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IEEE Electronic Components and Technology Conference

作者： Jinwoo Lee Daeil Kwon Department of System Design and Control Engineering UNIST (Ulsan National Institute of Science & Technology) Ulsan Republic of Korea

Electronic systems are exposed to stress conditions during their life cycle. Chemical substances such as moisture and acid are the major source of stresses. The chemical stress condition can induce chemical degradation of electronic components and interconnects including solder joints. Chemical degradation often leads to malfunctions of electronic systems, ultimately resulting in system failure. To monitor damages of the electronic system, measurements based on DC resistance are often used as a system health indicator because they can clearly show the electrical discontinuity. However, DC measurement often requires additional sensing devices or circuitry to detect failure with actual electronic system. This paper introduces a new approach to detect degradation of an electronic system. Using the skin effect of digital signals, we demonstrate that the digital signal enables detection of solder joints degradation under chemical stress condition. We designed an accelerated life test (ALT) to apply chemical stress to solder joints by acid. Digital signal integrity was continuously monitored simultaneously with DC resistance during the ALT to identify the failure precursor of the solder joints. The experimental results indicate that digital signal integrity is gradually deteriorated during solder joint degradation prior to complete electrical open state. The proposed approach based on the digital signal used in the electronic system does not require additional devices. Thus, it is more adaptable than the existing DC measurement in managing the health of actual electronic systems.

关键词： Reliability Signal integrity Interconnect Impeadnce

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Effect of electrostatic charged state on die-wall lubrication for powder metallurgy

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Funtai Oyobi Fummatsu Yakin/Journal of the Japan Society of Powder and Powder Metallurgy 2016年第3期63卷 93-100页

作者： Adachi, Kyoushi Fujiki, Akira R and D Laboratory Adeka Chemical Supply Corporation 7-2-34 Higashiogu Arakawa-ku Tokyo116-0012 Japan Department of Mechanical Control Systems Faculty of System Science and Engineering Shibaura Institute of Technology 307 Fukasaku Minuma-ku Saitama337-8570 Japan

This study was made to investigate the electrostatic adhesion of powder lubricants of various types caused by friction, and the resulting green compact and sintered compact characteristics when the powder lubricant was used as a die-wall lubricant. The powder lubricant like metallic soap containing a functional group that is easily polarized (carboxyl group) in the molecular framework is suitable for use as a die-wall lubricant by electrostatic adhesion. It was shown that the powder lubricant with finer particle size containing easily polarized functional group adheres to the die wall easily. It was also shown that density and transverse rupture strength of the sintered compact increase with increase of coverage of the die surface by the powder lubricant.

关键词： Particle size

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Stabilization of impedance matching system using RF transformer

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IEEJ Transactions on Fundamentals and Materials 2016年第7期136卷 404-408页

作者： Sugimoto, Kazuhiro Watakabe, Mineo Okuno, Masayuki Homma, Tetsuya Functional Control System Graduate School of Engineering and Science Shibaura Institute of Technology 3-7-5 Toyosu Koto-ku Tokyo135-8548 Japan Corporate Technology Center Sunsay Generic Co. Ltd. 2-14 Shingai-cho Fukuyama721-0955 Japan

We have investigated a new dry ashing system for manufacturing of semiconductor devices. For this purpose, we have proposed a plasma system using RF transformer, which is essential to dry ashing, in order to maintain the plasma excitation. This RF transformer can achieve a balanced connection of inductive coil. This system also can improve the ashing uniformity, resulting in high capability for various plasma processing. From the measurement of antenna potential, the deviation of etching rate for balanced connection was reduced to 35%, as compared to that for the unbalanced connection, resulting in improvement of uniformity. By employing an impedance conversion method using RF transformer, the incident signal power can be supplied even though the 25 times higher load impedance than conventional plasma systems. As for the T-type impedance matching using RF transformer, the matching time was reduced to 0.2 s from 8 s for conventional L-type impedance matching system. Wide range impedance matching can be achieved by using T-type impedance matching system. It was confirmed that this system can achieve a stable plasma processing and reduction of ashing process step number, as well as reduction of power consumption and environmental load. © 2016 The institute of Electrical Engineers of Japan.

