However, the enteric polymer material is easily dissolved in the intestinal tract, thereby making the microcapsules porous. The porosity of the microcapsules promotes the rapid release of the active compound in the intestinal tract.
A similar approach is found in Japanese Patent Publication No. 12614/81 published Mar. 23, 1981. Japanese Publication No. 12614/81 discloses an enteric protective coating composition which will not readily dissolve in acidic gastric juices, but rapidly (within minutes) dissolves at the pH found in the intestines. The enteric coating is an aqueous dispersion of, for example. hydroxy propyl methyl cellulose phthalate, a gelling agent such as diacetin, and hydroxy propyl methyl cellulose. See, also. Japanese Patent Publication No. 11687/81, published Mar. 16, 1981, which uses hydroxy propyl methyl cellulose phthalate as an enteric coating.
The systems described in the EPO Japanese Publications are essentially "delayed" release mechanisms. There is a delay of medicament release in the stomach, but once the coated medicament reaches the intestines, the release of medication is rapid. There is no sustained-release of medication in the intestines. Furthermore, these systems use a "mixed" wall material which result in processing difficulties.
Finally reference is made to applicants' copending, application Ser. No. 017,988, filed Feb. 24, 1987. the disclosure of which is hereby incorporated by reference. In the copending application there is disclosed a sustained-release pharmaceutical preparation comprising a dual walled coated drug having an inner wall microencapsular control coating, such as ethyl cellulose, and an outer wall enteric coating, such as ethyl cellulose, and an outer wall enteric coating, such as cellulose acetate phthalate. Such a dual-walled material will release less than 10% per hour of core drug while in the stomach but will slowly release the core drug in the intestines to provide adequate drug levels for 8 or more hours. While this represents an improved result, film forming polymers designed to have permeability controlled by pH will provide increased flexibility in designing drug release profiles and will make processing easier and more economical by eliminating the need for a dual wall structure.
Thus, there remains a need for a film forming polymer with a permeability controlled by pH which can be used to coat core drug particles and produce microparticles which provide a delayed and sustained-release of drug.

Sustained release pharmaceutical preparations having pH controlled membrane coatings


An embodiment of the present disclosure provides an array substrate, and the array substrate including: at least a data line and at least a gate line; and a plurality of pixel units defined by the data line and the gate line. Each of the plurality of pixel units includes a thin film transistor, a first electrode and a second electrode, and the first electrode and the second electrode overlap each other and are insulated from each other and the second electrode is positioned above the first electrode. An alignment film is formed on a surface of the array substrate, a direction of the second electrode and one side of the array substrate form a predetermined angle and a rubbing direction of the alignment film is parallel to the one side of the array substrate.

One or more embodiments of the present disclosure relate to an array substrate and a liquid crystal display (LCD).
In an advanced-super dimensional switching (AD-SDS) LCD, a parallel electric field generated through the fringes of pixel electrodes or common electrodes positioned in the same plane and a vertical electric field generated between the pixel electrode and the common electrode on different levers can constitute a multi-dimensional electric field, and thus, liquid crystal molecules that are orientated between the pixel electrodes or the common electrodes and directly above the pixel electrodes or the common electrodes inside a liquid crystal cell can be rotated, thereby the work efficiency of liquid crystal display of a plane orientation mode can be improved and a light-transmitting efficiency can be increased. The AD-SDS technology can improve the displaying quality of a TFT-LCD, and has advantages of high transmittance, wide viewing angle, high aperture ratio, low chromatic aberration, short response time, no push Mura, etc.
Advanced-Super Dimensional Switching-Liquid Crystal Displays (AD-SDS-LCDs) can be classified into dual-domain AD-SDS-LCDs and single-domain AD-SDS-LCDs based on the direction of pixel electrodes on an array substrate. Compared with a dual-domain AD-SDS-LCD, a single-domain AD-SDS-LCD has a relatively high transmittance and is broadly applied to a small-size product.
An existing array substrate of the single-domain AD-SDS-LCD on which a pattern is formed is shown in FIG. 1. As shown in FIG. 1, one side of the array substrate is used as a reference line, the data lines are parallel to the reference line, the gate lines are perpendicular to the reference line and the direction of the pixel electrodes are parallel to the data lines. With respect to the single-domain AD-SDS-LCD, rubbing directions (i.e., a original orientation of a liquid crystal) of the alignment films respectively formed on the array substrate and the color filter substrate of the LCD are required to form an angle of about 7 degree with the direction of the pixel electrodes in order to avoid the driving disorder, that is to say, the original orientation of the liquid crystal forms an angle of about 7 degree with the reference line. However, with reference to a viewing angle effect view shown in FIG. 2, it can be seen that the angle formed between the original orientation of the liquid crystal and the reference line may cause a preferable viewing angle region (a cross region in FIG. 2) to shift about 7 degree about the reference line, and thus, a displaying discomfort occurs.

