Patents Assigned to Nippon Telegraph & Telephone Corp.
  • Patent number: 6202379
    Abstract: The present invention provides a transformable linked structure, a deployable diagonal structure, a plane stowage-type deployable truss and a line stowage-type deployable truss with high rigidity and reliability constituted by the above-described transformable linked structure and the above-described deployable diagonal structure, and also provides a plane/line stowage truss structure extremely approximated to a spherical surface using the two types of deployable trusses. The present invention discloses a module linked structure for linking deployable trusses securely and a holding/releasing mechanism for realizing reliable holding and release. Further, the present invention provides a modular deployable antenna with high precision even if it is large-sized which is realized by spreading mesh on the plane/line stowage truss structure.
    Type: Grant
    Filed: July 22, 1998
    Date of Patent: March 20, 2001
    Assignee: Nippon Telegraph & Telephone Corp.
    Inventors: Akira Meguro, Jin Mitsugi, Kazuhide Ando
  • Patent number: 6185350
    Abstract: A mono-fiber type optical fiber cord comprising: a coated optical fiber which is an optical fiber with a fiber coat therearound, a synthetic resin coat having a substantially rectangular sectional surface for further covering the coated optical fiber, and a reinforcing member within the coat for coated optical fiber, wherein the reinforcing member is located along one of the shorter sides of the coat in the substantially parallel direction with the shorter sides in such a manner as to be embedded along the longitudinally extending direction of the coated optical fiber. An optical cord ribbon is formed by mutually bonding the longer sides of the adjacent substantially rectangular sectional surfaces of a plurality of the mono-fiber type optical fiber cords, and thereafter by coating the external surface of the thus aligned optical fiber cords by a bundling coating method.
    Type: Grant
    Filed: March 13, 2000
    Date of Patent: February 6, 2001
    Assignee: Nippon Telegraph and Telephone Corp.
    Inventors: Masao Tachikura, Hajime Takemoto, Shigenori Uruno, Isao Nakanishi
  • Patent number: 6107879
    Abstract: An automatic dynamic range control circuit is provided with a fixed-gain first circuit means and a variable-gain second circuit means having substantially the same propagation delay as the first circuit means. The automatic dynamic range control circuit holds the peak value of an input signal, selects the first circuit means when this peak value is smaller than a reference signal level, and selects the second circuit means when the peak value exceeds this reference signal level. When the held peak value is smaller than the reference signal level, the second circuit means is operated at the same gain relative to an input signal as the first circuit means by having its gain set by the reference signal. When the held peak value exceeds the reference signal, the gain of the second circuit means is limited by this held peak value and its output level is kept at or below a prescribed level.
    Type: Grant
    Filed: May 26, 1999
    Date of Patent: August 22, 2000
    Assignees: Nippon Telegraph & Telephone Corp., NTT Electronics Corp., Asahi Kasei Microsystems Co., Ltd.
    Inventors: Toshio Hoshino, Kazuhiro Daikoku, Kenji Yamada, Tomokazu Takasaki
  • Patent number: 6048986
    Abstract: A method for preparing aromatic compounds including 1,4-difluoropyromellitic dianhydride represented by formula (12): ##STR1## and 1,4-difluoropyromellitic acid represented by formula (15): ##STR2## by dehydrating or hydrolyzing and dehydrating precursors.
    Type: Grant
    Filed: June 17, 1998
    Date of Patent: April 11, 2000
    Assignee: Nippon Telegraph and Telephone Corp.
    Inventors: Shinji Ando, Toru Matsuura, Shigekuni Sasaki, Fumio Yamamoto
  • Patent number: 6032189
    Abstract: A network data distribution system which is operated, under circumstances affected by external or internal factors, without discontinuing a data distribution service while being adapted to the present situation is provided. In the server side of the system, data requested from a client are divided into packets, and packet data is formed by adding a time index, and in the client side, an amount of transmission or processing delay is calculated based on the time index included in the received packet data, and delay time information based on the calculated result is communicated. The server side selects the packet data to be next transmitted based on the communicated delay time information, and sends the selected packet data.
    Type: Grant
    Filed: February 5, 1997
    Date of Patent: February 29, 2000
    Assignee: Nippon Telegraph and Telephone Corp.
    Inventors: Hiroshi Jinzenji, Tatsuaki Ito, Tetsuo Tajiri
  • Patent number: 6005977
    Abstract: The present invention provides an image matching method which allows non-ear image positional shifts to be corrected on a real time basis, and an economical product testing system using this method. A two dimensional test image, consisting of pixels arranged as a matrix of bits distributed in both the vertical direction and the horizontal scanning direction, and an associated reference image are subjected to template matching at a cell matching arithmetic unit for each of line blocks consisting of a plurality of scan lines. The result of the template matching are quantitatively evaluated at an evaluation unit as being good or bad, and positional shifts are sequentially computed according to good evaluation results. Based on the positional shifts thus obtained, the comparative pixel addresses are accordingly corrected before the two images are compared at the comparator.
