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An evaluation method of contribution rate based on fuzzy Bayesian networks for equipment system-of-systems architecture
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作者 XU Renjie LIU Xin +2 位作者 CUI Donghao XIE Jian GONG Lin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第3期574-587,共14页
The contribution rate of equipment system-of-systems architecture(ESoSA)is an important index to evaluate the equipment update,development,and architecture optimization.Since the traditional ESoSA contribution rate ev... The contribution rate of equipment system-of-systems architecture(ESoSA)is an important index to evaluate the equipment update,development,and architecture optimization.Since the traditional ESoSA contribution rate evaluation method does not make full use of the fuzzy information and uncertain information in the equipment system-of-systems(ESoS),and the Bayesian network is an effective tool to solve the uncertain information,a new ESoSA contribution rate evaluation method based on the fuzzy Bayesian network(FBN)is proposed.Firstly,based on the operation loop theory,an ESoSA is constructed considering three aspects:reconnaissance equipment,decision equipment,and strike equipment.Next,the fuzzy set theory is introduced to construct the FBN of ESoSA to deal with fuzzy information and uncertain information.Furthermore,the fuzzy importance index of the root node of the FBN is used to calculate the contribution rate of the ESoSA,and the ESoSA contribution rate evaluation model based on the root node fuzzy importance is established.Finally,the feasibility and rationality of this method are validated via an empirical case study of aviation ESoSA.Compared with traditional methods,the evaluation method based on FBN takes various failure states of equipment into consideration,is free of acquiring accurate probability of traditional equipment failure,and models the uncertainty of the relationship between equipment.The proposed method not only supplements and improves the ESoSA contribution rate assessment method,but also broadens the application scope of the Bayesian network. 展开更多
关键词 equipment system-of-systems architecture(ESoSA) contribution rate evaluation fuzzy Bayesian network(FBN) fuzzy set theory
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Weapons system portfolio selection based on the contribution rate evaluation of system of systems 被引量:11
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作者 DOU Yajie ZHOU Zhexuan +1 位作者 ZHAO Danling WEI Yong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第5期905-919,共15页
The weapons system portfolio selection problem arises at the equipment demonstration stage and deals with the military application requirements.Further,the contribution rate of the system is one of the important indic... The weapons system portfolio selection problem arises at the equipment demonstration stage and deals with the military application requirements.Further,the contribution rate of the system is one of the important indicators to evaluate the role of a system,which can facilitate the weapons system portfolio selection.Therefore,combining the system contribution rate with system portfolio selection is the focus of this study.It also focuses on calculating the contribution rates of multiple equipment systems with various types of capabilities.The contribution rate is measured by establishing a hierarchical multi-criteria value model from three dimensions.Based on the value model,the feasible portfolios are developed under certain cost constraints and the optimal weapons system portfolios are obtained by using the classification optimization selection strategy.Finally,an illustrative example is presented to verify the feasibility of the proposed model. 展开更多
关键词 WEAPON SYSTEM SYSTEM of systems (SoS) portfolioselection contribution rate EVALUATION DECISION analysis
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Weapons equipment portfolios selection based on equipment system contribution rates 被引量:5
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作者 LIU Peng LI Jichao +2 位作者 XIA Boyuan ZHAO Danling TAN Yuejin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2021年第3期584-595,共12页
