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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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Annoyance Rate Evaluation Method on Ride Comfort of Vehicle Suspension System 被引量:8
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作者 TANG Chuanyin ZHANG Yimin +1 位作者 ZHAO Guangyao MA Yan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第2期296-303,共8页
The existing researches of the evaluation method of ride comfort of vehicle mainly focus on the level of human feelings to vibration. The level of human feelings to vibration is influenced by many factors, however, th... The existing researches of the evaluation method of ride comfort of vehicle mainly focus on the level of human feelings to vibration. The level of human feelings to vibration is influenced by many factors, however, the ride comfort according to the common principle of probability and statistics and simple binary logic is tmable to reflect these uncertainties. The random fuzzy evaluation model from people subjective response to vibration is adopted in the paper, these uncertainties are analyzed from the angle of psychological physics. Discussing the traditional evaluation of ride comfort during vehicle vibration, a fuzzily random evaluation model on the basis of annoyance rate is proposed for the human body's subjective response to vibration, with relevant fuzzy membership function and probability distribution given. A half-car four degrees of freedom suspension vibration model is described, subject to irregular excitations from the road surface, with the aid of software Matlab/Simulink. A new kind of evaluation method for ride comfort of vehicles is proposed in the paper, i.e., the annoyance rate evaluation method. The genetic algorithm and neural network control theory are used to control the system. Simulation results are obtained, such as the comparison of comfort reaction to vibration environments between before and after control, relationship of annoyance rate to vibration frequency and weighted acceleration, based on ISO 2631 / 1 (1982), ISO 2631-1 (1997) and annoyance rate evaluation method, respectively. Simulated assessment results indicate that the proposed active suspension systems prove to be effective in the vibration isolation of the suspension system, and the subjective response of human being can be promoted from very uncomfortable to a little uncomfortable. Furthermore, the novel evaluation method based on annoyance rate can further estimate quantitatively the number of passengers who feel discomfort due to vibration. A new analysis method of vehicle comfort is presented. 展开更多
关键词 evaluation method ride comfort annoyance rate genetic algorithm neural network
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Self-determinate evaluation method based on condition of weights non-dictatorial rate 被引量:3
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作者 Zhang Danning Yi Pingtao Guo Yajun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第2期310-320,共11页
The condition of weightes non-dictatorship is extended and a comprehensive evaluae method emboding self-determinate which is combined with competitive view optimization principles is built. The basic process includes ... The condition of weightes non-dictatorship is extended and a comprehensive evaluae method emboding self-determinate which is combined with competitive view optimization principles is built. The basic process includes simulating the model of economic man's self-benefit bahaviors, taking the place of experts to evaluate, bringing in the model of minimizing the sum of included angles to integrate the information of multiple objects and put the objects in order finally. The method has the advangtages of less dependendence on the subjective information, plenty of information, fair process and simple caculating. Finally, an application example is given to illustrate the effectiveness of the proposed method. 展开更多
关键词 condition of weights non-dictatorial rate principle of competitive view optimization self-determinate evaluation comprehensive evaluation
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A Dynamic Bayesian-Based Comprehensive Trust Evaluation Model for Dispersed Computing Environment
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作者 Hongwen Hui Zhengxia Gong +1 位作者 Jianwei An Jianzhong Qi 《China Communications》 SCIE CSCD 2023年第2期278-288,共11页
Dispersed computing is a new resourcecentric computing paradigm.Due to its high degree of openness and decentralization,it is vulnerable to attacks,and security issues have become an important challenge hindering its ... Dispersed computing is a new resourcecentric computing paradigm.Due to its high degree of openness and decentralization,it is vulnerable to attacks,and security issues have become an important challenge hindering its development.The trust evaluation technology is of great significance to the reliable operation and security assurance of dispersed computing networks.In this paper,a dynamic Bayesian-based comprehensive trust evaluation model is proposed for dispersed computing environment.Specifically,in the calculation of direct trust,a logarithmic decay function and a sliding window are introduced to improve the timeliness.In the calculation of indirect trust,a random screening method based on sine function is designed,which excludes malicious nodes providing false reports and multiple malicious nodes colluding attacks.Finally,the comprehensive trust value is dynamically updated based on historical interactions,current interactions and momentary changes.Simulation experiments are introduced to verify the performance of the model.Compared with existing model,the proposed trust evaluation model performs better in terms of the detection rate of malicious nodes,the interaction success rate,and the computational cost. 展开更多
