A system for starting a gas turbine engine includes an engine controller and a fuel controller. The engine controller varies the engine speed between a minimum start speed and a maximum start speed until light-off of the engine occurs. The fuel controller operates a fuel command to vary fuel provided to a combustion chamber of the engine until light-off of the engine occurs.

The present invention relates generally to gas turbine engines, and in particular to a system and method for starting an auxiliary power unit (APU) at high altitudes.
Starting a gas turbine requires the engine to be motored to a certain speed such that the fuel-air mixture provided to the combustor is conducive to light-off (i.e., successful ignition of the engine). These conditions become much more difficult to achieve when starting the engine at high altitude. For example, if an aircraft is flying at 40,000 feet, there will be very little air flowing through the engine, and the air that is flowing through the engine will be traveling at fairly high velocities. This makes it very difficult to start an APU, or any gas turbine engine at high altitudes.
Traditionally, starting an APU at high altitude involves spooling the engine up to a constant start speed. When the engine is up to speed, a constant amount of fuel is provided to the combustion chamber for lighting. An igniter in the chamber continuously sparks to attempt to light-off the engine. Due to the unstable air conditions at high altitude, this process is very unpredictable and can cause serious delays in startup of the APU. It is desirable to provide a faster, more reliable method of starting a gas turbine engine at high altitude.

High altitude start of a gas turbine engine using fuel pulsing and starter toggling


The invention provides methods, systems, and products for communicating between engine computers without the participation of a flight deck computer. The invention allows the engine computers to coordinate activities for real-time control of the engines for improved efficiency using an existing ARINC 429 communications bus. The invention facilitates cross-engine communications over the same ARINC 429 communications bus used for communicating with the Flight Deck Computer, without installation of a second, dedicated communications bus for cross-engine communications. The invention thus provides a cost effective way to allow the engines to coordinate activities without expensive installation and recertification of airframe modifications.

The present invention generally relates to avionics systems in commercial and military aircraft, and more specifically, to bus communications methods and systems for cooperatively sending information between embedded computers each controlling individual engines within an airframe.
Modern turbine engines are complicated devices requiring computer control to maintain their peak efficiency of operation. Data about their environment must be fed to these turbine engines and their operating parameters must be precisely adjusted in a coordinated manner. A pilot uses flight deck controls, such as throttles, to direct the operation of these turbine engines, and these directions must be communicated to computers associated with the engine to provide a coordinated change of operating variables within permissible envelopes. Modern aircraft employ a flight deck computer to serve as a communications hub for receiving the manual control inputs received from the numerous manual controls in the cockpit, determining which flight instrument is to receive the input, formatting a message with information regarding the manual input, and sending the message to the flight instrument. The engine computers are normally one of many such flight instruments on an aircraft. The engine computers in turn send status and acknowledgement messages back to the flight deck computer for displaying status and values of flight parameters.
The ARINC 429 bus is typically used for such communications. The ARINC 429 protocol was originally promulgated by Aeronautical Radio, Incorporated (ARINC) for airborne data communication between instruments and employs a unidirectional transmission of 32 bit words (messages) over two wire twisted pairs. Each word contains five fields, one of which is a message identifier, or label, identifying the data type and the parameters associated with it.
When two or more engines are carried on the airframe, each engine computer must not only interact with the flight deck computer, but it must also interact with other engine computers. Not only must the operating variables within each engine be coordinated internally, but the changes in one engine must be coordinated with the other engines as well. One problematic scenario is the situation in which one engine goes out and the others must compensate for the change in bleed air requirements and thrust. If the remaining engines are not adjusted, then they may also fail through overheating. Normally the pilot would provide control over the engines but some things may be controlled between the engines without pilot intervention.
One solution for a multi-engine aircraft involves establishing a second cross-engine communication bus dedicated for communications between the engine computers and programming the engine computers to exchange information over the communication bus. This solution allows the engine computers to communicate with each other without involvement from the flight deck computer over the ARINC 429 bus. Without such a dedicated communications bus, the pilot must manually perform the coordination activities between the engines or the coordination task must be accomplished within the flight deck computer. In general, the vendor of the flight deck computer is not necessarily the same as the vendor of the engine computers, and neither party necessarily has the expertise to support the other in this regard.
U.S. Pat. No. 5,165,240 shows a configuration of a full authority digital engine control, or FADEC, serving as an engine computer for each of two engines. The left and right FADECs communicate with each other via a RS-422 bus (36, FIG. 2), and each receives inputs from their respective engine sensors and autopilots (24L, 24R, FIG. 2), and sends display information to a common engine indication emergency crew alerting system (EICAS) (28L, 28R, FIG. 2). A first ARINC 429 communications bus provides communications with the engine sensors, and a second ARINC 429 communications bus, which may be the same as the first ARINC 429 communications bus, also provides communications with the EICAS.
U.S. Pat. No. 5,136,841 describes such an engine-to-engine communication setup, where an optical bus is provided for allowing two engine electronic control units (engine computers) to communicate with one another (FIG. 1), replacing the standard isolation station coupled with each engine electronic control unit to provide electrically isolated engine-to-engine communications. The optical couplers to an optical bus provide the necessary electrical isolation instead of the standard ARINC 429 connection. This configuration implements a special dedicated communications bus (88A, 88B, 90A, 90B) between the two engine control units (12, 14).
However, some business jets do not have existing cross-engine communication buses wired into the aircraft, which prevents engine-to-engine sharing of important data. To retrofit such a cross-engine communication bus into an existing airframe would require major maintenance and incur significant cost in terms of installation, testing, updates of schematic diagrams, new documentation, and recertification of the aircraft. Furthermore, significant aircraft downtime would be required in order to add this ability to an existing aircraft configuration.
As can be seen, there is a need for a method and apparatus to support engine-to-engine communications in an airframe in which there is no dedicated bus installed between engines. Such a capability should be relatively inexpensive and capable of implementation without excessive aircraft downtime.

Cross-engine aircraft communication system


The present invention relates to an isolated protein or polypeptide selectively expressed in chondrocytes in lower proliferative or upper hypertrophic zones of long bone and embryonic vertebrae growth plates as well as to antibodies, fragments, and probes recognizing these proteins or polypeptides. The proteins or polypeptides can be used for treating non-union bone defects. The antibodies, binding portions thereof, and probes can be used to inhibit arthritic progression of articular chondrocytes. The antibodies, binding portions thereof, and probes can also be used to identify the occurrence of chondrocytes proliferation or hypertrophy. The encoding DNA molecule, either alone in isolated form or in an expression system or a host cell, is also disclosed.

