A wireless communication system is constructed by autonomous distributed operation of communication stations without having a relation of a controlling station and controlled stations. In the wireless communication system, each communication station checks a state of time synchronization with a neighboring station, determines whether the time synchronization needs to be corrected, and carries out one of methods of surely performing a time synchronization correcting process and performing the correcting process with a predetermined probability when the time synchronization needs to be corrected.

The present invention relates to a wireless communication system, a wireless communication apparatus and a wireless communication method, and a computer program. The wireless communication system communicates with a plurality of radio stations with each other, such as a wireless LAN (Local Area Network) or the like. The present invention particularly relates to a wireless communication system, a wireless communication apparatus and a wireless communication method, and a computer program in which a wireless network is operated by direct communication (random access) between communication stations.
More particularly, the present invention relates to a wireless communication system, a wireless communication apparatus and a wireless communication method, and a computer program in which communication stations perform network operation on an autonomous distributed basis without having a relation of a control station and controlled stations. Particularly, the present invention relates to a wireless communication system, a wireless communication apparatus and a wireless communication method, and a computer program in which communication stations operating on an autonomous basis form an autonomous distributed wireless network without interfering with each other while maintaining synchronization with each other.
Standards for wireless networks include for example IEEE (The Institute of Electrical and Electronics Engineers) 802.11(see Non-Patent Document 1, for example), HiperLAN/2(see Non-Patent Document 2 and Non-Patent Document 3, for example), IEEE802.15.3, and Bluetooth communication. As to the IEEE802.11 standard, there are extension standards such as IEEE802.11a (see Non-Patent Document 4, for example), IEEE802.11b, IEEE802.11g, and the like for different wireless communication systems and different frequency bands being used, for example.
Generally, in order to form a local area network using radio technology, a method is used in which one apparatus serving as a control station referred to as an "access point" or a "coordinator" is provided within an area and a network is formed under centralized control of the control station.
In wireless networks having an access point disposed therein, an access control method based on band reservation is widely used in which when information is to be transmitted from a communication apparatus, first a band required to transmit the information is reserved at the access point to use a transmission path so as to prevent collision with information transmitted by another communication apparatus. Synchronous wireless communication in which communication apparatuses within a wireless network establish synchronization with each other is performed by disposing the access point.
However, when asynchronous communication is performed between communication apparatuses on a sender side and a receiver side in a wireless communication system having an access point, the wireless communication always needs to be performed via the access point, thus halving efficiency of use of a transmission path.
On the other hand, as another method for forming a wireless network, "ad hoc communication" has been devised in which terminals perform wireless communication with each other directly on an asynchronous basis. For a small-scale wireless network formed by a relatively small number of clients located in the vicinity of each other, ad hoc communication is considered suitable. The ad hoc communication enables arbitrary terminals to perform direct wireless communication, that is, random wireless communication with each other without using a specific access point.
An ad hoc type wireless communication system, which has no central control station, is suitable for forming a home network including household electric appliances, for example. An ad hoc network has for example a feature of resisting failure because routing is automatically changed even when one appliance fails or is turned off, and a feature of being able to transmit data to a relatively long distance while maintaining a high data rate by hopping a packet a plurality of times between mobile stations. Various developed examples of the ad hoc system are known (see Non-Patent Document 5, for example).
For example, IEEE802.11 networking in an IEEE802.11 wireless LAN system is based on a concept of a BSS (Basic Service Set). There are two kinds of BSS: a BSS defined by an "infrastructure mode" in which a master such as an access point (control station) or the like is present, and an IBSS (Independent BSS) defined by an "ad hoc mode" in which the BSS is formed by only a plurality of MTs (Mobile Terminals). In the latter ad hoc mode, the terminals perform peer-to-peer operation on an autonomous distributed basis without a control station being disposed. When a beacon transmission time comes, each terminal counts a random period. When no beacon is received from the other terminals before the period is ended, the terminal transmits a beacon.
Details of conventional wireless networking will be described in the following by taking IEEE802.11 as an example.
Infrastructure Mode
A BSS in the infrastructure mode requires an access point for performing coordination within a wireless communication system. Specifically, the access point groups stations within reach of radio waves in the vicinity of the own station as a BSS to form a so-called "cell" in a cellular system. A mobile station present in the vicinity of the access point is accommodated by the access point, and enters the network as a BSS member.
The access point transmits a control signal referred to as a beacon at appropriate time intervals. A mobile station that can receive the beacon recognizes presence of the access point in the vicinity, and then establishes connection with the access point.
The mobile station in the vicinity of the access point can receive the beacon, decode a TBTT field within the beacon, and recognize a next beacon transmission time. Therefore, in some cases (cases where reception is not required), the mobile station may turn off a receiver to be in a sleep state (to be described later) until a next TBTT or a TBTT after one or more TBTTs.
In the infrastructure mode, only the access point transmits a beacon in a predetermined frame cycle. On the other hand, mobile stations in the vicinity enter the network by receiving the beacon from the access point, and the mobile stations do not transmit a beacon. Incidentally, since the present invention mainly focuses on operating a network without intervention of a master control station such as an access point or the like and is thus not directly related to the infrastructure mode, further description of the infrastructure mode will not be given.
Ad Hoc Mode
IEEE802.11 operation in the other ad hoc mode will be described with reference to FIG. 27.
A plurality of mobile stations in an IBSS in the ad hoc mode negotiates with each other, and then autonomously defines the IBSS. After the IBSS is defined, the mobile station group sets TBTTs at regular intervals after negotiation. When each mobile station recognizes that a TBTT arrives by referring to a clock within the own station, and when the mobile station recognizes that no beacon is transmitted yet after a delay of a random time, the mobile station transmits a beacon.
FIG. 27 shows an example in which two mobile stations form an IBSS. In this case, either one of the mobile stations belonging to the IBSS transmits a beacon each time a TBTT arrives. There is a case of collision between beacons transmitted from the respective mobile stations.
The mobile stations in the IBSS may also go into a sleep state by turning off a transmitter-receiver (to be described later) as required.
Procedure for Transmission and Reception in IEEE802.11
It is generally known that a hidden terminal problem occurs in a wireless LAN network of an ad hoc environment. When communication is performed between specific communication stations, a hidden terminal is a communication station that can be heard by one communication station with which the communication is performed but cannot be heard by another communication station. Since hidden terminals cannot negotiate with each other, there can be a collision in transmission operation.
As a method for solving the hidden terminal problem, CSMA/CA based on an RTS/CTS procedure is known. IEEE802.11 employs this method.
CSMA (Carrier Sense Multiple Access with Collision Avoidance) is a connection system for performing multiple access on the basis of carrier detection. In wireless communication, it is difficult for a communication station to receive an information signal transmitted by the communication station itself. Therefore, by the CSMA/CA (Collision Avoidance) system rather than CSMA/CD (Collision Detection), the communication station checks that no information is transmitted from other communication apparatuses, and then starts transmitting information of the communication station, thus avoiding collision.
In the RTS/CTS system, a communication station as a data sender source transmits a transmission request packet RTS (Request To Send), and then starts transmitting data in response to an acknowledgement packet CTS (Clear To Send) from a communication station as a data transmission destination. Receiving at least one of the RTS and the CTS, a hidden terminal sets a transmission stop period of the own station for expected period to transmit data based on the RTS/CTS procedure to be performed, whereby collision can be avoided. A terminal hidden from a sender station receives a CTS and then sets a transmission stop period to avoid collision between data packets. A terminal hidden from a receiver station receives an RTS and then sets a transmission stop period to avoid collision between ACKs.
Procedure for Transmitting and Receiving Signal in Sleep State
In IEEE802.11 networking, a mobile station in an IBSS at the time of the ad hoc mode may also go into a sleep state by turning off a transmitter-receiver as required.
When the sleep mode is applied in the IBSS of IEEE802.11, a certain period of time from a TBTT is defined as an ATIM (Announcement Traffic Indication Message) window. For the time period of the ATIM window, all mobile stations belonging to the IBSS operate a receiver. During this time period, a mobile station operating in the sleep mode is basically capable of reception.
When each mobile station has information for a destination, the own station transmits an ATIM packet to the communication destination during the time period of the ATIM window, thereby notifying the receiver side that the own station has the information to be transmitted. The mobile station receiving the ATIM packet operates a receiver until reception from the station that transmitted the ATIM packet is ended.
FIG. 28 shows an example in which three mobile stations STA1, STA2, and STA3 are present in an IBSS. When a TBTT arrives, the mobile stations STA1, STA2, and STA3 each operate a back-off timer while monitoring a state of a medium for a random time. In the example shown in FIG. 28, the timer of the mobile station STA1 expires the earliest, and the mobile station STAL transmits a beacon. Since the mobile station STAL transmits the beacon, the mobile station STA2 and the mobile station STA3 receiving the beacon do not transmit a beacon.
In the example shown in FIG. 28, the mobile station STA1 has information for the mobile station STA2, and the mobile station STA2 has information for the mobile station STA3. In this case, after the beacon is transmitted and received, the mobile stations STA1 and STA2 each operate the back-off timer while monitoring a state of the medium for a random time again. In the example shown in FIG. 28, the timer of the mobile station STA2 expires earlier, and the mobile station STA2 transmits an ATIM message to the mobile station STA3. Receiving the ATIM message, the mobile station STA3 gives a feedback indicating the reception of the ATIM message to the mobile station STA2 by transmitting an ACK (Acknowledge) packet.
After the transmission of the ACK is completed, the mobile station STA1 further operates the back-off timer while monitoring a state of the medium for a random time. When the timer expires, the mobile station STA1 transmits an ATIM packet to the mobile station STA2. The mobile station STA2 gives a feedback to the mobile station STA1 by returning an ACK packet indicating the reception of the ATIM packet.
During an interval after the ATIM packets and the ACK packets are exchanged within an ATIM window, the mobile station STA3 operates a receiver to receive information from the mobile station STA2, and similarly the mobile station STA2 operates a receiver to receive information from the mobile station STA1.
After the end of the ATIM window, the mobile station STA1 and the mobile station STA2 having the information to be transmitted each operate the back-off timer while monitoring a state of the medium for a random time. In the example shown in FIG. 28, the timer of the mobile station STA2 expires earlier, and thus the mobile station STA2 first transmits the information to the mobile station STA3. After the transmission of the information is completed, the mobile station STA1 operates the back-off timer while monitoring a state of the medium for a random time again. When the timer expires, the mobile station STA1 transmits a packet to the mobile station STA2.
In the above-described procedure, a communication station receiving no ATIM packet within the ATIM window and a communication station having no information to be transmitted keep a transmitter-receiver turned off until a next TBTT to thereby reduce power consumption.
[Non-Patent Document 1]
International Standard ISO/IEC 8802-11: 1999 (E) ANSI/IEEE Std 802.11, 1999 Edition, Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications
[Non-Patent Document 2]
ETSI Standard ETSI TS 101 761-1 V1. 3. 1 Broadband Radio Access Networks (BRAN); HIPERLAN Type 2; Data Link Control (DLC) Layer; Part 1: Basic Data Transport Functions
[Non-Patent Document 3]
ETSI TS 101 761-2 V1. 3. 1 Broadband Radio Access Networks (BRAN) HIPERLAN Type 2; Data Link Control (DLC) Layer; Part 2: Radio Link Control (RLC) sublayer
[Non-Patent Document 4]
Supplement to IEEE Standard for Information technology—Telecommunications and information exchange between systems—Local and metropolitan area networks—Specific requirements—Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) specifications: High-speed Physical Layer in the 5 GHZ Band
[Non-Patent Document 5]
C. K. Tho, "Ad Hoc Mobile Wireless Network" (published by Prentice Hall PTR)
As described above, in a wireless communication system in which communication stations perform network operation on an autonomous distributed basis without having a relation of a control station and controlled stations, each communication station makes presence of the communication station itself known to the other communication stations in the neighborhood (that is, within a range of communication) by sending beacon information periodically on a channel, and notifies a network configuration. Since the communication station transmits a beacon at a start of a transmission frame cycle, the transmission frame cycle is defined by a beacon interval. Also, each communication station can detect a beacon signal transmitted from neighboring stations by performing scan operation on the channel for a period corresponding to the transmission frame cycle, and be informed of the network configuration (or enter the network) by decoding information described in the beacon.
In such a wireless communication system, each communication station needs to periodically send beacon information and manage beacon information as described above while maintaining time synchronization with the neighboring stations. Also, in an access method based on time synchronization in which the communication station reserves a band or sets a priority use period within a frame cycle, for example, it is very important for communication stations to maintain time synchronization with each other.
In many of conventional wireless communication systems requiring time synchronization, each communication station establishes time synchronization with a neighboring station through intervention of a control station, and thereby time synchronization can be established between communication stations present in the same network.
On the other hand, since a wireless communication system in which communication stations perform network operation on an autonomous distributed basis does not have a relation of a control station and controlled stations, a conventional method of establishing time synchronization cannot be applied to such a wireless communication system. For example, in the wireless communication system of the autonomous distributed type, a method is conceivable which temporarily defines a master-slave relation between communication stations and thus creates a communication station temporarily serving as a control station within the same network, whereby a conventional method is applied to establish time synchronization. However, processes for determining the master and the slave and for resetting the master when the master disappears from the network are complicated.
Since each communication station in ad hoc communication has a greater process load than in infrastructure communication performed via an access point or the like, further increase in the process load is not desirable. Thus, the autonomous distributed type communication system requires techniques that enable time synchronization to be established between communication stations by a relatively simple process.

