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UHAS-MIDA Software Package: Mass Isotopomer Distribution Analysis-Applying the Inverse Matrix for the Determination of Stable Isotopes of Chromium Distribution during Red Blood Cell Labelling
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作者 Daniel A. Abaye Emmanuel B. Odoom +3 位作者 Ernest Y. Boateng Irene A. Agbo John-Bosco Diekuu Samuel Agana 《Journal of Data Analysis and Information Processing》 2022年第2期142-154,共13页
Clinical assessment of fluid volume status in children during malaria can be taxing and often inaccurate. During malaria, changes in fluid volume are rather multifarious and estimating this parameter, especially in si... Clinical assessment of fluid volume status in children during malaria can be taxing and often inaccurate. During malaria, changes in fluid volume are rather multifarious and estimating this parameter, especially in sick children is very challenging for clinicians who frequently rely on indices such as long capillary refill times, tachycardia, central venous pressure and decreased urine volume as guides. Here, we present the UHAS-MIDA, an open-source software tool that calculates the red blood cell (RBC) concentration and blood volume during malaria in children determined using a stable isotope of chromium (<sup>53</sup>Cr as the label) by gas chromatography-mass spectrometry in selective ion monitoring (GC/MS-SIM) analysis. A key component involves the determination of the compositions of the most abundant naturally occurring isotopes of Cr (<sup>50</sup>Cr, <sup>52</sup>Cr, <sup>53</sup>Cr), and converting the proportions into a 3 × 3 matrix. To estimate unknown proportions of chromium isotopic mixtures from the measured abundances of three ions, an inverse matrix was calculated. The inverse together with several inputs is then used to calculate the corrected MS ion abundances. Thus, we constructed the software tool UHAS- MIDA using HTML, CSS/Bootstrap, JavaScript, and PHP scripting languages. The tool enables the user to efficiently determine RBC concentration and fluid volume. The source code, binary packages and associated materials for UHAS-MIDA are freely available at https://github.com/bentil078/Abaye-et-al_UHASmida 展开更多
关键词 Mass Isotopomer distribution analysis Inverse Matrix GC/MS Chromium Stable Isotopes Blood Volume Red Blood Cell Mass
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Power distribution analysis for multiple modulation formats in an all-optical sampling wavelength division multiplexing system 被引量:2
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作者 于海 陈宏伟 +1 位作者 陈明华 谢世钟 《Chinese Optics Letters》 SCIE EI CAS CSCD 2013年第10期29-32,共4页
An optimal power distribution analysis for an all-optical sampling orthagonal frequency division multiplexing(OFDM) scheme with multiple modulation formats including diferential phase shift keyed(DPSK), diferential qu... An optimal power distribution analysis for an all-optical sampling orthagonal frequency division multiplexing(OFDM) scheme with multiple modulation formats including diferential phase shift keyed(DPSK), diferential quadrature phase shift keyed(DQPSK), and non-return-to-zero(NRZ) is proposed. The noise tolerances of different modulation formats are analyzed, and the optimal input power ratio between phase and intensity modulation formats for the best overall receiving performance is investigated under unchanged total input power. Moreover, this scheme can seamlessly coexist with the traditional WDM channel. 展开更多
关键词 OFDM DQPSK DPSK Power distribution analysis for multiple modulation formats in an all-optical sampling wavelength division multiplexing system
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Impact Analysis of MPL on a PEFC Cell’s Temperature Distribution with Thin PEM and GDL for Operating at Higher Temperature than Usual 被引量:1
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作者 Akira Nishimura Nozomu Kono +2 位作者 Kyohei Toyoda Yuya Kojima Mohan Lal Kolhe 《Journal of Energy and Power Engineering》 2021年第2期39-51,共13页
According to the New Energy and Industry Technology Development Organization(NEDO)road map 2017 of Japan,polymer electrolyte fuel cell(PEFC)system is required to be operated at 90°C and 100°C for stationary ... According to the New Energy and Industry Technology Development Organization(NEDO)road map 2017 of Japan,polymer electrolyte fuel cell(PEFC)system is required to be operated at 90°C and 100°C for stationary and mobility applications,respectively.However,the general PEFC,which has Nafion membrane is operated within the temperature range between 60°C and 80°C.It is important to understand the temperature distribution in a PEFC cell for analyzing performance on working life span of PEFC.This study focuses on the combination of thin polymer electrolyte membrane(PEM)and thin gas diffusion layer(GDL)to improve power generation performance under relatively higher temperature operation conditions.In addition,this study also focuses on effect of micro porous layer(MPL),which can promote the mass transfer,over temperature