Endochondral ossification is remarkably similar in diverse biological settings. The remodeling of calcified cartilage into bone can be found in embryonic sterna, vertebrae, and limbs, juvenile long bone development, fracture healing by callus formation, and ectopic bone formation induced by bone morphogenetic proteins. The same process can also be found in pathologic conditions, such as cartilaginous neoplasms, heterotopic ossification, and degenerating articular cartilage. This commonality suggests that mineralizing chondrocytes are committed to the same innate developmental pathway.
During the process of endochondral ossification, chondrocytes undergo a progression of maturational changes, with marked biochemical and physical changes in both the cells and surrounding matrix. These changes are most evident in the growth plate where they are spatially and temporally ordered (Buckwalter et al., J. Bone and Joint Surg., 68A:243-255 (1986); Gibson et al., Cell Biol., 101:277-284 (1985); and Poole, "Cartilage in Health and Disease", Arthritis and Allied Conditions: A Textbook of Rheumatology, 279-333, (1993)). Resting chondrocytes are flat, irregularly-shaped nondividing cells. As these cells enter the cell cycle, they become arranged in columns and undergo the rapid proliferation necessary for long bone growth. Collagen fibrils in the resting and proliferating region of the growth plate are predominantly type II collagen with associated minor collagens type IX and type XI (Buckwalter Clin. Orthop., 172:207-231 (1983) ("Buckwalter"); Oshima et al., Calcif. Tiss. Int., 45:182-192 (1989) ("Oshima"); Castagnola et al., J. Cell Biol., 102:2310-2317 (1986); Liu et al., Dev. Dynamics, 198:150-157 (1993); and Linsenmyer et al., Development, 111, 191-196 (1991)). The matrix is characterized by an abundance of high molecular weight proteoglycans, which have a structural role in addition to preventing calcification (Buckwalter; Dziewiatkowski et al., Calcif. Tiss. Int., 37:560-567 (1985); Kosher et al., Dev. Biol., 118:112-117 (1986); and Chen et al., Calcif. Tissue Int., 37:395-400 (1985)). In the hypertrophic region of the growth plate, proliferation ceases and a significant increase in cell volume, up to 8-fold, occurs. Hypertrophic chondrocytes form arcades and initiate the synthesis of type X collagen, while collagen types II and IX and proteoglycan content decrease. In the most inferior part of the growth plate, adjacent to the metaphysis, the cartilage mineralizes. Hypertrophic chondrocytes in the calcified tissue may undergo apoptosis (Shapiro et al., J. Bone Min. Res., 10(S1):S238 (1995); Fujita et al., Trans. Ann. Mtg. Othop. Res. Soc., 20:470 (1995); and Farnum et al., Trans. Ann. Mtg. Othop. Res. Soc., 20:77 (1995)), partially convert to an osteoblastic phenotype (Cancedda et al., J. Cell Biol., 117:427-435 (1992)), or remain quiescent until resorption by the invading blood vessels. The signals necessary for calcification are poorly understood, but calcification appears to be effected through the production of matrix vesicles, which contain alkaline phosphatase, phospholipase A.sub.2, NTP-pyrophosphohydrolase, calcium, phosphate, and matrix metalloproteases (Dean et al., Calcif. Tissue Int., 50:342-349 (1992); Lewinson et al., J. Histochem. and Cytochem., 30:261-26 (1982); Wuthier et al., Cal. Tissue Int., 24:163-171 (1977); and Watkins et al., Biochem. Biophys. Acta, 631:289-304 (1980)). The calcified cartilage serves as a scaffold for vascular invasion and deposition of the primary spongiosa.
A variety of cell culture models have been utilized to study the developmental changes associated with endochondral ossification. Embryonic chondrocytes from sterna (Leboy et al., J. Biol. Chem., 264:17281-17286 (1989) ("Leboy"); Sullivan et al., J. Biol. Chem., 269:22500-22506 (1994) ("Sullivan"); and Bohme et al., Exp. Cell Res., 216:191-198 (1995) ("Bohme")), and vertebra (Lian et al., J. Cellular Biochem., 52:206-219 (1993) ("Lian")), limb bud mesenchymal cells in micromass cultures (Roark et al., Develop. Dynam., 200:103-116 (1994) ("Roark") and Downie et al., Dev. Biol., 162:195 (1994) ("Downie")), growth plate chondrocytes in monolayer (Rosselot et al., J. Bone Miner. Res., 9:431-439 (1994) ("Rosselot"); Gelb et al., Endocrinology, 127:1941-1947 (1990) ("Gelb"); and Crabb et al. J. Bone Mineral Res., 5:1105-1112 (1990) ("Crab")), or pellet cultures (Kato et al., Proc. Nat. Acad. Sci., 85:9552-9556 (1988) ("Kato")) have been used to characterize chondrocyte responses to exogenous factors, many of which function in an autocrine manner. From these studies has emerged a critical role for a number of growth factors, including bFGF, TGF.beta., IGF-I, and PTHrP, which are present in the growth plate and regulate chondrocyte proliferation and differentiation. The expression of these factors and their associated receptors are maturation dependent and exquisitely regulated in the growth plate (Bohme, Roark, Rosselot, Gelb, Crabb, and Hill et al., Prog. Growth Factor Res., 4:45-68 (1992)). Other studies have shown that vitamins A, C, and D are also required for chondrocyte maturation (Leboy; Sullivan; Iwamoto et al., Microscopy Res. and Technique, 28:483-491 (1994); Iwamoto et al., Exp. Cell Res., 207:413-420 (1993); Iwamoto et al., Exp. Cell Res., 205:213-224 (1993); Pacifici et al., Exp. Cell Res., 195:38-46 (1991); Shapiro et al., J. Bone Min. Res., 9:1229-1237 (1994); Corvol et al., FEBS Lett., 116:273-276 (1980); Gerstenfeld et al., Conn. Tiss. Res., 24:29-39 (1990); Schwartz et al., J. Bone Miner. Res., 4:199-207 (1989); and Suda, Calcif Tissue Int., 37:82-90 (1985)).
Transgenic mice and human cartilage defects have also provided information about endochondral ossification. Transgenic mice with deletions of the PthrP gene show premature hypertrophy of growth plate chondrocytes, demonstrating a role for PTHrP in cell proliferation and suppression of hypertrophy (Karaplis et al., Genes and Develop., 8:227-289 (1994)). Human mutations in the collagens II, IX, X, and XI are the genetic bases for mild to severe (lethal) cartilage dysplasias (Kivirikko et al., Ann. Rev. Biochem., 64:403-434 (1995)). Roles for sulfate transport (Hastabacka et al., Cell, 78:1074-1087 (1994)), sulfate metabolism (Franco et al., Cell, 81:15-25 (1995)), FGF receptor 3 (Shiang R. et al., Cell, 78:335-42 (1994)), and the transcription factor SOX9 (Wagner et al., Cell, 79:1111-1120 (1994)) in normal cartilage development have all been demonstrated by identification of genetic defects in human families.
The FGF receptor, sulfate transporters, and SOX9 are among the few examples of cellular proteins that have demonstrated roles in cartilage development. As outlined above, many of the proteins with critical roles in cartilage biology are either extracellular matrix proteins or signalling molecules. Thus, the genes and gene products instrumental to regulating the transition of chondrocytes from one stage to the next have yet to be fully characterized. Biochemical techniques used to identify matrix or intracellular components may not be sensitive enough to detect weakly or transiently expressed proteins. Furthermore, identification of cartilage defects in human or mouse mutants as a method to identify important cartilage or chondrocyte-specific proteins is limited by the number of mutants available and the labor involved in combined genetic and molecular approaches.
The present invention is directed to overcoming these and other deficiencies in the art.


A chip-to-chip communication system and interface technique. A master and at least two devices are interconnected with a signal line of a high speed bus. A capacitive coupling element, for example a diode, is employed to capacitively couple the interface of the device to the signal line. By employing the capacitive coupling element, along with a suitable signaling technique which supports capacitive information transfer, high speed rates of information transfer between the master and device over the signal line are achieved.