关键词 dispersed computing trust evaluation model malicious node interaction success rate detection rate
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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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Effect of Rating Scales and Test Parts of Body on the Evaluation Results of Fabric-evoked Prickle
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作者 王革辉 RON Postle 张渭源 《Journal of Donghua University(English Edition)》 EI CAS 2006年第3期102-105,共4页
The effect of rating scales and test parts of body on the fabric-evoked prickle evaluation results are studied by carrying out subjective evaluation tests under controlled environment conditions (24 4±1)℃, (6... The effect of rating scales and test parts of body on the fabric-evoked prickle evaluation results are studied by carrying out subjective evaluation tests under controlled environment conditions (24 4±1)℃, (65 =l= 5) %RH. Ten college female students aged about 20 were chosen as the subjects, who have participated a preliminary training on subjective prickle evaluation. The prickle of a range of 9 light-weight worsted woven wool and wool blend fabrics and a cotton fabric were tested by using a 1 - 5 rating scale and using a 0 - 10 rating scale respectively at different test parts of body respectively such as forearm, upper arm ball and neck back. The test results were statistically analyzed. It is found that there is a significant correlation coefficient between the evaluation results of using the 1 - 5 rating scale and of using the 0- 10 rating scale. It is also found that there are highly significant correlation coefficients between the evaluation results of using the forearm prickle test and the neck back prickle test, between the evaluation results of using the neck back prickle test and the upper arm ball prickle test, and between the evaluation results of using the forearm prickle test and the upper arm ball prickle test. It is suggested that the forearm prickle test is preferable in evaluating fabric-evoked prickle for its convenience and sensitivity. 展开更多
关键词 subjective evaluation fabric-evoked prickle rating scale forearm test.
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An Evaluation of the Impact of the Integrated Project on Rural Women from a Gender Perspective
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《China Population Today》 2002年第1期15-17,共3页
关键词 PROJECT In RATE An evaluation of the Impact of the Integrated Project on Rural Women from a Gender Perspective
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Electrochemical Determination of Rate Constants for Reactions of OH and its Application in the Evaluation of Anti-Oxidant Actions of Rheum
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作者 Ruo Mei GAO Zhuo Bin YUAN Fu Ming Lm and Hong Bo DING(Department of Chemistry, Graduate School, USTC, Acaddria Sinica, Beijing 100039) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第5期427-430,共4页
A single-sweep oscillopolarographic procedure is descrital which allows detethenahon of rateconstants for reachons of oH. For a wide range of compounds, the results fit well with rate constantspreviously obtained with... A single-sweep oscillopolarographic procedure is descrital which allows detethenahon of rateconstants for reachons of oH. For a wide range of compounds, the results fit well with rate constantspreviously obtained with other methods. Rate constants for reactions of six kinds of active compoundscontalned in rheum, a tradihonal Chinese herb, have been deteboned by this method. Rcationmechanism ha5 also been discussed. 展开更多
关键词 OH Electrochemical Determination of Rate Constants for Reactions of OH and its Application in the evaluation of Anti-Oxidant Actions of Rheum
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Evaluation of Variable Rate Technology for Fertilizer Application in Permanent Pastures
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作者 J. M. Serrano J. M. Peca Shahidian 《Journal of Agricultural Science and Technology(A)》 2011年第4X期489-499,共11页
This paper describes the field tests carried out to evaluate the new Vicon RS-EDW centrifugal fertilizer spreader, to be used in Precision Agriculture. The results of initial dynamic calibration tests showed a signifi... This paper describes the field tests carried out to evaluate the new Vicon RS-EDW centrifugal fertilizer spreader, to be used in Precision Agriculture. The results of initial dynamic calibration tests showed a significant and systematic difference between the application rates of the two discs (about 20%). This difference had to be corrected by the manufacturer that carried out the necessary changes to the electric actuators. The fertilizer spreader had good distribution homogeneity, considering different working velocities and different positions in the parcel. The pattern distribution curve for 18% super phosphate fertilizer led to an effective working width of 28 meters, with a coefficient of variation of 15%. The longitudinal test, under experimental working conditions led to a machine delay time of 6-7 seconds. The results show an actual fertilization application density between 74%-90% of that determined for each location. These results confirm that the spreader can be used to spread fertilizer differentially in the field. 展开更多
关键词 Calibration centrifugal fertilizer spreader evaluation precision agriculture variable rate technology.