Array substrate and liquid crystal display

BEIJING BOE OPTOELECTRONICS TECHNOLOGY CO., LTD.


A system and method for infusing a drug under continuous positive pressure (such as convection enhanced deliver) to a target tissue to be treated is particularly useful for post-resection anticancer drug therapy. The system comprises a drug infusion catheter having an expandable device which is expanded within the target tissue such that the target tissue conforms to an outer surface of the expandable device, thereby creating a form of seal around the target volume in order to maintain an effective drug pressure gradient within the target tissue. The system further comprises a sensor to measure a parameter which can be correlated to the degree of conformance between the target tissue and the outer surface of the expandable device. The sensor is coupled to a feedback control system to determine whether there is a loss of conformance, and to adjust the expansion of the expandable device in order to maintain good conformance.

Malignant tumors are often treated by surgical resection of the tumor to remove as much of the tumor as possible. Infiltration of the tumor cells into normal tissue surrounding the tumor, however, can limit the therapeutic value of surgical resection because the infiltration can be difficult or impossible to treat surgically. Direct chemo-drug (anticancer drug) delivery therapy and radiation therapy are the two common post-resection treatment methods used to supplement surgical resection by targeting the residual malignant cells after resection, with the goal of sterilizing them, reducing the rate of recurrence, and/or delaying the time to recurrence. Radiation therapy can be administered through one of several methods, or a combination of methods, including permanent or temporary brachytherapy implants, and external-beam radiation. Direct chemo-drug delivery therapy is typically administered by inserting a catheter device into the resected cavity and infusing chemo-drugs through a lumen in the catheter and into the resected cavity where the drugs diffuse into the surrounding tissue. In some cases, direct chemo-drug therapy is applied to a tumor without resection in order to shrink the tumor prior to resection, or in the case of where surgery is contraindicated (e.g. inoperable tumors).
However, in certain treatment areas of the body, it is very difficult for the drugs to penetrate the target tissue (either a tumor itself, or the tissue surrounding the area of a resected tumor). For example, it is difficult for large molecule drugs to penetrate the brain parenchyma when treating brain tissue. Thus, in these situations, the chemo-therapy does not treat a sufficient thickness of tissue (typically 1-2 cm) to target the residual malignant cells. In order to improve drug penetration in these types of situations, a method of directly delivering the drugs to the target tissue under positive pressure has been developed. This method is commonly referred to as convection-enhanced delivery (CED). CED uses continuous positive pressure drug infusion to generate a pressure gradient to cause the drug to diffuse into the desired thickness of target tissue.
However, current methods and devices have several drawbacks. For one, at some point during infusion, the drugs tend to leak out of the target volume (the volume of target tissue) through the space in the tissue created by the catheter. The drugs can then follow the catheter pathway through the tissue and out of the patient's body. Moreover, once this occurs, it is difficult to maintain the pressure gradient within the target volume resulting in ineffective drug penetration into the target tissue.
Accordingly, there remains a need for methods and devices which can provide for effective direct delivery of drugs under continuous positive pressure drug infusion.

Systems and methods for drug infusion with feedback control


A method and system are described for illuminating a document, such as passports, identity documents or other types of documents, using illumination means under control of a processor to effectively control the angle and direction of light on such documents to expose optically variable devices such as holograms, intaglio printing and optically variable coating and inks contained in or on the documents and the material laminating the documents.

Illegal modifications and counterfeiting of identification documents, such as passports, drivers licenses, and identification cards and badges; and documents of value, such as bonds, certificates and negotiable instruments, has been increasing year by year to the concern of companies, governments and their agencies that issue these documents. To counter this problem new materials have been and are being developed for the production of such identity documents and documents of value, that make it more and more difficult to alter or counterfeit the documents, and easier and faster to detect if such documents are counterfeit or have been altered.
These new materials utilize new laminating schemes and materials that utilize optically variable devices, invisible inks that only appear when illuminated by certain wavelengths of visible or invisible light; retro-reflective layers inside the laminating materials; different types of inks that have one color under normal ambient light but show up as different colors when illuminated by certain wavelengths of invisible light, and many other schemes. In addition, magnetic and radio frequency (RF) taggants may be added to the laminates or base material of documents during their manufacture, and such taggants may be detected while being invisible to the eye. Further, micro-miniature smart chips may be embedded in such documents, such as they are in smart cards, and used in reading and verifying documents such as listed above.
The rise of passports, documents of value, and other security and identification documents having anti-counterfeiting, anti-alteration and verification features, and the new laminating materials, some of which are briefly described above, have created a growing need for new and improved document reader, verifier equipment that can rapidly read, verify, and analyze many different types of passports, documents of value, identity and security documents made utilizing the new materials, techniques and laminating materials described above. Such document reader, verifier equipment is desperately needed at high traffic locations, such as international airports around the world, where millions of travelers pass between countries each year. However, such new and improved equipment is also needed for many other applications such as reading and checking identity badges of employees and others in high security installations where government or industrial confidential or secret information is to be protected, and access and movements are carefully limited, controlled and recorded. In addition, such new and improved reader verifier equipment is desperately needed to check different types of documents of value.
Document reader verifier equipment for identity documents and documents of value require document illumination and imaging systems to illuminate documents with light of different wavelengths and with the light being applied to documents at different angles in order to detect and/or verify security features and unauthorized alterations in such documents. As new types of security features are created and used in such identity documents and documents of value there is a need in the prior art for new and improved document reader verifier equipment and the illumination and imaging systems used therein.

