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In this paper, we present a prototype transmitter and receiver with set partitioning (SP)-64 amplitude and phase shift keying (APSK) coded modulation we developed for expanding satellite transmission capacity. SP-multi-level coded modulation is a transmission scheme that can improve noise immunity by properly combining a modulation scheme, bit allocation, and error-correction codes. We designed SP-64APSK coded modulation on the basis of channel capacity for expanding satellite transmission capacity. We confirmed that it has higher robustness to additive white Gaussian noise (AWGN) than DVB-S2X’s 64APSK modulation with Gray mapping through computer simulation. We also developed a prototype transmitter and receiver to implement our SP-64APSK coded modulation and evaluated its transmission performances in an AWGN channel and in a non-linear channel simulating 12-GHz-band satellite transponder characteristics. We describe the method of designing our SP-64APSK coded modulation through computer simulation, the modulation/demodulation process, and transmission performances of the prototype transmitter and receiver. We also indicate that 8K ultra-high definition television (UHDTV) with an encoded bit rate of 150 Mbps can be transmitted using the prototype within 34.5 MHz, which is the bandwidth of a single transponder for satellite broadcasting in Japan. [ABSTRACT FROM AUTHOR]

Describes the above-named upcoming special issue or section. May include topics to be covered or calls for papers. [ABSTRACT FROM PUBLISHER]

Nine toroidal field (TF) coils have been developed in Japan for the international thermonuclear experimental reactor (ITER). The joint resistance of TF coil should satisfy the requirement of smaller than 3 nano-ohm at 2 T of external magnetic field and 68 kA of transport current. Full-size joint sample (FSJS) tests were performed for joint development and for TF coil manufacture, as part of the process control. 11 FSJS tests are conducted in total. FSJS tests were conducted with assistance from a test faculty in the National Institute for Fusion Science as reported in a previous paper. All FSJS tests successfully satisfied the requirement of resistance less than 3 nΩ at 2 T. Additionally, the TF coil joints are subjected to cyclic electromagnetic force and warm-up/cool-down during the ITER operation. The authors investigated the joint performance for the abovementioned influence. The results showed no degradation in the joint resistance. Thus, the TF joint developed in Japan was qualified successfully. [ABSTRACT FROM AUTHOR]

In recent years, there have been several reports of blade damage caused by lightning strikes on wind turbines. A few of these accidents have resulted in more serious secondary damage owing to the continued rotation of the damaged blades. To prevent the initial damage from spreading in this manner, wind farms in the regions of Japan vulnerable to winter lightning were required to introduce lightning detection systems, which can accurately detect when lightning strikes the wind turbine and then immediately stop the rotation of the blades. Normally, when the system detects a lightning strike to a wind turbine and stops operation, the process of restarting is initiated only after the soundness of the blades is confirmed by visual inspection. However, in bad weather, it is often difficult to check the soundness of the blade visually, and the resulting delay in the restart process prolongs the downtime and reduces the availability of the wind turbine. In this paper, we report the results of using the supervisory control and data acquisition (SCADA) system data to check the soundness of the blades after a lightning strike to resume operations more quickly, thereby increasing up-time. [ABSTRACT FROM AUTHOR]

The low-level RF (LLRF) control system for the rapid cycling synchrotron of the Japan Proton Accelerator Research Complex started its operation in 2007. The key functions of the LLRF control system are the dual-harmonic auto voltage control, which generates the superposed voltages of the fundamental accelerating harmonic and the second harmonic in a single wideband magnetic alloy (MA) cavity, and the multiharmonic RF feedforward to compensate the beam loading in the MA cavity caused by high-intensity beams. These functions are necessary to accelerate high-intensity proton beams. The system has been working well without major problems for more than ten years. However, the old field-programmable gate arrays (Xilinx Virtex-II pro and others) are discontinued and not supported by the current development environment. It will be difficult to maintain the system in a near future. Thus, we are planning to replace the existing Versa Module Europa (VME)-based LLRF control system with a new MicroTCA.4-based system. The system controls 12 cavities independently and calculates the vector sum of the cavity voltages in real time for phase feedback. Signal and data transfer between the modules is a key to realize the functions. In the existing system, the transfer is implemented not only using the backplane but also serial link via cables between the VME modules. It is much more simplified in the new system thanks to the high-speed communication capability of the MicroTCA.4 backplane. In this paper, we describe the configuration of the system under development, the implemented functions, and the preliminary test results. [ABSTRACT FROM AUTHOR]

An unusual negative lightning flash was recorded at the Säntis Tower on June 15, 2012. The flash did not contain an initial continuous current typical of upward negative lightning, which is the most common type of event at the Säntis Tower. The flash contained four strokes, the last three of which were normal while the current associated with the first stroke resembled a Gaussian pulse with an unusually high peak value of 102.3 kA, a long risetime of 28.4 μs, and a pulsewidth of 53.8 μs, which was followed by an opposite polarity overshoot with a peak value of 8.5 kA. Our current records suggest the involvement of a long upward connecting positive leader in response to the approaching downward negative leader in the formation of this flash. Lightning location system (LLS) data indicate that a positive cloud-to-ground stroke occurred 1 ms prior to the first stroke of the flash. In this paper, we present a detailed description of the data associated with this event. Moreover, both a return stroke model and an M-component model are used to reproduce the far-field waveform of this bipolar stroke. The simulations result in a radiated electric field waveform that is similar to those of large bipolar events (LBEs) observed in winter thunderstorms in Japan. A sensitivity analysis of the used simulation models reveals that, by proper selection of the input parameters, all field waveform characteristics, except for the positive half-cycle width, can be made to fall in the range of LBE field characteristics reported in Japan. [ABSTRACT FROM AUTHOR]