Wireless communication system, wireless communication apparatus and wireless communication method, and computer program


An improved drum structure for a corrugated deck type rotary drum filter is provided that increases filter efficiency by eliminating transverse filtrate flow in the drain channels of the drum. Each drain channel is divided into sub-channels using at least one solid grid. The sub-channels drain into a single bucket associated with the drain channel. A drain slit is provided above each sub-channel in the corrugated material that covers the outer surface of the drum.

The invention relates in general to rotary drum filters. More specifically, the invention relates to an improved deck design that increases filter efficiency for corrugated deck type rotary drum filters.
Rotary drum filters are used in the pulp and paper industry to filter liquid out of pulp. The filters include a cylindrically shaped drum that is typically constructed of metallic and/or fiberglass materials. In operation, the drum is partially submerged in a vat containing a paper pulp stock. The outer surface of the drum acts a filtering medium or structure that passes liquid as the drum is rotated. Pulp is retained on, and subsequently removed from, the outer surface of the drum.
The drum includes a cylindrical shell that is supported on the inside by flyrings and is closed at each end by end supports. Longitudinal grids are installed perpendicular to the outside surface or deck of the shell in a predetermined spaced relationship. The longitudinal divider grids or rib elements extend along the entire length of the deck and define drain channels that empty into vacuum shut off sections, referred to as buckets, located at the periphery of the deck.
In some filters, referred to as "open channel filters", the longitudinal grids are covered with a backing wire that forms the outer surface of the drum. Liquid can pass through the spaces provided between the backing wire while pulp is retained on the surface of the wire. In other filters, referred to as "corrugated deck filters", an example of which is disclosed in U.S. Pat. No. 3,837,499, the contents of which is herein incorporated by reference, the longitudinal grids are covered with a corrugated material that forms the outer surface of the drum. The corrugated material includes drain slits that correspond to the drain channels. Each drain slit permits liquid to pass through the corrugated material to a single drain channel while pulp is retained on the surface of the corrugated material. It is an object of the present invention to increase the filtering efficiency of corrugated deck type rotary filters.

Drum structure for corrugated type rotary filters


The disclosed technology relates generally to a method and system for an improved lighting apparatus compatible with imaging small specimens for viewing or photographic purposes. In certain embodiments, the disclosed technology provides an apparatus for projecting light on specimens from opposing light sources at varying distances and angles. In certain embodiments, the apparatus includes an elongated stem that allows the light sources to be repositioned quickly, easily, and accurately. The elongated stem may be flexible and may be used in conjunction with a positioning system, such as a rack and pinion system, thereby allowing precise movement of the light sources.

Lighting is an art that when skillfully applied may enhance the color, shadow, and texture of images for viewing and photography. Special techniques are often needed for optimal results, particularly if images are magnified. For instance, certain image characteristics may be improved by aiming light on a given specimen from two or more lights sources simultaneously. Types of lighting sources are numerous; however advances in light-emitting diode (LED) technologies over the past decade have resulted in light sources with relatively low heat load, small size, and minimal energy requirements compared to many other lighting technologies. Subsequently, LEDs are a natural choice for enhanced imaging, particularly when multiple sources are prescribed.
Enhanced imaging may be fairly unpredictable for a given specimen and experimentation with specific placement of light sources is often required. Indeed, some image details are only revealed with careful adjustment to the intensity and angle of light. Depending on the features to be enhanced, light sources that are too intense may be made more distant or positioned obliquely for better results. Yet, oblique positioning will not always improve contrast. Instead desired clarity may require fairly concentrated direct, front or back lighting.
At the same time, direct and concentrated lighting may produce unwanted shadows, reflections, and glare. These and other artifacts from light that is overly intense can be minimized if the light is dimmed or diffused. Problems from too much light may also be corrected with shades, filters that help limit specific wavelengths, or with polarized lenses that can scatter and soften the light as required per application.
Imaging equipment incorporating features for experimenting with lighting adjustments are plentiful. Diffusers, reflectors, variable intensity light sources, and positioning adjustments are typically incorporated into light microscopes. Annular light rings are also combined to provide adjustable light quality from devices having multiple sources of light.
An example of a state of the art lighting device is found in U.S. Patent Publication No. 2011/0026113 of Paulus. The publication's disclosure describes a device incorporating a flexible and elastic reflector, moveable through different positions with respect to a sample placed on a microscope stage. The reflector houses multiple light sources in an annular arrangement and provides diffuse lighting at different distances and positions from the sample to the extent that the reflector is configurable.
Still, there is a need to further advance lighting for close imaging of small specimens. An apparatus with the capacity to position multiple light sources at varying distances and angles around specimens that also offers the operator the ability to independently adjust individual light sources would make illuminating specimens easier to optimize while providing easy access to staged specimens. In accordance with the present invention, related embodiments of a lighting apparatus and methods improve upon advantages of known devices.

