When refresh of a memory bank having a plurality of array banks is instructed, a refresh control circuit carries out the refresh by saving a row address latched in a row address latch circuit and a bank activation signal supplied to a bank drive unit respectively in a row address saving circuit and a bank activating information saving circuit. After the refresh completes, each array bank is returned to its original state before the refresh instruction is supplied, according to the saved row address and bank activate information. Accordingly, a synchronous semiconductor memory device in which the penalty at the time of the refresh is reduced is provided.

1. Field of the Invention
The present invention relates to a semiconductor memory device, and particularly to a semiconductor memory device having a plurality of memory cells which need refreshing of storage data within a prescribed time. The invention more particularly relates to a structure for refreshing in a multi-bank semiconductor memory device which has a plurality of memory banks and needs the refresh operation.
2. Description of the Background Art
In order to implement high-speed data transfer between a processing device such as a CPU (Central Processing Unit) and a DRAM (Dynamic Random Access Memory) as a main memory, a synchronous semiconductor memory device is used which inputs/outputs data in synchronization with a clock signal which is, for example, a system clock.
FIG. 16 shows states of external signals for a synchronous DRAM (SDRAM) which is one of conventional synchronous semiconductor memory devices. Referring to FIG. 16, in the SDRAM, an operation mode is determined by the combination of the states of respective external control signals /CS, /RAS, /CAS and /WE at the rising edge of an external clock signal CLK. In clock cycle #1, when chip selection signal /CS and row address strobe signal /RAS are set at L level, and the column address strobe signal /CAS and write enable signal /WE are set at H level at the rising edge of clock signal CLK, an active command is supplied and an operation for activating a memory cell array, that is, the row selecting operation, is carried out in the SDRAM. The row selection is carried out using an address signal ADD which is supplied simultaneously with the active command as a row address signal.
In clock cycle #3, when chip selection signal /CS and the column address strobe signal /CAS are set at L level and row address strobe signal /RAS and write enable signal /WE are set at H level at the rising edge of clock signal CLK, a read command of instructing reading of data is supplied. When the read command is supplied, an operation of selecting a memory cell column is carried out using address signal ADD which is applied currently as a column address signal, and data in a selected memory cell is read out. Since the SDRAM has a period referred to as CAS latency, read data Q attains a defined state after the period of the CAS latency. In the case shown in FIG. 16, the CAS latency is 1, so that read data Q attains a defined state at the rising edge of clock signal CLK in clock cycle #4. In the SDRAM, the read command is supplied to read out data of the number referred to as a burst length consecutively in each clock cycle using an address which is supplied simultaneously with the read command as a leading address. FIG. 16 shows a case in which data is read out with the burst length being 1.
In clock cycle #5, when chip selection signal /CS, column address strobe signal /CAS and write enable signal /WE are set at L level and row address strobe signal /RAS is set at H level, a write command of instructing writing of data is supplied. When the write command is supplied, a memory cell is selected using address signal ADD supplied currently as a column address, and data is written into a selected memory cell. When data is to be written, write data D is externally supplied simultaneously with the write command and taken into the SDRAM. Write data D which is taken therein is internally written into the selected memory cell at a prescribed timing. At the time of the data writing, data of the number of the burst length can also be written consecutively.
In the SDRAM, when the active command is supplied, the array attains an active state. In order to set the active array into a non-selected state, that is, a precharge state, chip selection signal /CS, row address strobe signal /RAS and write enable signal /WE are set at L level and the column address strobe signal /CAS is set at H level, and a precharge command is supplied in clock cycle #7. When the precharge command is given, the memory array which has been set in a selected state by the active command returns to the precharge state, and an internal selected row returns to the non-selected state.
In the SDRAM, a memory cell includes a capacitor which stores information therein as in a normal DRAM. Since the information stored in the capacitor needs to be refreshed within a prescribed period, chip selection signal /CS, row address strobe signal /RAS and write enable signal /WE are set at L level and column address strobe signal /CAS is set at H level in clock cycle #9. Accordingly, an auto-refresh command is supplied to automatically refresh a memory array. When the auto-refresh command is supplied, a refresh address which designates a memory cell to be refreshed is internally generated, data in the memory cell is refreshed according to the refresh address, and the memory array returns to the precharge state after the refresh completes.
As shown in FIG. 16, control signals are externally supplied synchronously with clock signal CLK, so that the internal operation starting timing can be determined using the rising edge of clock signal CLK as trigger. As a result, there is no need to consider a margin for internal operation timing which is necessary because of the skew or the like in the external control signals, and high-speed internal operation is implemented.
FIG. 17 schematically shows an internal configuration of a conventional SDRAM. Referring to FIG. 17, the SDRAM SD includes a plurality of memory banks BK0-BKn, and a data input/output buffer DB which is coupled commonly to memory banks BK0-BKn and inputs/outputs data. Each of memory banks BK0-BKn can be driven into active/inactive state regardless of the active/inactive state of other memory banks. For example, when memory bank BK0 is in the active state and a memory cell row is in the selected state, memory bank BK1 may be driven into the active state to drive a memory cell row into the selected state, and the memory cell row in the selected state may be driven into the non-selected state or the precharge state (inactive state).
The read command and the write command are supplied together with a bank address which designates a memory bank. Data can be input/output via data input/output buffer DB to/from the memory bank designated by the bank address. Therefore, at the time of access to one memory bank, other memory banks can be activated/inactivated to be sequentially accessed. Even at the time of page switching (to select a different word line), the memory array does not need to be set in the precharge state, so that data can be externally accessed consecutively. In particular, when data in a prescribed small area on a display screen is to be accessed in image processing, if memory banks BK0-BKn are configured to store pixel data on different scanning lines on the screen, data in the small area can be accessed at high-speed. In addition, when memory banks BK0-BKn are simultaneously set in the selected state, memory banks BK0-BKn can be utilized as the secondary cache, resulting in reduction of the penalty at the time of the cache miss.
FIG. 18 shows an entire configuration of the semiconductor memory device shown in FIG. 17 in detail. FIG. 18 presents a configuration having four banks as one example.
With reference to FIG. 18, the semiconductor memory device includes array banks 1a, 1b, 1c and 1d that can be driven into the active/inactive state independently of each other. The active state here represents a state in which a word line is selected in an array and a sense amplifier latches memory cell data, and the inactive state represents a state in which all word lines are in the non-selected state, the sense amplifier is in the inactive state, and each bit line of a bit line pair is precharged at a prescribed voltage level. Each of the array banks 1a-1d has the same configuration, and FIG. 18 shows the configuration of array bank 1a. Array bank 1a includes a memory array 1aa having a plurality of memory cells MCs arranged in rows and columns, and a row-related peripheral circuit 1ab which carries out an operation related to row selection in memory array 1aa. A word line WL is arranged corresponding to each row of memory cells MC, and a bit line pair BLP is arranged corresponding to each column of memory cells MC. FIG. 18 representatively shows one word line WL, one bit line pair BLP, and a memory cell MC placed at the crossing of them.
Row-related peripheral circuit 1ab includes a sense amplifier circuit provided to each bit line pair BLP, for differentially amplifying the potential of a corresponding bit line pair when activated, a bit line precharge circuit which precharges each bit line pair BLP to a prescribed potential level and others.
Bank drive circuits 2a, 2b, 2c and 2d for activating/inactivating corresponding array banks, as well as row address latches 3a, 3b, 3c and 3d are provided respectively to array banks 1a-1d. Each of bank drive circuits 2a-2d has the same configuration, and FIG. 18 shows a configuration of bank drive circuit 2a. Bank drive circuit 2a includes a row-related control circuit 2aa which controls an operation of row-related peripheral circuit 1ab of the corresponding array bank 1a according to a bank activation signal ACT0 from a bank activation control circuit 4, and a row selection circuit 2ab which decodes a row address signal RA0 supplied from a corresponding row address latch 3a and drives an addressed word line in corresponding memory array 1aa into the selected state according to the result of the decoding under the control by row-related control circuit 2aa. Row selection circuit 2ab includes a row decoder, and a word line drive circuit which drives an addressed word line into the selected state according to an output signal from the row decoder.
