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Akihito OTANI, Tadahiro SHIBUTANI, Masaki MORISHITA, Izumi NAKAMURA, T ...
Session ID: F08104
Published: 2019
Released on J-STAGE: March 25, 2020
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Akihito OTANI, Izumi NAKAMURA, Tomoyoshi WATAKABE, Masaki MORISHITA, T ...
Session ID: F08105
Published: 2019
Released on J-STAGE: March 25, 2020
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Izumi NAKAMURA, Masaki MORISHITA, Akihito OTANI, Tadahiro SHIBUTANI, T ...
Session ID: F08106
Published: 2019
Released on J-STAGE: March 25, 2020
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Shuuichi UMEZAWA
Session ID: F08201
Published: 2019
Released on J-STAGE: March 25, 2020
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Shuichi Umezawa, Kazushi Miyata
Session ID: F08202
Published: 2019
Released on J-STAGE: March 25, 2020
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A clamp-on type flowmeter for steam and air, which does not require pipe-cutting for installation, is needed for diagnosing performance and saving energy in facilities such as factories and power plants. Therefore, in our previous study we devised a heater method for measuring steam and air flow, in which a circumferential heater was attached to the outside of a pipe and then the axial temperature distribution on the outside of the pipe was measured by thermocouples. Steam velocity was analyzed on the basis of the temperature distribution in the pipe axial direction, considering heat transfer inside the pipe and thermal conductivity in the steel pipe-wall. In this study, simulation was performed on the operation of the steam flow meter and a simple method for the prediction of steam velocity with the flow meter was discussed.
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Yuta UCHIYAMA, Ryo MORITA, Shuichi UMEZAWA, Katsuhiko SUGITA
Session ID: F08203
Published: 2019
Released on J-STAGE: March 25, 2020
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The act of evaluating steam flow rate at demand end is significant in the point of view of energy management since the steam is widely used to thermal energy supply in the industrial fields. The steam state of the practical steam piping of the factories can be a wet steam as a consequence of heat loss, heat supply, work, and so forth. It is well known that the steam wetness sometimes causes measurement errors of steam flow meter. However, there has been no established standard for estimating the measurement error since it is hard to evaluate the effects of the steam wetness quantitatively in plants and factories. A clamp-on type ultrasonic steam flow meter now under development is useful for the factory since it is unnecessary to pipe processing. We have performed the steam flow test with this clamp-on type ultrasonic flow meter and found some characteristics of the indicated value of flow rate. This paper introduces evaluation of the characteristics of the measured flow rate by the clamp-on type ultrasonic flow meter under the wet steam flow in the large-bore piping than our previous studies.
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Tatsuya FUNAKI
Session ID: F08204
Published: 2019
Released on J-STAGE: March 25, 2020
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Tatsuya FUNAKI
Session ID: F08205
Published: 2019
Released on J-STAGE: March 25, 2020
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Takehiro NISHIMURA, Go MATSUBARA, Fumihide INAMURA, Yousuke TSUMURA
Session ID: F10101
Published: 2019
Released on J-STAGE: March 25, 2020
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The efWING is a railway vehicle truck developed as a new generation truck. The feature is that it has CFRP Leaf Spring, achieving significant weight reduction and improvement of running performance. This document describes the development process and the features of efWING, and also describes the operational service examples.
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Shogo KAMOSHITA, Yasuhiro UMEHARA, Mitsugi SUZUKI, Tadashi IIDA, Takat ...
Session ID: F10102
Published: 2019
Released on J-STAGE: March 25, 2020
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The authors developed the bogie for reducing risk of derailment. The bogie can control the decrement of the wheel load and equipped with a steering system that reduces the lateral force for the purpose of preventing the flange climb derailment. The bogie frame is composed of three blocks that are cross beam, right and left side beams, and they are joined together via a rotation mechanism in pitching direction. Since the bogie frame can follow the twist of a track by rotating the side beams with the rotation mechanism. The bogie is also equipped with a steering device that is referred to as an “Assist steering system”. It is composed of pneumatic actuators built into mono-links, a mechanical sensor to detect the bogie angle from the relative movement between the bogie and the car body, and a pneumatic valve that works according to the sensing device. The authors confirmed the satisfactory performance of the bogie in the operating speed range using a test line of the MIHARA TEST CENTER.