System and apparatus for illuminating a specimen


An automatic gain control device includes an amplifier for a reception signal, a signal processing unit, a memory, and a control unit. The amplifier can set a gain. The signal processing unit extracts control data from an output from the amplifier and performs information processing for the data. The memory stores the gain setting value of the amplifier. The control unit controls the gain of the amplifier in accordance with a preset control algorithm. On the basis of the result obtained when the control unit computes a gain setting value stored in the memory in accordance with a preset algorithm, the control unit controls the gain of the amplifier in correspondence with operation of switching the frequency of a reception signal, which is accompanied by different frequency monitoring in the compressed mode by the signal processing unit. A radio communication terminal, a control method for an automatic gain control device, a control program for an automatic gain control device, an automatic gain control method, a radio communication system, and a radio communication method are also disclosed.

The present invention relates to an automatic gain control device for an amplifier capable of setting a gain, an automatic gain control method, a control program for an automatic gain control device, a radio communication terminal having an automatic control device, a radio communication system, and a radio communication method and, more particularly, to an automatic gain control device for an amplifier in the reception unit of a radio communication terminal which can switch the frequency of a reception signal in the compressed mode, an automatic gain control method, a control program for an automatic gain control device, a radio communication terminal having an automatic control device, a radio communication system, and a radio communication method.
In general, in a radio communication terminal such as a PHS, a cellular phone, an information terminal, e.g., a PC capable of wireless LAN connection, or a PDA, AGC (Automatic Gain Control) is performed to improve the precision in converting a reception signal (analog signal) into a digital signal.
In general, in a radio communication terminal, the reception signal received at the antenna must be converted into a digital signal. The reception signal is amplified by an amplifier, and then input to an ADC (Analog Digital Converter) which converts an analog signal into a digital signal. A processor or the like then, for example, extracts communication data and control data from the reception signal converted into a digital signal by the ADC and processes them. Information processing for the reception signal is performed by the processor or the like.
Since the resolution of the ADC is fixed, in order to convert an analog signal into a digital signal with high precision by using the limited resolution as much as possible, an input value to the ADC is preferably a value close to the maximum value in the range of input values (dynamic range). If, however, an input value to the ADC exceeds the dynamic range, proper measurement cannot be done. It is therefore also necessary for an input value to the ADC (an output from the amplifier on the input stage of the ADC) not to exceed the maximum value. On the other hand, the strength of a reception signal varies with changes in external environment.
In order to make the input amplitude of the ADC constant by absorbing changes in the strength of reception signals, the gain of the amplifier must be controlled. In this case, control to make the output of the amplifier capable of setting a gain value constant is called automatic gain control, and an automatic gain control device is a control device including an automatic gain control function.
The performance of an automatic gain control device has a great influence on the signal reception characteristics of an overall radio communication terminal. A high-performance automatic gain control device is indispensable to a high-performance radio communication terminal. The radio signal receiver of the radio communication terminal is exposed to abrupt changes in reception environment for radio signals depending on the movement of the terminal itself, the movement of an electric wave obstacle, and the specifications unique to a radio system. The automatic gain control device is required to stably hold a constant amplifier output even at the time of such a change in environment.
Various techniques concerning automatic gain control have currently been proposed.
First, there is available a technique concerning an AGC method in data communication using a frequency-hopping scheme (Japanese Patent Laid-Open No. 2000-236286). A data signal comprises a sync signal and information signal. AGC is operated during the reception of a sync signal, and stopped during the reception of an information signal. This makes it possible to prevent AGC from producing operation noise during the reception of an information signal, and hence prevents the transmission quality from being influenced by noise. After frequency hopping, the gain value of AGC which is stored before frequency hopping is used.
Second, there is available an AGC technique in the TDMA scheme (Japanese Patent Laid-Open No. 2002-076996). The TDMA scheme is a communication scheme of allocating time-divided data to users. If the number of users is small, there is a time-divided area (time slot) in which no data is transmitted. When AGC is operated in a time slot during which no data is transmitted, AGC operates in a direction to increase the degree of amplification because there is no input signal. When the radio receiver receives again a time slot in which data destined to it, the degree of amplification of AGC becomes inappropriate. For this reason, the radio receiver activates AGC only in a time slot in which data destined to itself is stored, but stops activating AGC in other times. The receiver uses the amplifier setting corresponding to the immediately preceding time slot. This makes it possible to obtain a stable amplifier output.
Third, there is available an AGC technique in the TDMA scheme (Japanese Patent No. 3064081). The predicted value of the gain value of AGC is calculated on the basis of the electric field strength of a specific signal in the immediately preceding time slot. Starting AGC by using the predicted value can perform control using a value close to an appropriate gain value from the beginning of AGC.
Fourth, there is available an AGC technique at the time of high-speed data communication in the CDMA/TDD scheme (Japanese Patent Laid-Open No. 2003-124759). The amount of variation in reception power (RSSI) of the immediately preceding time slot within the same frame is measured on the basis of the data rate, ISCP (Interference Signal Code Power) difference, and Doppler frequency. If the variation is large, the gain value of AGC is determined with reference to the RSSI of the immediately preceding time slot. If the variation is small, the gain value of AGC is determined with reference to the RSSI of a corresponding time slot in the immediately preceding frame. This makes it possible to perform control such that the gain value of AGC converges promptly even if a variation in RSSI is large.
Fifth, there is available an AGC technique based on positional information using a GPS system (Japanese Patent Laid-Open No. 2003-209477). A reception signal level is predicted from the distance between the current positional information of an AGC circuit which has been measured by using a GPS system at the start of communication and a known communication partner station. More specifically, a reception signal level is predicted on the basis of distance information, and the gain value of AGC which is suited to the reception signal level is predicted. ACG operation is stabilized by using the predicted optimal gain value of the amplifier.
The WCDMA standard technology includes the compressed mode as a mode unique to the system (e.g., "3GPP TS 25.212 V4.6.0, pp. 52-55" [online], Sep. 27, 2002, 3GPP, [retrieved Mar. 24, 2004], Internet <URL:
http://www.3gpp.org/ftp/Specs/html-info/25212.htm>:
"W-CDMA Mobile Communication Systems", edited by Keiji Tachikawa, Maruzen, Jun. 25, 2001, pp. 140-141). The compressed mode is a technique of preventing a decrease in data transmission amount due to a transmission gap, which is a time zone provided by a radio station at the time of transmission of a radio signal, in which no radio signal is transmitted, by transmitting radio signals obtained by compressing data before and after the transmission gap. In general, the compressed mode is assumed to be used for different frequency monitoring (measuring a radio signal having a frequency different from that of a radio signal received in a normal state) which is required when the radio communication terminal performs handover between stations with different frequencies or performs handover between radio systems with different frequencies.
Owing to demands for reductions in manufacturing cost, size, and the like, a radio receiver mounted in a radio communication terminal corresponds to only one frequency. Therefore, in order to receive radio signals with two different frequencies, the tuning frequency of the radio receiver must be changed.
In this case, consequently, when different frequency monitoring is to be performed by using the compressed mode, the radio communication terminal needs to switch the tuning frequency of the radio receiver. More specifically, the radio communication terminal must change the tuning frequency of the radio receiver from the initial frequency to a monitor target frequency at the occurrence of a transmission gap, and must monitor the electric field level, noise level, signal timing, and the like of the reception signal with the monitor target frequency. When the transmission gap is over, the radio communication terminal must change the tuning frequency of the radio receiver to the initial frequency. On the other hand, according to the WCDMA standard technology specifications, the minimum transmission gap in the compressed mode is very short, only 2 ms.
Although it depends on the specifications set by a management company for a WCDMA system, a radio communication terminal or network generally determines, on the basis of information obtained by a plurality of number of times of different frequency monitoring, whether or not the radio communication terminal performs handover.
The WCDMA standard technology requires a technique of switching the tuning frequency of a radio receiver a plurality of number of times within a short period of time. In addition, since only a short period of time is given for different frequency monitoring, and different frequency monitoring operation must be finished within the period of time, an automatic gain control device is required, which promptly converges to an optimal state and becomes stable immediately after switching of the tuning frequency of the radio receiver.
In the first to fifth techniques, however, no automatic gain control device is disclosed, which is based on the assumption that the tuning frequency of a radio receiver is switched a plurality of number of times in a short period of time. Furthermore, there is not disclosed any technique of performing automatic gain control by predictive computation suitable for the operation of switching the frequency of a reception signal.

Automatic gain control device, automatic gain control method, control program for automatic gain control device, radio communication terminal having automatic control device, radio communication system, and radio communication method


Several caliper accessories are provided that make a conventional caliper suitable for more sophisticated applications traditionally reserved for more expensive measurement devices. One of these accessories, a magnetic caliper mounting device, has a shallow scale-bar-mounting channel for receiving the scale bar of the caliper, a retainer adapted to releasably secure the scale bar of the caliper within the channel of the caliper mount, and a magnet associated with the caliper mount to secure the apparatus to a planar metal surface. Another accessory, a caliper jaw extender, is either incorporated into a magnetic caliper mounting device or provided as a spring pack accessory to a magnetic caliper mounting device. The caliper jaw extender has a spring-biased retractor that hooks onto a caliper's movable frame and biases the frame toward an extended position. Kits are also provided comprising various combinations of a conventional caliper and accessories.

