A photonic concentrator is used to connect to a telecommunication network subscriber terminals sending and receiving data in the form of fixed length cells using asynchronous time-division multiplexing, in particular on an optical fiber. The concentrator comprises, for processing cells from a subscriber terminal, a time-division and non-synchronous statistical spectral multiplexing stage, a synchronization to a local clock stage, a spectral multiplexing and bit rate converter stage, and a periodic time-division multiplexing stage. To process cells addressed to subscriber terminals it comprises a periodic time-division demultiplexing, spectral multiplexing and bit rate adjuster stage, a bit rate converter stage and a spectral demultiplexing stage. The concentrator has applications in telecommunication networks.

1. Field of the invention
The invention concerns a photonic concentrator for connecting subscriber terminals to a telecommunication network using asynchronous time-division multiplexing. This type of multiplexing enables all kinds of information to be transmitted in a single form comprising packets of bits of fixed length called cells. It is known to connect subscriber terminals to a telecommunication network using concentrators whose function is to concentrate calls from relatively lightly loaded subscriber circuits onto more heavily loaded multiplexes. Conversely, a concentrator takes calls from a heavily loaded multiplex and transfers them onto a line connected to a subscriber terminal which is relatively lightly loaded.
2. Description of the prior art
French patent application No 2 646 036 describes an all electronic digital subscriber access unit comprising a plurality of concentrators for connecting subscriber terminals using various transmission techniques, including asynchronous time-division multiplexing, to a telecommunication network. In these known type concentrators, each concentrator comprises subscriber access circuits and two concentrator stages.
Each subscriber access circuit provides functions including:
optical-electronic conversion and vice versa for each subscriber terminal connected to the concentrator by an optical fiber line;
delineation of the cells received from the subscriber terminal, by which is meant the identification of the start of each cell;
descrambling of the data field of each cell received from a subscriber terminal;
scrambling of the data field of each cell sent by the concentrator to a subscriber terminal;
calculation of the error detection word relating to the header of each cell sent from the concentrator to a subscriber terminal or received from a subscriber terminal;
resynchronization of the cells sent by a subscriber terminal to a local clock of the subscriber access unit;
a policing function which monitors the output bit rates of the subscriber terminals;
extracting signalling cells from the cells sent by a subscriber terminal and injecting signalling cells into the cells sent by the concentrator to a subscriber terminal;
conversion of the virtual circuit and virtual circuit group labels included in each cell sent by a subscriber terminal;
calculation of the routing label for routing each cell in the switching network and insertion of this label in front of the cell header;
elimination of empty cells sent by a subscriber terminal; and
insertion of empty cells into the cells sent from the concentrator to the subscriber terminals.
The first stage of concentration comprises an asynchronous time-division switching matrix controlled by a microprocessor. The second stage of concentration comprises another asynchronous time-division switching matrix or a time-division multiplexer-demultiplexer controlled by a microprocessor.
The design of this concentrator is optimized for use of electronic components but is not optimized for use of photonic components. These have the advantage of a higher speed and enable spectral multiplexing. Retaining the design of known type concentrators would result in underuse of the performance capabilities of photonic technology.
An object of the invention is to propose a photonic concentrator whose design is not merely deduced from that of a known electronic concentrator but which is optimized for the use of photonic components.


An address region of an internal bus wherein a burst access can be utilized in an external bus is set in an address table. A DMA control unit determines whether or not a burst access can be utilized in the external bus by comparing an address in an access to the internal bus with an address region set in the address table. Then, the DMA control unit carries out a direct memory access transfer by utilizing a burst access when it is determined that the burst access can be utilized in the external bus. Accordingly, the DMA control unit can carry out a DMA transfer by using a burst access without the intervention of a FIFO memory and it becomes possible to carry out a high speed DMA transfer.

1. Field of the Invention
The present invention relates to a DMA (direct memory access) controller for directly controlling a data transfer between memories, or the like, without the process of the CPU (central processing unit) and the control method thereof, in particular, to a DMA controller for controlling a burst access in an external bus at the time of DMA transfer between an internal bus and an external bus and the control method thereof.
2. Description of the Background Art
In recent years information processing apparatuses such as personal computers have spread widely and the demand for higher processing speed and a greater number of functions has increased. A DMA which directly carries out data transfer between memories without the process of the CPU can be cited as a function which implements a higher processing speed of an information processing apparatus. In the following, a configuration and an operation of a conventional DMA controller are described.
(Configuration of Conventional DMA Controller)
FIG. 1 is a block diagram showing a schematic configuration of a conventional DMA controller. This DMA controller includes a transfer source address register 10 for storing the transfer source address of the DMA, a transfer destination address register 11 for storing the transfer destination address of the DMA, a DMA transfer counter 12 for storing the number of bytes of the data to be DMA transferred, a DMA request selection register 13 for selecting a request signal which starts up the DMA, a DMA control unit 50 for carrying out a DMA transfer by accessing an external memory, which is not shown, a DMA request detection unit 60 for detecting a DMA request from outside in accordance with the setting of DMA request selection register 13 and a FIFO (first in first out) memory 70 for temporarily storing data read out by DMA control unit 50.
Signals 100 to 104 indicated to the left of the DMA controller are signals at the time when an external bus master such as a CPU accesses transfer source address register 10, transfer destination address register 11, DMA transfer counter 12 or DMA request selection register 13 and include a chip select (CS) signal 100 for indicating that the access is valid, 32 address (ADDR [31:0]) signals 101 for selecting the registers to be accessed, a read/write control (RW) signal 102 for indicating whether the access is a read access or a write access, 32 write data (WDATA [31:0]) signals 103 for transferring data for a write access and 32 read data (RDATA [31:0]) signals 104 for transferring data for a read access.
Signals 110 to 115 indicated to the right of the DMA controller are signals for accessing buses inside of the semiconductor chip in which the DMA controller is incorporated (hereinafter referred to as internal buses) and include 32 internal address (IADDR [31:0]) signals 110 for selecting regions to be accessed, an internal read/write control (IRW) signal 111 for indicating whether the access is a read access or a write access, 32 internal write data (IWDATA [31:0]) signals 112 for transferring data for a write access, 32 internal read data (IRDATA [31:0]) signals 113 for transferring data for a read access, an internal ready (IREADY) signal 114 for indicating that the bus access has been completed and an internal bus access request (IREQ) signal 115 for requesting the internal bus to make an access.
In addition, signals 120 to 126 indicated to the right of the DMA controller are signals for carrying out an access request to an external bus interface, which is not shown, connected to a bus (hereinafter referred to as external bus) outside of the semiconductor chip in which the DMA controller is incorporated and include 32 external address (EADDR [31:0]) signals 120 for selecting regions to be accessed, an external read/write control (ERW) signal 121 for indicating whether the access is a read access or a write access, 32 external write data (EWDATA [31:0]) signals 122 for transferring data for a write access, 32 external read data (ERDATA [31:0]) signals 123 for transferring data for a read access, an external ready (EREADY) signal 124 for indicating that the bus access has been completed, an external bus access request (EREQ) signal 125 for requesting an external bus to make an access and an external burst request (EBURST) signal 126 for requesting an external bus interface to make a burst access.
In addition, a DMA request signal (DMAREQ [31:0]) 130 for accepting a DMA request and a clock (CLK) signal 150 utilized in the entire system are included as other signals.
(Operation of Conventional DMA Controller)
(1) Setting of DMA
The setting of a DMA is carried out by the CPU by writing values in the internal registers (transfer source address register 10, transfer destination address register 11, DMA transfer counter 12 and DMA request selection register 13) of the DMA controller.
FIG. 2 is a timing chart when the CPU writes a value in the internal register of the DMA controller. The internal register receives a value of ADDR [31:0] 101 at the rising edge of CLK signal 150 in cycle 1 in the case where it is detected that CS signal 100 is at a high level (hereinafter merely denoted as "H") and that RW signal 102 is at a low level hereinafter merely denoted as "L"). The decode result of this ADDR [31:0] 101 determines which register is accessed. Then, the value of WDATA [31:0] 112 is written into the register that is selected by the address which is received.
A transfer source address of the DMA is set in transfer source address register 10, a transfer destination address of the DMA is set in transfer destination address register 11 and the byte number of the data to be transferred by the DMA is set in DMA transfer counter 12. In addition, each bit of DMA request selection register 13 corresponds to, respectively, 32 signals included in DMAREQ [31:0] 130 and "1" is set at the bit corresponding to a signal which starts up the DMA.
(2) Start-Up of DMA
DMA request detection unit 60 starts a DMA transfer at the rising edge of a signal, from among signals included in DMAREQ [31:0] 130, which corresponds to the bit set to "1" in DMA request selection register 13. When DMA request detection unit 60 detects the rising edge, DMA control unit 50 is notified of this.
(3) Carrying Out of DMA
When a DMA request is detected by DMA request detection unit 60, DMA control unit 50 carries out a DMA transfer. FIG. 3 is an example of a timing chart of a conventional DMA controller at the time of DMA transfer. Here, transfer source address register 10 is set to "0x00000000," transfer destination address register 11 is set to "0x80000000" and DMA transfer counter 12 is set to "0xC."
Addresses "0x00000000" to "0x7FFFFFFF" are fixed as addresses of an internal bus while addresses "0x80000000" to "0xFFFFFFFF" are fixed as addresses of an external bus. DMA control unit 50 determines whether a transfer source address and a transfer destination address are in an internal bus or in an external bus, respectively, according to the most significant bit of the addresses stored in transfer source address register 10 and transfer destination address register 20.
In cycle 1, DMA control unit 50 asserts IREQ signal 115 of the internal bus and outputs the first transfer source address to IADDR [31:0] 110 so as to start a read access to the internal bus. At this time, DMA control unit 50 outputs a "H" to IRW signal 111 and gives notification of the read access.
In cycle 2, IREADY signal 114 of the internal bus becomes of "H" and notification is made that the internal bus access is completed. At the end of this cycle, DMA control unit 50 writes the value of IRDATA [31:0] 113 in FIFO memory 70.
In cycle 3, second read access is started with the internal bus, EREQ signal 125 is asserted to an external bus interface, the first transfer destination address is outputted to EADDR [31:0] 120, the data read out from FIFO memory 70 is outputted to EWDATA [31:0] 122 and a write access to the external bus interface is started. At this time, DMA control unit 50 outputs a "L" to ERW signal 121 and makes notification that the access is a write access. In this cycle 3, a "H" is outputted to EREADY signal 124 by the external bus interface so that notification is made that the external bus access is completed.
In the following, in the same manner as in the above, in cycle 4, the second read access to the internal bus is completed and the data from the internal bus is written into FIFO memory 70. In cycle 5, the third read access to the internal bus is started and the second write access to the external bus interface is carried out. In cycle 6, the third-time read access to the internal bus is completed and data from the internal bus is written into FIFO memory 70. In cycle 7, the third write access to the external bus interface is carried out so as to complete the DMA transfer.
FIG. 4 shows another example of a timing chart of a conventional DMA controller at the time of DMA transfer. In this timing chart, the write access to the external bus interface is carried out in a burst access mode. Here, "0x00000000" is set in transfer source address register 10, "0x80000000" is set in transfer destination address register 11 and "0x10" is set in DMA transfer counter 12. DMA control unit 50 determines whether a transfer source address and a transfer destination address are in an internal bus or in an external bus, respectively, according to the most significant bit of the addresses stored in transfer source address register 10 and transfer destination address register 11.
In cycle 2, DMA control unit 50 asserts IREQ signal 115 of the internal bus and outputs the first transfer source address to IADDR [31:0] 110 so as to start a read access to the internal bus. At this time, DMA control unit 50 outputs a "H" to IRW signal 111 and gives notification that the access is a read access. In this cycle, IREADY signal 114 of the internal bus becomes of "H" and notification is made that the internal bus access is completed. At the end of this cycle, DMA control unit 50 writes the value of IRDATA [31:0] 113 into FIFO memory 70.
In cycle 3, IADDR [31:0] 110 is updated and second read access to the internal bus is started. Similar operations are carried out in cycles 4 and 5 and four read accesses to the internal bus are carried out so that respective data is written into FIFO memory 70. At the end of cycle 5, IREQ signal 115 is negated and the read access to the internal bus is completed.
In cycle 6, DMA control unit 50 asserts EREQ signal 125 and EBURST signal 126 of the external bus and outputs the first transfer destination address to EADDR [31:0] 120 so that a write access to the external bus interface is started. At this time, DMA control unit 50 outputs a "L" to ERW signal 121 and makes a notification that this access is a write access. DMA control unit 50 reads out data stored in FIFO memory 70 and outputs the data to EWDATA [31:0] 122. In this cycle, EREADY signal 124 of the external bus becomes of "H" and notification is made that the external bus access is completed.
In cycle 7, EADDR [31:0] 120 is updated and second write access to the external bus is started. Similar operations are carried out in cycles 8 and 9 and the four write accesses to the external bus are carried out so that respective data stored in FIFO memory 70 is outputted to the external bus interface. At the end of cycle 9, EREQ signal 125 and EBURST signal 126 are negated and the write access to the external bus is completed.
However, in the case that a DMA transfer from the internal bus to the external bus is carried out by using the above described conventional DMA controller, FIFO memory 70 becomes indispensable when the burst access to the external bus is faster than the access to the internal bus. That is to say, when a DMA transfer from the internal bus to the external bus is attempted to be carried out without using FIFO memory 70, the speed of the read access to the internal bus cannot keep up with the speed of the burst access to the external bus so that failure of reading data occurs and correct data transfer cannot be carried out.
In addition, in the case that a DMA transfer from the external bus to the internal bus is carried out by using the above described conventional DMA controller, when the burst access to the external bus is faster than the access to the internal bus and when a DMA transfer from the external bus to the internal bus without using FIFO memory 70 is attempted to be carried out, the speed of the write access to the internal bus cannot keep up with the speed of the burst access to the external bus so that an overflow occurs and correct data transfer cannot be carried out.
In addition, in the conventional DMA controller the cycle number required for one access to the internal bus cannot be predicted and, therefore, in the case that a burst access is requested for the external bus interface, it is necessary to carry out a data transfer by using FIFO memory 70 regardless of the actual cycle number required for the access to the internal bus.
Furthermore, in the case that the amount of data to be transfer red by using FIFO memory 70, in particular the maximum amount of data to be transferred that is allowed in the DMA transfer, exceeds the capacity of FIFO memory 70, the control of the DMA transfer becomes complicated due to reasons such that it is necessary to carry out one DMA transfer request by dividing into a plurality of DMA transfers.
Because of the above reasons, there is a problem that an expensive FIFO memory 70 must be mounted in the DMA controller and the cost for the DMA controller becomes high.