Direct observation of lightning current is a fundamental approach to evaluating lightning parameters, which are among the most basic factors for the lightning protection design of various grounded objects. However, for a tall grounded structure, upward lightning flashes initiated from the top of the structure have usually been observed, and the direct observation results of downward flashes have been limited. We developed and installed a pair of Rogowski coils at Tokyo Skytree, which is a 634-m-high freestanding broadcasting tower in Japan (35.71°N, 139.81°E), and have conducted direct observation of lightning flashes striking the tower. As of November 2018, 70 lightning flashes striking the tower, 26 downward and 44 upward, have been observed since the end of February 2012. In this paper, we focus on the downward negative flashes that occurred at the tower for seven years from 2012 to 2018 and report on the observed results of typical waveform parameters of lightning stroke currents in comparison with other observed results on downward negative flashes. [ABSTRACT FROM AUTHOR]

The determination of the accurate composition ratio of scattering mechanisms (volume scattering, double-bounce scattering, and surface scattering) within a radar backscatter is essential to validate current polarimetric decomposition techniques. Multiincidence angle and multipolarimetric synthetic aperture radar (MIMP SAR) observations at the X- and L-bands were applied to rice paddies at late vegetative stage in Niigata City in Japan in 2014 and 2016, respectively. In this paper, multifrequency MIMP SAR analysis is introduced based on the observation results. The approach, combined with theoretical characterization of the data by a discrete scatterer model, showed that rice panicles affect the backscatter from rice paddies. Contrary to expectation, an effect of transmissivity by using different bands is not obvious. The similar level of copolarization (HH and VV) backscatter at X- and L-bands could be explained by the effective size of rice panicles. They are the most characteristic scatters in rice paddy field with respect to multiple frequency polarimetric sensing. In addition, HV shows a distinct sensitivity to the mean orientation angle and the size of panicles regardless of the wavelength. The mean orientation angle affects the polarimetric randomness under azimuthal symmetry, whereas the size of panicles directly affects the attenuation of the volume scattering from the grains. The multifrequency MIMP SAR analysis also indicated the importance of considering the backscatter and attenuation in the interpretation of the backscattering cross section from vegetated fields. [ABSTRACT FROM AUTHOR]

The Japan Meteorological Agency (JMA) successfully launched the Himawari-8 (H-8) new-generation geostationary meteorological satellite with the Advanced Himawari Imager (AHI) sensor on October 7, 2014. The H-8/AHI level-2 (L2) operational cloud property products were released by the Japan Aerospace Exploration Agency during September 2016. The Voronoi light scattering model, which is a fractal ice particle habit, was utilized to develop the retrieval algorithm called “Comprehensive Analysis Program for Cloud Optical Measurement” (CAPCOM-INV)-ice for the AHI ice cloud product. In this paper, we describe the CAPCOM-INV-ice algorithm for ice cloud products from AHI data. To investigate its retrieval performance, retrieval results were compared with 2000 samples of the ice cloud optical thickness and effective particle radius values. Furthermore, AHI ice cloud products are evaluated by comparing them with the MODIS collection-6 (C6) products. As an experiment, cloud property retrievals from AHI measurements, with an observation interval time of 2.5 min and ground-based rainfall observation radar data (the latter of which is supplied by the JMA, with a 1-km grid mesh), are used to investigate the generation processes of deep convective (DC) cloud in the vicinity of the Kyushu island, Japan. It revealed that AHI measurements have the capability of monitoring the growth processes, including variation of the cloud properties and the precipitation in the DC cloud. [ABSTRACT FROM AUTHOR]

Recently, population aging and declining birth rate have become very serious, and people who lack walking capability have truly increased in Japan. To address this issue, gait training has become a requirement for them. Although some training systems have been researched in the past, a training system that entails guidance of walking has not been researched well. This paper focuses on guidance of walking, and it is aimed to develop a training system that utilizes the activity and passivity of the trainee. In addition, rhythmic walking, which takes walking stability and trainee safety into account, is aimed for. In this paper, an improved electric wheelchair is used as gait-training equipment (GTE); then, the trainee is towed by the GTE, and walking is guided. In this paper, a targeted walking cycle is predefined, and the GTE must distinguish the cycle in order to guide walking. Therefore, this paper uses the center of gravity (COG) of the trainee as the index. Thus, the GTE tows the trainee when the swing leg moves more forward than the stance leg; then, rhythmic walking can be guided. In addition, this paper proposes a method to control the GTE by a proportional-differential controller based on virtual compliance that is composed of mass, spring, and damper. The gait training can be safely achieved by deciding the desired position and velocity of the GTE from the tow force through virtual compliance. In this paper, the validity of the proposed method is verified by numerical simulation and experiment. The validity of the proposed system is verified by using a four-link robot whose geometric expression is known as the trainee; then, the application of the proposed method will be extended to a human trainee by only adjusting the parameters. [ABSTRACT FROM AUTHOR]

Abstract-This paper investigates the correlation between max- imum temperature increases and peak spatial-average specific ab- sorption rates (SARs), calculated by different average schemes and masses. For evaluating the effect of mass on the correlation prop- erly, a three-dimensional Green's function is presented. From our computational investigation, no best average mass for peak spatial- average SAR exist from the aspect of the correlation with maximum temperature increase. This is attributed to the frequency dependent penetration depth of EM waves. Maximum temperature increase in the head including the pinna is reasonably correlated with peak spatial-average SARs for most average schemes and masses consid- ered in this paper. Maximum temperature increase in the head only (excluding the pinna) is reasonably correlated with peak 1O-g SARs for the average schemes considered in this paper. The rationale for this result is explained using the Green's function. The point to be stressed here is that the slope correlating them is largely dependent on the average scheme and mass. Additionally, good agreement is observed in the slopes obtained by using two head models, which have been developed at Osaka University and Nagoya Institute of Technology. However, weak correlation is observed for the brain, which is caused by the difference of the positions where peak SAR and maximum temperature increase appear. The 95th percentile values of the slope correlating maximum temperature increases in the head or brain and peak spatial-average SAR are quantified for different average schemes and masses. [ABSTRACT FROM AUTHOR]