Method and system for a processor controlled illumination system for reading and analyzing materials


A motor assembly for a vacuum cleaner for providing a user with a quieter environment during a cleaning work, and a vacuum cleaner having the same, is disclosed. The motor assembly includes a motor generating a suction force, an auxiliary filter member disposed on an airflow path connecting the motor to a dust-collecting apparatus for filtering a second time the air discharged from the dust-collecting apparatus, and a motor casing. The motor casing includes a first chamber connected to the dust-collecting apparatus with the auxiliary filter member mounted therein. A second chamber is connected to a discharge opening of the cleaner body and includes the motor mounted therein. A connection path is in fluid communication with the first chamber and the second chamber.

A general vacuum cleaner performs cleaning work by drawing in dirt together with ambient air from a cleaning surface while traveling along the cleaning surface. The vacuum cleaner includes a cleaner body and a suction assembly. FIG. 1 is a view showing an appearance of an upright type vacuum cleaner as an example of the above-described general vacuum cleaner, and FIG. 2 is a view showing the cleaner body of the vacuum cleaner of FIG. 1.
Referring to FIGS. 1 and 2, a conventional upright type vacuum cleaner 100 includes a suction assembly 110, a cleaner body 120, a dust-collecting apparatus 130, and a motor assembly 150. The suction assembly 110 has an opening for drawing in dirt (not shown) formed in a bottom thereof from a cleaning surface therethrough. The cleaner body 120 is pivotably connected to one side of the suction assembly 110, and has a discharge opening 127 formed in a rear portion to discharge the air therethrough as the air is drawn in through the dirt-suctioning opening and filtered by the dust-collecting apparatus 130. A front casing 121 and a rear casing 122 form the exterior contour of the cleaner body 120.
The dust-collecting apparatus 130 separates dirt from air that is drawn in through the suction assembly 110. As shown in FIGS. 1 and 2, the vacuum cleaner 100 employs a cyclone dust-collecting apparatus 130 which is mounted in a dust-collecting chamber 125 of the cleaner body 120. The dust-collecting apparatus separates dirt using a centrifugal force generated by swirling the air entering into the cyclone dust-collecting apparatus 130, and also includes an auxiliary filter assembly 140 for filtering a second time the air discharged from the cyclone dust-collecting apparatus 130. Meanwhile, an ascending/descending unit 160 ascends/descends a dirt-collecting receptacle 135 of the cyclone dust-collecting apparatus 130 in the dust-collecting chamber 125 to connect/disconnect the dirt-collecting receptacle 135 to/from a cyclone head portion 131 fixed to an upper end of the dust-collecting chamber 125 of the cleaner body 120.
The motor assembly 150 generates a suction force at the dirt-suctioning opening and is disposed in the cleaner body 120 and is in fluid communication with the dirt-suctioning opening. The motor assembly 150 includes a motor casing 153 for covering the exterior of a motor 305 (see FIG. 4) which generates the suction force. The motor casing 153 also guides the air discharged from the auxiliary filter assembly 140 to the discharge opening 127 of the cleaner body 120.
In a conventional vacuum cleaner 100 with the above construction, since the motor assembly 150 and the auxiliary filter assembly 140 are constructed independently from each other, an airflow path for connecting the motor assembly 150 and the auxiliary assembly 140 is additionally required. Further, a sealing device is also required to seal the airflow path. Also, in situations where the airflow path is provided to connect the motor assembly 150 and the auxiliary filter assembly 140, since noise occurs during operation in the connection portions of the airflow path and the motor assembly 150 and the auxiliary filter assembly 140, there is a problem that a user cannot enjoy a quiet cleaning work. Furthermore, due to the addition of the extra airflow path and the sealing device, a manufacturing process of the vacuum cleaner 100 becomes more complicated and a manufacturing cost is increases.
Thus, a heretofore unaddressed need exists in the industry to address the aforementioned deficiencies and inadequacies.