    Type: Grant
    Filed: July 17, 1996
    Date of Patent: December 21, 1999
    Assignee: Nippon Telegraph & Telephone Corp. N.T.T. Fanet Systems Corp.
    Inventors: Katsuyuki Tanimizu, Akira Shindo, Masakatsu Nunotani, Tetsuya Yamamoto
  • Patent number: 6004675
    Abstract: A coated glass fiber for light transmission consisting of a glass fiber for light transmission and at least one coating layer made of a UV-curing resin, wherein an outermost layer of the coating layer is made of a UV-curing resin having a Young's modulus of at least 100 kg/mm.sup.2 and a change of a cure shrinkage degree of 1% or less after a Young's modulus reaches one tenth of an end Young's modulus, which has good lateral pressure characteristics and low transmission loss.
    Type: Grant
    Filed: September 1, 1992
    Date of Patent: December 21, 1999
    Assignees: Sumitomo Electric Industries, Ltd., Nippon Telegraph & Telephone Corp.
    Inventors: Nobuhiro Akasaka, Tatsuya Kakuta, Kohei Kobayashi, Yasuo Matsuda, Shigeru Tomita
  • Patent number: 5973575
    Abstract: A voltage controlled oscillator for wide tuning range of frequency with less phase noise has a bipolar transistor provided with a positive feedback circuit between a base and an emitter of the transistor, an impedance matching circuit coupled with a collector of the transistor and an output terminal, a resistor coupled between the base of the transistor and a control source which provides control voltage for adjusting oscillation frequency of the oscillator. The base of the transistor shows capacitive negative impedance, and an inductive element is coupled with the base of the transistor for oscillation. The emitter of the transistor is grounded for D.C. voltage through an inductor or a transmission line, or coupled with a control voltage.
    Type: Grant
    Filed: February 12, 1998
    Date of Patent: October 26, 1999
    Assignee: Nippon Telegraph and Telephone Corp.
    Inventors: Kenji Kamogawa, Kenjiro Nishikawa, Ichihiko Toyoda, Tsuneo Tokumitsu
  • Patent number: 5936794
    Abstract: A media library system capable of carrying out an access to each recording medium in very short time. A media exchange operation is controlled such that the storage cells of the storehouse are divided into at least two groups arranged in an order of average distances with respect to the media drive, including a first group with a shortest average distance with respect to the media drive, and when the previously used recording medium was mounted on the media drive from the first group, the previously used recording medium is stored in the first group, whereas when the previously used recording medium was mounted on the media drive from one group other than the first group, one recording medium with a lowest utilization frequency among an adjacent group of that one group having a shorter average distance with respect to the media drive than that one group is moved from that adjacent group to that one group and then the previously used recording medium is stored in that adjacent group.
    Type: Grant
    Filed: October 17, 1995
    Date of Patent: August 10, 1999
    Assignee: Nippon Telegraph & Telephone Corp.
    Inventors: Makoto Mizukami, Nobuyoshi Izawa, Kikuji Katoh, Yoshihiro Isomura, Yoshihiro Sako
  • Patent number: 5901229
    Abstract: In an electronic cash implementing method using a trustee, a user registers his identification information ID.sub.U and anonymous public key N with the trustee and receives a license (B,I). The user processes the license (B,I) by a public key corresponding to the amount to be issued and sends the processed information to a bank to have it attach a blind signature to the information so that the user obtain electronic cash C from the blind signature. The user transmits to a shop the information B,I,C,N and a digital signature that assures the divisional use of the electronic cash. The shop verifies the validity of the information B and C and accepts it as cash and sends a history H of communication with the user to the bank and receives a payment therefrom.
    Type: Grant
    Filed: November 4, 1996
    Date of Patent: May 4, 1999
    Assignee: Nippon Telegraph and Telephone Corp.
    Inventors: Eiichiro Fujisaki, Tatsuaki Okamoto, Kazuo Ohta
  • Patent number: 5892894
    Abstract: A data re-transmission management scheme capable of improving the communication efficiency. In a data re-transmission from a server to a plurality of terminals through a communication network, any abnormal terminal including a busy terminal and/or a poor performance terminal among the plurality of terminals is detected, and each abnormal terminal is managed separately from other normal terminals, at the server. A management of data transmission and re-transmission from the server to the normal terminals is carried out first, and then a management of a re-transmission of only unreceived data of each abnormal terminal from the server to each abnormal terminal is carried out, after a completion of the data transmission and re-transmission with respect to the normal terminals.