Equipment selection is an essential work in the research and development planning of equipment.The scientific and rational development of weapons equipment portfolios is of considerable significance to the optimizatio... Equipment selection is an essential work in the research and development planning of equipment.The scientific and rational development of weapons equipment portfolios is of considerable significance to the optimization of equipment architecture design,the adequate resources allocation,and the joint combat performance.From the system view,this paper proposes a method of weapons equipment portfolios selection(WEPS)based on the contribution rate of weapon systems,providing a new idea for weapon equipment portfolio selection.Firstly,we analyze the WEPS problem and the concept of the contribution rate under the systems background.Secondly,we propose a combat network modeling method for weapon equipment systems based on the function chain.Thirdly,we propose a WEPS method based on the contribution rate,fully considering the correlation relationships between potential weapons and the old weapon systems by the combat network model,under the limitation of capability demands and budget resources,with the objective to maximally increasing the combat ability of weapon systems.Finally,we make a case study with a specific WEPS problem where the whole calculation processes and results are analyzed and exhibited to verify the feasibility and effectiveness of the proposed method model. 展开更多
关键词 weapons equipment system systems contribution rate equipment portfolio selection combat capability combat network
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Transfer Path Contribution to Floor Vibration of Metro Vehicles Based on Operational Transfer Path Analysis Method 被引量:1
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作者 Laixian Peng Jian Han +2 位作者 Jiaxing Nie Xinbiao Xiao Caiying Mi 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2022年第2期228-238,共11页
Operational transfer path analysis(OTPA)is an advanced vibration and noise transfer path identification and contribution evaluation method.However,the application of OTPA to rail transit vehicles considers only the ex... Operational transfer path analysis(OTPA)is an advanced vibration and noise transfer path identification and contribution evaluation method.However,the application of OTPA to rail transit vehicles considers only the excitation amplitude and ignores the influence of the excitation phase.This study considers the influence of the excitation amplitude and phase,and analyzes the contribution of the secondary suspension path to the floor vibration when the metro vehicle runs at 60 km/h,using an analysis based on the OTPA method.The results show that the vertical direction of the anti-rolling torsion bar area provides the maximum contribution to the floor vibration,with a contribution of 22.1%,followed by the longitudinal vibration of the air spring area,with a contribution of 17.1%.Based on the contribution analysis,a transfer path optimization scheme is proposed,which may provide a reference for the optimization of the transfer path of metro vehicles in the future. 展开更多
关键词 OTPA Secondary suspension contribution analysis transfer path optimization scheme Metro vehicles
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Online Contribution Rate Based Fault Diagnosis for Nonlinear Industrial Pro cesses 被引量:12
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作者 PENG Kai-Xiang ZHANG Kai LI Gang 《自动化学报》 EI CSCD 北大核心 2014年第3期423-430,共8页
在过去的十年,核主管部件分析(KPCA ) 在监视区域的数据驱动的过程相当流行地出现了。庞大的工作被做了显示出它的简洁,可行性,和有效性。然而,核诡计的介绍使直接为差错诊断采用传统的贡献阴谋不可能。在这份报纸,根据重游并且分... 在过去的十年,核主管部件分析(KPCA ) 在监视区域的数据驱动的过程相当流行地出现了。庞大的工作被做了显示出它的简洁,可行性,和有效性。然而,核诡计的介绍使直接为差错诊断采用传统的贡献阴谋不可能。在这份报纸,根据重游并且分析存在, KPCA 相关的诊断来临,新贡献率基于方法被建议它能清楚地解释有缺点的变量。而且,为联机非线性的诊断的一个计划被建立。最后,连续搅动的坦克反应堆(CSTR ) 上的案例研究基准被使用存取新方法论的有效性,在有传统的线性方法的比较也被包含的地方。 展开更多
关键词 故障诊断 非线性 搅拌釜式反应器 工业 费率 核主成分分析 KPCA 数据驱动
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Concept and evaluation method of equipment system of systems contribution rate 被引量:1
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作者 Zhang Tianpeng Liu Tielin Yang Jun 《Journal of Southeast University(English Edition)》 EI CAS 2021年第3期317-324,共8页