Row address latches 3a-3d each having a configuration described later in detail take in an address signal supplied according to a bank designation signal from bank activation control circuit 4, and latch and output the address signal. Operations of bank drive circuits 2a-2d and row address latches 3a-3d are controlled independently of each other under the control by bank activation control circuit 4.
Bank activation control circuit 4 receives an operation mode instruction signal from a command decoder 5 and a bank address signal BAi from an address buffer 6, and generates a control signal according to the operation mode instruction supplied from command decoder 5 for only a bank designated by bank address signal BAi. FIG. 18 exemplarily shows a configuration in which bank activation signals ACT0, ACT1, ACT2 and ACT3 are supplied from bank activation control circuit 4 to bank drive circuits 2a, 2b, 2c and 2d respectively. Bank activation control circuit 4 controls activation/inactivation of the bank activation signal according to an array activating instruction signal .phi.a and a precharge instruction signal .phi.p from command decoder 5 and bank address signal BAi from address buffer 6.
Command decoder 5 decodes signals supplied from a control signal input buffer 7 which in turn takes at the rising edge of clock signal CLK the signals /CS, /RAS, /CAS and /WE externally applied in synchronization with clock signal CLK, and generates the operation mode instruction signal according to the states of these signals. In some cases, command decoder 5 additionally uses a specific address signal bit supplied from address buffer 6 (the path is not shown) in order to generate the operation mode instruction signal. (This process is described later.)
Address buffer 6 takes externally supplied address signal AD and a bank address signal BA synchronously with the rising edge of clock signal CLK, and generates an internal address signal ADi and an internal bank address signal BAi.
The semiconductor memory device further includes a refresh control circuit 8 which generates a control signal necessary for the refresh according to a refresh mode instruction signal .phi.r from command decoder 5 to execute the refresh operation, a refresh counter 19 which generates a refresh address designating a memory cell to be selected and refreshed under control by refresh control circuit 8, and a multiplexer 10 which selects either internal address signal ADi from address buffer 6 or the refresh address from refresh counter 9 and supplies the selected one to row address latches 3a-3d under the control by refresh control circuit 8.
Refresh control circuit 8 supplies bank activation control circuit 4 with a control signal necessary for the refresh operation when refresh instruction signal .phi.r is supplied from command decoder 5. In the refresh mode, all memory array banks 1a--1a carry out the refresh operation via bank activation control circuit 4. Now, with reference to the timing chart shown in FIG. 19, an operation at the time of the refresh of the semiconductor memory device shown in FIG. 18 is described.
In clock cycle #0, row address strobe signal /RAS and chip selection signal /CS are set at L level and column address strobe signal /CAS and write enable signal /WE are set at H level, and an active command is supplied. When command decoder 5 receives the active command, command decoder 5 generates array activating instruction signal .phi.a and supplies it to bank activation control circuit 4. When bank activation control circuit 4 receives array activating instruction signal .phi.a, bank activation control circuit 4 supplies a latch instruction signal to a row address latch corresponding to a designated array bank according to bank address signal BAi supplied from address buffer 6, and drives array activation signal ACT for a corresponding bank drive circuit into the active state.
Multiplexer 10 has selected internal address signal ADi supplied from address buffer 6, and a row address latch provided corresponding to an array bank designated by the bank address takes the internal address signal supplied via multiplexer 10 and generates an internal row address signal RA. Accordingly, a bank drive circuit corresponding to an addressed bank is activated, and the row selecting operation is carried out in the designated bank.
Since the bank in the active state should be driven into the inactive state for the refresh operation, signals /CS, /RAS and /WE are set at L level and column address strobe signal /CAS is set at H level in clock cycle #3, and a precharge command is supplied. When the precharge command is supplied, command decoder 5 generates precharge instruction signal .phi.d and supplies it to bank activation control circuit 4. For the precharge command, two kinds of precharge commands are supported. One is a single precharge command for returning only one bank to the precharge state, and the other is an all-bank precharge command for returning all banks to the precharge state simultaneously. The single precharge command and all-bank precharge command are set respectively by the H level and L level of a specific bit (bit A10 for example) of address signal AD. The precharge command causes the bank activation signal ACT for a bank in the active state to be driven into L level of the inactive state, and array banks 1a-1d return to the precharge state under the control by bank drive circuits 2a-2d respectively.
After an elapse of the clock cycles necessary for the precharge operation, chip selection signal /CS, row address strobe signal /RAS and the column address strobe signal /CAS are set at L level, and write enable signal /WE is set at H level in clock cycle #6. Command decoder 5 determines that a refresh command is supplied, according to the states of signals supplied from control signal input buffer 7, and generates refresh instruction signal .phi.r for application to refresh control circuit 8. Refresh control circuit 8 starts refresh counter 9 according to refresh instruction signal .phi.r and causes refresh counter 9 to generate a refresh address, and causes multiplexer 10 to select the refresh address from refresh counter 9.
Bank activation control circuit 4 drives array activation signals ACT0-ACT3 into the active state to activate all banks under the control signal from refresh control circuit 7. Accordingly, the refresh address from refresh counter 9 is latched in row address latches 3a-3d, bank drive circuits 2a-2d all operate, and memory cells of a row designated by the refresh address are refreshed in each of array banks 1a-1d. At the time of the refresh operation, array activation signals ACT0-ACT3 are driven into the active state only for a prescribed period. After an elapse of the prescribed period, array activation signals ACT0-ACT3 return to the inactive state. In clock cycle #9 in FIG. 19, array activation signals ACT0-ACT3 are driven into the inactive state. Accordingly, all banks can be refreshed, and storage data can be refreshed periodically.
FIG. 20 schematically shows a configuration of a processing system using the SDRAM. With reference to FIG. 20, SDRAM SD is connected to a memory controller MCT via a memory bus 11. Memory controller MCT is connected to a processor PU via a system bus 13. Memory controller MCT is also connected to a bank management memory BMM. Memory controller MCT causes processor PU to wait and sets processor PU in a waiting state via system bus 13 at an interval of a prescribed time. In this state, memory controller MCT issues a refresh instruction to SDRAM SD. In the normal access mode, memory controller MCT stores information on whether a bank is active or inactive as well as a bank row address indicating a selected row address of a bank in the active state in bank management memory BMM for each of the banks, and constantly manages the states of the respective banks in SDRAM SD.
After memory controller MCT carries out the refresh for SDRAM SD via memory bus 11, memory controller MCT returns SDRAM SD to a state before the refresh, referring to bank management memory BMM. In other words, memory controller MCT supplies an active command for a bank in the active state together with its row address. After the state of SDRAM SD is recovered, memory controller MCT allows processor PU to make an access. Therefore, processor PU cannot access SDRAM SD not only during the period in which the refresh is carried out for SDRAM SD, but also during the period from completion of the refresh to the time when SDRAM SD is returned to its original state, and the penalty due to the refresh increases.
In order to return SDRAM SD back to its original state after the refresh is completed, clock cycles equivalent in number to banks that are in the active state when the refresh instruction is supplied are necessary. It is because the active command is supplied together with only one bank address at a time, that is, the active command is supplied only to one bank at a time. Consequently, if the storage capacity of SDRAM SD as well as the number of its array banks increase, the number of clock cycles in which processor PU is caused to be in the waiting state at the time of the refresh increases, and the penalty for the refresh increases. In other words, when the refresh is carried out, processor PU cannot access SDRAM SD and is caused to be in the waiting state. As a result, an advantage of the bank configuration of SDRAM SD that sequentially activation of the banks allows accessing with no influence of a precharge time at the time of page switching of a bank is lost.
In addition, memory controller MCT stores information concerning states of respective banks in SDRAM SD in bank management memory BMM. If the number of banks in SDRAM SD increases, the capacity of bank management memory BMM also increases, so that a load for managing the state of each bank by memory controller MCT also increases.
An SDRAM having no bank also requires, after the refresh, a memory to be returned back to a state before the refresh under the control by an external memory controller. As a result, the SDRAM having no bank also has a problem of an increased load of the external memory controller after the refresh is completed.

