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The National Institutes for Quantum Science and Technology (QST) has been developing new cryogenic structural materials, such as JJ1 stainless, and nitrogen-enhanced 316L stainless, known as 316LN, since the 1980s for increased tensile strength to comply with the ITER requirements. QST has also developed prediction curves for yield stress and tensile strength at temperatures from room temperature to 4 K based on the actual properties of these materials at room temperature to reduce the number of tensile tests conducted at 4 K, which are costly. After material trials and qualifications, the manufacture of material candidates began in earnest from 2012. In total, over 2400 materials (over 5000 tonne) were manufactured by six fabricators until manufacturing was completed successfully in 2020. The material properties of each material candidate were evaluated by QST and added into a database registry. Sampling tests, e.g., tensile tests were conducted at 4 K and 77 K. The correlations between the mechanical and material properties were evaluated to optimize material specifications of future superconducting magnets. The accuracy of QST’s prediction curves was also confirmed. This paper summarizes the evaluation of the material properties and the prediction accuracy of mass-produced materials for the ITER toroidal field coil cases.

This paper proposes a test facility for micro hydraulic generation system. Micro hydraulic generation system is very difficult to exam their characteristics including hydraulic turbine because water flow in various conditions is necessary but it is very difficult to realize in laboratory. In this paper water flow is realized using general purpose pump that can add pressure to water flow to simulate water drop. From obtained experimental results, a simulation model of hydro turbine was built in order to establish high efficiency control system.

Plunging of metal pin or shaft into small hole inducing longitudinal vibration on static plunging force is studied. When inserting pin or shaft using only static force, the material with holes happen to broken by plunging pin by large static force and also the motor shaft plunged into the rotor center has inevitably eccentricity and must to adjust the eccentricity by manual or some machines. Using ultrasonic vibration, static force and eccentricity can be decreased due to decreasing frictional force by vibration.

This paper proposes a new learning method based on a state machine using 2-link manipulator robot. The motion symbols, which decide the robot motion, are generated by the state machine as the time series data. Using this method, the robot can achieve complicated tasks, for example, underactuated robots are controlled. This method is verified by the simulation.

Deep manned submersible ldquoSHINKAI 6500rdquo was built in 1989, and has been operated by Japan Agency for Marine-Earth Science and Technology (JAMSTEC). She has capability to dive down to 6500 m depth. Currently, she made 1097 dives until the end of July 2008. A round hatch on the top of the pressure hull is designed to constitute a part of the spherical pressure hull, and is very important structure to keep atmospheric pressure and waterproof in the hull. Therefore, we handle a hatch carefully in every operation, and moreover, we remove a hatch from the pressure hull at the time of the annual-maintenance and are doing the careful overhaul which involves the measurement and exchange of components. The number of her diving exceeded 1000 times, and she will reach 20 years old shortly. As consideration for that, an operation team, an engineering division and a ship builder implemented investigation for reconfirmation about soundness and safety of the pressure hull including a hatch. In this report, the result of investigation and evaluation about behavior of a hatch including the pressure hull is described.

This paper proposes a two-step noise suppression method in the frequency and time domains for frequency domain channel estimation in single-carrier (SC)-FDMA radio access using a variable transmission bandwidth. In the proposed method, a weighted coherent averaging filter suppresses the noise component of the estimated channel gain in the frequency domain and then, after conversion of the channel gain into a time domain signal, effective path selection with threshold detection suppresses the noise component further. Computer simulation results show that the channel estimation with weighted coherent averaging in the frequency domain in addition to path selection employing threshold detection in the time domain improves the block error rate (BLER) by approximately 0.5 dB compared to that with path selection in the time domain only when the transmission bandwidth is one resource block (RB), i.e., 180 kHz, to four RBs, where paths are not sufficiently resolved. We also confirm that frequency domain channel estimation using only the threshold based path selection improves the BLER performance the most in a wide transmission bandwidth such as 25 RBs where sufficient path resolution accuracy is obtained.