Direct memory access controller for carrying out data transfer by determining whether or not burst access can be utilized in an external bus and access control method thereof


A system for extracting useful energy from two masses of matter having polarized hot and cold temperatures operates in its primary embodiment with a looped circulation passageway having a condensing phase, an expansion phase and a working generally gaseous fluid that circulates through the loop. The expansion phase of the gas contains a relatively standing liquid through which the working gas, which is injected at the bottom, is allowed to buoy up to drive gas pressure turbines and principally a flotation turbines (floturbines).. The rest of the loop defines a return path which includes the condensing phase in which the expanded gas from the end of the last turbine is condensed to either a denser gas or to a liquid, and re-injected into the bottom of the condensation phase again, in a continuous cycle. Net energy output is achieved by heating the vertical expansion phase side of the loop with heat from the high temperature source to further expand the working gas and thereby increase the power that it delivers to the turbines, while using the cold temperature source to cool the working fluid in the condensing side, reducing the energy for reinjection.

There are many different kinds of specialized generators for extracting energy from nature one way or another, including tidal generators, ocean current, wave, and temperature differential generators, lightening generators, waterfall generators, and even a gyro generator.
All of these apparatuses are specialized in their requirements for an energy source, some relying on hot water from thermal wells, others needing a 20-foot tide differential. Current generators require water currents, wave generators require waves, and so forth.
However, one source of energy that is virtually universal is the temperature differential. Geothermal heat, solar heat, waste combustion exhaust gas, industrial heat discarded as a by-product, etc. are sources of thermal differentials when paired specifically with lower temperature sources as cool ocean or river currents or even with wind. Stratified ocean layers, and night/day differentials in deserts offer energy opportunities. All that is needed to produce energy, aside from a mechanism to do it, is a temperature differential between two masses as set out in the second law of thermodynamics.
A government effort dubbed "OTEC", for "Ocean Thermal Energy Conversion" has achieved limited success with ocean thermal differentials, reaching at least break-even outputs, which is rather impressive considering the limitation on efficiency predicted by the second law of thermodynamics based on the relatively narrow temperature spread. Nonetheless this system is based on the continuous availability of the hot and cold temperature sources and as a very large fixed plant, no doubt must be worked all the time to have a hope of breaking even commercially.
There is a need for a versatile energy producing system buildable for one or more houses or cities capable of taking advantage of these limitless polarized temperature combinations to efficiently produce clean, competitive energy from mixed and erratic sources. Along these lines little attention has been paid to the use of buoyancy generators, especially in regard to their use transducing energy from thermal differentials. Buoyancy wheels or turbines have been suggested for limited applications in which gas is escaping from the sea floor, but have not been considered realistic for generalized transduction of thermal energy, which would require the creation of a man-made bubble path for a circulating gas.
Examples of buoyancy wheels are shown by U.S. Pat. No. 4,363,212, issued Dec. 14, 1982, and another example is shown in U.S. Pat. No. 4,981,015 issued Jan. 1, 1991. Both disclose flotation wheels whose design requires more energy input than the output energy they would yield, relying on a nondisclosed source of flotation energy having no creation cost.

Buoyancy and thermal differentials energy generator


According to one embodiment, an optical device includes a plurality of optical elements arrange in array. At least of the optical elements includes an optical layer constituted by a plurality of patterns. The plurality of patterns are formed by a layered body including metal layers and a dielectric layer interlayered between the metal layers, and formed as a plurality of regularly-arranged loop-like patterns with a density decreasing from the center toward the periphery of the loop.