distribution.The key aim of this study is to analyze impact of MPL of temperature distribution on the reaction surface(Treact)of a cell of PEFC using thin PEM and GDL with variations of H2 and O2 supply flow rates and their relative humidity(RH)with changing the initial operating temperature(Tini)from 80°C to 100°C.As a result,the distribution of Treact without MPL,for anode and cathode at 80%RH and Tini at 80°C and 90°C,is higher than normal conditions.There is a small difference in temperature distribution among different RH conditions with MPL.The distributions of Treact are relatively flat and almost the same among different RH conditions without MPL at Tini=100°C,while the distributions of Treact with MPL are almost the same among different RH conditions.This study is revealed that more even temperature distribution and higher power generation performance can be obtained in the case without MPL compared to the case with MPL. 展开更多
关键词 PEFC temperature distribution analysis MPL thin PEM and thin GDL higher temperature operation
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Complex Seismic Focus Structure and Earthquake-Triggered Landslide Distribution:Analysis of the 2014 Ludian M_w6.1 Earthquake in Yunnan 被引量:3
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作者 CHEN Xiaoli LIU Chunguo 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第2期733-734,共2页
Objective The 2014 Ludian Mw6.1 earthquake in Yunnan occurred in a mountainous area with complex tectonics and topography, which caused serious damage as well as co-seismic landslides of an unusual large scale. Becau... Objective The 2014 Ludian Mw6.1 earthquake in Yunnan occurred in a mountainous area with complex tectonics and topography, which caused serious damage as well as co-seismic landslides of an unusual large scale. Because the suspected seismogenic faults on the surface, distribution of aftershocks and focal mechanism solutions are not consistent, it remains difficult to determine what is the real causal fault or seismogenic structure for this event. Actually, it may imply the complicity of the seismic source at depth. In addition, the distribution of the co- seismic landslides also exhibits some diffusion that is different from general eases, likely associated with the seismic focus structure. 展开更多
关键词 Complex Seismic Focus Structure and Earthquake-Triggered Landslide distribution:analysis of the 2014 Ludian M_w6.1 Earthquake in Yunnan
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Preliminary analysis of distribution and variation of perennialmonthly mean water masses in the Bohai Sea,the Huanghai Sea and the East China Sea 被引量:6
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作者 Liu Shuxun, Shen Xinqiang, Wang Youqin and Han Shixin 1. East China Sea Fisheries Research Institute, No. 300, Jungong Road, Shanghai 200090, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1992年第4期483-498,共16页
On the basis of perennial monthly mean temperature and salinity data, the classification of monthly water masses at the surface and the bottom in the Bohai Sea, the Huanghai Sea and the East China Sea, has been made b... On the basis of perennial monthly mean temperature and salinity data, the classification of monthly water masses at the surface and the bottom in the Bohai Sea, the Huanghai Sea and the East China Sea, has been made by using the method of fuzzy cluster from the modified characteristic of water masses in the shallow water area. In this paper, the basic features, growth and decline patterns of water masses in relation to fishing grounds in the whole shelves of the Bohai Sea, the Huanghai Sea and the East China Sea are discussed with emphasis. 展开更多
关键词 Preliminary analysis of distribution and variation of perennialmonthly mean water masses in the Bohai Sea the Huanghai Sea and the East China Sea
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Analysis of thermohaline and current distribution characteristics of Zhejiang and Fujian waters in summer 被引量:3
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作者 DU Panjun ZHANG Hui +2 位作者 XIAO Wenjun KANG Xing GUAN Qinle 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2011年第5期71-83,共13页
This paper analyzed the distribution of thermohaline and circulation characteristics of Zhejiang and Fujian waters,based on the cross-sectional thermohaline data and on current data (up to 30 d duration) at fixed-po... This paper analyzed the distribution of thermohaline and circulation characteristics of Zhejiang and Fujian waters,based on the cross-sectional thermohaline data and on current data (up to 30 d duration) at fixed-point moorings,collected in the summer of 2006.We also performed low-pass filtering and spectrum analysis on the mooring submersible buoy data.Based on that analysis,we discussed the characteristics of low frequency currents and time-variations in these waters.The main conclusions are as follows.(1) There is a low salinity pinnate area near the Hangzhou Bay in summer,and outside the low salinity area,an obvious salinity front is present from surface to bottom near 123 E.There is also a temperature front below the surface at a corresponding position.