Multi-bank synchronous semiconductor memory device with easy control


A circuit and method of protecting the antiparallel diodes of a power bridge circuit from stress induced failures caused by the fast operation of the power switches. An auxiliary power switch is provided in parallel to the main power switch which is operable during the reverse recovery of the antiparallel diode, after which the main power switch carries the bulk of the switch current.

The present invention generally relates to electrical switch circuits, and in particular to methods and circuits for increasing the turn-on time in switches having a MOS controlled thyristor (MCT) through the innovative use of a thyristor based device.
A thyristor is a four layer semiconductor switching device. The bistable action of a thyristor depends on PNPN regenerative feedback. A thyristor can be unidirectional or bidirectional. A thyristor can be triggered to conduction from a desired point within a quadrant of an applied AC voltage. A triac and silicon bilateral switch are common bidirectional thyristors. The silicon controlled rectifier (SCR) is the most common unidirectional thyristor; others include the gate-turn off switch (GTO) and light activated silicon controlled rectifier (LASCR).
A MOS controlled thyristor is a power semiconductor device that combines a MOS transistor as the gate and a thyristor as the power source. This composite device has the lowest forward voltage drop of any voltage-controlled power source, including power MOS field effect transistors (MOSFET) and insulated gate bipolar transistors (IGBT). MCT's are turned on quickly over their entire active area and have a very large di/dt capability. A description of such devices and explanation of their fabrication process may be found in U.S. Pat. No. 5,111,268 to V. A. K. Temple, which is hereby incorporated by reference. For example, a 600 volt, 75 amp MCT has a di/dt of up to 10,000 amps/microsecond and may be turned on in about 0.2 microseconds. MCT's are used in integrated circuit applications to handle high currents and high voltages. Such applications include high frequency switching regulated power supplies, motor drives and. solid state switches for power electronics building block (PEBB) modules of different configurations for general circuit application.
The most common switch configuration is the half bridge consisting of two switching devices in series, each switching device having an antiparallel diode. Although theoretically, it is desired that the power switch have infinite turn-on speed, the faster such power switch turns on, the faster the antiparallel diode of the series connected switch is turned off. The finite stored charge and the low innate capacitance of power diodes leads to large diode reverse recovery currents and voltage overshoots that often cause failure of the diode. This invention provides a means to effectively provide the appropriate slowing in the turn-on time of a power switch to save the antiparallel diode of the power switch in series therewith. Moreover, this slowing is accomplished by increasing the turn-on time of the power switch without requiring that such means be active in the main part of the power switch cycle.
In applications, particularly half bridges using MCT's as the two main series connected switches, the extremely fast and efficient turn-on of the MCT may stress the antiparallel diode of the series connected MCT beyond the normal capability of such diode and thus induce diode failure by the voltage snap during reverse recovery.
One solution to the diode failure problem is to increase module inductance to limit the rate of change of current di/dt in the power switch. However, this leads to much increased losses and overvoltage stress at turn-off.
Another possible solution, albeit one with some difficulty, can be achieved by making the inductance saturable so that it is high at turn-on and low at turn-off. However, such saturable reactors need careful design and add losses, weight, volume, and cost. They are also limited in temperature capability.
Another possible solution involves a semiconductor based solution which includes paralleling the series connected MCT's with either IGBT's or MOSFET's. The IGET or MOSFET would be turned on before the MCT and used to control the di/dt of the MCT. Unfortunately, this solution requires considerable additional semiconductor area and losses as IGBTs and MOSFETs are far less turn-on and conduction efficient than the MCT.
It is, accordingly, an object of the present invention to provide a novel method and circuit using a thyristor based device to protect a power electronics circuit from failure due to diode stress.
It is another object of the present invention to provide a novel method and circuit to reduce the stress on an antiparallel switch diode during switch turn-on.
It is yet another object of the present invention to provide a novel method and circuit to increase the turn-on time, not the turn-off time, and reducing the di/dt capability of a power electronics switch while retaining the circuit's performance when the switch is fully turned on.
It is still another object of the present invention to provide a novel method and circuit for protecting a power electronics circuits.
It is a further object of the present invention to provide a novel method and circuit for controlling MOS controlled thyristor switches.
It is yet a further object of the present invention to provide a novel MCT power electronics switch having a slower turn-on time and current rate.
It is still a further object of the present invention to provide a novel semiconductor switch having an MCT connected in parallel with a smaller MCT and an inductor, and integrated in a single semiconductor device.

Protection device for solid state switched power electronics


Integrated circuit (IC) packages are described. Each IC package includes a die having an exposed metallic layer deposited on its back surface. Solder joints are arranged to physically and electrically connect I/O pads on the active surface of the die with associated leads. A molding material encapsulates portions of the die, leadframe and solder joint connections while leaving the metallic layer exposed and uncovered by molding material.

There are a number of conventional processes for packaging integrated circuit (IC) dice. By way of example, many IC packages utilize a metallic lead frame that has been stamped or etched from a metal sheet to provide electrical interconnects to external devices. The die may be electrically connected to the lead frame by means of bonding wires, solder bumps that have been preformed on the active surface of the die, or other suitable electrical connections. In general, the die and portions of the lead frame are encapsulated with a molding material to protect the delicate electrical components on the active side of the die while leaving selected portions of the lead frame exposed to facilitate electrical connection to external devices.
In some applications, it is desirable to leave the back surface (opposite the active surface) of the die exposed; that is, not to encapsulate the back surface of the die with molding material. By way of example, it may be desirable to leave the back surface of the die exposed in order to increase heat dissipation out of the die. This is especially relevant for packages used in power applications. Increasing heat dissipation out of an IC die generally results in greater device performance and stability.
While existing arrangements and methods for packaging IC devices work well, there are continuing efforts to improve the thermal performance of IC devices.


A drainage catheter system including a catheter, a collection bag, and a collection bag saddle, is provided. The catheter includes a catheter body having an interior lumen, an elongate tubular sheath operatively associated with the catheter body, and a layer of lubricant disposed between the catheter body and the tubular sheath. The sheath is inflatable after deployment to provide sealing engagement with an inner wall of the urethra. One end of the catheter body is adapted to be connected to the collection bag which includes a fluid entry portion having a one-way fluid valve, a gas separation chamber, and a one-way gas valve. The collection bag also includes a main liquid reservoir in fluid communication with the fluid entry portion and a sealed drainage member for permitting drainage of the main liquid reservoir. The collection bag saddle facilitates attachment of the collection bag to a patient's body, and includes a main body portion, a plurality of mounting pads attached thereto including adhesive backings, and collection bag mounting structure formed in the main body portion.

1. Field of the Invention
The subject invention is directed to catheters, and more particularly, to a urinary drainage catheter having a lubricated sheath associated therewith to reduce irritation to the urethra during insertion and removal of the catheter, and while the catheter is positioned therein in a functioning mode.
2. Description of the Related Art
Urethral catheters that are placed within a patient's lower urinary tract are well known in the art. One type of urethral catheter is a retention catheter. Retention catheters are supported in the patient's bladder to continuously remove urine therefrom. One type of urinary retention catheter is known in the art as a Foley catheter. It consists of an elongated tube through which extends a main drain lumen. The catheter is placed through the patient's urethra so that the distal end thereof extends into the patient's bladder and the proximal end remains outside the patient's body. An inlet opening is provided at the distal end of the catheter to allow urine to drain into the main lumen and pass into a collection bag associated with the proximal end of the catheter.
Foley catheters are retained within the patient's bladder and urethra by an inflatable balloon located at the distal end of the elongated tube proximate to the inlet opening of the main lumen. An inflation lumen connects the balloon to the proximal end of the catheter so that a liquid may be passed under pressure to the balloon to expand the balloon. A valve is generally provided to maintain the liquid under pressure so that the balloon remains inflated.
Often, a urinary catheter will remain within the urethra for years at a time, presenting general discomfort to the patient. Such discomfort will be heightened when there is relative movement between the catheter and the urethra. This discomfort results from friction between the outer wall of the catheter and the inner wall of the urethra, and is magnified by even minimal movement of the patient. In addition, the internal cardiac rhythm of the body on breathing, turning in bed and walking may create an irritating friction generating movement of the urethra relative to the catheter. This irritation may be compounded by infection, further complicating and lengthening patient recovery. Even greater discomfort will be experienced when the catheter is removed from the urethra after use.
Several prior art devices have been provided to reduce such discomfort through the use of lubricants, as described, for example, in U.S. Pat. Nos. 3,726,281 and 5,098,379. In U.S. Pat. No. 5,209,726, a catheter is disclosed which has an elongated body enclosed by a resilient sleeve which defines a cavity containing a lubricating substance effective to permit the sleeve to slide along the outer surface of the catheter body. Thus, in use, when the catheter body moves in response to movements of the patient's body, the sleeve will move relative to the urethra. However, during insertion and removal of this catheter, significant frictional contact will occur between the sleeve and the urethra, causing considerable discomfort to the patient. The subject invention provides an improvement over these prior art devices.


A mirror heater which is suitable for bathrooms and humid spaces includes electrically insulating layers which are partially provided by double-sided adhesive tapes. The double-sided adhesive tapes fix the various layers to one another and provide an insulative layer.

