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Technical Development of Simple Shear Deformation Experiments Using a Deformation-DIA Apparatus

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Journal of Earth Science 2010年第5期21卷 523-531页

作者： Tomohiro Ohuchi Takaaki Kawazoe Norimasa Nishiyama Yu Nishihara Tetsuo Irifune Geodynamics research Center Ehime University Senior research fellow Center Ehime University

Technical developments for simple shear deformation experiments at high pressures were made. The newly designed cell assembly can be compressed by deformation-DIA apparatuses with the MA 6-6 system, which consists of six second-stage tungsten carbide anvils （with a truncated edge length of 5 mm） and the anvil guide. Deformation of samples was barely observed during the compression process, showing that the shear strain of the deformed samples can be measured by the rotation of a strain marker. Simple shear deformation experiments on anhydrous and hydrous oli- vine aggregates were conducted under upper mantle conditions （pressures of 5.2-7.6 GPa and temperatures of 1 473-1 573 K）, and sample deformation with a shear strain of 7=0.8-1.2 was successfully achieved at a shear strain rate of 4.0×10^-5-7.5×10^-5 s^-1. The present study extended the pressure range of simple shear deformation experiments in the deformation-DIA apparatus from 3 GPa in an early study to 7.6 GPa at high temperatures.

关键词： simple shear deformation deformation-DIA MA 6-6 upper mantle.

Velocity Profiles between Two Baffles in a Shell and Tube Heat Exchanger

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Journal of Thermal Science 2015年第4期24卷 356-363页

作者： Tae-Hyun Chang Chang-Hoan Lee Hae-Soo Lee Kwon-Soo Lee Senior research fellow of RESEAT Korea Institute of Science and Technology Information Korea Institute of Science and Technology Information Postdoctoral research fellow School of Mechanical Engineering of Kyungnam University International University of Korea

Heat exchangers are extensively utilized for waste heat recovery,oil refining,chemical processing,and steam *** this study,velocity profiles are measured using a 3D particle image velocimetry(PIV)system between two baffles in a shell and tube heat exchanger for parallel and counter *** PIV and computational fluid dynamics results show the occurrence of some strong vectors near the *** vectors are assumed due to the clearance between the inner tubes and the front ***,the major parts of the vectors are moved out through the bottom opening of the rear baffle,and other vectors produce a large circle between the two *** simulations are conducted to investigate the effects of the baffle on the heat exchanger using the Fluent *** k-εturbulence model is employed to calculate the flows along the heat exchanger.

关键词： Baffle P1V Shell and tube heat exchanger Cut off ratio CFD

Higher-mode effect on the seismic responses of buildings with viscoelastic dampers

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Earthquake Engineering and Engineering Vibration 2002年第1期1卷 119-129页

作者： Meng-Hao Tsai Department of Civil Engineering Taiwan UniversityChinese Taipei Postdoctoral Research Fellow

In conventional modal analysis procedures,usually only a few dominant modes are required to describe the dynamic behavior of multi-degrees-of-freedom *** number of modes needed in the dynamic analysis depends on the higher-mode contribution to the structural response,which is called the higher-mode *** modal analysis approach, however,may not be directly applied to the dynamic analysis of viscoelastically damped *** is because the dynamic properties of the viscoelastic dampers depend on their vibration ***,the structural stiffness and damping contributed from those dampers would be different for each *** this study,the higher-mode effect is referred to as the response difference induced by the frequency-dependent property of viscoelastic dampers at higher *** analysis procedures for buildings with viscoelastic dampers distributed proportionally and non-proportionally to the stiffness of the buildings are developed to consider the higher-mode *** studies on shear-type viscoelastically damped building models are conducted to examine the accuracy of the proposed procedures and to investigate the significance of the higher-mode effect on their seismic *** damper models are used to estimate the peak damper forces in the proposed procedures. Study results reveal that the higher-mode effect is significant for long-period viscoelastically damped *** higher-mode effect on base shear is less significant than on story acceleration *** difference of the seismic response usually occurs at the top ***,the higher-mode effect may not be reduced by decreasing the damping ratio provided by the viscoelastic *** practical application,it is realized that the linear viscous damping model without considering the higher-mode effect may predict larger damper forces and hence,is on the conservative side.

关键词： model analysis viscoelastic dampers higher-mode effect

Mapping urban building stocks for vulnerability assessment preliminary results

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International Journal of Digital Earth 2011年第S01期4卷 117-130页

作者： Keiko Saito Robin Spence Department of Architecture University of CambridgeCambridgeUK Cambridge Architectural research Ltd CambridgeUK Willis research fellow Willis Research Network

This paper discusses a methodology to collect building inventory data by combining image processing techniques,field work or tools such as Google Street View and applying statistical *** the methodology outlined in Marinescu(2002),a family of Gabor filters are first constructed,which are then applied to an optical high-resolution *** output from the processed image is segmented using Self-Organising *** paper examines the relationship between the segmented areas in the image and the building type distribution within each segmented area,by deriving the distribution from field *** relationship between the average number of buildings in these cells against the number of grid cells allocated to each segmentation cluster is also ***,using these results,the overall building inventory distribution for the whole of the case study site of Pylos is presented.