This invention relates to a chip-to-chip communication system. Chip-to-chip communication systems facilitate interactions between a number of devices. Typically the devices communicate with each other via a bus or a plurality of signal lines.
The term "chip-to-chip" refers to any implementation where a number of devices are inter-coupled together. The term "device(s)" is used to refer to one or more integrated circuits or cards which may include synchronous dynamic random access memories (SDRAM), double data rate (DDR) memories, micro-controllers, processors, memory modules, modem cards, and video cards, just to name a few. A memory system and computer system are ready examples of a chip-to-chip communication system formed from an inter-coupled group of integrated circuits or cards. The usage of the term "bus" refers to any arrangement of a plurality of conducting medium used to transport information between devices. Such conducting medium may be implemented in one of many ways including wires in a flex tape or patterned conducting lines on a printed circuit board, etc. For our purposes, one of a conducting medium used in a bus of a chip-to-chip communication system will hereinafter be referred to as a "signal line."
Thus, in keeping with the foregoing, an example of a conventional chip-to-chip communication system is illustrated in FIG. 1. Here, chip-to-chip communication system 10 includes master device 20 and a plurality of slave devices 30a to 30n, coupled by at least one signal line 40. In this example, the master device 20 may be any device capable of communicating with one or more other master devices (not illustrated) or with slave devices 30. Typically, slave devices 30a–n only respond to commands given by master device 20, and do not communicate with each other. More specific examples of chip-to-chip communication systems include a memory system having a controller directing interactions with a number of memory devices over a bus, or a computer system having a mother board with a central processing unit (CPU) communicating with a number of peripheral device cards.
One common class of slave devices includes memory devices, such as dynamic random access memory (DRAM). Such devices are characterized by limited access speeds. Access speeds for conventional DRAMs have significantly lagged behind the operating speeds pioneered in conventional CPUs. Thus, designers face a constant challenge in the development of memory systems having sufficiently high data throughput to fully utilize CPU performance capability.
With reference to FIG. 2, a chip-to-chip communication system implemented as a conventional memory system 45 is illustrated. Here, a controller 50 and a number of memory devices 60 are disposed on a circuit board (not illustrated). The memory devices 60 are directly coupled in parallel to the controller 50 over a wide bus 70. In this example, each memory device 60 has a dedicated portion of signal lines 80 directly coupled to the controller 50. In more detail, each memory device 60 is coupled to eight signal lines and all sixty four signal lines of wide bus 70 are coupled to controller 50.
It is well known that by utilizing this parallel approach to couple memory devices to the controller, the data throughput of the chip-to-chip communication system 45 may be improved. However, the width of the bus is limited by physical constraints, i.e., the available space and layout area of the circuit board. Thus, achieving additional data throughput by widening the bus (i.e., increasing the number of signal lines) has a maximum feasible limit.
Many different techniques have been employed in attempts to increase the data throughput of the conventional memory system. One attempt uses a relatively narrow bus and faster information transfer rates. "Information" in this context refers broadly to data, control and/or address information.
With reference to FIG. 3, a chip-to-chip communication system employing a relatively narrow bus is shown. In this example, a plurality of memory devices 105, are directly coupled to a controller 110 via narrow bus 115. Bus 115 comprises relatively few signal lines as compared to the parallel architecture of FIG. 2. This later conventional approach does not utilize a parallel architecture to achieve high data throughput. Thus, physical constraints tend to be less of a concern. Rather, in this conventional approach, controller 110 and memory devices 105 incorporate high speed interfaces. Here, high data throughput is achieved by transferring information between the controller and the memory devices at high transfer rates.
As information transfer rates are increased over a signal line, difficulties arise which impose a practical upper limit on these higher rates. With reference to FIG. 4A, a chip-to-chip communication system is shown having a signal line 220 coupling a plurality of devices 230a to 230c. The plurality of devices 230a to 230c are "directly coupled" to the signal line 220 at locations 240a to 240c. Two adjacent locations 240a and 240b span distance "d" to define a plurality of line segment 210a to 210d. Each line segment 210a–d may represent a common pitch between devices 230a to 230c. The term "directly coupled" refers to an electrical connection between a plurality of input/output (I/O) interface circuits 242a to 242c and signal line 220.
In this example, one line segment 210 is a conductor which may be modeled by electrical elements as shown in line segment model 250. The elements in the line segment model 250 describe the electrical behavior of each signal line segment. This electrical behavior is practically unnoticeable and therefore irrelevant at lower information transfer rates but becomes more significant to system performance as rates are increased. It is known to those skilled in the art that disposing a plurality of devices at equidistant points along a signal line causes the signal line to behave as multi pole low pass filter.
As the length "d" of the line segments 210a–d is decreased, the effective maximum operation frequency decreases. With reference to FIG. 4B, a representational graph of the signal line frequency response of the conventional chip-to-chip communication system with respect to three device I/O spacings is illustrated. Graph 410 depicts signal amplitude over a range of effective operation frequencies for signal line 220 (FIG. 4A) as a function of three device spacings d1, d2, and d3. Graph 410 illustrates three decreasing device I/O spacings d1, d2, and d3 and correspondingly decreasing cutoff frequency curves 412, 414, and 416.
With further reference to FIG. 4A, a plurality of "interface conductors" 255a to 255c typically couples each of interfaces 242a to 242c on devices 230a to 230c and signal line 220. The term "interface conductor" denotes all structures coupled to interfaces 242a to 242c and the signal line at location 240a to 240c. For example, interface conductors 255a–c might include bond wires, pins, modules or circuit card connectors, ball bonds, bond pads, electrostatic discharge protection devices, driver and receiver circuits and related interconnects. The interface conductors 255a–c, similar to the line segments 210a–d, may be modeled using electrical elements as shown in an interface conductor model 260. The electrical elements in interface conductor model 260 generally describe electrical behavior associated with the interface conductor 255.
When operating at high data transfer rates, the electrical behavior of the system depends, to a significant extent, upon the practical and physical attributes of the line segments 210 and the interface conductors 255. Here, the line segment model 250, includes inductive component 265, capacitive components 270 and resistive components 275. Interface conductor model 260 includes inductive component 280, capacitive component 285 and resistive component 290. It is well known by those skilled in the art that components such as the resistive components 290 and 275 introduce losses. The term "losses" may be used to describe mechanisms by which information transfer is not efficiently executed. Losses impose a limit on the rate at which the information may be reliably transferred. The magnitude of these losses are a function of the information transfer rate. As the information transfer rate is increased, losses also increase.
Interface conductor model 260 includes inductive component 280, capacitive component 285 and resistive component 290. These elements are directly coupled to the signal line 220 and, thus, become effectively "part" of signal line 220. Losses resulting from resistive component 290 increase as more devices are coupled to the bus.
With reference to FIG. 4A and FIG. 4C, a representational graph of the signal frequency response of the conventional chip-to-chip communication system with respect to three levels of dissipative loss is illustrated. Sources of dissipative loss include printed circuit board substrate, skin effect resistance of metal traces of the signal lines, and input resistance seen at the device I/O. Graph 420 indicates signal amplitude over a range of effective operation frequencies for signal line 220 (FIG. 4A) as a function of different quantities of dissipative loss. In the conventional chip-to-chip communication system, cutoff frequency decreases as the amount of dissipative loss decreases.
The capacitive component 285 plays a role in limiting the maximum useful information transfer rate. As the device input capacitance CI of capacitive component 285 is decreased, the maximum effective information transfer rate supported by the signal line increases. A representational graph of the signal frequency response of the conventional chip-to-chip communication system with respect to three device input capacitances is illustrated in FIG. 4D. Device input capacitance CI is inherent in elements of the I/O structures disposed on each device. These elements include, for example, bond pads, electrostatic discharge devices, input buffer transistor capacitance, and output driver transistor parasitic and interconnect capacitances relative to the device substrate. Typically, the input capacitance is present between a ground potential (not shown) and the signal line. Graph 430 depicts signal amplitude over a range of effective operation frequencies for signal line 220 (FIG. 4A) as a function of three input capacitances C1, C2, and C3 (where C1<C2<C3). In the conventional chip-to-chip communication system, cutoff frequency decreases as the device input capacitance decreases. Graph 430 illustrates the three input capacitances C1, C2, C3 and correspondingly decreasing cutoff frequency curves 432, 434, and 436.
As a result, the components of the interface conductor model adversely effect the maximum rate of information transfer. Here, as the information transfer rate increases, the magnitude of the losses associated with these components increases accordingly. The losses associated with these components impose an effective maximum information transfer rate limit.
In the conventional chip-to-chip communication system of FIG. 2, a parallel approach was used to achieve high data throughput. The information transfer rate in such systems tended to be too low for the loss components of the foregoing models to have any adverse effect on system performance.
In the narrow bus approach, the information transfer rate is increased relative to the information transfer rate employed in the parallel approach. The inductive, capacitive and resistive components in the interface conductor model and line segment model become more significant in determining the reliability of information transfer when the information transfer rate is increased. The resistive components in the interface and line segment models tend to degrade the integrity of the information in some proportion to the rate of information transfer.
One attempt to address the issue of increasing the speed of a data communications network, is described in U.S. Pat. No. 3,619,504. This patent describes a high speed network which employs coupling elements to couple information between a transmission line and receiver circuit. The coupling elements induce currents in "stub" lines which are terminated by a resistor. In operation, a voltage transition propagates down the transmission line and induces a current (in the opposite direction) in a stub line of each coupling element. An inductive coupling technique and associative circuit are employed to couple information between the transmission line and receiver circuit. The inductive coupling technique typically requires a stub line having a suitable length to facilitate current induction via the coupling element. This tends to impose a physical limit upon the interface between the receiver circuit and the transmission line and may be unsuitable for applications requiring tight space requirements. Thus, the inductive coupling technique may be limited by a minimum pitch requirement between adjacent receiver circuits due to the length of the stub line in each coupling element.
In sum, conventional chip-to-chip communication systems have employed a parallel approach to increase information throughput. However, use of this parallel approach is severely limited by space constraints. To overcome the limitations of the parallel approach, some conventional chip-to-chip communication systems have employed a narrow bus approach in which a high speed interface is incorporated into the devices. Here, high throughput is achieved by a high rate of information transfer. However, as the information transfer rate increases; inductive, capacitive and resistive components become significant limiting factors to the effective transfer of information. As the information transfer rate is increased, the magnitude of these components increases. This tends to impose an upper limit on the information transfer rate. In the conventional chip-to-chip communication system, the maximum effective operation frequency (or cutoff frequency) decreases as the pitch between adjacent device I/O are decreased. An inductive coupling technique may be viable towards increasing the effective information transfer rate in a chip-to-chip communication, but a minimum pitch requirement may be imposed between adjacent devices due to the required length of stub lines to effectuate inductive coupling.
Accordingly, there is a need to minimize the impact of losses resulting from the resistive component of the interface conductor model. Resistive components, inductive components, and capacitive components increasingly limit the reliability of information transfer as the information transfer rate is increased.
There is a need to provide circuits and techniques for increasing the effective information transfer limit beyond present maximum information transfer rates in conventional chip-to-chip communication systems. By increasing the maximum rate of information transfer further, data throughput may be increased, and higher system performance realized.

This patent is subject to a terminal disclaimer.

Chip-to-chip communication system using an ac-coupled bus and devices employed in same


Methods and kits for predicting the efficacy of antifolate (e.g., methotrexate) treatment of rheumatoid arthritis by detecting polymorphisms, particularly single nucleotide polymorphisms, in adenosine pathway genes.

Rheumatoid arthritis (RA) patients differ considerably in their clinical course and in response to treatment (1;2). Despite the fact that studies are supporting combination therapy to optimally suppress disease activity, most newly diagnosed patients start with monotherapy, with the antifolate methotrexate (MTX) being the preferred disease-modifying antirheumatic drug (DMARD) (3-6).
Randomized controlled clinical trials provide evidence that methotrexate alters the clinical course, although only about 40% of the patients show good clinical response (7-9). On the other hand, lack of response is associated with progression of joint damage and functional decline (6;10;11). However, it is not possible to predict which patients will respond since most studies concerning methotrexate efficacy have not investigated the predictors for response. Clear predictors for response to methotrexate will contribute to the allocation of effective therapy and will establish the reduction of disease activity and limit functional decline.
In candidate gene driven pharmacogenetic studies, polymorphisms in genes coding for proteins involved in pharmacokinetic or pharmacodynamic pathways related to the drug under study are selected and tested for associations with treatment outcome (12-14). For methotrexate, several studies showed that single nucleotide polymorphisms in genes coding for the folate pathway enzymes are associated with treatment response (15-17). Although methotrexate may act in rheumatoid arthritis through inhibition of folate pathway enzymes, more recent reports indicate that its response may also be related to the release of endogenous anti-inflammatory adenosine (18;19). Studies concerning other complex traits have indicated the relevance of polymorphisms in genes coding for enzymes related to adenosine release for clinical outcome (15;20-24). The current invention demonstrates for the first time that genetic variants in these genes are associated with methotrexate treatment outcome and exploits these associations for methods of diagnostics and treatment.

Genetic markers for prognosis of antifolate treatment efficacy

Academisch Zeikenhuis Leiden H.O.D.N. Lumc


A method and system for a color xerographic machine determines a lower bound for the ROS power levels so that color defects are not produced by light attenuation from one or more layers of toner particles on a latent image. The method computes a minimum ROS power level for the photoreceptor at its maximum and minimum charge levels. The minimum ROS power level is the level at which the discharge voltage does not drop beyond a maximum discharge voltage difference. The difference is related to a toner particle density that affects color reproduction. The minimum ROS power levels for the minimum and maximum photoreceptor charge levels are used to compute a functional relationship for minimum ROS power levels at other photoreceptor charge levels. Thereafter, the minimum ROS power level function may be used to compute minimum ROS power levels for other photoreceptor charge levels. The computed minimum ROS power levels may be used to control the power levels used during color reproduction performed by the machine.