1. Field of the Invention
The invention relates to a resistance heating device for flat objects such as mirrors.
2. Discussion of the Background
Mirror surfaces often steam up following showering or bathing which prevents the mirrors from fulfilling their function. In order to keep a mirror from steaming up it is known to heat the mirror surface from the rear with heating layers so that the surface does not steam up, even in high air humidity. However, these heating devices have been restricted in countries that impose high safety requirements. For mirror heaters, this may mean that the power-carrying elements, i.e., the heating elements, must be safeguarded by insulating layers which are separated from one another. For example, embedding a serpentine resistance heater between three insulating layers separated from one another on both sides leads to a comparatively thick construction, which in turn results in less efficient heating. The large overall height and the loss of efficiency have kept flat heating devices of this type from becoming widespread, particularly for mirrors.

Resistance heating device for flat objects such as mirrors


A method of creating a burst groove in a burst member is provided. The burst groove following a path, wherein: the groove is created in a plurality of laser scoring stages which are performed in succession to thereby successively increase the depth of the burst groove during each stage; each laser scoring stage involving laser scoring the burst member along at least a portion of the path. The laser scoring in each stage involves laser-energizing a respective region of the burst member with a respective energization width measured perpendicular to the path. In at least one stage the energization width is smaller than the energization width in the immediately preceding stage.

Hydraulic and/or pneumatic systems use pressurized liquid or gas (hydraulic/pneumatic fluid) to accomplish a variety of tasks. Many different industries use hydraulic/pneumatic systems. For example, hydraulic or pneumatic systems may be used in the following industries: oil and gas, biomass, power generation, chemical, pharmaceutical, food and beverage, storage, intermodal containers, aerospace, defense, automotive, solids and bulk handling, medicine, gas and liquid handling, and others. To satisfy the needs of such a broad range of sectors, hydraulic and pneumatic systems have a broad range of operating characteristics and parameters.
For brevity, throughout the remainder of the application we will refer to "hydraulic fluid" and "hydraulic system". "Hydraulic fluid" is intended to cover gas, liquid, and/or vapor unless explicitly stated otherwise. "Hydraulic system" is intended to cover systems that utilize hydraulic fluid.
In a most general sense, a hydraulic system includes a number of active elements (for example, a piston, a pump, or a tank) interconnected by tubes and/or pipes. Hydraulic fluid is contained under pressure within the elements and the tubes/pipes. A given hydraulic system is able to withstand a certain maximum pressure of the hydraulic fluid within the system. If the pressure in the hydraulic fluid exceeds the maximum pressure then damage to parts of the system may occur. An excessively low pressure within a hydraulic system may also cause damage to the hydraulic system. A hydraulic system may also be damaged when the pressure of the hydraulic fluid is outside a desirable operating range.
In the case of a maximum pressure, typically, the interconnecting tubes/pipes of a hydraulic system are able to withstand a greater pressure before they are damaged than the elements that they interconnect.
Because of this potential for damage to a hydraulic system when the hydraulic fluid has a pressure outside a desirable operating range (which could be an over-pressure or under-pressure condition), a protection mechanism is required that reacts to correct the over- or under-pressure situation before the system is damaged.
Burst members provide one such hydraulic system protection mechanism. A burst member is an element in a hydraulic system that is designed to prevent an over- or under-pressure condition in a hydraulic system from persisting for sufficient time for damage to occur. A burst member generally prevents the flow of hydraulic fluid until a certain pressure in the fluid is reached. When that certain pressure is reached, the pressure differential across the burst member is sufficiently high that the burst member ruptures. This rupture forms an aperture in the burst member, through which the hydraulic fluid can flow, thereby relieving the pressure differential that existed across the burst member and relieving the pressure in the hydraulic fluid. A flow of hydraulic fluid through the ruptured burst member serves to allow the pressure in the hydraulic fluid to return to levels at which the system should not be damaged. In an over-pressure situation, the rupturing of the burst member serves to reduce the pressure in the system, thereby reducing the risk of damage due to the high pressure of the hydraulic fluid. In an under-pressure situation, the rupturing of the burst member increases the pressure in the system, thereby reducing the risk of damage due to the low pressure of the hydraulic fluid.
Typically, a burst member is configured to rupture when there is a certain pressure differential across the burst member. It will be understood that a pressure differential is the difference in pressures between opposing sides of a burst member. On one side of the burst member, the pressure may correspond to the air pressure of the surroundings of the system. Equally, both sides of the burst member may be pressurized relative to the surroundings of the system as a whole. What it is important is the pressure differential across the burst member. The pressure differential may be either positive or negative.
A burst member is configured to rupture at a pre-defined pressure differential value. Being able to control this predefined pressure-differential value accurately is important. If the burst member fails to rupture, then damage may occur in the system. On the other hand, if a burst member ruptures when the pressure differential across the burst member is lower than the pre-determined pressure differential, then time is wasted replacing the burst member and re-pressurizing the system, which is undesirable.
Furthermore, because of the catastrophic nature of the rupture of a burst member, it is not possible to produce a burst member with a specific value of pressure differential at which it is guaranteed to burst. Instead, a statistically significant number of identically produced burst members have a range of pressure differential values within which they are expected to rupture. Manufacturers of burst members therefore seek to produce burst members with a narrow range of pressure differential within which a given burst member is expected to rupture.
An ideal burst member therefore has a well-defined (e.g. narrow) specific pressure differential value range within which it should reliably rupture. However, in practice this is difficult to achieve. The pressure differential at which the rupture of a burst member occurs depends on a number of factors. By way of example, these may include: the material of the burst member; the temperature of the burst member, and; the size and shape of the burst member.
A common example of a burst member is a burst disc. A burst disc is generally a circular metal element that is held in position across a vent in a hydraulic system. Under normal conditions (i.e. within the operating range of the burst member), the burst member blocks the vent. When the pressure in the system exceeds a certain value, the burst disc is configured to rupture, thereby opening the vent, which in turn permits the flow of hydraulic fluid through the vent. This flow of hydraulic fluid relieves the pressure in the system. A burst disc may have a variety of shapes and configurations, depending on the intended use and/or pressure rating. For example, a burst disc may be a flat or dome-shaped metal sheet element.
In attempting to produce burst members with a well-defined pressure differential range, a number of methods have been previously proposed.
It is common for manufacturers to form lines of weakness (burst grooves) in the surface of a burst member. These burst grooves attempt to control the pressure differential of rupture for the burst member, and in turn reduce the pressure differential value range within which the burst member is expected to rupture. Burst grooves with a variety of depths, widths and lengths can be formed in an attempt to control the rupture parameters of the burst member.
Mechanically scoring the burst grooves in the surface of a metal burst disc has been proposed. Typically, the burst grooves are formed using a sharp element, for example a knife, which is used to scratch the surface of a burst disc. Forming burst grooves in this manner is difficult to control with high precision, and the consistency of the burst grooves from one burst disc to the next is consequently unreliable.
Using a laser beam to create burst grooves in a layer of resist material that has been applied to burst disc has also been proposed. In this method, a surface of the burst disc is first covered with a resist material. A laser is then used to remove almost completely the resist material along a line on the surface of the burst disc. The burst disc is then electropolished. The absence of laser-removed resist material leaves the metal burst disc exposed to the electropolishing action along a line. The electropolishing partially removes metal along the line defined by the laser, thereby creating a linear recess in the metal of the burst disc. Thus, a burst groove is defined in the surface of the burst disc.
The use of a laser to score directly the surface of a burst disc has also been proposed. In examples of such systems, a laser beam is moved across the surface of a burst disc forming a trench in the surface of the burst disc as it moves.
In such laser scoring of burst discs, laser beams are used to "plough" a single "furrow" forming a burst groove in the burst disc. The parameters of the laser beam control the parameters of the burst groove that is formed. For example, the size and depth of the burst groove is controlled by, for example, the wavelength of the laser, the laser pulse repetition rate, the pulse duration, and the speed of relative motions between the laser and burst disc. The material of the burst member is ablated using the laser, i.e. the action of the laser removes material from the burst member as vapor, without melting or oxidizing material adjacent to the material removed.
In pico-second or nano-second pulsed laser systems, a metal surface of the burst disc is melted by the energy of the laser beam. As the laser beam is moved across the surface of the burst disc, the molten metal can back-fill into the trench formed by the laser. This back filling can impede the formation of the trench in the burst disc by filling in the burst groove, and is accordingly undesirable. This happens because these laser systems do not vaporize the molten metal. Instead, the material is pushed away by the action of the laser beam and solidifies on the sides of the groove, or in the groove after the passage of the laser beam.
When using a pulsed laser system for scoring burst discs there can also be random occurrences of higher energy stray pulses. These stray pulses can pierce through the burst disc entirely, thereby rendering that particular burst disc useless. Even if a stray pulse does not penetrate a burst disc completely, it may still form an unpredictable point of weakness in the burst disc, which in turn could undesirably change the pressure differential at which that particular burst disc will rupture. The occurrence of stray pulses is undesirable, unpredictable and uncontrollable.
When laser scoring thicker materials using fixed power lasers, the scoring process becomes problematic. The surface speed of the beam across the surface of the burst disc has to be reduced to ensure the available energy incident on the surface of the burst member is sufficient to create a melt pool of the metal from which the burst disc is formed. However, this molten metal back-fills the burst groove even as it forms and solidifies, rather than being removed from the burst groove.
A significant problem when laser scoring burst members is how to consistently and repeatedly manufacture burst members with a well-defined pressure differential at which they will rupture. This is especially difficult in thicker burst members.