Demands for higher quality images in complementary metal-oxide-semiconductor (CMOS) image sensors have been increasingly raised in recent years, and miniaturization of pixels is indispensable to realize high-resolution images. In addition, a low-back-type CMOS image sensor has also been sought, and the problem of peripheral light loss which is referred to as shading in the CMOS image sensor has become more serious. To solve this problem, a structure such as a digital microlens has been proposed recently for use as a microlens to be arranged at each pixel.
A digital microlens provides a refractive-index-distributed-type lens that controls an overall refractive index distribution by adjusting the cycle and pitch of a grating-type high-refractive-index material and a low-refractive-index material (which may be air). Accordingly, it has been considered that adverse effect caused by a shading effect can be improved more than before by making a distribution of the refractive index different between the center and the periphery of a pixel.
The digital microlens in the past, however, uses existing materials and has a problem that a light collecting characteristic would be deteriorated, because a sufficient refractive index cannot be attained in the course of miniaturization of pixels.
A metamaterial has been proposed as a high-refractive-index material. This high-refractive-index material has been provided by layering a metal and an insulating material even in the terahertz band, and by arranging an I-type pattern periodically to thereby realize a material having a high refractive index widely on a very "positive" side.

Optical device and solid-state image sensing device


A cryopump having a cryopump chamber includes a purge gas valve coupled to the cryopump chamber for supplying a first quantity of warm gas to the cryopump chamber in order to purge the cryopump chamber during regeneration. A roughing valve couples the cryopump chamber to a roughing pump enabling the cryopump chamber to be roughed. An exhaust valve is coupled to the cryopump chamber for exhausting gases from the cryopump chamber during purge. A delivery valve is coupled to the exhaust valve for delivering a second quantity of warm gas directly onto surfaces of the exhaust valve for warming the surfaces of the exhaust valve.

Cryogenic vacuum pumps, or cryopumps, currently available generally follow a common design concept. A low temperature array, usually operating in the range of 4 to 25 K, is the primary pumping surface. This surface is surrounded by a higher temperature radiation shield, usually operated in the temperature range of 60 to 130 K, which provides radiation shielding to the lower temperature array. The radiation shield generally comprises a housing which is closed except at a frontal array positioned between the primary pumping surface and a work chamber to be evacuated.
In operation, high boiling point gases such as water vapor are condensed on the frontal array. Lower boiling point gases pass through that array and into the volume within the radiation shield and condense on the lower temperature array. A surface coated with an adsorbent such as charcoal or a molecular sieve operating at or below the temperature of the colder array may also be provided in this volume to remove the very low boiling point gases such as hydrogen. With the gases thus condensed and/or adsorbed onto the pumping surfaces, a vacuum is created in the work chamber.
In systems cooled by closed cycle coolers, the cooler is typically a two-stage refrigerator having a cold finger which extends through the rear or side of the radiation shield. High pressure helium refrigerant is generally delivered to the cryocooler through high pressure lines from a compressor assembly. Electrical power to a displacer drive motor in the cooler is usually also delivered through the compressor or a controller assembly.
The cold end of the second, coldest stage of the cryocooler is at the tip of the cold finger. The primary pumping surface, or cryopanel, is connected to a heat sink at the coldest end of the second stage of the cold finger. This cryopanel may be a simple metal plate or cup or an array of metal baffles arranged around and connected to the second-stage heat sink. This second-stage cryopanel also supports the low temperature adsorbent.
The radiation shield is connected to a heat sink, or heat station, at the coldest end of the first stage of the refrigerator. The shield surrounds the second-stage cryopanel in such a way as to protect it from radiant heat. The frontal array is cooled by the first-stage heat sink by attachment to the radiation shield or, as disclosed in U.S. Pat. No. 4,356,810, through thermal struts.
After several days or weeks of use, the gases which have condensed onto the cryopanels, and in particular the gases which are adsorbed, begin to saturate the cryopump. A regeneration procedure must then be followed to warm the cryopump and thus release the gases and remove the gases from the system. As the gases evaporate, the pressure in the cryopump increases, and the gases are exhausted through a relief or exhaust valve. During regeneration, the cryopump is often purged with warm nitrogen gas. The nitrogen gas hastens warming of the cryopanels and also serves to flush water and other vapors from the cryopump. Nitrogen is the usual purge gas because it is relatively inert, and is available free of water vapor. It is usually delivered from a nitrogen storage bottle through a transfer line and a purge valve coupled to the cryopump.
After the cryopump is purged, it must be rough pumped to produce a vacuum around the cryopumping surfaces and cold finger which reduces heat transfer by gas conduction and thus enables the cryocooler to cool to normal operating temperatures. The roughing pump is generally a mechanical pump coupled through a fluid line to a roughing valve mounted to the cryopump.
Control of the regeneration process is facilitated by temperature sensors coupled to the cold finger heat stations. Thermocouple pressure gauges have also been used with cryopumps. Although regeneration may be controlled by manually turning the cryocooler off and on and manually controlling the purge and roughing valves, a separate regeneration controller is used in more sophisticated systems. Wires from the controller are coupled to each of the sensors, the cryocooler motor and the valves to be actuated. A cryopump having an integral electronic controller is presented in U.S. Pat. No. 4,918,930.
In a fast regeneration process, the second stage of the cryopump is heated as purge gas is applied to the cryopump. As the second stage of the cryopump is warmed, the gases trapped at the second stage are released and exhausted through a relief valve.
A problem sometimes encountered during the fast regeneration process is that some of the gases exhausted through the exhaust valve (such as nitrogen) freeze the surfaces of the exhaust valve. The frozen surfaces can prevent the exhaust valve from sealing properly, thereby affecting the performance of the cryopump.

Cryopump with gas heated exhaust valve and method of warming surfaces of an exhaust valve


A device and method for preventing settlement of particles on a chemical-mechanical polishing pad is provided. Specifically, a device capable of preventing settlement of particles on the pad is located between the polishing pad and a platen of a chemical-mechanical polishing apparatus.

1. Field of the Invention
The present invention is directed to a device and method for preventing settlement of particles on a chemical-mechanical polishing pad, and more particularly, to a device placed between the polishing pad and a platen of a chemical-mechanical polishing apparatus used during the fabrication of semiconductor devices.
2. Discussion of the Prior Art
During fabrication of semiconductor devices, irregular top surfaces result due to many manufacturing processes, such as forming conductive lines and single or multiple layers. During various stages of semiconductor wafer production, irregular top surfaces of the wafers are planarized or flattened to provide smooth surfaces. Planarized surfaces improve performance and yield of integrated circuits formed on the wafer.
Chemical-mechanical polishing (CMP) is one method to planarized wafer surfaces. In the CMP process, the wafer is rubbed with a polishing pad. The rubbing is accomplished by pressing the wafer or polishing pad toward each other, and rotating one or both of them relative to each other. A slurry is used to chemically/mechanically attack the wafer surface and facilitate removal thereof by the mechanical abrasion provided by the rotating polishing pad.
Particles are generated from wafer abrasion (i.e., the mechanical abrasion of the wafer surface being polished), from slurry agglomeration (i.e., slurry particles that coalesce, which slurry particles are approximately 0.05 microns in size), and from pad debris resulting from polishing pad disintegration. These particles embed or settle within the polishing pad fabric, and protrude during the polish process causing wafer scratching, defects and improper planarazation.
Furthermore, the embedded particles change the surface structure of the polishing pad, resulting in process instability, and reduced repeatability and polish or removal rate. In extreme cases, the decline in the polish or removal rate results in an incomplete removal of material, leading to degradation in polishing uniformity. Polishing uniformity is further degraded due to particles being embedded on the pad in a non-uniform fashion. For example, a particular area of the pad may have more particles embedded therein than other areas. This non-uniformity is further accentuated when the wafer surface contains areas of different material, that are removed or polished at different rates.
The embedded particles also reduce the pad useful life, thus requiring frequent changing of the polishing pads. In addition to the cost of the pads, replacing the pads interrupts the wafer manufacturing process and reduces efficiency and yield. Moreover, this necessitates conditioning the pads prior to use, e.g., by planarizing the pads prior to use.
To prevent particles from being embedded in the polishing pad, an ultrasonic transducer has been placed in the slurry to vibrate or agitate the slurry. The ultrasonic transducer is either suspended in the slurry, or rests on the polishing pad. Alternatively, the ultrasonic transducer has been placed in contact with the wafer being polished, or placed under a platen disk onto which the polishing pad is attached, on a side of the platen that is opposite the pad polishing side. However, conventional devices using an ultrasonic transducer do not provide flexibility in providing directed vibration to specifically desired regions of the pad. This causes regional defects on the polished wafer surface and requires frequent changing of the polishing pad.
In addition to the slurry vibration, a large portion of the CMP device is also vibrated, causing undue wear and noise that degrade performance of the CMP device. This results in slow polishing rates and defective wafer polishing. Accordingly, there is a need for a versatile CMP device that variably controls prevention of particles from being embedding in the polishing pad at specific desired locations, and reduces vibration of portions of the CMP device that are adversely affected by undesired vibration.

Device and method for preventing settlement of particles on a chemical-mechanical polishing pad

International Business Machines Corporation


A roll cover assembly for covering a cargo space of a vehicle includes a cassette housing an extendable/retractable roll cover, a first receptacle adjacent a first side wall of the cargo space and having a channel configured to slidably guide a first end of the cassette during insertion or removal, a second receptacle adjacent a second side wall of the cargo space and having an opening configured to receive a second end of the cassette and permit pivoting of the cassette about the second end during removal of the first end from the first receptacle, a locking mechanism releasably locking the first end of the cassette into the first receptacle, and a release device actuatable to release the locking mechanism by pulling along a line-of-action parallel with a direction in which the first end of the cassette moves during removal from the first receptacle.