In a typical electrophotographic printing process, a photoconductive member is charged to a substantially uniform potential to prepare an image panel on the surface for generation of a latent image. The charged portion of the photoconductive member is exposed to a light image of an original document being reproduced. The light radiation exposes the charged photoconductive member for selective dissipation of the uniform charge. The selective dissipation of the uniform potential forms an electrostatic latent image corresponding to the informational areas contained within the original document. The raster output scanner (ROS) is a component of the exposure station that directs light onto the photoreceptor to form the latent image in the xerographic process. After the electrostatic latent image is generated on the photoconductive member, the photoconductive member is rotated to a developer station containing developer material comprised of toner particles that adhere triboelectrically to carrier granules. A bias voltage transfers the toner particles from the carrier granules to the latent image to form a toner powder image on the photoconductive member. The photoconductive member is rotated to a transfer station where the toner powder image is transferred from the photoconductive member to a copy medium. The copy medium is transported to a fuser station where the toner particles are heated and pressed into the copy medium to permanently affix the powder image to the copy medium.
The foregoing generally describes a typical black and white electrophotographic printing machine. With the advent of multicolor electrophotography, a plurality of image forming stations is used to overlay color separated images in pixilated patterns for generation of three or four color images. One example of the plural image forming station architecture utilizes an image-on-image (IOI) system in which the photoreceptive member is recharged, reimaged and developed for each color separation. The charging, imaging, developing and recharging, reimaging and developing of the latent image to impose different color toner particles on the latent image may be performed in a single cycle or in multiple cycles. The multiple pass-machines produce only one color toner image during each pass of the photoreceptor and the image is transferred to the copy medium on the last pass through the machine. The single pass architecture offers a potential for high throughput, but the machine is expensive as it requires a charging, exposure and development stations for each color. While the multi-pass architecture is simpler and less expensive, its throughput is less than the single pass architecture.
Regardless of the architecture, the development of color separation images following the first application of toner particles is complicated by the attenuation of the exposing light by the toner particles. That is, the photoreceptor needs to receive the light in order to alter the voltage at the exposed photoreceptor area. If the light does not penetrate the toner particles, the photoreceptor is not set to a voltage level appropriate for attracting developer material in the amount required for good color quality. For example, if too little cyan toner color is applied over the yellow and magenta toner colors previously applied to a latent image, the resulting color does not properly reproduce the color in the original image.
For good quality imaging, a color image-on-image developer station must deliver consistent toner densities through the entire tone reproduction curve (TRC). Benchmark color systems control the TRC using photoreceptor charge voltages, developer bias voltages, and ROS intensity as actuators. Because different points along the TRC are sensitive to different actuators, the reproduction process can be controlled along the entire curve to produce consistent toner densities. However, systems that control the TRC by altering the power levels of the ROS need careful control, otherwise, the variations in the reproduced colors may be unacceptable. One may monitor the density of applied toner particles following application of the toner particles at a development station with densitometers that are used to regulate the bias voltages for development stations. This bias is the same across the entire photoreceptor; however, the voltage difference driving toner to the photoreceptor may vary substantially between bare and toned areas of the photoreceptor, if light attenuation by the toner layer is too large. Control of the TRC based on measurements of development on bare photoreceptor areas case does not adequately reproduce colors on photoreceptor areas having multiple layers of toner obtained from multiple development stations. To address this issue, control of ROS intensity may be used, but this method requires careful balancing. A wider range of ROS intensity may give better control of the TRC on bare photoreceptor areas; but, a narrower range may be required for overall color stability. Because the voltage difference due to ROS attenuation is highly variable, depending on charge level and photoreceptor properties, a constant range of ROS power either unnecessarily constrains toner density control, or allows too much variation in image-on-image density. Thus, variation of the ROS power range is required. The range must be adapted to the specific machine configuration, which includes photoreceptor, ROS, and exposure geometry. Too much, or too little, ROS power variation makes overall color stability unacceptable.

System and method for controlling the lower power bound for a raster output scanner in a color xerographic printer


Disclosed herein is a disc brake having a carrier at which a pair of pad plates is installed and a caliper housing slidably installed on the carrier and provided with a cylinder allowing a piston to be installed therein, the disc brake including an adjuster installed in the piston, a push rod installed in the cylinder and provided with a flange extending toward an inner circumferential surface of the cylinder, a ramp coupled to the flange to prevent rotation of the push rod and moving along with the push rod and seated in a seating groove provided at a rear wall of the cylinder, a spring case fixed to the cylinder and forming a predetermined accommodation space between the cylinder and the push rod, and an elastic member arranged in the accommodation space of the spring case to provide elastic force to the push rod and the ramp.

1. Field
Embodiments of the present invention relate to a disc brake which may stably return a piston when braking operation is terminated and improve the effect of return of the piston.
2. Description of the Related Art
A disc brake is a device that is generally used to slow a vehicle to a stop by forcibly pressing friction pads against both sides of a disc rotating together with a wheel of the vehicle.
To reduce brake drag that is caused by continuous contact between the disc and the friction pads after the braking operation, two solutions may be considered for such disc brakes. One solution is to move the piston backward using a sealing member and a roll-back chamfer. The other solution is to move the piston backward by applying a compression spring to pad plates, which are pressed against the disc.
FIG. 1 is a cross-sectional view illustrating a conventional disc brake, and FIG. 2 is a view illustrating moving the piston backward using a sealing member and a roll-back chamfer.
As shown in FIGS. 1 and 2, a disc brake 10 includes a pair of pad plates 11 to generate braking force by being pressed against a disc D, a carrier (not shown) to support the pair of pad plates 11, a caliper housing 20 installed at the carrier and provided with a piston 22 slidably installed in a cylinder 21 to apply pressure to the pair of pad plates 11, and a sealing member 30 interposed between an inner surface of the cylinder 21 and an outer surface of the piston 22 of the caliper housing 20. The sealing member 30 serves to seal the space between the inner surface of the cylinder 21 and the outer surface of the piston 22 to prevent leakage of brake oil and to allow the piston 22 to be moved forward in the direction of arrow A, as shown in FIG. 2, for implementation of braking and moved back to an original position thereof by resilience of the sealing member 30, by which the sealing member 30 recovers an original shape thereof, when the braking operation is terminated.
The sealing member 30 is formed in a shape of a ring to be inserted into a circular roll-back chamfer 23 provided in the inner surface of the cylinder 21, and has a quadrilateral cross section. In addition, the roll-back chamfer 23 to accommodate the sealing member 30 is provided with a slope 24 at a side of the opening facing the direction opposite to the direction of braking (indicated by arrow A) to allow the sealing member 30 to be deformed when the piston 22 is moved forward in the direction of braking, as shown in FIG. 2.
When the piston 22 is moved forward to perform braking, the sealing member 30 is deformed as shown in FIG. 2. When the braking operation is terminated, the sealing member 30 returns in the direction opposite to arrow A to an original state thereof shown in FIG. 1. Accordingly, the piston 22 is moved back to an original position thereof by the resilience of the sealing member 30. This action is referred to as roll-back. The return distance of the piston 22 depends on the deformed width L of the sealing member 30.
However, in the conventional disc brake 10, since the side of the sealing member 30 facing the direction in which braking is performed is a flat surface roughly perpendicular to the outer surface of the piston 22 as shown in FIG. 1, the deformed width L of the sealing member 30 is limited as shown in FIG. 2, and thereby the return distance of the piston 22 may be short. That is, the deformation of the conventional sealing member 30 is small, and thus increasing the return distance of the piston 22 may be limited. If the return distance of the piston 22 is short, the friction pads 12 attached to the pad plates 11 may not be sufficiently separated from the disc when the braking pressure is released, resulting in wear of the friction pads 12. That is, the amount of roll-back given according to the machining allowance of the cylinder 21 and friction between the sealing member 30 and the piston 22 may result in high drag.
Further, when the piston 22 returns to an original position thereof, the piston 22 may undergo knock-back, which refers to a phenomenon in which the piston 22 moves forward again by elastic force of the sealing member 30 after moving in the return direction. In addition, when the braking pressure is released, the caliper housing 20 slidably moved from the carrier returns to an original position thereof along with elastic return of the piston 22 by the sealing member 30. However, when the caliper housing 20 is moved leftward in this process, the piston 22 may undergo back slip, that is, slipping in the direction of forward (leftward) movement of the piston 22, which is caused by the sealing member 30 installed at the roll-back chamfer.
Meanwhile, in the case that a compression spring (not shown) is used to move the piston 22 backward, the compression spring is installed at the pad plate 11, which is pressed against the disc D, to provide elastic force in the direction opposite to that of pressing the pad plate 11 against the disc D.
However, when the compression spring is used, the amount of roll-back increases as the friction pad 12 wears, resulting in poor initial brake feel. Further, excessive roll-back of the piston 22 may occur due to the compression spring, resulting in a sinking brake pedal.


The problem of fiber or particle settling in well cement slurries is addressed by providing a fluid containing two fiber components of differing properties. Such a well treatment fluid, comprising a base fluid; a first fiber component that it substantially more dense than the base fluid; and a second fiber component that has a density close to that of the base fluid and is relatively flexible.