关键词： Inductively coupled plasma

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Effect of vibration transmissibility on fatigue lifetime of electronic devices

Effect of vibration transmissibility on fatigue lifetime of ...

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International Conference on Industrial engineering, Management science and Applications, ICIMSA 2015

作者： Yang, Liu Chen, Ying Yuan, Zenghui Chen, Liqun Science and Technology on Reliability and Environmental Engineering Laboratory Beihang University Beijing China AVIC Aviation Motor Control System Institute Wuxi Jiangsu China

ISBN: (纸本)9783662471999

Vibration fatigue is one of the main mechanisms which will cause the failures of electronic devices. If the natural frequency of a PCB and its case do not obey octave rule, the vibration of the PCB and the case will couple with each other, and stress applied on PCB will be amplified, resulting in early failure. With Steinberg vibration fatigue prediction models, this paper studies the effect of vibration transmissibility on fatigue lifetime of electronic devices with consideration of coupling. ADAMS software is used to simulate and analyze the vibration transmissibility of electronic devices. The correction of vibration transmissibility in Steinberg model is given. In case study, vibration fatigue lifetimes that compute with corrected Steinberg model and the model without consideration of vibration transmissibility are compared. Effect of vibration transmissibility on electronic devices’ fatigue life is discussed. © Springer-Verlag Berlin Heidelberg 2015.

关键词： Thermoelectric equipment

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Precise carrier phase time transfer based on BDS regional navigation system 66

Precise carrier phase time transfer based on BDS regional na...

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66th International Astronautical Congress 2015: Space - The Gateway for Mankind's Future, IAC 2015

作者： Hongzheng, Cui Liu, Wenling Geshi, Tang Baiyan, Song Huicui, Liu Science and Technology on Aerospace Flight Dynamics Laboratory Beijing Aerospace Control Center China Beijing Institute of Electronic System Engineering Beijing10085 China

ISBN: (纸本)9781510818934

The GNSSCPTT (GNSS Carrier Phase Time Transfer) can provide 0.1∼0.2 ns accuracy and a frequency stability of le-15∼2e-15 for averaging times of half-day, which is equivalent to the two-way satellite time/frequency transfer (TWSTFT). The BDS constellation composed of 14 GEO satellites has deployed by 2012 and begins to provide positioning services for Asia-Pacific region. In order to provide services of GNSS performance monitoring, promote service assurance, improve service performance, ensure the interoperability of OS signals for four systems, GPS/GLONASS/GALILEO/BDS, the iGMAS (international GNSS Monitoring and Assessment Service) is established. BACC is doing the work about operation and maintenance the iGMAS Analysis Center (BAC), and producing the precision products to the users with equivalent accuracy to well-known institutes, such as IGS and CODE, including precise satellite orbit and clock, tracking station coordinate and receiver clock, Zenith Total Delay (ZTD), Earth Orientation Parameter (EOP) parameters, global statistical integrity and Ionospheric map. This paper first describes a prototype of GNSSCPTT involved geodetic Multi-GNSS receiver, choke antenna, reference atomic clock, and other assistant equipment. On the basis of above prototype, we carry out the zero baseline experiment to calibrate the external delay including antenna delay (AE), low noise amplifier delay (LNA), and power splitter delay (PS), and receiver internal delay (RE) using two geodetic Multi-GNSS receivers with the same choke antenna and reference atomic clock. The short and long baseline experiments are also established to validate the short and long distance BDS time transfer accuracy with several long baselines from a network of BDS-capable receivers from the IGS Multi-GNSS Experiment (MGEX) and a regional BDS station network operated by China. Then, in order to analyse the characteristic of BDS carrier phase based time transfer, the observation data from zero and long baseline

关键词： Global positioning system

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Development of database of real-world diesel vehicle emission factors for China

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Journal of Environmental sciences 2015年第5期27卷 209-220页

