Patents Assigned to Nippon Telegraph and Telephone Corporation
  • Patent number: 7652998
    Abstract: A multicast communication path calculation method is disclosed which includes the steps of: obtaining minimum delay paths from a source node to each destination node; selecting, as candidate nodes of a rendezvous point node, nodes on one of the obtained minimum delay paths; for each candidate node, calculating minimum delay paths from the candidate node to each destination node, and obtaining a difference between the maximum value and the minimum value among delays of the calculated minimum delay paths; selecting, as the rendezvous point node, a candidate node by which the difference is smallest; and outputting a minimum delay path from the source node to the rendezvous point node and minimum delay paths from the rendezvous point node to each destination node.
    Type: Grant
    Filed: December 10, 2003
    Date of Patent: January 26, 2010
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Seisho Yasukawa, Koji Sugisono, Masanori Uga
  • Publication number: 20100014583
    Abstract: A quantization control method used in a video encoding which encodes a video image and performs control for making an encoding bit rate approach a predetermined target bit rate. The quantization control method includes measuring a differential amount of code between a target amount of code and an amount of generated code; determining whether or not a predetermined condition has occurred; determining, when it is determined that the condition has occurred, a variation for an amount of feedback which increases or decreases a quantization step size, and changing the amount of feedback based on the determined variation; and increasing or decreasing the quantization step size based on the measured differential amount of code and the changed amount of feedback. If there are a plurality of the predetermined conditions, a final variation for the amount of feedback may be determined by applying a specific operation to variations for the amount of feedback, which are determined for the individual conditions.
    Type: Application
    Filed: March 5, 2008
    Publication date: January 21, 2010
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Atsushi Shimizu, Ryuichi Tanida
  • Publication number: 20100017373
    Abstract: In encoding for putting one or more files and/or one or more files in a folder into a single archive file, original hierarchy information and standard hierarchy information generated by converting characters in a special character coding in each file name to characters in a standard character coding are recorded in the archive file. If the character coding used in the original hierarchy information in the archive file cannot be used in the system environment used in decoding, a file name in the standard character coding is generated from the standard hierarchy information and is converted to a character coding that can be used in the system environment.
    Type: Application
    Filed: December 28, 2007
    Publication date: January 21, 2010
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Noboru Harada, Takehiro Moriya, Yutaka Kamamoto
  • Publication number: 20100008422
    Abstract: A video encoding method includes selecting a reference vector target frame and a reference frame from among already-encoded frames; encoding information for designating each frame; setting a reference vector for indicating an area in the reference vector target frame with respect to an encoding target area; encoding the reference vector; performing a corresponding area search by using image information of a reference vector target area, which belongs to the reference vector target frame and is indicated by the reference vector, and the reference frame; determining a reference area in the reference frame based on the search result; generating a predicted image by using image information of the reference frame, which corresponds to the reference area; and encoding differential information between image information of the encoding target area and the predicted image.
    Type: Application
    Filed: October 24, 2007
    Publication date: January 14, 2010
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Shinya Shimizu, Hideaki Kimata, Kazuto Kamikura, Yoshiyuki Yashima
  • Patent number: 7647209
    Abstract: A frequency domain transforming section transforms mixed signals observed by multiple sensors into mixed signals in the frequency domain, a complex vector generating section generates a complex vector by using the frequency-domain mixed signals, a normalizing section generates a normalized vector excluding frequency dependence of the complex vector, and a clustering section clusters the normalized vectors to generate clusters. Then, a separated signal generating section generates separated signals in the frequency domain by using information about the clusters and a time domain transforming section transforms the separated signals in the frequency domain into separated signals in the time domain.
    Type: Grant
    Filed: February 7, 2006
    Date of Patent: January 12, 2010
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Hiroshi Sawada, Shoko Araki, Ryo Mukai, Shoji Makino
  • Patent number: 7641397
    Abstract: The head end surface of an optical fiber (2) and the head end surface of an optical fiber (12) are butted to each other in an alignment member (22) of an adapter (21). In the butting, because one of the members clasping the optical fiber (2) is a plate (4a) that is short, the optical fiber (2) is bent and buckled between the left end of the short plate and the right end of the alignment member. Members clasping the optical fiber (12) are a long plate (14b) and a V-grooved base plate (13), and the optical fiber (12) is therefore horizontally fixed between each of right ends of the long plate and of the V-grooved base plate (13) and the left end of the alignment member. This results that the head end surface of the optical fiber (2) and the head end surface of the optical fiber (12) are in tight contact with each other, achieving excellent optical transmission between both optical fibers.
