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The Experimental Measurement of the Relative Biological Effectiveness of Carbon Ions with Different Qualities
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作者 于菊芳 李文建 《Plasma Science and Technology》 SCIE EI CAS CSCD 2008年第3期387-390,共4页
The relative biological effectiveness (RBE) of carbon ions with linear energy transfer (LET) of 172 keV/μm and 13.7 keV/μm were determined in this study. The clonogenic survival and premature terminal differenti... The relative biological effectiveness (RBE) of carbon ions with linear energy transfer (LET) of 172 keV/μm and 13.7 keV/μm were determined in this study. The clonogenic survival and premature terminal differentiation were measured on normal human fibroblasts AG01522C and NHDF after exposure of the cells to 250 kV X-rays and carbon ions with different qualities. RBE was determined for these two biological end points. The results showed that the measured RBE10 with a survival fraction of 10% was 3.2 for LET 172 keV/μm, and 1.33 for LET 13.7 keV/μm carbon ions. RBE for a doubling of post-mitotic fibroblasts (PMF) in the population was 2.8 for LET 172 keV/μm, and 1 for LET 13.7 keV/μm carbon ions. For the carbon ion therapy, a high RBE value on the Bragg peak results in a high biological dose on the tumour. The tumour cells can be killed effectively. At the same time, the dose on healthy tissue would be reduced accordingly. This will lighten the late effect such as fibrosis on normal tissue. 展开更多
关键词 carbon ions relative biological effectiveness measurement
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Statistical Methods for Effectiveness Estimation of Municipal Institutions
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作者 E. Yu. Chemezova K. A. Zaykov 《Open Journal of Statistics》 2014年第9期797-801,共5页
Municipal institutions operate in all sectors of the urban economy, creating jobs, providing services, and creating income for their own development and the municipal budget. Market environment and innovative vector o... Municipal institutions operate in all sectors of the urban economy, creating jobs, providing services, and creating income for their own development and the municipal budget. Market environment and innovative vector of megapolis development include the establishment municipal institutions and improve the forms of their activities. One of the strategic objectives for the government is to increase the effectiveness of municipal institutions. Problems integrated estimation of these institutions are under intense scrutiny of statistical science in management decisions. This paper discussed the problems of effectiveness estimation of municipal institutions and proposed a new approach to solving this task. 展开更多
关键词 MUNICIPAL institutions SOCIO-ECONOMIC Systems effectiveness ESTIMATION TYPOLOGY Typological Grouping Multidimensional Average Multiplicative Effect Balanced SCORECARD
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Finesse measurement for high-power optical enhancement cavity
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作者 陆心怡 柳兴 +3 位作者 田其立 王焕 汪嘉俊 颜立新 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期414-421,共8页
Finesse is a critical parameter for describing the characteristics of an optical enhancement cavity(OEC). This paper first presents a review of finesse measurement techniques, including a comparative analysis of the a... Finesse is a critical parameter for describing the characteristics of an optical enhancement cavity(OEC). This paper first presents a review of finesse measurement techniques, including a comparative analysis of the advantages, disadvantages, and potential limitations of several main methods from both theoretical and practical perspectives. A variant of the existing method called the free spectral range(FSR) modulation method is proposed and compared with three other finesse measurement methods, i.e., the fast-switching cavity ring-down(CRD) method, the rapidly swept-frequency(SF) CRD method, and the ringing effect method. A high-power OEC platform with a high finesse of approximately 16000 is built and measured with the four methods. The performance of these methods is compared, and the results show that the FSR modulation method and the fast-switching CRD method are more suitable and accurate than the other two methods for high-finesse OEC measurements. The CRD method and the ringing effect method can be implemented in open loop using simple equipment and are easy to perform. Additionally, recommendations for selecting finesse measurement methods under different conditions are proposed, which benefit the development of OEC and its applications. 展开更多
关键词 optical enhancement cavity finesse measurement cavity ring-down ringing effect
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Non-Kramers doublet ground state in a quaternary cubic compound PrRu_(2)In_(2)Zn_(18) investigated by ultrasonic measurements
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作者 张化远 Kazuhei Wakiya +2 位作者 Mitsuteru Nakamura Masahito Yoshizawa Yoshiki Nakanish 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期405-411,共7页