(2) Bottom water of the Taiwan Warm Current comes from the subsurface of Kuroshio.(3) The direction of low frequency current at fixed anchor stations is N-NE or S,which mainly depends on the interaction of control currents in this waters.(4) Significant spectral peaks at all mooring stations are typically semidiurnal and diurnal tides.Semidiurnal tidal waves are the main ones in these waters,and have more energy closer to the shore.(5) Significant energy spectral peaks of middle period (3 to 8 d) of currents are responses to weather frequency.(6) Significant energy spectral peaks of long periods at the surface or bottom are probably responses to seasonal wind or bottom friction,while,the long period peaks of other depths can reflect cyclical changes of interactions between currents.We conclude that the pulsation period of the Taiwan Warm Current in these waters is 10-17 d. 展开更多
关键词 Zhejiang and Fujian waters thermohaline distribution low-frequency current spectrum analysis Taiwan Warm Current Kuroshio subsurface water
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Relationships between femoral strength evaluated by nonlinear finite element analysis and BMD,material distribution and geometric morphology
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作者 He Gong1,Linwei Lv1,Rui Zhang1,Dong Zhu3,Ming Zhang2(1.Department of Engineering Mechanics,Jilin University,Changchun 130025,P.R.China 2.Department of Health Technology and Informatics,The Hong Kong Polytechnic University,Hong Kong,China 3.Department of Orthopedic Surgery,No.1 Hospital,Jilin University,Changchun 130021,China) 《医用生物力学》 EI CAS CSCD 2009年第S1期66-66,共1页
Precisely quantifying the strength of the proximal femur and accurately assessing hip fracture risk would enable those at high risk to be identified so that preventive interventions could be taken.Development of bette... Precisely quantifying the strength of the proximal femur and accurately assessing hip fracture risk would enable those at high risk to be identified so that preventive interventions could be taken.Development of better measures of femoral strength using the clinically 展开更多
关键词 BMD Relationships between femoral strength evaluated by nonlinear finite element analysis and BMD material distribution and geometric morphology FEA
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Distribution and segregation of dissolved elements in pipeline slab 被引量:3
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作者 Jianhua Liu Yanping Bao +3 位作者 Xian Dong Taiquan Li Yi Ren Shuai Zhang 《Journal of University of Science and Technology Beijing》 CSCD 2007年第3期212-218,共7页
The chemical composition in a cross section of a high grade pipeline slab was measured point by point (in a scale of 1 μm) using original position statistic distribution analysis (OPA). The result indicated that ... The chemical composition in a cross section of a high grade pipeline slab was measured point by point (in a scale of 1 μm) using original position statistic distribution analysis (OPA). The result indicated that negative segregation strips of Si, Mn, Mo, Ni, Cr, Nb, Cu, Ti, and V exist in the two sides 24 mm away from the central line, with a width of 8-12 mm, Negative segregation inside the central line is more severe than that outside the central line, and the highest positive segregation of the elements appears closely by the inner sides of the negative segregation strips. No obvious negative segregation strip of S and P is found. Segregation of the elements in the central area is higher than that in the outer and inner arc areas. The segregation of C, Ti, S, and P is high and that of Cr, Cu, Si, and Mn is low in the slab. 展开更多
关键词 original position statistic distribution analysis (OPA) SEGREGATION negative segregation PIPELINE
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NEW TECHNOLOGY FOR FAULT DIAGNOSIS BASED ON WAVELET DENOISING AND MODIFIED EXPONENTIAL TIME-FREQUENCY DISTRIBUTION 被引量:13
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作者 Wang Xinqing,Wang Yaohua,Qian Shuhua,Chen Liuhai (Engineering College of PLA University of Science and Technology) Xu Yanshen,Zhao Xiangsong (Tianjin University) 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2001年第3期262-265,共4页
Fast wavelet multi-resolution analysis (wavelet MRA) provides a effective tool for analyzing and canceling disturbing components in original signal. Because of its exponential frequency axis, this method isn't s... Fast wavelet multi-resolution analysis (wavelet MRA) provides a effective tool for analyzing and canceling disturbing components in original signal. Because of its exponential frequency axis, this method isn't suitable for extracting harmonic components. The modified exponential time-frequency distribution ( MED) overcomes the problems of Wigner distribution( WD) ,can suppress cross-terms and cancel noise further more. MED provides high resolution in both time and frequency domains, so it can make out weak period impulse components fmm signal with mighty harmonic components. According to the 'time' behavior, together with 'frequency' behavior in one figure,the essential structure of a signal is revealed clearly. According to the analysis of algorithm and fault diagnosis example, the joint of wavelet MRA and MED is a powerful tool for fault diagnosis. 展开更多
