There is provided a calibration apparatus for calibrating a jitter measuring circuit for outputting a jitter measuring signal corresponding to a value of jitter contained in an input signal, having a signal inputting section for sequentially inputting the first input signal having first period and the second input signal having second period to the jitter measuring circuit and a gain calculating section for calculating a gain in the jitter measuring circuit based on the jitter measuring signals to be outputted out of the jitter measuring circuit respectively with respect to the first and second input signals.

1. Field of the Invention
The present invention relates to a calibration apparatus, a calibration method, a testing apparatus and a testing method. More specifically, the invention relates to a calibration apparatus for calibrating a jitter measuring circuit for measuring jitter in an input signal.
2. Related Art
Conventionally, there has been known a circuit for measuring jitter on a chip. The circuit measures the jitter of a high-frequency signal generated within the chip and outputs amplitude of the jitter in the signal-under-measurement by converting into amplitude of voltage.
A value of jitter of the signal-under-measurement may be obtained by dividing output amplitude of a jitter measuring circuit by a jitter output gain of the jitter measuring circuit. Conventionally, a designed value based on circuit design is used for the jitter output gain of the jitter measuring circuit. There is also a case of giving a signal having known jitter to the jitter measuring circuit from the outside of the chip to measure the output amplitude of the jitter measuring circuit.
However, with refinement of semiconductor manufacturing process, characteristics of circuit elements such as transistors, resistors, capacitors and the like in the jitter measuring circuit have come to vary widely due to fluctuation of the process. Then, an actual jitter output gain may have a large error to the designed value.
In the method of inputting the signal having the known jitter from the outside of the chip, it is required to input a signal having equal frequency with the high-frequency signal on the chip from the outside so that the characteristic of the jitter measuring circuit is equalized with the case of measuring the high-frequency signal on the chip. However, it is difficult to supply the signal of high frequency of about several GHz for example to the chip from an input pin of the chip.
Still more, because the quality of the high-frequency signal easily deteriorates, the amplitude of the jitter of the signal inputted to the jitter measuring circuit is not equal with the amplitude of jitter in the signal applied from the outside of the chip. Therefore, the amplitude of the jitter of the signal actually inputted to the jitter measuring circuit becomes unclear and it is difficult to accurately obtain the jitter output gain.
Still more, although the jitter output gain may be accurately obtained by inputting the high-frequency signal to the jitter measuring circuit without deteriorating the signal quality, there arises a problem that it requires a great amount of design cost in such a case.

Calibration apparatus, calibration method, testing apparatus, and testing method


A local area network uses standard ANSI FDDI LAN concentrator stations and a first set of mutually reverse-direction data buses or loops, in conjunction with an additional set of mutually reverse-direction data paths. The standard FDDI protocols when applied in the context of the particular connections of the concentrator station operate in the event of a break in the data path terminating at an input or output port, to reconfigure the station to interconnect the buses in a manner which routes data around even multiple breaks in the buses, to thereby maintain communication integrity.