Method of creating a burst groove by laser scoring


This invention relates to an improved spike installed in a sole of a shoe and consists of a receptacle having a base and several connecting seats integrated around the edge of the base in one piece flexibly moving in proportion to the base. Several spikes are installed unto individual connecting seats extruding the sole. Accordingly, each connecting seat and partial spikes are wrapped up by the flexible sole. When spikes receive an external force causing connecting seats to deviate slightly and simultaneously, the elasticity of the sole material and elastic recovery of each connecting seat are used ingeniously to create proper grip.

1. Field of the Invention
This invention relates to footwear. More particularly, the invention is directed to improve spikes.
2. Description of the Related Art
Spikes are commonly installed on the bottom of footwear for skidproof and grip effects when shoes wearers stand or walk on grass or places with soft soil. Hence, footwear with spikes is mostly designed for exercise doers like track and field and golfing, etc.
Spikes are usually divided into two types. One is single column spikes and the other is disc-shaped spikes. Though several spikes are arranged on the bottoms of shoes for the first type; however, not many spikes are installed on the bottoms due to cost and design. Consequently, this type has single-point grip that is not sufficient. Furthermore, the reacting force is sent back to the feet of the wearers stamping on the ground, which causes discomfort for the wearers. A number of spikes are installed to enhance the skidproof effect for the second type. Nevertheless, the design of a rigid disc with many spikes is only effective in slip resistance without any real grip.


Provided herein are compositions for lowering intracellular pH in a cell or population of cells from a subject comprising contacting the cell or population of cells with a therapeutically effective amount of 5-nonyloxytryptamine or a pharmaceutically acceptable salt, solvate, stereoisomer, or derivatives thereof. These compounds are useful for acidification of cells, including cancer cells, which induces apoptosis and cell necrosis. Methods of use of these compounds, including in pharmaceutical compositions in conjunction with other biologically active agents, in treatment of cancers, including glioblastoma and related neuronal cancers are also included.

Glioma is a common type of primary brain tumor, accounting for about 33% of these tumors. Gliomas originate in the glial cells in the brain. Glial cells are the tissue that surrounds and supports neurons in the brain.
These tumors arise from three different types of cells that are normally found in the brain: astrocytes, oligodendrocytes, and ependymal cells. Gliomas are called intrinsic brain tumors because they reside within the substance of the brain and often intermix with normal brain tissue.
There are different grades of gliomas; however, they are most often referred to as "low-grade" or "high-grade" gliomas. The low or high grade designation reflects the growth potential and aggressiveness of the tumor.
Glioblastoma multiforme (GBM) is the most common and most aggressive malignant primary brain tumor in humans, involving glial cells and accounting for 52% of all functional tissue brain tumor cases and 20% of all intracranial tumors. Despite being the most prevalent form of primary brain tumor, GBM incidence is only 2-3 cases per 100,000 people in Europe and North America. According to the WHO classification of the tumors of the central nervous system, the standard name for this brain tumor is "glioblastoma"; it presents two variants: giant cell glioblastoma and gliosarcoma.
Treatment can involve chemotherapy, radiation, radiosurgery, corticosteroids, antiangiogenic therapy, surgery and experimental approaches such as gene transfer.
With the exception of the brainstem gliomas, glioblastoma has the worst prognosis of any central nervous system (CNS) malignancy, despite multimodality treatment consisting of open craniotomy with surgical resection of as much of the tumor as possible, followed by concurrent or sequential chemoradiotherapy, antiangiogenic therapy with bevacizumab, gamma knife radiosurgery, and symptomatic management with corticosteroids. Prognosis is very poor, with a median survival time of approximately 12-14 months and is almost invariably fatal.
The current therapeutic modality for glioma includes surgery, radiotherapy, and chemotherapy. The most widely used drugs are carmustine, lomustine, vincristine, procarbazine, carboplatin, etoposide and irinotecan. Neoadjuvant or adjuvant therapy with these drugs was shown to prolong disease-free survival but not overall survival. Recently, concurrent temozolomide and radiotherapy has become the new standard of care for patients diagnosed with GBM, prolonging survival from 12 months to 15 months.
However, there still exists a pressing need for novel treatment modalities to treat and cure GBM and related cancers,

5-nonyloxytryptamine and related intracellular PH acidifiers for the treatment and prevention of cancer


High-power electronic components generate significant amounts of heat that must be removed in the course of normal device operations. Certain types of electronic components, such as some monolithic microwave integrated circuits and LEDs, can contain materials that are difficult to effectively bond to a heat gink in order to establish a thermal interface between the two. Device assemblies can include a heat-generating electronic component in thermal communication with a metallic heat sink via a metallic thermal interface layer. The metallic thermal interface layer is disposed between the heat-generating electronic component and the metallic heat sink. The metallic thermal interface layer is formed from a composition including a plurality of metal nanoparticles that are at least partially fused together with one another. Methods for forming a thermal interface layer include heating metal nanoparticles above their fusion temperature and subsequently cooling the liquefied metal nanoparticles to promote bonding of the electronic component.

Ineffective thermal communication between a heat source and a heat sink hampers the dissipation of excess heat from a system, and damage to system components can occur with ongoing heat buildup due to poor heat transfer. Thermal interface materials (TIMs) can be used in many instances to form a more robust thermal connection between an abutted heat source and heat sink to promote better heat transfer between the two, ideally by minimizing the occurrence of contact voids that diminish the efficiency of heat transfer.
Thermal greases, thermal epoxies, and certain types of metal solder are commonly used for forming thermal interfaces between various structures. The degree to which the heat source and heat sink are mechanically held together depends upon the chosen thermal interface material, with thermal greases providing only weak mechanical coupling and thermal epoxies and metal solders providing stronger bonding. Further, the choice of a particular thermal interface material for a given application can be dictated by the properties of the structures between which thermal communication is to be established. Accordingly, there is no one thermal interface material suitable for universal use across a wide variety of platforms.
Some heat sources and heat sinks are particularly difficult to effectively thermally couple due to chemical or physical incompatibility between the two. For example, coefficient of thermal expansion (CTE) mismatch between the thermal interface material, the heat source and/or the heat sink can result in delamination of the coupled structures. Similarly, if the surfaces of the heat source and the heat sink are of a significantly different chemical nature, ineffective mechanical coupling via the thermal interface material can occur. When the surfaces of the heat source and the heat sink are chemically or physically incompatible with one another, conventional materials can often be insufficient for forming an effective thermal interface, and rise of more costly and labor-intensive materials can often become necessary.
High-power, high-frequency electronic circuits, such as those operating in the microwave-frequency range, are one example of a heat source that can be difficult to effectively thermally couple to a heat sink. For example, monolithic microwave integrated circuits (MMICs) only utilize about 10-50% of their input power to produce an output signal, and the remaining power is expended as considerable amounts of heat. Traditional substrates for constructing MMICs can include, for example, Si, GaAs, InP and SiGe. MMICs fabricated from such traditional substrates can usually be bonded to a heat sink using thermal epoxies, such as silver epoxy.
Thermally stable substrates such as GaN and SiC, for example, can enable much higher MMIC operating temperatures. Thermal epoxies can only be used for these types of MMICS when they are operating at less than their maximum possible input power, so as to limit the amount of output heat. For the high, operating temperatures characteristic of full or near-full power-operations, thermal epoxies generally possess inadequate temperature stability, and more robust thermal interface materials such, as AuSn solder, for example, are often used for establishing a thermal interface. AuSn solder, however, is expensive, requires laborious application and curing conditions, and is prone to void formation when flowed. High-power light-emitting diodes (LEDs) can present similar issues to those encountered when working with MMICs. Moreover, intermetallic compound formation can take place during processing of AuSn solder, producing brittle phases such as AuSn4, which can lead to mechanical failure during operation due to factors such as vibration/shock and thermal cycling.
FIGS. 1A and 1B show illustrative images of voids 1 that can commonly occur during the use of AuSn solder 2. FIG. 2 shows a corresponding x-ray image of similar voids that can occur when using AuSn solder, demonstrating that the voids extend in both dimensions in the x-y plane. The voids can decrease the degree of thermal communication that takes place through the thermal interface layer.
In addition to the foregoing difficulties, CTE mismatch usually necessitates the use of specialized copper alloy (e.g., W/Cu or Mo/Cu) heat sinks to match the CTE of the high-temperature MMIC in order to decrease the likelihood of delamination. Such copper alloy substrates are prone to formation of a passivating metal oxide surface layer, which can further complicate the working conditions needed to establish an effective thermal interface layer.
The U.S. Government is actively seeking new means through which the challenges associated with MMICs and other high-power electronic devices can be better addressed, particularly the elimination of AuSn solder in their manufacturing. In view of the foregoing, improved thermal interface layers within device assemblies containing high-power electronic components, such as MMICs and LEDs, and methods for their production, are of considerable interest in the art. The present disclosure satisfies the foregoing need and provides related advantages as well.