To scientifically evaluate the equipment system of systems(SoS)contribution rate,a contribution rate calculation method based on a structural equation model(SEM)is proposed in this paper.The connotation and evaluation... To scientifically evaluate the equipment system of systems(SoS)contribution rate,a contribution rate calculation method based on a structural equation model(SEM)is proposed in this paper.The connotation and evaluation process of the equipment SoS contribution rate were redefined and standardized.To solve the existing problems in the application of the original contribution rate formula,a modified contribution rate calculation formula is proposed.Finally,the contribution rate evaluation index was divided into latent and explicit variables.The measurement and structural equations in the SEM were used to calculate and analyze the latent variables.The simulation results show that the number of defense lines of air defense weapon equipment has a greater impact on the linear configuration than the group configuration.When the number of K-type air defense weapons is sufficient,the two-layer linear configuration should be adopted with 20 air defense weapon systems.When the number of K-type air defense weapons is insufficient,the single-layer group configuration should be adopted with 12 air defense weapon systems. 展开更多
关键词 system of systems(SoS)contribution rate structural equation mode equipment SoS capability assessment evaluation indicator framework
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A Research for Regional Contribution Rate of Internal Source and External Source of PM_(2.5) Based on Set Pair Analysis Method 被引量:1
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作者 Zhou Yejing Zhou Jingxuan Xiao Renbin 《Meteorological and Environmental Research》 CAS 2016年第2期36-40,44,共6页
A problem of the air pollution control in China is getting to know a regional contribution rate of internal and external source of PM2.5. In this paper,Set Pair Analysis( SPA) method is proposed to calculate the con... A problem of the air pollution control in China is getting to know a regional contribution rate of internal and external source of PM2.5. In this paper,Set Pair Analysis( SPA) method is proposed to calculate the contribution rate of PM2.5in Dongguan City. Due to geographic,meteorological factors and the low concentration of air pollutants in Qingxi area,the PM2.5in this place is mainly contributed by the regional transport of air pollutants from other inside areas of Dongguan,and less affected by the outside of Dongguan. So the concentration of PM2.5in Qingxi area can reflect the Dongguan's basic background concentration of PM2.5. On the basis of the basic background concentration,firstly the concentration of each pollutant components is divided into the internal part and the mixed part. Secondly using the source apportionment samples of five monitoring sites in Dongguan we can respectively construct a sample set A and an evaluation set B. Thirdly the SPA is operated onto the mixed part in terms of set B.At last the connection degree between the concentration of each pollutant components and external source and internal source will be calculated,that is the contribution rate. The research reveals that the contribution rate of internal source and external source of PM2.5in Dongguan City is 83%and 17% respectively,which roughly met expectations. This method is simple and effective and it can provide a reference for the government taking reduction measures to control PM2.5pollutants emission. 展开更多
关键词 Set Pair Analysis Connection degree PM2.5 Internal source External source contribution rate
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Influence of O-O formation pathways and charge transfer mediator on lipid bilayer membrane-like photoanodes for water oxidation
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作者 Yingzheng Li Shaoqi Zhan +9 位作者 Zijian Deng Meng Chen Yilong Zhao Chang Liu Ziqi Zhao Hongxia Ning Wenlong Li Fei Li Licheng Sun Fusheng Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期526-537,I0013,共13页
Inspired by the function of crucial components in photosystemⅡ(PSⅡ),electrochemical and dyesensitized photoelectrochemical(DSPEC)water oxidation devices were constructed by the selfassembly of well-designed amphipat... Inspired by the function of crucial components in photosystemⅡ(PSⅡ),electrochemical and dyesensitized photoelectrochemical(DSPEC)water oxidation devices were constructed by the selfassembly of well-designed amphipathic Ru(bda)-based catalysts(bda=2,2'-bipyrdine-6,6'-dicarbonoxyl acid)and aliphatic chain decorated electrode surfaces,forming lipid bilayer membrane(LBM)-like structures.The Ru(bda)catalysts on electrode-supported LBM films demonstrated remarkable water oxidation performance with different O-O formation mechanisms.However,compared to the slow charge transfer process,the O-O formation pathways did not determine the PEC water oxidation efficiency of the dyesensitized photoanodes,and the different reaction rates for similar catalysts with different catalytic paths did not determine the PEC performance of the DSPECs.Instead,charge transfer plays a decisive role in the PEC water oxidation rate.When an indolo[3,2-b]carbazole derivative was introduced between the Ru(bda)catalysts and aliphatic chain-modified photosensitizer in LBM films,serving as a charge transfer mediator for the tyrosine-histidine pair in PSⅡ,the PEC water oxidation performance of the corresponding photoanodes was dramatically enhanced. 展开更多