This invention relates to local area communication networks, and more particularly to local area networks (LAN) according to ANSI Fiber Distributed Data Interface (FDDI) standards, which LAN are arranged for enhanced reliability in adverse environments.
Modern vehicles such as aircraft, ships and the like include sophisticated computer systems for sensing the environment, evaluating the sensed information, and for controlling the vehicle and/or its payload in response to the evaluations. Such vehicles, and military equipment whether fixed or mobile, require highly reliable communications among the sensors, evaluation equipment, and the controlled devices. The reliability is often provided, at least in part, by redundancy. Thus, in addition to redundant computers for performing the evaluations, and redundant sensors and controlled devices, if possible, the interconnections should also be redundant. In warships, for example, there may be a relatively large number of sensors, including a plurality of radar, sonar, infrared and other sensors, all of which must be interconnected with command centers and with evaluation computers, and with guns, missiles and their controllers.
In the past, such warships have provided redundant point-to-point communication or data transmission paths or links between each mission-critical pair of devices, with the redundant paths differently routed within the ship to avoid the possibility that single-point damage can disrupt the communication. With this arrangement, all equipments remain interconnected, and any one device or sensor only becomes isolated from the system in the event of breaks on both of its separately routed, mutually alternate paths. Thus, extensive damage to the ship is likely to break several data paths, but these data paths are not likely to include both data paths to a particular device, so all devices are likely to remain interconnected. With the advent of computerized control, each computer (including the redundant computer) is required to provide a sufficient number of input-output (IO) ports to allow connection by at least first (primary) and second (alternate) paths to each of the devices which it serves. Specialized military computers with large numbers of input-output ports are available for such interconnections. The rapid expansion of control requirements tends to quickly render obsolete any computer with a fixed number of IO ports, and specialized computers with yet larger numbers of IO ports then become necessary.
With a view toward improved reliability and reduced cost, attention has been directed toward the use of a standardized local area network (LAN) in conjunction with a plurality of microprocessors, such as are in common commercial use, for performing the same functions as the special-purpose computers together with their point-to point communication paths. Such a LAN arrangement allows the distributed microprocessors to perform multiple functions, thereby providing another level of, and increasing the redundancy of the computing portion of the system, and also allows ready expansion of the system to include sensors or controlled devices as their need is discovered. The use of a standardized or commercial-type LAN further reduces cost, without, it is hoped, sacrificing usability.
The American National Standards Institute (ANSI) has generated standards and protocols for token-passing fiber-optic LAN systems, which are known by the acronym FDDI, which stands for Fiber Distributed Data Interface. It would be desirable, if possible, to use the FDDI standards in relation to high-reliability systems such as those described above. At this time, FDDI-based systems are being introduced into shipboard applications, as described, for example, in an article entitled "All Aboard FDDI", by Adams, published at pp 13-17 of the December, 1991 issue of Military and Aerospace Electronics magazine. However, the FDDI standards provide only limited redundancy, and so cannot be used for mission-critical communications.
In FIG. 1, a standard FDDI local area network includes first, second and third standard FDDI stations or connection nodes 1, 2 and 3. Each standard station includes first input and output ports 1i and 1o, respectively, and second input and output ports 2i and 2o, respectively. Input-output port 1i, 2o is also known as an A port, and input-output port 2i, 1o is also known as a B port. As illustrated in FIG. 1, the first output ports lo of each of the three standard stations 1, 2 and 3 are connected by fiber-optic transmission paths to the first input port 1i of the next standard station. For example, a transmission path 11 connects from output port 1o of station 1 to input port 1i of station 2. Similarly, a transmission path 12 connects from output port 1o of station 2 to input port 1i of station 3, and a transmission path 13 connects from output port 1o of station 3 to input port 1i of station 1, thereby forming a first loop, designated generally as 20, by which data can flow in the direction of arrow 24 among stations 1, 2 and 3. As also illustrated in FIG. 1, the second output ports 2o of each of the three standard stations 1, 2 and 3 are connected by fiber-optic transmission paths to the second input port 2i of the next standard station. For example, a transmission path 14 connects from output port 2o of station 1 to input port 2i of station 3. Similarly, a transmission path 15 connects from output port 2o of station 3 to input port 2i of station 2, and a transmission path 16 connects from output port 1o of station 2 to input port 2i of station 1, thereby forming a second loop designated generally as 22 by which data can flow in the direction arrow 26 among stations 1, 2 and 3. In this context, a transmission path is a path by which signal travels essentially unchanged from one location to another. A path may include cable, connectors, repeaters, switches, attenuators, and the like, the presence of which does not affect the signal.
Each station includes a Media Access Control unit which is associated with one, but not both, input-output ports, so that one of the two loops is designated as the main or primary loop.
The system as illustrated in FIG. 1 includes only three stations for simplicity of explanation, but could include a large number of such stations, connected in a similar manner. As illustrated, each station is connected to the next station by means of two fiber-optic transmission paths, as for example station 1 is connected to station 2 by transmission paths 11 and 16, in which data flows in mutually opposite directions. An envelope designated 28 represents the practical fact that the two fiber optic transmission paths 11 and 16 are often combined into a single multifiber cable. Similarly, envelopes 30 and 32 represent the combining of fibers 12 and 15 into a cable 30, and the combining of fibers 13 and 14 into cable 32. The FDDI network as so far described in conjunction with FIG. 1 is used by connecting sensors, computers (and their associated operator inputs) or controlled devices to externally accessible data paths associated with each station, such as path 58 associated with station 1, and paths 59 and 60 associated with stations 2 and 3, respectively. In operation, a token is produced at the primary output port of a station when it has transmitted all its current information, and the next station on the primary loop either seizes the token to make time available for its own transmission, or retransmits the token on the primary loop or ring to the next station when it has no data to transmit. Thus, the ability to transmit unimpeded on the common bus steps from station to station with the token. Reception is not dependent on the token, and all stations may, essentially simultaneously, receive data which is relevant to the stations.
On a vehicle such as a ship, it may be advantageous to route cable continuously from one end of the vehicle to the other end, connecting to various equipments along the way. This corresponds to that portion of FIG. 1 including stations 1, 2 and 3, and data paths included in cables 28 and 30, but without the data paths corresponding to those of cable 32 of FIG. 1. As described below, the two end stations "wrap" so that communications occur back and forth among the stations. This linear arrangement is termed a "root" topology The root topology has the advantage of reduced cabling requirement, but introduces the distinct disadvantage that a single break anywhere in the system results in undesirable isolation of portions of the system. This disadvantage could be remedied by a complete additional set of station nodes and interconnection cabling. However, this more expensive and complex than simply running the additional cable for the return link corresponding to cable 32 of FIG. 1.
Concentrators are allowed within the FDDI standard for expanded system connectivity. As described in an article entitled "Using Redundancy In FDDI Networks", by Ocheltree, published at pages 261-267 of the proceedings of the 15th Conference on Local Computer Networks, Minneapolis, Minn. Sep. 30-Oct. 3, 1990, and in an article entitled "The DECconcentrator 500 Product", by Tiffany et al., published at pp 64-75 of the Spring, 1991 issue of Digital Technical Journal, concentrators include a plurality of master ports in addition to the A and B ports. FIG. 2 illustrates a concentrator station in accordance with FDDI standards. In FIG. 2, an FDDI concentrator station 4 includes an A port with 1i and 1o ports, a B port including 2i and 2o ports, and a path 61 for connection to a local sensor or other device, just as in the standard FDDI stations of FIG. 1. In addition, concentrator station 4 of FIG. 2 includes a plurality of "master" (M) ports, which are available for connection of additional single stations 62a, 62b, 62c, . . . 62n. Such an arrangement might have utility, for example, in a LAN in which a multi-story building is to be interconnected. For this purpose, each floor might have a concentrator station, with the A and B ports connected with other concentrators on other floors in a loop as described in conjunction with FIG. 1, and at each floor, the M ports of the concentrator for that floor are connected by individual two-fiber cables to each separate single station For example, if concentrator 4 of FIG. 2 were on the fourth floor of such a building, port M1 would be connected to fourth-floor equipment station 62a by way of a cable 63a, port M2 would be connected to fourth-floor equipment station 62b by way of a cable 63b, etc. The A and B ports of the concentrator would, of course, be connected to other stations on the third and fifth floors. In the terminology of FDDI, the additional single stations 62 of FIG. 4 are part of a "tree", which in the case of single stations as in FIG. 4 cannot be expanded to further levels. If, in FIG. 2, each single station 62 were to be replaced by a concentrator station which was connected to its higher-level concentrator station (station 4 in FIG. 1) at one of its A or B ports, additional stations at a third level could be connected to the various M ports of the second-level station, to thereby create a tree with many levels. In such an arrangement, the lower-level stations all couple back to loop through concentrator 4, and are termed "singly homed". On the other hand, if the other of the A and B ports of the second-level concentrator is connected to another concentrator station which is also in the loop, each low-level station can couple to the loop through two (or possibly more) paths, and they are said to be "dual homed", all as described, for example, in the above mentioned Ocheltree article. In operation of the concentrator as illustrated in FIG. 2 when connected in a ring, as described, the token is received at the A1i port as in FIG. 1, and is routed in succession to each of the active M ports and to the stations connected thereto, i.e. from port B to port M1, then down through all the stations in the M1 path, then to M2, and through all the stations in the M2 string,... When the token has progressed through all the stations associated with all the M ports of the concentrator, it is made available at the B1o output port on the ring. Thus, the use of concentrators in a loop gives rise to delays which do not occur in standard stations, and their use is contraindicated unless necessary It should be noted that the paths between M ports of a concentrator station and the next following station are under continuing self-test during those intervals in which it is not being used for data.
FIG. 3a illustrates one possible configuration of bus connections within a standard or concentrator station, taken as standard station 1 for definiteness. In FIG. 3a, first and second directional couplers 40 and 42, respectively, have their main through lines coupled to each other and to input port 1i and output port 1o. The branch lines 44 and 46 of directional couplers 40 and 42, respectively, are coupled to active circuits illustrated as a block 56, which may include light detectors and modulators. Similarly, third and fourth directional couplers 50 and 48 have their through paths coupled to each other and to input and output ports 2i and 2o, respectively, and their coupled branch lines coupled to active circuit block 56. Suitable directional couplers include the well-known star couplers. Those skilled in the art know that this arrangement couples signals directly from input port 1i to output port 1o, and from input port 2i directly to output port 2o, and also couples the active circuit portion 56 to receive signals from the input ports 1i and 2i of standard station 1, and to couple signals therefrom to output ports 1o and 2o of station 1, but has the disadvantage of splitting the transmission power and thereby reducing the signal-to-noise ratio. In many applications, this will be of no consequence, but when large numbers of stations are to be interconnected, the cumulative loss of the couplers may exceed the regenerative power of the various stations.
Lower through loss at each station is permitted by the use of a switched "Trunk Coupling Unit" (TCU), illustrated in FIG. 3b. In FIG. 3b, station 1 receives signal through input port 1i, which is applied to a moving-mirror fiber-optic switch 98. Switch 98 allows signal to be routed directly from input port 1i to output port 1o when that station or node is shut down or deprived of power, which is a fail-safe bypass mode of operation. In normal operation, when the station is powered up, switch 98 couples signal from input port 1i to the active portions 56 of the node, and from the active portion to output port 1o. The operation of the TCU associated with ports 2i and 2o is similar.
The FDDI standard provides for error recognition, and for reconfiguring the station in response to errors for improving reliability. FIG. 4a is similar to FIG. 1, but includes an assumed break in a transmission line. While standard stations are described, the following discussion is equally applicable to concentrator stations. As mentioned, the transmission lines are actually coupled into cables including at least two paths, as for example cable 28 includes the two transmission paths 11 and 16 extending between stations 1 and 2. As a result, a break in one cable almost invariably breaks both optical fibers therein. The FDDI standard takes cognizance of this likelihood, and arranges its error detection circuits within each station to recognize the existence of faults, which include (a) a fault in the transmission path terminating at a 1i input port, and (b) a fault in the transmission path which starts at a 1o output port. The (a) type of fault may be termed an "upstream" fault, and the (b) fault may be termed "downstream", relative to the "main" data path or loop. In FIG. 4, a large "X" is placed over multifiber cable 28, thereby indicating that it is broken, possibly as a result of environmental or hostile action. As to station 1, the break is a downstream "b" fault, and as to station 2, it is an "a" type upstream fault. The FDDI standard requires the station subject to an upstream fault (in this example, station 2) to disconnect its 2i input from its 2o output and reconnect or "wrap" it to its 1o output, as illustrated by dashed path 70 in station 2. The disconnection of input port 2i from output port 2o is of no consequence, because any data applied to output port 2o cannot traverse data path 16 of cable 28 anyway. The FDDI standard also prescribes that a station subject to a downstream fault (station 1 in the example) must disconnect its 1i input port from the 1o output port, and reconnect or wrap it to the 2o output port, as illustrated by dash line 72 in station 1. As in the case of station 2, disconnecting input port 1i from output port 1o makes no difference, as data applied to data path 11 of cable 28 cannot traverse the break. The FDDI wrap protocol results in formation of a third loop to replace the broken first loop 20 and second loop 22. The third loop extends from output port 1o of station 2, through path 12, ports 1i and 1o of station 3 to path 13, then through input port 1i, path 72, and output port 2o of station 1, through path 14 to input port 2i of station 3, and out of output port 2o of station 3, through data path 15 to input port 2i of station 2, and finally through path 70 back to output port 1o of station 2. Thus, a single break has no significant effect on the communications among stations 1, 2 and 3 (although the delay may increase somewhat).
FIG. 4b is similar to FIG. 4a, differing only in that a second break in the cabling is shown, illustrated by a large "X" over cable 30. This break obviously isolates station 2 from stations 1 and 3. Station 1 still experiences a downstream fault, and responds by producing internal reconfiguration path 72. Station 3 experiences an upstream fault, and responds by reconfiguring itself by wrapping its 2i input port to its 1o output port, just as station 2 did in FIG. 4a. The wrap path in station 3 is designated 74. The wrappings provided by reconfiguration paths 72 and 74 of stations 1 and 3, respectively, form yet another loop which includes stations 1 and 3, and paths 13 and 14. In addition to the isolation of station 2 from stations 1 and 3 by the breaks of cables 28 and 30, station 2 is further isolated by the operation of the wrap specified by the FDDI protocol, which requires disconnection of paths 11 and 15 from station 2. As mentioned, the illustrated system includes only three stations, for simplicity of explanation. It should be understood that station 2 of FIG. 4b may actually represent a plurality of stations, and that the wrap specification will result in those additional stations forming their own interconnected loop, which, however, is totally isolated (by the multiple breaks) from the loop including stations 1 and 3. For mission-critical data communications, isolation of whole sections by damage to two unrelated data paths may not be acceptable. It should be noted that the looping data paths in an FDDI system are often illustrated side-by-side, as is shown by the alternate placement of data path 14 in the form of a dot-dash line 14b adjacent to data path 13 in FIG. 4b. This configuration results in the use of the terminology of formation of a "U" or "horseshoe" path instead of an alternative "loop" path when a wrap occurs. Thus, reconfiguration forms a horseshoe or a loop, depending upon the form or topology of the circuit which one has in mind, but the horseshoe and the loop are equivalent terms in this context.
Thus, while it would be desirable to use the FDDI system for all shipboard communications, including mission-critical data, the possibility of total isolation of portions of the communications system due to multiple breaks in the transmission cable makes it unusable for mission-critical applications. It might be possible to use an FDDI system for auxiliary communications, while using point-to-point communications for mission-critical applications, but this would not help the key problems of expandability of an existing system, cost, and the need for special-purpose computers. If the FDDI system standards are modified to achieve the reliability goal, the cost benefits of commonality with commercial systems are lost.
A SAFENET study group established by the Navy has conducted a review of LAN for mission-critical applications, and is in the process of generating SAFENET I standards based on IEEE 802.5 "free-token" protocol, which standard specifies that the two fiber transmission lines be separately routed, and adopts "ring hop", which amounts to abandoning a defective loop or ring and using the operational loop. The free-token protocol is not considered advantageous, because the hold time at any station is not controlled, and thus priority messages may be delayed excessively. The SAFENET group has also at least partially generated SAFENET II LAN standards. The SAFENET II standards define a timed token ring pursuant to FDDI standards, but in which the dual counter-rotating rings are separately routed. It supports a single failure, but degrades in the presence of additional failures, and therefore is no better than FDDI.
An improved communication system is desired.