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Technical evaluation system of co-extraction of coal and gas 被引量:8
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作者 Liang Bing Sun Weiji +1 位作者 Qi Qingxin Li Hongyan 《International Journal of Mining Science and Technology》 SCIE EI 2012年第6期891-894,共4页
Coal and gas are two important resources in China,and it is an effective way to recycle them with the method of co-extraction of coal and gas.In view of actual situation of China's co-extraction of coal and gas,th... Coal and gas are two important resources in China,and it is an effective way to recycle them with the method of co-extraction of coal and gas.In view of actual situation of China's co-extraction of coal and gas,this research adopts the science evaluation of gas extraction of coal by the method of quantitative evaluation,and preliminarily establishes the technical evaluation system of co-extraction of coal and gas.Technical evaluation system of co-extraction of coal and gas includes safety evaluation,economic evaluation and resource recovery evaluation in the process of mining coal and gas.In addition,this paper results in the selected evaluation parameters and target functions that are used in the three evaluation methods.The establishment of evaluation system for co-extraction of coal and gas plays an important theoretical significance and guiding role in co-extraction of coal and gas for China's coal enterprises. 展开更多
关键词 Co-extraction of COAL and GAS evaluation system Safety ECONOMIC RESOURCE RECOVERY rate
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A quantitative model for danger degree evaluation of staged operation of earth dam reservoir in flood season and its application 被引量:3
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作者 Chong-xun Mo Gui-yan Mo +3 位作者 Qing Yang Yu-li Ruan Qing-ling Jiang Ju-liang Jin 《Water Science and Engineering》 EI CAS CSCD 2018年第1期81-87,共7页
Based on the natural disaster risk evaluation mode, a quantitative danger degree evaluation model was developed to evaluate the danger degree of earth dam reservoir staged operation in the flood season. A formula for ... Based on the natural disaster risk evaluation mode, a quantitative danger degree evaluation model was developed to evaluate the danger degree of earth dam reservoir staged operation in the flood season. A formula for the overtopping risk rate of the earth dam reservoir staged operation was established, with consideration of the joint effect of flood and wind waves in the flood sub-seasons with the Monte Carlo method, and the integrated overtopping risk rate for the whole flood season was obtained via the total probability approach. A composite normalized function was used to transform the dam overtopping risk rate into the danger degree, on a scale of 0-1. Danger degree gradating criteria were divided by four significant characteristic values of the dam overtopping rate, and corresponding guidelines for danger evaluation are explained in detail in this paper. Examples indicated that the dam overtopping danger degree of the Chengbihe Reservoir in China was 0.33-0.57, within the range of moderate danger level, and the flood-limiting water level (FLWL) can be adjusted to 185.00 m for the early and main flood seasons, and 185.00-187.50 m for the late flood season. The proposed quantitative model offers a theoretical basis for determination of the value of the danger degree of an earth dam reservoir under normal operation as well as the optimal scheduling scheme for the reservoir in each stage of the flood season. 展开更多
关键词 Reservoir staged operation in flood season Earth dam Danger degree Quantitative evaluation Overtopping risk rate
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Risk assessment of corroded casing based on analytic hierarchy process and fuzzy comprehensive evaluation 被引量:4
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作者 Sheng-Shan Chen Han-Xiang Wang +3 位作者 Hao Jiang Ya-Nan Liu Yan-Xin Liu Xiao-Xiao Lv 《Petroleum Science》 SCIE CAS CSCD 2021年第2期591-602,共12页
Casing corrosion during CO2 injection or storage results in significant economic loss and increased production risks.Therefore,in this paper,a corroded casing risk assessment model based on analytic hierarchy process ... Casing corrosion during CO2 injection or storage results in significant economic loss and increased production risks.Therefore,in this paper,a corroded casing risk assessment model based on analytic hierarchy process and fuzzy comprehensive evaluation is established to identify potential risks in time.First,the corrosion rate and residual strength characteristics are analyzed through corrosion tests and numerical simulations,respectively,to determine the risk factors that may lead to an accident.Then,an index system for corroded casing risk evaluation is established based on six important factors:temperature,CO2 partial pressure,flow velocity,corrosion radius,corrosion depth and wellhead pressure.Subsequently,the index weights are calculated via the analytic hierarchy process.Finally,the risk level of corroded casing is obtained via the fuzzy comprehensive evaluation.The corroded casing risk assessment model has been verified by a case well,which shows that the model is valuable and feasible.It provides an effective decision-making method for the risk evaluation of corroded casing in CO2 injection well,which is conductive to improve the wellbore operation efficiency. 展开更多