We performed ultrasonic measurements on a quaternary cubic compound PrRu_(2)In_(2)Zn_(18) to explore the ground state properties derived from non-Kramers Γ_(3) doublet of Pr^(3+).PrRu_(2)In_(2)Zn_(18) is a quaternary... We performed ultrasonic measurements on a quaternary cubic compound PrRu_(2)In_(2)Zn_(18) to explore the ground state properties derived from non-Kramers Γ_(3) doublet of Pr^(3+).PrRu_(2)In_(2)Zn_(18) is a quaternary derivative of the ternary compound PrRu_(2)Zn_(20) that exhibits a structural phase transition at T_S=138 K.In PrRu_(2)In_(2)Zn_(18),the Zn atoms at the 16c site in PrRu_(2)Zn_(20) are selectively replaced by In atoms.A monotonic increase was observed in the temperature dependence of elastic constants C_L=(C_(11)+2C_(12)+4C_(44))/3 and C_(T)=(C_(11)-C_(12)+C_(44))/3 in the temperature range around T_(S) to which an elastic softening was observed in(C_(11)-C_(12))/2 for PrRu_(2)Zn_(20).The disappearance of the softening indicates that the structural transition in PrRu_(2)Zn_(20) is suppressed by the substitution of Zn ions by In ones with a larger ionic radius.Alternatively,the C_(T) of PrRu_(2)In_(2)Zn_(18) exhibits a precursor Curie-type elastic softening toward low temperatures being responsible for the non-Kramers Γ_(3) ground state.We discuss the ground state and the evolution of the elastic properties of the different single-crystal samples of PrRu_(2)In_(2)Zn_(18) grown under different conditions. 展开更多
关键词 ultrasonic measurements non-Kramers doublet structural phase transition crystalline electric field effect
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Research on the Impact of China’s Foreign Trade Technology Spillover on Green Total Factor Productivity of Countries Along the“Belt and Road”:Based on the Institutional Quality Threshold Effect
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作者 Li Chai Longnan Ma Lingwei Meng 《Proceedings of Business and Economic Studies》 2024年第2期120-125,共6页
China’s growing trade with countries along the“Belt and Road”Initiative is accompanied by a focus on green development.Based on the panel data from 2007 to 2018,this paper establishes a threshold regression model t... China’s growing trade with countries along the“Belt and Road”Initiative is accompanied by a focus on green development.Based on the panel data from 2007 to 2018,this paper establishes a threshold regression model to empirically analyze the institutional quality threshold effect of China’s foreign trade technology spillover on the GTFP of countries along the“Belt and Road.”The results show that China’s foreign trade technology spillover has a significant institutional quality double threshold effect on the green total factor productivity of the countries along the“Belt and Road.”As the institutional quality of the countries along the“Belt and Road”crosses a specific threshold value,the impact of China’s foreign trade technology spillover on the green total factor productivity of the countries along the“Belt and Road”has a significant positive promoting effect,and corresponding suggestions are put forward. 展开更多
关键词 Technology spillover Green total factor productivity institutional quality Threshold effect
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Poverty Reduction in China: Experiences and Measurement of Effects
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作者 Zhan Wang 《China Economist》 2024年第1期103-126,共24页
This study employs the generalized method of moments(GMM)and panel vector autoregression(PVAR)models for a multi-factor quantitative dissection of China’s poverty reduction process across multiple stages,using provin... This study employs the generalized method of moments(GMM)and panel vector autoregression(PVAR)models for a multi-factor quantitative dissection of China’s poverty reduction process across multiple stages,using provincial panel data from 2000 to 2019.According to our research,economic growth and social development are the key drivers of poverty reduction in China,but the trickle-down effect of economic growth is diminishing and marketization is having a lesser pro-poor effect.Public expenditure has failed to provide social protection and income redistribution benefits due to issues such as targeting error and elite capture.Increasing the efficiency of the poverty reduction system calls for adaptive adjustments.Finally,this study highlights China’s poverty reduction experiences and analyzes current challenges,which serve as inspiration for consolidating poverty-reduction achievements,combating relative poverty,and attaining countryside vitalization. 展开更多
关键词 Poverty reduction governance measurement of effects countryside vitalization common prosperity
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Speed Measurement Feasibility by Eddy Current Effect in the High-Speed MFL Testing
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作者 Zhaoting Liu Jianbo Wu +4 位作者 Sha He Xin Rao Shiqiang Wang Shen Wang Wei Wei 《Structural Durability & Health Monitoring》 EI 2023年第4期299-314,共16页