This paper intends to provide general information about the experiences of numerical relay operation under many different kinds of surges from switchyards in Japan. The main focus of this paper is to investigate the immunity of numerical relays against a switching surge with relatively high frequency in a gas-insulated substation that is considered to be severe for the relay's correct operation. It is concluded that the reliability of today's numerical relays in Japan against the switching surge is almost sufficient due to the effectiveness of the immunity test standard adopted and countermeasures against the switching surge in Japan. [ABSTRACT FROM AUTHOR]

This paper reviews the operational phase of the negative-ion-based neutral beam systems on the JT-60U tokamak in Naka, Japan and the large helical device (LHD) stellarator in Toki, Japan. These systems were the first high power negative ion beam systems to be deployed for any application, and thus represented large advances in the state of the art for negative ion sources and accelerators, especially since the ions used were hydrogen and deuterium, which have only a modest electron affinity. This paper re- views the systems, the principal problems encountered, and the improvements they engendered, as well as the progress of these systems to the present time. The role of neutral beams in fusion is also discussed, and some of the contributions of the negative ion systems to the physics programs of JT-60U and LHD are briefly reviewed. These systems have been central to the success of JT-60U and LHD, and the knowledge gained about their characteristics should provide a strong basis for the development of the next generation of negative-ion-based neutral beams for ITER and other large fusion devices. [ABSTRACT FROM AUTHOR]

Fatal accidents caused by electric shock have been occurring since electricity was first introduced. Overall, the number of fatal accidents is decreasing. However, the decrease in the number of fatalities has slowed in recent years. A statistical study is needed to reconsider the preventive measures against these accidents. In this paper, the trend of fatalities by accident type and industry in Japan is studied statistically. These results show that the electric fatality rates differ by industry. The fatalities in the construction and the electrical-construction industries make up approximately 60% of the total fatalities. In addition, the accident type is most frequently contact with electrical lines by either the human body or a tool. In these industries, the elimination of fatal accidents from shocks is an important subject. These results will be helpful in preventing fatal accidents by electric shock. [ABSTRACT FROM PUBLISHER]

This paper describes the results of neutron spectrometry and dose measurements using a Bonner Sphere Spectrometer (BSS) at the ring cyclotron facility of the Research Center for Nuclear Physics (RCNP), Osaka University, Japan. Quasi-monoenergetic neutron fields were generated using the ^7Li (p,n)^7~\!\!Be reaction and 246 and 389 MeV protons. Neutrons produced at 0^\circ and 30^\circ emission angles were extracted into a time-of-flight (TOF) tunnel, and the energy spectra were measured at a distance of 35 m from the target. To deduce the corresponding neutron spectra from thermal to the nominal maximum energy, the BSS data were unfolded using the MSANDB code and response functions were calculated by Monte Carlo (MC) methods. These spectra are compared to spectral measurements using NE213 organic liquid scintillators applying the TOF method. The results are discussed in terms of ambient dose equivalent H^\ast (10) and compared with the readings of other instruments operated during the experiment [ABSTRACT FROM PUBLISHER]

JAEA has conducted qualification and rationalization activities in Japan since March 2009 in order to rationalize manufacturing procedure of ITER toroidal field coil (TFC) structures. These following activities has been performed: qualification of structural materials and qualification and development of welding procedure according to the JSME code constituted for fusion devices, demonstration of the manufacturing method and procedures through manufacture of 1 m mock-ups and full-scale segments of TFC structure. From results of these activities, JAEA confirmed quality of materials and weld joints of gas tungsten arc welding and gas metal arc welding. In addition, JAEA obtained knowledge of welding deformation of actual TFC structures. This paper describes results of these qualification and development activities for ITER TFC structure. [ABSTRACT FROM PUBLISHER]

This paper describes the detailed design of the quench protection circuits (QPCs) for the superconducting toroidal field (TF) and poloidal field (PF) magnets of the satellite tokamak JT-60SA, which will be installed in Naka, Japan. The nominal currents to be interrupted and the maximum reapplied voltages are 25.7 kA and 2.8 kV for the TF QPCs and 20 kA and 5 kV for the PF QPCs. The innovative solution proposed in the QPC design is based on a hybrid circuit breaker (CB) composed of a mechanical bypass switch for conducting the continuous current, in parallel to a static CB for current interruption. The main choices of the final design are presented and discussed, either to confirm or to update and complete the study performed at the conceptual design level. [ABSTRACT FROM PUBLISHER]

Visual quality of compressed video sequences depends on factors including spatial texture content and cognition-based factors such as prior knowledge and task in hand. The MOSp metric is a full reference objective quality metric which predicts perceived quality of sequences with video compression-induced impairments based on the spatial texture content and the mean squared error between original and compressed video sequences. In this paper, we extend the MOSp metric to incorporate cognition-based factors to identify regions in a video scene that attract human attention. The proposed metric has been tested on a variety of multimedia sequences of common intermediate format resolution compressed at a wide range of bitrates using the H.264/AVC coding standard. This metric shows a higher correlation with mean opinion score (MOS) than popular metrics, such as peak signal-to noise ratio, National Telecommunications and Information Administration/Institute for Telecommunication Sciences video quality metric, PSNRplus, and the Yonsei University metric. Results also show that by extending the MOSp metric to incorporate cognition-based factors such as skin information, its correlation with subjective scores (MOS) can be significantly improved in video content where humans are present. This algorithm is particularly useful for real-time quality estimation of multimedia sequences with block-based video compression-induced impairments because all the parameters of the metric can be calculated automatically with a modest amount of processing overhead. [ABSTRACT FROM PUBLISHER]