关键词 Water oxidation rate determine step Dye-sensitized photoelectrochemical cell Charge transfer Artificial photosynthesis
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Contribution Rate of Agricultural Informationization to Growth of Agricultural Economy in Hubei Province and Its Influencing Factors
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作者 Cheng JIA Chunping XIA Yi CAI 《Asian Agricultural Research》 2017年第6期35-39,共5页
Agricultural informationization is the objective demand for transforming the traditional agriculture and promoting the development of agricultural modernization. Using the statistical data of the gross agricultural ou... Agricultural informationization is the objective demand for transforming the traditional agriculture and promoting the development of agricultural modernization. Using the statistical data of the gross agricultural output value of Hubei Province in 2005-2014,based on the C-D production function,it calculated the average contribution rate(2. 48%) of agricultural informationization to the growth of agricultural economy in Hubei Province,indicating that agricultural informationization can promote growth of agricultural economy. This is basically consistent with previous findings. In addition,investment in agricultural informationization and broadband access rate also influenced the growth of agricultural economy in Hubei Province. Therefore,government should further improve the infrastructure of agricultural informationization,strengthen training of farmers’ information skills,establish auxiliary mechanism for achievement feedback of information-based agricultural production,increase the contribution rate of informationization to agricultural operation and management,promote the contribution of informationization to the growth of agricultural economy,so as to increase agricultural income of farmers. 展开更多
关键词 Agricultural informationization Agricultural economy contribution rate Influencing factors Agricultural income
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Forecast model of safety economy contribution rate of China
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作者 刘莉君 施式亮 《Journal of Coal Science & Engineering(China)》 2005年第2期109-111,共3页
It is the rational and exact computation of the safety economy contribution rate that has the far-reaching realistic meaning to the improvement of society cognition to safety and the investment to the nation safety an... It is the rational and exact computation of the safety economy contribution rate that has the far-reaching realistic meaning to the improvement of society cognition to safety and the investment to the nation safety and the national macro-safety decision-makings. The accurate function between safety inputs and outputs was obtained through a founded econometric model. Then the forecasted safety economy contribution rate is 3.01% and the forecasted ratio between safety inputs and outputs is 1:1.81 in China in 2005. And the model accords with the practice of China and the results are sarisfying. 展开更多
关键词 safety economy contribution rate safety input safety output
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Quark Loop Contribution to the Gluon Damping Rate in Hot QCD
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作者 马智磊 朱佳庆 +1 位作者 史超逸 李云德 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第12期22-25,共4页
The contribution of the quark loop to the gluon damping rate at zero momentum is calculated using the effective perturbative expansion technique developed by Braaten and Pisarski. It is shown that in the temperature r... The contribution of the quark loop to the gluon damping rate at zero momentum is calculated using the effective perturbative expansion technique developed by Braaten and Pisarski. It is shown that in the temperature range accessible in the present heavy-ion experiments, the contribution of the quark loop can not be ignored. The numerical results show that the quark loop provides ~n apparent contribution to the gluon damping rate at temperatures of experimental interest. 展开更多
关键词 Quark Loop contribution to the Gluon Damping rate in Hot QCD