High-power electronic devices containing metal nanoparticle-based thermal interface materials and related methods


Receiving an action potential signal associated with a myocardial contraction sensed at a myocardial site, receiving an action potential signal associated with the myocardial contraction sensed at a different myocardial site, comparing a common characteristics of each of the action potential signals wherein the common characteristics relates to at least one member selected from the group consisting of depolarization of tissue at the myocardial sites and repolarization of tissue at the myocardial sites, and, based on the comparing, deciding whether to call for anti-arrhythmia therapy.

Repolarization occurs after myocardial contraction. Electrocardiograms (ECGs) collected from electrodes placed on the surface of a patient's body can exhibit cardiac repolarization and, in particular, repolarization due to contraction of ventricular myocardium. Repolarization associated with normal ventricular contraction is typically referred to as a "T wave". An ECG T wave is representative of a sum of repolarizations of many individual myocardial cells; hence, an ECG T wave exhibits little spatial information. However, where spatial repolarization heterogeneity exists among the many cells, an ECG T wave may exhibit some differences when compared to an ECG T wave from a more homogenous repolarization. In general, exhibited differences in ECG T wave morphology are referred to commonly as T wave alternans (i.e., alternating T wave morphology).
Various studies have linked the presence of T wave alternans to risk of ventricular arrhythmia, a major cause of sudden cardiac death. The link suggests that an increase in heterogeneity of ventricular myocardial repolarization indicates an increased risk of ventricular arrhythmia and possibly even an imminent onset of ventricular arrhythmia. Hence, information contained in an ECG T wave may possibly be used to prevent cardiac death.
Some studies have proposed implantable cardiac pacemakers that use T wave alternans detection. In general, such devices rely on intraelectrocardiograms (IEGMs) rather than surface ECGs to detect T wave alternans. Information exhibited by IEGMs differs from that of surface ECGs because in IEGMs, measurement electrodes are physically and/or electrically more intimately in contact with myocardial tissue. IEGMs typically include information same or similar to waveforms characteristic of cellular action potentials such as monophasic action potentials (MAPs), etc.
While the nature of information in ECGs and IEGMs differs, such devices typically seek to collect and analyze IEGM information to discern T wave alternans in a manner akin to that used for surface ECGs. For example, one study used a unipolar electrode configuration with an electrode in the right ventricular apex because repolarization alternans results from a spatially extended dispersion of ventricular repolarization and because the unipolar voltage vector covers a greater area of ventricular myocardium than standard bipolar recordings. Again, surface ECGs also measure a spatially extended dispersion of ventricular repolarization and have a voltage vector that covers a large area of the ventricular myocardium.
While such spatially extended measurements of ventricular repolarization may prove helpful in assessing risk or imminent onset of arrhythmia, a need exists for techniques that can measure and use local and/or spatial information. Various exemplary methods and/or devices described herein include use of local and/or spatial information.

Anti-arrhythmia therapy based on spatial and/or temporal information


An apparatus for presenting a test chart for testing a visual performance of an eye to be examined, the apparatus comprising a test chart plate including a plurality of test chart pictures provided with a plurality of test charts, and with information about the test charts provided between each test chart picture and the next test chart picture, a case having an opening which is approximately the same size as the test chart picture, and a change-over device for moving the desired test chart picture to the opening of the case.

1. Field of the Invention
The present invention relates to an apparatus for presenting a test chart, which presents a test chart used for testing a visual performance, and more particularly to an apparatus for presenting a test chart suitable for a test in near vision.
2. Description of Related Art
In a visual performance test for a refractive power of an eye to be examined or the like, an apparatus for presenting a test chart, which presents various kinds of test charts, is used, such apparatus is classified into an apparatus for far vision and an apparatus for near vision.
The apparatus for near vision commonly has a simple construction, for example, such apparatus is known that holds a plate in the shape of a disk, which is provided with a plurality of test charts, in a case in the shape of a plate, which is provided with a test chart window, so that the plate may rotate. Referring to the apparatus, if an operator rotates the plate by operating, then the test charts are changed-over and placed in the test chart window.
The operator has to understand details of the test charts and the method of use thereof prior to a test in order to test accurately, however, the test chart differs with manufacturers or type of the apparatus, therefore, it is difficult for the operator to memorize all of them. However, if the test is performed with confirming a manual, a guide book or the like, then it takes much time and disables the operator for smooth test. Further, if the operator loses the manuals or the like, then hindrance may be occurred in the case of an unskilled operator not understanding details of test charts sufficiently.
In addition, there is known such apparatus that has a plate provided with a character denoting its testing distance, as well as test charts, peripherally, however, this character is unnecessary for presentation to the examinee. Moreover, if the examinee gaze at the character, then the eye of the examinee is not fixed to a certain point, as a result, it takes much time to perform the test.


A lens driving device is provided with a holder that holds a lens, a supporting portion that supports the holder displaceably along an optical axis of the lens, and at least one magnet that is arranged symmetrically with respect to the optical axis on side surfaces of the holder. The supporting portion is provided with a coil so as to face toward the magnet. The supporting portion is also provided with a magnetic member so as to face toward the magnet.

1. Field of the Invention
The present invention relates to lens driving devices, and in particular to a lens driving device that is suitably mounted on a small camera or the like to provide auto-focus functionality.
2. Description of the Related Art
Conventionally, various lens driving devices are mounted on optical devices. As known examples of such lens driving devices, there are motor driven actuators utilizing a stepping motor, piezoelectric actuators utilizing piezoelectric distortion when an electric field is applied to a crystalline body, and electromagnetic actuators utilizing a voice coil that are adopted for loudspeakers or the like.
For example, a voice coil lens driving device is mounted on a camera in order to realize auto-focus functionality. With the voice coil lens driving device, a coil is attached to a holder that holds a lens, and a magnet is attached to a base. Application of current to the coil produces electromagnetic driving force. The electromagnetic driving force drives the holder along a direction of an optical axis of the lens.
With the voice coil lens driving device, a spring member that supports the holder may also be used for supplying power to the coil. With this configuration, a wire for power supply to the coil does not have to be drawn from the holder. As a result, undesirable vibration or tensile force may not be applied to the wiring when driving the lens. Therefore, it is possible to suppress a problem that such vibration or tensile force may damage the wiring may be suppressed. On the other hand, however, this configuration has a problem that yield ratio at production of actuators is easily reduced because the configuration of the spring is complicated.
The above problem may be eliminated by attaching the magnet to the holder and the coil to the base. With this configuration, the wiring to the holder is not necessary in the first place, and the damage to the wiring and the like when driving the lens fails to occur. Further, it is possible to simplify the configuration.
However, because a magnet is generally heavier than a coil, attaching a magnet to the holder makes the movement of the holder and the lens difficult. In particular, when the holder is driven in a vertical direction, a difference between downward movement and upward movement is easily generated due to an influence of gravitational force. For example, there may be differences in speeds when starting to move and drive responses between downward movement and upward movement (hereinafter, such a difference in the movement is referred to as a "drive difference"). Therefore, with this configuration, a smooth lens driving may not be realized when moving the holder in a vertical direction.


A roller structure including a cylindrical casing having an outer wear surface and an inner surface provided by a bore extending through the cylindrical casing. At least one anti-friction bearing is positioned within the bore in contact with the inside surface of the cylindrical casing. The anti-friction bearing includes a solid lubricant. In one embodiment, the roller structure is a roller turn roller and is a component of a guide for a turn of a conveyor system, wherein the outer wear surface is for contacting the chain of the conveyer system. A method of lubricating a roller structure is also provided.