Sliding calipers are handheld tools used to very precisely measure the distance between two symmetrically opposing sides. They are frequently used in checking or inspecting dimensions of parts and/or assemblies in metal, plastic, and woodworking fields. Conventional handheld sliding calipers are relatively inexpensive, but they are not suitable for many applications, such as the positioning of a sawtable fence, a milling machine travel table or spindle, or a metal lathe carriage, top slide, or tailstock. Stated another way, conventional handheld sliding calipers are generally not suitable as a generic machine positioning device.
Typically, precise movements of machining tools such as sawtable fences, milling machine tables, and metal lathe carriages are made by recording the relative positions noted by crude markings adjacent to a hand wheel or hand crank on the machine. Alternatively, precise single-application devices, designed specifically for a sawtable, milling machine, or metal lathe and typically costing hundreds of dollars, can be obtained and installed on these machines (or in some cases are purchased with the machine).
There is a need for an inexpensive, multiple-application accessory that can adapt a conventional handheld sliding caliper for use in making precise measurements on a wide variety of wood, metal, and plastic-working machines. There is also a need for an accessory for spring-biasing the movable frame of a conventional sliding caliper for two-way positioning detection.

Versatile caliper mounting and measurement accessory


A medicine administering device for nasal cavities, comprising a capsule holding section formed with a capsule containing powder-state medicine. An air supply section is connected to the lower end of the capsule holding section and formed with an air supply passage which is in communication with the capsule accommodating chamber. A branched passage section is connected to the upper end of the capsule holding section and has an air flow passage in communication with the capsule accommodating chamber. The air flow passage is bifurcated to form first and second outlet passage portions which are arranged to form a generally Y-shape. First and second medicine passages are formed such that air from the branched passage section flows therethrough to carry the medicine in the capsule into right-side and left-side nasal cavities of a patient. The first and second passages are respectively in communication with the first and second outlet passages of the branched passage section. First and second spraying holes are respectively in communication with the first and second medicine passages, the medicine from the first medicine passage and the medicine from the second medicine passage being sprayed respectively from the first and second spraying holes. The first and second spraying holes respectively have first and second axes which are separate from each other by a distance ranging from 12 to 25 mm.

1. Field of the Invention
This invention relates to improvements in a medicine administering device suitable for administering, for example, powder-state medicine into right-side and left-side nasal cavities of a patient.
2. Description of the Prior Art
In general, a method of curing by administering powder-state medicine through nasal cavities can be employed for a patient with nasal allergy, asthma or the like. In this curing method, an exclusive sprayer or medicine administering device is usually used in which a capsule filled with powder-state medicine is accommodated in a medicine accommodating chamber. The powder-state medicine inside the capsule is administered into the nasal cavities of the patient. An example of such a sprayer to be used for this curing method is disclosed in Japanese Patent Provisional Publication No. 59-34267.
This conventional sprayer includes a cylindrical body member which is formed with a capsule accommodating chamber in which a capsule containing powder-state medicine is accommodated. An air supply passage connects to the capsule accommodating chamber. The cylindrical body member is formed at its tip end portion with a medicine spraying hole through which the medicine in the capsule is sprayed into one of the nasal cavities of the patient. The medicine spraying hole is in communication with the capsule accommodating chamber. The capsule in the capsule accommodating chamber is perforated by a needle to be inserted through the medicine spraying hole.
With such a conventional sprayer, an operation for administering the powder-state medicine to the patient has been carried out as follows: First, the tip end portion (formed with the medicine spraying hole) of the cylindrical body member is inserted into one of the nasal cavities of the patient. Then, air is forced through the air supply passage into the capsule which has been perforated, so that the medicine in the capsule is carried through the medicine spraying hole into the nasal cavities of the patient. This operation is repeated alternately for the right-side and left-side nasal cavities of the patient in order to complete a medicine administration to the patient.
However, drawbacks have been encountered in the above conventional sprayer, in which administering the medicine to the patient is accomplished by alternately and repeatedly inserting the tip end section of the cylindrical body member into the right-side and left-side nasal cavities, and therefore it is difficult to supply the right-side and left-side nasal cavities with equal amounts of the medicine. This makes the medicine administering operation troublesome and requires a considerable time for the medicine administering operation.

Medicine administering device for nasal cavities


Embodiments of the present disclosure include a metal mesh structure and a method of fabrication thereof. The metal mesh structure includes a metal mesh formed on a substrate. The metal mesh is a 2D or 3D pattern of lines. The lines in the first and second set are characterized by a linewidth that is less than 2 microns. Such metal mesh structures are fabricated through rolling mask lithography. This abstract is provided to comply with rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

Photolithography fabrication methods have use in a wide variety of technological applications, including micro-scale and nano-scale fabrication of solar cells, LEDs, integrated circuits, MEMs devices, architectural glass, information displays, and more.
Roll-to-roll and roll-to-plate lithography methods typically use cylindrically shaped masks (e.g. molds, stamps, photomasks, etc.) to transfer desired patterns onto rigid or flexible substrates. A desired pattern can be transferred onto a substrate using, for example, imprinting methods (e.g. nanoimprint lithography), the selective transfer of materials (e.g. micro- or nano-contact printing, decal transfer lithography, etc.), or exposure methods (e.g. optical contact lithography, near field lithography, etc.). Some advanced types of such cylindrical masks use soft polymers as patterned layers laminated on a cylinder's outer surface. Unfortunately, lamination of a layer on a cylindrical surface creates a seam line where the edges of the lamination layer meet. This can create an undesirable image feature at the seam when the pattern is repeatably transferred to a substrate by using the cylindrical mask.
In addition to fabricating a mask having a seamless polymer layer, it would be desirable to fabricate polymer layers with smooth surfaces that are thick and uniform for use in subsequent rolling lithography fabrication methods.
It is within this context that the present invention arises.

Transparent metal mesh and method of manufacture


A system for producing dental moldings from blanks, having a machine tool for machining a blank, and a workpiece holder for securing the blank during machining. The machine tool has in this case a mount for the workpiece holder, and the workpiece holder has a shank region that can be inserted reversibly into the mount and in the inserted state can be secured in position in the mount. Furthermore, the system has a lever element, wherein the system is configured so that the lever element can be clamped between the mount on one side and the shank region on the other side to secure the shank region in position in the mount. With such clamping of the lever element, a particularly high clamping force can be produced, by way of which the shank region of the workpiece holder can be secured in position in the mount.

1. Field of the Invention
The invention relates to a system for producing dental mouldings from blanks, which has a machine tool for machining a blank, and also a workpiece holder for securing the blank during machining, wherein the machine tool has a mount for the workpiece holder, and wherein the workpiece holder has a shank region which can be inserted reversibly into the mount and in the inserted state can be secured in position in the mount.
2. Related Technology
Such a system is known from DE 10 2008 030 050 A1. With this system, the workpiece holder can be locked in a precise and reproducible manner in the mount of the machine tool. However, with this known system, it is possible—in particular in the case of blanks having a relatively long shape—for the clamping force with which the workpiece holder is secured in position in the mount to be limited so that a particular desired degree of precision in the machining of the blank can no longer be achieved.


A photographic printing paper support wherein one side of the raw paper is covered by a composition containing titanium oxide dispersed in polyethylene terephthalate resin or a mixture of polyethylene terephthalate and another resin, and the other side is covered by a composition containing calcium carbonate dispersed in polyethylene terephthalate resin or a mixture of polyethylene terephthalate with another resin, which can provide an excellent photographic paper having good water resistance, whightness and gloss is disclosed.

In photographic printing papers, the surface of the raw paper to be emulsion-coated is generally covered by a polyethylene or other polyolefin resin layer in which titanium oxide has been dispersed by kneading so as to improve water resistance and light reflectance. The titanium oxide in particular improves the whiteness of the paper, but it also tends to adversely affect the flatness of the paper.
In high gloss printing papers which are at present most highly valued, it is desired to improve the smoothness and gloss of the paper surface in order to improve the appearance of the image. Good results can be obtained by replacing the polyolefin by polyethylene terephthalate, but the paper suffered from the disadvantage that it curled with the passage of time.
The Inventors, after detailed studies, found that this tendency to curl is reduced by covering the surface of the raw paper to be emulsion-coated with a composition comprising a dispersion of titanium oxide in polyethylene terephthalate or in a resin having polyethylene terephthalate as its principal constituent.


Channel parameters for a magnetic readback channel are optimized by detecting a readback signal that is recorded on a magnetic medium. The readback signal contains a plurality of predetermined-length control fields. Each control field is arranged between two user data fields and contains at least one transition. At least one selected readback parameter, such as a frequency of a readback channel system clock, a gain of the readback channel, a equalization response of the readback signal, and/or an amplitude asymmetry of the readback channel, is optimized based on information contained in at least one control field.