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(Innovation of the resistance spot welding and the laser welding for stainless steel vehicles)
Masashi OIKAWA, Hayato YONEMORI, Atsushi UENO, Shigeki MATSUOKA
Session ID: F10103
Published: 2019
Released on J-STAGE: March 25, 2020
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Currently, the domestic market share of stainless steel vehicles has reached approximately 60%. Japan's first stainless steel vehicle was the Tokyu Corporation 5200 series manufactured by Tokyu Car Co., Ltd. in 1958. Since then, with the continuous innovation, weight reduction, high rigidity and high strength of stainless steel vehicles have been carried out. The elemental technologies that make up the vehicle structure include design technology, material technology and processing technology, and welding technology is one of the processing technologies. Among these, this paper describes t innovations in resistance spot welding technology and laser welding technology of stainless steel vehicles, and also points out direction of the future innovation.
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Takeshi KAWASAKI
Session ID: F10104
Published: 2019
Released on J-STAGE: March 25, 2020
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This paper describes railway carbody shell made of aluminium alloy, and “Single” and “Double” skin structures are introduced as representative achievements. For worldwide application, crashworthy structure is developed.
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Akihiko Tori
Session ID: F10105
Published: 2019
Released on J-STAGE: March 25, 2020
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In 1962, just before the commencement of Tokaido Shinkansen, research on a linear motor propulsion magnetically levitated system began as the next-generation ultra-fast link between Tokyo and Osaka with a journey time of 1 hour by the informal interest group named "Dream" in Japan National Railway's Laboratory. Now, the dream has come true and construction of the Superconducting Maglev Chuo Shinkansen is in progress. Yamanashi Maglev Line started running tests in April 1997 and all technologies required for commercial services have been developed. In the spring of 2020, a new vehicle, which is a brushed-up version of Series L0, would be produced. Timeline to progress of the Maglev technology is summarized.
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[in Japanese]
Session ID: F10106
Published: 2019
Released on J-STAGE: March 25, 2020
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Osamu UMEZAWA, Shinichi TAKAGI
Session ID: F11101
Published: 2019
Released on J-STAGE: March 25, 2020
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Nitrided layer formed on a steel consists of Fe2-3N (ε) and/or Fe4N (γ’) surface compound layer and diffusion layer with high solute nitrogen and/or γ’ precipitates. Fatigue strength significantly depends on crystal structure of surface compound layer. Nitrided SCZM435 steel with γ’ phase dominant showed substantially high fatigue strength comparing to that with ε phase dominant. A number of cracks was detected in the γ’ compound layer of nitrided low carbon steels in both tensile and cyclic deformation. In the case of tensile test, the cracks were generated from the interface between γ’ compound layer and matrix. The cracks mostly grew in the γ’ compound layer as {001} transgranular-type. The hard γ’ compound can hardly accommodate a large plastic deformation in the matrix. The <001> orientation exhibits the lowest Young’s modulus. Therefore, the stress concentration at the interface in tension may cause the cracking in the γ’ compound. On the other hand, the fatigue cracks were initiated at the specimen surface, the microcracks were {111} transgranulartype. A large number of slip traces were installed in the γ’ compound layer even at low cyclic stress level. Dislocation structure near the crack in the γ’ compound layer was planar, and dislocation density was high. Thus, plastic deformation in γ’ grains may predominate the fatigue crack initiation and its growth.
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Masahiro Kada
Session ID: F11102
Published: 2019
Released on J-STAGE: March 25, 2020
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Polyacetal is a very suitable resin for use as a gear because it has good sliding properties, fatigue properties, heat resistance, dimensional stability, high precision. In addition, polyacetals can be used without reinforcement with glass fibers since the decrease in elastic modulus is small at high temperatures. Therefore, it is possible to use it as a gear even at high temperatures while maintaining the wear resistance and high precision of polyacetal. These are the technical backgrounds that polyacetal monopolizes the resin gear market for many years. Another major reason is that polyacetal can be supplied at a reasonable cost. 50 years have passed since polyacetal was put on the market, and there is no alternative resin yet. In this report, these are explained using data respectively.
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Kazuaki NISHIYABU, Shigeo TANAKA
Session ID: F11103
Published: 2019
Released on J-STAGE: March 25, 2020
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A micro-planetary gear made of stainless steel has been developed by micro metal powder injection molding (μ-MIM) process. In this study, the accuracy and the quality of ultra-compact planet gear (module: m=0.07mm, number of teeth: z=24) was evaluated. Cross-sections of the gear teeth were observed with a digital microscope and dimensions of the teeth were measured with a digital image processing. The variations in dimensions and shape of gear teeth were systematically investigated for mold, green and sintered parts, and heat treated ones. The accuracy classes of the ultra-compact planet gear were defined from four shape variations of gear teeth, i.e. total runout, single pitch deviation, accumulated pitch deviation and tooth profile deviation. The accuracy class was concluded as JIS N class seven which is a comparatively high precise level for practical applications.