A conventional roll cover assembly (often referred to as a tonneau) is retained in place by a stiff lateral spring assembly. Such springs can require significant effort to be applied in order to release the tonneau from the vehicle when not in use. The lateral (cross-vehicle) orientation of the springs mean the user has to overcome the spring force themselves, often at arm's length and with no mechanical assistance being provided by the hardware. In addition to the physical effort required to compress the springs, because of the installed location of the tonneau within the vehicle, the task often requires the user to stretch awkwardly or clamber into the vehicle.
The present disclosure seeks to address these issues.


An energy saving air conditioning system is disclosed which provides different air conditioning modes, including a closed-loop mode, an open-loop mode, and a partial-loop mode, for controlling the environment in a high-density apparatus room. The energy saving air conditioning system uses a cloud operating center to monitor the temperature and the moisture inside and outside the high-density apparatus room. The cloud operating system dynamically selects the air conditioning mode in such a manner that energy can be saved and the environment in the high-density apparatus room can be optimally managed.

Field of Invention
The present invention relates to an air conditioning system and method thereof.
Description of Related Art
With the rapid development of various technologies and the pervasiveness of computer dependency in enterprises, the demand for server systems is rising. Large companies commonly use tens or even hundreds of low-cost servers or blade servers in order to deal with a large amount of data and Internet traffic. A blade server is an entire server designed to fit on a small plug-and-play card or board, in which CPUs (central processing units), RAM (random-access memory) and hard drives are usually included thereon. Several blade servers can be installed in one rack, sharing the same power supplies, monitor, keyboard and other electronic components while offering potentially easier maintenance. Through such a configuration, the blade servers are integrated while enabling users to efficiently and rapidly access them.
With the rapid development of cloud technology, the loading and efficiency requirements of servers are significantly increased, and as a result, the heat generated by a server rack is also increased. A conventional high-density apparatus room typically utilizes a closed-loop system to realize temperature control of the room, regardless of the external temperature or humidity. Such an air conditioning system consumes a huge amount of energy.
For the foregoing reasons, there is a need for realizing air conditioning in high-density apparatus rooms, especially those used for cloud data centers, in an energy-saving manner.

Energy saving air conditioning system and air conditioning method thereof


For recording information at high density even at blue-laser wavelengths, a write-once-read-many optical recording medium includes a first inorganic thin film and at least one of a second inorganic thin film and an organic thin film, in which the first inorganic thin film contains at least “R” and “O,” wherein “R” is at least one selected from Y, Bi, In, Mo, V and lanthanum series elements; and “O” is oxygen atom, and the second inorganic thin film and the organic thin film are capable of suppressing at least one of deformation and breakage of the first inorganic thin film and receiving the change of state of the first inorganic thin film.