The present disclosure generally relates to roller structures. More particularly, in some embodiments, the present disclosure relates to roller turn rollers used in conveyor systems.
Roller turn rollers are utilized in conveyor systems to control and guide the moving components of the conveyor around curves or turns and prevent lateral displacement of such components from the intended course. In a power and free conveyor, for example, a series of such rollers at the inside of a turn hold the power chain in proper horizontal alignment with the free rail of the conveyor system to maintain inter-engagement with driven trolleys. It is common to use oil or grease to lubricate the bearings used in roller turn rollers to extend the service life of the bearing.

Roller structure with anti-friction bearings


The present invention relates to a wavelength division multiplexed (WDM) apparatus for monitoring optical frequencies, allowing optical channel frequency monitoring using the crossover property of an arrayed-waveguide grating and pilot tones that are in wide use in optical communication networks and enhancing efficiency of operation, maintenance, and management of WDM optical communication networks.

1. Field of the Invention
The present invention relates to an apparatus for monitoring optical frequencies using an arrayed-waveguide grating (demultiplexer) in wavelength division multiplexed optical communication networks. More particularly, the invention relates to a wavelength division multiplexed apparatus for monitoring the optical frequencies utilizing an arrayed-wavequide grating and pilot tone signals applied on optical signals in order to enhance the efficiency of operation, administration, and maintenance of wavelength division multiplexed optical communication networks.
In Wavelength Division Multiplexing (WDM) optical communication systems, a plurality of transmission lasers with different wavelengths are multiplexed on a single optical fiber so that the transmission capacity per fiber is enhanced, endowing the network with broadband and high speed.
However, since the optical frequencies of optical signals may change due to the system aging, temperature change, etc. and the optical frequency change on each channel may have a large impact on the system performance by causing a change in channel output power and crosstalk with the adjacent channels due to the different frequency-dependent transmission properties of different optical elements, there is always needed to monitor optical frequencies of each channel in wavelength division multiplexed systems.
2. Description of the Related Art
There has been proposed a technique in the prior art for monitoring optical frequencies of multiple channels in which the wavelength crossover properties of an arrayed-waveguide grating is utilized to monitor optical frequency of optical signals by passing the optical signals through the arrayed-wavequide grating.
However, this technique in the prior art has an economic disadvantage that two arrayed-waveguide grating ports and two photodetectors are required to monitor one optical signal because two optical signals carried on one port of the arrayed-waveguide grating cannot be differentiated.
Another frequency monitoring technique in the prior art applicable to wavelength division multiplexed optical transmission systems uses frequency tunable passband filters such as acousto-optic tunable filters or temperature tunable etalon filters that are able to vary the frequency of the passband.
However, this technique not only requires a delicate tuning mechanism though they allow a simple configuration, but has insufficient reliability and resolution for dense WDM optical systems.
There has been proposed still another simple technique which uses a fixed Fabry-Perot etalon filter and pilot tones for monitoring optical frequencies of multiple channels without using tunable filters and monitors the optical frequencies of the optical signals falling in the vicinity of the resonance frequency of the Fabry-Perot etalon filter.
However, this technique has a disadvantageous degradation in the monitoring performance after passing an optical amplifier due to the cross-gain modulation of erbium-doped optical fiber amplifier (EDFA).

Apparatus for monitoring optical frequencies of WDM signals

Abstract: The present invention provides a WDM apparatus for monitoring optical frequencies comprising optical demultiplexing means for optically demultiplexing optical signals including externally added pilot tone signals, photo-detecting means for photo-electrically converting the output of said optical demultiplexing means, and frequency estimating means for estimating the frequency of the optical signals by measuring the amplitudes of the pilot tones from the output of said photo-detecting means.

Korea Advanced Institute of Science and Technology


An apparatus for creating a panorama is provided, the apparatus including an image obtainer to obtain at least two images via at least two cameras, an overlapping area analyzer to analyze an overlapping area among the at least two cameras, and extract overlapping image information, an image segmentation unit to segment the at least two images in an object unit, and generate image segmentation information, a depth value extractor to extract a depth value of an object in the at least two images, an image focus setter to set a focus value based on the depth value for the plurality of segmented objects, and a panorama creator to create panorama content of which a focus is convertible using the image segmentation information and the focus value.

1. Field of the Invention
The present invention relates to an apparatus and method for creating a realistic sense of panorama content using a focus conversion effect of a panorama image.
2. Description of the Related Art
A panorama image capturing an image through a special optical lens/mirror or a plurality of cameras, and synthesizing the image may provide a viewing angle wider than general image media.
Although a general panorama image may be capable of providing a viewing angle wider than a conventional image, due to an absence of depth information, user navigation available within the panorama image may be merely a simple function of performing a digital zoom in/out and a viewpoint movement.
To overcome such restrictions, recent research is being conducted on various technologies providing a realistic sense of a panorama, such as, stereoscopic panorama, free-viewpoint panorama technology enabling a realistic sensation through creating an image based on a variable viewpoint of a user via image modeling, and the like, in a field of a panorama imaging.
However, use the technologies providing a realistic sense of a panorama is not widespread among real services due to difficulties and intricacies involved with creating and playing panorama content.

Apparatus and method for creating panorama

Electronics and Telecommunications Research Institute


A housing having an extrusion forming a first channel and a second channel; a lighting system in the first channel adapted to direct light away from the first channel; a mounting system in the second channel adapted to couple the extrusion to a vehicle; a first end cap including a first connector, the first end cap being coupled to a first end of the extrusion; a second end cap including a second connector, the second end cap being coupled to a second end of the extrusion; wherein the first connector and the second connector are electrically coupled to one another, and wherein the first connector and the second connector are electrically coupled to the lighting system.

1. Field of the Invention
The present invention relates generally to providing auxiliary lighting systems. More particularly, this invention relates to auxiliary lighting systems for mobile platforms with an integral mounting system.
2. Discussion of the Related Art
A mounted auxiliary light typically consists of one or more light sources in a protective housing. The light sources may be of various types, for example light-emitting diode (LED), high-intensity discharge (HID) or halogen. The protective housing comes with or is configured for a mounting system that allows the external mounted light to be secured to a base. The auxiliary light is typically powered by a wired connection to a battery, for example a vehicle battery.
A mounted auxiliary light is commonly used where the operator of a vehicle requires additional lighting beyond ambient lighting and lighting provided by the vehicle. For example, an off-road vehicle in a location with no exterior lights may require more lighting than that provided by the vehicle's headlights. The auxiliary light may be used in conjunction with, for example, vehicles, aircraft, watercraft, motorcycles, trailers and commercial equipment. The auxiliary light may also be used in a stationary location, for example, in an architectural use.
A mounted auxiliary light may be mounted to a portion of a vehicle or other structure. Because of the variance of structures and mounting locations, it is often desirable to have an adaptable mounting system which accommodates varying mounting locations and allows the external mounted light to rotate about one or more axes.
The user of a mounted auxiliary light may require a cover to, for example, protect the light or change the type of light emitted. Covers may be made of, for example, fabric or plastic and may be transparent or opaque.


A method of operating a resource lock for controlling access to a resource by a plurality of resource requesters, the resource lock operating in a contention efficient (heavyweight) operating mode, and the method being responsive to a request from a resource requester to acquire the resource lock, the method comprising the steps of: incrementing a count of a total number of acquisitions of the resource lock in the contention efficient operating mode; in response to a determination that access to the resource is not contended by more than one resource requester, performing the steps of: a) incrementing a count of a number of uncontended acquisitions of the resource lock in the contention efficient operating mode; b) calculating a contention rate as the number of uncontended acquisitions in the contention efficient operating mode divided by the total number of acquisitions in the contention efficient operating mode; and c) in response to a determination that the contention rate meets a threshold contention rate, causing the resource lock to change to a non-contention efficient (lightweight) operating mode.