The matrix inversion method (MIM) is an effective algorithm for estimating water constituent concentrations in case II waters. To apply this method, appropriate and accurate specific inherent optical properties (SIOPs) for each constituent in water are essential. However, many routine observations of lake water quality do not in fact provide SIOPs, thus limiting the application of the MIM. In this paper, an alternative MIM method based on linear matrix inversion theory was proposed to relax the requirement of SIOPs measurement. For this, so-called ESIOPs (Estimated SIOPs) were first derived by an unusual application of MIM based on adequate calibration samples; then the water constituent concentrations for the whole study area were retrieved by the standard application of MIM based on the derived ESIOPs. For each calibration sample, measurement of the reflectance spectrum and corresponding water constituent concentrations, which can be obtained from periodical satellite data and routine field surveys, is required. The performance of the proposed method was evaluated using the simulation data from Hydrolight and three MEdium Resolution Imaging Spectrometer Instrument (MERIS) images. The results showed that this method yielded satisfactory estimations of the water constituent concentrations for the noise-contaminated simulation data sets. For MERIS data in our study area (Lake Kasumigaura, Japan), the average bias (mean normalized bias or MNB) and relative random uncertainty (normalized root mean square error, or NRMS) were in the range of -11.2% to 3.4% and 4.8% to 29.7% for each water constituent concentration. These findings imply that the algorithm proposed in this study is theoretically reasonable and practically applicable. [ABSTRACT FROM AUTHOR]

In this paper, game models for risk information disclosure—which interpret user payoff structures according to March and Simon's theory of satisficing decision making and interpret a carmaker's payoff structures according to Tversky and Kahneman's cumulative prospect theory—are developed. This risk information disclosure game is used to analyze the recall of products by a carmaker. The transitions made from one game to another correspond to the carmaker's subjective risk assessment of the probability that nondisclosure will be discovered by the user. The user's claims hasten the carmaker's change from a nondisclosure game to another kind of game. The role of a guardian agent in fault information disclosure is examined. The presence of an agent caused the carmaker playing the game to change from nondisclosure to disclosure mode. From the viewpoint of operational cost, the risk information disclosure in an environment where a permanent guardian agent is always active is considered to be effective in achieving good risk communications. [ABSTRACT FROM AUTHOR]

HTS cable demonstration project supported by Ministry of Economy, Trade and Industry (METI) and New Energy and Industrial Technology Development Organization (NEDO) has started in Japan. The target of this project is to operate a 66 kV, 200 MVA HTS cable in the live network of Tokyo Electric Power Company in order to demonstrate its reliability and stable operation. The design of the HTS cable with DI-BSCCO has been completed as well as those of a termination and a joint. A 30-meter HTS cable system with terminations, a joint and a cooling system was installed in SEI facility to confirm their design and performance. Various tests as voltage tests, nominal and over current tests, heat cycle tests, heat loss measurements and so on were conducted and it is verified that the cable has good performances as design. This paper describes the design and test results of a 30-meter HTS cable, and discusses required test items of HTS cables. [ABSTRACT FROM AUTHOR]

For the design of an Interior Permanent Magnet (IPM) motor with small torque ripple and large driving torque, the optimal design method called the ON/OFF method is attractive, because a new magnetic circuit, which we could not imagined beforehand, may be obtained. In this paper, a non-parametric optimization technique to find a new magnetic circuit which minimizes a torque ripple and maximizes a driving torque of IPM motor is examined. The effectiveness of the ON/OFF method for the optimal design of a motor is examined by applying it to the design of the verification model of the IPM motor established by the technical committee of IEE of Japan. Factors affecting torque ripple and driving torque of the obtained optimal motor core are also discussed. [ABSTRACT FROM PUBLISHER]

This paper presents a field measurement of a simple antenna system mounted on a vehicle by utilizing a geostationary test satellite called Engineering Test Satellite VIII (ETS-VIII). Our developed antenna system is compact, lightweight, and promising for low-cost production. The antenna system is constructed by a 16-cm patch array antenna, which has simple satellite tracking that is controlled by a control unit as the vehicle's bearing is updated from a navigation system in real time. A Global Positioning System (GPS) module is utilized for the navigation system to provide accurate information of the vehicle's position and bearing during traveling. A control unit is provided as antenna-beam control and measured-data acquisition. We thoroughly examine the developed system in field measurements under open field areas and blockage areas in order to evaluate the propagation characteristics caused by utility poles, pedestrian overpasses, and vegetation-covered roads. In this measurement, the received signal power and the average bit error rate (BER) are simultaneously retrieved. Steadily received levels and average BER are satisfactorily attained during satellite tracking in open field areas. Moreover, the fade characteristics and average BER performance are also investigated during signal blockage. The results show that different environments give different degrees of attenuation, which affects the BER performance in terms of fade depth. Ultimately, our proposed antenna system can contribute to the design of future cost-effective mobile satellite communications. [ABSTRACT FROM PUBLISHER]

In this paper, a RF front-end of the 5.8 GHz integrated CMOS dedicated short range communication (DSRC) transceiver for the Korea/Japan electronic toll collection system is presented. The receiver uses low-IF conversion architecture for high sensitivity and low-power consumption while the transmitter uses direct up-conversion architecture for its simple structure and reliability. To solve image problem in the low-IF receiver, 10 MHz IF and 40 MHz IF are chosen for Korean and Japanese DSRC standards, respectively, since they make no image signals exist in image band. A single-quadrature mixer with the proposed transconductor-type quadrature generator in RF signal path is also adopted which has accurate quadrature characteristic in 5.8 GHz frequency. [ABSTRACT FROM PUBLISHER]