1. Field of the Invention
The present invention relates to write-once-read-many (WORM) optical recording media. More specifically, it relates to write-once-read-many optical recording media on which information can be recorded at a high density even at blue-laser wavelengths and to processes for recording and/or reproducing information on the write-once-read-many optical recording media.
2. Description of the Related Art
1. Write-once-read-many Optical Recording Media Sensitive to Blue-laser Wavelengths or Shorter
With an increasing development of blue laser capable of recording of information at a very high density, write-once-read-many optical recording media sensitive to blue-laser wavelengths have been increasingly developed.
In conventional write-once-read-many optical recording media, laser beams are irradiated to a recording layer comprising an organic material to change the refractive index typically due to the decomposition and degeneration of the organic material, and thus recording pits are formed. The optical constant and decomposition behavior of the organic material used in the recording layer play an important role to form satisfactory recording pits.
For use in a recording layer of write-once-read-many optical recording media sensitive to blue-laser wavelengths, an organic material must have suitable optical properties and decomposition behavior with respect to light at blue-laser wavelengths. More specifically, the wavelengths at which recording and reproduction is performed (hereinafter briefly referred to as "recording-reproducing wavelengths") are set at a tail on the longer-wavelength side of a major absorption band to increase the reflectance in unrecorded areas and to increase the change in refractive index caused by the decomposition of the organic material upon irradiation of laser to thereby yield a higher degree of modulation. This is because wavelengths at the tail on the longer-wavelength side of a major absorption band of such an organic material yield an appropriate absorption coefficient and a high refractive index. With reference to FIG. 1, a conventional write-once-read-many optical recording medium using an organic material in its recording layer has recording-reproducing wavelengths in the diagonally shaded area in FIG. 1.
However, no organic material having optical properties with respect to light at blue-laser wavelengths equivalent to those of conventional materials has not yet been found. To produce such an organic material having an absorption band in the vicinity of blue-laser wavelengths, the molecular skeleton must be downsized or the conjugate system must be shortened. However, this invites a decreased absorption coefficient and a decreased refractive index.
More specifically, there are many organic materials having an absorption band in the vicinity of blue-laser wavelengths, but they do not have a sufficiently high refractive index and fail to yield a high degree of modulation.
On conventional write-once-read-many optical recording media, information is recorded by the mechanism of deformation of a substrate as well as by change in refractive index due to decomposition and deformation of the organic material. For example, FIG. 3 illustrates a recorded area 101 on a substrate of a commercially available DVD-R medium observed by an atomic force microscope (AFM), showing that the substrate 105 deforms toward the reflective layer 103, which deformation leads to modulation Examples of organic materials sensitive to blue-laser wavelengths can be found in Japanese Patent Application Laid-Open (JP-A) No. 2001-181524, No. 2001-158865, No. 2000-343824, No. 2000-343825, and No. 2000-335110.
However, these publications only teach the spectra of a solution of an organic material and a thin film prepared therefrom in their examples and fail to teach recording and/or reproducing information using the materials.
JP-A No. 11-221964, No. 11-334206, and No. 2000-43423 mention recording using an organic material in their examples but information is recorded at a wavelength of 488 nm. They only describe that satisfactory recording pits are-formed and fail to teach the recording conditions and recording densities.
JP-A No. 11-58955 mention recording using an organic material in the examples but information is recorded at a wavelength of 430 nm. It only describes that a satisfactory degree of modulation is obtained and fails to teach the recording conditions and recording densities.
JP-A No. 2001-39034, No. 2000-149320, No. 2000-113504, No. 2000-108513, No. 2000-222772, No. 2000-218940, No. 2000-222771, No. 2000-158818, No. 2000-280621, and No. 2000-280620 mention recording using an organic material at a wavelength of 430 nm and a numerical aperture NA of 0.65. However, the information is recorded at a low recording density in terms of a minimum pit of 0.4 μm, equivalent to that in DVD media.
JP-A No. 2001-146074 describes recording and/or reproducing at a wavelength of 405 to 408 nm but fails to teach a specific recording density. The recording herein is performed at a low density in which 14T-FEM signals are recorded.
The optical constants of the organic materials disclosed in the above publications at wavelengths around 405 nm, which is the center emitting wavelength of blue semiconductor laser now in practical use, are not equivalent to the required optical constant for recording layers of conventional write-once-read-many optical recording media. The publications fail to disclose examples in which information is recorded at a wavelength around 405 nm at a recording density higher than that in DVD media under specific conditions and fail to teach whether or not information can be recorded at a high density of 15 to 25 GB. In addition, most of the examples in the publications are performed using media of conventional configuration comprising a substrate, an organic material layer and a reflective layer, and colorants to be used therein must have optical properties and functions the same as conventional equivalents.
Such conventional write-once-read-many optical recording media can use only organic materials having a high refractive index and a relatively low absorption coefficient of about 0.05 to about 0.10 for ensuring a satisfactorily high degree of modulation and reflectance.
These conventional write-once-read-many optical recording media using organic materials have a major absorption band in the vicinity of the recording-reproducing wavelengths, thereby have a significantly varying optical constant depending on the wavelength, namely, show a large dependency on wavelength of the optical constant as shown in FIG. 2. They significantly change their recording properties such as recording sensitivity, degree of modulation, jitter and error rate as well as reflectance with varying recording-reproducing wavelengths due to individual difference of the laser or a varying environmental temperature.
The organic materials have insufficient absorptivity to the recording light, the thickness of the resulting organic layer cannot be reduced so much, and a substrate having deep grooves must be used. In this connection, a layer of an organic material is generally formed by spin coating, and such deep grooves are filled with the organic material to form a thick layer of the organic material. Such a substrate having deep grooves is difficult to prepare, and the resulting optical recording medium may have deteriorated quality.
In addition, such a large thickness of the organic material layer leads to a narrow recording power margin and other margins in recording-reproducing properties.
Examples of techniques on layer configurations and recording processes different from those of conventional CD media and DVD media can be found as follows.
JP-A No. 07-304258 discloses a technique for recording information on a medium comprising a substrate, a layer containing a saturable absorption colorant and a reflective layer in this order based on the change of the extinction coefficient (the "absorption coefficient" as used in the present invention) of the saturable absorption colorant.
JP-A No. 08-83439 discloses a technique for recording information on a medium comprising a substrate, a metal deposition layer, a light-absorptive layer and a protective sheet arranged in this order based on the discoloration or deformation of the metal deposition layer by action of heat generated from the light-absorptive layer.
JP-A No. 08-138245 discloses a technique for recording information on a medium comprising a substrate, a dielectric layer, a recording layer containing a photoabsorption material, and a reflective layer arranged in this order by changing the thickness of the recording layer to thereby change the thickness of the grooves.
JP-A No. 08-297838 discloses a technique for recording information on a medium comprising a substrate, a recording layer containing a photoabsorption material and a metal reflective layer arranged in this order by changing the thickness of the recording layer by a factor of 10 percent to 30 percent.
JP-A No. 09-198714 discloses a technique for recording information on a medium comprising a substrate, a recording layer containing an organic colorant, a metal reflective layer and a protective layer arranged in this order by increasing the groove width of the substrate broader than an unrecorded area by a factor of 20 percent to 40 percent.
Japanese Patent (JP-B) No. 2506374 discloses a technique for recording information on a medium comprising a substrate, an interlayer, and a metal thin film arranged in this order by deforming the metal thin layer to thereby form bubbles.
JP-B No. 2591939 discloses a technique for recording information on a medium comprising a substrate, a light-absorptive layer, an auxiliary recording layer and an optical reflective layer by deforming the auxiliary recording layer to a concave shape and deforming the optical reflective layer to a concave shape along the deformation of the auxiliary recording layer.
JP-B No. 2591940 discloses a technique for recording information on a medium comprising a substrate, a light-absorptive layer, a porous auxiliary recording layer and an optical reflective layer or comprising a substrate, a porous auxiliary recording layer, a light-absorptive layer and a reflective layer by deforming the auxiliary recording layer to a concave shape and deforming the reflective layer to a concave shape along the deformation of the auxiliary recording layer.
JP-B No. 2591941 discloses a technique for recording information on a medium comprising a substrate, a porous light-absorptive layer, and a reflective layer arranged in this order by deforming the light-absorptive layer to a concave shape and deforming the reflective layer to a concave shape along the deformation of the auxiliary recording layer.
JP-B No. 2982925 discloses a technique for recording information on a medium comprising a substrate, a recording layer containing an organic colorant and an auxiliary recording layer arranged in this order by allowing the auxiliary recording layer to mix with the organic colorant to thereby shift the absorption spectrum of the organic colorant to a shorter wavelength.
JP-A No. 09-265660 discloses a technique for recording information on a medium comprising a substrate, a multi-function layer having functions as a reflective layer and a recording layer, and a protective layer arranged in this order by forming a bump between the substrate and the multi-function layer. The publication specifies metals such as nickel, chromium and titanium and alloys of these metals as the material for the multi-function layer.
JP-A No. 10-134415 discloses a technique for recording information on a medium comprising a substrate, a metal thin layer, a deformable buffer layer, a reflective layer and a protective layer arranged in this order by deforming the substrate and the metal thin layer and reducing the thickness of the buffer layer in the deformed portion. The publication specifies metals such as nickel, chromium and titanium and alloys of these metals as the material for the metal thin layer and describes that a resin which is deformable and has an appropriate flowability is used in the buffer layer, which buffer layer may further comprise a colorant to accelerate the deformation.
JP-A No. 11-306591 discloses a technique for recording information on a medium comprising a substrate, a metal thin layer, a buffer layer and a reflective layer arranged in this order by deforming the substrate and the metal thin layer and changing the thickness and optical constant of the buffer layer in the deformed portion. The publication describes that a metal such as nickel, chromium or titanium or an alloy thereof is preferably used in the metal thin layer and that the buffer layer comprises a mixture of a colorant and an organic polymer, which colorant has a large absorption band in the vicinity of the recording-reproducing wavelengths.
JP-A No. 10-124926 discloses a technique for recording information on a medium comprising a substrate, a metal recording layer, a buffer layer and a reflective layer arranged in this order by deforming the substrate and the metal recording layer and changing the thickness and optical constant of the buffer layer in the deformed portion. The publication describes that a metal such as nickel, chromium or titanium or an alloy thereof is preferably used in the metal recording layer and that the buffer layer comprises a mixture of a colorant and a resin, which colorant has a great absorption band in the vicinity of the recording-reproducing wavelengths.
These conventional techniques do not intend to provide optical recording media sensitive to blue-laser wavelengths and do not teach layer configurations and recording processes usable at blue-laser wavelengths. In addition, according to the conventional techniques, the colorant in the recording layer must be capable of absorbing light and must have a major absorption band in the vicinity of the recording-reproducing wavelengths, thus the types of colorants to be used are severely restricted.
Most of the conventional techniques record information typically by mechanism of deformation. If information is recorded mainly by mechanism of deformation, the interference among recording marks increases and thereby margins in recording and/or reproducing properties decrease, even though a satisfactory low jitter and a high degree of modulation are obtained.
As a write-once-read-many optical recording medium according to "diffusion system", for example, TDK Corporation has announced a medium having a configuration of a substrate, ZnS—SiO2, Si, Cu, ZnS—SiO2 and Ag arranged in this order in CEATEC JAPAN 2003. The company has reported that the write-once-read-many optical recording medium has a degree of modulation of 65%, a jitter of 6% and a reflectance of 14%. An additional test made by the present inventors has revealed that when Si and Cu are arranged in adjacent layers, they gradually diffuse into another layer during storage and the recording medium shows deteriorated properties. This is a disadvantage of a medium in which components of two layers diffuse into and mix with each other. The medium requires two layers of a dielectric layer comprising ZnS—SiO2 to yield a satisfactorily high degree of modulation and requires many processes and high cost.
Thus, these conventional technologies are insufficient to provide write-once-read-many optical recording media sensitive to blue-laser wavelengths and do not teach layer configurations and recording processes usable at blue-laser wavelengths.
2. Multi-level Recordable Write-once-read-many Optical Recording Media
To increase the recording capacity, multi-level recording techniques have been developed. Recent home users generally treat large-capacity audio data and image-motion picture data, and the capacity of hard disks have increased. However, current CD or DVD optical recording media cannot provide sufficiently high recording capacities.
Under these circumstances, the ML (trademark; Multi Level) Technology has been proposed by Calimetrics, Inc. (CA) as a recording technique to increase conventional optical recording media. In short, the recording linear density is increased according to the ML Technology.
In the conventional CD or DVD optical recording media, the position or length of each recording mark edge varies corresponding to a target data message in recording, and the length of the recording mark is determined in reproduction (slice system). The current slice system will be illustrated in short below.
With reference to FIG. 4, a recording mark row (c) is initially formed on an optical recording medium using a recording waveform (b) corresponding to a target recording data (a).
Reproducing light is applied to the recording mark row (c) recorded on the optical recording medium to reproduce the information to thereby yield a reproducing signal waveform (d).
The reproducing signal waveform (d) is a dull waveform different from the recording waveform (b), a rectangular pulse, and is thereby formatted using an equalizer to yield an equalized waveform (e). More specifically, high-frequency components of the reproducing signal are amplified.
Next, the point of intersection of the equalized waveform (e) and the threshold is detected. A binary data (f) is then outputted as one (1) when the point of intersection is detected within the window and as zero (0) when it is not detected. The binary data (f) obtained by the detection of point of intersection is converted according to a non-return-to-zero (NRZ) procedure to thereby yield a decoded data (g).
In contrast, according to the multi-level recording, a mark having a reflectance at multiple levels is recorded in a fixed-length area "cell", and the information is indicated by the multi-level reflectance. More specifically, one bit is indicated by the presence or absence of a recording mark in the conventional CD or DVD optical recording media. In contrast, recording marks are recorded at, for example, eight different levels of size and is read out as reflectance at eight different levels (FIG. 5). One recording mark indicates information corresponding to three bits, and the recording density can thereby be increased. Here, bidirectional arrow 107 indicates the size of each cell.