Motor assembly and vacuum cleaner having the same


This method for detecting and classifying a scratch on a semiconductor wafer, in accordance with the invention, first defines a coordinate system on the wafer. The method creates a list of failed cells according to coordinates corresponding to the cell failures on the wafer. The number of failed cells, in total, is determined. Through calculating the standard deviation of the failed cells at a plurality of different angles, based on the list of failed cells and the total number of failed cells, a determination is made as to whether the wafer has a potential scratch. Plotting the standard deviations versus the number of failed cells and comparing that point to other known points determines the presence of a scratch. The steps of detecting and classifying scratches occurring on wafers may be performed by a computer.

1. Technical Field
This disclosure relates to semiconductor wafers and more particularly, to a method of detecting and classifying scratches occurring during wafer processing and can also be applied to any image detection or recognition problem dealing with elongated patterns.
2. Description of the Related Art
Semiconductor wafers, such as those made of silicon, are used as a substrate for processing integrated circuits chips. Scratches routinely result from the manufacture process, for example, as the result of contact printing, a lithography process, where a mask comes in contact with the wafer for purposes of building circuits. To classify the wafers in the past, manual inspection by an engineer was necessary. Manual inspection is so time consuming that inspection of each wafer is economically impossible.
During wafer processing, defect inspection techniques and electrical tests identify certain fail signatures that indicate the presence of a scratch. The results of these inspection techniques can include, for example, detailed wafer maps or bit fail maps. In a manufacturing environment that processes thousands of wafers per week it is not practical to manually classify every wafer for reasons of time and efficiency.
Therefore a need exists for an efficient method of detecting and classifying scratches occurring during wafer processing in the semiconductor industry.
The method for detecting and classifying a scratch on a semiconductor wafer, in accordance with the invention, first defines a coordinate system on the wafer. The method creates a list of failed cells according to coordinates corresponding to the cell failures on the wafer. The number of failed cells, in total, is determined. Through calculating the standard deviation of the failed cells at a plurality of different angles, based on the list of failed cells and the total number of failed cells, a determination is made as to whether the wafer has a potential scratch. Plotting the standard deviations versus the number of failed cells and comparing that point to other known points determines the presence of a scratch. The steps of detecting and classifying scratches occurring on wafers may be performed by a computer.
In other methods, the step of defining a coordinate system on the wafer may include the steps of assigning chips on the wafer a number of cells in the x and y directions and defining the coordinate system based on the cells and a number of chips. The step of creating a list of failed cells, may include the steps of assigning failed cells a value, creating the list of failed cells based on the cells assigned the value, and creating the list of failed cells according to locations on the coordinate system. The step of determining a standard deviation of the failed cells at a plurality of different angles, may include the steps of calculating the standard deviation for the plurality of different angles from a given position, determining the ratio of a lowest standard deviation to a highest standard deviation of the calculated standard deviations, graphing the ratio of standard deviations versus the total number of failed cells, and comparing a graphed point to points stored in a database to determine if a scratch exists. The step of determining a standard deviation of the failed cells at a plurality of different angles, may include the steps of calculating the ratio of a lowest standard deviation to a highest standard deviation from a plot of standard deviations, and comparing the ratio of standard deviations and number of failed cells against a range of values to determine if a scratch exists on the wafer. The step of comparing a ratio of standard deviations to the number of failed cells to determine the presence of a scratch, may include plotting the ratio of a lowest standard deviation to a highest standard deviation versus the number of failed cells, determining a position in the plot for the ratio and the number of failed cells, and comparing the position to other known positions from prior tests of wafers to determine if a scratch exists.
The step of calculating the standard deviation for the plurality of different angles from a given position, may include the steps of rotating the list of failed cells by a user defined angle, transforming the list of failed cells through coordinate transformation, calculating the standard deviation at each angle relative to the given position, and creating a schedule of standard deviations at the different angles.
A method for detecting and classifying scratches occurring during semiconductor wafer processing may include the steps of defining a total number of cells of a predefined size in an x and y direction, for chips on a wafer, calculating a total number of cells on the wafer, and developing a normalized coordinate system that assigns values between zero and one for each x and y coordinate, assigning failed cells a value, creating a schedule of a location of failed cells in the coordinate system, defining a number of failed cells, having the assigned value from the schedule of failed cells, calculating a standard deviation at different angles to a given line by rotating the positions of the failed cells by a user defined angle, transforming a coordinate list through coordinate transformation, creating a schedule of standard deviations at the different angles, determining a lowest standard deviation and a highest standard deviation from the schedule, calculating a ratio of the lowest standard deviation to the highest standard deviation for the wafer from the schedule, and determining the presence of a scratch by comparing the ratio and the number of failed cells against a range of values which are likely to denote a scratch on the wafer.
In other methods, the step of developing a normalized coordinate system that assigns values between zero and one for each x and y coordinate, may include the step of developing a system of cells that assigns values between zero and one for each x and y coordinate by dividing the value in the x or y direction by the total number of cells in the same x or y plane of the cell. The step of assigning failed cells a value, creating a schedule of the location of failed cells in the coordinate system, may include the step of assigning the failed cells the value of 1. The step of calculating a standard deviation several times, at different angles to a fixed position by rotating the coordinate list of failed cells by a user defined angle, may include the steps of rotating through coordinate transformation and determining the standard deviation at the new angle from the given line. The step of creating a schedule of standard deviations at the different angles may include the steps of plotting the standard deviation versus the angle of transformation and identifying the lowest standard deviation and the highest standard deviation from a graph of standard deviation versus the angle of transformation. The step of determining the presence of a scratch by comparing the ratio and the number of failed cells against a range of values which are likely to denote a scratch may include the step of plotting the ratio versus number of failed cells and comparing the plot to a database of stored points corresponding to scratches on a set of pervious wafers.
A method detecting and classifying an elongated pattern on an image may include defining a coordinate system for a digitally rendered image creating a list of positions on a pixel map relating to an object on the coordinate system, defining a total number of pixels relating to the object, determining a standard deviation of the pixels relating to the object at a plurality of different angles based on the list of pixel positions and the total number of pixels relating to the object, and comparing a ratio of standard deviations to the number of pixels relating to the object to determine the presence of the elongated pattern.
In other methods the step of determining a standard deviation of the failed cells at a plurality of different angles, may include the steps of calculating the standard deviation for the plurality of different angles from a given position, determining the ratio of a lowest standard deviation to a highest standard deviation of the calculated standard deviations, graphing the ratio of standard deviations versus the total number of pixels relating to the object, and comparing a graphed point to points stored in a database to determine if the elongated pattern exists. The means for determining a standard deviation at a plurality of different angles based on the list of pixel positions and the total number of pixels relating to the object, may include the steps of rotating the list of pixels by a user defined angle, transforming the list of pixels through coordinate transformation, calculating the standard deviation at each angle relative to the given position, and creating a schedule of standard deviations at the different angles. The means for determining a standard deviation at a plurality of different angles based on the list of pixels positions and the total number of pixels relating to the object, may include the steps of calculating the ratio of a lowest standard deviation to a highest standard deviation from a plot of standard deviations, and comparing the ratio of standard deviations and number of pixels relating to the object, against a range of values to determine if the elongated pattern exists on the wafer. The method may include the steps of comparing the ratio of standard deviations to the number of pixels relating to the object to determine the presence of the pattern, may include, plotting the ratio of a lowest standard deviation to a highest standard deviation versus the number of pixels relating to the object, determining a position in the plot for the ratio and the number of pixels relating to the object, and comparing the position to other known positions from prior tests of images to determine if the elongated pattern exists.