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Akihiro Yamamoto, Shingo Higashiyama, Motoki Yashiroda
Session ID: F11104
Published: 2019
Released on J-STAGE: March 25, 2020
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Since cellulose nanofibers are made from wood, it is possible to utilize Japanese forest resources. In addition, because it has various characteristics, research is being conducted for the purpose of industrial use. Recently, we are trying to use it as a resin reinforcement material by making use of the excellent strength and nanofiber shape of cellulose nanofibers. In this research, we knead and disperse to polypropylene, which is a general-purpose resin, by various methods using mechanical lignocellulosic nanofibers, and confirmed the dispersion behavior of cellulose nanofibers and the change in physical property value given to polypropylene The In order to develop a structure with higher strength, a compact of only lignocellulose nanofibers was produced and its characteristics were confirmed.
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-Ultra-flexible and stretchable solar cells-
Kenjiro Fukuda, Zhi Jiang, Kilho Yu, Steven Rich, Takao Someya
Session ID: F11202
Published: 2019
Released on J-STAGE: March 25, 2020
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Hiroshi ITO, [in Japanese], [in Japanese]
Session ID: F11205
Published: 2019
Released on J-STAGE: March 25, 2020
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Souichi TOYAMA
Session ID: F11301
Published: 2019
Released on J-STAGE: March 25, 2020
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In this paper, I present a user case study of the advanced 1DCAE (Modelica) software "MapleSim", system-level modeling and simulation environment, in order to model a CNC machine tool in high fidelity. “MapleSim” enables interdisciplinary engineering-design team of high precision mechatronic products such as the FA equipment to accomplish appropriate teamwork and solve their design problems systematically.
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[in Japanese]
Session ID: F11302
Published: 2019
Released on J-STAGE: March 25, 2020
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Jun Geirin
Session ID: F11303
Published: 2019
Released on J-STAGE: March 25, 2020
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Hiroshi Takata
Session ID: F18101
Published: 2019
Released on J-STAGE: March 25, 2020
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Kosei ISHIMURA, Taro KAWANO, Ayako TORISAKA, Akihiro DOI, Hideyuki FUK ...
Session ID: F19101
Published: 2019
Released on J-STAGE: March 25, 2020
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For future advanced missions, large and highly accurate space structures are required. A prior shape adjustment of the structure before launch is not sufficient to achieve such accurate space structures. For example, thermal deformation on orbit cannot be eliminated by the preliminary adjustment of the structure. Therefore, the shape control of the structure is a promising technique for highly accurate space structures. For the shape control, the shape error should be measured on-orbit. In this study, a measurement system for the displacement of a slender space structure has been developed as an alignment monitor. The characteristics of this measurement system are long working distance and simple configuration. The measurement system consists of a laser, retro-reflector and positioning sensing device. The performance on the ground was already demonstrated through the satellite ground test. As a first step to on-orbit experiment, the demonstration experiment on the balloon is planned. In this paper, the system configuration and development progress are reported.
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Naoko KISHIMOTO
Session ID: F19102
Published: 2019
Released on J-STAGE: March 25, 2020
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Yoya GON, Nozomu KOGISO
Session ID: F19103
Published: 2019
Released on J-STAGE: March 25, 2020
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This paper summarizes our research conducting on deployment repeatability analysis of an extensible optical bench (EOB) that is used for a highly precise large space telescope. Under strict design requirement for pointing accuracy, effect of uncertainties exist in the assembled EOB cannot be ignored. At first, an uncertainty estimation method for pointing performance is proposed by investigating effects of three kind of physical uncertainties related to the structural performance as a member length uncertainty, backlash and friction uncertainties at connecting nodes on the pointing performance. Then, deployment repeatability analysis is proposed, where an effect of a friction at the connecting nodes on the position of the node is evaluated simply as perturbation from the equilibrium condition. Finally, the future problem of our research is discussed.
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Hidehiro HATA
Session ID: F19104
Published: 2019
Released on J-STAGE: March 25, 2020
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Hiroaki TANAKA
Session ID: F19105
Published: 2019
Released on J-STAGE: March 25, 2020
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High accuracy space structure systems by using smart structures were investigated. A smart reconfigurable reflector system was developed and its performance was investigated. The effectiveness of the smart reconfigurable reflector was demonstrated through experiments using an antenna system. Piezoelectric materials are known as potential candidate to use as the sensor and actuator. In order to investigate effects of space environment on piezoelectric material, PiezoElectric
Actuator Characteristic Experiments (PEACE) was proposed and the flight model was developed.