It is known that eddy current effect has a great influence on magnetic flux leakage testing(MFL).Usually,contacttype encoder wheels are used to measure MFL testing speed to evaluate the effect and further compensate t... It is known that eddy current effect has a great influence on magnetic flux leakage testing(MFL).Usually,contacttype encoder wheels are used to measure MFL testing speed to evaluate the effect and further compensate testing signals.This speed measurement method is complicated,and inevitable abrasion and occasional slippage will reduce the measurement accuracy.In order to solve this problem,based on eddy current effect due to the relative movement,a speed measurement method is proposed,which is contactless and simple.In the high-speed MFL testing,eddy current induced in the specimen will cause an obvious modification to the applied field.This modified field,which is measured by Hall sensor,can be utilized to reflect the moving speed.Firstly,the measurement principle is illustrated based on Faraday’s law.Then,dynamic finite element simulations are conducted to investigate the modified magnetic field distribution.Finally,laboratory experiments are performed to validate the feasibility of the proposed method.The results show that Bmz(r1)and Bmx(r2)have a linear relation with moving speed,which could be used as an alternative measurement parameter. 展开更多
关键词 Magnetic flux leakage testing(MFL) speed measurement eddy current effect modified magnetic field
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Circular economy: from an institutional perspective 被引量:1
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作者 Lu Jingchao 《Ecological Economy》 2007年第2期114-121,共8页
Circular economy (CE) has been put fonvard as an important environmental and resource strategy in China.Aiming at the high utilization rate of resources and reduction of pollutants,CE means to realize a shift of fun... Circular economy (CE) has been put fonvard as an important environmental and resource strategy in China.Aiming at the high utilization rate of resources and reduction of pollutants,CE means to realize a shift of fundamental paradigm.With the mode of production and consumption from linear to recycling model,the promotion requires transdisciplinary researches which integrate technological,ecological,social-cultural and other sciences.The present study focuses on the implementation of circular economy from an institutional perspective.Institution acts as a crucial factor by providing incentives for technical innovation,leading investment orientation and determining policy effectiveness,etc.This paper mainly discusses about: firstly,the feature of institution,institutional changes and institutional innovation is articulated,together with eco-industrial park strategy,extended producer's responsibility and dematerialization principle as innovative institutional arrangements; secondly,as policy plays great role on institutional changing process,the mechanism of policy implementation is needed to be related; as a result,coevolution of institutions and policies is thus presented; at last,a pilot attempt is made to find out some operational avenues in accomplishment of CE through both theoretical and practical methodology,special resolutions are put forward after some projecting difficulties and dilemmas in China are described. 展开更多
关键词 Circular economy institutional innovation Policy effectiveness Coevolution
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A multi-paradigm decision modeling framework for combat system effectiveness measurement based on domain-specific modeling 被引量:3
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作者 Xiao-bo LI Yong-lin LEI +2 位作者 Hans VANGHELUWE Wei-ping WANG Qun LI 《Journal of Zhejiang University-Science C(Computers and Electronics)》 SCIE EI 2013年第5期311-331,共21页
Decision modeling is an essential part of the combat system effectiveness simulation (CoSES), which needs to cope with the cognitive quality, diversity, flexibility, and higher abstraction of decision making. In this ... Decision modeling is an essential part of the combat system effectiveness simulation (CoSES), which needs to cope with the cognitive quality, diversity, flexibility, and higher abstraction of decision making. In this paper, a multi-paradigm decision modeling framework is proposed to support decision modeling at three levels of abstraction based on domain-specific modeling (DSM). This framework designs a domain-specific modeling language (DSML) for decision modeling to raise the abstraction level of modeling, transforms the domain-specific models to formalism-based models to enable formal analysis and early verification and validation, and implements the semantics of the DSML based on a Python scripts framework which incorporates the decision model into the whole simulation system. The case study shows that the proposed approach incorporates domain expertise and facilitates domain modeler's participation in CoSES to formulate the problem using DSML in the problem domain, and enables formal analysis and automatic implementation of the decision model in the solution domain. 展开更多