关键词 Corrosion rate Residual strength Analytic hierarchy process Fuzzy comprehensive evaluation
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Evaluation on Sixty-eight Rice Germplasms in Cold Tolerance at Germination Stage 被引量:12
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作者 Peyman SHARIFI 《Rice science》 SCIE 2010年第1期77-81,共5页
Sixty-eight rice germplasms were used for cold tolerance evaluation at the germination stage in laboratory. Seeds of rice germplasms germinated at three different temperatures containing low temperature (constant 13&... Sixty-eight rice germplasms were used for cold tolerance evaluation at the germination stage in laboratory. Seeds of rice germplasms germinated at three different temperatures containing low temperature (constant 13°C for 28 days), alternative temperature (a temperature cycle of 12 h at 20°C and 12 h at 23°C for 14 days) and control (constant 26°C for 7 days). Analysis of variance revealed that temperature had a significant effect on germination rate, coleoptile length and radicle length. Germination rate was strongly affected by the low temperature and alternative treatments. Stress of low temperature at the germination stage on the tested rice germplasms caused a reduction in final germination rate and the lengths of coleoptile and radicle. The normal and healthy seeds began to germinate within 36 h after imbibition and germination were completed on the 7th day in the control, but delayed under the low and alternative temperature treatments. The low and alternative temperature treatments delayed the growth of coleoptile and radicle compared to the control, and the average lengths of coleoptile and radicule were strongly inhibited with the decreasing temperature in all of the tested germplasms. Taichung, a semi-dwarf, low amylose content and early maturing rice variety, showed a significantly higher germination rate at the three temperature treatments and its coleoptile length was significantly higher than other germplasms. 展开更多
关键词 rice cold tolerance germination rate coleoptile length radicle length evaluation
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Evaluation of directly observed treatment short courses at a secondary health institution in Ibadan,Oyo State,Southwestern Nigeria 被引量:1
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作者 Olajire A.Adegoke Olalekan A.Orokotan 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2013年第12期952-959,共8页
Objective:To evaluate the success rate of tuberculosis intervention programme at a specialist hospital in(?)badan,Nigeria through a retrospective study as well as carry out physicochemical evaluation of anti-tuberculo... Objective:To evaluate the success rate of tuberculosis intervention programme at a specialist hospital in(?)badan,Nigeria through a retrospective study as well as carry out physicochemical evaluation of anti-tuberculous agents as a way of eliminating drug-related failure.Methods:The retrospective study involved the use of quarterly tuberculosis central register at the Government Chest Hospital,(?)badan between 1st quarter(2003)to 4th quarter(2009).Relevant data were extracted from these register with the aid of data collection forms.The basic physicochemical analyses of the drugs given to the patients were also carried out using the International Pharmacopoeia methods.Results:All the drugs examined for their physicochemical properties passed the International Pharmacopeia recommended tests.A total number of 1 260 patients enrolled at the hospital were assessed through case notes.This comprises of 59.4%males of which69.23%new cases were also males.There was a significant(P<0.05)patient enrollment across the quarters for the seven years.An overall 80.24%cure rate over the 7-period was obtained which is less than the WHO target of 85%.Cure rates were better in females than males.Failure treatment outcomes such as positive(1.51%),deaths(8.73%),defaulted(3.33%)and transferred out(5.95%)were recorded though not statistically significant(P>0.05).Failure rates in all categories were higher in males than females(P>0.05).Conclusions:More enlightenment and counseling is still required to meet up with the target for TB control. 展开更多
关键词 TUBERCULOSIS DOTS therapy Success rate Anti-TB drugs PHYSICOCHEMICAL evaluation
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Quality evaluation of groundwater in the North China Plain 被引量:2
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作者 FEI Yu-hong ZHANG Zhao-ji +2 位作者 LI Ya-song GUO Chun-yan TIAN Xia 《Journal of Groundwater Science and Engineering》 2015年第4期306-315,共10页