    Type: Grant
    Filed: August 31, 2004
    Date of Patent: January 5, 2010
    Assignees: Japan Aviation Electronics Industry, Limited, Nippon Telegraph and Telephone Corporation, Hirose Electric Co., Ltd.
    Inventors: Yuichi Koreeda, Akihiro Onogawa, Yoshiteru Abe, Masaru Kobayashi, Ryou Nagase, Masahiro Tsuchida, Koichi Arishima
  • Patent number: 7640431
    Abstract: A method for embedding digital watermark data in digital data contents includes the steps of obtaining a frequency coefficient of block data of digital data contents, obtaining a complexity of the block data, obtaining an amount of transformation of the frequency coefficient from the complexity and the digital watermark data, and embedding the digital watermark data by transforming the frequency coefficient. In addition, a method for reading digital watermark data includes the steps of calculating a probability of reading ‘1’ or ‘0’ in a read bit sequence by using a test method on the basis of binary distribution, determining the presence or absence of digital watermark data according to the probability, and reconstituting digital watermark data. Another method includes the steps of performing soft decision in code theory by assigning weights to the digital watermark sequence with a weighting function, and reconstituting digital watermark data.
    Type: Grant
    Filed: August 4, 2003
    Date of Patent: December 29, 2009
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Hiroshi Ogawa, Takao Nakamura, Atsuki Tomioka, Youichi Takashima
  • Patent number: 7637673
    Abstract: A straight type optical connector enables a splicing operation of an optical fiber cable accurately and stably without requiring skilled labor and having a superior on-site installation property. An optical connector is provided with a splicing section for securely supporting an incorporated optical fiber securely supported at a ferrule and an optical fiber of an outside optical fiber cable in an end-abutting condition. The body of the optical connector is provided with a cable holding member able to hold an optical fiber cable. The cable holding member can be set at a temporary position where it makes an optical fiber of the optical fiber cable abut against the incorporated optical fiber at the splicing section in the state holding the optical fiber cable and bends a covered optical fiber of the optical fiber cable between the splicing section and the cable holding member by a pressing force in the lengthwise direction.
    Type: Grant
    Filed: June 23, 2005
    Date of Patent: December 29, 2009
    Assignees: 3M Innovative Properties Company, Nippon Telegraph and Telephone Corporation
    Inventors: Tomayasu Oike, Takaya Yamauchi, Akihiko Yazaki, Tsunetaka Ema, Kenichi Nakazawa, Yasuhiko Hoshino
  • Patent number: 7636547
    Abstract: A reactance adjuster includes an electrode (123) inducing an electric-field in an electric-field transmittable medium (121), an adjusting signal generation section (13) outputting alternatingly a high level or a low level signal to a resonance section (7), an electric-field detection section (15) generating an electric signal based on the electric-field in the medium (121), a first electric-charge storing means (C1) storing electric-charge according to the electric signal when the section (13) outputs a high level signal, a second electric-charge storing means (C2) storing electric-charge according to the electric signal when the section (13) outputs a low level signal, a voltage comparator (10) outputting a predetermined signal based on a voltage difference between the storing means, a control section (19) outputting a constant voltage when the first and the second storing means (C1, C2) are storing electric-charge and a voltage based on a predetermined signal when the storing ends.
    Type: Grant
    Filed: December 1, 2004
    Date of Patent: December 22, 2009
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Tadashi Minotani, Nobutarou Shibata, Mitsuru Shinagawa
  • Patent number: 7636942
    Abstract: A monitoring device monitors a packet transmitted to a communication device that is a target of the denial-of-service attack, and detects traffic abnormality information indicating an abnormality of traffic due to the packet with respect to the communication device. A performance measuring device measures performance of the communication device, and detects performance abnormality information indicating an abnormality of throughput of the communication device. An attack determining device determines whether the communication device received the denial-of-service attack, based on the traffic abnormality information and the performance abnormality information.