关键词 Multi-paradigm modeling (MPM) Decision modeling Domain-specific modeling (DSM) effectiveness measurement Model transformation
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Strain Effect of Manganin Transverse Piezoresistive Gauge and Measurement of Dynamic Transverse Stresses 被引量:1
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作者 段卓平 欧卓成 +1 位作者 蔡绍佳 黄风雷 《Journal of Beijing Institute of Technology》 EI CAS 2010年第3期253-258,共6页
Manganin piezoresistive gauges have been extensively used in dynamic stress measurement for decades.It is noted,however,that when used to measure transverse stresses,considerable strain effect is caused as the consequ... Manganin piezoresistive gauges have been extensively used in dynamic stress measurement for decades.It is noted,however,that when used to measure transverse stresses,considerable strain effect is caused as the consequence of change of electrical resistance resulted from bending of wires in the longitudinal-strain-experiencing sensing element of the gauge,a phenomenon discussed in this paper theoretically as well as experimentally.This effect yields unwanted signals to blend with output piezoresistive signals and is not negligible,hence decreases measurement accuracy sizably if not properly handled.To overcome this drawback,a new type of manganin transverse piezoresistive gauge has been developed by authors of this paper,which can reduce the resistance increment to acceptable low level so as to effectively bring the adverse effect under control. 展开更多
关键词 engineering mechanics transverse stress dynamic measurement manganin piezoresistive stress gauge strain effect
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Blasting cumulative damage effects of underground engineering rock mass based on sonic wave measurement 被引量:5
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作者 闫长斌 《Journal of Central South University of Technology》 EI 2007年第2期230-235,共6页
The principle of sonic wave measurement was introduced, and cumulative damage effects of underground engineering rock mass under blasting load were studied by in situ test, using RSM-SY5 intelligent sonic wave apparat... The principle of sonic wave measurement was introduced, and cumulative damage effects of underground engineering rock mass under blasting load were studied by in situ test, using RSM-SY5 intelligent sonic wave apparatus. The blasting test was carried out for ten times at some tunnels of Changba Lead-Zinc Mine. The damage depth of surrounding rock caused by old blasting excavation (0.8-1.2 m) was confirmed. The relation between the cumulative damage degree and blast times was obtained. The results show that the sonic velocity decreases gradually with increasing blast times, hut the damage degree (D) increases. The damage cumulative law is non-linear. The damage degree caused by blast decreases with increasing distance, and damage effects become indistinct. The blasting damage of rock mass is anisotropic. The damage degree of rock mass within charging range is maximal. And the more the charge is, the more severe the damage degree of rock mass is. The test results provide references for researches of mechanical parameters of rock mass and dynamic stability analysis of underground chambers. 展开更多
关键词 sonic wave measurement cumulative damage effects damage degree blasting load surrounding rock of underground engineering RSM-SY5 intelligent sonic wave apparatus
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Volume fraction measurement of oil-water two-phase flow using a coaxial conductivity sensor 被引量:2
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作者 WANG Chao YU Heyang WU Dongyue 《Instrumentation》 2014年第1期49-58,共10页
The accurate measurement of volume fraction of oil-water two-phase flow on line is important in the oil field.This paper presents a new coaxial conductivity sensor for measuring the volume fraction of oil-water two-ph... The accurate measurement of volume fraction of oil-water two-phase flow on line is important in the oil field.This paper presents a new coaxial conductivity sensor for measuring the volume fraction of oil-water two-phase flow.This structure may get the more uniform sensitivity field and the vertical installation may get the more axial symmetry of the flow field,which improve the measurement accuracy.In order to minimize the influence of the edge effect,guard electrodes were designed.An anti-edge effect degree Ae was defined to optimize the length of the guard electrode.Different models of effective conductivity of two materials were used in calculating the oil volume fraction of oil-water two-phase flow.The experimental results indicate that Maxwell model is the best model under the condition of oil volume fraction less than 50%and the mean value of the calculation results using Maxwell model and Bruggeman model possesses higher accuracy in the range of oil volume fraction(50%-70%).The experimental results show that the sensor obtains similar measurement performance in both vertical upward and downward flow conditions.The accuracy of the sensor system is 2%when the oil volume fraction less than 50%,and the accuracy is about 5%when the oil volume fraction between 50%and 70%. 展开更多