Blades of increased blade angle may be retrofitted onto existing compressor rotor wheels as replacement blades whereby higher performance and efficiency without replacing the rotor wheel may be achieved. The base attachments of replacement blades are provided with lateral extensions or flanges and the rim of the compressor wheel is provided with recesses straddling the grooves to accommodate the flanges. The leading edge of the replacement blade is positioned circumferentially for support only by the platform extension thereby limiting the mean and vibratory stresses in the leading edge of the airfoil and maximizing damage tolerance.

The present invention relates to compressor blades and methods of replacing compressor blades with blades having a different blade angle and particularly relates to compressor blades having a platform with one or more side flanges forming an extension for supporting a leading edge of the blade. The present invention also relates to such blades in combination with a modified compressor wheel groove and methods of retrofitting blades having a different blade angle than the blade angle of the blades being replaced on the wheel.
With the ever present need for higher performance and efficiency for compressors, new and improved blade designs have evolved with increased blade angles. For example, the higher performing and more efficient airfoils may have a greater twist than prior compressor blade airfoils and thus have a greater circumferential extent between leading and trailing edges in a direction along the periphery of the compressor wheel. It will be appreciated that the compressor wheel has a rim with a plurality of circumferentially spaced grooves for receiving bases of the compressor blades. For example, the groove may extend axially or slightly off axis and may comprise a dovetail configuration having a pair of circumferentially spaced radially outwardly converging side walls for receiving a correspondingly configured base attachment of the compressor blade. The blades are typically characterized as axial entry or slightly off axis entry blades. The blade base attachment has a radially outwardly facing platform surface which lies flush with the rim of the rotor wheel when the blade is installed. These configurations of blades and wheel grooves limit replacement of the blades to substantially identical blades. Otherwise, the entire compressor rotor wheel would require replacement to accommodate the newer higher performing and more efficient airfoils.
In large gas turbines used for generating electricity, power companies regularly water wash the turbines as soon as any performance degradation is noticed. The water wash is sprayed into the turbine near the hub at the compressor end and the fluid is flung out into the flow path cleaning the blades. As a result of this water wash, water droplets impact the first stage compressor blades causing significant erosion along the leading edges of the airfoils and especially at the hub of the airfoils where the airfoils meet the platform. Performance degradation and potential for failure of the airfoils causing extensive rotor damage oftentimes result. Consequently, there is a need to replace compressor blades when the airfoils are damaged, e.g., eroded due to water washing and foreign object damage, and more generally to provide blades with increased blade angles relative to the blade angles of the blades extant in the compressor.

Compressor blade platform extension and methods of retrofitting blades of different blade angles


A duct joint structure for assembling a duct used for air conditioning or venting equipment, an assembly tool for assembling the joint portion, an assembly method of a duct, and a hanger for the duct with the duct joint structure. A duct joint structure includes at least two duct plate members arranged substantially at right angles in a sectional view. An end of a first plate member is bent substantially in accordance with the orthogonal relation, and the second plate member is formed at the forward end thereof with a U-shaped groove to accommodate the bent portion of the first plate member. A guide rail is protruded at not less than 90 degrees with respect to the outer surface of the second plate member from the side thereof spaced from the U-shaped groove.

Conventionally, the duct used for air conditioning or venting equipment (FIG. 12) is formed in a cylinder having a rectangular section by connecting two pairs of plate members 1, 2 using a joint structure of what is called "the button punch snap seam" as shown in FIG. 10 or what is called "the Pittsburgh seam" as shown in FIG. 11.
The former joint structure is such that the forward end portion of a plate member (first plate member) 1 constituting one joint portion is bent substantially at right angle, an end 1A of the bent portion is fitted into a U-shaped portion 2A at the end portion of a plate member (second plate member) 2 constituting the another joint portion thereby to form a joint. In this case, what is called "the return stops" 1a are formed at the end 1A on the first plate member 1 and adapted to engage an engaging portion 2b formed at the end of the second plate member 2. The forward end portion of the first plate member 1, once fitted as shown in FIG. 10b, therefore, would never come off. Therefore, the jointing work is very simple and requires no trouble other than fitting.
For the latter "Pittsburgh seam", on the other hand, as shown in FIG. 11, a bent end A1 at the forward end portion of a plate member (first plate member) 1 constituting one of the joint portion is fitted into a U-shaped portion 2A at an end portion of a plate member (second plate member) 2 constituting the other joint portion. Then, a protruded end portion 2c of the second plate member 2 is bent along the side 1b of the first plate member 1, as shown in FIG. 11b thereby to form a joint. In this case, the end 1A of the first plate member 1 is fixed (pressed) from above by the protruded end portion 2c of the second plate member 2. Once the joint structure is complete, therefore, the first plate member 1 would never come off. In addition, the double fitted structure of the joint including the first plate member 1 and the second plate member 2 has a considerably improved strength and a high hermeticity.
Consequently, a duct joint requiring hermeticity employs the "Pittsburgh seam".
In current practice, the work of forming the joint of the button punch snap seam and the Pittsburgh seam described above, i.e., the duct assembly work, is performed by the worker hitting a corner 4 of the plate member 1 or the neighborhood thereof to fit it into the second plate member 2. Actually, however, the joint is made of plates (steel-plate or the like) as thin as 0.3 to 1.2 mm. Strictly speaking, therefore, the plate member 1 or 2 is not sufficiently linear to allow the bending work for easily fitting the plate members along the longitudinal direction of the duct. As a result, the fitting work requires a considerable magnitude of force and a multiplicity of hits by the hammer. The fitting work (assembly work), therefore, must be performed by a very strong person. In addition, the hitting sound of the hammer is so harsh to the ears as to possibly cause the worker a hearing problem. In the absence of suitable soundproof equipment, therefore, the complaints against the noise would rush in from the neighboring residents. A similar problem is posed by the work of bending the protruded end portion 2c of the second plate member 2 described above.
Further, the time consuming manual work of said assembly is low in efficiency and the duct is therefore expensive to fabricate.
In addition, the manual work makes it impossible to assemble the duct (fit the joint) at the construction site where the working time is limited. Unavoidably, therefore, the duct is presently assembled and stored in the factory, and transported the site using a truck and crane in accordance with the progress of the field work. Also, the delivery of an assembled duct in a truck encounters the problem of a bulkiness for the weight, leading to a very low transportation efficiency. What is more, the duct cannot be securely bound by rope or the like as it would be deformed. The result is a high risk of dropping the assembled duct in transit.
Furthermore, when hoisting the duct to the desired building floor by crane at the site, the small weight and the bulkiness exposes the hoisting work to the direct effect of the wind. It is therefore very difficult to deliver the duct into desired position by crane.
Another very troublesome problem posed by the bulkiness for the duct suppliers is that temporary storage of the duct where it is to be mounted interferes with the water or electricity work conducted concurrently. Also, the bulkiness is a factor which makes it impossible to store a large amount of standardized ducts in the factory. Even in the custom production, storage of completed ducts requires a large space.
Also, the conventional duct hanger, as shown in FIG. 25, is composed of an angle steel member 50 cut to the width of a duct 10 and having each end thereof formed with a hole 50a through which to apply a rod member 30.
In such a case, the duct work for an ordinary building requiring ducts of a variety of widths makes it necessary to prepare the angle steel member meeting the varying width of the duct. Also, this hanger, as shown in FIG. 24, must always be hanged by a pair of steel rod members for structural reasons. As a result, the place where the hanger can be installed is limited by the building structure and equipment. Another inconvenience is the fact that the duct is hanged at unnecessarily short pitches on the inner periphery side of the corners thereof. In addition, the angle steel member, when hanged by the ends thereof with steel rods, is liable to undesirable rotate about the steel rod members.
Another disadvantage of the conventional duct hanger system is that since the duct is only placed on the angle steel member , an air flow, if any, in the duct is a frequent cause of duct vibrations and noises in cooperation with the angle steel member.
The present invention has been developed in view of the above-mentioned situation, and the object of the invention is to provide a duct joint structure, an assembly tool, a duct assembly method and a hanger most suitable for the duct with the joint structure, which is not bulky and therefore convenient for storage or transportation, can be fitted quickly, and can be assembled easily even by a worker of less than average strength with a minimum of assembly noises.