作者： Xianbao Shen Zhiliang Yao Qiang Zhang David Vance Wagner Hong Huo Yingzhi Zhang Bo Zheng Kebin He State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Tsinghua University School of Food and Chemical Engineering Beijing Technology and Business University Ministry of Education Key Laboratory for Earth System Modeling Center for Earth System Science Tsinghua University International Council on Clean Transportation (ICCT) Institute of Energy Environment and Economy Tsinghua University State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex Tsinghua University

A database of real-world diesel vehicle emission factors, based on type and technology, has been developed following tests on more than 300 diesel vehicles in China using a portable emission measurement system. The database provides better understanding of diesel vehicle emissions under actual driving conditions. We found that although new regulations have reduced real-world emission levels of diesel trucks and buses significantly for most pollutants in China, NOx emissions have been inadequately controlled by the current standards, especially for diesel buses, because of bad driving conditions in the real world. We also compared the emission factors in the database with those calculated by emission factor models and used in inventory studies. The emission factors derived from COPERT（Computer Programmer to calculate Emissions from Road Transport） and MOBILE may both underestimate real emission factors, whereas the updated COPERT and PART5（Highway Vehicle Particulate Emission Modeling Software） models may overestimate emission factors in China. Real-world measurement results and emission factors used in recent emission inventory studies are inconsistent,which has led to inaccurate estimates of emissions from diesel trucks and buses over recent years. This suggests that emission factors derived from European or US-based models will not truly represent real-world emissions in China. Therefore, it is useful and necessary to conduct systematic real-world measurements of vehicle emissions in China in order to obtain the optimum inputs for emission inventory models.

关键词： Diesel vehicle Emission factor Portable emission measurement system Database China

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Trends of Extreme Precipitation in Eastern China and Their Possible Causes

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Advances in Atmospheric sciences 2015年第8期32卷 1027-1037页

作者： LIU Run LIU Shaw Chen Ralph J.CICERONE SHIU Chein-Jung LI Jun WANG Jingli ZHANG Yuanhang State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering Peking University Research Center for Environmental Changes Academia Sinica Department of Atmospheric Science NCU National Academy of Sciences Earth System Science University of California Institute of Urban Meteorology of China Meteorological Administration

Significant increases of heavy precipitation and decreases of light precipitation have been reported over widespread regions of the globe. Global warming and effects of anthropogenic aerosols have both been proposed as possible causes of these changes. We examine data from urban and rural meteorological stations in eastern China （1955-2011） and compare them with Global Precipitation Climatology Project （GPCP） data （1979-2007） and reanalysis data in various latitude zones to study changes in precipitation extremes. Significant decreases in light precipitation and increases in heavy precipitation are found at both rural and urban stations, as well as low latitudes over the ocean, while total precipitation shows little change. Characteristics of these changes and changes in the equatorial zone and other latitudes suggest that global warming rather than aerosol effects is the primary cause of the changes. In eastern China, increases of annual total dry days （28 days） and ） 10 consecutive dry days （36%） are due to the decrease in light precipitation days, thereby establishing a causal link among global warming, changes in precipitation extremes, and higher meteorological risk of floods and droughts. Further, results derived from the GPCP data and reanalysis data suggest that the causal link exists over widespread regions of the globe.

关键词： extreme precipitation global warming aerosols meteorological risk of floods and droughts

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Power efficiency and loss in push-pull MOS-FET DC-to-RF power inverter for plasma generator

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IEEJ Transactions on Industry Applications 2016年第8期136卷 511-521页

作者： Sugimoto, Kazuhiro Hamaoka, Junji Okuno, Masayuki Sako, Kunihiro Homma, Tetsuya Functional Control System Graduate School of Engineering and Science Shibaura Institute of Technology 3-7-5 Toyosu Koto-kuTokyo135-8548 Japan Corporate Technology Center Sunsay Generic Co. Ltd. 2-14-3 Shingai-cho FukuyamaHiroshima721-0955 Japan

This paperdescribes the power efficiency and losses in push-pull MOS-FET arrays in an inverter for a plasma generator. The inverter consists of parallel connected MOS-FETs and the output powertransformer. The power losses within the MOS-FET arrays and output power transformer are estimated based on their thermal resistances, which were obtained separately by measurements. The drain efficiency was thus obtained from the DC input power, RF output power, and estimated power losses. The output power of the MOS-FET arrays was 1 kW, with a drain efficiency of 79% and at 13.56 MHz, when the DC voltage was 48 V. © 2016 The institute of Electrical Engineers of Japan.

