Patents Assigned to Nippon Telegraph and Telephone Corp.
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Patent number: 5263176Abstract: In a multi-station radio communications system wherein plural channels are accessible for communication between plural fixed stations and plural mobile units (viz., dynamic channel assignment) and wherein each of plural fixed stations selects a channel according to channel assignment priority data, the radio channels are grouped into a plurality of channel groups. The channels in each of the channel groups forms a numerically looped sequence of channels. The first channel of the numerically loop sequence in one channel group is different from the first channel of the numerically looped sequence in each of the other channel groups. Each of the plural fixed stations is set to select the channel having the highest priority or to select one of the first channel of the numerically looped sequence and a channel nearest to the first channel in the event that a plurality of channels have the same priority.Type: GrantFiled: February 8, 1991Date of Patent: November 16, 1993Assignees: NEC Corporation, Nippon Telegraph and Telephone Corp.Inventors: Susumu Kojima, Tetsuro Hanazawa
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Patent number: 5255308Abstract: In a wide area cordless telephone system, an individual-call signal is generated if an incoming call from the telephone network is an individual call to one of cordless stations of a group and a group-call signal is generated if it is directed to all cordless stations of the group. A group of access units are associated with the cordless station of each group to establish a control channel and speech channels with the cordless stations. The access units respond to the individual-call signal by transmitting a speech channel identifier to one of the cordless stations through the control channel and transmitting a ringing signal through a speech channel specified by the speech-channel identifier. In response to the group-call signal, speech-channel identifiers are successively transmitted from the access units to the cordless stations through the control channel and group ringing signals are respectively sent to the cordless stations through speech channels specified by the speech-channel identifiers.Type: GrantFiled: February 8, 1991Date of Patent: October 19, 1993Assignees: NEC Corporation, Nippon Telegraph and Telephone Corp.Inventors: Tadao Hashimoto, Kazushige Tanaka
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Patent number: 5244846Abstract: An optical functioning glass for enabling optical amplification at 1.3-.mu.m wavelength band or increasing efficiency of the amplification is disclosed. The optical functioning glass contains Nd.sup.3+ as an active material and uranium, both of which are doped in a multi-component function glass serving as a host glass. Since uranium is doped in the optical functioning glass, light emission of Nd.sup.3+ in the 1.06-.mu.m wavelength band can be absorbed by uranium. A decrease in efficiency of induced emission in a 1.3-.mu.m wavelength band can be prevented, and an optical functioning glass suitable for optical amplification in the 1.3-.mu.m wavelength band can be obtained. When a fiber is formed using the optical functioning glass as a core, a low-threshold, high-gain fiber amplifier, fiber laser, and the like can be obtained.Type: GrantFiled: February 3, 1992Date of Patent: September 14, 1993Assignees: Sumitomo Electric Industries, Ltd., Nippon Telegraph and Telephone Corp.Inventors: Masashi Onishi, Koji Nakazato, Hiroo Kanamori, Minoru Watanabe, Yoshiaki Miyajima
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Patent number: 5214728Abstract: A bi-directional optical communication system. A first optical fiber includes a plurality of pieces, each piece having a first and second end. An optical amplifier for amplifying optical signals transmitted in a first direction is coupled to first and second pieces of the first optical fiber. A second optical fiber is coupled to the first and second pieces, bypasses the optical amplifier and transmits optical signals in a second direction opposite to the first direction. A first optical signal generator apparatus coupled to the first piece of the first optical fiber provides optical signals propagating in the first direction to a optical receiver apparatus coupled to the second piece of the first optical fiber. A second optical signal generator in the optical receiver apparatus provides optical signals propagating in the second direction to the first optical signal generator apparatus.Type: GrantFiled: May 22, 1992Date of Patent: May 25, 1993Assignees: Sumitomo Electric Industries, Ltd., Nippon Telegraph and Telephone Corp.Inventors: Masayuki Shigematsu, Kohji Nakazato, Izumi Sankawa