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Factors contributing to the oxygen concentration over the Qinghai-Tibetan Plateau and its contribution rate calculation
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作者 Peijun SHI Ying ZHANG +6 位作者 Yanqiang CHEN Wenquan ZHU Xiaokang HU Heyi YANG Lu JIANG Yonggui MA Haiping TANG 《Science China Earth Sciences》 SCIE EI CAS CSCD 2024年第2期497-509,共13页
A decline in atmospheric oxygen concentration is projected in the 21st century given the background of global warming.The Qinghai-Tibetan Plateau is located at a high altitude,and thus,it faces a hypoxia challenge;how... A decline in atmospheric oxygen concentration is projected in the 21st century given the background of global warming.The Qinghai-Tibetan Plateau is located at a high altitude,and thus,it faces a hypoxia challenge;however,knowledge of the factors contributing to its atmospheric oxygen concentration is still lacking.Here,we conducted joint observations of ecosystem oxygen production and carbon sinks and near-surface atmospheric oxygen concentrations on the Qinghai-Tibetan Plateau and meteorological elements at Beijing Fangshan Station.Using seasonal differences and statistical methods,we calculated the relative contribution rates of vegetation to changes in atmospheric oxygen concentration.Our results indicate that solar radiation,atmospheric humidity,and ecosystem oxygen consumption and production have a significant impact on the atmospheric oxygen concentration,and the impact shows temporal and spatial differences.Vegetation significantly impacts the oxygen concentration,with a contribution rate of 16.7%–24.5%,which is underestimated in existing research.Our findings provide important insights into the factors that influence atmospheric oxygen concentration and highlight the contribution of vegetation.To better understand the oxygen dynamics of the Qinghai-Tibetan Plateau,we recommend further field observations of soil respiration and vegetation photosynthesis to clarify the contributions of carbon storage,carbon sinks and other factors to the near-surface atmospheric oxygen concentration. 展开更多
关键词 Qinghai-Tibetan Plateau Oxygen concentration Relative contribution rate Air temperature VEGETATION
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Contribution of Mass Elevation Effect to the Altitudinal Distribution of Global Treelines 被引量:10
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作者 ZHAO Fang ZHANG Bai-ping +4 位作者 ZHANG Shuo QI Wen-wen HE Wen-hui WANG Jing YAO Yong-hui 《Journal of Mountain Science》 SCIE CSCD 2015年第2期289-297,共9页
Alpine treeline, as a prominent ecological boundary between forested mountain slopes and alpine meadow/shrub, is highly complex in altitudinal distribution and sensitive to warming climate. Great efforts have been mad... Alpine treeline, as a prominent ecological boundary between forested mountain slopes and alpine meadow/shrub, is highly complex in altitudinal distribution and sensitive to warming climate. Great efforts have been made to explore their distribution patterns and ecological mechanisms that determine these patterns for more than 100 years, and quite a number of geographical and ecophysiological models have been developed to correlate treeline altitude with latitude or a latitude related temperature. However,on a global scale, all of these models have great difficulties to accurately predict treeline elevation due to the extreme diversity of treeline site conditions.One of the major reasons is that "mass elevation effect"(MEE) has not been quantified globally and related with global treeline elevations although it has been observed and its effect on treeline elevations in the Eurasian continent and Northern Hemisphere recognized. In this study, we collected and compiled a total of 594 treeline sites all over the world from literatures, and explored how MEE affects globaltreeline elevation by developing a ternary linear regression model with intra-mountain base elevation(IMBE, as a proxy of MEE), latitude and continentality as independent variables. The results indicated that IMBE, latitude and continentality together could explain 92% of global treeline elevation variability, and that IMBE contributes the most(52.2%), latitude the second(40%) and continentality the least(7.8%) to the altitudinal distribution of global treelines. In the Northern Hemisphere, the three factors' contributions amount to 50.4%, 45.9% and 3.7% respectively; in the south hemisphere, their contributions are 38.3%, 53%, and 8.7%, respectively. This indicates that MEE, virtually the heating effect of macro-landforms, is actually the most significant factor for the altitudinal distribution of treelines across the globe, and that latitude is relatively more significant for treeline elevation in the Southern Hemisphere probably due to fewer macro-landforms there. 展开更多