关键词 two-phase flow coaxial conductivity sensor volume fraction measurement guard electrodes electrode optimization edge effect
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Thermomechanical analysis of long-term global modal and local deformation measurements of the Kishwaukee Bridge using the bootstrap
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作者 George M.Lloyd Ming L.Wang 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2004年第1期107-115,共9页
In this paper we present a comparative analysis of global frequency and local deformation data for a large concrete bridge. The asymptotic probability distributions of the central statistics are presented, and compare... In this paper we present a comparative analysis of global frequency and local deformation data for a large concrete bridge. The asymptotic probability distributions of the central statistics are presented, and compared with empirical bootstrap estimates. Bootstrapped distributions are calculated from reference data obtained during 1999–2000 and used to develop change-point alarm criteria for the structure, using reasonable sensitivity measures developed from FEM simulations and structural analysis. The implications of the frequency data are discussed in conjunction with the strain and displacement measurements in order to discern if the load carrying capacity of the bridge has been affected. The critical need for more advanced temperature compensation models for large structures continually in thermal disequilibrium is discussed. 展开更多
关键词 thermomechanical effects bootstrap methods local & global monitoring long term measurement concrete bridge
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Strong-field response time and its implications on attosecond measurement
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作者 Chao Chen Jiayin Che +3 位作者 Xuejiao Xie Shang Wang Guoguo Xin Yanjun Chen 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第3期16-23,共8页
To measure and control the electron motion in atoms and molecules by the strong laser field on the attosecond time scale is one of the research frontiers of atomic and molecular photophysics. It involves many new phen... To measure and control the electron motion in atoms and molecules by the strong laser field on the attosecond time scale is one of the research frontiers of atomic and molecular photophysics. It involves many new phenomena and processes and raises a series of questions of concepts, theories, and methods. Recent studies show that the Coulomb potential can cause the ionization time lag(about 100 attoseconds) between instants of the field maximum and the ionization-rate maximum. This lag can be understood as the response time of the electronic wave function to the strong-field-induced ionization event. It has a profound influence on the subsequent ultrafast dynamics of the ionized electron and can significantly change the time–frequency properties of electron trajectory(an important theoretical tool for attosecond measurement). Here, the research progress of response time and its implications on attosecond measurement are briefly introduced. 展开更多
关键词 response time strong-field ionization Coulomb effect attosecond measurement
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ANALYSIS OF THE EFFECT OF THE TRUNCATED SCAN PLANE IN TIME-DOMAIN NEAR-FIELD MEASUREMENTS
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作者 Hu Hongfei Gao Xue Fu Demin(National Key Lab. of Antennas and Microwave Technology, Xidian University, Xi’an 710071) 《Journal of Electronics(China)》 2002年第1期89-93,共5页
The thought and formulation for near-field far-field transformation based on the direct time-domain computation scheme are given. The effect of the truncated scan plane is investigated by simulating time-domain measur... The thought and formulation for near-field far-field transformation based on the direct time-domain computation scheme are given. The effect of the truncated scan plane is investigated by simulating time-domain measurement of an open-ended waveguide antenna, and a simple and effective criterion is derived for removing the truncation errors in the practical time-domain near-field measurements. 展开更多
关键词 Near-field measurement TIME-DOMAIN Truncation effect
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Measuring Effectiveness in E-Commerce Networks
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作者 Christian Koesters 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期296-297,共2页