An evanescent-wave laser absorption technique using an optical waveguide has been developed to measure the density of the metastable atoms in the vicinity of the barrier surface in a plane parallel barrier gas discharge. The optical waveguide on the surface of barrier material, LiNbO 3 crystal, is produced by a proton exchange in an H 2 PO 4 solution. A property of an optical transmission in the waveguide is checked experimentally and light with three TM-modes can propagate in the waveguide. The waveguide depth is estimated to be about 0.88 μm. The LiNbO 3 with the waveguide is utilized as one dielectric of a barrier discharge and the matastable density existing in the penetration depth of evanescent-wave from the surface, 50 nm, is directly measured from the absorption signal. The surface density is measured at various gas pressures of Ar and frequencies of pulsed voltage applied from a power supply. The surface density is also compared with the density in the bulk plasma.

Manned deep submersible "Shinkai 6500", which has a depth capability of 6500 m, was developed in 1989 by JAMSTEC. She is the deepest manned submersible in the world. Since the operation started in 1990, she contributed to science investigation over 18 years. The Shinkai 6500 achieved 1000th dive in March 2008. She made dives in the trench area around Japan, in the Eastern Pacific Ocean, in the Indian Ocean, in the Atlantic Ocean, and etc. Various investigations on deep sea biology and microbiology in extreme environment, earthquake or volcanic activity etc. have been carried out using the advantage of her depth capability. In this report, the history and the operation of "Shinkai 6500" will be introduced.

In this paper, a power conditioner that can generate power into the utility from a 10 kW windmill is introduced and developed. This equipment utilized inexpensive diode rectifier plus boost converter in the first stage and V-connection type inverter that has the merit of using high DC voltage in the next stage. The operation of this equipment was verified, the characteristics were evaluated and the practicability was confirmed experimentally. The equipment is deployed with ground fault detection function, and because of the transformer-less utility, it is efficient and has the advantage of generating less loss compared to its counterpart.

SOFCs have a potential of showing extraordinarily high electric conversion efficiency. Thus they are considered as promising candidates for future distributed generators. However operations of SOFCs are not simple compared with the other generators such as gas engines or gas turbine since SOFCs have to be operated at a high temperature. It is difficult to start up SOFCs rapidly and thus they are not suitable for situations where there is a large fluctuation of demand. This limits the application of SOFCs and the introduction is restricted within a narrow market. In order to promote the introduction of SOFCs to a market, how to make use of SOFCs is a very significant factor. Techniques to operate and control SOFCs are key factors to draw the potential of SOFCs. Therefore information technologies are expected as a powerful tool to improve the total performance of SOFCs.

This paper describes an attempt to transform a 3D model of a person's face to produce an intended change of impression. 3D shape and surface texture of faces are represented by high-dimensional vectors automatically extracted from the 3D data captured by a range finder, and variations among a set of faces are coded by applying principal component analysis. The relationship between the coded representation and the attribute of faces along a given impression dimension is analyzed to obtain an impression transfer vector. Here, we propose a method using this impression transfer vector to manipulate 3D faces in order to transform impressions. Experimental results on transformation of gender impressions confirmed the superiority of manipulating the 3D information of faces over a previous approach using only 2D face information.

In this paper, we study the MAC access delay of EDCA in the draft IEEE 802.11e standard under saturated conditions. We obtain explicit expressions for the mean, the standard deviation and the generating function of the distribution of the access delay. By using numerical inversion on the generating function, we are able to compute values of the distribution. We show that our analytical model has high accuracy via comparison with simulation

High cost-peformance production of ASICs is achieved when the super operator shift method is applied to an ASIC line using a newly developed scheduler with operator level and wafer-level scheduling functions.