A software lock is a mechanism to allow one software thread to execute a block of code, while excluding all other threads from simultaneously executing that same block of code. The thread permitted to execute the code is said to 'possess' the lock, and the block of code is known as a synchronised block. Locks are employed to ensure deterministic program behaviour, a characteristic of thread safety, for synchronised blocks which are shared between threads. A compromise for this provision of thread safety is increased overhead in lock processing. Firstly, locking serialises parts of the code which reduces the potential for a program to run efficiently on multiprocessor (MP) machines. For instance, one or more processors may be blocked from entering a block of code (and hence from doing any work) while a thread possessing the lock executes the synchronised block. This is called contention. Secondly, the operation associated with locking has a high overhead, especially when there is no actual contention. In this situation, locking is required due to a possibility of contention, although contention may not actually exist.
Two categories of lock are employed: a "lightweight lock", and a "heavyweight lock," Lightweight locks avoid high overhead when there is no contention, but perform poorly when there is contention. Lightweight locks are usually implemented using one or more primitive machine instructions and are strongly associated with good hardware support. Heavyweight locks have relatively high overhead when there is no contention, but perform very well when there is contention. Heavyweight locks are often implemented in software, such as through a call to a thread library, kernel, or operating system, and are supported more by algorithms such as queues and schedulers rather than hardware. The heavyweight lock requires significantly greater memory storage, and many more machine operations,
In some software a software lock has a bimodal existence between a lightweight mode and a heavyweight mode. Bimodal existence of locks is explored in detail in the paper "A Study of Locking Objects with Bimodal Fields" (Tamiya Onodera and Kiyokuni Kawachiya, 1999). Initially, the lock is stored as a lightweight lock. When contention occurs, the lock is changed to a heavyweight lock. This change of mode from lightweight to heavyweight is known as lock inflation. The reverse transition, deflation from a heavyweight to a lightweight mode, occurs when certain conditions are satisfied. One of these conditions is that the lock is no longer contended. The process of inflation and deflation allows the best of both worlds: when the lock is inflated it performs well when there is contention; and when it is deflated it performs well when there is no contention.
Typically, deflation will occur as soon as a lock ceases to be contended. This is known as quick-deflation because the deflation occurs at the first opportunity in the absence of further contention. This can be effective where contention is infrequent, but a high frequency of changes between contended and uncontended periods for a lock (intermittent contention) can result in a corresponding high frequency of inflation and deflation of the lock. Intermittency is a chaotic phenomenon whereby periods of one state are punctuated by periods of another state. This may be seen on the small scale, where locks change state frequently between contended and uncontended states, which we call intermittent contention, or on the large scale where long periods of high contention are mixed with long periods of no contention, and also with periods of intermittent contention. A lock that exhibits periods of no contention, high contention, and intermittent contention is referred to as an intermittent lock. Inflation is a relatively expensive process (having a large overhead) and frequent inflation is itself a cause of poor performance in a running software application. Thus intermittent contention causes quick-deflation to be an inefficient algorithm because it causes frequent inflation.
For this reason, software can implement a modification to the quick-deflation policy in which, for each lock, a count is maintained of a number of times that the lock is inflated. When this count exceeds a threshold the lock is prevented from being deflated forever more. This is known as 'sticky' inflation. Thus an intermittent lock will eventually become inflated and stay inflated, but for a non-intermittent lock (i.e. a lock which is either contended or uncontended, but not both) the bimodal behaviour of inflation and deflation ensures that the lock is in an appropriate mode. Sticky inflation resolves the problem of high frequency inflation due to intermittent contention, however an intermittent lock is not fully optimised once sticky inflation has taken place because there is no opportunity to deflate the lock in the event that the lock ceases to demonstrate intermittent contention. Intermittent locks can experience highly chaotic behaviour: sometimes uncontended; sometimes contended; and sometimes intermittent. During intermittent periods it will be best for the lock to be either inflated or deflated depending on the degree of contention. During the uncontended periods, it will be best for the lock to be deflated. During the contended periods it will be best for the lock to be inflated. However the sticky inflation policy does not take into account these situations.
An improvement to sticky inflation is available which resets the inflation count to zero after a certain period. Whilst this can remove the drawback of sticky inflation after the certain period, a definition of the appropriate period is difficult to arrive at. For example a count can be reset after each execution of a Garbage Collector routine for the disposal of unused software entities, such as objects. However, there is no formal relationship between the behaviour of a lock and occurrences of garbage collection. Furthermore there is no good criterion for deciding when a lock's inflation count should be reset. Sticky inflation with such an improvement also necessitates two parameters: a parameter to determine when inflation should be sticky; and a threshold parameter to determine when deflation should occur.
Thus it would be advantageous to provide a scheme for the inflation and deflation of locks, which provides for intermittent locks remaining bimodal, allowing them to be inflated when contended and deflated when uncontended, and further allowing for locks to remain either inflated or deflated depending on a degree of contention when the contention is intermittent.

International Business Machines Corporation


A fluid control system for a rotating shaft which provides a seal to limit fluid leakage from around the shaft and which vacuums away any fluid leaking past the provided seal. The fluid control system may be installed around a rotating shaft such as a flywheel in a press. The fluid control system includes a housing which forms a clearance space with the rotating shaft in which fluid, such as oil being used to create or service the flywheel bearing, can be collected. A seal is provided between the rotating shaft and the housing to prevent fluid leakage from the clearance space. A vacuum mechanism positioned along a leakage path beyond the seal is provided with an air duct through which passes a vacuum induced air flow which vacuums away fluid leaked from the seal. The air duct is preferably configured to include a radial clearance between a portion of the fluid collection system and the rotating shaft such that relative axial movement therebetween does not compromise the vacuuming capabilities of the vacuum mechanism, and therefore the fluid collection system can be employed with axially reciprocating or moving rotating shafts.

The present invention pertains to a fluid control system, and, in particular, to a system for controlling oil or other lubricating liquid fluid leakage on a rotating shaft or flywheel in a device such as a mechanical press. The shaft or flywheel may also be subjected to axial movement.
Mechanical presses, such as straight side presses and gap frame presses for stamping and drawing, generally include a frame having a crown and bed and a slide supported within the frame for reciprocating motion toward and away from the bed. The slide is typically driven by a crankshaft having a connecting arm connected to the slide, to which is mounted the upper die. Rotation of the crankshaft moves the connecting rods to effect straight reciprocating motion of the slide. The lower die is conventionally mounted to a bolster which, in turn, is connected to the bed. Such mechanical presses are widely used for blanking and drawing operations and vary substantially in size and available tonnage depending on their intended use.
The primary apparatus for storing mechanical energy in a press is the flywheel. The flywheel and flywheel bearing are normally axially mounted on either the driveshaft, crankshaft, or the press frame by use of a quill. The flywheel is typically mounted at one end of the crankshaft and connected by a belt to the output pulley of a motor such that when the motor is energized, the massive flywheel rotates continuously. The motor replenishes the energy that is lost or transferred from the flywheel during press operations. When the clutch engages the flywheel to transmit rotary motion of the flywheel to the crankshaft, the flywheel drops in speed as the press driven parts are brought up to press running speed.
During clutch engagement, dry and clean clutch linings free from oils or lubricants are necessary to reduce the time necessary to bring the driven parts up to press running speed, and lower times translate to fewer bad parts being produced by the press. Clean, dry brake linings are also necessary for reduced stopping time, and lower stopping times similarly result in fewer unacceptable parts being produced. Also, containing oil or lubricant spillage from leaking flywheel bearings is desirable to keep the local environment clean.
When a flywheel is mounted on a quill journal, seals and various O-rings have typically been placed throughout the quill journal area to reduce the likelihood of oil and lubricant present at the flywheel bearings from migrating to the clutch and brake lining areas. These types of oil control means are passive is and work only so long as the seals and O-rings maintain their integrity. External factors such as seal damage due to installation, contamination, corrosion, or seal compression set may degrade the ability of the seals or O-rings to retain oil. Ultimately a leak may occur which wets the clutch or brake linings and thereby results in inefficient operation of the press.
In a variety of sealing devices known in the art, vacuum pressures have been employed to aid in removing oil which has passed by the seals. For example, in a prior art press disclosed in U.S. Pat. No. 5,467,705, a drain port connected to a vacuum source is used to vacuum oil from around a non-rotating, reciprocating shaft that has leaked past a shaft seal.
In particular, vacuuming oil from certain portions of rotating shafts is assisted by the rotation of the shaft. Centrifugal forces associated with shaft rotation tend to fling oil from those shaft surfaces which are axially aligned, and consequently a radially aligned vacuum port may function satisfactorily. However, vacuuming away fluids present on the ends of the shafts, for example on the side of a flywheel, may be complicated if the centrifugal forces tend to throw the fluid past a conventionally mounted vacuum inlet.
Another difficulty with using vacuum pressures to induce an air flow to vacuum fluid off the radially extending surface of a flywheel is that selected clearances should be held to optimize the air flow. Variations in the relative positions of the vacuum housing and flywheel can result in an air flow inadequate to vacuum off the fluid. However, as a slight play in the flywheel mounting may be possible, or the flywheel may be designed to axially shift during its operation, as disclosed in co-pending application Ser. No. 08/537,996, it would be desirable for fluid control systems using vacuum pressures to account for this axial movement.
Thus, it would be desirable to provide a mechanical press having a fluid control system for a rotating component which overcomes the shortcomings described above.

Fluid control system for rotating shaft or flywheel