Method for detecting and classifying scratches occurring during wafer semiconductor processing

Infineon Technologies North America Corp


An improved protected graphics assembly according to the invention comprises the following sequential layers: optionally, at least one adhesive layer; at least one graphics layer; and at least one outwardly exposed polymer layer that is essentially free of low surface energy materials and has a gloss value of greater than 90 when tested according to ASTM D2457-03 at a 60-degree angle. The assembly is beneficially applied to a variety of articles and used in a variety of related methods. In an exemplary embodiment, a race car comprises a protected graphics assembly that comprises: optionally, at least one adhesive layer; at least one outwardly exposed polymer layer that is essentially free of low surface energy materials; and at least one graphics layer substantially protected from exterior exposure by the polymer layer.

The present invention relates generally to improved protected graphics and methods related to the same, which graphics and related methods are particularly useful for application to vehicles according to an exemplary aspect of the invention.
Graphical images (also referred to simply as "graphics") take many forms and are used to provide desired textual or pictorial representations on a surface. A wide variety of materials are used to create graphical images on a surface, and graphics can generally be applied to a wide variety of surfaces. With that in mind, graphic designers face many challenges. A primary challenge is associated with successful application of a graphical image having a desired quality on a surface. Another challenge is associated with maintaining those applied graphics over time. As an example, materials used to create graphical images on a surface are prone to fading when exposed to radiation such as that in ultraviolet (UV) light. Mechanical (e.g., abrasive) or chemical contact with graphical images also tends to degrade such graphics over time. Quality of a graphical image is often balanced against a competing interest in permanence of that image.
In order to increase permanency of graphical images, ink used to create such images is often formulated with additives that improve mar resistance or other performance properties of the ink. Such additives include, for example, silicones and other low surface energy materials. A problem arising from the use of such relatively low surface energy additives, however, is the tendency of low surface energy additives to decrease the adherence of the inks to many substrates. Thus, while the ink itself may be improved with respect to its ability to resist degradation, the ink may not adequately adhere to the surface on which it is printed to form a graphical image, which can affect both the quality and the permanence of the image.
Another attempt to increase permanency of graphical images is application of the graphics under a film such that the graphics are outwardly visible, but yet protected, on a surface. Using this approach, graphics can be printed on a polymer film and adhered to a surface such that the graphical image lies between the polymer film and an underlying surface. The types of polymer films conventionally used in this approach are generally polyesters or fluoropolymers. Quality of the graphical image is often compromised, however, as the visual quality of the polymer film is generally not sufficient to allow undistorted viewing of the underlying graphics.
Further, conventional inks used to form such graphical images, which often have low surface energy additives as discussed above, often do not adequately adhere to adjacent polymer films or the low surface energy of an adjacent polymer film, such as a fluoropolymer film, can impair such adherence. Adherence is not only a factor as far as maintenance of graphics on a surface is concerned, but it is also a factor associated with ease of removability of such graphics when desired. For example, as team sponsorship or other insignia placed on a race car or other transportation vehicle changes, it is often desirable to easily remove outdated graphics from a vehicle's surface so that updated graphics can be applied in their place. When the graphics are part of an assembly containing multiple layers, interlayer delamination associated with inadequate adherence between layers can complicate the removal process.
A further consideration associated with protecting graphics with a polymer film overlay is weight associated with the polymer film. Particularly in the transportation industry, additional weight may lead to consumption of excess fuel and restrictions on the number of passengers or amount of cargo that an associated vehicle can safely and efficiently transport. Additional weight can also compromise operation of high performance vehicles, such as race cars. For example, as weight restrictions are often imposed on race cars, additional weight associated with surface paint or film decreases the amount of weight that can be strategically positioned elsewhere on the vehicle—such as in areas designed to increase the downforce (i.e., the downward pressure created by the aerodynamic characteristics of a car that allows it to travel faster through a corner by holding the car to the track or road surface) and, hence, performance of a race car. In particular, NASCAR's "Car of Tomorrow" is highly standardized, with more than two-hundred defined points that must be adhered to when designing a race car. Impacted by these new standards is aerodynamics of the race car. Making race cars wider and taller according to the new standards typically results in a corresponding sacrifice in aerodynamics, resulting in a slower average speed for the race car on a track. Thus, optimizing aerodynamic performance of a race car, which is impacted by the geometry and materials associated with a vehicle's surface, is highly desirable and of increasing concern.