    Type: Grant
    Filed: August 19, 2005
    Date of Patent: December 22, 2009
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Masaki Hamada, Hitoshi Fuji, Makoto Iwamura
  • Patent number: 7634653
    Abstract: An event-ordering certification system 100 includes a certification apparatus 1, a plurality of user apparatuses 2i (i=a, b, . . . , n), an audit apparatus 3 for performing an audit of an event-ordering receipt published by the certification apparatus 1 and a network 4 for connecting these elements with each other. In response to an event-ordering request from one user apparatus 2i, the certification apparatus 1 publishes the event-ordering receipt and sends it to the user apparatus 2i. If a mistrust is produced in the event-ordering receipt, the user apparatus 2i verifies the event-ordering receipt with the use of data published by the certification apparatus 1 and an audit result by the audit apparatus 3.
    Type: Grant
    Filed: August 18, 2005
    Date of Patent: December 15, 2009
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Eiichi Horita, Satoshi Ono, Hidetaka Ishimoto, Akira Takura
  • Publication number: 20090303486
    Abstract: A light source is provided that realizes a single spectral linewidth having a half value width of 1 MHz or less and that is not influenced by the ambient temperature. A light source includes first laser (71) generating first laser light, second laser (12) generating second laser light, and nonlinear optical crystal (13) wherein the first laser light and the second laser light are injected into the nonlinear optical crystal to generate coherent light by the generation of a difference frequency or a sum frequency. The second laser (12) is a wavelength-tunable light source that includes therein a diffraction grating and that can sweep the wavelength of the second laser light. The first laser (71) is composed of semiconductor laser and a fiber grating that has a reflection bandwidth narrower than a resonance wavelength spacing determined by the laser chip length of the semiconductor laser.
    Type: Application
    Filed: June 20, 2007
    Publication date: December 10, 2009
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Katsuaki Magari, Tsutomu Yanagawa, Toshiki Nishida, Osamu Tadanaga, Masaki Asobe, Takeshi Umeki, Hiroyuki Suzuki
  • Publication number: 20090304031
    Abstract: A digital signal demultiplexing apparatus for demultiplexing a received signal including a plurality of signals that are frequency-multiplexed to output demultiplexed signals is disclosed. The digital signal demultiplexing apparatus includes: demultiplexing filter bank means including a configuration in which unit demultiplexing filter banks are connected in a multistage manner, each unit demultiplexing filter bank including one or more filters for filtering an input signal and a down-sampler for down-sampling an output signal of each filter to output an down-sampled signal; and frequency conversion and decimator means configured to receive at least one of the received signal and output signals of each unit demultiplexing filter bank.
    Type: Application
    Filed: May 18, 2007
    Publication date: December 10, 2009
    Applicant: Nippon Telegraph and Telephone Corporation
    Inventors: Kiyoshi Kobayashi, Hiroshi Tanaka, Hiroshi Kazama
  • Publication number: 20090304162
    Abstract: To reduce the operations required by a user to perform user authentication using the user's communication apparatus, a call module (4d, 5d, 6d) acquires, upon receiving a user ID, a unique ID corresponding to the user ID and being of a user communication apparatus (11) by using a user ID matching list (4b, 5b, 6b), and also randomly selects one originating number with an originating number selector (4c, 5c, 6c). The call module (4d, 5d, 6d) makes a call with a predetermined number of rings to the user communication apparatus (11) having the unique ID corresponding to the user ID by using the selected originating number and via a system communication apparatus (13, 14, 15).
    Type: Application
    Filed: July 6, 2007
    Publication date: December 10, 2009
    Applicant: Nippon Telegraph and Telephone Corporation
    Inventors: Haruhiko Fujii, Tetsuya Nakagawa
  • Patent number: 7630649
    Abstract: An economical optical network is constituted by effectively using network resources by using the minimum number of, or minimum capacity of 3R repeaters. 3R section information corresponding to topology information on the optical network to which an optical node device itself belongs is stored, and the 3R section information stored is referred so as to autonomously determine whether or not the optical node device itself is an optical node device for implementing the 3R relay when setting an optical path passing through the optical node device itself. Alternatively, when the optical node device itself is a source node, another optical node device for implementing the 3R relay among the other optical node devices through which the optical path from the optical node device itself to the destination node passes is identified, and this identified optical node device is requested to implement the 3R relay when setting an optical path in which the optical node device itself is a source node.