关键词 Alpine treeline Intra-mountain base elevation Multiple regression analysis Geographicalfactor Continentality contribution rate
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Variation Diagnosis and Regional Comparison of Different Intensity of Rainfalls and Their Contribution to Total Rainfall in China in the Context of Global Warming 被引量:2
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作者 Feng KONG 《Asian Agricultural Research》 2019年第8期45-55,共11页
Using the data of 545 meteorological stations in 1961-2015,according to the rainfall intensity classification standard issued by the China Meteorological Administration,the rainfall events were divided into six intens... Using the data of 545 meteorological stations in 1961-2015,according to the rainfall intensity classification standard issued by the China Meteorological Administration,the rainfall events were divided into six intensities: light rain,moderate rain,heavy rain,torrential rain,downpour and heavy downpour. The latter three were recorded as total torrential rain,and all the six were recorded as the total rainfall. In terms of the interannual rainfall and rainy days,the whole China was regarded as an object. Firstly,the annual rainfall and rainy day of different intensity of rainfalls of 545 stations in 1961-2015 were calculated. Then,the variation trend of rainfall and rainy days was calculated. Finally,the variation trend of contribution of different intensity of rainfalls and rainy days to total rainfall and rainy days were diagnosed. It obtained the following results.( i) The light rain in China was declining from 1961 to 2015,and the trend values of light rain and rainy days were-411. 44 mm/yr and-136. 99 d/yr,respectively. Heavy rain and total heavy rainfall showed an increasing trend,with rainfall and rainy day trends of 127. 02 and 463. 94 mm/yr and 7. 93 and 4. 24 d/yr,respectively. The total rainfall showed a ' hockey' phenomenon of ' first rise,then decline',and the trend values of rainfall and rainy days were 204. 29 mm/yr and-95. 81 d/yr,respectively. Except the northern region,the rainfall in most parts of China was dominated by increasing trends and was moving towards extremes.( ii) In terms of rainfall contribution rate,the contribution of light rain to total rainfall showed a declining trend,and the trend values of rainfall and rainy day contribution were both-0. 11%/yr. The contribution of other intensity rainfalls to total rainfall showed an increasing trend. The contribution of torrential rain to the total torrential rain showed a declining trend. The contribution trends of rainfall and rainy days were-0. 06% and-0. 03%/yr,respectively. The contribution of downpour and heavy downpour to total torrential rain showed an increasing trend,indicating the intensity of torrential rain in China is increasing. Although the contribution rate of different intensity of rainfalls to total rainfall was different in different areas of China,the contribution rate of heavy rainfall to total rainfall in most areas showed an increasing trend.( iii) Through comparing the rainfall and rainy days of six different intensity of rainfalls,it can be found that China’s heavy rainfall events are increasing and the rainfall intensity is developing towards extremes. 展开更多
关键词 RAINFALL classification RAINFALL and RAINY DAYS VARIATION trend RAINFALL contribution rate Heavy downpour China
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Contribution of Agricultural Input to Output in Hohhot City
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作者 Tinghe DENG Jie TIAN 《Asian Agricultural Research》 2013年第6期37-39,42,共4页