This paper presents a method combining single-indicator comprehensive evaluation and influence factor identification to measure groundwater quality. This method not only reflects groundwater quality classification wit... This paper presents a method combining single-indicator comprehensive evaluation and influence factor identification to measure groundwater quality. This method not only reflects groundwater quality classification with clear physical significance, but also divides the possibilities of man-made pollution in regional groundwater. The paper selects 6 063 representative groundwater wells in the North China Plain to evaluate 49 groundwater inorganic and organic index and comes to a conclusion: Controlled by geological environment and hydrogeological conditions, the groundwater quality in the North China Plain deteriorates from the bottom of maintain to coastal area, with Class I to III groundwater decreasing from 49% to 3.9% while Class V groundwater increasing from 21% to 86.9%; the quality of deep groundwater is better than that of shallow groundwater; the contribution rate of manganese, total hardness, total dissolved solids and iodide in shallow groundwater to over-III type water exceeds 50%; the contribution rate of nitrite in pollution index reaches 20%; while heavy metal and organic indexes have limited impact on regional groundwater quality. The North China Plain is an important economic area in China. Over decades, it has witnessed intense human activities, and water resource quantity demanded has been far greater than quantity supplied. Due to scarce surface water resource, groundwater becomes the pillar supporting regional economic development. This has led to increasing groundwater exploitation and development. According to statistics, the exploitation degree of shallow groundwater reaches 105% in the North China Plain and 118% in the Hebei Plain; the exploitation degree of deep groundwater reaches 143% in the North China Plain and 163% in the Hebei Plain. The serious over-exploitation of groundwater brings various geological environmental problems, with the worsening of groundwater quality being a typical one. Besides impact brought by human activities, the poor quality of natural water in the North China Plain is also an important factor. Therefore, to understand the current regional groundwater quality situation and to master influence factors and influence degree can provide reliable scientific protection for regional economic development. 展开更多
关键词 North China plain Groundwater quality evaluation Contribution rate
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Study of evaluation method for the overseas oil and gas investment based on risk compensation 被引量:3
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作者 Zu-Xin Li Jian-Ye Liu +1 位作者 Dong-Kun Luo Jian-Jun Wang 《Petroleum Science》 SCIE CAS CSCD 2020年第3期858-871,共14页
The overseas oil and gas investment evaluation is one of the core tasks in overseas investment of oil and gas companies,among which risk evaluation and benefit evaluation are the most important.This paper sets forth t... The overseas oil and gas investment evaluation is one of the core tasks in overseas investment of oil and gas companies,among which risk evaluation and benefit evaluation are the most important.This paper sets forth transmission paths of risk factors to the investment benefit by identifying 14 overseas oil and gas investment risks in four categories.On the basis of the concept of risk compensation,different compensation mechanisms specific to each risk are designed.The risk and benefit are integrated objectively to develop a comprehensive evaluation model by correcting the recoverable reserve,adjusting benefit evaluation parameters such as investments on exploration and development,and compensating for the changes in risk factors with time through dynamic discount rate.Moreover,two cases studies,namely the evaluations of Project A in Sudan and comparison among Blocks A–G,are used to describe usage method and applicable scope of such evaluation model,respectively.According to the results,oil price is a key influencing factor for enterprise internal risk and industrial risk.Risk compensation reduces comprehensive benefit of overseas oil and gas investment and undermines the investment feasibility and priority of blocks.The research findings of this paper are free from the effects of some subject factors and avoid multi-objective decision making,and also avoid the undesired repeated calculation of risk factors. 展开更多
关键词 Overseas oil and gas investment Investment evaluation Risk compensation Dynamic discount rate Comprehensive benefit
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Evaluation of rope shovel operators in surface coal mining using a Multi-Attribute Decision-Making model 被引量:2
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作者 Vukotic Ivana Kecojevic Vladislav 《International Journal of Mining Science and Technology》 SCIE EI 2014年第2期259-268,共10页
Rope shovels are used to dig and load materials in surface mines. One of the main factors that influence the production rate and energy consumption of rope shovels is the performance of the operator. This paper presen... Rope shovels are used to dig and load materials in surface mines. One of the main factors that influence the production rate and energy consumption of rope shovels is the performance of the operator. This paper presents a method for evaluating rope shovel operators using the Multi-Attribute Decision-Making (MADM) model. Data used in this research were collected from an operating surface coal mine in the southern United States. The MADM model consists of attributes, their weights of importance, and alter- natives. Shovel operators are considered the alternatives, The energy consumption model was developed with multiple regression analysis, and its variables were included in the MADM model as attributes. Preferences with respect to min/max of the defined attributes were obtained with multi-objective opti- mization. Multi-objective optimization was conducted with the overall goal of minimizing energy con- sumption and maximizing production rate. Weights of importance of the attributes were determined by the Analytical Hierarchy Process (AHP), The overall evaluation of operators was performed by one of the MADM models, i.e., PROMETHEE If. The research results presented here may be used by mining professionals to held evaluate the performance of rode shovel operators in surface mining. 展开更多