Duct joint structure, assembly tool, duct assembly method and hanger


A method of dynamically determining a mass airflow per cylinder in order to control operation of an internal combustion engine includes first initializing a mass airflow per cylinder (MAC) value. A manifold pressure (MAP) signal, a mass airflow (MAF) signal, and an induction air temperature (IAT) signal is then received. An estimated manifold pressure is calculated from the MAF, the IAT, and the initialized MAC. A filter is applied to the MAP. A manifold pressure error is determined from the estimated manifold pressure and the filtered manifold pressure. A product is computed of the manifold pressure error and the initialized MAC. The product is adapted. A mass airflow per cylinder is computed, as a second product, based on the adapted product and the initialized MAC. Engine operation is controlled based on the mass airflow per cylinder.

Various methods for determining mass airflow per cylinder for an internal combustion engine exist. One common method for dynamically calculating a mass airflow per cylinder uses volumetric efficiency. This method requires volumetric efficiency tables that characterize engine breathing.
As defined, volumetric efficiency tables require a considerable amount of controller memory. Each value in the table must be individually calibrated to meet different engine characteristics. Once calibrated the volumetric efficiency tables are not always an accurate representation of engine breathing during transient operations. Eliminating the volumetric efficiency tables would be advantageous to the mass air per cylinder determination.

Mass airflow rate per cylinder estimation without volumetric efficiency map


A convenient, time-efficient, easy-to-use method for creating a substrate covering comprising graphic images, such that the substrate covering can be substantially opaque to an observer looking from one side of the substrate (allowing him to see an image), yet the observer is able to see through the substrate covering from the other side of the substrate, or such that an observer would be able to see the images as well as objects beyond the substrate, comprising the steps of (1) creating an outline for the substrate covering; (2) creating at least one artwork; (3) launching a window wizard, which allows a user to select the position of the covering with respect to the substrate; at least one artwork; and at least one primer in accordance with the desired visual effects; (4) selecting the position of the covering with respect to the substrate; at least one artwork; and at least one primer in accordance with the desired visual effects; and (5) sending the window wizard output for printing onto a substantially clear laminate that could be applied to the substrate, wherein stacked layers of the selected artwork and selected primers are printed with perforations onto said laminate, wherein the perforations of the stacked layers are aligned.

Advertisers and merchants desire the ability to display graphic images on a wide variety of surfaces. In recent years, transparent surfaces such as windows, glass partitions (as found in shopping malls), and the like have attracted a great deal of attention as substrates for advertising media.
In certain applications, if a graphic article is applied to a transparent substrate, such as a window, it is desirable that the image be visible when viewed from one side of the window, while leaving the window and image substantially transparent when viewed from the other side of the window. For example, if the image is to be mounted on a window of a vehicle, such as a bus or taxicab, it is desired that passengers be able to see clearly through the window, while pedestrians outside of the vehicle see the graphic images.
In other applications, if a graphic article is applied to a transparent substrate, it is desirable that the viewer be able to see the image as well as objects beyond the substrate. For example, in such structures as banks where security is of importance, not being able to see out through the windows can present serious security problems, endangering the wellbeing of the bank customers and employees. Therefore, if the image is to be mounted on a window of a bank, it is desired that the bank customers inside the bank be able to see the advertising or promotional image, while bank employees (or security personnel) inside the bank be able to see clearly through the window.
Other applications may include applying two images to both sides of a laminate—one on each side—to be applied to a transparent substrate, where the first image is visible from one side of the substrate and not the other, and the second image is visible from the other side but not the first, while the viewer can still see through the substrate from either side.
Graphic articles achieving these visual effects typically are multi-layer film constructions with a light-colored, opaque film adapted to receive an image on one surface and a dark, light-absorbing film on the opposite surface. Numerous perforations through the film layers create an optical illusion of "transparency" through the graphic article.
In a unidirectional application, the multi-layer film constructions are stacked and the perforations are sized and spaced such that, when observed from the imaged side, a viewer has a tendency to focus on the image; however, when observed from the other side, the viewer has a tendency to see through the graphic article, leaving the window unobstructed.
In the see-through applications, the multi-layer film constructions are stacked and the perforations are sized and spaced such that, when observed from the imaged side of a single-sided graphic article, or either side of a double-sided graphic article, a viewer has a tendency to focus on the image or look through the graphic article, leaving the window unobstructed.
In all cases, vision through the graphic article can be obtained in either direction when the level of illumination perceived through the graphic article from the far side of the graphic article sufficiently exceeds the illumination reflected from the near side of the graphic article.
U.S. Pat. No. 4,673,609, to Hill, discloses a method of painting one-way graphics onto windows by the use of a mask applied to the window where paint goes through the holes to adhere directly to the glass. There are many problems associated with this method:
1. If the mask does not adhere properly, the paint will bleed under the mask and create unsightly irregular or ragged patterns of dots.
2. Removal of the mask may remove portions of the color or lift entire dots from the surface of the glass.
3. Removal of the graphics from the glass is labor intensive, requiring the use of aggressive window cleaning techniques, and the washed off or scraped off paint particles can stain the surrounding areas such as window frames or sills, wall areas, landscaping and walkways.
5. Multiple coats of paint are required to achieve the one-way graphics: first a dark (usually black) coat is applied, and then after the black coat has dried, at least one coat of the background color is required to cover the black coating.
6. One-way graphics painted directly onto glass require a significant investment of time—both in the application of several coats of paint and in the labor-intensive removal methods required.
A considerable advance in respect of such conventional methods is represented by the teachings of U.S. Pat. No. 5,773,110, to Shields: a window to be provided with a display product is masked with masking paper. A perforated panel is cut to fit the window and attached over the masking paper. The perforated panel is painted with an image that is desired. Once the painting is completed, the panel is taken away from the masking paper. The painted panel with the one or more layers of paint thereon is applied to the window. The perforated panel could have an adhesive coating that would have a protective backing liner to protect the adhesive. The perforated panel is peeled or separated from the backing masking paper, thus, leaving the holes of the perforated panel free as well as holes in the painted liner.
Problems comparable to the ones of Hill—even though less severe—exist with the teachings of Shields: if the adhesiveness of the masking paper used is potent, more paint than desired might be removed from the perforated panel (which has one or more layers of paint) while it is being peeled or separated from the backing masking paper. Alternatively, if the adhesiveness of the masking paper used is feeble, some of the holes of the perforated panel might not be freed during the peeling process.
Also, even though the method of Shields is less time consuming than Hill's, it is still desired to further improve on the time investment needed in the production of these graphic panels.
As can be readily seen, these methods of hand-painted graphics and other contemporary methods do not possess all of the desirable advantages required to adequately create unidirectional and see-through graphics. Thus, there is a need for a method for creating these graphics. The present invention satisfies that need.

Method for printing unidirectional and see-through graphics


A device for stopping a diesel engine can properly control an engine stopping operation even if an engine rotation signal is not transmitted due to disconnection of a signal line at the time of the engine stopping operation and can prevent an engine stopping actuator from being burnt even if the engine does not stop due to mechanical trouble in a stopping mechanism. A contact 1a of a key switch 1 is turned from an ON terminal to an OFF terminal, whereby a transistor TR3 of a engine stopping operation section 8 us turned off. A transistor TR4 is turned on by a discharge of a capacitor C4, and a transistor TR5 and a relay switch 10 to follow are turned on to actuate a solenoid 11 to shut off fuel supply through a stopping mechanism. If a signal is not input into an engine rotation detection section 6, or, if the engine does not stop due to mechanical trouble in the stopping mechanism, the transistor TR4 is automatically turned off with expiration of a setting time defined by the capacitor C4, and the solenoid 11 returns to an initial state.

1. Field of the Invention
The present invention relates to a device for stopping a diesel engine, particularly to a compulsory stopping apparatus of the engine by shutting off fuel body or air supply.
2. Description of the Related Art
Conventional method for stopping the diesel engine is to compulsorily limit the fuel supply or the intake air supply by closing an intake valve disposed in an intake air system.
The applicant has proposed a device for stopping a diesel engine in which, by an engine stopping signal outputted when a key switch is turned off, engine rotation is detected and an engine stopping actuator is driven, in Japanese Utility Model Publication No. 3-17160 and in Japanese Utility Model Publication No. 3-83341.
In the stopping device as described in the former publication, while a drive signal is kept outputted to the engine stopping actuator, the detection of the key switch is invalidated to prevent the engine from restarting by an erroneous operation of the key switch before the engine stops completely. In the stopping device as described in the latter publication, when a predetermined time lapses after the key switch is turned off, the rotation detection is stopped to prevent a solenoid from being burnt out by an electric current exceeding the maximum rating even if the engine does not automatically stop while failing to cut off the fuel supply due to a mechanical trouble in a stopping mechanism.
In the prior art stopping devices as described, the drive of the engine stop actuator is controlled by detecting the rotation of the engine. It becomes difficult in such an arrangement to adequately drive the engine stopping actuator if the rotation detection signal of the engine stops due to disconnection of the signal line.


A microchannel structure has microchannels formed therein. The microchannels are to transport a coolant and to be proximate to an integrated circuit to transfer heat from the integrated circuit to the coolant. At least one of the microchannels has a length extent and has a first section at a first location along the length extent and a second section at a second location along the length extent. The first section of the microchannel has a first aspect ratio and the second section is divided into at least two sub-channels. Each sub-channel has a respective second aspect ratio that is greater than the first aspect ratio.