Deep Submergence Vehicle Shinkai 6500, owned and operated by Independent Administrative Institution Japan Agency for Marine-Earth Science and Technology (hereafter JAMSTEC, and JAMSTEC was reorganized from Japan Marine Science and Technology Center on April 1, 2004), is the deepest manned submersible in the world. Shinkai 6500 has a depth capability of 6500 m and was developed in 1989 by JAMSTEC, and Mitsubishi Heavy Industries, Ltd. (hereafter MHI). She was commissioned in 1990 with her exclusive support vessel "YOKOSUKA" (length overall; 105 m, gross tonnage; 4,436 GT). Shinkai 6500 has dived 811 times until the end of March 2004. The major dives were carried out in the East Pacific Raise, the Mid Atlantic Ridge, the Indian Ocean and the western Pacific region, including the Mariana Trench and the Japan Trench. She has achieved many fruitful and important scientific results for the science in the world. The original power source of Shinkai 6500 was oil filled pressure compensated silver oxide zinc battery. However, the silver-zinc battery is very expensive, has short life, and is necessary complex work for maintenance. The operators needed to do full electric discharge every 15th dive, and to adjust electrolysis liquid after 30 dives. In order to supply electricity for the Shinkai 6500, two 400Ah battery pods, 800Ah in total, are installed. From 1997, the JAMSTEC Shinkai 6500 operation team, and MHI and Japan Storage Battery Co. Ltd started to develop the 400Ah capacity oil filled pressure compensated lithium-ion battery for Shinkai 6500 main batteries. And we completed development and sea trial in March 2004. The advantage of lithium ion battery in comparison with silver zinc battery is (1) maintenance-free, it is not necessary to do adjustment of electrolysis liquid. (2) long life time, the battery life time increased from 75 times or 1 year, to 180 times or 2 years, and (3) light weight, it is about 100 kg lighter than the silver zinc battery system. We will development and result of operation of introduce the first big capacity oil filled pressure compensated lithium ion battery for the Shinkai 6500.

This paper proposes an accurate inspection technique of fabric defects in an electromagnetic wave shield mesh of the plasma display panel (PDP-mesh) for automatic detection. The proposed method utilizes two-dimensional discrete Fourier transform (DFT) and a Gabor filter for accurate detection. The DFT of the whole image enables the user to detect global defects, such as yarn density and yarn orientation, of the manufactured PDP-mesh. The determined global features can be utilized to design the optimum Gabor filter to detect the local defects such as clogging, yarn lack, and yarn slippage. Defective areas can be extracted from the output of the Gabor filter by using a variable threshold method. Experimental results show that the proposed method can accurately detect the defects from scanned PDP-mesh images

This paper proposes an accurate inspection technique of fabric defects in an electromagnetic wave shield mesh of the plasma display panel (PDP-mesh) for automatic detection. The proposed method utilizes two-dimensional discrete Fourier transform (DFT) and a Gabor filter for accurate detection. The DFT of the whole image enables the user to detect global defects, such as yarn density and yarn orientation, of the manufactured PDP-mesh. The determined global features can be utilized to design the optimum Gabor filter to detect the local defects such as clogging, yarn lack, and yarn slippage. Defective areas can be extracted from the output of the Gabor filter by using a variable threshold method. Experimental results show that the proposed method can accurately detect the defects from scanned PDP-mesh images.

Sea surface temperature (SST) retrieved from the Advanced Microwave Scanning Radiometer for EOS (AMSR-E) aboard NASA Aqua is used as operational data source for monitoring oceanic conditions conducted by the Japan Meteorological Agency, and monitoring fisheries conditions conducted by the Japan Fisheries Information Service Center. In this paper, evaluation of AMSR-E SST accuracy is presented, and those SST applications are reported

A scheme to emulate leakage current of low threshold voltage MOSFETs using high threshold voltage MOSFETs is proposed. The leakage current at any threshold voltage lower than the original threshold voltage can be emulated without any changes in the manufacturing process. Furthermore, a single test structure can be used to measure the subthreshold leakage current at various threshold voltages. The DIBL (Drain Induced Barrier Lowering), source control, and substrate bias effects can be reproduced by the scheme. A test chip is manufactured and measured to show the validity of the proposed leakage emulator.