Based on the research data from the economics and management platform of Inner Mongolia Agricultural University,we analyze the changes in the input of agricultural production factors,such as farmland,labor and capital... Based on the research data from the economics and management platform of Inner Mongolia Agricultural University,we analyze the changes in the input of agricultural production factors,such as farmland,labor and capital in Hohhot City. Based on the principle of econometrics,we select the agricultural production input-output data in Hohhot City during the period 1992-2010,and establish the econometric model using Cobb-Douglas production factor,to estimate the rate of contribution of agricultural input to the growth of agricultural output value,and study the quantitative relations between agricultural input and agricultural output value. The results show that in Hohhot City,the contribution of chemical fertilizer input to the growth of agricultural output value is the greatest; the contribution of mechanical power to agricultural output value is still not brought into full play; the contribution of remaining production inputs ( including technical progress) accounts for 35. 69% . In the future,Hohhot City should pay more attention to the technical input to develop agriculture. 展开更多
关键词 AGRICULTURE INPUT and OUTPUT contribution rate Hoh
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Analysis of Factors Influencing Pregnancy Rate in Frozenthawed Embryo Transfer
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作者 Lu LI Xiao-xi SUN Jun-ling CHEN Xiao-hong GAO Yong-wei WANG Jie-wei TAO Li-nan CHENG 《Journal of Reproduction and Contraception》 CAS 2004年第4期239-244,共6页
Objective To analyse factors influencing the outcome of frozen-thawed embryo transfer (FET). Method A retrospective analysis was performed in our center on 129 thawing cycles from March 2001 to April 2003. The relat... Objective To analyse factors influencing the outcome of frozen-thawed embryo transfer (FET). Method A retrospective analysis was performed in our center on 129 thawing cycles from March 2001 to April 2003. The related parameters were compared between conceived and non-conceived cycles. Results There were totally 129 clinical pregnancies in these transfers (pregnancy rate: 27.1%). Frozen-thawed embryos were transferred to natural cycles and CC cycling and hormone replacement treatment had equal success. Groups of IVF and ICSI did not differ significantly in pregnancy rates (P〉0.05). The pregnancy rates for one, two, three and four pre-embryos transfer were 0, 20.0%,44.1% and 75.0%, respectively (P〈0.05). There were statistical differences between pregnancy group or non- pregnancy group in the endometrial thickness, CES, CES/No. of embryo. A higher pregnancy rate was observed in embryo transfers which had at least one 4-cell grade I embryo (d 2)(P〈0.01). Conclusions The most important factors influencing the implantation rate and pregnancy rate of frozen-thawed embryo transfer are age, endometrium thickness, and the number, morphology and growth rate of transferred frozen embryos of women participants. 展开更多
关键词 frozen thaw embryo transfer pregnancy rate
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Pregnancy Outcomes for Day 5 Versus Day 6 Single Frozen-thawed Blastocyst Transfer with Different Qualities of Embryos: A Large Matched-cohort Study 被引量:1
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作者 Qiong YU Hui HE +2 位作者 Xin-ling REN Shi-fu HU Lei JIN 《Current Medical Science》 SCIE CAS 2023年第2期297-303,共7页
Objective This study aimed to determine whether the day of blastocyst expansion affects pregnancy outcomes in frozen-thawed blastocyst transfer(FBT)cycles.Methods A retrospective match-cohort study was conducted.Patie... Objective This study aimed to determine whether the day of blastocyst expansion affects pregnancy outcomes in frozen-thawed blastocyst transfer(FBT)cycles.Methods A retrospective match-cohort study was conducted.Patients who underwent blastocyst transfer in frozen-thawed cycles at day 5 or 6 were matched for potential confounding factors.A total of 2207 matched pairs of FBT cycles were included from January 2016 to December 2019 in our Reproductive Medicine Center.Results The clinical pregnancy rate(CPR)and live birth rate(LBR)were significantly increased in day 5 blastocyst transfers when compared to day 6 blastocyst transfers,in terms of the same embryo quality.For FBT cycles with good-quality embryo,the CPR at day 5 and 6 was 61.30%and 57.56%,respectively(P=0.045),and the LBR was 44.79%and 36.16%,respectively(P<0.001).For FBT cycles with poor-quality embryo,the CPR at day 5 and 6 was 48.61%and 40.89%,respectively(P=0.006),and the LBR was 31.71%and 25.74%,respectively(P=0.019).The CPR for FBT cycles with good-quality embryo was statistically higher at day 6 than that at day 5 with poor-quality embryo transferred(57.56%vs.48.61%,P=0.001).Maternal age,anti-Müllerian hormone(AMH),endometrial thickness,embryo quality,and the day of blastocyst expansion were independently correlated with the CPR and LBR.The FBT cycles at day 5 had significantly higher CPR(adjusted odds ratio[OR]=1.246,95%confidence intervals[CI]:1.097–1.415,P=0.001)and LBR(adjusted OR=1.435,95%CI:1.258–1.637,P<0.001)than those at day 6.Conclusion The embryo quality is the primary indicator for FBT cycles.Day 5 blastocysts should be preferred when the quality of embryo at day 5 is the same as that at day 6. 展开更多