Specific examples of some of the foregoing approaches to protecting graphics are now described. In setting forth the background of their teachings, U.S. Patent Publication No. 20070036929 (Boeing) describes how a conventional decal system (typically having a thickness of around 5 mils (125 microns)) consists of a clear polymer film provided to a printer, who prints graphics on the bottom side of the film, then applies pressure-sensitive adhesive.
According to the disclosure of this Boeing patent publication, thin film appliques are prepared for application to aircraft and, after their application, include a polymer film, a pattern layer, a pressure-sensitive adhesive, and an overlying clearcoat. Polymer films described therein are urethane, acrylic, epoxy, vinyl, or polyester and have a thickness of between 0.5 mil (13 microns) and 1.0 mil (25 microns). Pattern layers, which may embody graphics, are said to be formed from acceptable commercial-off-the-shelf inks, including pigmented acrylic ink, pigmented fast-dry acrylic ink, urethane ink with pigment, epoxy ink, and urethane enamel coating such as DESOTHANE brand coatings (available from PRC Desoto International, Inc. of Glendale, Calif.). The systems therein are described as being applicable to an aircraft skin, after which time edge sealer (e.g., a clearcoat) is applied around its borders. The clearcoat is substantial, having a thickness equalized toward a combined thickness of the remaining layers—i.e., the polymer film, the pattern layer, and the pressure-sensitive adhesive. The clearcoat is said to provide a smooth finish, a high gloss on the order of around 80-90 gloss units, and resistance to impacts and degrading fluids. However, the systems described in the Boeing patent publication are often not able to protect surfaces from damage arising from surface impact with stones and other debris, such as that hazardous debris often encountered by race cars during a race. Further, the need for a clearcoat in order to obtain desired gloss on the outer surface undesirably increases weight of the assembly.
PCT Patent Publication No. WO2007/048141 (entrotech composites, IIc; GLF Ref. No. entrotech 06-0002) describes how, when printed material is included on an exterior surface of a composite article, addition of a protective coating after application of the printed material on the surface is not required. Any printed material desired to be placed on an exterior surface of a composite article is pre-printed onto a protective sheet prior to its bonding to the underlying composite article. The protective sheet is then applied to the surface of an underlying composite article such that the printed material is outwardly visible. Protective sheets described therein have enhanced durability (e.g., abrasion resistance), impact resistance, and fracture toughness and are stated to be useful in a range of indoor and outdoor applications—for example, the transportation, architectural and sporting goods industries. However, as the protective sheets described therein are integrally bonded to the underlying surface, they are not easily removable from such surfaces or capable of being selectively applied to, for example, a race car's surface after manufacture and assembly of the car. Similar restrictions are associated with the graphic image fusion in-molded and extruded parts described in U.S. Pat. No. 7,166,249 (Abrams et al.).
U.S. Pat. No. 7,048,989 (3M Innovative Properties Co.) describes sheeting that may comprise a graphic. The graphic may be exposed on the viewing surface of the sheeting or disposed between a topcoat and the viewing surface of the sheeting. The topcoats are typically digitally printed by at least one method selected from laser printing, ink-jet printing, and thermal mass transfer printing. The topcoat is preferably reverse-imaged and then disposed such that the image is between the topcoat and a retroreflective core. It is stated that the retroreflective sheeting having the water-borne acrylic based topcoat may be used for a variety of uses such as traffic signs, license plates, pavement markings (e.g., raised pavement markings), personal safety, vehicle decoration and commercial graphics such as retroreflective advertising displays, bus wraps, etc.
U.S. Pat. No. 7,141,294 (3M Innovative Properties Co.) describes a decorative film using no appreciable amount, or no amount, of polyvinyl chloride. This decorative film comprises a substrate, an adhesive layer for sticking the decorative film to an adherend formed on one surface of the substrate, a printed layer provided with a printed decorative pattern or character information formed on the other surface of the substrate, and a top clear layer for protecting the printed layer. The substrate is formed from an ethylene-(meth)acrylic acid copolymer. The top clear layer used as an outer-most layer is preferably made of a material that is superior in weatherability and water resistance and has high transparency (e.g., colorless coating compositions such as fluororesins, thermosetting urethanes, and ultraviolet-curing compositions). The decorative film is described as having flexibility for adhering, ink adhesion, water resistance, and weatherability with good balance. It is also described as being suitable for various adherends, particularly for adhering to buildings or vehicles used outdoors, including curved surfaces such as the body of vehicles.
Despite the number of methods conventionally used for application and maintenance of graphics of the desired quality, improvements in that regard are desired. For example, it would be desirable to provide a film comprising protected graphics without requiring additional layers to protect the graphics or enhance gloss value of the underlying layers within the film. Particularly in the race car industry, such a film would facilitate obtainment of the ever-desired optimized aerodynamic performance.