Treatment of sulfur dioxide (SO/sub 2/) has been studied using a pulsed, intense relativistic electron beam (PIREB). The dependence of SO/sub 2/ concentration and the removal efficiency of SO/sub 2/ on the number of PIREB irradiation have been investigated within a distant gas chamber spatially isolated from the electron beam source. The distant gas chamber is filled up with a dry-air-balanced SO/sub 2/ gas mixture with the pressure of 270 kPa, and is irradiated by the PIREB (/spl sim/2 MeV, /spl sim/100 A, /spl sim/60 ns) passing through a 1.6-m-long atmosphere. With the initial SO/sub 2/ concentration of 100 ppm, /spl sim/60% of SO/sub 2/ is successfully treated by firing 10 shots of PIREB irradiation. The SO/sub 2/ removal efficiency has been found to be 3-37 g/kWh. We have also found that a certain amount of NO/sub 2/ is produced by irradiation of the PIREB.

The major electric power companies in Japan celebrated their 50th anniversary in 2001. As the privately owned and virtually integrated utility companies, we constructed much infrastructure for generation, transmission and distribution. We have developed new technologies for the rapid growth of demanded power, which reached about 20 times of the initial value in a half-century. After full growth, saturation of the power growth comes to Japanese power industry. Following the deregulation of power generation, deregulation of retail started in 2000, and the new scheme for the free market is under discussion in the governmental committees. In this presentation, I would like to talk about the present status and future prospect of infrastructure in Japan and related R&D work, such as HVDC transmission, UHV transmission etc.

The electronic/optical hybrid network deploys the integration of optical GMPLS technology and IPv6 routing technology [J. Murayama, Aug. 2003]. This hybrid network improves the scalability from the viewpoint of the number of PE (provider edge) routers. Additionally, a high performance of packet forwarding is also respected. To improve forwarding performance of this network, a cut-through optical path that directly connects a pair of PE routers with high traffic demand is provided. This path improves a performance of packet forwarding between the PE routers, and avoids traffic congestion at electronic P (provider) routers. Since a number of cut-through optical paths are limited according to a limitation of network resources, a cut-through optical path should be assigned efficiently. This paper proposes an optimum path allocation algorithm according to traffic demand and resource limitation. On the other hand, to keep a best forwarding performance even if traffic demand changes, the reassignment of cut-through optical paths is needed. Such a reassignment could degrade quality of packet forwarding because a traffic concentration at an electronic P router is caused at a substituting time. This paper proposes a traffic control mechanism to avoid a traffic concentration at an electronic P router. To control a constant traffic concentration, we propose a load balancing method between electronic P routers. To control a temporal traffic concentration, we propose a cooperative operation between a cut-through optical path reassignment and IPv6 path assignment. This paper proposes a multi-layered traffic engineering server (MLTES) that provides the proposed functions and manages optical paths and IPv6 paths cooperatively and efficiently. MLTES achieves a high performance of an electronic/optical hybrid network, and provides a low cost and high performance IP-VPN platform.

The water surfaces detected by a conventional intensity based method from JERS-1 SAR images do not always coincide with the flood-damaged areas especially existing paddy fields. The authors propose morphological methods as spatial information. The result roughly agree with the reported flood-inundated areas. We concluded that this kind of methods has an advantage of the disaster monitoring using SAR satellite.

Removal of NO/sub x/ has been studied using both pulsed, intense relativistic electron beam (IREB) and pulsed corona discharge. The dependence of NO/sub x/ concentration and the removal efficiency of NO/sub x/ on the number of IREB shot have been investigated within a distant gas chamber spatially isolated from the electron beam source. In the pulsed corona-discharge experiment, an SI-thyristor has been used in the pulsed power generator.

This paper describes the development of a protocol transfer module for universal serial bus interface version 2.0 USB2.0-to-IEEE 1394 interface using synchronous packet control for audio and video (AV) data streams. This protocol transfer module can easily transmit AV data streams from a personal computer (PC) embedded USB2.0 interface port to a digital video camcorder (DVC) unless the AV data stream unsynchronizes between the USB2.0 and IEEE 1394 interfaces. This protocol transfer module is used for transmitting and editing AV data streams on PC and AV consumer appliances standardized with IEEE 1394. USB2.0 and IEEE 1394 interfaces are largely used for consumer electronics appliances especially home network devices. This protocol transfer module is used for AV consumer appliances standardized with IEEE 1394.