    Type: Grant
    Filed: March 12, 2004
    Date of Patent: December 8, 2009
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Eiji Oki, Akira Misawa, Masaru Katayama, Satoru Okamoto
  • Publication number: 20090285137
    Abstract: A wireless transmitting apparatus inserts a training signal into a transmission burst at fixed symbol intervals as a pilot signal, a wireless receiving apparatus performs AD conversion of a received burst signal, performs symbol timing recovery, performs frame position detection and pilot signal extraction from the received burst signal for which symbol timing was established, performs frame synchronization, and performs a carrier frequency estimation using pilot signal. A carrier frequency estimation is also performed with respect to a received burst signal for which frame synchronization was established, and channel distortion is estimated and output based on a frequency-corrected received burst signal. Channel distortion estimation is then performed with respect to a frequency-corrected received burst signal, and a data symbol sequence of the channel-compensated received burst signal is converted to a received data bit stream.
    Type: Application
    Filed: September 5, 2006
    Publication date: November 19, 2009
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takafumi Fujita, Daisei Uchida, Yosuke Fujino, Osamu Kagami, Masahiro Umehira
  • Patent number: 7617238
    Abstract: A system management method is disclosed for associating a process object and a process with each node in a tree structure, and operating each node based on the tree structure so as to manage the process object and the process, including: registering a registered user that performs operations for a general node corresponding to the process object or for a function node corresponding to the process; setting the function node as a child node of the general node corresponding to the process object for which the process corresponding to the function node should be performed, and setting the general node as a parent node of the function node; setting registered user operation authority for each registered user; and, when execution of the process corresponding to the function node is requested by the registered user, causing the function node to execute the process only when the process is permitted by the registered user operation authority, of the registered user requesting the process, set in the general node tha
    Type: Grant
    Filed: July 9, 2004
    Date of Patent: November 10, 2009
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Jouji Nakayama, Tetsuya Yamamoto, Ken-ichiro Shimokura, Tsutomu Yabuuchi, Kimitaka Endo, Takashi Imaeda
  • Patent number: 7615192
    Abstract: A sensing element in which a dye that changes in the light absorption characteristic of the visible region upon reaction with ozone gas is deposited in the pores of a porous material is prepared. A change in dye before and after exposing the sensing element to a measurement environment for a predetermined time is measured. The ozone gas amount in measurement target air is measured on the basis of the change in dye.
    Type: Grant
    Filed: March 13, 2008
    Date of Patent: November 10, 2009
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Yasuko Maruo, Shigeo Ogawa, Seizou Sakata, Tohru Tanaka
  • Publication number: 20090273790
    Abstract: The present invention provides an OCT technique that permits tomographic observation of a biological body parts that is difficult to restrain and also provides a tomographic observation technique for the observation of a constrainable part that does not require constraint and remove the burden from biological body. A wavelength-tunable light generator (wavelength-tunable light source) is employed as the light source of the optical coherence tomography device. The wavelength-tunable light generator has a wave number tunable range width of at least 4.7×10?2 ?m?1 and an emitted-light frequency width of no more than 13 GHz, for example, and includes means capable of changing the wave number stepwise at wave number intervals of no more than 3.1×10?4 ?m?1 and time intervals of no more than 530 ?s.
    Type: Application
    Filed: June 15, 2009
    Publication date: November 5, 2009
    Applicants: SCHOOL JURIDICAL PERSON KITASATO INSTITUTE, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Kimiya SHIMIZU, Kohji OHBAYASHI, Takuji AMANO, Hideaki HIRO-OKA, DongHak CHOI, Hiroyuki FURUKAWA, Motoi NAKANISHI, Fumiyoshi KANO, Takeo MIYAZAWA, Ryoko YOSHIMURA
  • Publication number: 20090276325
    Abstract: A bid-opening device 20 receives from each bidding device 10m a bidding price index ?m=g(hk(IVm)) (where IVm is an initial value, hk indicates k-times processing with a one-way function h and g is a one-way function) and its identifier IDm. The received information is stored on a common bulletin board 25. Dm=hk(IVm) (where Dm=g(Dm) is generated with k set as the upper limit value K of the bidding price. The bulletin board 25 is checked for ?m which matches this Dm. If no match is found, m is incremented by one, and the check for ?m-Dm matching is made for each of m bidding devices. Upon completion of the matching for all the bidding devices, k is decremented by one, and a check is made for ?m which matches Dm=g(hk(IVm)), and the index k for which they match is determined as the highest price bid. The bid-opening device 20 outputs that k and the identifier IDm of ?m.
    Type: Application
    Filed: June 22, 2009
    Publication date: November 5, 2009
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Kunio Kobayashi, Hikaru Morita, Koutarou Suzuki