Nec Communication Systems, Ltd.

Nec Corporation

Nihon Parkerizing Co., Ltd.

Advanced Telecommunications Research Institute International

Nec Tokin Corporation

Tokyo Tanabe Company, Ltd.

Nec Communications Systems, Ltd.

Mitsubishi-Tokyo Pharmaceuticals, Inc.

Hiroyuki Iizuka

Tetsuya Ito

Yuichiro Ezure

Akira Matsumoto

Kenichi Abe

Sadao Obana

Masahito Iwai

Koichi Yoshimura

Toshiyasu Tanaka

Toru Yamamoto

Nobuyuki Yasuda

Hiroshi Yageta

Jun Kawaguchi

Satoko Itaya

Yoshihisa Kondo

Masato Shirakata

Peter Davis

Hiroyuki Yomo

Akio Hasegawa

Naoto Kadowaki

Suhua Tang

Hidemasa Kawai

Toshifumi Matsumoto

Kiyokazu Murakami

Jun Hasegawa

Susumu Yokura

Norihide Ohyama

Kouichi Matsunaga

Eiji Ohtubo

Nobuo Takoi

Yoshiaki Takakura

Hidehiro Endou

Tetsuya Takashima

Ikuo Kojima

Susumu Tsuchiya

Kozo Hiratsuka

Atsusi Hukuzaki

A sensor network systemis provided with a plurality of sensor nodes, . . . and configured to decide a parent node for each of the plurality of sensor nodes so as to form a network topology having a tree structure using each of the plurality of sensor nodes as a node. The sensor network system forms the network topology so that, with respect to each of the plurality of sensor nodes, the number of child nodes owned by the sensor node is close to a value obtained by multiplying a maximum containing number, which is a maximum number of sensor data that can be contained by one packet, by a natural number ().

Sensor network system, sensor network control method, sensor node, sensor node control method, and sensor node control program

A packet interval (a time difference between sequentially received packets) in a certain previous time is calculated and a cumulative distribution function of the calculated packet interval is obtained. Meanwhile, a function value-corresponding to-flow end that is a boundary value of the cumulative distribution function to be considered as a flow end (timeout) in the range of a cumulative distribution function value is stored. From the cumulative distribution function obtained as described above, a value of a packet interval mapped to a cumulative distribution function value that matches the function value-corresponding to-flow end is set as a threshold. That is, the threshold is dynamically set based on a previous packet interval. Therefore, a packet stop period from a last packet reception time to a current time is measured, and it is detected as a flow timeout at a timing when the measured value is equal to or greater than the threshold.

Communication apparatus, communication state detecting method, and communication state detecting program

A terminal devicetransmits a wireless frame having a frame length or amplitude that represents the ID of a wireless base stationto be woken up to the wireless base station. The wireless base stationdetects the wakeup ID from the frame length or amplitude of the wireless frame from the terminal device, and, if the detected wakeup ID is identical with its own ID, transitions from a sleep mode to an operating mode. In this case, the wireless frame is the same wireless frame as that transmitted and received by the wireless communication module of the terminal deviceto and from the wireless base station

Terminal device, wireless base station wirelessly communicating with the same, and wireless communication system using terminal device and wireless base station

The present invention is to allow prompt and reliable synchronization of belonging information management table even in environments where there is a possibility of receiving update notification information from a plurality of wireless base stations, without needing unnecessarily large traffic for synchronization of belonging information management table. Wireless base station stores belonging information management table, to which belonging information of a terminal belonging to the base station is associated with, to new/old judgment information for judgment of new/old of update. Belonging information update unit performs update of belonging information including the new/old judgment information thereof. Further, upon receiving update notification information from other wireless base station, the belonging information update unit updates the belonging information management table based on the update notification information. The update notification information includes at least updated portion in the belonging information and new/old judgment information.

Wireless base station, communication system, belonging information management method and storage medium for storing program

A wireless communication system allocates resource information used in performing wireless communication to wireless base stations in order not to generate interference between access-side wireless interfaces and backbone-side wireless interfaces. Each of the wireless base stations includes an access-side wireless interface for covering wireless terminal devices and a backbone-side wireless interface for connecting the wireless base stations with each other. The wireless base station allocates resource information that is common to the wireless base stations to the backbone-side wireless interface that performs the wireless communication between the wireless base stations, and allocates resource information that does not generate interference with the backbone-side wireless interface to the access-side wireless interface.

Resource allocation apparatus, central control apparatus, wireless base station, wireless communication system, resource allocation method and resource allocation program in computer-readable medium

The use of a wireless interface is dynamically changeable according to connection states of stations belonging to access points. Therefore, limited wireless interfaces are efficiently utilized without requiring operation in which the user conducts a complex setting operation. First, connection states of stations belonging to access points are measured. Based on information of the connection states, the connection destination of a wireless connection unit of an access point under consideration is changed over between an access point and a station.

Wireless communication system, system controller, access point, station, communication control method and computer-readable medium storing communication control program

The route maintenance unit outputs a period setting request to the period setting unit when the communication unit normally receives a Hello packet for the first time. The period setting unit sets a link connection confirmation period in response to the period setting request and outputs the set period to the route maintenance unit. The route maintenance unit maintains a radio link between the radio device in which the route maintenance unit is provided and an adjacent device upon receiving a data packet other than a Hello packet from the adjacent radio device even if a Hello packet is not received in the link connection confirmation period. Consequently, route disconnection or switching occurs less often.

Radio device having fewer route disconnections and switchings by using control packets to maintain radio links

A film-sealed nonaqueous electrolyte battery comprises: a battery element including a non-aqueous electrolyte; a film case having at least a sealant polymer resin film for sealing the battery element; at least a lead terminal extending from the battery element and projecting from the film case, and the lead terminal with a surface having a contact area in contact directly with the sealant polymer resin film, and at least the contact area of the surface of the lead terminal is coated with an anti-corrosion coating film, wherein the anti-corrosion coating film includes: (A) a polymer of structural units of a phenolic compound, and at least a part of the structural units includes a substituent which comprises an amino group or a substituted amino group; (B) a phosphate compound; and (C) a titanium fluorine compound.

Film-sealed non-aqueous electrolyte battery with improved surface-treated lead terminal

There is provided a surface treatment method of metal that can endow the surface of a metallic material with strong bonding force in a simple process regardless of the profile and the substance of the metallic material as well as a metallic material obtained by such a method. The method comprises a first step of conducting a chemical etching process accompanied by formation of a film coat on the metal surface and a second step of chemically removing the film coat formed on the metal surface in the first step. If necessary, it may further comprise a third step of forming a thin layer on the metal surface after the second step.

Surface treatment process of metallic material and metallic material obtained thereby

Phenylethanolamine compounds useful as .beta. 3 agonists, process for

A Saishin N derivative represented by the following general formula: ##STR1## wherein X represents a carbonyl group or a &gt;CH--ORx group, or X bonds to a carbon atom in Y or Z to represent a &gt;C(ORx)--O-- group; Y and Z may be the same or different and each represents a carbonyl group or a &gt;CH--ORy group, or each bonds to an oxygen atom in X to represent a &gt;CH-- group; the broken line represents an optional bond; and Rx and Ry may be the same or different and each represents a hydrogen atom or an alkyl, alkenyl, aralkenyl, aralkyl, heterocyclic-alkyl or acyl group, is provided which is therapeutically usable as an antiulcer agent.

Saishin N compounds, process for preparing same and antiulcer agents

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Tokyo, Japan

Hiroyuki Iizuka