A fully automated method of extracting narrow rivers in tropical rain forests from JERS-1 SAR images was implemented using both spectral and spatial information. The system was divided into extraction of narrow rivers that appear as a series of line-like blobs and extraction of wide rivers that appear as dark continuous line-like features. The method was assessed by comparing the results from optical JERS-1 VNIR data and by applying 21 scenes in other areas in Amazon basin and Congo basin.

In a mountainous and highly populated country like Japan, corner reflectors frequently must be placed near confounding objects. A procedure to detect singular corner reflectors in such situations is described. It is found that the initial reduction of speckle by the Enhanced SFP filter greatly facilitated the detection of these corner reflectors from both JERS-1 SAR images and ERS-2 images.

Evaluates the effectiveness of several speckle reduction filters in extracting small/thin features in SAR images. The filters were tested on various types of bright and dark features in observed images instead of simulated images. The filters were required to preserve contrast between the feature and its immediate background, as well as reduce speckle in the image. Based on the results of the tests, the authors found that the Small Feature Preserving (SFP) filter was best for extracting bright features, and that the Sigma filter was best for extracting dark features.

In order to obtain more precise and quantitative crustal deformations, we combine the results of spaceborne differential interferometric synthetic aperture radar (D-InSAR), with the dense distribution of continuous Global Positioning System (GPS) observations, precise gravity measurements, and leveling surveys in the Tokai region, where dense and continuous geophysical and geochemical monitoring has been carried out due to the expected huge interplate earthquake. Seasonal uplift-subsidence motions of 2 to 6 cm are obtained from winter to the beginning of summer for both 1995 and 1997, that might be concordant with the leveling survey, although the atmospheric effects should play an important role for these conclusions. At the Sagara corner reflector, we have experimentally sifted the surface of the reflector and obtained fairly reasonable results, although the discrepancy of about 1.5 cm (along the line of sight) between theoretical estimate could be attributed to the unexpected contamination of noise from the surroundings and/or analytical processes.

A power system failure occurred at 1:19 p.m. on July 23, 1987, in the service area of the Tokyo Electric Power Company Inc. The unusually hot weather led to concentrated mass consumption of electricity, causing a failure which affected 2.8 million customers in the area. There were three major causes of this failure: the power demand level on that day was unusually high; the rate of demand increase exceeded previous levels; and air conditioners which have characteristics such that a fall in voltage leads to a rise in current are in widespread use in Japan. The failure is analysed and countermeasures to mitigate future power failures are presented. >

At the LSI process development stage, fabrication, and evaluation of a test element group (TEG) are repeatedly carried out to obtain optimum fabrication conditions. A high-speed TEG evaluation system was developed. By combining (1) a high-speed database with suitable indexes formed on a database machine, (2) a means of inputting data in parallel with measurements, and (3) a specialized measurement instrument equipped with an analog feedback unit for high-speed measurement, a fivefold increase in TEG evaluation speed was obtained. >

SAR image segmentation was attempted using the spatial association of elements based on pixel intensities. The associations (1) among very bright targets, (2) between very dark areas and the surrounding area, and (3) between the bright side and the dark side (ridge structures) were investigated. >

The delivery management method with marker lot and lot-sampling scheduling (LSS) has been developed. This method can reduce allocated memory compared to the conventional dynamic scheduling method. The reduction in allocated memory enables increasing the maximum number of lots to simulate the delivery date and to control turn-around-time (TAT). The accuracy of the simulated delivery date is within two days even for low-priority lots. Progress in processing is controlled by varying the resource allocation ratio for scheduling lots. This method is effective for delivery data control in manufacturing lines, including lots with various priority. >

A description of an automatic program generation system for plant controllers is presented. The proposed method makes it possible to generate the program by expressing the operation procedure document clearly using symbols, blocks with sentences, lines, and signal names and by relating them to program modules which are based on a hierarchical and standard structure. The operation procedure document is monitored in real time with the original document format on a CRT display. >