关键词 Wavelet multi-resolution analysis Denoising Modified exponential distribution Fault diagnosis
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BAYESIAN DEMONSTRATION TEST METHOD WITH MIXED BETA DISTRIBUTION 被引量:5
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作者 MING Zhimao TAO Junyong +1 位作者 CHEN Xun ZHANG Yun'an 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2008年第3期116-119,共4页
A complex mechatronics system Bayesian plan of demonstration test is studied based on the mixed beta distribution. During product design and improvement various information is appropriately considered by introducing i... A complex mechatronics system Bayesian plan of demonstration test is studied based on the mixed beta distribution. During product design and improvement various information is appropriately considered by introducing inheritance factor, moreover, the inheritance factor is thought as a random variable, and the Bayesian decision of the qualification test plan is obtained, and the correctness of a Bayesian model presented is verified. The results show that the quantity of the test is too conservative according to classical methods under small binomial samples. Although traditional Bayesian analysis can consider test information of related or similar products, it ignores differences between such products. The method has solved the above problem, furthermore, considering the requirement in many practical projects, the differences among this method, the classical method and Bayesian with beta distribution are compared according to the plan of reliability acceptance test. 展开更多
关键词 Reliability qualification test Inheritance factor Bayesian analysis Binomial distribution Maximum posterior risk
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THEORETICAL INVESTIGATION ON STATE OF LOAD DISTRIBUTION AMONG CONTACT BEARINGS OF DOUBLE CIRCULAR ARC HELICAL GEARS 被引量:3
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作者 Wu Baolin (Gear Research Institute, Taiyuan University of Technology) 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2000年第2期108-113,共6页
A dynamic analysis approcach to investigate the state of load distribution among contact bearings of double circular are belical gears is proposed and a computer program is developed for calculating the factor of iced... A dynamic analysis approcach to investigate the state of load distribution among contact bearings of double circular are belical gears is proposed and a computer program is developed for calculating the factor of iced distribution based on the theory of W-N gears. The changing situations of load distribution among contact bearings of the gears influenced by main issues are analyzed by a series of parametric studies. 展开更多
关键词 Double circular are belical gears State of load distribution Factor of load distribution Dynamic analysis
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Wave Energy Estimation by Using A Statistical Analysis and Wave Buoy Data near the Southern Caspian Sea 被引量:2
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作者 A.R.Zamani M.A.Badri 《China Ocean Engineering》 SCIE EI CSCD 2015年第2期275-286,共12页
Statistical analysis was done on simultaneous wave and wind using data recorded by discus-shape wave buoy. The area is located in the southern Caspian Sea near the Anzali Port. Recorded wave data were obtained through... Statistical analysis was done on simultaneous wave and wind using data recorded by discus-shape wave buoy. The area is located in the southern Caspian Sea near the Anzali Port. Recorded wave data were obtained through directional spectrum wave analysis. Recorded wind direction and wind speed were obtained through the related time series as well. For 12-month measurements(May 25 2007-2008), statistical calculations were done to specify the value of nonlinear auto-correlation of wave and wind using the probability distribution function of wave characteristics and statistical analysis in various time periods. The paper also presents and analyzes the amount of wave energy for the area mentioned on the basis of available database. Analyses showed a suitable comparison between the amounts of wave energy in different seasons. As a result, the best period for the largest amount of wave energy was known. Results showed that in the research period, the mean wave and wind auto correlation were about three hours. Among the probability distribution functions, i.e Weibull, Normal, Lognormal and Rayleigh, "Weibull" had the best consistency with experimental distribution function shown in different diagrams for each season. Results also showed that the mean wave energy in the research period was about 49.88 k W/m and the maximum density of wave energy was found in February and March, 2010. 展开更多