As microprocessors advance in complexity and operating rate, the heat generated in microprocessors during operation increases and the demands on cooling systems for microprocessors also escalate. A particular problem is presented by so-called "hotspots" at which circuit elements at a localized zone on the microprocessor die raise the temperature in the zone above the average temperature on the die. Thus it may not be sufficient to keep the average temperature of the die below a target level, as excessive heating at hotspots may result in localized device malfunctions even while the overall cooling target is met. This issue may be applicable to proposed cooling systems in which a coolant such as water is circulated through narrow channels (known as "microchannels") which are close to or formed in the die.
Another issue that may be encountered in microchannel cooling systems is the total pressure drop experienced by the coolant through its circulation path. The higher the pressure drop, the greater the demands on the pump that circulates the coolant. If higher pumping capacity is required, it may be necessary to include a larger and/or more expensive and/or less reliable pump. Pump size may be especially critical, since space may be at a premium, as is the case in notebook computers and other portable computer systems.
Still another issue that may be encountered in microchannel cooling systems is potential difficulty in connecting tubes for the coolant path to the potentially delicate cover of a microchannel assembly.
Yet another issue relates to fabricating microchannels that have a high aspect ratio (ratio of height to width). Generally speaking, higher aspect ratios in microchannels provide higher heat transfer rates and lower pressure drops. However, the production processes that may be employed in accordance with known practices to form high-aspect-ratio microchannels may be more expensive than other production processes that produce microchannels having smaller aspect ratios.
Another issue is how to reduce pressure drop by shortening the flow length without changing the geometry of the channels (i.e., to keep parallel flow geometry channels). This may allow for improved manufacturability.

Integrated circuit coolant microchannel assembly with targeted channel configuration


In one embodiment, first and second driver circuits are arranged interposing a matrix of pixels. A timing control circuit is electrically connected with the first and second driver circuits. The first driver circuit including a first sequential circuit is electrically connected with the odd scanning lines, and supplies scanning signals to the odd signal lines in order. The second driver circuit including a second sequential circuit is electrically connected with the even scanning lines, and supplies the scanning signals to the even scanning lines in order. The timing control circuit generates first and second synchronization signals, and supplies the first synchronization signal to the first driver circuit and the second synchronization signal to the second driver circuit. The first and second driver circuits supply the scanning signals to the scanning lines in order for every line upon receiving the first synchronization signal and the second synchronization signal from the timing control circuit.

Generally, a liquid crystal display device having such features as a light weight, a thin shape, and low power consumption is used as a display device. The liquid crystal display device is equipped with an array substrate, a counter substrate arranged opposing the array substrate, and a liquid crystal layer held between the array substrate and the counter substrate.
The array substrate includes a glass substrate. On the glass substrate, a plurality of signal lines and scanning lines are arranged crossing each other in a display region. A TFT (Thin Film Transistor) which constitutes a pixel is arranged near an intersection of each signal line and each scanning line. Moreover, a driver circuit connected to the plurality of scanning lines is provided on the glass substrate.
When the TFT is formed using poly-silicon, the driver circuit can be formed simultaneously with the TFT using the poly-silicon. Furthermore, it is not necessary to lay out the scanning lines on a frame region of the glass substrate. Therefore, in the liquid crystal display device with the TFT formed of the poly-silicon, the frame region hardly expands even if the number of pixels of the liquid crystal display device increases.
By the way, the screen size of the liquid crystal display device becomes large for a cell phone unit use, and the number of pixels tends to increase every year. Since an occupancy area of the driver circuit for each scanning line is decided, when the number of pixels increases and a pixel pitch becomes narrow, the lay-out width of the driver circuit with respect to the pixel pitch expands relatively. However, since portability is requested in the cell phone unit, the cell phone unit has a problem that the lateral width of the substrate cannot be increased.
Then, it is thought to arrange the above-mentioned driver circuit by dividing into two or three driver circuits on the both sides of the screen. However, it is necessary to provide mutually different synchronization signals to the respective driver circuits in this case. However, since it is difficult to generate two or three kinds of synchronization signals in the conventional driver circuit, it is necessary to newly develop the driver circuit (integrated circuit) which can generate two or three kinds of synchronization signals, and as a consequence, which causes the raising of a manufacturing cost, and further, the raising of a product price.


A heads up display system includes a computer that is programmed to receive data from one or more sources in a vehicle. The computer is further programmed to identify respective subsets of the data to be provided to respective ones of a plurality of display devices, and to provide the respective subsets of the data to the respective display devices.

Vehicle drivers can experience difficulty in changing a focus point from a roadway to a vehicle display, e.g., as a driver ages the time to change a focus point of the driver's eyes (the accommodation time) generally increases. An accommodation time becomes especially noticeable and bothersome when a driver needs to glance between the road and a vehicle instrument cluster. Moreover, for some drivers it may even become impossible to focus on an instrument cluster without using reading glasses or bi-focal glasses.
One solution to problems caused by accommodation time requirements has been to implement some type of heads-up-display (display device) that has the ability to form images that appear at some distance from the driver, thus reducing or substantially eliminating the accommodation time. Unfortunately, present display devices suffer from limitations in their abilities to display virtual images, both in a number of virtual images and in locations at which virtual images can be displayed in a vehicle.


A footwear sole structure is provided herein comprising a sole including a heel portion and a forefoot portion and at least one pivot point. Each pivot point is disposed on one of the heel portion and the forefoot portion, and is smaller, in coefficient of friction, than the sole.

Footwear, such as shoes, designed for dancing, have been proposed. This includes footwear configured for pivoting. Such footwear typically includes a pivot point disposed on a ball portion of a foot.
However, the inventor has recognized that such existing footwear is not functional for a variety of reasons. For example, soles of such footwear may be designed for use on a dance floor, and may be too delicate for use on the street. Further, pivot points integrated into such soles may not be functional if they are flush with the sole. Further, where shoes are designed for use on the street, the sole material, including the tread and the pivot point, may generate too much grip for effective use of the pivot point. Therefore, the inventor has recognized that there is a need to solve at least one of these problems.
The description provided in the background section should not be assumed to be prior art merely because it is mentioned in or associated with the background section. The background section may include information that describes one or more aspects of the subject technology.


A method and apparatus for machining of bores in workpieces is described, where a honing tool, covered with an abrasive material coating and radially pressed against the wall of the bore, simultaneously performs a rotational motion and an axial reciprocal motion. In addition to the reciprocal and rotational motions, the honing tool performs a high-frequency, short-stroke self-oscillation, which is excited by ultrasonic oscillation in the range of 16 to 40 kHz.

An apparatus of this type is known from an article entitled "Frequenz-Honen fur hohe Abtragraten" [Frequency Honing to Attain High Rates of Removal] in the magazine Werkstatt und Betrieb [Shop and Factory] 118, 1985 (7), pp. 393 to 395 (in particular see p. 394, item 4.1). In the apparatus disclosed, an oscillating relative motion is superimposed on the basic motion of the honing operation, consisting of a rotary motion and an axial reciprocating motion. By means of this motion, an increase in the cutting speed (during the forward stroke) and automatic sharpening of the honing stones (during the backward stroke) is achieved. The oscillation is generated by two hydraulic cylinders. Although more precise information is not available from the article, it can be concluded from this article that the third motion component is a motion with a frequency of at most some 100 Hz. In this case the honing stones are hydro-mechanically pressed on under constant pressure.
A method called "resonant honing" is known from U.S. Pat. No. 2,939,250, which operates with a honing tool the honing bars of which are covered with a coating of abrasive material and are displaceable in a radial direction in that their oblique feed surfaces cooperate with correspondingly oblique feed surfaces of a feed bar. The feed bar is subjected to an oscillating electromagnetic field by means of a coil surrounding it which, as a result of a magnetostriction leads to corresponding periodic shortening or lengthening of the feed bar. Corresponding radial back-and-forth motions of the honing bars via the recited adjustment mechanism are a result of this oscillation. A second exemplary embodiment described in the same reference generates an oscillation between the inner surface of the bore and the stones of the abrasive material coating of the tool by setting the platform on which the workpiece has been fastened into rapid up and down motions. For this purpose the platform has been provided with an oscillation-generating device having a coil excited by an electromagnetic oscillation. In both variants of U.S. Pat. No. 2,939,250, this oscillation is intended to result in the break-down of abrasive grains which have become dull, and thus in an automatic sharpening of the abrasive coating. No information as to frequency is provided; based on the mechanical arrangement, however, it can be assumed that in this case, too, it lies somewhere around 100 Hz. The adjustment device (FIG. 2) or the platform with the workpiece (FIG. 3) illustrated would be too sluggish for higher frequencies.
A method, also with the aim of continuous automatic sharpening of the abrasive coating, is described in U.S. Pat. No. 2,939,251, where the workpiece (see FIG. 2) or the tool (see FIG. 9) is given a third oscillation which lies in the range of 20000 to 100000 Hz, preferably above the audible range, to prevent annoying surrounding noise. In this case, too, there are electromagnetically excited oscillations which are generated by means of coils moving the support for the tool or the workpiece appropriately back and forth. However, the support for the tool or the workpiece does not undergo self-oscillation, it only acts as a rigid means for the transfer of oscillations from the oscillation generator to the tool or the workpiece.
In the course of so-called super-finishing (also: outside honing) in continuous operation, the rotational-symmetrical workpieces are given a rotational motion and on the exterior surface a honing stone is placed, which is given a high-frequency oscillating motion parallel to the rotational axis of the workpiece (see German Patent Publication DE 35 33 082 A1). As a rule the oscillations used in this case have frequencies of up to 3000 oscillations per minute, i.e. of up to 50 Hz. For improving the abrasion of the workpiece it was attempted by means of the method according to the cited reference to proceed in steps and to let the super-finishing stone spark out between the individual steps, each time after a forced feed path.
In connection with super-finishing, i.e. machining the exterior surfaces of rotation-symmetrical workpieces, it has also already been attempted to use ultrasonic waves for cleaning the honing stones (see German Published, Examined Patent Application DE-AS 24 35 848). In this case, however, the ultrasonic oscillation is not forced on the tool, instead it is sprayed via a rinsing liquid as the medium into the surface between the tool and the workpiece in order to increase the removal and flushing of dull or broken-off abrasive grains.
So-called "ultrasonic eroding" does not relate technologically to machining of the interior surfaces of bores, but to drilling of bores in general by means of ultrasonic-generating machining heads. This method has already been combined with drills (see U.S. Pat. Nos. 3,614,484 and 4,828,052). By means of this method it was possible to drill bores into materials which are too hard for normal drilling. However, this does not pertain to finishing of the interior surfaces of already drilled bores.