The revolution of information technology within the p ast twenty years has dramatically changed the picture of our economy. Numerous n ew possibilities of communication have let competition advantages for many compa n... The revolution of information technology within the p ast twenty years has dramatically changed the picture of our economy. Numerous n ew possibilities of communication have let competition advantages for many compa nies and even advantageous macroeconomic consequences emerge on national and international level. Through newly developed information technologies the knowl edge base of market participants improves with a concurrent reduction of the inf ormation obtaining costs. As a result considerable competition advantages develo p for those companies acting in E-commerce networks. These advantages of the la test development lead to macroeconomic effects on national level, if the effecti veness and efficiency increasing possibilities are used more strongly than in ot her countries. Positive international effects arise since the allocation effic iency is increased through intensified competition between different market pa rticipants in various countries. This in turn leads to an increase in wo rldwide prosperity. This causal chain however is not yet realistic to the whole extent, as such an i ncreased transparency of information is not necessarily accepted by all market p articipants. Otherwise a considerable productivity increase would already have o ccurred in industrial countries. Overall the question arises, whether the change s in the competition situation make single enterprises technically more effectiv e, concurrently however deteriorate the efficiency of the entire market through informational asymmetries. To answer these and further questions and to measure the effectiveness and effic iency of various E-commerce networks an interdisciplinary analysis platform is to be developed. With the help of this platform, it should be possible to examin e single and macroeconomic questions, reveal temporal connections and to analyse aspects of business management and national economy, information management, em ployment politics and finance politics. For this, various part-models for the i ndividual knowledge disciplines have to be generated and brought together in the platform. This platform allows various users to make the right decisions (effec tiveness) with the help of the developed models and to competently estimate the effects (efficiency). Currently models of the individual knowledge disciplines (business management, e conomics, computer science) are being developed within the research project EEE. con. This project deals with the question of Supply Chain Management (SCM), E-P rocurement, with the implementation of inter-organisational information systems , as well as various market, competition and organisation models. The department of economics and computer science from Prof. Dr.-Ing. habil. W. Dangelmaier particularly deals with the development of an agent controlled SCM- communication model which is part of the E-commerce analysis platform. Both are described in this paper. Furthermore, a unified modelling language in order to allow a prototypic implementation of the analysis tool and to make the work with other project participants and external participants easier is decided upon wit hin this project. 展开更多
关键词 Measuring effectiveness in E-Commerce Networks
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Heat transfer enhancement in MOSFET mounted on different FR4 substrates by thermal transient measurement
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作者 Norazlina M S Dheepan Chakravarthii M K +2 位作者 Shanmugan S Mutharasu D Shahrom Mahmud 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第9期549-556,共8页
Miniaturization of electronic package leads to high heat density and heat accumulation in electronics device, resulting in short life time and premature failure of the device. Junction temperature and thermal resistan... Miniaturization of electronic package leads to high heat density and heat accumulation in electronics device, resulting in short life time and premature failure of the device. Junction temperature and thermal resistance are the critical parameters that determine the thermal management and reliability in electronics cooling. Metal oxide field effect transistor(MOSFET)is an important semiconductor device for light emitting diode-integrated circuit(LED IC) driver application, and thermal management in MOSFET is a major challenge. In this study, investigations on thermal performance of MOSFET are performed for evaluating the junction temperature and thermal resistance. Suitable modifications in FR4 substrates are proposed by introducing thermal vias and copper layer coating to improve the thermal performance of MOSFET. Experiments are conducted using thermal transient tester(T3ster) at 2.0 A input current and ambient temperature varying from25℃ to 75℃. The thermal parameters are measured for three proposed designs: FR4 with circular thermal vias, FR4 with single strip of copper layer and embedded vias, and FR4 with I-shaped copper layer, and compared with that of plain FR4 substrate. From the experimental results, FR4I-shaped shows promising results by 33.71% reduction in junction temperature and 54.19% reduction in thermal resistance. For elevated temperature, the relative increases in junction temperature and thermal resistance are lower for FR4I-shaped than those for other substrates considered. The introduction of thermal vias and copper layer plays a significant role in thermal performance. 展开更多