We developed a parallel computing method of the magnetic field for rotating machines by using the 3-D finite element method (FEM) with edge elements. In this paper, we describe the outline of the developed method and an optimization of the method for the Earth simulator, which is a vector-type parallel supercomputer in Japan. Moreover, the performance of the proposed method running on the Earth simulator is quantitatively clarified. [ABSTRACT FROM AUTHOR]

The mission of the JT-60SA Tokamak, which will be built in Japan, is to contribute to the early realization of fusion energy in support and supplement of the ITER program. The JT-60SA project is part of the broader approach for fusion energy. In 2008, due to a design change of the TF cross section, and following the redefinition of the global JT-60SA features, mechanical analyses were redone. The first 2D and 3D mechanical analyses were performed on the current TF design, providing useful information on the pros and cons of the new design. For the 2D analysis, the critical area of the inner leg cross section in the location of the equatorial plane was meshed to study the effect of in plane loads. The analysis includes checking the peak field applied to the conductors and the stress on each of the components of the winding pack cross section, in particular in the insulation which is a critical component. The stress in winding pack cross section is due to the accumulation of cool down strain, "in plane" Lorentz forces and to the quench pressure. Both magnetic and mechanical analyses are performed with the ANSYS V11.0 code. In this paper, we present the main steps of the 2D and 3D FEM calculations which were developed by CEA and used in the following analyses. Associated statements concerning possible TF design optimization with respect to cost, feasibility or risk are also presented. [ABSTRACT FROM AUTHOR]

As an intense neutron source for the boron neutron capture therapy system, a FFAG storage ring with Energy/emittance Recovery Internal Target (ERIT) has been developed in the Kyoto University Research Reactor Institute (KURRI). In order to develop storage ring for ERIT scheme, the spiral sector and radial sector FFAG rings were designed and compared about performance in ERIT system. The 3-dimensional magnetic fields of these magnets were calculated with the field analysis code, TOSCA. The pole shape of magnet was carefully optimized checking the betatron tune. Tunes were computed by means of tracking simulations in field maps based on TOSCA models. In this paper, the FFAG magnet design for ERIT system and the construction of FFAG ring in KURRI are described. [ABSTRACT FROM AUTHOR]

We analyse the issues of quench propagation in the NbTi Poloidal Field Conductor Insert (PFCI), recently tested at JAEA Naka, Japan. The simulation tools Mithrandir, already validated against data from previous Nb3Sn Insert Coils, and M3, implementing a more detailed thermal-hydraulic description of the CICC cross section, are used. The results of the analysis are reported in the paper and compared with experimental data, with particular attention to NbTi versus Nb3Sn features and to the effects of different model assumptions. [ABSTRACT FROM AUTHOR]

The peak current amplitude and front duration of lightning stroke current waveforms have conventionally been evaluated independently, and severe waveform assumptions are usually adopted in the current of lightning insulation designs. If lightning stroke waveform conditions are optimized, lightning insulation specifications of power facilities can be further rationalized. This paper proposes a new statistical technique to better evaluate lightning stroke current waveforms. The characteristics of lightning stroke current waveforms (i.e., that peak amplitudes correlate with front durations) are taken into account in this technique. The proposed technique was validated with various statistical tests. The front duration currently used in the design of the ultra-high-voltage system in Japan is 1.0 μs, but the potentially more accurate value of 1.7 μs was found when waveforms were evaluated with the proposed technique, and overvoltage analyses of gas-insulated switchgear show that overvoltages decrease with longer front duration. [ABSTRACT FROM AUTHOR]

In this paper, lightning electric field waveforms related to notable power transmission-line faults in winter along the coastline of the Sea of Japan were examined. Most of the wave- forms of the observed electromagnetic field changes, which were more than five times as intense as an average negative return- stroke fields, are inferred to be associated with upward lightning discharges. Lightning discharges that produce such characteristic waveforms are termed ground-to-cloud flashes, and properties of the associated electric field waveforms are examined. These lightning discharges in winter distribute around the coastline of the Sea of Japan in different ways depending on their polarities. [ABSTRACT FROM AUTHOR]

ITER PFCI has been manufactured in the Europe and installed into the ITER Test Facility in Naka, Japan. The conductor is NbTi cable-in-conduit conductor with thick square stainless steel jacket and almost identical with the design of the ITER PF coils. The main objective of this test is the characterization of the conductor and joints at the conditions relevant to the ITER PF coil operation. Intermediate joint is located in the winding at relatively high field to examine its performance. The main items in the PFCI test program are thermo-hydraulic test, DC mode test, cyclic test and pulse mode test. The PFCI and CSMC were successfully cooled down to cryogenic temperature within 450 hours. The test of the PFCI was performed from May to August 2008. The key technology of the installation, the test methods and procedures, and some preliminary results of cool-down are described in this paper. [ABSTRACT FROM AUTHOR]

This paper summarizes the calibration of precision coaxial air lines in a 3.5-mm line size. The standard system of the National Metrology Institute of Japan (NMU) is used to accurately obtain mechanical measurements of the diameters and lengths of lines. Length compression of approximately 6.0 μm and diameter distortions caused by connections with specified torques have been observed in 3.5-mm air lines. A small insertion loss in the millimeter-wave frequency range has also been detected. Furthermore, NMIJ has established standards for scattering parameters in the frequency range up to 110 GHz for coaxial air lines in the 1.0-mm line size by the enhancement of mechanical measurement systems. [ABSTRACT FROM AUTHOR]