关键词： building inventory data collection remote sensing high-resolution optical satellite images Gabor filters Self-Organising Maps field data

Hydrogen technologies and developments in Japan

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Clean Energy 2019年第2期3卷 105-113页

作者： Shigeki Iida Ko Sakata Director The Institute of Applied Energy Executive research fellow The Institute of Applied Energy

The successful development of hydrogen-energy technologies has several advantages and ***-energy development could prevent global warming as well as ensure energy security for countries without adequate energy *** successful development of hydrogen would provide energy for transportation and electric *** is a unique energy carrier,as it can be produced from various energy sources such as wind,fossil fuels and biomass and,when it is combusted,it emits no CO_(2)*** other advantage is the wide distribution of resources globally that can be used to produce *** Japan,the Ministry of Economy,Trade and Industry(METI)published a‘Strategic Roadmap for Hydrogen and Fuel Cells’in 2014,with a revised update published in March *** goal of the roadmap is to achieve a hydrogen *** roadmap aims to resolve technical problems and secure economic *** roadmap has been organized into the following three phases:Phase 1-Installation of fuel cells;Phase 2-Hydrogen power plant/mass supply chain;Phase 3-CO_(2)-free *** paper reports on the current status of fuel cells and fuel-cell vehicles in Japan and gives a description and status of the R&D programmes along with the results of global energy model study towards 2050.

关键词： hydrogen and fuel cell energy system and policy energy and environment energy storage

Velocity Profiles between Two Baffles in a Horizontal Circular Tube

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Journal of Thermal Science 2014年第6期23卷 544-551页

作者： Tae-Hyun Chang Hae-Soo Lee Keon-Je Oh Doeg Hee Doh Chang-Hoan Lee Senior research fellow of RESEAT Korea Institute of Science and Information Postdoctoral research fellow School of Mechanical Engineering of Kyungnam University School of Mechanical Engineering Kyungnam University Division of Mechanical and Energy Systems Engineering Korea Marine and Ocean University Korea Institute of Science and Technology Information

The shell and tube heat exchanger is an essential part of a power plant for recovering heat transfer between the feed water of a boiler and the wasted *** baffles are also an important element inside the heat *** materials influence the flow pattern in the *** influence of baffles in the velocity profiles was observed using a three-dimensional particle image velocimetry around baffles in a horizontal circular *** velocity of the particles was measured before the baffle and between them in the test *** show that the flows near the front baffle flow were parallel to the vertical wall,and then concentrate on the upper opening of the front *** flows circulate in the front and rear *** flow profiles are related to the Reynolds number(Re) or the flow *** velocity profiles at lower Re number showed a complicated mixing,concentrating on the lower opening of the rear baffle as front *** flow was employed in this study,which was produced using tangential velocities at the *** the entrance of the front baffle,the velocity vector profiles with swirl were much different from that without ***,velocities between two baffles are not much different from those without swirl.

关键词： Baffle Shell and tube Tangential inlet Swirl Particle image velocimetry

Rethinking Fast Growth in China's Foreign Exchange Reserves

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China & World Economy 2006年第2期14卷 56-66页

作者： Yuanlong Wang research fellow Bank of China Beijing China.

The sustained surpluses in the current and capital accounts of balance of payments are the main reason for the continuing rapid expanse of China＇s foreign exchange reserves in recent years. However, flaws in the formation of the renminbi exchange rate regime are the institutional root cause of the sustained high growth in foreign exchange reserves. Various theoretical misconceptions about the scale of foreign exchange reserves have swayed policies and contributed to its sustained fast growth. Sustained high growth of China＇s foreign exchange reserves, and its extraordinary large scale, carry tremendous risks. Because the security of foreign exchange reserves affects a country＇s financial safety, China urgently needs to adjust its foreign exchange reserve policies.

关键词： foreign exchange reserve policy adjustment theoretical misconception

Optimal Rocket Trajectories:Singular Control

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Optimal Rocket Trajectories:Singular Control

Effect of near-fault earthquake on bridges:lessons learned from Chi-Chi earthquake

第二十七届中国控制会议

作者： Goh Beansan Visiting research fellow Mathematics DeptXidian University

ISBN: (纸本)9787900719706

This is a brief review of singular optimal rocket trajectories and necessary conditions for their *** are two forms of the compact Goh-Legendre-Clebsch necessary conditions for singular extremals in optimal control *** first is convenient to test the optimality of a singular *** second compact form is very important but it seems to be unknown in the *** it is satisfied in the strengthened manner it provides sufficient conditions for the control variable to be computed in terms of the state and costate *** illustrate the usefulness of these compact forms of the Goh-Legendre-Clebsch conditions by a detailed analysis of a simple *** extremals can be very important subarcs of optimal trajectories of rockets and aircraft in the atmosphere and in many other applications of optimal control in fisheries,economics and theoretical physics.

关键词： Optimal Control Theory Singular Control Optimal Rocket Trajectories Goh-Legendre-Clebsch Condtions Optimal Aircraft Trajectories

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Earthquake Engineering and Engineering Vibration 2002年第1期1卷 86-93页

作者： Chin-Hsiung Loh Wen-I Liao Juin-Fu Chai Department of Civil Engineering Taiwan Universityand Center for Research on Earthquake EngineeringChinese Taipei Professor Center for research on Earthquake Engineering Chinese Taipei Associate Research Fellow

The objective of this paper is to describe the lessons learned and actions that have been taken related to the seismic design of bridge structures after the Chi-Chi,Taiwan *** variable near-fault ground motion data was collected from the rupture of Chelungpu fault during the Chi-Chi earthquake,allowing the seismic response of bridge structures subjected to these near-fault ground motions to be carefully *** study the near-fault ground motion effect on bridge seismic design codes,a two-level seismic design of bridge structures was developed and *** design code reflects the near-fault factors in the seismic design ***,a risk assessment methodology,based on bridge vulnerability,is also developed to assist in decisions for reducing seismic risk due to failure of bridges.

关键词： Chi-Chi earthquake near-fault bridge seismic design risk assessment