    Type: Grant
    Filed: December 6, 1996
    Date of Patent: April 6, 1999
    Assignee: Nippon Telegraph & Telephone Corp.
    Inventors: Teruji Shiroshita, Osamu Takahashi, Masahide Yamashita
  • Patent number: 5887110
    Abstract: A video data playback system for reproducing requested video data by switching coded video data to be reproduced between normal playback coded video data and fast playback coded video data according to a requested playback mode, where the normal playback coded video data are encoded by a first video coding scheme using both intra-frame coding and inter-frame coding, while the fast playback coded video data are encoded by a second video coding scheme using only intra-frame coding and having a playback bit rate and a frame rate identical to those of the normal playback coded video data. The normal playback coded video data can be obtained by encoding the original video data first, then the fast playback coded video data can be obtained by encoding selectively decoded normal playback coded video data. Alternatively, the normal and fast playback coded video data can be obtained by synchronizing start and end of encoding by the first video coding scheme and encoding by the second video coding scheme.
    Type: Grant
    Filed: March 28, 1996
    Date of Patent: March 23, 1999
    Assignee: Nippon Telegraph & Telephone Corp.
    Inventors: Hideki Sakamoto, Tomoaki Kawaguchi, Hideharu Suzuki, Tatsuo Mori, Hiroyuki Kimiyama, Kazutoshi Nishimura, Kouichi Itoh, Mitsuru Maruyama, Hiroshi Sugiyama, Akira Uemori, Kazuo Okada
  • Patent number: 5885229
    Abstract: According to the present invention, two-dimensional pressure distribution associated with walking are collected at a preselected time interval as time series pressure distribution images, superposed images are formed by superposing the time series pressure distribution images in a time direction, a plurality of foot pressure mass regions are extracted from the superposed images, correspondence of each foot pressure mass region to the time series pressure distribution images are detected, feature parameters associated with the walking are detected based on the correspondence, and the feature parameters are displayed or printed.
    Type: Grant
    Filed: July 19, 1996
    Date of Patent: March 23, 1999
    Assignee: Nippon Telegraph & Telephone Corp.
    Inventors: Junji Yamato, Kyoko Sudo, Akira Tomono, Masanobu Arai
  • Patent number: 5880169
    Abstract: The invention provides a novel sulfonium salt having at least one acid labile group attached to a phenyl group in a molecule and a normal, branched or cyclic C.sub.1 -C.sub.20 alkylsulfonate anion. The novel sulfonium salt is effective for increasing the dissolution contrast between exposed and unexposed areas. Upon exposure, it generates an alkylsulfonic acid which is a weak acid, minimizing the influence of side reaction and deactivation during PEB step. The sulfonium salt is useful in a chemically amplified positive resist composition which lends itself to fine patterning and features high resolution.
    Type: Grant
    Filed: November 1, 1996
    Date of Patent: March 9, 1999
    Assignees: Shin-Etsu Chemical Co., Ltd., Nippon Telegraph and Telephone Corp.
    Inventors: Yoichi Osawa, Satoshi Watanabe, Katsuya Takemura, Shigehiro Nagura, Akinobu Tanaka, Yoshio Kawai
  • Patent number: 5862282
    Abstract: An optical connector that can stably connect even a tension-resistant jacket-covered optical fiber cord is provided. In an optical connector, which includes an optical connector plug 10 having a ferrule 14 holding an optical fiber and a housing 16 accommodating the ferrule, and an adapter connecting the optical connector plugs; the optical fiber is an optical fiber cord 12 in which at least the jacket carries tension, a secondary coated optical fiber (120) and the jacket (123) carrying the tension of the optical fiber cord 12 are secured to the ferrule 14, and the ferrule 14 is immovably mounted to the housing 16.
    Type: Grant
    Filed: June 17, 1997
    Date of Patent: January 19, 1999
    Assignees: Sumitomo Electric Industries, Ltd., Nippon Telegraph and Telephone Corp.
    Inventors: Ichiro Matsuura, Tomohiko Ueda, Toru Yamanishi, Shinji Nagasawa
  • Patent number: 5856561
    Abstract: Novel bisphenol carboxylic acid tertiary ester derivatives having two aromatic ether groups and an ester group which are all replaced by acid labile groups are provided. The derivatives are used as a dissolution inhibitor in a chemically amplified positive resist composition comprising an organic solvent, an alkali soluble resin, and a photo-acid generator. Since the dissolution inhibitor has a highly reactive acetal group as an acid labile group, its coupling-off rapidly takes place after exposure. The dissolution inhibitor itself is less alkali soluble and its acid decomposition product is a phenol derivative having a carboxylic acid group with high alkali solubility, leading to a high dissolution contrast.