1. Field of the Invention
The present invention relates to magnetic storage systems. More particularly, the present invention relates to a system and a method for reliably and accurately optimizing readback channel parameters of a magnetic storage system.
2. Description of the Related Art
FIG. 1 shows a functional block diagram of an exemplary magnetic tape recording system 100 that is connected to a host system 101. Magnetic tape recording system 100 includes read and write circuitry 102, a transducer 103, and a magnetic tape 104. Magnetic tape 104 is contained in a cartridge 105 and is taken up on a take-up reel 106 as magnetic tape 104 is transported past transducer 103. Binary data from host system 101 is stored on magnetic tape 104 by the write portion of read and write circuitry 102 selectively orienting magnetization in user data fields in the magnetic media of magnetic tape 104.
FIG. 2 shows a functional block diagram of the major functional blocks of an exemplary magnetic recording system 200 that is part of a magnetic tape recording system, such as magnetic tape recording system 100 shown in FIG. 1. Recording system 200 includes a write channel portion and a readback channel portion. The write channel portion includes a write formatter 202, a write driver 203 and a write head 204. During a recording operation, binary data 201 that is to be stored on a magnetic medium, such as magnetic tape 104, is input to write formatter 202. Write formatter 202, depending on the implementation, may add extra transitions between data transitions in a process referred to in the art as "write equalization." Write formatter 202 may also shift write pulses in time with respect to a write clock in a well-known manner, known in the art as "write precompensation," to improve recording performance of binary data 201. The output of write formatter 202 is applied to write driver 203, which, in turn is coupled to write head 204. Write head 204 writes binary data 201 onto the surface of magnetic media 205 in a well-known manner.
The readback channel portion of recording system 200 includes an analog readback channel 206 and a digital readback channel 210. Analog read channel 206 includes a read head 207, a read amplifier 208 and an Automatic Gain Control (AGC) system 209. Digital read channel 210 includes an Analog-to-Digital (A/D) converter 211, an equalizer filter system 212, a timing recovery system 213 and a data detector 214.
During a read operation, read head 207 detects stored data from magnetic media 205 and generates a readback signal that is amplified by read amplifier 208. The gain of read amplifier 208 is controlled by AGC system 209 and the output of AGC system 209 is input to digital readback channel 210. A/D converter 211 digitizes the output of AGC system 209. The output of AID converter 211 passes through equalizer filter system 212 and timing recovery system 213 before being applied to data detector 214. Data Detector 214 outputs the stored binary data 215 that was detected by read head 207 as the readback signal.
The task of the readback channel portion of recording system 200 is to properly decode the written data from the readback signal in the presence of a number of impairments, such as noise, variations in the media velocity, and variations of the head/media transfer function. Variations in the media velocity require that the clock of the readback system be continuously synchronized with the bits written on the magnetic medium by frequent updates to the period and phase of the readback system clock using an error signal that is based on the random data contained in the user data fields. For synchronous-sampling-type systems, the timing recovery feedback loop synchronizes the clock of the analog-to-digital converter. See, for example, R. D. Cideciyan et al., "A PRML System for Digital Magnetic Recording," IEEE Journal on Selected Areas in Communications, Vol. 10, No. 1, pp. 38–56, (1992). In asynchronous-sampling-type systems, the timing recovery feedback loop adjusts the phase of the synchronous sample interpolator. See, for example, U.S. Pat. No. 6,084,924 to C.M. Melas.
Variations in the head/media transfer function require repeated updating of many of the readback channel parameters. For example, the gain of read amplifier 208 must be continuously adjusted to compensate for variations in the head/media spacing, defects on the media surface or in the media itself, and variations in the signal amplitude. Additionally, the overall gain through the readback channel is constantly adjusted by an AGC operation that is performed in the analog domain, such as by AGC system 209, and in the digital domain within digital readback channel 210 using data decisions (not shown). AGC system 209 is a variable gain block that ensures that the amplitude of the signal envelope of the readback stays within prescribed boundaries. The gain control provided by AGC system 209 is conventionally determined by measuring the maximum value of the readback signal within a defined time window and then appropriately adjusting the maximum value to be within the prescribed boundaries. A conventional AGC block for a readback channel operates on the assumption that the random user data signal contains some isolated transitions having the maximum voltage swing. To ensure that this assumption is true, the random user data is conventionally encoded before being written to the magnetic medium. The AGC function of digital readback channel 210 receives an error signal from a data estimator (not shown in FIG. 2) that is the difference between a target signal value, received from the data estimator, and the actual value. The data estimator for the AGC and the timing loops is usually located between the timing recovery and the data detector.
Variations in the head/media transfer function also gives rise to a need for adaptive equalization, which is the process of changing or "adapting" the coefficients of equalizer filter system 212 which shape the readback channel transfer response to be a prescribed transfer function. The most common conventional adaptive equalization techniques utilize a Minimum Mean Square Error (MMSE) approach for continuously updating the coefficients of equalizer filter system 212. The adaptation is calculated based on an ideal, or target, sample value output of a data estimator and a comparison of the ideal sample value with a detected value. A data estimator can have many errors, and to ensure stability, equalizer adaptation is done very slowly using small updates, resulting in a slow convergence of a set of equalizer coefficients. Large levels of noise, however, can cause the adaptation algorithm to diverge.
All of the abovementioned channel parameter updates are conventionally based on the readback signal corresponding to the random user data stored on the magnetic medium as the readback signal is detected by the read head. Accordingly, the random data is estimated using a fast method and the estimates are used for setting the various control loops, such as timing recovery, AGC control and the adaptive equalization. When a fast estimation technique, such as a slicer, is used, very little noise can be tolerated before errors occur. When too many errors occur during the estimation process, the various control loops can become unstable, especially the timing control loop, resulting in very large blocks of errors. More reliable techniques of estimating the data introduce too much delay in the feedback loops. Thus, control loops that rely on data from a fast, but noisy estimator technique limit the level of noise in the system that can be tolerated by the read channel.
Consequently, what is needed is a technique for reliably and accurately optimizing timing recovery, AGC control and adaptive equalization of a readback channel.

Magnetic recording channel utilizing control fields for timing recovery, equalization, amplitude and amplitude asymmetry

International Business Machines Corporation


A display pointing device (10) includes a fingerprint sensing circuit (18) that optically senses, for example, a portion of a fingerprint or other skin texture, and a fingerprint movement detection circuit (20), operatively coupled to the fingerprint sensing circuit (18), that is operative to determine a direction of movement and a rate of movement of skin texture being sensed by the fingerprint sensing circuit (18) to produce pointing output data (24) for a display (12). The pointing output data (24) may be, for example, data representing a visual indication of a position on a display screen, such as a position of a cursor or of highlighted text, or any other suitable position indication. A method for providing pointing information for display includes sensing a fingerprint, determining a direction of movement and a rate of movement of the fingerprint and producing a pointing output for display based on a determined direction of movement and rate of movement of the sensed fingerprint.