关键词： Efficiency

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26th Annual Computational Neuroscience Meeting (CNS*2017): Part 3 Antwerp, Belgium. 15-20 July 2017 Abstracts

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BMC NEUROscience 2017年第SUPPL 1期18卷 95-176页

作者： [Anonymous] Department of Neuroscience Yale University New Haven CT 06520 USA Department Physiology & Pharmacology SUNY Downstate Brooklyn NY 11203 USA NYU School of Engineering 6 MetroTech Center Brooklyn NY 11201 USA Departament de Matemàtica Aplicada Universitat Politècnica de Catalunya Barcelona 08028 Spain Institut de Neurobiologie de la Méditerrannée (INMED) INSERM UMR901 Aix-Marseille Univ Marseille France Center of Neural Science New York University New York NY USA Aix-Marseille Univ INSERM INS Inst Neurosci Syst Marseille France Laboratoire de Physique Théorique et Modélisation CNRS UMR 8089 Université de Cergy-Pontoise 95300 Cergy-Pontoise Cedex France Department of Mathematics and Computer Science ENSAT Abdelmalek Essaadi’s University Tangier Morocco Laboratory of Natural Computation Department of Information and Electrical Engineering and Applied Mathematics University of Salerno 84084 Fisciano SA Italy Department of Medicine University of Salerno 84083 Lancusi SA Italy Dipartimento di Fisica Università degli Studi Aldo Moro Bari and INFN Sezione Di Bari Italy Data Analysis Department Ghent University Ghent Belgium Coma Science Group University of Liège Liège Belgium Cruces Hospital and Ikerbasque Research Center Bilbao Spain BIOtech Department of Industrial Engineering University of Trento and IRCS-PAT FBK 38010 Trento Italy Department of Data Analysis Ghent University Ghent 9000 Belgium The Wellcome Trust Centre for Neuroimaging University College London London WC1N 3BG UK Department of Electronic Engineering NED University of Engineering and Technology Karachi Pakistan Blue Brain Project École Polytechnique Fédérale de Lausanne Lausanne Switzerland Departement of Mathematics Swansea University Swansea Wales UK Laboratory for Topology and Neuroscience at the Brain Mind Institute École polytechnique fédérale de Lausanne Lausanne Switzerland Institute of Mathematics University of Aberdeen Aberdeen Scotland UK Department of Integrativ

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Response to Comments by Yuan WANG on “Trends of Extreme Precipitation in Eastern China and Their Possible Causes”

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Advances in Atmospheric sciences 2015年第10期32卷 1447-1448页

作者： LIU Run LIU Shaw Chen Ralph J.CICERONE SHIU Chein-Jung LI Jun WANG Jingli ZHANG Yuanhang State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and EngineeringPeking University Research Center for Environmental Changes Academia Sinica Department of Atmospheric Science NCU National Academy of Sciences Earth System Science University of California Institute of Urban Meteorology of China Meteorological Administration

In his comments, Wang cites a number of works to dispute the conclusion in our previous work, which attributes the observed decreases/increases in light/heavy precipitation in eastern China primarily to global warming rather than the regional aerosol effect. However, most of the cited works （admittedly, including our previous work）, employ correlation analysis, which has little bearing on the cause--effect relationship. Theoretical analyses and/or modeling studies are needed to ascertain the cause-effect relationship. We argue that theoretical analyses and modeling results show that global warming is the primary cause of the widely observed phenomena of suppression of light precipitation and enhancement of heavy precipitation across the globe, including in eastern China.

关键词： extreme precipitation global warming aerosols

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