Method and apparatus for shaping the interior surfaces of bores


An OLED area illumination apparatus, comprising an OLED device, a variable power controller connected to the OLED device for providing variable power to the OLED device and responsive to a control signal, a feedback circuit for measuring the resistance of the OLED device and using the measurement signal for providing a control signal to control the variable power controller.

Solid-state lighting devices made of light-emitting diodes are increasingly useful for applications requiring robustness and long-life. Organic light-emitting diode solid-state lighting devices are of great interest because they may provide a light-emitting area rather than a point source of light (as is found in inorganic light-emitting diodes). This attribute of organic light-emitting diode lighting devices reduces the maximum heat of the device and facilitates efficient extraction of light from the diodes in a lighting fixture or lumiere.
Organic light emitting diodes (OLEDs) can be manufactured by depositing materials on a substrate and encapsulating them with a cover or layer. This process enables the creation of single, monolithic lighting elements on a single substrate. For example, FIG. 2 illustrates an OLED device suitable for lighting. Referring to FIG. 2, a prior-art OLED solid-state lighting device 10 may comprise a substrate 102 with a first electrode 104 deposited thereon. One or more layers of organic material 106 may be deposited on the first electrode 104, as is known in the prior art. A second electrode 108 is formed over the one or more layers of organic material 106. An encapsulating cover 110 protects the electrodes 104 and 108 and the one or more layers of organic material 106. The encapsulating cover 110 may also be a layer coated over the second electrode 108 (not shown). The electrodes 104 and 108 pass beneath the encapsulation layer 110 and are exposed as connectors to an external power source 112. The connectors may be arranged in a variety of configurations and can include, for example, insulating layers 114. In operation, when the external power source 112 supplies a voltage to the electrodes 104 and 108, a current passes through the one or more layers of organic material 106 and causes the organic materials to emit light.
OLED devices are subject to a variety of manufacturing difficulties and are also subject to changes in performance as the OLEDs are used. For example, it can be difficult to maintain a consistent performance from one device to another, even when the devices are manufactured on a common substrate or in a common process. Likewise, as is well known, OLED devices become less efficient over time and output less light with the same amount of power.
Since the brightness of an OLED lamp depends on the magnitude of the applied voltage, a variety of techniques have been used to compensate for aging by increasing the voltage applied to the lamp as the lamp ages. The simplest control is a dimmer, with which one manually adjusts the brightness of the lamp to suit one's taste. For EL (Electroluminescent) lamps powered from an AC power source, a dimmer is simply a potentiometer in series with the lamp. Most EL lamps are driven by an inverter powered by a battery. The inverter typically includes a switching circuit that produces a series of pulses which are coupled to the lamp. The switching circuit can be self-oscillating or driven. Dimming inverters are known in the art and typically use pulse width modulation to change the voltage across the EL lamp.
Both manufacturing variability and OLED aging have been addressed in the prior art. For example, U.S. Pat. No. 6,353,291 by Borgogno et al. entitled "Electroluminescent lamp controller" describes electronic sensing circuits that monitor multiple sized EL cells, referred to as a lamp, and compensate for variations in contrast between cells, while maintaining a fixed contrast between the luminance of the cells and the ambient lighting. In one embodiment, three separate feedback loops monitor the ambient lighting, cell-luminance, and frequency of the excitation voltage and make appropriate adjustments to an adjustable luminance reference. In another embodiment the circuit that drives the EL cells includes a timer and a microprocessor. The timer measures the elapsed time during which the EL display has been operating. The microprocessor adjusts the drive signal to the EL display to correct for aging, based on the elapsed time measured by the timer and an empirically-determined aging parameter. All these adjustments are accomplished while a microprocessor sequences through a large assortment of electroluminescent cells of various sizes.
In a related approach, U.S. Pat. No. 5,493,183 by Kimball entitled "Open loop brightness control for EL lamp" discloses an EL lamp characterized by non-linear brightness decay that is driven to constant brightness for the life of the lamp by an inverter controlled by a microprocessor. The microprocessor controls the inverter in accordance with a table containing data that is the inverse function of the non-linear brightness decay. The microprocessor tracks the total on-time of the EL lamp and selects the appropriate data from the table for driving the lamp. Control can be analog or digital. If control is analog, the selected data is coupled to a D/A converter which is coupled to the inverter. If control is digital, the selected data is coupled to a counter driving a pulse width modulator which is coupled to the inverter. In accordance with another aspect of the invention, an EL lamp is dimmed a precise amount based upon the data in the table and the EL lamp can be dimmed in unison with other lamp types, each lamp type having a table containing data for dimming. However, such designs require expensive controls (e.g. a microprocess) for tracking device use and providing corrective control.
Automatic brightness controls include optical feedback, in which a photocell monitors lamp brightness and varies the applied voltage to obtain a predetermined brightness, and analogue feedback, in which a lamp property, such as capacitance, is monitored to determine the applied voltage. U.S. Pat. No. 5,089,748 by Ihms entitled Photo-feedback Drive System discloses a system including optical feedback for maintaining the brightness of an EL lamp. U.S. Pat. No. 6,337,541 by Dickie et al. entitled "Electroluminescent lighting device" describes a supplementary lighting device with a replaceable electroluminescent light element. A control system is provided to boost the light intensity of the electroluminescent light element. A light sensor is provided which detects light emitted from the electroluminescent lighting element and inputs this information to the control system. The control system automatically adjusts the intensity of the electroluminescent lighting element according to a pre-set value and the information from the light sensor. This allows for the electroluminescent lighting element to maintain a constant output despite the ageing of the electroluminescent lighting element. The pre-set value for the intensity of the electroluminescent lighting element can be adjusted by a user-controlled dimmer. The dimmer varies the amount of light detected by the light sensor in order to increase or decrease the power provided by the control system to the electroluminescent lighting element.
Such a design requires an expensive optical sensor and the location of the sensor makes designing a display difficult because the sensor must be hidden and one must make separate connections to the sensor and to the lamp. Unless precision sensors are used, the part-to-part variability in sensors may cause unacceptable results. Moreover, such optical feedback designs require a large number of additional and expensive components and are subject to error from ambient light.
It is also important that lighting devices in common use by consumers be compatible with the existing lighting infrastructure, for example the common screw-type base known in the United States and the pin-type bayonet bases used in Europe. Moreover, the lighting devices must be readily and safely replaced by consumers at minimal cost.
In view of the foregoing, it is therefore an object of the invention to provide a low cost system for maintaining the brightness of an OLED lamp as it ages. A further object of the invention is to provide a control system that uses minimal additional and inexpensive components, and has a simple construction, low cost, and compatibility with the existing lighting infrastructure.

Variable power control for OLED area illumination


Method and apparatus for assembling steam turbines are provided. The method of assembling a steam turbine includes providing an annular outer member, providing an annular inner member, coupling a plurality of airfoils to the inner member with a plurality of generally radial fastener assemblies such that the plurality of airfoils extend substantially radially outward from the inner member, and coupling each of the plurality of airfoils to the outer member.