A pointing device, such as a mouse, allow a user to point to a position on a screen to interactively position a cursor or select a position on a display surface, such as a display screen or other suitable surface. Such pointing devices are known to be used in desktop computers, mobile devices, laptop computers, cell phones, PDAs, Internet appliances and other devices. The pointer on a display may be textual (e.g., highlighted text) or graphical (e.g., cursor).
User interfaces on portable consumer electronic products are getting more complex. This complexity generally requires more controls for the user to manipulate. However, consumer demands typically require products that are small and compact. It can be difficult to include sufficient controls and still keep the device small enough for consumer acceptance. There is also a practical limit on how small controls, such as buttons, may be placed with respect to each other and still remain operable by an average user's finger.
Two major classes of pointing devices exist on portable consumer electronic products, namely one dimensional and two dimensional pointing devices. A one dimensional pointing device may include, for example, thumbwheels, spinners, sliders, multi-position toggle switches, and rocker switches. These pointing devices are used to select movement in one dimension in a user interface, such as a graphical user interface, or other suitable interface. Movement in one dimension is generally interpreted as one of an up/down, forward/back and next/previous depending on the context of the product.
One dimensional pointing devices, such as wheels, can be constructed to use very little of the inherently limited surface area of a consumer product. For example, the edge of a wheel may be extended through a slot opening in a product housing and permit a user to roll the wheel in both directions by dragging a finger along the wheel edge tangent to its circumference. A disadvantage of such wheel controls is that the slot openings in the housing permit contaminants to enter the product.
Toggle switches and rockers are typically larger than wheels, and they require a surface area pad large enough to receive a user's fingertip. In some cases, rocker switches are implemented as two adjacent buttons linked by a common button bar. These devices can be engineered to preserve the environmental seal of the housing of the product. However, such devices have the disadvantages that they contain moving parts and can take up larger surface areas of the device compared to the other one-dimensional alternatives listed previously.
Two dimensional pointing devices include, for example, track pads, track balls, mice, joy sticks, and other devices. These types of pointing devices are typically used to select movement in two dimensions simultaneously within a user interface. Any two dimensional pointing device can also be used as a one dimensional pointing device if desired by trivially ignoring one of the dimensions sensed by the device. Two dimensional pointing devices are much more versatile than one dimensional pointing devices. Typically, two dimensional pointing devices are used to select and manipulate information in a two dimensional display by indicating a position (X, Y) on the display, where that position (X, Y) is associated with a function by way of a graphical user interface. Alternatively, a two dimensional pointing device can be used to control two independent aspects of a device, such as pitch versus timbre, and ailerons versus rudder, interest rate versus term.
Trackpads are flat surface areas that sense the absolute contact location of the user's fingertip on the flat surface area. A minimum size of a trackpad must therefore be somewhat larger than a user's fingertip to be effective; practically they exceed several times the size of the user's fingertip. An advantage of trackpads is that they usually require very little depth within a device housing with respect to the surface area that they require, and they can be environmentally sealed. However, due to the amount of surface area that trackpads require, they are not typically common on smaller products like handheld devices.
Track balls utilize a rolling sphere to provide a relative motion indication output for a user interface. The user touches the sphere and causes it to roll. The roll angle of the sphere is sensed to determine two-dimensional pointing information. The minimum diameter of a track ball is constrained by, for example, the size of the sensing apparatus used to determine rotation. A disadvantage of track balls is that they require depth within a housing on the same order of the track ball diameter. However, many portable consumer electronic products do not have the necessary depth to accommodate a track ball pointing device and related sensing mechanisms. In addition, track balls cannot be environmentally sealed and thus also permit contaminants to enter the product.
Joy sticks are typically not used in portable consumer electronic products, typically because they must project above the surface of the product and they can generally require significant volume or depth within the product for the sensing mechanisms. A variant of a joy stick, commonly referred to as a joybutton or hat switch, is usually implemented as a two-dimensional rocker switch. Among the disadvantages shared by a joybutton and a hat switch are that the device generally cannot indicate speed or distance, only direction.
The most common type of prior art mouse pointing device (plural: mice) operates substantially like an inverted track ball. Instead of the user touching and rolling the sphere directly, the user moves an entire housing containing the inverted track ball upon an auxiliary flat surface (a mouse pad) separate from the housing. The auxiliary flat surface has a minimum size determined by the size of the mouse housing, and in practice the minimum size of such a mouse pad is significantly larger than a user's palm. In use, the friction between the sphere and the mouse pad causes the sphere to rotate within the housing, at which point the remainder of the operation is similar to a track ball device. In addition to all of the disadvantages of a track ball, such existing prior art mice also appear to have the disadvantage of requiring the auxiliary flat surface, and the sensing of motion is necessarily conducted on the bottom of the housing.
Another prior art mouse implementation requires a fine regularly repeating optical pattern or grid printed on the mouse pad surface, on which the user slides an optical mouse. This type of optical mouse uses sensors necessarily on the bottom surface of the housing that are placed at a specific pitch relative to the grid on the mouse pad surface and thus senses the relative motion of the known grid underneath it and uses that information to sense direction and speed. However, disadvantages of the additional grid surface include the requirement for the mouse pad itself, and that the mouse pad is typically hard to keep clean and free from damage, the mouse pad is typically several times larger than the user's palm, and the user must take care to keep the orientation of the optical mouse consistent with the orientation of the grid on the mouse pad.
Another type of optical mouse such as an IntelliEye Optical Sensor™ marketed by Microsoft Corporation of Redmond, Wash. uses optical sensors and image processing techniques to determine relative motion. As with all other prior art mice implementations, this product requires an auxiliary surface on which to operate. This product is differentiated from the optical grid mouse previously cited in that it does not require a separate optical repeating grid pad and it uses a plurality of sensor arrays and an image processor to determine speed and direction of motion of a flat smooth surface below it. The sensor arrays are thus necessarily positioned on a bottom surface of the optical mouse. A flat sensing window on the bottom of the mouse receives light for the optical sensor arrays. In operation, a flat area, such as the top of a desk, is required to use the mouse. The minimum size of the flat area is at least as large as the mouse housing, which is about the size of a user's palm, and in practice the flat area required is several times larger than a user's palm. As such, an improved display pointing device would be desirable for portable consumer devices.

Compact optical pointing apparatus and method


In an ion generator comprising a discharge needle 2, an opposed electrode 3 opposite the discharge needle 2 and an AC high voltage power source 4, for generating positive and negative air ions by giving rise to a corona discharge when a high voltage is applied by the AC high voltage power source 4 between the discharge needle 2 and the opposed electrode 3, the AC high voltage power source 4 comprises a high frequency oscillator 7 and a piezoelectric transformer 9, and outputs a high frequency voltage. An insulator 5 is placed intervening between the high voltage output line 4a of the AC high voltage power source 4 and the discharge needle 2 to capacitance-couple them, and the discharge needle 2 is enabled to discharge electricity. Preferably, the surface of the opposed electrode 3 should be covered with an insulator. This enables the balance between positive and negative air ions and its stability to be improved while reducing the hardware configuration in size and weight.

There is already known an ion generator which applies a high voltage from an AC high voltage source of the commercial frequency (50 or 60 Hz) between a discharge needle and an opposed electrode, generates a corona discharge from the discharge needle and ionizes air by that corona discharge (see Japanese Patent Application Laid-Open No. 8-288094 for instance).
In an ion generator of this kind, positively charged air ions and negatively charged air ions are alternately generated by alternately applying an AC voltage to the discharge needle. And the ion generator of this kind, as it can neutralize the electric charges (static electricity) accumulated on the charged object with the generated positive and negative air ions, is generally used as a deelectrifying device for clearing charged objects of static electricity.
Further, a consideration is given in the ion generator of this kind to the short-circuiting current which may be generated when a human body or the like comes into contact with the discharge needle, and the short-circuiting current is restrained by capacitance-coupling the discharge needle with the high voltage output line from the AC high voltage source. In the ion generator in this case, at the time of generation of a corona discharge (at the time of discharge by the discharge needle) the impedance of the coupled capacitance of the discharge needle causes the discharge needle to reduce the voltage of the high voltage output line. In order to generate a corona discharge at the commercial frequency, the discharge needle requires a voltage of about 4 kV at its tip. For this reason, this ion generator uses an AC high voltage power source which outputs a high voltage, augmented with a compensation for the voltage drop due to the impedance of the coupled capacitance of the discharge needle, to the high voltage output line.
It is difficult here for the discharge needle to have a very large coupled capacitance because of structural constraints and the need to secure the effect to restrain the short-circuiting current, and the capacitance can be at most 10 pF or so for practical purposes. As a result, the voltage drop attributable to this coupled capacitance increases. In a case in which coupled capacitance is 10 pF and the commercial frequency is 50 Hz, the voltage drop will reach about 1.6 kV. Incidentally, the discharge current of the discharge needle is about 3 μA to 10 μA, and the above-mentioned level of the voltage drop is what matches a discharge current of 5 μA. Therefore, in order to compensate for this voltage drop, the conventional ion generator uses as the boosting transformer for the AC high voltage power source a wound-wire transformer having a sufficient number of windings to generate a high voltage of about 6 to 9 kV. However, since a wound-wire transformer is relatively large and heavy, this involves a problem of difficulty to make the ion generator compact and light.
On the other hand, there is also known an ion generator using a piezoelectric transformer, which is more compact and lighter than a wound-wire transformer and an AC high voltage power source of a high frequency of a few tens of kHz instead of the commercial frequency (see Japanese Patent Application Laid-Open No. 2003-22897 for instance). The AC high voltage power source of this ion generator generates a high frequency AC high voltage by providing a high frequency signal of a few tens of kHz from a high frequency oscillator to the piezoelectric element of the piezoelectric transformer. An ion generator using such a high frequency power source, compared with what uses a power source of the commercial frequency, can improve the ion balance of air ions (the balance between the quantity of positive ions and that of negative ions), and moreover can reduce the voltage needed for generating a corona discharge from the tip of the discharge needle to about 1.8 kV.
The output voltage of the high frequency power source using this piezoelectric transformer is at most about 2 to 3 kV because of the characteristics of the piezoelectric transformer, and this output voltage is close to the voltage (about 1.8 V) needed by the discharge needle to generate a corona discharge by using that high frequency power source. Therefore, in order to secure the voltage of the discharge needle at a level allowing the generation of a corona discharge, the voltage drop from the high frequency power source to the discharge needle has to be kept sufficiently small. As the current a piezoelectric transformer can output is generally small (at most about 100 μA), the short-circuiting current can be kept sufficiently small without having to capacitance-couple the discharge needle with the high voltage output line.
On account of these circumstances, in the conventional ion generator using a high frequency power source, the high voltage output line is directly connected to the discharge needle (the discharge needle is not capacitance-coupled with the high voltage output line) so that no superfluous voltage drop may occur between the high voltage output line of the high frequency power source and the discharge needle.
Incidentally, the requirement for neutralizing charged objects wherever practicable on the production lines of precision semiconductor devices and elsewhere has become even more stringent in recent years. In meeting this requirement, an ion generator using a high frequency power source is more advantageous than an ion generator using a commercial frequency power source. However, in the conventional ion generator using a high frequency power source, the ion balance is often destabilized, and the requirement cannot be always fully satisfied.
An object of the present invention, attempted in view of these background circumstances, is to provide an ion generator reduced in the size and weight of hardware configuration and capable of improving the balance between positive and negative air ions and its stability.


A distributed control system for a vehicle includes a configuration controller and at least three nodes communicatively coupled to the configuration controller. Each of the at least three nodes includes a memory device for storing local data and portions of shared data of the distributed control system. Further, portions of the shared data are dissimilarly copied across the at least three nodes using dissimilar methods. More specifically, the dissimilar methods include at least one of striping the shared data amongst the at least three nodes, storing parity information of the shared data amongst at least one of the at least three nodes, storing unique identification or signatory information of the shared data amongst at least one of the at least three nodes, storing subsets of the shared data amongst the at least three nodes, and/or storing exact copies of the shared data amongst at least one of the at least three nodes so as to increase redundancy of the shared data.