关键词 Rope shovel Operator evaluation Production rate Energy consumption AHP
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Evaluation of Tomato Genetic Resources for Response to Water Deficit
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作者 Adriana Sacco Barbara Greco +2 位作者 Antonio Di Matteo Rosalba De Stefano Amalia Barone 《American Journal of Plant Sciences》 2013年第12期131-145,共15页
Water deficit strongly affects plant yield and quality. However, plants can minimize drought injury by adaptation mechanisms that have evolved to escape harmful conditions. The response to water deprivation is a compl... Water deficit strongly affects plant yield and quality. However, plants can minimize drought injury by adaptation mechanisms that have evolved to escape harmful conditions. The response to water deprivation is a complex trait controlled by several genes. In order to gain a deeper understanding of drought response mechanisms in tomato, a collection of 27 genotypes was studied under different water deficit conditions. Since developmental stages might be differently influenced by drought, analyses were carried out on young plantlets during fruit setting. The only genotype that showed good performances both as water retention and fruit production was the ecotype Siccagno. All the genotypes were analyzed at molecular level with the aim of detecting structural polymorphisms in selected stress-responsive genes. In addition, the expression level of a number of these genes was measured in the genotypes more tolerant to water deficit. Many polymorphisms were detected in six stress-responsive genes, and some could imply significant modifications in the protein structure. Furthermore, the expression analysis by RT-qPCR of three stress-responsive genes allowed arguing that a higher level of expression of the gene erd15 might be related to the better response to water deficit exhibited by Siccagno. Similarly, the lower expression of eight genes in the same genotype analysed through a microarray experiment confirmed the involvement of these stress-related genes in the tomato response to drought. Further investigations are required for a better comprehension of the mechanisms underlying response to water deficit in tomato by exploiting the genetic resource identified as more tolerant. The use of new technologies able to globally analyze structural polymorphism and expression level of genes will succeed to identify crucial genes involved in stress response in the ecotype Siccagno grown under different water regimes. 展开更多
关键词 Drought-Tolerance WATER Loss Rate Relative WATER Content Yield evaluation Gene POLYMORPHISMS
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Establishment of Quick Testing Efficiency Evaluation Model and Analysis of Related Factors
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作者 Dan Li 《Food and Nutrition Sciences》 2016年第13期1232-1240,共9页
Objective: “Rapid screening, targeted sampling, objective test” is an efficient test model. The factors affecting the efficiency include false screening rate, missing rate and rapid screening time. However, only mis... Objective: “Rapid screening, targeted sampling, objective test” is an efficient test model. The factors affecting the efficiency include false screening rate, missing rate and rapid screening time. However, only missing rate and accuracy have been used as technical requirements to evaluate rapid screening method. In this study, efficiency was regarded as evaluation index of quick testing method. Method: The evaluation model of quick testing efficiency was established by comparing time of routine testing and quick testing. By simulation calculation, the effect factors such as rapid screening time, false screening rate, missing rate and defective rate were analyzed. Results: The calculation formula of efficiency was derived. Simulation results showed that the lower defective rate, the higher efficiency;the smaller missing rate, false screening rate, or screening time, the higher efficiency and the degree of improving efficiency is related to defective rate;sometimes, the screening time is the most important factor affecting the efficiency. In certain cases, if the false screening rate or missing rate is 50%, the efficiency can be increased by more than 10 times. Conclusions: Taken together, this study highlighted a role of efficiency which functioned as an index to evaluate rapid screening. Quick testing efficiency evaluation model can be used for the calculation efficiency, and can be used to analysis the relationship between efficiency and the influence factors, and can provide the theoretical foundation for rapid screening method development and evaluation. 展开更多
关键词 Efficiency evaluation Rapid Screening Time Missing Rate False Screening Rate
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