In the multi-level recording, the beam spot diameter of laser light in reproduction is generally larger than the cell length, and one recording mark indicates information corresponding to three bits. Thus, the recording linear density can be increased to thereby increase the recording capacity without narrowing the track pitch.
Examples of such multi-level recordable write-once-read-many optical recording media can be found in JP-A No. 2001-184647, No. 2002-25114, No. 2002-83445, No. 2002-334438, No. 2002-352428, No. 2002-352429 and No. 2002-367182. JP-A No. 2001-184647 discloses a concept of multi-level recording on an optical recording medium having a recording layer comprising an organic colorant and a concept of multi-level recording on the optical recording medium in a depth direction of the recording layer. However, this technique intends to provide a multi-level recordable write-once-read-many optical recording medium sensitive to red laser wavelengths, whose layer configuration and organic colorant used are the same as those of conventional CD or DVD write-once-read-many optical recording media.
Aforementioned JP-A No. 2002-25114 discloses a multi-level recordable optical recording medium including a substrate and a recording layer of an organic colorant, which substrate has a specific glass transition point, reflectance and thermal conductivity.
Aforementioned JP-A No. 2002-83445 discloses a multi-level recordable optical recording medium including a recording layer comprising an organic colorant, which organic colorant has specific thermal decomposition properties.
Aforementioned JP-A No. 2002-334438 and No. 2002-352428 each disclose a multi-level recordable optical recording medium having a recording layer comprising phthalocyanine or cyanine colorant, in which the relationships among the wavelength, numeral aperture NA and groove width are specified.
Aforementioned JP-A No. 2002-352429 discloses a multi-level recordable optical recording medium having a recording layer comprising an organic colorant, in which the relationship between the thickness of the recording layer on a groove and the groove depth is specified.
Aforementioned JP-A No. 2002-367182 discloses a multi-level recordable optical recording medium having a recording layer comprising an organic colorant, in which the reflectance in an unrecorded area is specified within a range of 40% to 80%.
To record information at a higher density, the cell length in the multi-level recording must be reduced to the same level as the minimum mark length in the conventional binary recording. Namely, the minimum mark in the multi-level recording is much shorter (smaller) than the minimum mark in the binary recording.
If multi-level recording can be performed at a sufficiently high density using a conventional recording material with a conventional layer configuration, this means that the minimum mark would be shortened even using the conventional recording material with a conventional layer configuration and means that the minimum mark length could be reduced in the binary recording and information could be recorded at a higher density. However, the recording density in the conventional binary recording technique cannot be actually increased unless a special recording-reproducing system is employed.
To provide multi-level recordable write-once-read-many optical recording media which are recordable at a higher density than conventional equivalents according to the binary recording, novel recording materials and layer configuration must be developed.
However, the aforementioned conventional technologies employ conventional recording materials and layer configurations in multi-level recording, although some of conditions such as the thickness of the recording layer and the material of the reflective layer are slightly modified. They cannot form shorter recording marks than conventional equivalents and cannot record and reproduce recording marks much smaller than conventional equivalents with a higher reliability. In short, they only achieve the reproduction of a somewhat smaller recording mark with good reliability by action of the recording and reproducing techniques, and simply apply the recording and reproducing techniques to write-once-read-many optical recording media.
In addition, the conventional techniques form recording marks typically by means of deformation (FIG. 3). The deformation presents no problem when the pitch between recording marks is sufficiently long, i.e., the recording linear density is low, or when the length of a cell in which a multi-level record is formed is not longer than the beam diameter of the reproducing light. However, the deformations interfere with each other and the interference becomes nonlinear when the recording linear density is high or when the length of a cell in which a multi-level record is formed is longer than the beam diameter of the reproducing light.
The phrase "the interference is linear" means that the deformation as a result of interference has a shape substantially indicated by the sum of the deformation in a cell and the deformation of an adjacent cell. FIGS. 6A, 6B and 6C are a plan view, a sectional view, and a sectional view as a sum, respectively of three recording marks which are formed in successive three cells mainly by means of deformation without interference.
FIGS. 7O, 7A, 7B, 7C, 7D and 7E schematically illustrate a reproducing signal which varies depending on the difference of interference among the deformations in three cells. In this case, three recording marks are formed in successive three cells mainly by means of deformation and the total length of the three recorded cells is smaller than the diameter 109 of reproducing beam. If the interference in deformation is linear, the resulting deformation is as shown in FIG. 7B. However, if the interference in deformation is not linear, the resulting deformation is modified as shown in FIG. 7C or FIG. 7D.
The interfered deformation has a length smaller than the diameter 109 of reproducing beam, and the difference in the deformation is therefore not detected. Accordingly, a reproducing signal as shown in FIG. 7E can be substantially obtained even when the deformation varies as shown in FIGS. 7B, 7C and 7D.
Exact data can therefore be decoded by detecting the reflection levels at sampling times T1, T2 and T3 shown in FIG. 7E.
FIGS. 8O, 8A, 8B, 8C, 8D, 8E, 8F and 8G schematically illustrate the relationship between the interference in deformation and the reproducing signal when successive seven recording marks mainly based on deformation are formed in successive seven cells and the total length of the cells is larger than the diameter 109 of reproducing beam.
The interference in deformation in this case becomes more nonlinear than the case shown in FIGS. 7B, 7C and 7D, and the interfered deformation is as shown in FIGS. 8B, 8C and 8D when simply illustrated. The interfered deformations each have a length larger than the diameter 109 of reproducing beam, and the difference among the deformations can be clearly detected. Thus, reproducing signals shown in FIGS. 8E, 8F and 8G are obtained from the deformations in FIGS. 8B, 8C and 8D, respectively.
Accordingly, when reflection levels are detected at sampling times T1 through T7 shown in FIGS. 8E, 8F and 8G, different data corresponding to the different deformations are decoded, thus failing to decode the exact data.
As is described above, recording of data mainly based on deformation leads to different interference behaviors among recording marks depending on recording patters, and the resulting reproducing signals cannot be predicted. Thus, the data are not recorded and/or reproduced properly at a higher density.
3. Recording-reproducing Technique Using PRML System
As another possible solution to achieve high-density recording than the ML recording technique, the application of partial response and maximum likelihood (PRML) technique to optical recording media has been studied.
With an increasing recording linear density to achieve high-density recording, the reproducing signal has a dull waveform. In other words, with reference to FIG. 4, the reproducing signal waveform (d) is not a rectangular waveform as in the recording waveform (b). The high frequency components of the reproducing signal are amplified using an equalizer and the reproducing signal is converted to have an equalized waveform. When the reproducing signal has a dull waveform with an increasing density, a larger quantity of high frequency components must be amplified. In amplification of the high frequency components, signal degrading components are also amplified by the equalizer, thus inviting significantly decreased signal-to-noise ratio (SNR) of the reproducing signal. PRML is a reproducing signal processing system to prevent SNR of the reproducing signal from decreasing even in high density recording.
The PRML system will be briefly illustrated below.
FIG. 9 illustrates a recording data (a) as target information, a recording waveform (b), a recording mark row (c), a reproducing signal waveform (d) and equalized waveforms (e), (f) and (g).
More specifically, the equalized waveforms (e), (f) and (g) are obtained as a result of equalization of the reproducing waveform (d) by an equalizer depending on PR(1,1) characteristic, PR(1,2,1) characteristic and PR(1,2,2,1) characteristic, respectively. The PR(1,1) characteristic is a characteristic in which an impulse response appears at the rate of 1:1 at two successive identification points. The PR(1,2,1) characteristic is a characteristic in which an impulse response appears at the rate of 1:2:1 at three successive identification points. The PR(1,2,2,1) characteristic is a characteristic in which an impulse response appears at the rate of 1:2:2:1 at four successive identification points. The equalized waveforms (e), (f) and (g) in FIG. 9 show that an equalized waveform becomes duller with an increasing complexity of the PR characteristic.
In the PRML system, an increase in the signal degrading component in the equalizer can be suppressed by equalizing the reproduced waveform into a waveform of a PR characteristic which is closer to the characteristic of the reproduced waveform.
In the reproduction signal processing of PRML system, a Viterbi decoder which is a representative one of maximum likelihood decoders is generally used as a most-likelihood decoder in decoding of the equalized waveform signals. For example, if the reproduced waveform is equalized into a waveform of the PR(1,2,1) characteristic by the equalizer, the Viterbi decoder selects a series having the smallest error with respect to the sample series of the equalized waveform from all of the reproduced waveform series which satisfy the PR(1,2,1) characteristic and estimates and outputs recording data (binary data, decoded data) used as a source for generating the selected reproduced waveform series.
Thus, the PRML system realizes high-density recording even using a conventional optical system. However, even the PRML system cannot record and reproduce information with high reliability when the interference among recording marks (intersymbol interference) becomes large and becomes nonlinear, namely, when a predictable interference among recording marks occurs. In other word, the PRML system can be applied onto to such a case in which a predictable interference among recording marks occurs. If an interference among recording marks different from the predicted one occurs, the advantages of the PRML system are not obtained.
The deformation of recording marks must be prevented to suppress the interference among recording marks at a predictable level.
By providing write-once-read-many optical recording media on which information can be recorded by multi-level recording at a wavelength of blue-laser wavelengths or shorter, recording marks with higher quality than those obtained by the conventional binary recording technique can be formed. Information can be recorded on the resulting write-once-read-many optical recording media by the conventional binary recording technique at a wavelength of blue-laser wavelengths or shorter and also by multi-level recording at a higher density by the application of the PRML system. Requirements to achieve write-once-read-many optical recording media sensitive to blue-laser wavelengths or shorter wavelengths can be considered as requirements to provide write-once-read-many optical recording media that allow multi-level recording at a wavelength of blue-laser wavelengths or shorter.
The requirements to write-once-read-many optical recording media that allow multi-level recording at a wavelength of blue-laser wavelengths or shorter are the following requirements (1), (2) and (3):    (1) smaller recording marks;    (2) less interference among recording marks; and    (3) higher stability of recording marks.
In most of the conventional write-once-read-many optical recording media, information is recorded mainly based on deformation as described above.
In binary recording, the minimum mark has a sufficient size with respect to the diameter of reproducing beam (approximately half the diameter of reproducing beam), the amplitude derived from the minimum mark is sufficiently large, and the deformation in the minimum mark is large.
In contrast, in multi-level recording, the minimum mark has an insufficient size with respect to the diameter of reproducing beam, and the amplitude derived from the minimum mark in multi-level recording is approximately one-half to one-tenths or less the amplitude derived from the minimum mark in binary recording, and the deformation in the minimum mark is very small.
Conventional CD or DVD write-once-read-many optical recording media have a layer of an organic colorant having optical absorptivity arranged directly adjacent to a substrate. Thus, the substrate deforms to a large extent. The degree of modulation is primarily affected by the deformation of substrate and is secondarily affected by the decomposition of the organic colorant. A deformation of the substrate within an elastic deformation region may be relieved, for example, by extraneous heat. A deformation of the substrate exceeding the elastic deformation region is limited, but its shape may significantly vary with the heat applied upon the formation of an adjacent recording mark or with the deformation of the adjacent recording mark.
FIGS. 10 and 11 illustrate these phenomena.
FIG. 10 shows recording marks in a write-once-read-many optical recording medium having a conventional structure of a substrate, a colorant layer, an Ag reflective layer and a protective layer arranged in this order.
FIG. 10 illustrates a waveform A of a reproducing signal; an atomic force micrographic (AFM) image B of the surface of the substrate after removing the protective layer, Ag reflective layer and colorant layer; and a deformation C of the cross section of the substrate as determined based on the AFM image B. FIG. 10 shows that the recorded area is much largely deformed with a concave shape at a center part of the recording mark. The interference in deformation (interference within one recording mark) is nonlinear, as illustrated in FIGS. 7C, 7D, 8C and 8D.
FIG. 11 illustrates recording marks obtained by recording the information as in FIG. 10 on the conventional write-once-read-many optical recording medium and applying a weak direct-current light of about one-fifths of the recording power to the medium.
FIG. 11 illustrates a waveform A of a reproducing signal; an atomic force micrographic (AFM) image B of the surface of the substrate after removing the protective layer, Ag reflective layer and colorant layer; and a deformation C of the cross section of the substrate as determined based on the AFM image B. FIG. 11 shows that the deformation of substrate changes and thus the waveform of the reproducing signal changes upon irradiation of the weak direct-current light. This is probably because the application of the weak direct-current light relieves the strain in the deformed portion of the substrate.
The fact that the shape of deformed portion of the substrate varies upon irradiation of such a weak direct-current light shows that the colorant layer on the recording mark should have a sufficient optical absorptivity and that the conventional write-once-read-many optical recording medium generates the degree of modulation mainly based on deformation.
Recording mainly based on deformation invites the following problems:    (1) the interference in deformation within one recording mark increases, and the waveform of the reproducing signal varies depending on the deformation, i.e., depending on the recording mark length;    (2) the interference in deformation among recording marks increases, and the waveform of the reproducing signal varies depending on the deformation, i.e., depending on the recording pattern such as the types of recording marks between anterior and posterior tracks or between adjacent tracks; and    (3) the deformation is relieved in reproduction, in recording onto an adjacent track, in leaving at high temperatures or in leaving for a long period of time, and the waveform of the reproducing signal varies.
These problems invite the following disadvantages:    (a) deteriorated jitter, error rate and other properties;    (b) narrowed recording power margins in jitter, error rate and other properties;    (c) unreasonable asymmetry largely shifted from zero under recording conditions to yield the optimum jitter or minimum error rate;    (d) unstable formation of small recording marks; and    (e) unpredictable interference among recording marks.
These disadvantages and problems also occur in conventional binary recording but are significant in write-once-read-many optical recording media for recording at a higher density, i.e., write-once-read-many optical recording media corresponding to the multi-level recording and/or PRML system.
In addition, the conventional write-once-read-many optical recording media each having a recording layer comprising an organic material have the following disadvantages (i), (ii), (iii) and (iv):    (i) very narrow or small degree of freedom in selection of the organic material;    (ii) very large dependency on wavelength;    (iii) deep grooves of the substrate for satisfactory recording-reproducing properties; and    (iv) no recording in "lands" between grooves.

