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

Since its beginning in 1992 in Japan, International Symposium on Semiconductor Manufacturing (ISSM) has provided unique opportunities to share the best practices of semiconductor manufacturing technologies for professionals. At the symposiums, semiconductor manufacturing professionals discussed the technologies developed to meet the worldwide requirements for advanced manufacturing. It is becoming crucial to re-examine semiconductor manufacturing in terms of fundamental principles to improve the performance of semiconductor devices. Moreover, utilizing artificial intelligence and machine learning technologies to improve semiconductor manufacturing have become a new challenge. These manufacturing technology challenges are showing the need for drastic revolutionary concept and stronger collaborative efforts to find solutions to the precompetitive challenges. [ABSTRACT FROM AUTHOR]

This paper proposes an algorithm for disaster avoidance control against heavy rainfall. According to weather information, the algorithm reconfigures a logical network (slice), including the migration of virtual machines (VMs), to avoid disasters. It was applied to a nationwide network of 105 nodes and 140 edges, including cases with more than 10 000 slices. Through numerical simulations using actual data of rainfall that caused significant damage in Japan, we found that the probability of service disruption under the proposed control with suitable parameter settings is 10%–30% of that without control, on average. Our proposed control experimental system is implemented by using the software-defined network technology. It can migrate VMs and estimates VM migration time to determine how many VMs should be migrated. By using the experimental system, we found that the control interval has an optimal value, which depends on the management system processing capacity. [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]

Compared with conventional porcelain bushings, polymeric ones are light and therefore possess improved seismic performance. They are also explosion proof with no scattering when broken and are highly stain resistant. In particular, the polymeric bushings coated with silicone rubber show good voltage resistance performance, even when covered with salt deposits. That is, by covering the surface with silicone rubber, the hydrophobic nature of the polymer bushing becomes excellent. This reduces the risk of the occurrence of surface arc discharges and flashovers. Therefore, as shown in Figure 1, the length of a typical polymer bushing insulated with pressurized SF6 can be reduced significantly compared with a conventional porcelain bushing insulated with oil-impregnated paper (OIP) of the same voltage class. The weight can be reduced drastically as well. [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]

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 article calls for papers for the 2012 International Symposium on Antennas and Propagation (ISAP 2012) that will be held in Nagoya, Japan, from October 29 to November 2, 2012.

This article introduces a series of articles related to papers presented at the 2003 Symposium on VLSI Circuits, which was held at the Rihga Royal Hotel, Kyoto, Japan during June 12-14, 2003, published in the April 2004 issue of the IEEE Journal of Solid-State Circuits. The 2003 Technical Program Committees of the Symposium selected 77 papers to be presented. These papers covered a vast scope of digital, analog, memory, signal processing, and wireless and wire-line communication circuits.

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]

An introduction to the journal is presented in which the editor discusses an article on the results of the binary feedback control system, an article on the correlation of cavitation and temperature rise in therapeutic ultrasound, and the International Symposium on Therapeutic Ultrasound (ISTU) to be held on June 2010 in Tokyo, Japan.

Highlights the 9th Spacecraft Charging Technology Conference in Tsukuba, Japan. Papers presented; Spacecraft-plasma interactions; Space plasma science instrumentation.

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]

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]

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 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]

An introduction to the journal is presented in which the guest editors discusses various research papers selected from the Very-Large-Scale Integration (VLSI) Circuits symposium on advancements in semiconductor industry that was held in Kyoto, Japan from June 12 to 14, 2013.

Since its beginning in 1992 in Japan, International Symposium on Semiconductor Manufacturing (ISSM) has provided unique opportunities to share the best practices of semiconductor manufacturing technologies for professionals. At the symposiums, semiconductor manufacturing professionals discussed the technologies developed to meet the worldwide requirements for advanced manufacturing. It is becoming crucial to re-examine semiconductor manufacturing in terms of fundamental principles to improve the performance of semiconductor devices. Moreover, utilizing artificial intelligence and machine learning technologies to improve semiconductor manufacturing have become a new challenge. These manufacturing technology challenges are showing the need for drastic revolutionary concept and stronger collaborative efforts to find solutions to the precompetitive challenges. [ABSTRACT FROM AUTHOR]

Modern society is supported by various technologies such as AI (artificial intelligence), IoT (internet of things), 5G (fifth generation technology standard for cellular networks), etc. Indispensable key components within these technologies are, of course sensors that detect and monitor various physical, chemical, and biological parameters. To monitor mechanical movements, such as vibration and bending, piezoelectric materials can effectively be used. Piezoelectricity is a phenomenon that is observed in a certain kind of dielectric materials and many academic papers in scientific conferences and journals have been devoted to this phenomenon, including publications of IEEE DEI Society [1, 2]. [ABSTRACT FROM AUTHOR]