1. Field of the Invention
The present invention relates to cementing slurries containing particles and fibres. In particular, it relates to such fluids in which the sedimentation of the particles or fibres in the slurry is prevented or hindered. Such slurries find applications in well cementing operations.
2. Description of Related Art
The use of particles or fibres in well treatment fluids such as cements has been previously proposed. One such example is described in European Patent No. 1086057 which describes the use of amorphous cast-iron platelet particles in oil-well cements to provide added toughness and impact resistance. However, there is a large density difference between the particle and the base fluid—the cement slurry with which the particles are mixed—so special care must be taken to prevent the sedimentation of the particles. When the particles are metallic, for instance based on cast iron, the density difference is commonly around 5000 kg/m3. Preventing the sedimentation of these fibres is usually ensured by viscosifying the base fluid. The rheology of the base fluid is characterized by a minimum of two parameters, the high shear rate viscosity and the yield stress, which quantifies the low shear rate viscosity of the fluid. There are many drawbacks to viscosifying the base fluid, for instance increase friction pressure drops when the fluid is pumped through tubulars, difficulties in mixing it and increased cost due to the use of viscosifying agents.
EP 621 247 describes the use of selected particle size distributions for solid materials used in cementing slurries to provide slurries that are stable against settling or sedimentation.
EP 721 050 and U.S. Pat. No. 5,501,275 both describe fluids containing a base fluid, a first fibre or particle component and a second fibre component, and relate to the use of fibres in the fluid to limit the movement of particulate materials in the fluid such as sand or proppant particles

Well cementing slurries containing fibers


Apparatus for producing synthesis gas from a biomass feed in a closed, helical coil reactor utilizing a heat source such as a natural gas burner. The reactor includes the helical coil disposed in a reactor vessel with the heat source positioned toward a bottom of the reactor vessel. A heat shield is preferably disposed within at least an upper section of the helical coil, and the coil is placed adjacent to, but spaced from, a sidewall of the vessel so that convective heat may flow upwardly and around the individual coils of the helical coil. A lower section of the helical coil is preferably exposed to direct heat from the heat source. This lower section may exhibit a coil diameter that is greater than a coil diameter of the upper section. The biomass feed may be supplied to the helical coil from a mixing chamber including a spiraling screw valve.

1. Field of the Invention
The present invention relates to an improved gasifier/reactor fed by a biomass of cellulosic material such as granulated wood, rice hulls, chopped cane and the like, for the production of a gas selectively rich in hydrogen and carbon containing components such as carbon monoxide, carbon dioxide, and methane, which in turn may be converted into a selected end product fuel such as methanol or ethanol, or used as a feed gas for an industrial power plant.
2. General Background of the Invention
Gasification of wood, wood chips including sawdust, wood charcoal and other particulate cellulosic materials have become of increasing interest and importance because of the volatility of petroleum prices, dwindling of fossil fuels such as domestic petroleum and natural gas resources, and the increased dependence of the United States on international imports of these fuels. Gasification of coal and biomass has been practiced for over 100 years, and there are many varieties and types of gasifiers and methods of gasification.
In the instance of gasification of wood, wood chips and wood charcoal and other similar biomass fuels for the production of gas rich in combustibles, static grates or the equivalent have been utilized for supporting the fuel bed of progressively carbonized material and distributing the air, steam or other transport gas to support the pyrolysis gasification process. Vessels that have traditionally been used successfully for gasifying granular biomass such as wood chips and similar cellulosic material have been cylindrical, or somewhat wider or narrower at the grate level than at the surface of the fuel bed, according to the flow of feed and the forced air (or other gas) draft. Concerns with the settling of the fuel bed so that combustion takes place without the need to poke or otherwise stir the fuel bed have provoked a variety of vessel construction, none of which lend themselves to well to a high volume, precisely controlled, continuous process wherein the biomass fuel is efficiently converted to the target gas for supply to conversion into the ultimate fuel to be marketed or used. Prior art gasifiers have traditionally been large structures of brick and mortar, including complicated feed, blower and control systems. U.S. Pat. Nos. 5,551,958 to Antal; 5,507,846 to Coffman; 5,486,269 to Nilsson; 5,226,927 to Rundstrom; 4,655,891 to Atwood; 4,498,909 to Milner, et al; and 4,385,905 to Tuckerare are illustrative of the various reactors and processes which have been utilized for the conversion of biomaterials to a syngas. U.S. Pat. No. 1,901,170 to Karrick discloses the use of a helical coil in a closed loop for gasification of coal and coke; however the operation of such a unit with biomass material is unclear. Necessary feed and mixing mechanisms and gasifier structure for the range of temperatures, pressures and through rates are not disclosed or suggested.
Gasification of biomass fuels generally falls into one or more of the following categories: pyrolysis, air gasification, oxygen gasification, and anaerobic digestion. Pyrolysis is the breakdown of the biomass by heat at elevated temperatures (e.g., 400° F. to 1200° F.) to yield an intermediate gas which is ultimately transformed into a market fuel (gas or liquid such as methane or ethanol). The intermediate gas produced is dependent upon the feed source and the speed and temperature at which the pyrolysis occurs. Fast pyrolysis of finely divided biomass results in maximum intermediate (synthesis gas) gas yields. Inclusion of such things as oxygen and/or steam during the pyrolysis assists in the production of an intermediate gas containing carbon monoxide, carbon dioxide and hydrogen, useful in later conversion into such as ethanol, methanol, ammonia or methane. Other gas additions such as air or nitrogen may be used for synthesis gas having other make-up required for different end products. Anaerobic digestion may be utilized (usually in a secondary reactor) to facilitate various means for the conversion of the intermediate gas into one or more of these final fuels or products.
The difficulties in gasification include the conversion of all of the elements comprising the biomass fuel into gases containing the highest amounts of energy, for later conversion into the final products and the minimization of ash and char. In certain biomass fuels, gasification at lower temperatures produces oils and char requiring additional processing and likely, additional energy or waste in the process. Exposing the base fuel during the pyrolysis to air, water vapor or other components has a direct impact upon the products of pyrolysis, as does the temperature of the process and the duration thereof. By using any of the processes of the prior art, such as the fluidized bed, which is, at least, initially exposed to air and can be additionally exposed to such as oxygen, or others of the described input gasses, some portion of the fuel for gasification is consumed, as by oxidation (burning) effecting the output of the process by producing ash or other undesirable residue. Likewise, the startling size and complexity of installations for the effective production of synthesis gas are illustrated in the above cited patents.


An examination method for detecting abnormal electrochemical testing strip includes the steps of: applying a trigger voltage to a testing strip; injecting a target sample to the testing strip; obtaining a trigger current which is generated by injecting the target sample to the testing strip; comparing the trigger current with a first threshold, and determining whether the trigger current is lager than or equal to the first threshold; and when the trigger current is less than the first threshold, displaying a message for abnormality.

Field of Invention
The invention relates to an examination method for detecting abnormal testing strip and, in particular, to an examination method for detecting abnormal electrochemical testing strip.
Related Art
Electrochemical analysis method is commonly used in the substance examination or concentration examination, and developed into a test-and-know sensor due to its rapid and convenient examination. Further, the above mentioned sensor is commonly formed into a testing strip nowadays. The electrochemical analysis method can be applied to many fields, such as environment, agriculture, medicine or biochemistry analysis. The electrochemical analysis method is a high-sensitivity (heavy) metal examination method and can detect even a low concentration. In medicine, the domestic blood-glucose meter is a really successful case for the electrochemical analysis method applied to the testing strip.
The testing strip described in this invention is designed according to the electrochemical analysis method, and can be called an electrochemical testing strip. In general, the testing strip has a space therein for holding a target sample, and includes two electrodes so that the target sample and the reagent on the electrode surface (or the reagent contacting a part of the electrodes) can generate the corresponding electrochemical action, and therefore a current value can be detected according to the concentration of the target sample. In other words, concentration of the target sample can be deduced from the current value. The target sample is variable according to the application field of the testing strip, or the blood sample used in the blood glucose detection.
However, trigger current of the conventional electrochemical testing strip and method required for the electrochemical reaction is not quite high enough in value, so the sensing procedure is easy to be promptly started after the switch is turned on. Hence, examination for the abnormal condition can not be effectively executed (unless the testing strip is fully damaged or has a gross flaw), and therefore the sensing data acquired may be generated from the abnormal electrochemical testing strip and that will also be an error data. In practical, the ex-factory electrochemical testing strip lacks of a mechanism or design capable of effectively detecting the abnormal condition, such as abnormal circuit resistance of the testing strip or unsuitable enzyme content of the reagent for specific sample or testing target. Therefore, the user can't sense the abnormal condition of the testing strip, and thus continuously uses the abnormal testing strip to acquire the abnormal reading which will cause an erroneous judgment. Especially, when the testing strip is applied to the medicine use, for example, the blood glucose testing, the abnormal reading may further hurt the user's health and safety due to error data.
Therefore, it is an important subject to provide an examination method for detecting abnormal electrochemical testing strip while the testing strip is used, and the abnormal testing strip can display abnormal data instead of directly reading so that the erroneous judgment of the user can be prevented.

Examination method for detecting abnormal electrochemical testing strip


The invention provides methods for purifying bisulfite-treated nucleic acid samples.