This patent is subject to a terminal disclaimer.

Write-once-read-many optical recording media and process for recording and reproducing information on the media


An active temperature controlled container is configured to be portable so as to safely transport temperature sensitive and perishable goods (such as biological material): within a vessel that is thermally coupled to a thermoelectric assembly disposed within the container, where the thermal engine is powered by a power source, such as a battery. The thermoelectric assembly may include one or more resistors coupled to a resistor spacer block to act as a cool sink by actively and passively increasing the efficiency of the thermoelectric assembly.

Active temperature controlled containers can comprise a number of thermocouples to actively apply the Peltier effect to advantageously transport heat within an iso-thermal transport system. The Peltier effect is the presence of heating or cooling at an electrified junction of two different conductors. The Peltier effect has been advantageously used in harnessing thermoelectric effects whereby temperature differences are directly converted to electric voltages, and vice versa. Accordingly, a thermoelectric heat pump is built to include a plurality of thermocouples that include a junction of two different conductors that are electrified at the junction to create heating or cooling, according to the temperature sensitive cargo disposed within the iso-thermal transport and storage system. Examples of temperature sensitive cargo that can benefit from transport in iso-thermoelectric heat pump and storage systems include biological materials and samples, including cell and tissue cultures, nucleic acids, bodily fluids, tissues, organs, embryos, plant tissues, and other sensitive goods such as pharmaceuticals, vaccines and chemicals. Various systems for temperature regulation for transported materials requiring a stable thermal environment are known. Iso-thermal transport systems seek to be robust, efficient, and self-sufficient for safely storing and maintaining cargo during transport, storage, or both.
Improved active temperature controlled containers are needed to allow for improved cool sinks that can increase the temperature of temperature sensitive cargo with respect to the ambient temperature. Improved cool sinks can enhance the operation and transportability of active temperature controlled containers.

Portable active temperature controlled container comprising a cool sink

Ambassador Asset Management Limited Partnership


Disclosed herein are structures for supporting a clamshell- or slider-type portable electronic device such as a notebook computer; personal digital assistant; or wireless telephone. The clamshell- and slider-type portable electronic devices typically have at least two assemblies—a first housing assembly, and a second housing assembly containing at least a keyboard. In a clamshell-type electronic device, the first housing assembly and second housing assembly are connected by a hinge and pivot between at least an open position and a closed position. In a slider-type electronic device, the first housing assembly and second housing assembly are connected by a slide connection and slide between at least an open position and a closed position. In portable electronic devices made in accordance with the invention, the keyboard is comprised of a first set of keys and a second set of keys. The keys comprising the first and second sets have touch surfaces configured to receive keystrokes. The touch surfaces of the first set of keys extend above the touch surfaces of the second set of keys. When a portable electronic device having either the clamshell- or slider-type configuration is in a closed position, the combination of the varying heights of the touch surfaces of the keys and cooperating structures in the first and second housings hinders relative movement between the first and second housing assemblies when an external force (for example, due to an accidental drop) is applied to the portable electronic device. The hindering of relative movement helps to protect the portable electronic device from damage.

Portable electronic devices (for example, notebook computers; personal digital assistants; handheld computers; cellular telephones; etc.) often have clamshell- or slider-type configurations. In a clamshell configuration, two halves comprising the portable electronic device are joined by a hinge on a common side. The two halves are configured to pivot about the hinge during opening and closing operations. The clamshell configuration has advantages. In particular, when a portable electronic device having a clamshell configuration is closed, the display and keyboard are hidden from view and protected by the housing.
This is in contrast to a so-called "monoblock" (candybar) configuration where the display and keyboard are mounted in a unitary housing and exposed at all times. In such a configuration the display is vulnerable to scratching, and the keyboard vulnerable to contamination by, for example, liquids.
In a portable electronic device having a slider configuration, the two halves comprising the device are connected by a slider connection that permits relative movement between the halves from an open position to a closed position. In a slider-type portable electronic device, the display is typically exposed at all times, and the keyboard is hidden from view when the device is in the closed position. Such a configuration protects the keyboard from damage when the portable electronic device is not in use.
Conventional portable electronic devices having clamshell- and slider-type configurations have been found in some instances to be susceptible to damage when dropped. Often, dropping the portable electronic devices causes bending or twisting of one or both of the halves comprising the portable electronic device. The bending or twisting can be particularly harmful to fragile electronic parts comprising the portable electronic devices such as, for example, the display.
Accordingly, those skilled in the art seek improved structures for supporting a clamshell- or slider-type portable electronic device, particularly structures that significantly reduce the risk of damage to the device when the device is dropped, or exposed to other accident situations where external forces are applied to the device.

Support structure for portable electronic device


A method is used to calibrate a light unit, including at least one light source, the light unit being part of a medical imaging apparatus. In an embodiment, the method includes positioning a calibration phantom at a calibration position, in particular a first calibration position; arranging the light source so that its beam illuminates the photodetector at least partially; starting or continuing the recording of light intensities using the photodetector; modulating the signal of the light source at least once; rotating the light beam around a given rotation axis while recording the rotational position; synchronizing the time values of the rotational position of the light beam and the acquired signal intensities using the modulation of the light signal; and mapping the rotational position, in particular the rotation angle, of the light beam to a spatial position using the light intensities recorded by the photodetector.

It is known to use medical imaging apparatus to guide interventions. This is called interventional radiology.
Additionally, it is known to use laser guidance to support medical personnel e.g. by positioning a needle at a certain position and angle into the body of a patient.
Both techniques may be combined using a laser unit or generally a light unit positioned on a medical imaging system.
This light unit is used to mark the desired position and angle on the body surface of the patient.
From US 2009/0234370 A1, a computed tomography apparatus is known that has two fan lasers with which a guideline for a medical instrument can be marked. The fan lasers are arranged so as to be adjustable on the gantry of the computed tomography apparatus in order to be able to identify different planes in space or to mark different guidelines in space.
The adjustment of the laser beams is organized by markers positioned at predetermined positions.
US 2012/0220863 A1 shows a computed tomography apparatus again having two fan lasers. The fan-shaped light beams are reflected at mirrors, the mirrors being rotatable around a mirror rotation axis. This extends the positions where planes in space can be marked.
To calibrate the light units, it is also known to use calibration phantoms. These phantoms contain photodiodes to detect the projected light beams. The calibration phantoms are usually pluggable and only connected during the calibration process.
To connect the data recorded by the calibration phantom and the light unit during the calibration process a synchronization of the timing of the devices is necessary. The absolute time is not necessary for calibration purposes. Only the past time after a starting time tO is needed to connect the data.