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Keiichi WATANUKI
Session ID: F25101
Published: 2019
Released on J-STAGE: March 25, 2020
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(A Theory of Relativity of Perception)
Hideyoshi YANAGISAWA
Session ID: F25102
Published: 2019
Released on J-STAGE: March 25, 2020
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Naomi ARAKAWA
Session ID: F25106
Published: 2019
Released on J-STAGE: March 25, 2020
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Tomoaki OHTSUKI
Session ID: F25200
Published: 2019
Released on J-STAGE: March 25, 2020
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In modern society, communication has become an indispensable part of life as social infrastructure. In addition to voice, various kinds of data are exchanged over wired and wireless networks. Recently, the 5th generation mobile communication system (5G), which is scheduled to start some services in 2019 in Japan, is attracting much attention. In this article, we briefly introduce 5G and the future image of mobile communications beyond 5G that has already been studied. This article is an excerpt of that published in the special issue of the 6th issue of the Journal of The Japan Society of Mechanical Engineers, “Kikai in the age of 5G・IoT”.
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Ryoichi Shinkuma
Session ID: F25201
Published: 2019
Released on J-STAGE: March 25, 2020
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This talk discusses autonomous network systems applicable for disaster-hit Situations. Particularly, two research works which the speaker did before are introduced in talk. The first topic is that a design of ad hoc wireless mesh networks formed by unmanned aerial vehicles (UAVs) with advanced mechanical automation. This work studies a range of network architectures that depend on the mechanized automation (Access Point separation and battery replacement) capabilities of UAVs and proposes heuristic UAV scheduling algorithms for each network architecture, which are benchmarked against optimal designs. The second topic is a scheduling method of multi-UAV search systems that takes into account both the processing time of image data and the data transfer time. It presents a utility-based problem formulation that ensures continuously updating information while obtaining as many pieces of information as possible for a certain period. The simulation results indicate that the proposed scheduling method maximizes user utility and performs better than a conventional scheduling method in terms of user-centric evaluation metrics.
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Tomoharu ANDO
Session ID: F25204
Published: 2019
Released on J-STAGE: March 25, 2020
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Hiroaki MORINO
Session ID: F25205
Published: 2019
Released on J-STAGE: March 25, 2020
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Keiichi WATANUKI
Session ID: F25206
Published: 2019
Released on J-STAGE: March 25, 2020
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Kazuhiko NOGUCHI
Session ID: F25401
Published: 2019
Released on J-STAGE: March 25, 2020
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In the high technology society, there are various potential risks. In such a society, it is difficult to construct a dynamic and safe society by means of reducing individual risks. In order to build a desirable society in a society where various risks are latent, it is necessary to create a society using the concept of risk symbiosis.
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Etsuya SHIBAYAMA
Session ID: F25402
Published: 2019
Released on J-STAGE: March 25, 2020
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We present characteristics and risks of systems and technologies based upon AI (Artificial Intelligence), BD (Big Data), and IoT (Internet of Things) that we expect to make our society smarter and more connected. In general, a society is an inherently connected system, and so connectedness or interdependence is inevitable. AI and IoT in combination with BD probably generate more dependencies among social components for good reason. Those dependencies as well as the nature of the Internet, that is, the lack of central authorities make the system more complex and complicated. It is hard to design, understand or reason about such a system. In addition, we face cyberattacks and cyberterrorism and should overcome the fear of AI. For maximizing the benefits and minimizing costs and risks, we should provide comprehensible and manageable descriptions of our smart and connected society, continue to discuss the future with smart machines, and embrace rapid changes.
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Masao MUKAIDONO
Session ID: F25403
Published: 2019
Released on J-STAGE: March 25, 2020
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Review the recent trends in safety and introduce new technologies and concepts, Safety 2.0 and the concept of harmonious safety, as a development process of the history of safety technology in it.
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Noboru Takizawa
Session ID: J01101
Published: 2019
Released on J-STAGE: March 25, 2020
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It has been studied self-heating of the switching element of the switching converter, bat it's only the ON resistance and switching loss of the switching element. In this paper, it has been confirmed that the self-heating of the switch element increases in the case of verification including the characteristic variation due to the heat reception and the self-heating of the inductor. -
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Toru IKEDA, Takumi SASAKI, Masaaki KOGANEMARU, Atsushi YANASE, Dai OKU ...