An engine controller configured to control operation of a gas turbine engine traditionally receives configuration data for the gas turbine engine via a plug-based system that stores a single hardware copy of the configuration data. The plug-based system may include one or more plugs configured to store the configuration data. For example, the plug-based system may include an engine rating plug, a configuration plug, or both. More specifically, the engine rating plug may provide data indicative of a thrust rating for the gas turbine engine. Alternatively or additionally, the configuration plug may provide data indicative of one or more configuration settings for a core module or hardware variant of the gas turbine engine. The one or more plugs may be communicatively coupled to the engine controller. In this manner, the engine controller may be configured to control operation of the gas turbine engine differently based on the data received from the plug(s).
However, the plug(s) add to the overall weight and cost of the gas turbine engine, which is generally undesirable. Recent systems have looked into distributed memory to serve this purpose, but such systems require many large memory devices and thus large bandwidth requirements to communicate this information.
Accordingly, the present disclosure is directed to an improved engine management controller that allows for variously sized and even very small memory devices to be used in each location but which still retain the full amount of available engine information with the removal and replacement of any of the LRUs. Thus, the engine controller of the present disclosure simplifies the system and has reduced overall weight and complexity as compared to conventional controllers.

Data configuration management system for an engine


An apparatus for accurately measuring pressure within a rechargeable cell, the apparatus comprising: a frame, the frame including at least one cavity adapted to releasably seat a rechargeable cell; a fixed brace defining a first end of the at least one cavity; a movable brace defining the end of the at least one cavity opposite from the fixed brace, the movable brace including a hollow needle, the hollow needle having a pointed end which is operatively directed toward one end of a rechargeable cell disposed in the cavity, and means for sealing a point where the hollow needle is inserted into a rechargeable cell; a pressure transducer operatively connected with the hollow needle; and means for controllably moving the movable brace relative to the fixed brace, whereby the hollow needle is adapted for insertion into and removal from a rechargeable cell disposed in the cavity.

Rechargeable electrochemical cells may be used as direct replacements for primary AA, C, and D cells in numerous consumer devices such as calculators, portable radios, and flashlights. Often, rechargeable cells are integrated into a sealed power pack that is designed to interface with a specific device. In sealed power packs, weight and portability are important considerations. Long operating life and maintenance free operation are desirable characteristics for all rechargeable cells.
A rechargeable cell is ideally suited to serve as a portable power source due to its small size, light weight, high power capacity and long operating life. A rechargeable cell may operate as an "install and forget" power source. With the exception of periodic charging, such a rechargeable cell typically performs without attention and rarely becomes the limiting factor in the life of the device it powers.
Rechargeable cells using a hydrogen storage negative electrode are known in the art. See, for example, U.S. Pat. No. 4,551,400 (hereinafter "the 400 patent") for HYDROGEN STORAGE MATERIALS AND METHODS OF SIZING AND PREPARING THE SAME FOR ELECTROCHEMICAL APPLICATIONS, the disclosure of which is incorporated by reference. (Cells using rechargeable hydrogen storage negative electrodes are hereinafter referred to as "hydrogen storage cells.") Hydrogen storage cells operate in a different manner from lead-acid, nickel-cadmium, or other prior art battery systems. The metal hydride negative electrode used in hydrogen storage cells is capable of the reversible electrochemical storage of hydrogen. In hydrogen storage cells, the positive electrode is typically formed of a nickel hydroxide material. A suitable separator, spacer, or membrane may be positioned between the negative and positive electrodes.
Hydrogen storage cells operate with a nickel hydroxide positive electrode; a hydrogen storage alloy negative electrode; and a non-woven, felted, nylon or polypropylene separator. The electrolyte is generally 20 to 45 weight percent potassium hydroxide.
Hydrogen storage cells offer important advantages over conventional rechargeable cells. Hydrogen storage cells have significantly higher specific charge capacities (both in terms of ampere hours per unit mass and ampere hours per unit volume) than do cells that use lead or cadmium negative electrodes. As a result of the higher specific charge capacities, a higher energy density (in terms of watt hours per unit mass or watt hour per unit volume) is possible with a hydrogen storage cell than is possible with prior art systems such as the lead acid and NiCd. Thus, hydrogen storage cells are particularly suitable for many commercial applications.
The operation of a hydrogen storage cell produces hydroxyl ions, and may also produce gases under certain circumstances. As a result, the internal cell pressures may vary substantially during operation of a hydrogen storage cell. Because of this, hydrogen storage cells are typically produced as either sealed cells or vented cells. During normal operation, a sealed cell does not permit the venting of gas to the atmosphere. In contrast, a vented cell will release excess pressure by venting gas as part of its normal operation. As a result of this difference, the vent assemblies used in sealed and vented cells are quite different from one another, and the amounts of electrolyte in the cell container relative to the electrode geometry differ significantly.
Sealed cells are manufactured predominantly in cylindrical and rectangular configurations. Sealed cells are usually designed to operate in a starved electrolyte configuration. The cell enclosure for a sealed cell is normally metallic and designed for operation at pressures up to about 100 pounds per square inch absolute or even higher. Sealed cells are characterized by the substantial absence of any required maintenance.
A variation of sealed cells are cells containing "one time only" venting mechanisms, for example, a rupturable diaphragm and blade apparatus. As internal pressure increases, the blade is forced against the diaphragm. As the pressure further increases to the pressure limits of the particular cell configuration, the blade punctures the diaphragm, allowing excess gases to escape through the ruptured diaphragm without catastrophic cell failure.
Vented hydrogen storage cells, which have a nickel hydroxide positive electrode, and a hydrogen storage alloy negative electrode, typically employ a woven or non-woven separator. Vented cells differ most significantly from sealed cells in that they operate in a flooded condition. A "flooded condition", as used herein, refers to a cell in which the electrodes are completely immersed in electrolyte. Such cells are sometimes referred to as "flooded cells." A vented cell is further distinguished from a sealed cell in that it is designed for normal operating pressures of only up to about 10 pounds per square inch, after which excess pressures are relieved by a vent mechanism.
As discussed above, operation of a hydrogen storage cell produces hydroxide ions and can produce various gases. The amount of gases generated depends on the amount of electrolyte, the operating temperature, as well as variations in components, chemical concentrations, and manufacturing techniques.
Quality control review of all types of rechargeable cells generally involves measuring the pressures developed in finished cells during charge/discharge cycling. There are several methods of pressure measurement known in prior art. One involves the use of a strain gauge. Once amount of strain induced by the pressures developed in a cyclindrical can are very small. Unless very sensitive strain gauges are used, the measurements will be erroneous. A "one time only" method of instantaneous pressure measurement involves puncturing the can with a sharp "nail like" device connected to a gauge. Once measured, the cells cannot be resealed. With this method it is impossible to make multiple pressure measurements. The third method involves putting a hole through the lid or side and connecting a transducer to it. The disadvantage of this is that even a small amount of pressure in the cell serves to expel electrolyte through the drilled hole, thereby reducing the quantity of the electrolyte. Since the quantity of electrolyte lost is unpredictable and since pressure is dependent upon the quantity of electrolyte, pressures measured in this manner cannot be meaningfully interpreted. Additionally, meaningful data requires the measurement of pressure over hundreds of charge/recharge cycles. The pressure measurement techniques of the prior art required a new cell to be sacrificed for each measured data point.
Thus, not only were hundreds of cells sacrificed for each set of measurements, but variations from cell to cell had to be taken into consideration in interpreting the results.
The hydrogen storage cells described in the '400 patent, require a heat treatment process for activation. Pressure tends to build up within the cell during this activation process. When a hole is made in the can in order to make a pressure measurement, this activation process greatly contributes to the loss of electrolyte. Even if the hole is formed prior to charge/discharge cycling, the activation process nonetheless initiates a pressure rise and a corresponding loss of electrolyte, which results in a reduction of the internal pressure. Tape cannot be used to cover the hole as the electrolyte tends to "creep" through the hole and destroy the adhesive on the tape. Even in those instances in which the tape survives the initial activation, the pressure rise causes electrolyte leakage when the tape is punctured after heat treatment. Attempts to secure the tape to cover the hole internally have been unsuccessful because the tape interferes with the process of inserting the core into the can; and the electrolyte attacks and eventually releases the adhesive.
A need exists to more efficiently measure the internal pressure in all types of rechargeable cells, particularly metal hydride cells, during normal and worst case operation. Such a pressure measurement must be non-destructive and compatible with continuous charge/discharge cycling of the cell so that the pressures resulting from actual use of the cell can be determined without loss of electrolyte.

Apparatus for measuring the pressure inside a rechargeable electrochemical cell


Disclosed herein is a dual blood glucose meter. The dual blood glucose meter includes a meter body, a measurement strip, a variety of electronic parts and upper and lower strip receiving ports. The meter body is provided with a liquid crystal display panel on the front thereof to display measured numerical values and various pieces of pictorial information. The measurement strip is brought into contact with blood at a blood collection spot so as to measure blood glucose of the blood. The electronic parts are used to measure the blood glucose of the blood. The upper and lower strip receiving ports are formed at upper and lower ends of the meter body to receive the measurement strip, and are each electrically connected to the electric parts.