Method to calibrate a light unit, storage medium, aperture plate and medical imaging apparatus


A motion detecting and alerting system includes at least two motion detectors adapted to detect motion and transmit transmission signals upon detecting motion, at least one alert module adapted to receive the transmission signals and indicate the motion and a wrist strap carried by the alert module.

Hunting is a sport which has been popular among lovers of the outdoors since man has appeared on the Earth. Various approaches to hunting game such as deer have been devised in such a manner as to maximize the chances of sighting and killing the game. A common approach to hunting game involves a hunter's sitting in an elevated stand and listening and watching the woods or fields beneath the stand for signs of an approaching deer or other game animal. In the event that the hunter spots a game animal which is deemed to be within firing range, the hunter fires upon the animal in attempt to kill the animal. If the animal is struck, the hunter climbs down from the stand and walks over to the animal to ascertain whether the animal was killed by the shot. In the event that the initial shot failed to kill the animal, the hunter may fire additional shots at the animal. In either case, the killed animal is then typically transported to a camp or other area on an all-terrain vehicle (ATV) or the like and dressed and preserved for consumption.
Hunting game from an elevated stand has a number of drawbacks. It may be difficult for a hunter to quickly locate a stand and then climb up into the stand while carrying a firearm and other equipment. In cold weather climates, bulky clothing and inclement weather conditions such as rain, snow, ice and freezing temperatures may increase the dangers of climbing into a stand. It may also be difficult for a hunter to discern the signs of a game animal approaching the stand since the deer may be obscured by heavy woods or other foliage or structures.
Another drawback to using a stand to locate game is that the hunter is confined to a small area in the stand and cannot freely move about to search for game. Thus, considerable patience may be required for a hunter to wait for the game to approach the stand. Moreover, as long as he or she remains in the stand, the hunter is not able to investigate other areas for the presence of game and thereby increase his or her chances of success.
Therefore, a motion detecting and alerting system and method which is particularly suitable for hunting applications and can detect motion of a game animal at one or multiple locations and alert a mobile hunter to the motion is needed.

Motion detecting and alerting system and method


A bench-test method which correlates well with other more costly engine test methods, and which can be used to screen oleaginous formulation prior to performing expensive engine tests. The method comprises a) contacting ball bearing(s) having a smooth surface area with an oleaginous fluid to be screened; b) treating the oleaginous fluid during contacting with corrosive vapor for a period of time and at a temperature sufficient to form a metal oxide coating on the ball bearing(s) surface; and c) visually rating the metal oxide coating on the ball bearings.

This invention relates to a bench test method for oleaginous fluids. More specifically, this invention provides a reliable bench test method for screening oleaginous fluid compositions and lubricant formulations for their ability to inhibit engine rust formation prior to more extensive engine testing.
Until now, the oil and automotive industry has relied on a number of standardized engine tests to determine the beneficial or detrimental effects of additives in various oleaginous fluid compositions, specifically for determination of the ability of oleaginous formulations to inhibit engine rust. Numerous engine tests are usually required to qualify a particular oleaginous formulation before it is accepted by the oil and/or automotive industry. Typically, the engine tests are quite expensive and time consuming. One particularly useful engine test is the Sequence IID engine test performed in accordance with ASTM STP 315H Part I. While the IID engine test has been relied on for a number of years, the engines utilized in the test are designed for use with leaded fuels. Such leaded fuel engine designs are obsolete and thus are no longer in production. Current engines are designed to run exclusively on unleaded fuels. Likewise, leaded fuel is becoming less readily available. There is a need therefore for a reliable, yet less costly means for determining how a particular oleaginous formulation will perform in an engine under actual operating conditions.

Bench test method for rating the corrosion inhibiting ability of an oleaginous fluid


A game system has a plurality of slot machines, each slot machine having a controller for executing a basic game, and transmitting a signal for making a transition to the roulette game when a prescribed symbol combination is stopped on a payline; a second game device for executing the roulette game, which is provided as a physically separate device from the slot machines; a display for displaying images according to a game status of the second game device; and a center controller capable of communicating with these devices by being connected with them through a network. If the roulette game is already executed when a signal for requesting a transition to the roulette game is received from a slot machine, the center controller keeps a transition to the roulette game waiting, and controls that slot machine and the second game device to start the roulette game at a timing where a transition to the roulette game becomes possible.

1. Field of the Invention
The present invention relates to a game system including slot machines and a game control method.
2. Description of Related Art
As disclosed in U.S. Pat. No. 6,634,941 and U.S. Patent application publication No. 2004/110558, the conventional slot machine includes a slot machine which executes a free game or a bonus game which has a higher possibility for becoming advantageous to a player than the basic game, in addition to the basic game. The free game or the bonus game is one of the second games. In the second game, a probability for a specific combination associated with a prize becomes high as a special symbol is displayed, or a payout in the case of realizing the specific combination associated with a prize is set to be greater, in the disclosed slot machine, for example. In this way, in the second game, an attractive game different from the basic game is executed, so that the player can have a great expectation to the second game.
In the other disclosed slot machine, a prize value that can be obtained by the player in the second game is displayed to the player prior to the second game, so as to strongly arouse the player's interest.
In such conventional slot machines, some contributions can be made in terms of arousing the player's interest by using the second game, but this is done within the casing of the same slot machine.

Game system including slot machines and game control method thereof


The present invention relates to a content providing system, a receiving apparatus and method, a storage medium, and a program, which enable to perform a variety of contents provisions. An operational terminal 21 can obtain, from a storage terminal 1, contents corresponding to utilization information sent from an operational terminal 11 that is receiving provision of predetermined contents from a storage terminal 1. That is, if a user 23 is interested in contents that a user 13 is watching and listening to on the operational terminal 11, and desires to watch and listen to it, the user 23 can watch and listen to on the operational terminal 21, the contents that the user 13 is watching and listening to, by holding the operational terminal 21 very close to the operational terminal 11, or holding the operational terminal 11 very close to the operational terminal 21.

There have been proposed various types of methods in which an apparatus for providing contents (hereinafter referred to as a content providing apparatus) via an established communication path to an apparatus for utilizing contents (hereinafter referred to as a content utilizing apparatus), or in which a content utilizing apparatus receives the provision of contents from a content providing apparatus.
However, there exists neither a method in which a first content utilizing apparatus obtains from a content providing apparatus contents corresponding to utilization information of contents sent from a second content utilizing apparatus that is receiving provision of predetermined contents from the content providing apparatus, nor a method in which a first content providing apparatus obtains from a second content providing apparatus contents corresponding to provision information of contents sent from the second content providing apparatus that is providing predetermined contents to a content utilizing apparatus, and stores and provides them to the content utilizing apparatus.
While on the side of receiving provision of contents, when receiving contents and displaying the received contents, or registering (storing) the displayed contents, it is usually configured so as to inquire a user about permission thereof. That is, the user is required to answer (for example, to input permission to a displayed dialog) every time such an inquiry is made, and therefore an operation thereof is tedious.

Content providing system, receiving apparatus and method, storage medium, and program for content reception by short range communication enabled devices


Provided is a composition containing a sterol ester, which is an oil poorly soluble in water, and superior in transparency, stability, foaming property, rinsability, skin feel (during rinsing and/or after use), and emollience. A composition containing    (A) a sterol ester,    (B) one or more anionic surfactants selected from (B1) N-acylamino acid having a C8-22 acyl group or a salt thereof, (B2) polyoxyethylene alkyl ether sulfate or a salt thereof,    (C) a betaine-type amphoteric surfactant,    (D) glyceryl mono-C8-14 fatty acid ester,    (E) C5-6 hydroxyalcohol, and    (F) water, and    having pH 4-8.

1. Field of the Invention
The present invention relates to a composition containing (A) a sterol ester, (B) a particular anionic surfactant, (C) a betaine-type amphoteric surfactant, (D) glyceryl mono-C8-14 fatty acid ester, (E) C5-6 hydroxyalcohol and (F) water.
2. Discussion of the Background
Sterol ester is an oil having an emollient effect of "being absorbed well by skin and hair, and conferred smoothness and softness", and addition to liquid cleansers has been desired. Since sterol ester is poorly soluble in water, it is generally provided in the form of an emulsion wherein it is dispersed and stabilized in water. However, a sufficiently stable liquid cleanser cannot be easily obtained.
For example, patent document 1 proposes a technique for stably dispersing an oil phase comprising a liquid crystal in an aqueous phase mainly containing a foaming/cleansing ingredient, and patent document 2 proposes a technique for stabilizing an emulsion of an oily component in an aqueous solution of a foaming/cleansing ingredient. However, these techniques only afford a cloudy composition without transparency, which is less attractive visually for consumers, and its stability is not necessarily satisfactory. In addition, an oil may be solubilized in an aqueous phase by using a solvent such as ethanol. However, use of a volatile solvent causes problems of insufficient stability, low foaming/lathering property, friction during rinsing and insufficient emollient effect due to a decreased residual amount of a sterol ester on the skin or hair. While a nonionic surfactant with high HLB may also be used for solubilizing an oil in an aqueous phase, problems of decreased foaming/lathering property and rinsability and after-use stickiness of the skin or hair occur.

Liquid cleanser comprising sterol ester and C5-6 hydroxyalcohol