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Patent number: 5202360Abstract: An adhesive composition comprising a photopolymerization initiator or curing agent and the compound represented by the formula (I) ##STR1## wherein M is a divalent organic group comprising at least one substituted or unsubstituted alicyclic hydrocarbon group or a divalent organic group comprising at least two substituted or unsubstituted aromatic hydrocarbon groups, the alicyclic hydrocarbon group or aromatic hydrocarbon group may be linked by O, S or CH.sub.2 or may form a condensed ring, n is zero or a positive number.Type: GrantFiled: July 29, 1991Date of Patent: April 13, 1993Assignees: Daiken Industries, Ltd., Nippon Telegraph & Telephone Corp.Inventors: Akira Ohmori, Yoshiki Shimizu, Motonobu Kubo, Kouzaburou Nakamura, Tohru Maruno, Norio Murata, Hideo Kobayashi
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Patent number: 5203024Abstract: An antenna selection diversity receiver system for TDM signals that switches antennas for every assigned time slot so that the best receive signal quality is obtained in the assigned time slot according to the prediction made by using the signal quality just before the assigned time slot. The prediction of signal quality is carried out according to the receive level (R.sub.1, R.sub.2), and the slope of the same of each of the antennas just before the assigned time slot. The signal quality may be determined by the average code error rate, receive level at the center of the assigned slot, or the minimum receive level in the assigned slot. The prediction is carried out either through linear prediction or non-linear prediction.Type: GrantFiled: April 25, 1991Date of Patent: April 13, 1993Assignee: Nippon Telegraph & Telephone Corp.Inventor: Yasushi Yamao
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Patent number: 5168715Abstract: A cooling apparatus includes a bypass provided to a path extending from a compressor to an expansion valve via a condenser, and a unit for controlling a ratio of a flow rate of a refrigerant of the path via the condenser to that of the bypass path, or a unit for varying an air volume of a fan of an outdoor unit for blowing the condenser so as to vary a capacity of the condenser. The degree of superheat of the refrigerant is measured at an exit of the evaporator, and an expansion valve is controlled in accordance with the measured degree of superheat.Type: GrantFiled: November 29, 1990Date of Patent: December 8, 1992Assignee: Nippon Telegraph and Telephone Corp.Inventors: Masaki Nakao, Kazuo Ohshima, Tsuneo Uekusa
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Patent number: 5166894Abstract: A method and an apparatus for the cell loss rate estimation in an integrated network, capable of highly accurate estimation which is not too small compared with the actual cell loss rate. In the apparatus, inputting probability density functions of number of arriving cells and an average number of arriving cells for a prescribed constant period of time; calculating a weighted sum of the probability density functions of number of arriving cells, using weight factors which depend on a buffer capacity of the output buffer and a link capacity of the integrated network; and obtaining an estimation value for the cell loss rate by dividing the weighted sum by the average number of arriving cells. These method and apparatus for the cell loss rate estimation are applied to a method and an apparatus for the call admission control as well as a method and an apparatus for the buffer/link capacity designing.Type: GrantFiled: November 15, 1990Date of Patent: November 24, 1992Assignee: Nippon Telegraph and Telephone Corp.Inventor: Hiroshi Saito
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Method and apparatus for creating and displaying navigators for guiding to related image information
Patent number: 5123088Abstract: Image information units, related with one another in the order of their magnitudes defined for each of a plurality of properties of each image, are prestored in an image information storage and management device. All image information units adjoiningly related by their properties with a main image being displayed on a display are read out of the image information storage and management device, and contracted images of the read-out image information units are displayed as navigators on the display screen, together with the main image.Type: GrantFiled: June 26, 1989Date of Patent: June 16, 1992Assignee: Nippon Telegraph and Telephone Corp.Inventors: Hisashi Kasahara, Hideki Koike, Tsutomu Horikoshi, Yoshinobu Tonomura, Tomio Kishimoto -
Patent number: 5080927Abstract: A thin film formation method includes the steps of holding a substrate in a reduced-pressure vapor phase reaction chamber having means for irradiating light in visible and ultraviolet ranges, supplying an organo-titanium compound containing a tri-azo group, and vapor-depositing a titanium nitride film on a surface of the substrate by an excitation reaction caused by light.Type: GrantFiled: July 6, 1990Date of Patent: January 14, 1992Assignee: Nippon Telegraph and Telephone Corp.Inventors: Koichi Ikeda, Masahiko Maeda, Yoshinobu Arita