This invention relates generally to steam turbines, and more particularly, to methods and apparatus for assembling steam turbines.
At least some known steam turbines include a turbine configuration that includes a plurality of stages of diaphragms. Within at least some known turbines, the last few stages of diaphragms are called fillet fabrications that are constructed of an annular outer ring, an annular inner ring, and a plurality of circumferentially-spaced airfoils, partitions, and/or nozzles, extending there-between. To facilitate enhancing the structural integrity of such diaphragms, the airfoils are welded to the inner and outer rings. More specifically, to facilitate achieving a pre-determined weld strength, known fillet fabrications include a large weld fillet at the interface defined between the airfoil and the ring.
During the fabrication of at least some known fillet fabrications, a flowpath surface of the inner ring and outer ring are first scribed with lines facilitate positioning the airfoils prior to the individual airfoils being welded in position. However, because known airfoils are typically heavy and are difficult to maneuver, the welding process may be a time-consuming and laborious task. In other known fabrication methods, a complex fixture is used to facilitate aligning and holding the airfoils during welding. However, known fixtures are expensive. Moreover, within each method of fabrication, weld distortion may occur due to local heating and shrinkage of the weld material during fabrication of the diaphragm. As a result, often extensive labor-adjustments and/or machining of the assembled diaphragm is necessary to ensure that pre-determined tolerances and throat limitations defined between circumferentially-adjacent airfoils are satisfied. Additionally, distorted airfoils or rings generally can not fully obtain desired tolerances, such that stage performance may be compromised.

Methods and apparatus for assembling steam turbines


A compensator device for manipulating and reducing the effects of firearm muzzle lift and a lower receiver for manipulating environmental effects on firearms and firearm operators.

In firearm operations, various factors and phenomena affect use of firearms in a negative way. When a projectile is propelled out of a firearm, gases expand and various phenomena are produced. One phenomenon is referred to as recoil. Recoil is typically produced by gas expanding against an inner wall located near a rear end of the farm, producing a rearward force on the firearm which in turn produces a force on the firearm operator or the mounting mechanism on which the firearm is deployed.
Another phenomenon that propelling a projectile out of a firearm may produce is muzzle lift. Muzzle lift is typically produced by expanding gases exerting forces on various parts of a firearm causing the forward end of the firearm, typically referred to as the muzzle, to lift with respect to its position before the projectile was launched. When a firearm requires more energy to propel a projectile or when projectiles are launched in rapid succession, the effects of muzzle lift are typically intensified. Muzzle lift can affect the accuracy of a firearm because it becomes more difficult to keep the muzzle aimed at a single vertical location throughout multiple firings. The muzzle may rise to the extent that the firearm blocks an operator's sight or a target the operator was aiming at. An operator's sight may further be blocked by gases exiting near a forward end of the firearm. Muzzle lift may fatigue an operator as a result of the operator making constant efforts to keep the muzzle at a single vertical location after each projectile firing.
Expanding gases may also carry agents such as dust and gunpowder to various parts of the firearm, resulting in maintenance problems in terms of both having to take apart the firearm to clean more frequently and causing parts to wear out or fail more quickly. One example is when expanding gases cause dust or gunpowder to enter the threads of a firearm part, causing the part to wear out or the operator to disassemble and clean the part sooner than expected. Such phenomena not only interfere with the effective and efficient use of a firearm but also cause an operator or manufacturer to alter desired firearm design and specifications. For example, muzzle lift effects may cause an operator to dispose more mass along the barrel of a firearm causing increased weight, undesirable weight distribution, or increased cost.
Depending on what environment a firearm is in, conditions may hamper the effective use of the firearm. Conditions may in certain circumstances be a matter of self-preservation for a firearm operator.
In situations where a firearm or firearm operator is spatially restricted it becomes more difficult for the operator to effectively use and maneuver the firearm. The operator may find it more difficult in terms of how quickly and comfortably the operator can raise or lower the firearm. The weight of the firearm and distribution of such weight may increase the difficulty of handling a firearm. An operator may have to locate a support point along the barrel, thereby causing discomfort or a need for support components. Depending on firearm design and firearm surroundings, an operator will often have to support the firearm at a location near the lower receiver, causing operator discomfort or an increased probability of interfering with an installed magazine by displacing the magazine and risking malfunction. Such diverse support requirements sometimes require additional firearm components, possibly resulting in increased cost and firearm weight. The increased weight may lead to discomfort or fatigue for the operator or support mechanism.
Operational conditions may require an operator to exchange the magazine in a lower receiver under less than ideal circumstances in order to reload the firearm. An operator may have to exchange the magazine using only one exchange mechanism, such as an arm, or exchange the magazine without being able to see the firearm which carries with it increased difficulty and possibly increased reload time. Such circumstances may also cause an operator to dispose a magazine in a firearm so that the firearm malfunctions or otherwise interferes with operational efficiency.
An operator often will need to place more than one support point on the firearm in order to effectively and comfortable operate it. In certain situations, firearm design will require an operator to remove one support point from the firearm, such as to retrieve or display an object from a location not on the firearm. Removing a support point can interfere with firearm operations in numerous ways, including distracting the operator and displacing the muzzle of a firearm from a target.
The trigger of a firearm is essential to safe and effective firearm operations. However, certain operational conditions cause a trigger guard to interfere with effective use of a firearm. Certain trigger guards do not leave enough room for the trigger to be operated with precision when the operator is wearing gloves or has large fingers. Other trigger guards also require multiple components that result in increased assembly time, increased cleaning time, or increased cost for a firearm manufacture or operator. Many trigger guards, which are constructed of breakable plastic material, or attached with thin and breakable pins, may break or become dislodged, thereby exposing the trigger and increasing the risk of accidental discharge of the firearm.
Therefore, it is desirable to provide a lower receiver device for firearm operations that remedies or prevents effects resulting from the various operational conditions a firearm will encounter throughout its life.

Apparatus and method for firearm operations


A mobile Voice-over-Internet-Protocol (VoIP) phone communication system and method allows users to make mobile communication via mobile VoIP phones. A local mobile VoIP server is established in at least one specific communication zone and at least a central mobile VoIP server for coordinating the local mobile VoIP server in each zone is established. The mobile VoIP phone logins to the local mobile VoIP server in a specific communication zone to which the mobile VoIP phone enters, so the local mobile VoIP server identifies the mobile VoIP server in the zone and stores identification information of the identified mobile VoIP phone. If the mobile VoIP phone moves from a first specific communication zone to a second specific communication zone, the identification information of the mobile VoIP phone is recorded in the local mobile VoIP server in the second specific communication zone and the local mobile VoIP server transmits the identification information to a central mobile VoIP server, such that the central mobile VoIP server stores the identification information.

VoIP (Voice-Over-Internet-Protocol) offers a revolutionary way of communication that uses Internet to transfer voices in order to provide conversation over two (or more than two) parties. As technology evolves and Internet in applications of everyday life is more and more pervasive, transmitting voice data using this network backbone and its special Internet Protocol (IP) is not an issue anymore.
In addition, with the pervading of Internet and reduction of relevant cost, acquiring an VoIP phone becomes easier. In Taiwan, since the communication cost over Internet is typically three to five times cheaper than that of using a traditional telephone line, VoIP phone is the best option for saving cost for companies, families and individuals, especially when making long-distance calls.
However, voice quality of the VoIP phones is a technical bottleneck. Since the audio signal of the VoIP phones is compressed, its communication quality depends on the audio encoding/decoding scheme used. The higher the compression ratio, the less bandwidth is required, but the audio quality is compromised such that the quality is not as clear as that of a traditional phone. As a result, notwithstanding the cost of VoIP phone being much cheaper than a traditional phone, VoIP phone lacks a soaring market growth. In light of this, International Telecommunication Union (ITU) has set forth G.723.1 and G.729A standards that provides improvement of the communication quality for VoIP phones. Consequently, the number of people using VoIP phones in recent years has experienced a substantial growth. The VoIP phone market all over the world is increasing. "Financial Times" in British has reported that according to the estimation of a research institute In-Stat/MDR the number of people using the VoIP phones in the U.S. will quickly increase from 0.38 million this year to 4 millions in year local mobile VoIP server 2007.
Nonetheless, a bottleneck in the development of the VoIP phones is still present. Although the VoIP phones offer the possibility of transmission over computer-to-computer, computer-to-phone and phone-to-phone, it is still not capable of providing mobile communication, which greatly limits its popularity in today's world where mobile communication is being pursued.

Mobile VoIP phone communication system and method having a dialing process that utilizes a local mobile VoIP server in the same zone as a calling mobile VoIP phone

Inventec Multimedia & Telecom Corporation


The optical encoder includes a scale provided with a periodic pattern in which an optical portion is periodically formed with a first period in a first direction, and a light receiver movable relatively with the scale in the first direction and photoelectrically converts a detection light from a light source and then passing through the optical portions. The optical portion periodically has a pattern, which is formed by pattern portions mutually adjacent in a second direction orthogonal to the first direction and mutually shifted in the first direction, in the second direction with a second period of t. A width w of the light source in the second direction satisfies w=(a+b)/b·nt where n represents a natural number, and a:b represents a ratio of a distance from the light source to the periodic pattern and a distance from the periodic pattern to the light receiver.