    Type: Grant
    Filed: September 17, 1996
    Date of Patent: January 5, 1999
    Assignees: Shin-Etsu Chemical Co., Ltd., Nippon Telegraph and Telephone Corp.
    Inventors: Takesi Nagata, Satoshi Watanabe, Katsuya Takemura, Tsunehiro Nishi, Shigehiro Nagura, Akinobu Tanaka, Yoshio Kawai
  • Patent number: 5828654
    Abstract: In an input cell policing method in a network of an asynchronous transfer mode, according to information contained in a header field of each input cell, a group to which the cell belongs is identified. For each group, there are set a plurality of time frames having a predetermined length and mutually different phases to count the number of input cells in each time frame period. For each time frame, the count value of input cells is compared with a predetermined threshold value. An input cell for which the count value exceeds the threshold value in either one of the time frames is assumed to be an excess cell. The excess cell is discarded or a violation mark is added thereto.
    Type: Grant
    Filed: May 24, 1996
    Date of Patent: October 27, 1998
    Assignees: Hitachi, Ltd., Nippon Telegraph & Telephone Corp.
    Inventors: Akihiko Takase, Shigeo Shinada, Mitsuhiro Takano, Toshiya Oouchi, Naoaki Yamanaka, Youichi Sato
  • Patent number: 5824824
    Abstract: The invention provides a novel sulfonium salt having at least one acid labile group attached to a phenyl group in a molecule and a C.sub.2 -C.sub.20 alkylsulfonate or arylsulfonate anion whose alkyl or aryl has as a substituent an electron withdrawing group such as fluorine and nitro group. The novel sulfonium salt is effective for increasing the dissolution contrast between exposed and unexposed areas. Upon exposure, it generates a substituted alkyl or arylsulfonic acid which is a weak acid, minimizing the influence of side reaction and deactivation during PEB step. The sulfonium salt is useful in a chemically amplified positive resist composition which lends itself to fine patterning and features high resolution.
    Type: Grant
    Filed: November 1, 1996
    Date of Patent: October 20, 1998
    Assignees: Shin-Etsu Chemical Co., Ltd., Nippon Telegraph and Telephone Corp.
    Inventors: Yoichi Osawa, Satoshi Watanabe, Kaysuya Takemura, Shigehiro Nagura, Akinobu Tanaka, Yoshio Kawai
  • Patent number: 5825311
    Abstract: Representative vectors z.sub.1i and z.sub.2j are selected from codebooks CB1 and CB1, respetively, and multiplied by weighting coefficient vectors w.sub.1 and w.sub.2 of the same number of dimensions as those of the representative vectors, whereby weighted representative vectors z.sub.1i w.sub.1 and z.sub.2j w.sub.2 are generated. These weighted representative vectors are vector combined into a combined vector y.sub.ij, and a combination of the representative vectors is selected by a control part in such a manner as to minimize the distance between the combined vector y.sub.ij and an input vector X. The weighting coefficient vectors w.sub.1 and w.sub.2 each have a maximum component in a different dimension and are selected so that the sum of diagonal matrixes W.sub.1 and W.sub.2 using components of the weighting coefficient vectors as their diagonal elements becomes a constant multiple of the unit matrix.
    Type: Grant
    Filed: April 23, 1997
    Date of Patent: October 20, 1998
    Assignee: Nippon Telegraph and Telephone Corp.
    Inventors: Akitoshi Kataoka, Jotaro Ikedo
  • Patent number: 5818096
    Abstract: A pin photodiode having a structure capable improving the frequency response and the saturation output while maintaining the effective internal quantum efficiency and CR time constant. A pin photodiode is formed by: a first semiconductor layer in a first conduction type; a second semiconductor layer in a second conduction type; a third semiconductor layer sandwiched between the first and second semiconductor layers, having a doping concentration lower than those of the first and second semiconductor layers; a fourth semiconductor layer in the first conduction type, provided at one side of the first semiconductor layer opposite to a side at which the third semiconductor layer is provided; and a cathode electrode and an anode electrode connected directly or indirectly to the second semiconductor layer and the fourth semiconductor layer, respectively.
    Type: Grant
    Filed: April 3, 1997
    Date of Patent: October 6, 1998
    Assignee: Nippon Telegraph and Telephone Corp.
    Inventors: Tadao Ishibashi, Tomofumi Furuta, Naofumi Shimizu, Koichi Nagata, Yutaka Matsuoka, Masaaki Tomizawa