关键词 probability distribution function nonlinear auto-correlation wave energy statistical analysis Anzali Port
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INFLUENCE OF THREAD PITCH ON LOAD DISTRIBUTION ON THREADED END OF PRESSURE CYLINDER
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作者 Kobayashi, Mitsuo Hongo, Kaoru Tanaka, Michihiko 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 1998年第4期36-41,共6页
One of the design methods for closing the end of a pressure cylinder is to screw down a screw plug on the threaded end of the cylinder. In this case, there is the problem of stress concentration in the threaded end of... One of the design methods for closing the end of a pressure cylinder is to screw down a screw plug on the threaded end of the cylinder. In this case, there is the problem of stress concentration in the threaded end of the pressure cylinder. To solve the problem, it is necessary to know accurately the load distribution on the threaded end of the cylinder. To find the load distribution on the threaded end of the pressure cylinder engaged with the screw plug, the following experiments are carried out. Applying the tensile load between the screw plug and the pressure cylinder and regarding the situation above as equivalent to the situation in which the internal pressure is applied, the load distribution is measured with the strain gauge. The influence of thread pitch on the load distribution on the threaded end of the cylinder is presented and an optimum pitch for design is discussed. 展开更多
关键词 Pressure cylinder Screw plug Threaded end Load distribution Experiment analysis
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Study on original position statistic quantitative method for the content of Al in inclusions from steels
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作者 LI Dongling,LI Meiling,JIA Yunhai and WANG Haizhou Central Iron & Steel Research Institute,Beijng 100081,China 《Baosteel Technical Research》 CAS 2010年第S1期120-,共1页
The inclusions of Al in steels have great influence on the properties and the quality of steels.But there are some difficulties on the content determination of Al inclusions with accuracy and rapidity.Conventional qua... The inclusions of Al in steels have great influence on the properties and the quality of steels.But there are some difficulties on the content determination of Al inclusions with accuracy and rapidity.Conventional quantity analysis of stable inclusions is electrolysis method with the disadvantages of long analytical period,trivial operation and a little loss of some fine and instable oxides.The content of insoluble aluminum can be obtained by the subtraction between the content of total Al and acid soluble Al determined by chemical methods with the disadvantage of complicate procedure.Original position statistic distribution analysis(OPA) can be used for the determination of inclusions by collecting and discriminating the signals produced by single spark discharge in the way of no pre-sparking,scanning and emitting continuously.In this study the element of Al in some spectrum certified reference materials of carbon and medium or low-alloyed steels was analyzed by original opposition statistic distribution technique.Two quantitative mathematical models used by original position distribution analysis technology for the analysis of the content of Al inclusions have been investigated and been applied to the analysis of the content of Al inclusions in many kinds of spectrum certified reference materials and some medium and low-alloyed steel samples.The scope of application of the models and their limited conditions were discussed.It was found that the results calculated by OPA had great difference with the value by chemical method for some samples with the total content of Al above 0.2%.The reason is that some intensity of abnormal sparks have gone beyond the range of the largest intensity that can be determined by the instrument so that there is a certain deviation on the identification of abnormal sparks and the calculation of threshold value.It was found that the size distribution of Al inclusions had a great influence on the application of the two models.For most of certified reference materials for spectrum analysis and real steel samples the results of the content of Al in inclusions calculated by model 1 was satisfied and had good coincidence with the value of insoluble Al by chemical method. But for the samples with so many large inclusions of Al existed,the influence of intensity should be considered because the signal increase did not vary in the form of simple function.So model 2 was more suitable for the content calculation of Al in inclusions in this case.In order to choose suitable model to be used it is suggested that the size distribution of inclusions should be determined by OPA before content determination of Al in inclusions. The results of the content of Al inclusions calculated by the selected mathematical model were satisfied and had good coincidence with the value of insoluble Al obtained by the subtraction between the content of total Al and soluble Al determined by chemical methods when the content of total aluminum was below 0.2%. 展开更多