Session ID: J01102
Published: 2019
Released on J-STAGE: March 25, 2020
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Masaaki KOGANEMARU, Kazuya HIDAKA, Koki SHIOTSUKA, Toru IKEDA, Satoshi ...
Session ID: J01103
Published: 2019
Released on J-STAGE: March 25, 2020
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Hayato NIWA, Risako KIBUSHI, Noriyuki UNNO, Kazuhisa YUKI
Session ID: J01104P
Published: 2019
Released on J-STAGE: March 25, 2020
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This study describes the evaluation of thermal contact resistance under high heat flux. Next-generation semiconductor devices have advantage, which are high voltage device, and can be used under very high temperature and high heat flux. The contact thermal resistance of TIM (Thermal Interface Material) used at high temperature, thus, should be evaluated. Ag paste is expected as TIM used at high temperature. In this study, the contact thermal resistance is experimentally evaluated by steady state method. The experimental apparatus has heat transfer surface of φ 20.0 mm, and applied contact pressure to the heat transfer surface is 0.09 MPa. The results show that the temperature gap between the heat transfer surfaces show complete different tendency before / after solidification of the Ag paste.
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Ryota MIZUNO, Ken SUZUKI, Hideo MIURA
Session ID: J01106P
Published: 2019
Released on J-STAGE: March 25, 2020
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In this study, micro-scale strain sensors embedded in a silicon chip were developed in order to measure the local stress distribution in 3D semiconductor modules. This sensor utilized piezoresistive effect of single crystal silicon. The stress sensitivity at room temperature was 1.3 MPa/ and the stable operation of this sensor was confirmed in the temperature range from room temperature to 80oC at most. The stress distribution in a fine bump structure was measured using this sensor chip. The local distribution of the residual stress in a test 3D structure with various pitches of fine bumps was investigated. It was confirmed that the magnitude of the local deformation of the stacked chips varied a lot depending on the pitch of bumps. The magnitude of the residual stress increased monotonically with the pitch of bumps. Since the electronic performance of semiconductor devices is varied by mechanical stress, it is significantly important to control the stress distribution in complex 3D semiconductor modules for assuring high reliability.
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Takuya KIDO, Mahjabin TASKIN, Ting PAN, Yusei YAMAMOTO, Masahiro INOUE ...
Session ID: J01207
Published: 2019
Released on J-STAGE: March 25, 2020
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Replacement of He gas from N2 in a new gas pipeline was observed using ultrasound from exterior of a pipe. Measurement of gas concentration using ultrasound utilizes difference of sound velocity in various gases. At the time of new hydrogen pipeline construction, the air in the pipe is first replaced with N2 and then with H2 to prevent from explosion. In this study, N2 was replaced with He instead of H2 for safety reason. It is found that the progress of gas replacement depends on the pipe inclination and the outlet. When the outlet direction was facing upward, it was difficult to replace 100%, however, the replacement can be considerably achieved by creating a flow resistance at the outlet. By using this ultrasonic method, the transporting gas concentration in the pipe can be safely monitored from the outside of the pipe without making a hole. The amount of N2 and H2 gas required for replacement can be minimized. This study will be useful for establishment of a safe H2 gas concentration measurement and efficient gas replacement in the gas pipelines.
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Atsuhiko TERADA, Ryutaro HINO
Session ID: J01208
Published: 2019
Released on J-STAGE: March 25, 2020
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Hisayoshi TSUKIKAWA, Masahiro INOUE
Session ID: J01209
Published: 2019
Released on J-STAGE: March 25, 2020
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Shinnosuke NISHIKI
Session ID: J01210
Published: 2019
Released on J-STAGE: March 25, 2020
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Hiroaki KOBAYASHI, Yu DAIMON, Keiichiro FUJIMOTO, Hiroumi TANI, Yusuke ...
Session ID: J01211
Published: 2019
Released on J-STAGE: March 25, 2020
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In this paper, we report the examination situation about the hypothesis that cavitation (bubble collapse) is the ignition source. Cavitation occurs due to sudden change of pressure and temperature of fluid, causes structural damage to the inner surface of the piping and the pump. There were some cases in which this cavitation is presumed to be the cause of hydrogen self-ignition, and experiments are being conducted to clarify the phenomenon. By the previous examination, the hypothesis that hydrogen ignited by the bubble collapse caused by the pressure and temperature change of the fluid was rejected. At present, we are conducting experiments to test hypotheses that bubble collapse caused by impact from droplets is the ignition source.
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