The present invention relates to retransmissions in a communications system and more especially it relates to link load control in a cellular mobile radio system particularly in a Universal Mobile Telecommunications System, UMTS. BLER targets are set depending on load.

Retransmission of data to or from a mobile station, MS, or user equipment, UE, is previously known. If data is received in error, it is requested for retransmission. If errors are frequent, data is requested for retransmission frequently. When the relative amount of transmissions that are retransmissions of previously transmitted data increases the effective user data rate reduces, for a constant channel data rate.
Increasing transmission power can often reduce transmission errors. Consequently, increasing transmission power can reduce the relative amount of retransmissions. Correspondingly, transmission power can be reduced if the relative amount of transmission errors is sufficiently small.
U.S. Pat. No. 5,461,639 describes forward link power control in a CDMA system where error statistics are collected. The error rate is compared to a threshold. If the error rate exceeds the threshold, transmission power is increased. A code selector determines at which redundancy level to transmit. For each level of redundancy, the selector maintains a predetermined target error rate.
International Patent Application WO0013362 describes a method and device for adapting a transmission data rate or a transmitter power to the transmission quality of a transmission channel.
A channel data rate that gives an acceptable error rate at a given signal to noise ratio is selected. Transmission power is controlled.
It is also known to use medium access control and radio link control layers of a UMTS protocol structure in acknowledged mode for dedicated channels and to broadcast system information.
3rd Generation Partnership Project (3GPP): Technical Specification Group Radio Access Network, Physical Layer Procedures, 3G TS 25.331 v3.5.0, France, December 2000, specifies an RRC protocol. Section 8.1.1 describes broadcast of system information.
3rd Generation Partnership Project (3GPP): Technical Specification Group Radio Access Network, Physical Layer Procedures, 3G TS 25.322 v3.5.0, France, December 2000, specifies the RLC protocol. The RLC layer provides acknowledged data transfer service.
3rd Generation Partnership Project (3GPP): Technical Specification Group Radio Access Network, Physical Layer Procedures, 3G TS 25.301 v3.6.0, France, September 2000, specifies in chapter 5 Radio Interface Protocol Architecture of a UMTS system.
None of the cited documents describes a method and system of link control where error targets are selected as a function of transmission load in an ARQ scheme of a radio communications system.


A method for fairly allocating a differentiated bandwidth based on shared multicast traffic in transmission of downstream traffic in a Time Division Multiplexed-Passive Optical Network (TDM-PON) is provided. The method includes the steps of: deciding a total number of multicast groups to which services are currently provided, and a number of multicast groups to which a predetermined optical network unit (ONU) subscribes; calculating a multicast share degree in each of the multicast groups, and a total multicast share degree of the predetermined ONU in all of the multicast groups; dividing the total multicast share degree of the predetermined ONU by the total number of multicast groups to calculate a final normalized multicast share degree of the predetermined ONU; calculating an average multicast bandwidth of the predetermined ONU depending on a total bandwidth allocated to multicast traffic services on the basis of the final normalized multicast share degree; calculating the differentiated bandwidth of the predetermined ONU using ONU-specific service weights; and subtracting the average multicast bandwidth from the differentiated bandwidth of the predetermined ONU to calculate a maximum dynamic timeslot bandwidth of the predetermined ONU.