关键词 STEEL aluminum inclusions original position statistic distribution analysis mathematical quantitative model insoluble aluminum
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Case-specificity and Its Implications in Distribution Network Analysis with Increasing Penetration of Photovoltaic Generation 被引量:4
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作者 Kalpesh A.Joshi Naran M.Pindoriya 《CSEE Journal of Power and Energy Systems》 SCIE 2017年第1期101-113,共13页
Distribution system analysis(DSA)currently faces several challenges due to inclusion of distributed energy resources(DERs),which have many characteristics,such as inherent variability,uncertainty,possibility of flexib... Distribution system analysis(DSA)currently faces several challenges due to inclusion of distributed energy resources(DERs),which have many characteristics,such as inherent variability,uncertainty,possibility of flexible four quadrant converter operations with distributed generation(DG),and the need for efficient operations to improve reliability of the supply system.This article argues for a high degree of case-specificity and discusses its implications in distribution networks with increasing DG penetration.The research is based on the exhaustive yearly simulation analyses of 132 candidate scenarios and investigates the effects of feeder-specific factors,such as geo-electric size and feeder spread,load density,and phase unbalancing.Nineteen(19)feeder variants—with phase-domain detailed modeling of all feeder components,including DGs,are subjected to increasing penetration of photovoltaic generation without altering the type and location of DGs.The objective is to analyze the role of feederspecific factors on feeder response characteristics in terms of annualized operational parameters,such as energy losses,feeder voltage profile,average power factor,and peak demand at a substation node,as well as tap-changer operations of voltage regulating equipment and their interaction with shunt compensation.Recorded annual load profiles—industrial,commercial,and residential—as well as location specific weather data are used to simulate the candidate scenarios based on three IEEE test feeders and one actual spot network in India.Results signify the consideration of feeder-specific factors in the planning exercise of grouping“similar”feeders for formulating the strategies that can improve daily operations of distribution feeders.The demonstrated case-specificity also implies that optimization algorithms for improved operations with DGs will need to be based on an integrated approach that accounts for feeder-specific factors as well as cyclic variability of DERs. 展开更多
关键词 Case-specificity distribution system analysis distributed generation photovoltaic generation time-series power flow analysis unbalanced distribution networks
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Spatiotemporal heterogeneity of phytoplankton diversity and its relation to water environmental factors in the southern waters of Miaodao Archipelago,China 被引量:3
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作者 ZHENG Wei LI Fen +8 位作者 SHI Honghua HUO Yuanzi LI Yan CHI Yuan GUO Zhen WANG Yuanyuan SHEN Chengcheng LIU Jian QIAO Mingyang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第2期46-55,共10页
To study the water quality influenced by the anthropogenic activities and its impact on the phytoplankton diversity in the surface waters of Miaodao Archipelago, the spatiotemporal variations in phytoplankton communit... To study the water quality influenced by the anthropogenic activities and its impact on the phytoplankton diversity in the surface waters of Miaodao Archipelago, the spatiotemporal variations in phytoplankton communities and the environmental properties of the surface waters surrounding the Five Southern Islands of Miaodao Archipelago were investigated, based on seasonal field survey conducted from November 2012 to August 2013. During the survey, a total of 109 phytoplankton species from 3 groups were identified in the southern waters of Miaodao Archipelago, of which 77 were diatoms, 29 were dinoflagellates, and 3 were chrysophytes. Species number was higher in winter(73), moderate in autumn(70), but lower in summer(31) and spring(27). The species richness index in autumn(5.92) and winter(4.28) was higher than that in summer(2.83) and spring(1.41).The Shannon-Wiener diversity index was high in autumn(2.82), followed by winter(1.99) and summer(1.92), and low in spring(0.07). The species evenness index in autumn(0.46) and summer(0.39) was higher than that in winter(0.32) and spring(0.02). On the basis of principal component analysis(PCA) and redundancy analysis(RDA), we found that dissolved inorganic nitrogen(DIN) and chemical oxygen demand(COD) in spring, COD in summer, p H in autumn, and salinity and oil pollutant in winter, respectively, showed the strongest association with the distribution of phytoplankton diversity. The spatial heterogeneity of the southern waters of Miaodao Archipelago was quite obvious, and three zones, i.e., northeastern, southwestern and inter-island water area, were identified by cluster analysis(CA) based on key environmental variables. 展开更多