This paper discusses the effects of element length, installation of fins and exhaust gas flow rate on the power output and the conversion efficiency of a thermoelectric generation system using the exhaust gas of an internal combustion plant. The thermoelectric module consists of bismuth-tellurium based thermoelectric elements, electrodes, insulators, etc. A thermoelectric generation system consists of thermoelectric generation modules sandwiched by two square heat transfer tubes inside which exhaust gas and cooling water flow in a counter-current. It is supposed that the thermoelectric generation system recovers the heat of the exhaust gas of 60000 Nm/sup 3//h at 370/spl deg/C of an internal-combustion plant whose declared power is 10000 kW until it falls to 180/spl deg/C, and converts it into electricity. The power generation performance is obtained by the heat balance equations in the steady status between fluids and thermoelectric elements for each thermoelectric element inside the system and performing interactive calculations repeatedly. The power generation performance depends on the element length, the heat transfer area inside the hear transfer tube and the exhaust gas flow rate. As the difference between the temperature applied on the upper portion of the element and the temperature applied on the lower portion of the element becomes larger, the power generation performance is improved. The power output of 184 kW is recovered from the heat of exhaust gas of an internal-combustion plant whose declared output is 10000 kW when the element length is 15.2 mm, the fin efficiency is 4 and the exhaust gas flow rate per tube is 1212 Nm/sup 3//h.

Developing a new driving method for a brushless DC motor, the authors report a manner of motor operation by using a "vector chart" in this paper, and make the feedback operation clear in the method. As a result, the motor is driven at more than 16,000 RPM and starts quickly without any sensing elements in the motor, i.e. is a sensorless driving motor.

Peltier current lead was proposed to reduce heat leak from the current lead. The temperature of the hot side of semiconductors was kept to be a room temperature and the liquid nitrogen was used to cool the system in the experiment. The experiment confirmed the principle of the Peltier current lead, and the reduction of the heat leak is calculated to be 30% for the liquid helium system and 40% for the liquid nitrogen system. We also proposed a new current lead system which is composed of semiconductors and high temperature superconducting material (HTS). This idea bases on the functionally gradient material (FGM), and the HTS is connected to the semiconductor directly. The temperature of the hot side of semiconductor is kept to be the liquid nitrogen temperature, the temperature of HTS can be expected to be lower than 77 K. Therefore, we can expect high current capacity of the HTS and/or high stability of the HTS. We use BiSb as a N-type semiconductor and BiTe as a P-type semiconductor in the experiment, and the temperature of the cold side of the semiconductor is 73 K in this experiment.

The authors have compared NDVI and the feature mixing model as a practical semi-quantitative measure of daily vegetation. In the comparison, they used AVHRR data for a warm, humid and relatively flat eastern China. While NDVI only gives a general trend, the results obtained using the feature mixing model directly gives a more plausible picture of the vegetation of the corresponding terrain.

Location of road intersections were estimated automatically from ERS-1 single look SAR imagery using a Hough transform based approach. After applying a despeckle filtering which preserves small features in the SAR images, several practical methods to facilitate detection of peaks in a Hough space were developed.

A robust method to describe any shape which is observed in remote sensing images has been developed. In this method, an object is expanded in a series of pattern primitives or structural elements of different sizes. The first few expansion coefficients of a small number of different primitive expansion sets reasonably approximate the shape of an object in remotely sensed data in terms of shape differences. The method has been applied to a transformed JERS-1 SAR image.

A novel lensed fiber for high-efficiency coupling between an SMF and a high-power LD having a high aspect ratio of 42 was developed and fabricated for the first time. A coupling loss of 2.4 dB was obtained.

A method for detecting and visualizing narrow open-water rivers using very strong scatterers was applied to a series of JERS-1 SAR images of tropical forests in New Guinea. These images were observed in November and December, 1995 and February and March, 1996. The results indicate that the narrow river water levels on the Pacific side of the major mountain range stayed relatively constant during this period, while the water levels on the Australian side were low in November, highest during February and March and slightly lower in December.