This paper addresses a robust decentralized proportional-integral (P1) control design for power system load- frequency regulation with communication delays. In the proposed methodology, the P1-based load-frequency control (LFC) problem is reduced to a static output feedback control synthesis for a multiple-delay system. The proposed control method gives a suboptimal solution using a developed iterative linear matrix inequalities algorithm via the mixed H2 /H∞ control technique. The control strategy is suitable for LFC applications that usually employ the PI control. To demonstrate the efficiency of the proposed control strategy, an experimental study has been performed at the Research Laboratory, Kyushu Electric Power Company, Japan. [ABSTRACT FROM AUTHOR]

A new ac-dc comparator system of 20-1000 V has been developed at the National Metrology Institute of Japan (NMLJ) for the calibration of ac-dc thermal voltage converters (TVCs), which are used as national ac-dc transfer standards. The ac-dc transfer differences of high-voltage transfer standards were evaluated by a traditional step-up procedure. The voltage dependence of the ac-dc transfer difference was observed in the earlier step-up procedures over 300 V, as reported by the latest international intercomparison. The experimental results for high- voltage TVCs with several different range resistors at the NMU suggest that the voltage dependence may primarily be caused by input connectors of range resistors and the change in the resistance value of the resistor and TVC modules due to heating from resistors. This paper describes the voltage dependence improvement of ac-dc transfer differences over 300 V at the NMLJ. [ABSTRACT FROM AUTHOR]

This paper examines strategic capabilities as drivers of the development and launch of radical innovations. We construct a theoretical framework relating five strategic capabilities (mar- keting, market linking, technology, information technology, and management-related capabilities) to radical innovation. From this framework, we derive hypotheses concerning a division's propensity to engage in radical innovation. Using empirical data derived from a research study of 376 firms in the United States, Japan, and China, we apply analysis of variance and negative binomial distribution (NBD) regression techniques to test our hypotheses. We find evidence that, overall, technology and information technology capabilities are significantly and positively related to radical product innovation. We also find some significant differences among the three country samples concerning drivers of radical innovation. Marketing capability is more significantly and positively related to radical innovation in the United States than in Japan; and, in China, the only capability that is significantly and positively related to radical innovation is technology. All of the findings completely or partially support our research hypotheses. We conclude with a discussion of the managerial implications of our findings, and directions for future research. [ABSTRACT FROM AUTHOR]

The Broader Approach agreement between Europe and Japan includes the construction of a fully superconducting tokamak, the JT-60 Super Advanced (JT-60SA), as a satellite experiment to ITER. In particular, the whole Toroidal Field magnet system, described in this paper, will be provided to Japan by the EU. All the TF coil main constituents, i.e. conductor, winding pack, joints, casing, current leads, are here presented and discussed as well as the design criteria adopted to fulfil the machine requirements. The results of the analyses performed by the EU and JA to define and assess the TF magnet system conceptual design are reported and commented. Future work plan is also discussed. [ABSTRACT FROM AUTHOR]

The upgrade of JT-60U to JT-60 Super Advanced (JT-60SA), a fully superconducting tokamak, will be performed in the framework of the Broader Approach (BA) agreement between Europe (EU) and Japan. In particular, the Toroidal Field (TF) system, which includes 18 coils, is foreseen to be procured by France, Italy and Germany. This work covers activities from design and manufacturing to shipping to Japan. The present paper is mainly devoted to the analyses that lead to the conductor design and to the technical specifications of the joints for the JT-60SA TF coils. The conductor geometry is described, which is derived from Cable-In-Conduit concept and adapted to the actual JT-60SA tokamak operating conditions, principally the ITER-like scenario. The reported simulations and calculations are particularly dealing with the stability analysis and the power deposition during normal and off-normal conditions (AC losses, nuclear heating). The final conductor solution was selected through a trade-off between scientific approach and industrial technical orientation. Besides, the TF system connections layout is shown, derived from the industrially assessed twin-box concept, together with the associated thermo-hydraulic calculations ensuring a proper temperature margin. [ABSTRACT FROM AUTHOR]

In our previous regression model for estimating forest biomass, it was shown that non-Gaussian amplitude fluctuations in high-resolution polarimetric synthetic aperture radar (SAR) data of coniferous forests can accurately be described by the K-distribution and that the order parameter of the K-distribution can be useful in estimating the tree biomass of coniferous forests from L-band cross-polarization amplitude images in a wider range than the conventional method using the radar cross section alone. The result was based on the analysis of the "ground-truth" biomass data of 19 forest stands and airborne polarimetric interferometric SAR L-band data over the Tomakomai forests in Hokkaido, Japan. From this relation, an empirical regression model was developed to estimate forest biomass from SAR data. In this paper, we report the results on further analyses of this regression model. The validity of the K-distribution is first reconfirmed using the Akaike information criterion, followed by the description on the accuracy of the model. To examine model accuracy, we carried out further field measurements on 22 forest stands in 2005, and the ground survey was made in 2006 to find out the causes of several anomalous data. Based on a comparison of the model-based biomass and the ground-truth data, the accuracy of the model was found to be approximately 86%. The regression model was then updated for practical application in estimating the biomass of the Hokkaido forests by including the ground-truth data of all 41 forest stands. [ABSTRACT FROM AUTHOR]

Aged fossil-fired power plants are on the great increase in Japan, and the importance of preventive maintenance (PM) increases for their steady operations. A plant consists of a wide variety of mechanical and electrical components. Various kinds of severe failures inherent in these components and their occurrence probabilities are different. A system fails when the total suffered damage exceeds a peculiar level, i.e., these components have their peculiar damage levels. The PM plan should be established, considering such levels of plant components. In this paper, N kinds of peculiar cumulative damage levels Ki (i = 1,… , N) are considered, and a system fails when the total damage exceeds these damage levels. The PM is performed when the total damage exceeds the managerial one k(< Ki). The expected cost per unit time between maintenances is secured, and the optimal managerial level k* which minimizes it is analytically discussed. [ABSTRACT FROM AUTHOR]