Assessment of methylation of DNA is useful in many research, diagnostic, medical, forensic, and industrial fields. Key to this assessment is converting cytosine to uracil, but not methylcytosine to thymine. One basic method for such conversion, employing sodium bisulfite, is well known. Over the years, the method has been improved in attempts to overcome disadvantages that include tedious procedures, lengthy reaction times, and DNA degradation. The currently most commonly used protocol is taught by J. Herman, Proc. Natl. Acad. Sci. 93, 9821–26 (1996), incorporated herein by reference in its entirety. This method involves denaturation, reaction with sodium bisulfite in the presence of hydroquinone, and subsequent completion of the modification by treatment with NaOH. Despite the attempts to improve the protocol, current procedures still require pre-denaturation of the genomic DNA (gDNA) to single stranded DNA (ssDNA), preparation fresh solutions of sodium bisulfite (NaHSO3), typically about 3M, and inclusion an anti-oxidant (e.g., hydroquinone). The protocol also involves long reaction times and tedious clean-up procedures.
In addition, the currently employed sodium bisulfite protocols are plagued by reports of incomplete conversion, irreproducible results, and other problems. In some cases, the reaction results in significant DNA degradation (reportedly as high as 96%), making it difficult to obtain enough sample for further analysis. See. S. J. Clark et al. Nucleic Acid Research 2001, 29 no. 13, 65.
It has been discovered that bisulfite methods that employ magnesium bisulfite, polyamine compounds, and/or quaternary amine compounds provide useful alternatives to sodium bisulfite conversion reactions. These discoveries are the subjects of co-owned applications entitled "Method And Materials For Polyamine Catalyzed Bisulfite Conversion Of Cytosine To Uracil" (U.S. application Ser. No. 60/499,113 filed Aug. 29, 2003, and also application Ser. No. 60/520,942 having the same title and filed Nov. 17, 2003), "Method And Materials For Quaternary Amine Catalyzed Bisulfite Conversion Of Cytosine To Uracil" (U.S. application Ser. No. 60/499,106 filed Aug. 29, 2003, and also application Ser. No. 60/523,054 having the same title and filed Nov. 17, 2003), and "Method and Materials for Bisulfite Conversion of Cytosine to Uracil (U.S. application Ser. No. 60/499,082 filed Aug. 29, 2003, and also application Ser. No. 60/523,056 (5180P2) having the same title and filed Nov. 17, 2003), all of which are hereby incorporated by reference in their entirety.
Two widely reported methods of purification used in connection with bisulfite conversion reactions utilize either adsorbtive resins, such as the Promega Wizard resin or similar DNA binding resins, or dialysis. Given the importance of assessment of DNA methylation, it can be seen that there is a need for improved methodology for conversion of cytosine to uracil, and for the purification of the products of such conversion. Applicants have discovered such an improved methodology which is the subject of the co-owned application entitled: "Improved Bisulfite Method" (U.S. application Ser. No. 60/498,996 filed Aug. 29, 2003, and also application Ser. No. 60/520,941 having the same title and filed Nov. 17, 2003), all of which are hereby incorporated by reference in its their entirety.


The invention employs a blower of the type used by commercial landscapers. The device has an engine mounted on a frame. Shoulder straps attached to the frame allow the user to wear the device on his back leaving the hands of the operator free to operate other tools such as a chain saw or perform other tasks. Also, wearing the device on the back makes it easier to transport the device over long distances to the source of the fire or backfire to be started.

Description of the Prior Art
Every year, wild fires burn across the United States. Vast areas of forest land in the American mid-west such as Montana, Idaho and Wyoming burn every year. These fires are started by campers being careless with camp fires and lightning. The wild fires often spread quickly and threaten towns, homes and property.
In the year 2000 alone, 27,000 fire fighters combated 73,000 separate fires. These fires claimed over 6.3 million acres. The cost of fighting these wild fires is estimated to be 1 billion dollars. The total economic loss from fires, including property damages and loss of businesses, is estimated to be 10 billion dollars. More importantly, every year, many fire-fighters lose their lives combating the blazes.
Many types of equipment are used to combat wild fires. An effective tool is the use of airplanes to drop fire retardant chemicals and water on the affected area. Water is used to extinguish the blaze, whereas fire retardant chemicals are used to stop the advancement of the fire. Regardless of the advancement in firefighting equipment, the most work is done by fire-fighters on the ground.
Firefighters combat the blaze by extinguishing the fire directly or starting a backfire. A backfire is the controlled burn of forest in advance of the forest fire. By burning the land, a fire line is created. When the forest fire advances to the area burnt by the backfire, it can no longer advance for lack of fuel. Once a fire line is created by a backfire, the main blaze is allowed to burn itself out. This method is effective because the firefighters do not have to come in close proximity to the wild fire. However, backfires must be properly executed or they will become as great a problem as the original fire. It is important that the backfire advance in a direction toward the main forest fire. A sudden shift in winds can prevent the proper advancement of a backfire.
Firefighters on the ground use tools such as chain saws to create proper conditions for starting a backfire. Trees and heavy brush are cut and set ablaze when the conditions are optimal to cause a backfire to advance in a direction toward the main fire.
The prior art discloses several different types of apparatus using the exhaust of an engine to combat a fire. One such example is disclosed in U.S. Pat. No. 4,614,237 (Colodner et al.). Colodner et al. discloses a combination fire extinguisher and blower. An internal combustion engine powers the blower and includes a hose coupled to the exhaust pipe cover and the air inlet of the blower. The hose pipe exhausts gas into the blower when such gas is needed to extinguish a fire. A second hose is provided on the blower having one end secured to a sleeve fastened to an air cooled nozzle and is used to blow air or exhaust gas, whenever needed.
U.S. Pat. No. 5,848,652, issued to Bennett, discloses a fire suppression system for an engine compartment of a vehicle. A remotely controlled throttle valve disposed within the exhaust duct of the engine selectively diverts exhaust gas through a bypass duct for mixing with ventilation air flow. By mixing the gases and the air flow, the oxygen content is reduced in the air flow over the engine. The reduced oxygen content will inhibit combustion.
Another prior art device is disclosed in U.S. Pat. No. 5,154,238, issued to Buchan. Buchan discloses a fire protection apparatus having spray nozzles oriented adjacent engines of an airplane. Quick connect coupling secure a conduit to the spray nozzles and deliver a fire extinguishing agent such as carbon dioxide directly to the engine to extinguish a fire.

Air blower for extinguishing fires and method for extinguishing fires

Abstract: The device's blower generates a stream of air at high speeds. This stream of air can be used to feed a fire when the air is directed at a fire. When used to extinguish a fire, air from the blower is tapped from a point 180 degrees removed from the blower output and mixed with exhaust from the engine. This mixture is diverted through a Y-shaped valve into the airstream coming out of the blower. When the device is used to start backfires a fire is started. The airstream, without the mixture of air and engine exhaust can be used to both encourage the propagation of the fire and direct the fire towards the main wild fire. The ability to quickly spread the backfire in the proper direction is imperative because a sudden change in wind direction or other weather conditions could cause the backfire to become as big a problem as the original fire.


A process for the removal of vinylacetylene, ethylacetylene and 1,2-butadiene from C.sub.4 aliphatic hydrocarbon streams comprising, concurrently: (1) feeding hydrogen and a hydrocarbon stream comprising C.sub.4 hydrocarbons including butanes, butenes, butadienes and vinylacetylene to a distillation column reactor containing a bed comprising a hydrogenation catalyst of the type characterized by platinum, palladium or rhodium which is prepared as a distillation structure to selectively hydrogenate a portion of the vinylacetylene and the 1,2-butadiene and (2) fractionally distilling the reaction mixture to remove a heavier fraction and removing a fraction overhead comprising substantially all of the C.sub.4.

1. Field of the Invention
The present invention relates to the concurrent selective hydrogenation of vinylacetylene, ethylacetylene and 1,2-butadiene in an olefin rich C.sub.4 stream. More particularly the invention relates to a process utilizing hydrogenation catalysts in a structure to serve as both the catalyst and as a distillation structure for the simultaneous reaction and separation of the reactants and reaction products.
2. Related Information
Petroleum distillate streams contain a variety of organic chemical components. Generally the streams are defined by their boiling ranges which determine the compositions. The processing of the streams also affects the composition. For instance, products from either catalytic cracking or thermal cracking processes contain high concentrations of olefinic materials as well as saturated (alkanes) materials and polyunsaturated materials (diolefins). Additionally, these components may be any of the various isomers of the compounds.
Refinery streams contain a broad spectrum of olefinic compounds. This is especially true of products from either catalytic cracking or thermal cracking processes. These unsaturated compounds comprise ethylene, acetylene, propylene, propadiene, methyl acetylene, butenes, butadiene, amylenes, hexenes etc. Many of these compounds are valuable, especially as feed stocks for chemical products. Ethylene, especially is recovered. Additionally, propylene and the butenes are valuable. However, the olefins having more than one double bond and the acetylenic compounds (having a triple bond) have lesser uses and are detrimental to many of the chemical processes in which the single double bond compounds are used, for example, polymerization. Over the range of hydrocarbons under consideration, the removal of highly unsaturated compounds is of value as a feed pretreatment since these compounds have frequently been found to be detrimental in most processing, storage and use of the streams.
Boitiaux, et al in "Newest Hydrogenation Catalyst", Hydrocarbon Processing, March 1985, p. 51-59, present an overview of various uses of hydrogenation catalysts, including selective hydrogenation, utilizing a proprietary bimetallic hydrogenation catalyst. More particularly at page 56, the authors show that the only significant transformation of components is vinylacetylene to 1,3-butadiene with the improved catalysts in a stream also containing 1-butyne, 1,2-butadiene and olefins.
U.S. Pat. No. 4,067,921 discloses a process known as the Dow K Process, where acetylenes are hydrogenated in a diene stream containing principally 1,3-butadiene and trace amounts of vinylacetylene, ethylacetylene, and 1,2-butadiene, with substantial elimination of vinylacetylene with a small loss of 1,3-butadiene, but substantially no reduction in 1,2-butadiene (Table IV).
It is an advantage of the present invention that reduction of vinylacetylene, ethylacetylene and 1,2-butadiene is obtained in C.sub.4 olefin containing streams. It is a particular advantage that this may be achieved in a single reactive distillation column by using beds of function specific catalyst.

Process for concurrent selective hydrogenation of acetylenes and 1,2 butadine in hydrocarbon streams


This invention is a secure and long-lasting ground connection, or isolation terminal, for, for example, fiber optic cable installations. The isolation terminal has a proximal end with a hole in a conductive element for receiving a stud extending out from the terminal box, and a nut placed on the stud, or for receiving a bolt placed in the hole for being received by the terminal box. Surrounding and enclosing the conductive element with the hole is a walled structure which is adapted on its lower end to fit and cooperate with the external wall of the terminal box, helping to create a tight seal between the terminal box and the isolation terminal. The inside of the walled structure creates a cavity which is closeable by means of a close-fitting cap, for example. After tightly attaching the isolation terminal to the terminal, the cavity is filled with an insulator, like a dielectric gel, for example, and then the cap is closed to securely cover the cavity. This way, the electrical ground connection is protected against infiltration by the environment and resulting corrosion or decay.