关键词 metal oxide field effect transistor(MOSFET) thermal transient measurement heat transfer path FR4
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On the Quantum Zeno Effect and Time Series Related to Quantum Measurements
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作者 Karl-Heinz Fichtner Kei Inoue 《Applied Mathematics》 2013年第10期61-69,共9页
Our main aim is to prove a more general version of the quantum Zeno effect. Then we discuss some examples of the quantum Zeno effect. Furthermore, we discuss a possibility that based on the quantum Zeno effect and cer... Our main aim is to prove a more general version of the quantum Zeno effect. Then we discuss some examples of the quantum Zeno effect. Furthermore, we discuss a possibility that based on the quantum Zeno effect and certain experiments one could check whether, from the statistical point of view, a concrete system behaves like a quantum system. The more general version of quantum Zeno effect can be helpful to prove that the brain acts like in a quantum system. The proof of our main result is based on certain formulas describing probability distributions of time series related to quantum measurements. 展开更多
关键词 Quantum Zeno Effect Quantum measurements Time Series
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Residual lifetime prediction model of nonlinear accelerated degradation data with measurement error 被引量:12
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作者 Zhongyi Cai Yunxiang Chen +1 位作者 Qiang Zhang Huachun Xiang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第5期1028-1038,共11页
For the product degradation process with random effect (RE), measurement error (ME) and nonlinearity in step-stress accelerated degradation test (SSADT), the nonlinear Wiener based degradation model with RE and ME is ... For the product degradation process with random effect (RE), measurement error (ME) and nonlinearity in step-stress accelerated degradation test (SSADT), the nonlinear Wiener based degradation model with RE and ME is built. An analytical approximation to the probability density function (PDF) of the product's lifetime is derived in a closed form. The process and data of SSADT are analyzed to obtain the relation model of the observed data under each accelerated stress. The likelihood function for the population-based observed data is constructed. The population-based model parameters and its random coefficient prior values are estimated. According to the newly observed data of the target product in SSADT, an analytical approximation to the PDF of its residual lifetime (RL) is derived in accordance with its individual degradation characteristics. The parameter updating method based on Bayesian inference is applied to obtain the posterior value of random coefficient of the RL model. A numerical example by simulation is analyzed to verify the accuracy and advantage of the proposed model. 展开更多
关键词 accelerated degradation test residual lifetime (RL) prediction measurement error random effect NONLINEARITY
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Revisiting the methods for gas permeability measurement in tight porous medium 被引量:5
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作者 Diansen Yang Wei Wang +2 位作者 Weizhong Chen Xianjun Tan Lige Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2019年第2期263-276,共14页
Permeability is a key parameter to describe fluid transport properties of porous medium; however, the permeability measurement is extremely difficult for tight porous medium, e.g. fine-grained rock or dense soil. In t... Permeability is a key parameter to describe fluid transport properties of porous medium; however, the permeability measurement is extremely difficult for tight porous medium, e.g. fine-grained rock or dense soil. In this paper, three methods for gas permeability measurement, i.e. steady state method, pulse decay method(PDM) and pressure oscillation method(POM), are first reviewed and then their advantages and drawbacks are discussed. Both analytical and numerical solutions of gas permeability are presented for the tight porous medium. The results show that the analytical method is relatively simple but only valid under certain conditions, whilst the numerical method is more robust and generic, which can take into account several factors such as porosity, saturation, gas leakage, and unconventional boundary conditions. The influence of the effective porosity on the permeability determination is further analyzed using the proposed numerical method. In this study, new pressure data interpretation procedures for PDM and POM are proposed, and the obtained results can serve as a guidance to define a proper method for permeability measurement of the tight porous medium. 展开更多
关键词 Permeability measurement STEADY state METHOD Pulse decay method(PDM) Pressure oscillation method(POM) Effective porosity TIGHT porous medium
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