关键词 frozen-thawed blastocyst transfer day 5 versus day 6 embryo quality clinical pregnancy rate live birth rate
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Analyzing Service Rates for File Transfers in Peer-to-peer File Sharing Systems
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作者 王凯 潘理 李建华 《Journal of Donghua University(English Edition)》 EI CAS 2008年第6期700-705,共6页
When examining the file transfer performance in a peer-to-peer file sharing system, a fundamental problem is how to describe the service rate for a file transfer. In this paper, the problem is examined by analyzing th... When examining the file transfer performance in a peer-to-peer file sharing system, a fundamental problem is how to describe the service rate for a file transfer. In this paper, the problem is examined by analyzing the distribution of server-like nodes' upstream-bandwidth among their concurrent transfers. A sufficient condition for the service rate, what a receiver obtains for downloading a file, to asymptotically be uniform is presented. On the aggregate service rate for transferring a file in a system, a sufficient condition for it to asymptotically follow a Zipf distribution is presented. These asymptotic equalities are both in the mean square sense. These analyses and the sufficient conditions provide a mathematic base for modeling file transfer processes in peer-to-peer file sharing systems. 展开更多
关键词 PEER-TO-PEER file sharing system service rate file transfer Zipf distribution asymptotic equality
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Marcus'Electron Transfer Rate Revisited via a Rice-Ramsperger-Kassel-Marcus Analogue:A Uni ed Formalism for Linear and Nonlinear Solvation Scenarios
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作者 Yao Wang Yu Su +2 位作者 Rui-Xue Xu Xiao Zheng YiJing Yan 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2021年第4期462-470,I0003,共10页
In the pioneering work by R.A.Marcus,the solvation effect on electron transfer(ET)processes was investigated,giving rise to the celebrated nonadiabatic ET rate formula.In this work,on the basis of the thermodynamic so... In the pioneering work by R.A.Marcus,the solvation effect on electron transfer(ET)processes was investigated,giving rise to the celebrated nonadiabatic ET rate formula.In this work,on the basis of the thermodynamic solvation potentials analysis,we reexamine Marcus’formula with respect to the Rice-Ramsperger-Kassel-Marcus(RRKM)theory.Interestingly,the obtained RRKM analogue,which recovers the original Marcus’rate that is in a linear solvation scenario,is also applicable to the nonlinear solvation scenarios,where the multiple curve-crossing of solvation potentials exists.Parallelly,we revisit the corresponding Fermi’s golden rule results,with some critical comments against the RRKM analogue proposed in this work.For illustration,we consider the quadratic solvation scenarios,on the basis of physically well-supported descriptors. 展开更多
关键词 Electron transfer Marcus’rate formula Rice-Ramsperger-Kassel-Marcus theory Nonlinear solvation Fermi’s golden rule
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THE CALCULATION OF RATE CONSTANT OF ELECTRON TRANSFER REACTION AT ELECTRODES
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作者 Yin Sheng WU Zheng Yu ZHOU Ai Ping FU Chemistry Department, Qufu Normal University, Qufu, 273165. 《Chinese Chemical Letters》 SCIE CAS CSCD 1995年第1期59-62,共4页
After the electron transfers from the metal electrode to the Fe3+(H2O)(6) ion, the free energy of activation of this electron transfer reaction is calculated, then using the transition probability which is calculated ... After the electron transfers from the metal electrode to the Fe3+(H2O)(6) ion, the free energy of activation of this electron transfer reaction is calculated, then using the transition probability which is calculated by the perturbed degeneration theory and the Fermi golden rule,, the rate constant is gotten. Compared with the experimental results, it is satisfactory. 展开更多
关键词 AT THE CALCULATION OF rate CONSTANT OF ELECTRON transfer REACTION AT ELECTRODES
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