1. Field of the Invention
The present invention relates to an optical encoder that optically reads a periodic pattern provided on a scale to output, a signal corresponding to the periodic pattern.
2. Description of the Related Art
Optical encoders are constituted by a scale provided with a periodic pattern and a sensor movable relatively with the scale. The sensor as a light receiver photoelectrically converts a detection light emitted from a light source and then passing through optical portions that reflects or transmits the defection light to output a signal (hereinafter referred to as "a periodic signal") having a change period corresponding to the periodic pattern. Use of the periodic signal enables detection of a relative movement amount (or a relative position) of the scale and the sensor and detection of an absolute position of one of the scale and the sensor. Furthermore, interpolation of the periodic signal enables position detection with, a finer resolution than a period of the periodic pattern. The period means a spatial period or a cycle length.
However, the periodic signal contains higher-order components that are integral multiple periodic components of the period of the periodic pattern, which makes it impossible to ignore errors caused by the high-order components when number of interpolation is increased. Japanese Patent Laid-Open No. 03-048122 discloses an optical, encoder that reduces higher-order components included in a periodic signal. In this encoder, a reference pattern and another pattern having a phase shifted from that of the reference pattern toy ⅙ are provided mutually adjacently in a direction orthogonal, to a direction (hereinafter referred to as "a period direction") along the period of the periodic pattern. The encoder removes a third-order component as the higher-order component by causing a light receiver to collectively receive lights transmitted through these two patterns.
However, in general optical encoders, the scale and the sensor are attached to separate members constituting an apparatus in which the encoder is provided, and thus mechanical backlash of these members may relatively displace the scale and the sensor in a direction orthogonal to the period direction of the periodic pattern. In the encoder disclosed in Japanese Patent Laid-Open No, 03-048122, a relative displacement, of the scale and the light receiver in the direction orthogonal to the period direction changes a ratio of the above-mentioned two patterns in a detection area by the light receiver on the scale. Such change of the ratio of the two patterns results in change of a phase of a fundamental wave of the periodic signal or decrease of the higher-order component removal effect, which makes it impossible to position detection with good accuracy.

Optical encoder and apparatus including the same


A replaceable needle assembly is provided for a retractable syringe comprising a barrel and a plunger, whereby the retractable needle can be replaced by a user without affecting the retraction mechanism. A mounting member is removably mountable to the barrel by way of a screw-thread connection and a needle mount is removably coupled to the mounting member. A needle is mounted to the needle mount. The barrel comprises a needle mount retainer that comprises a plurality of fingers that engage the retractable needle mount to prevent inadvertent retraction. The plunger comprises a collapsible seal which maximizes the efficiency of fluid delivery prior to the plunger engaging the retractable needle mount for retraction. An initially compressed spring decompresses to drive retraction of the plunger and the engaged needle mount. A lock formed between the plunger and barrel prevents further use of the plunger after retraction.

The practice of sharing syringes without adequate sterilization between successive users is a major contributor to the transfer of Human Immunodeficiency Virus (HIV) and Hepatitis C with subsequent severe repercussions for the sufferer and at a high cost to society for supporting and providing medical attention to sufferers. Further problems arise for health professionals administering medicines to infected individuals, where accidental needle stick injury by a used syringe can lead to infection.
In response to this problem, syringes have been developed which provide a needle sheathing mechanism and/or a needle retraction mechanism to prevent re-use and/or needle stick injury.
However, many such syringes have fixed needles or highly specialized needle assemblies that are not amenable to replacing needles which have been bent or burred or for allowing a user to select alternative needle sizes for filling and injection.

Clinical syringe with replaceable retractable needle


An optical time shifter and routing system having high efficiency switched gratings to form optical time delay and routing networks. This system also includes a unique passive noise suppression device that can be used in multiple channel optical systems such as time shifters and routers to increase channel isolation and reduce crosstalk. The latter noise suppression devices are applicable broadly to the free-space time shifters as well as to other time shifters.

With the advent of substanial new uses for electro/optic systems, there exists a greater need to effectively control the passage of electro-optic signals, both in their direction and time. This is especially true in phased array systems, although, it should be realized that this is just one of numerous electro-optic systems which require the use of an optical time shifting and routing mechanism.
Phased array systems are generally made up of arrays of many relatively isotropic radiators or emitters, spaced for example by half their radiating wavelength, that are each driven coherently but with a relative phase (or time) shift among individual elements or among subarrays of elements. Controlling this phase shift across the array of radiators permits the array to form a beam that is strongly peaked in the far-field. Using this well established technique, the direction of the beam can be steered electronically (much faster than is possible mechanically) by controlling the phase shifts. Further, the angular width of the beam decreases as the lateral extent of the array increases--driving the need for extensive arrays (e.g., in excess of one hundred wavelengths lateral extent) and thus for large numbers of elements. Even with subarraying techniques in which subsets of radiators are ganged to a common shifter so as to reduce the number of phase shifters required, the requirement for rapidly introducing phase or time delays into many parallel microwave channels forms a major technological challenge. It would therefore be highly desirable to provide digital time or phase shifting of signals for each emitter in a fast, accurate, compact, lightweight, inexpensive system while introducing minimal insertion losses and negligible spurious noise signals from scatter, reflections, and imperfect switch purity.
There are many practical barriers to implementing time delay networks directly in the microwave bands. These include difficulties such as: the power splitters used in such networks are large; the cables or waveguides used at microwave frequencies are bulky; the networks tend to be lossy; and dispersion of these delay lines makes the use of multiple bands difficult. Photonic technologies can be applied to this problem, for example, by converting the microwave signals to modulation on optical carriers, introducing the required delays optically, and then converting back into the microwave regime. This type of translation scheme permits the use of optical devices and techniques in phase shifting that are superior to those operating directly in the microwave regime.
For example, optical time delay networks can potentially be light weight, compact, and insensitive to electromagnetic crosstalk and interference. They can provide very long delays when required. Further, the dispersion effects are greatly reduced and multiple microwave bands can use the same delay network. Still, the advantages of using optical phase or time shifting must outweigh the overhead associated with converting to and from the optical regime.
Another technological challenge associated with driving phased array antennas arises in systems utilizing large bandwidth signals. When beam forming is accomplished by introducing phase delays (rather than time delays), large bandwidths cause the direction of the beam to detune from its desired direction. Since very large bandwidths are required for communication and identification of targets and tracking (as opposed to many searching tasks), true time delay beam forming networks are also important in high performance phased array systems.
In addition to the requirement for true time delay in beam forming for future phased array radar systems that utilize large bandwidth signals, it has been shown that time delay networks are needed with 1) low insertion loss (to reduce amplifier gain and resulting nonlinearities with strong signals); 2) low crosstalk among delay channels (to reduce amplitude and phase distortions in the resulting signal); and 3) low spurious signal generation (to reduce the formation of unwanted lobes in the array pattern). These additional requirements augment the technological challenge in future beam forming networks.
Recently there has been much attention to the application of photonic time delay networks for addressing the phased array beam forming problem. There are many openings for the application of optical approaches in radar systems, and the concept of optical beam forming with time delay networks has been physically demonstrated in W. Ng, A. A. Walston, G. L. Tangonan, J. J. Lee, I. L. Newberg, and N. Bernstein, "The First Demonstration of an Optically Steered Microwave Phased Array Antenna Using True-Time-Delay," Journal of Lightwave Technology, 9, 1124 (1991). The bulk of the optical approaches, however, have been directed at switching and delaying the optical carrier using guided waves such as in optical fibers or planar waveguides. Many of these techniques use combinations of integrated optical switches and guided wave delay lines.
Other approaches for optically introducing time or phase shifts which have difficiencies associated therewith include the use of heterodyning and coherent techniques and the use of segmented mirror spatial light modulators and polarization routing through prisms in free space.
It is quite apparent there is still much room for advancement in these prior approaches, particularly with respect to losses, complexity, crosstalk, switch isolation, compactness and multiple reflection suppression.
It is therefore an object of this invention to provide an optical time shifter and routing system which incorporates therein a free-space switching technique.
It is a further object of this invention provide an optical time shifter and routing system which has superior switch isolation, multiple reflection and crosstalk suppression; less complexity and lower insertion loss; and less stringent wavelength tolerances than time shifting systems of the past.
It is another object of this invention provide an optical time shifter and routing system which is extremely compact.
It is still another object of this invention provide an optical time shifter and routing system which utilizes a series of switchable gratings therein.
It is still a further object of this invention provide an optical time shifter and routing system which incorporates saturable absorber noise suppressors therein.


Systems, methods, and computer-readable media are provided for utilizing distributed erasure encoding in a redundant array of independent disks (RAID) system. An example method can include generating a plurality of virtual redundant array of independent disk (vRAID) stripes, each of the plurality of vRAID stripes including a segment having a plurality of data, each of the plurality of data including metadata, the metadata including a checksum of a corresponding data of the plurality of data, distributing the segment of each of the plurality of vRAID stripes over a plurality of virtual nodes, mapping at least one of logical files, volumes, or objects to the plurality of data chunks and the at least one parity chunk of the plurality of vRAID stripes to avoid write-hole issues, and verifying data integrity of the corresponding data of the plurality of data using the checksum of the corresponding data.

Erasure coding (EC) is a method of transforming data (e.g., with k bits) with redundant information (e.g., with n-k bits) such that original data can be recovered from a subset of n bits. This method is commonly used for protecting data against one or more transmission or storage device failures. Erasure encoding is more space-efficient compared to other data protection schemes such as redundant array of independent disks 1 ("RAID1"), where data is simply mirrored across different storage devices. There are four common issues when implementing erasure encoding for data storage protection: 1) write-hole problems occur when an erasure-encoded stripe is partially written in an event of a power failure, e.g., rebuild of a subsequent disk failure may generate incorrect data; 2) negates the benefits of other space efficiency mechanisms such as compression, which generates variable length data that results in partial stripe writes; 3) poor partial write performance because of read-modify-write; and 4) rebuild performance.

Method and apparatus for distributed erasure encoding