关键词 Miaodao Archipelago environmental factors spatial distribution phytoplankton statistical analysis
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The analysis of the transient temperature distribution of double-slab Nd:YAG laser medium 被引量:1
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作者 黄燕 孟俊清 +1 位作者 张玲玲 胡企铨 《Chinese Optics Letters》 SCIE EI CAS CSCD 2005年第3期159-162,共4页
A novel double-slab Nd:YAG laser, which uses face-pumped slab medium cooled by liquid with different temperatures on both sides, is proposed. The thermal distortion of wavefront caused by the non-uniform temperature d... A novel double-slab Nd:YAG laser, which uses face-pumped slab medium cooled by liquid with different temperatures on both sides, is proposed. The thermal distortion of wavefront caused by the non-uniform temperature distribution in the laser gain media can be self-compensated. According to the method of operation, the models of the temperature distribution and stress are presented, and the analytic solutions for the model are derived. Furthermore, the numerical simulations with pulse pumping energy of 10 J and repetition frequencies of 500 and 1000 Hz are calculated respectively for Nd:YAG laser medium. The simulation results show that the temperature gradient remains the approximative linearity, and the heat stress is within the extreme range. Then the absorption coefficient is also discussed. The result indicates that the doping concentration cannot be too large for the high repetition frequency laser. It has been proved that the high repetition frequency, high laser beam quality, and high average outp 展开更多
关键词 YAG The analysis of the transient temperature distribution of double-slab Nd ND
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Empirical Analysis of Wealth Distribution Disparity of Chinese Residents and Its Changes
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作者 Shi Li Zhong Wei Sai Ding 《China & World Economy》 SCIE 2005年第6期40-51,共12页
This article describes and analyses the disparity in wealth distribution of Chinese residents, on the basis of results of sample surveys from 1995 to 2002. It finds an obvious worsening trend, mainly due to the rapid ... This article describes and analyses the disparity in wealth distribution of Chinese residents, on the basis of results of sample surveys from 1995 to 2002. It finds an obvious worsening trend, mainly due to the rapid widening of the urban-rural gap. The process of privatisation of urban housing has led to a narrowing of the wealth gap between urban residents, and has also led to a widening of the wealth gap between urban and rural residents, as well as the national wealth gap. As incomes from land decline, the relative weight of land value in rural residents' overall wealth possession has been decreasing and the role of land in narrowing the nation's urban-rural gap has been weakened. In addition, this article also holds that the financial assets of residents wiU play a greater role in enlarging the overall wealth distribution disparity. 展开更多
关键词 wealth distribution urban-rural gap decomposition empirical analysis
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Multifractal modeling of the production of concentrated sugar syrup crystal
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作者 闭胜 高剑波 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第7期158-163,共6页
High quality, concentrated sugar syrup crystal is produced in a critical step in cane sugar production: the clarification process. It is characterized by two variables: the color of the produced sugar and its clarit... High quality, concentrated sugar syrup crystal is produced in a critical step in cane sugar production: the clarification process. It is characterized by two variables: the color of the produced sugar and its clarity degree. We show that the temporal variations of these variables follow power-law distributions and can be well modeled by multiplicative cascade multifractal processes. These interesting properties suggest that the degradation in color and clarity degree has a systemwide cause. In particular, the cascade multifractal model suggests that the degradation in color and clarity degree can be equivalently accounted for by the initial "impurities" in the sugarcane. Hence, more effective cleaning of the sugarcane before the clarification stage may lead to substantial improvement in the effect of clarification. 展开更多
关键词 time series analysis non-poisson process power-law distribution multiplicative cascade multifractal processes
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Analysis of China's Urban Income Distribution
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《World Economy & China》 SCIE 2001年第4期28-32,共5页
关键词 analysis of China’s Urban Income distribution
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