1. Field of the Invention
This invention relates generally to electricity and electrical connectors. More specifically, this invention relates to an isolation terminal for securely connecting an electrical circuit to ground and for securely isolating the connection from the elements, so that the connection will be durable.
2. Related Art
In electrical circuits, it is common to connect the circuit to ground, which is the earth or some conducting body serving in place of the earth. There have been many conventional ways to make this electrical connection to ground. However, in some applications there is a special incentive for a secure and long-lasting ground connection. In fiber optic cable systems, for example, the remoteness and difficult physical environments for many ground connections require that the ground connections be particularly secure and long-lasting. Otherwise, failure of the ground connection will result in poor ability in locating or detecting the fiber optic cable, poor cable in general, service and expensive down-time and repair.


An anti-static resinous composition with permanent anti-static property is provided. The anti-static resinous composition comprises from 5 to 50 percent by weight of hydrophilic copolymer and from 50 to 95 percent by weight of thermoplastic. The hydrophilic copolymer is formed by self-emulsion polymerization. The monomer mixture used in the reaction comprises from 10 to 70 percent by weight of vinyl or propenyl macromonomer containing a polyethylene oxide chain and from 30 to 90 percent by weight of ordinary vinyl monomer. The thermoplastic is compatible with the hydrophilic copolymer. The resultant resinous composition has permanent anti-static properties.

1. Field of the Invention
This invention relates to resinous compositions, and more particularly, to an anti-static resinous composition which has a permanent anti-static property for preventing the resultant plastics from accumulating electrostatic charges thereon. Still more specifically, the anti-static resinous composition of the invention comprises a hydrophilic copolymer which has good heat-stability when mixed with thermoplastic under high temperature process conditions. Further, the hydrophilic copolymer can be compatibly mixed with the thermoplastic without the need to add any compatible agents thereto. The anti-static resinous composition is formed by mixing the hydrophilic copolymer with the thermoplastic at various ratios. The plastic articles formed from the anti-static resinous composition of the invention possesses excellent permanent anti-static property and will not suffer from disintegration or blooming.
2. Description of Related Art
Thermoplastics are widely utilized in the industry for making various kinds of plastics product with excellent insulation and medical properties such as high modulus, high impact resistance etc. They can be made by various processes such as extruding, rolling, injection and heat-formation.
One drawback to the thermoplastics, however, is that, due to their insulating quality, static electricity easily accumulates on the plastic articles made therefrom, which can cause electro-static damage to the related circuit parts in, for example, copy machines, faxes, printers, to name just a few, that are enclosed in plastic casings. Moreover, dust can be easily attracted by the static electricity and accumulate on the plastic casings or covers of these office machines. In printing factories, for instances, the static electricity on the plastic parts of a high-speed printing machines can cause the paper sheets passing therethrough at high speeds to be attracted astray, usually causing the so-called paper path jam in the machine. In a winding machine for tapes made of plastics, for instances, the static electricity produced due to the high-speed winding of the tapes, when accumulated to a certain great amount, can cause a sudden electric-static discharge in the form of an electric arc, which could then cause electrical shock to the operating personnel or damage to the machines.
In the semiconductor industry, the transistor elements on IC chips, due to their extremely small sizes, are very sensitive to the static electricity accumulated on the plastic packages. A static charge with a potential in the range of 50 to 300 V (volt) can cause severe damage to the transistor elements in the ICs. A human body carries an average of 1 to 2 kV (kilovolt) of static electricity. When touching the ICs by hand, the static electricity on the human body can cause damage to the transistor elements therein. Therefore, during the manufacture and transportation of the ICs, they should be put in containers made of anti-static materials.
Several solutions have been proposed to prevent the electrostatic damage. The first solution is to coat a layer of anti-static material on the surfaces of the plastics by, for example, a dipping, wiping, or spraying process. The anti-static material is usually a moisture-absorbing interfacial agent which can prevent the accumulation of static electricity on the coated plastics. One drawback to this kind of anti-static material is that the anti-static effect thereof decreases as the ambient humidity decreases. Moreover, the coating of this anti-static material can easily peel off the surfaces of the plastics. For a circuit enclosed by a plastic casing, this could result in the undesired consequence of contaminating the circuit elements enclosed therein. Should the coating of the anti-static material peel off, the plastic casing must be surface treated again so as to form a new coating of the anti-static material thereon.
The second solution for enhanced anti-static effect is to mix the thermoplastic with a low molecular weight anti-static agent in the process of making the plastics. The molecules of this anti-static agent can migrate to the surface of the plastics and attract the moisture molecules from the ambient atmosphere to form a thin water film on the surface of the plastics. This thin water film can prevent the buildup of static electricity on the surface of the plastics. Various compounds have been proposed to serve as this kind of anti-static agent, as the N-oxyethylated alkylamines disclosed in U.S. Pat. No. 3,575,903; the alkanolamines and polyalkylene glycols disclosed in U.S. Pat. No. 3,525,915; and the lauric diethanolamide disclosed in U.S. Pat. No. 3,873,645. One major drawback to these anti-static agents, however, is that, the ingredients thereof could filtrate out to the surface of the finished plastic articles, thus causing the undesired effect of blooming on the same. Moreover, after a long period of use, the anti-static effect may decrease.
The third solution for enhanced anti-static effect is to add a high molecular weight anti-static agent in the process of making the plastics. This kind of anti-static agent can allow the plastics to have a permanent anti-static effect and is classified in terms of its compatibility with the thermoplastic into two types. The first type has less compatibility with the thermoplastic while the second type has more compatibility.
The first type of the anti-static agent, when mixed with the thermoplastic, enrich a highly dense continuous phase on the surface of the plastics, allowing the anti-static agent to exhibit enhanced anti-static effect on the same. Various compounds have been proposed to serve as this kind of anti-static agent, as the polyether ester amide disclosed in U.S. Pat. No. 5,338,795 and Japan Patent Heisei-4,337,344; and the epichlorohydrincopolyer disclosed in U.S. Pat. Nos. 4,588,733, No. 4,775,716, No. 4,857,590, and No. 5,216,046. To achieve the highly dense continuous phase on the surface of the plastics, however, a suitable compatible agent must be added to the mixture of the anti-static agent and the thermoplastic. Without the adding of the compatible agent, the thermoplastic will lose its characteristics.
The second type of the foregoing anti-static agent is formed by copolymerization of a vinyl monomer containing polyethylene oxide chains with an ordinary vinyl monomer. When mixed with thermoplastic, the vinyl monomer ingredient in the anti-static agent provides compatibility, while the polyethylene oxide ingredient provides the desired anti-static effect. Since this type of anti-static agent has more compatibility with the thermoplastic, it can exhibit a continuous phase on the surfaces of the plastics, allowing the anti-static agent to provide a permanent anti-static effect and excellent mechanical properties. The copolymerization is customarily an emulsion polymerization process, which allows the anti-static agent to possess the qualities of high impact-resistant capability and matting. Various compounds have been proposed to serve as this kind of anti-static agent, as U.S. Pat. No. 4,543,390; Japan Patents Showa-60 144,314; Showa-60 195,143; Showa-61 261,344; Showa-62 48,756; and Heisei-1 126,358.
From the foregoing, it is apparent without question that the permanent anti-static agent will be a key player in the future of plastic applications. However, although the high molecular weight copolymers such as polyether ester amide, epichlorohydrin copolymer, and high-molecule-weight polyethylene oxide (high M.W. PEO), are effective permanent anti-static agents, they exhibit some drawbacks when mixed with the thermoplastic. For instance, compatible agents should be added to some of the anti-static agents to preserve the mechanical properties of the resultant plastics. Some of the anti-static agents require the addition of alkaline salts, interfacial agents, or other additives to help them exhibit the anti-static property. When interfacial agents are added, the processability of the resultant plastics will be limited. The anti-static agents made by emulsion polymerization can be provided with backbones that are compatible with the thermoplastic and provide side chains that have anti-static property, so that, when they are mixed with the thermoplastic, no compatible agents are required while nonetheless providing excellent anti-static properties. One drawback to these anti-static agents, however, is that, since they are made by emulsion polymerization, the emulsifying agent will be left as a residue therein during separation, purification, or mixing processes. The residue of the emulsifying agent will cause the resultant plastics to have poor appearance. In addition, the residue on the surface of the resultant plastics causes the resultant plastics to have poor post-processability.

Resinous composition with permanent anti-static properties

Industrial Technology Research Institute


A RAKE receiver circuit generates combining weights based on channel estimates and combining statistics that comprise channel coefficient statistics, noise statistics, and channel estimation error statistics. Together, these statistics incorporate the relationships in noise and channel estimation across two or more RAKE fingers, and thus improve combining weight generation. Exemplary determination of statistics comprises channel coefficient cross-correlations, noise cross-correlations, and channel estimation error cross-correlations. Determination of the statistics can be varied based on, for example, the assumption of default or nominal signal models. Further, statistics determination can be configured for different receive and transmit diversity scenarios, wherein combining statistics can be determined on a per diversity signal basis, or jointly for two or more diversity signals, or in a mixed separate/joint method wherein one or more statistics are determined on a per signal basis and one or more statistics are determined across the signals.