Reconstruction of 3-D objects from multiaspect high-resolution synthetic aperture radar (SAR) images is of great importance for SAR technology applications. In this paper, simple building objects are modeled as cuboids, and an approach for automatic reconstruction of 3-D building objects from multiaspect SAR images in meter resolution is developed. The edge detector of constant false alarm rate and a Hough transform technique for parallel line segment pairs are first employed to extract the parallelogram-like image of the building walls in SAR images. A set of probability density functions is presented to describe the object images and their multiaspect coherence. The maximum-likelihood estimation of an object is then derived from its multiaspect object images. A hybrid priority criterion is defined to evaluate the reliability of the reconstruction result. An automatic reconstruction algorithm is further developed to match object images of different aspects and, finally, to reconstruct the building objects. Besides, an iterative method is proposed for the coregistration of multiaspect building images. Four-aspect simulated images of a virtual scene and four-aspect Pi-SAR images over the campus of Tohoku University, Japan, are investigated. Reconstruction of building objects from their multiaspect images shows the fidelity of the whole process chain and the feasibility of 3-D objects automatic reconstruction from multiaspect SAR images. At last, a practical application that is based on spaceborne meter-resolution SAR is proposed. [ABSTRACT FROM AUTHOR]

This paper documents the production and validation of retrieved rainfall data obtained from satellite-borne microwave radiometers by the Global Satellite Mapping of Precipitation (GSMaP) Project. Using various attributes of precipitation derived from Tropical Rainfall Measuring Mission (TRMM) satellite data, the GSMaP has implemented hydrometeor profiles derived from Precipitation Radar (PR), statistical rain/no-rain classification, and scattering algorithms using polarization-corrected temperatures (PCTs) at 85.5 and 37 GHz. Combined scattering-based surface rainfalls are computed depending on rainfall intensities. PCT85 is not used for stronger rainfalls, because strong depressions of PCT85 are related to tall precipitation-top heights. Therefore, for stronger rainfalls, PCT37 is used, with PCT85 used for weaker rainfalls. With the suspiciously strong rainfalls retrieved from PCT85 deleted, the combined rainfalls correspond well to the PR rain rates over land. The GSMaP algorithm for the TRMM Microwave tmager (TMI) is validated using the TRMM PR, ground radar [Kwajalein (KWAJ) radar and COBRA], and Radar Automated Meteorological Data Acquisition System (AMeDAS) precipitation analysis (RA). Monthly surface rainfalls retrieved from six microwave radiometers (GSMaP̱MWR) are compared with the gauge-based dataset. Rain rates retrieved from the TMI (GSMaP̱TMI) are in better agreement with the PR estimates over land everywhere except over tropical Africa in the boreal summer. Validation results of the KWAJ radar and COBRA show a good linear relationship for instantaneous rainfall rates, while validation around Japan using the RA shows a good relationship in the warm season. Poor results, connected to weak- precipitation cases, are found in the cold season around Japan. [ABSTRACT FROM AUTHOR]

Since 2003, three years of the current 5-year national project for development of coated conductors using Y-system superconductors have passed and remarkable results have been achieved. In this paper, the current status and future prospects are reviewed. The group of Fujikura and SRL has worked on a long tape with high performance in the PLD-YBCO supercon- ducting tapes on the IBAD-GZO buffered substrates. The highest Ic × L value of the tape is over 50 k Am which is 212 m in length and 245 A of critical current (Ic). Additionally, a 500 m long IBAD-buffered tape with a reasonable in-plane texture was produced using a large scale IBAD apparatus by Fujikura. In the other group, long tape processing has been developed focusing on lowering production cost. An extremely high Ic value of 692 A was obtained in a short sample by the advanced TFA-MOD method on a CeO2 (PLD)/GZO(IBAD)/Hastelloy substrate. In the efforts for the long tape processing, a 25 m long tape with the Ic value of 100 A by a continuous reel-to-reel system and a 40 m long tape with 155 A by a batch system were realized. 100 m class long tapes were also obtained with the MOCVD and PLD-HoBCO processes. Both groups are aiming for 500 m long tapes with the high Ic value of 300 A/cm-w with a production rate of 5 m/h. Furthermore, feasibility studies for applications using coated conductors have already began due to the above mentioned success of long tape production. Several kinds of coils using the long coated conductors such as solenoid and pancake types and spiral shaped conductors for the cable were made. Reasonable high performance results were confirmed in the trials. New approaches on the preliminary studies for the applications of cables, transformers, motors and current limiters etc. are planned in this project. [ABSTRACT FROM AUTHOR]

Development of the SMES using high temperature superconducting (HTS) coil has progressed as a Japanese national project since FY 2004. The objective of the project is to obtain around twice the normal energy density via an HTS-LTS ‘hybrid’ coil system compared to an LTS coil system. The HTS coil is composed of sixteen double-pancake coils and the double-pancake coil is wound with a Bi2212 Rutherford-type cable. The HTS coil is operated at 4.2 K in liquid helium bath with the LTS coil, and operated at maximum field of 8.9 T. Before we made a hybrid coil system, we verified the design issues using HTS experimental coils. In this paper mechanical compression tests, DC operation tests and thermal runaway tests using the experimental coils are discussed. [ABSTRACT FROM AUTHOR]

To clarify the relationship between earthquakes and electrical phenomena, signals of three parameters were observed continuously at Sennan in Akita Prefecture, Japan: ground acceleration (GAC), earth potential difference (EPD), and electrostatic field in the atmosphere (EFA). A large metal plate was used as an electrostatic antenna to observe EFA variation. For this paper, we used the digital natural observation (D-NOB) method as a signal processing technique and found clear EPD and EFA waveforms during seismic wave propagation. Our observation and examination results show that GAC causes EPD variation. Subsequently, the EPD variation induces EFA variation. [ABSTRACT FROM AUTHOR]