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Patent number: 5081704Abstract: According to a method of arranging radio control channels in mobile communications, for covering a service area with a plurality of radio zones and causing base and mobile stations to exchange signals through the control channels, a broadcasting information transmission portion is assigned to the control channels. This broadcasting information is to be transmitted from the base station to each mobile station to broadcast information associated with radio zones. Information associated with control channel structure in units of base stations is broadcast to the broadcasting information transmission portion. A frequency and a time slot capable of causing the base station and the each mobile station to exchange the signals are determined on the basis of the pieces of broadcasting information and an identical number commonly recognized by the base and mobile stations.Type: GrantFiled: September 19, 1990Date of Patent: January 14, 1992Assignee: Nippon Telegraph & Telephone Corp.Inventors: Narumi Umeda, Onoe Seizo, Utano Takanori
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Patent number: 5067075Abstract: In a system comprising input/output devices, a memory and a control processor, direct memory access information (memory address and data) from an input/output device to the processor is stored temporarily and then a direct memory access request is transmitted to the processor. The processor bus holding time at direct memory access is reduced, and the processing speed of the processor is improved.Type: GrantFiled: May 10, 1988Date of Patent: November 19, 1991Assignees: Hitachi, Ltd., Nippon Telegraph & Telephone Corp.Inventors: Minoru Sugano, Akira Horiki, Zenichi Yashiro, Hironori Matsushima
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Patent number: 5049964Abstract: A bipolar transistor includes collector, base and emitter regions. The collector region consists of a first semiconductor region of a first conductivity type and formed in contact with a surface of a semiconductor layer. The base region consists of a second semiconductor region of a second conductivity type formed within the collector region to be in contact with the surface of the semiconductor layer. The emitter region consists of a third semiconductor region of the first conductivity type formed within the base region to be in contact with the surface of the semiconductor layer. The transistor also includes collector, base, and emitter electrodes. The collector and base electrodes are connected to the collector and base regions at opposite edges of a single opening formed in a field insulating film covering the surface of the semiconductor layer. The collector and base electrodes consist of a conductor. The emitter electrode is connected to the emitter region and consists of a conductor.Type: GrantFiled: March 22, 1990Date of Patent: September 17, 1991Assignee: Nippon Telegraph & Telephone Corp.Inventors: Tetsuchi Sakai, Yoshiji Kobayashi
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Patent number: 5036290Abstract: Synchrotron radiation is generated when a base of charged particles is bent by a bending magnet. The synchrotron radiation passes down a lead-out duct as the total number of pumps is limited by the size of the apparatus and many pumps are needed in order to achieve a good vacuum. An ion pump has a main magnetic field, normally generated by a magnet of the ion pump which controls the behavior of the electrons in the ion pump. However, the leakage magnetic field of the bending magnet affects the ion pump, and therefore the ion pump is arranged so that its main magnetic field is aligned with the leakage magnetic field at the ion pump, or at least with a main component thereof. In this way, the effect of the leakage magnetic field on the ion pump is reduced. Indeed, it is possible to use the leakage magnetic field as the main magnetic field of the ion pump.Type: GrantFiled: March 8, 1990Date of Patent: July 30, 1991Assignees: Hitachi, Ltd., Nippon Telegraph and Telephone Corp.Inventors: Tadasi Sonobe, Mamoru Katane, Takashi Ikeguchi, Manabu Matsumoto, Shinjiro Ueda, Toshiaki Kobari, Takao Takahashi, Toa Hayasaka, Toyoki Kitayama
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Patent number: 5032203Abstract: Polishing agent including as a main constituent an aqueous solution containing sodium bromite. The aqueous solution may further contain particles which are not dissolved in the solution or an alkali agent to adjust the pH to 8 to 14. Also the apparatus and method for polishing articles using the polishing agent are disclosed.Type: GrantFiled: January 4, 1989Date of Patent: July 16, 1991Assignees: Nippon Telegraph & Telephone Corp., Nippon Silica Industrial Co., Ltd.Inventors: Toshiroh K. Doy, Hiroshi Nakada, Yoshihiko Kunimitsu
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Patent number: 5016970Abstract: A ferrule for optical fibers transmitting linearly polarized light capable of preventing deterioration and fluctuation of the extinction ratio. The ferrule incorporates at least two paths connecting a region in a vicinity of an end of a puncture for an optical fiber inside the flange portion with outside of the ferrule. These paths effectively enable the removal of air in such a region which could have caused an extraneous stress on the optical fiber resulting in deterioration of the extinction ratio. An optical fiber connector using this ferrule is also disclosed.Type: GrantFiled: August 10, 1989Date of Patent: May 21, 1991Assignee: Nippon Telegraph and Telephone Corp.Inventors: Ryo Nagase, Juichi Noda, Etsuji Sugita