1. Field of the Invention
The present invention relates generally to blood glucose meters and, more particularly, to a dual blood glucose meter, which allows a measurement strip to be inserted into one of upper and lower ends thereof, thus considerably improving the user's convenience at the time of measuring blood glucose.
2. Description of the Related Art
Recently, as the function and performance of electronic products are rapidly developing, many efforts have been made to improve the convenience of the use for electronic consumer products, such as home appliance.
Such a tendency is the same in the field of medical devices. For medical devices that consumers directly select and use, the convenience of use thereof has been stressed as much as the performance thereof has.
Of such medical devices, there is a blood glucose meter. As known well, the blood glucose meter is a device that allows diabetics, who require an adjustment of blood glucose, to easily measure the concentration of blood glucose in their blood.
In an early stage, blood glucose is measured using an early blood glucose meter installed at a hospital after a serum and corpuscles are separated from blood. Thereafter, there was developed a next generation technology that eliminated the needs of wiping away blood or removing blood corpuscles. The next generation technology is classified into a light intensity measurement method or an electrochemical measurement method. In the next generation technology, a measurement member, collectively called a strip, is used. In this case, the strip refers to only a measurement member used in the light intensity measurement method in the strict sense. The measurement member used in the electrochemical measurement method is referred to as a biosensor.
A light intensity measurement method is a method using the oxidation reaction of glucose by an oxidizing enzyme and a peroxidase as a basic principle. The light intensity measurement method is constructed so that the concentration of blood glucose is measured by analyzing a variation in the color of a reacted indicator. In the light intensity method, blood glucose is measured in such a way as to smear blood on the surface of reaction paper, to remove the blood after an elapse of predetermined reaction time, to place an opaque reflection plate under the reaction paper to reflect light, to radiate a certain amount of light from a light emitting means to the surface of the reaction paper and to utilize the amount of reflected light.
However, the light intensity measurement method is problematic in that accurate measurement is not achieved because reaction is not uniform in the case where the blood is removed when an actual reaction period exceeds or is short of an appropriate reaction period after the blood is smeared on the reaction paper. The light intensity measurement method is problematic in that the accurate measure of blood glucose because a difference in measured values occurs depending on the material of the reaction paper or force applied to the reaction paper when the blood is removed from the upper surface of the reaction paper to allow the light to be directly radiated to the reaction paper. Furthermore, the light intensity measurement method is problematic in that the use and change of the reaction paper is inconvenient and the number of the steps of measurement and measurement time are increased, thus decreasing the efficiency of measurement.
A method of measuring blood glucose proposed to overcome the above disadvantage is an electrochemical measurement method. This electrochemical measurement method is a method of measuring electrons involved in the process in which the oxidizing enzyme of glucose reacts with an electrode, using an electrical medium instead of a pigment source. When a blood sample is coated on the reacting layer of a measurement sensor used as a measurement sensor, blood glucose in the blood is oxidized by the oxidizing enzyme and the oxidizing enzyme is deoxidized. At this time, an electron acceptor oxidizes the oxidizing enzyme and deoxidizes itself. Accordingly, the deoxidized electron acceptor loses electrons and is electro-chemically oxidized again at an electron surface to which a certain voltage is applied. Since the amount of current generated at that time is proportional to the concentration of glucose in the blood, the concentration of the glucose in the blood is measured by measuring the amount of current.
As described above, a blood glucose meter for electrochemically measuring the concentration of blood glucose measures the blood glucose using the measurement of the amount of current, the concentration of blood glucose can be relatively correctly measured, measurement time can be reduced, and the performance of use, including the convenience of use, can be considerably improved.
The electrochemical blood glucose meter is designated by reference numeral 101 in FIG. 1, and includes a meter body 103 and a measurement strip 105 inserted into an upper end of the meter body 103. As illustrated in FIG. 1, the measurement strip 105 is provided at the upper end of the meter body 103 in view of the fact that blood is collected at the tip of a finger. Furthermore, a strip receiving hole 112 is formed at the upper end of the meter body 103. A Liquid Crystal Display (LCD) panel 107 is mounted on the upper portion of the front of the meter body 103 to display a measured value and various pieces of pictorial information in the form of numbers and icons. A power switch 109 and a control switch 111 are placed in the vicinity of the panel 107.
When blood glucose is measured using the blood glucose meter 101, a drop of blood is collected in such a way as to turn on the power switch 109, clean a point of a finger from which blood is collected, remove moisture, and cut the tip of the finger using a bloodletting device. Thereafter, when the measurement strip 105 is brought into contact with the drop of blood, the value of blood glucose is displayed on the display panel 107.
To measure blood glucose as described above, the tip of a finger is cut using such a bloodletting device or the like as illustrated in FIG. 2, which allows a sufficient amount of blood to be collected, but is disadvantageous in that a pain occurs at the cut point of the finger.
When blood is collected on at an inside point of a forearm to overcome the above-described problem, as illustrated in FIG. 3a, a pain is scarcely felt, but an inconvenience arises in that the meter body 103 is turned upside down and, thus, it becomes difficult to identify numbers or icons displayed on the display panel 107. In contrast, it is possible to bring the measurement strip 105 to a blood collection point 110 while holding the meter body 103 erect so as to allow the display panel 107 to be easily viewed, as shown in FIG. 3b. However, in this case, the right wrist gripping the blood glucose meter is excessively bent, which causes the inconvenience of use in view of ergonomics.


Disclosed are a white light emitting diode and a method for manufacturing the white light emitting diode. The white light emitting diode comprises a conductive substrate with a light transmitting property having a surface divided into first and second areas; a first emitting unit including a first clad layer, a first active area, and a second clad layer at the first area of the conductive substrate; a second emitting unit including a third clad layer, a second active area emitting light with a wavelength to be combined with light emitted from the first active area into white light, and a fourth clad layer at the second area of the conductive substrate; and first, second and third electrodes, the first electrode connected to the second surface of the conductive substrate, the second electrode connected to the second clad layer, and the third electrode connected to the fourth clad layer.

1. Field of the Invention
The present invention relates to a white light emitting diode, and more particularly to a white light emitting diode, into which active layers for respectively emitting red, green and blue light are integrated, and a method for manufacturing the white light emitting diode.
2. Description of the Related Art
As well known to those skilled in the art, white light emitting diodes are widely used as backlights of lighting apparatuses or display units. Methods for manufacturing a white light emitting diode are mainly divided into two types, i.e., a method using a luminescent material and a method simply combining blue, red and green LEDs, which are respectively produced.
First, the method for manufacturing a white light emitting diode using a luminescent material is divided into a method using a blue light emitting diode and a method using an ultraviolet light emitting diode. For example, in the method using a blue light emitting diode, blue light is inverted in terms of wavelength into white light using a YAG (Yttrium-Aluminum-Garnet) luminescent material. That is, the blue light emitted from a blue LED excites the YAG luminescent material, thus allowing a manufactured device to emit white light.
FIG. 1a is a schematic cross-sectional view of a conventional white light emitting diode 20 using a YAG luminescent material. With reference to FIG. 1a, the white light emitting diode 20 comprises an InGaN blue LED 10 mounted on a cap of an anode lead frame 12, and a YAG luminescent material 15 surrounding the InGaN blue LED 10 within the cap. The InGaN blue LED 10 is connected to the anode lead frame 12 and a cathode lead frame 14 by wires 11 and 13, respectively. The upper surfaces of the lead frames 12 and 14, on which the InGaN blue LED 10 is mounted, are molded with a transparent material 17.
Power is supplied to the InGaN blue LED 10 through the lead frames 12 and 14, so that the InGaN blue LED 10 emits blue light. A part of the emitted blue light excites the YAG luminescent material 15. Here, the YAG luminescent material 15 is characterized in that it is excited at a peak wavelength (460 nm) of the InGaN blue LED 10, thus emitting fluorescent yellowish green light. The fluorescent yellowish green light obtained from the YAG luminescent material 15 is combined with the remaining part of the blue light emitted directly from the InGaN blue LED 10, thereby being finally emitted as white light.
The conventional white light emitting diode 20 shown in FIG. 1a is advantageous in that it does not require current regulation to be adapted in use of LEDs respectively emitting RGB (Red/Green/Blue) light. Similarly to the above method for manufacturing the conventional white light emitting diode 20, there are a method using an ultraviolet light LED and a method using RGB light luminescent materials in combination.
However, in case that the wavelength modulation is employed as described above, there are drawbacks such as the reduction of optical efficiency in exciting the luminescent material and the reduction of a color correction factor.
There is another conventional white light emitting diode using RGB LEDs. FIG. 1b is a schematic cross-sectional view of a conventional white light emitting diode 30 using RGB LEDs. With reference to FIG. 1b, the white light emitting diode 30 comprises three LEDs 23, 25 and 27, which are produced as components. The LEDs 23, 25 and 27 are mounted on a single printed circuit board 21 via wires 22. The white emitting diode 30 shown in FIG. 1b emits white light by combining different lights (for example, R, G and B light) emitted from the respective LEDs 23, 25 and 27.
Such a white light emitting diode eliminates problems raised by the use of the luminescent material, thus obtaining excellent color sensitivity. However, the above white light emitting diode requires plural LEDs, thereby increasing the production cost. Further, the above white light emitting diode must regulate the current supplied to respective LEDs so as to obtain the desired white light, thus requiring a complicated circuit configuration.

White light emitting diode and method for manufacturing the same