This paper describes the development of the AntConc corpus analysis toolkit, originally designed for use in a technical writing course at Osaka University, Japan, but now adopted in institutions throughout the world as an easy-to-use, freeware, multiplatform alternative to the many commercial concordance programs. First, I will explain how the software was originally tailored to the needs of students in the Osaka writing course and later to a general audience through the requests and feedback from teachers and students around the world. Then, I will give an overview of tools in the most recent version of AntConc and explain their value using examples from the classroom. Finally, I will discuss some of the software's limitations and future developments, and suggest applications in professional communication. [ABSTRACT FROM AUTHOR]

To evaluate the characteristics of commercial memory devices for space use, the Japan Aerospace Exploration Agency (JAXA) launched a Solid State Recorder (SSR) on the Mission Demonstration test Satellite-1 (MDS-1 or ‘Tsubasa’) into geo-stationary transfer orbit (GTO) in February 2002. Passing through the radiation belt exposed the MDS-1 to severe radiation environment in every orbit. This flight experiment allowed the observation of Single-Event Upsets (SEU) and Total Ionizing Dose (TID) effect on a large number of stacked 64 Mbit Dynamic Random Access Memories (DRAM). As a result, the actual SEU rates could be calculated, and the capabilities of two types of on-the-fly Error Detection and Correction (EDAC) mechanisms were confirmed. This paper presents the results of the space experiment of SSR, focusing especially on SEU analysis. [ABSTRACT FROM AUTHOR]

A high-temperature superconducting dipole floating in the magnetic field of a normal conducting coil has been developed for the Ring Trap (RT)-1 plasma confinement apparatus at the University of Tokyo. The RT-1 device consists of the floating superconducting dipole, a levitation coil made of normal conductor, a vacuum vessel for plasma confinement and detachable services for the floating dipole. This paper describes the design concept and operating scenario of the floating dipole as well as the required services such as a HTS persistent current switch necessary to realize this scenario. [ABSTRACT FROM AUTHOR]

This paper investigates the correlation between the peak specific absorption rate (SAR) and the maximum temperature increase in head models of adults and children due to a dipole antenna. Much attention is paid to the effect of variation of electrical and thermal constants on the correlation for the child models, since these constants of child tissues are different from those of adult tissues. For investigating these correlations thoroughly, a total of 1400 situations are considered for the following six models: 3-year-old child, 7-year-old child, and adult models developed at the Nagoya Institute of Technology and the Osaka the University. The numerical results are analyzed on the basis of statistics. We find that the maximum temperature increases in the head can be estimated linearly in terms of peak SAR averaged over 1- or 10-g of tissue. In particular, no clear difference is observed between the adult and child models in terms of the slopes correlating the maxi- mum temperature increase with the peak SAR. Also, the effect of electrical and thermal constants of tissue on these correlation is found to be marginal. Further, we discuss possible maximum temperature increases in the head and brain for SAR limits prescribed in safety guidelines. For the adult model developed at the Osaka Univ., these are found to be 0.26°C and 0.10°C at the SAR value of 1.6 W/kg for 1-g cubic tissue and 0.59°C and 0.21 °C at the SAR value of 2.0 W/kg for 10-g cubic tissue. Similarly, for the 3-year-old child model at Osaka Univ., these are 0.23°C and 0.11 °C for the value of 1-g SAR and 0.53°C and 0.20°C for the value of 10-g SAR. [ABSTRACT FROM AUTHOR]

Vacuum circuit breakers (VCBs) have been developed and widely applied in Japan to meet the requirements of increasing energy consumption and also in national security of various areas. As a result, for example, a 168 kV two break porcelain type and a 100 kA one break VCB have already appeared in the Japanese market and they are currently being exported to world-wide markets. VCBs interrupt currents in vacuum, and this means they do not exhaust dissolved gases which are sometimes harmful to the human body or cause effects on the environment. Therefore, by its nature, the recycling of materials and safety to the human body have been realized, and also no global warming effects would be expected. Energy is extremely essential and important in human daily life, and many types of circuit breakers play important roles in electrical power transmission and distribution systems to maintain the systems reliability and safety by switching the systems under several conditions. Since vacuum circuit breakers possess a lot of advantages such as high current interrupting capabilities, small size, and Low cost, they will be used much more in the future, and at this moment, we believe it is very worthy to discuss and consider thoroughly future trends of VCBs. In this paper, the results of the developments in Japan will be reviewed, the reflection of the results will be stated, and the subjects of engineering in the 21st century will be discussed. These will include recycling, safeguards to the human body and the fireless nature of VCBs; and it will be demonstrated that the developmental works of VCBs are being wonderfully explored in Japan now and in the future. [ABSTRACT FROM AUTHOR]

The Japan Aerospace Exploration Agency will launch the Engineering Test Satellite VIII (ETS-VIII) in 2006 to support the next generation of mobile satellite communications covering the area of Japan (beam coverage El = 38° to 58°). In this paper, a satellite-tracking left-handed circularly polarized triangular-patch array antenna is developed for ground applications. The targeted minimum gain of the antenna is set to 5 dBic at the central elevation angle (El = 48°), in the Tokyo area, for applications using data transfer of around a hundred kbps. The antenna is composed of three equilateral triangular patches for both reception and transmission units operating at 2.50 and 2.65 GHz frequency bands, respectively. The antenna was simulated by method of moments (MoM) analysis, and measurement of the fabricated antenna was performed to confirm the simulation results. The measurement results show that the frequency characteristics and the 5-dBic gain coverage in the conical-cut plane of the fabricated antenna satisfy the specifications for ETS-VIII. A prototype of the proposed antenna system is employed in outdoor experiments using a pseudosatellite and shows good performance from El = 38° to 58°. [ABSTRACT FROM AUTHOR]