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Patent number: 4996496Abstract: In a bending magnet, a core which is substantially sectoral or semi-circular in horizontally sectional configuration and in which opposed magnetic poles are formed and a vacuum chamber for storage of a charged particle beam is disposed in a gap between the opposed magnetic poles, and a pair of upper and lower exciting coils for generating a bending magnetic field in the gap between the magnetic poles of core, the reluctance against the magnetic flux passing through a portion of the core adjacent to the inner circumference of the orbit of the charged particle beam and a portion of the core adjacent to the outer circumference of the charged particle beam orbit is equally uniformed over the overall length of the orbit of the charged particle beam.Type: GrantFiled: September 9, 1988Date of Patent: February 26, 1991Assignees: Hitachi, Ltd., Nippon Telegraph and Telephone Corp.Inventors: Masashi Kitamura, Takashi Kobayashi, Shunji Kakiuchi, Kiyoshi Yamaguchi, Hiroshi Tomeoku, Naoki Maki, Jyoji Nakata, Yasumichi Uno
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Patent number: 4973393Abstract: An aluminum film is formed on the surface of a substrate magnesium or magnesium alloy, and the resulting product is heated in a non-oxidizing or reducing gas having a high hydrostatic pressure at a temperature ranging from the eutectic point of the magnesium or magnesium alloy and the different metal to a temperature at or below which neither of the magnesium or magnesium alloy and the different metal is molten. This treatment provides a boundary layer between the aluminum film and the magnesium or magnesium alloy. This boundary layer is free from pinholes running from the interface of the aluminum film and the boundary layer to the magnesium or magnesium alloy ground. This surface-treated magnesium or magnesium alloy has excellent corrosion resistance surface electric conductivity, thermal conductivity and heat shock resistance.Type: GrantFiled: September 22, 1989Date of Patent: November 27, 1990Assignee: Nippon Telegraph and Telephone Corp.Inventors: Masato Mino, Goro Yamauchi, Kishio Arita
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Patent number: 4965558Abstract: An image retrieval system and method are provided for retrieving and displaying images of the plurality of images stored in the system. Images are grouped into collections of images, or documents. Representative images indicative of the representative images include representations of third, orthogonal or depth dimensions indicative of the number of images in the image groups. With a position indicating device, the user selects for display an image from an image group by indicating a position along the depth dimension of the representative image at a location corresponding to the relative location of the image in the image group. The image then is retrieved and displayed. Once the image is displayed, means are provided for sequential retrieval and display of images, forwards or backwards, through the images in the selected image group.Type: GrantFiled: July 15, 1987Date of Patent: October 23, 1990Assignees: Interand Corporation, Nippon Telegraph and Telephone Corp.Inventors: Yosinori Saki, Hiroshi Kotera, Kazuo Unemoto, Tomohiko Arikawa, Wayne Jung, Timothy Tutt, Mike Dunk
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Patent number: 4939785Abstract: In a radio communication network system for use in carrying out communication with a plurality of radio telephone sets in a service zone by the use of a control channel and a plurality of speech channels, a connecting equipment unit (CE) is selectively operable in cooperation with a radio control unit (RCU) in a speech mode of forming a speech path through a selected one of the speech channels and an additional mode of selectively monitoring the control and the speech channels. The additional mode may be divided into first and second control modes for allowing and rejecting reception of a call with the control channel monitored, respectively. Alternatively, either a rest mode or a combination of rest and initial program loading modes may be added to the additional mode. A plurality of the connecting equipment units may be located in a single service zone and selectively put into the speech and the additional modes with only one of the connecting equipment units kept in the first control mode.Type: GrantFiled: May 31, 1988Date of Patent: July 3, 1990Assignees: Nippon Telegraph and Telephone Corp., Matsushita Communication Industrial Co., Ltd., NEC Corp.Inventors: Yoshitoshi Murata, Masahiko Hirono, Toshihiko Shibata, Fumio Suzuki, Mitsuo Sato, Tadao Hashimoto