1. Field of the Invention
The present invention relates to a time division MULTIPLEXED passive optical network, and more particularly, to a method and system for fairly allocating a differentiated bandwidth based on shared multicast traffic in the transmission of downstream traffic from an optical line terminal (OLT) to an optical network unit (ONU).
2. Description of the Related Art
Due to ongoing growth of video-based applications requiring real-time data transmission and provision of integrated communication and broadcasting service, the total amount of Internet traffic has been rapidly increasing. In order to efficiently cope with this traffic increase, network providers apply Wavelength Division Multiplexing (WDM) technology to inter-city backbone networks and metro networks, thereby continuously increasing their transmission bandwidths.
In contrast, subscriber networks, in which the traffic transmitted from the backbone networks is distributed to end subscribers, have used conventional transmission technology based on Very-high-data-rate Digital Subscriber Line (VDSL) and cable modem together with high-speed Ethernet based technology. These subscriber network technologies can be deployed only in short distance area, and narrow transmission bandwidth is a basic bottleneck to provide the integrated services that are intensively discussed at present. In order to solve this problem, optical subscriber network technologies are being actively developed. The optical subscriber network technologies are directed to efficiently providing end subscribers with the transmission bandwidths required for the integrated services.
These optical subscriber network technologies include Time Division Multiplexed-Passive Optical Network (TDM-PON) technology and Wavelength Division Multiplexed-Passive Optical Network (WDM-PON) technology. The TDM-PON has a point-to-multipoint structure in which an optical line terminal (OLT) is connected with a plurality of optical network units (ONUs) through a passive optical splitter (POS), and a single transmission wavelength is shared with the plurality of ONUs in an optical layer. In the TDM-PON, downstream data transmission is carried out by TDM, while upstream data transmission is carried out by Time Division Multiple Access (TDMA) based on bandwidth reservation.
Unlike the TDM-PON, the WDM-PON has a logical point-to-point structure in which an individual transmission wavelength is allocated to each ONU. Data transmission between the OLT and the ONUs is independently performed without a time division process. Accordingly, the WDM-PON can provide subscribers with wider transmission bandwidths.
However, the deployment cost of WDM-PON is still high due to an expensive transmission system and optical devices, and thus it is predicted to take some time before it can be put to practical use. In contrast, the TDM-PON can make efficient use of the same wavelength through time division, and furthermore requires relatively inexpensive equipment. Thus, the TDM-PON has drawn attention as next-generation optical subscriber network technology.
According to a framing and multiplexing method of the data link layer, TDM-PON technology can be divided into E-PON, G-PON, and B-PON technology, all of which have the same basic up/downstream transmission control concept. First, in the case of upstream transmission, because the data transmission from a plurality of ONUs and Optical Network Terminals (ONTs) to an OLT, a common destination, is performed through a shared link, a proper Multiple Access Control (MAC) technique is required in order to prevent data collision. To this end, the ONUs and ONTs generally reserve the bandwidth of transmission window required for the next transmission period on the basis of the total amount of data stored in buffers, and the OLT arbitrates this reservation and then allocates a transmission timeslot, i.e., an upstream bandwidth. Hence, it is possible to maintain high network efficiency, and fairly allocate bandwidth to the ONUs as well. At this time, due to point-to-point communication in which the primary destination of a data frame transmitted from each ONU for a timeslot period of time is the OLT, which means no multicast traffic exist in TDM-PON area, it is possible to easily maintain fairness of the bandwidth allocation by controlling the timeslot size.
Unlike upstream transmission, downstream transmission is performed as follows. All data frames transmitted from the OLT are split in the optical layer through the POS and then broadcasted to all of the ONUs and ONTs. Each ONU filters the broadcast frames to receive only necessary frames on the basis of a destination address in a MAC layer. At this time, if all traffic is unicast traffic, i.e., frames directed to only a single destination, similar to upstream transmission, the OLT can allocate downstream transmission bandwidth to ONUs fairly by controlling timeslot size of ONU.
However, in practice, in the case of downstream transmission in the TDM-PON, there is always a large amount of multicast traffic due to multicast Video On Demand (VOD) and broadcasting video service, and this multicast traffic is simultaneously shared with the numerous ONUs through OPS. As such, in the case of downstream transmission, when the transmission timeslots are merely allocated in a uniform way, it is impossible to guarantee fair allocation of bandwidth.

Method and system for fairly allocating differentiated bandwidth based on shared multicast traffic in time division multiplexed passive optical network

Research and Industrial Cooperation Group