The present invention generally relates to RAKE receivers and particularly relates to the computation of the RAKE "combining weights" used in such receivers.
RAKE receivers represent a well-known approach to multipath reception, particularly in Direct Sequence Code Division Multiple Access (DS-CDMA) wireless communication systems. With multipath, a transmitted signal follows multiple propagation paths and the intended receiver thus receives multiple "versions" (images) of the transmitted signal, with each signal image generally suffering from different path delay, phase, and attenuation effects.
RAKE receivers exploit multipath by allocating each of two or more RAKE "fingers" to one of the incoming signal images. In that sense, then, each finger is tuned to a particular one of the multipath components of the incoming composite received signal and each finger thus receives its own version of the originally transmitted signal. By estimating the channel effects, e.g., phase and attenuation, and by properly accounting for the differences in path delays, the individual output from each finger may be RAKE combined with the outputs from the other fingers to provide a combined RAKE output signal whose signal-to-noise ratio (SNR) generally is improved by the summed contribution of each finger's despread output signal.

Method and apparatus for combining weight computation in a DS-CDMA RAKE receiver


The present invention provides a data transfer network receiving a higher evaluation overall than conventional ones from various perspectives such as the number of effective nodes, the required number of links, and the required maximum node capacity. The present invention is a data transfer network of a hyper configuration in which each node is an element of m (m is 2 or more) different local networks. Further, at least one of the local networks to which the respective nodes belong is a hub network and, when a node belongs to a local network other than a hub network, the local network is a full mesh network.

1. Field of the Invention
The present invention relates to a data transfer network in which a plurality of nodes is connected.
The data transfer network of the present invention can be applied to networks in general, such as the general Internet, public communication networks, company-internal communication networks, LAN, computer networks, distributed computer networks, distributed router networks, exchange networks, switch networks that are used in devices that perform data communications such as routers and so forth, data communication networks that link CPUs, memory, and so forth, and data communication networks in LSI such as CPU, for example.
2. Description of Related Art
Data transfer networks in which a plurality of nodes is connected that perform distributed processing to respective nodes include (A) bus networks, (B) ring networks, (C) hub networks (star-shaped networks), (D) full mesh networks, (E) hyper expanded (hypercube) networks, and so forth. A hypercube network is a hyper structure network that comprises a bus network or ring network as a plurality of local networks (sub-networks).
Furthermore, it is considered that, in the future, the number of terminals contained in data transfer networks will increase and that data transfer speeds will increase. Hence, it is important to increase the amount of data (traffic) that can be processed by the whole network, that is, to raise the traffic capacity. It is therefore necessary to investigate optimization and increased efficiency and so forth of the network configuration.
The capacity of the five types of network above will be described with reference to FIGS. 12 to 14.
FIG. 12 shows the relationship between the numbers of nodes contained in the respective networks and the effective node number. The effective node number indicates the traffic that can be processed by the whole network with the number of nodes serving as the units.
FIG. 13 shows the relationship between the number of nodes contained in the respective networks and the required link number. The required link number is the number of connections between nodes required in order to configure the network.
FIG. 14 shows the relationship between the number of nodes contained in the respective networks and the available maximum node capacity. The available maximum node capacity indicates the processing power of the nodes for which the required processing power is maximum among the nodes contained in the network. FIG. 14 shows the available maximum node capacity in arbitrary units.
As shown in FIG. 12, when the networks are configured by using the same numbers of nodes, the effective node number grows smaller in order starting with the full mesh network as the largest, followed by the hub network, the hypercube network, the ring network, and then the bus network.
However, in a full mesh network, one node is connected to all of the other nodes. As a result, as shown in FIG. 13, the required link number is huge in comparison with the links required in networks of other configurations.
On the other hand, in hub networks, signals from all the nodes pass through a relay device at the core of a star shape. Hence, as shown in FIG. 14, the available maximum node capacity has a huge value in comparison with networks of other configurations.
Conventionally, when distributed processing has been performed in the whole network by a plurality of nodes, a hypercube network has been adopted. In a hypercube network, the required link number is smaller than in a full mesh network, the available maximum node capacity is smaller than that of a hub network, a ring network, and a bus network, and the effective node number is larger than that of a ring network and a bus network. In a hypercube network, the number of local networks of which a certain node is an element is expressed as the order. In the case of a conventional hypercube network, the order is three or four. Although the effective node number increases when a higher-order hypercube structure rendered by raising the order (m) is used, the required link number (=2×m) also increases. Further, in cases where the nodes gradually increase, the initial number of nodes is often small. In a hypercube network, there is the problem that the efficiency drops when the number of nodes is small. In addition, as shown in FIG. 12, when 400 nodes are used, the effective node number is only 12 in a fifth-order hypercube network containing bus network as a local network. Therefore, this is hardly adequate in comparison with the 200 nodes of a complete mesh network and the 133 nodes of a hub network.
As a result, a new data transfer network with a higher than conventional overall evaluation from various perspectives such as the effective node number, the required link number, and the available maximum node capacity is desirable.


A projection apparatus includes a light source module and a micro-electro-mechanical-system (MEMS) mirror. The light source module outputs a plurality of illumination beams having different transmission paths. The MEMS mirror is disposed on the transmission paths of the illumination beams. Each illumination beam propagates to the MEMS mirror respectively, and the illumination beams are respectively reflected by the MEMS mirror to project on a plurality of positions within an imaging region, wherein the transmission paths of the illumination beams transmitted from the light source to the MEMS mirror are not intersected with the imaging region.

1. Field of the Invention
The present invention is directed to a projection apparatus and more particularly to a projection apparatus capable of projecting an image having a plurality of sub imaging regions arranged in an array.
2. Description of Related Art
In recent years, due to a combination with mobile projection demands, a pico projection apparatus may be further widely applied in various fields, such as home, business, traveling, games, mobility and so on and has become one of the most important technologies to be developed in the projection apparatus field.
Generally, a pico projection apparatus is referred to a portable projector which is weighted under 1 kilogram. The projection technologies that are widely applied to pico projection apparatuses include the LCD projection technology, the liquid crystal on silicon (LCoS) projection technology, the digital light processing (DLP) projection technology and the laser scanner projection technology. Therein, the laser scanner projection technology has advantages, such as high luminance, wide color gamut, focus-free and long lifespan due to the usage of a laser source. On the other hand, the laser scanner projection technology applies a micro-electro-mechanical system (MEMS) to fabricate related mirror elements and systems and thus, also has advantages, such as being small-volume, light-weight, having low power consumption and stable functionality, etc. Moreover, a laser scanner projection apparatus may be embedded into a mobile device due to being small-volume and become more convenient in carrying.
However, the laser light source adopted by the laser scanner projection technology has characteristics, such as having high collimation, small divergence angles, etc., and thus, when the laser light source used by the laser scanner projection technology is directly incident on a human eye, a permanent damage will be caused on a retina. Accordingly, every country in the world sets up safety criteria on the usage of the laser light source. For instance, according to the laser safety criteria "ICE 60825-1 2000" set up by the International Electrotechnical Commission (IEC), it is regulated that an output power of a continuous-wave visible laser beam is not allowed to be greater than 1 milliwatt (MW). However, if doing so, an image luminance capable of being outputted by the laser scanner projection technology is limited.
Moreover, an image resolution which may be achieved by the laser scanner projection technology is also decided by a size and a rotation speed of an MEMS mirror. Typically, when the MEMS mirror has a greater size or a faster rotation speed, the image resolution will be higher. However, the greater size of the MEMS mirror leads to more limitations to the rotation speed, while the smaller size of the MEMS mirror leads to higher cost. As a result, the rotation speed and the size of the MEMS lens are not easily improved simultaneously, which also construct limitations to an image resolution that can be achieved by the laser scanner projection technology.
Accordingly, in order to meet requirements on both mobile projection and quality of projected images, how to overcome technological bottlenecks in the laser scanner projection technology is indeed one of the important subjects for research and design staffs to pay attention to.

Projection apparatus having MEMS mirror with plural projection paths


A color vision characteristic detection apparatus has a storage section, a generation section, and a presenting section. The storage section stores a basic color chart containing portions colored in colors different from each other. The generation section performs a predetermined conversion processing with respect to the basic color chart to generate an adjusted color chart for one color vision characteristic type so that it is difficult for a person who has a visual characteristic of the one color vision characteristic type to distinguish the adjusted color chart from the basic color chart. The presenting section presents the basic color chart and the adjusted color chart to a user.

1. Field of the Invention
The invention relates to an apparatus for detecting the color vision characteristic of a user to adjust an image presented by an information processing apparatus and in particular to improvement of the convenience of the apparatus.
2. Description of the Related Art
In recent years, a color display (display formed of a liquid crystal panel, an organic EL panel, etc.,) has been installed in a personal computer, a mobile telephone, a PDA (Personal Digital Assistant), further in a vending machine of tickets, etc., for example, and has been useful for presenting various pieces of information.
However, the display may not necessarily be easy to understand for those who have congenital color vision impairment or acquired color vision impairment. Hitherto, various methods for presenting an image in a mode, which facilitates color vision perception, have been proposed ("Diversity of color vision and color vision barrier-free presentation, part 1", Okabe and Ito, Cell Technology, Shujunsha, Vol. 21, No. 7, July 2002, pp. 733-745 and "Diversity of color vision and color vision barrier-free presentation, part 2", Okabe and Ito, Cell Technology, Shujunsha, Vol. 21, No. 8, August 2002, pp. 909-930).
However, there are large variations among individuals in the color vision impairment state in such a manner that the color vision impairment type differs; in fact, the mode facilitating color vision perception as in the related art described above varies from one person to another. However, hitherto, as for the variations among individuals, for example, the types of congenital color vision impairment (there are three types of P, D, and T) have been only able to be set. A user often does not know his or her type. As with the acquired color vision impairment, if the degree of difference between individuals is large, it is not easy to make setting for each individual within the given types.

Color vision characteristic detection apparatus