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Regional-scale risk assessment of forest fires induced by distribution lines via a hybrid approach
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作者 Hongrui Jiang Jiaqing Zhang +3 位作者 Long Ding Binbin Zhang Tao Sun Jie Ji 《中国科学技术大学学报》 CSCD 北大核心 2024年第12期50-61,I0007,I0009,共14页
Forest fire accidents caused by distribution line faults occur frequently,resulting in heavy impacts on people’s safety and social and economic development.Currently,there are few risk assessments for forest fires in... Forest fire accidents caused by distribution line faults occur frequently,resulting in heavy impacts on people’s safety and social and economic development.Currently,there are few risk assessments for forest fires induced by over-head distribution lines,and existing assessment methods may have difficulties in data acquisition.On this basis,a novel as-sessment framework based on an analytic hierarchy process,a Bayesian network and a Fussel-Vesely importance metric is proposed in this paper.The framework combines field research and historical operation and maintenance data to assess the regional-scale risk of forest fires induced by overhead distribution lines to derive the probability of forest fires and to identify high-risk lines and key hazard events in the assessment region.Finally,taking the southern Anhui region as an ex-ample,the annual fire probability of forest fires induced by overhead distribution lines in the southern Anhui region is 5.88%,and rectification measures are proposed.This study provides management with a complete assessment framework that optimizes the difficulty of data collection and allows for additional targeted corrective measures to be proposed for the entire region and route on the basis of the assessment results. 展开更多
关键词 overhead distribution lines regional risk assessment forest fire Bayesian network hazard identification
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FAULT TREE ANALYSIS OF SPONTANEOUS COMBUSTION OF SULPHIDE ORES AND ITS RISK ASSESSMENT 被引量:21
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作者 Wu Chao(Department of Resources Exploitation Engineering, Central South University of Technology, Changsha, 410083, China ) 《Journal of Central South University》 SCIE EI CAS 1995年第2期77-80,共4页
A logic fault tree of mine spontaneous combustion of sulphide ores was built by the fault tree analysis (FTA) based on a lot of mechanism investigation of sulphide ore spontaneous combustion in more than ten mines an... A logic fault tree of mine spontaneous combustion of sulphide ores was built by the fault tree analysis (FTA) based on a lot of mechanism investigation of sulphide ore spontaneous combustion in more than ten mines and review of a great amount of relevant 展开更多
关键词 FAULT TREE analysis SULPHIDE ORES SPONTANEOUS COMBUSTION risk assessment
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Surface water quality and potential health risk assessments in Changsha-Zhuzhou-Xiangtan section of Xiangjiang River, China 被引量:7
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作者 JIANG Dong-yi YANG Jin-qin +3 位作者 WANG Yun-yan LIAO Qi LONG Zhe ZHOU San-yang 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第12期3252-3260,共9页
The Changsha-Xiangtan-Zhuzhou City Group is a heavy industrial district and accepted as the serious pollution area in the Xiangjiang River basin.In this study,7 metals(Pb,Hg,Cd,As,Zn,Cu and Se)and the river water qual... The Changsha-Xiangtan-Zhuzhou City Group is a heavy industrial district and accepted as the serious pollution area in the Xiangjiang River basin.In this study,7 metals(Pb,Hg,Cd,As,Zn,Cu and Se)and the river water quality parameters including pH,dissolved oxygen(DO),Escherichia coli(E.coli),potassium permanganate index(CODMn),dichromate oxidizability(CODCr),five-day biochemical oxygen demand(BOD5),ammonia nitrogen(NH4+-N),total nitrogen(TN),total phosphorus(TP)and fluoride(F)in 18 sampling sites of the Changsha-Xiangtan-Zhuzhou section are monthly monitored in 2016,which is the year to step into the second stage of the“Xiangjiang River Heavy Metal Pollution Control Implementation Plan”.It is found that E.coli,TN and TP are the main pollutants in the Changsha-Zhuzhou-Xiangtan section,and the pollution of heavy metal is not serious but As with potential risk to local people especially children should be concerned.In addition,Xiangtan city is mainly featured with heavy metal pollution,while Zhuzhou and Changsha city are both featured with other pollutants from municipal domestic sewage. 展开更多
关键词 Xiangjiang River surface water heavy metal water quality assessment human health risk assessment
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Risk assessment of water inrush in tunnels based on attribute interval recognition theory 被引量:8
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作者 WANG Sheng LI Li-ping +3 位作者 CHENG Shuai HU Hui-jiang ZHANG Ming-guang WEN Tao 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第2期517-530,共14页
Water inrush is one of the most serious geological hazards in underground engineering construction.In order to effectively prevent and control the occurrence of water inrush,a new attribute interval recognition theory... Water inrush is one of the most serious geological hazards in underground engineering construction.In order to effectively prevent and control the occurrence of water inrush,a new attribute interval recognition theory and method is proposed to systematically evaluate the risk of water inrush in karst tunnels.Its innovation mainly includes that the value of evaluation index is an interval rather than a certain value;the single-index attribute evaluation model is improved non-linearly based on the idea of normal distribution;the synthetic attribute interval analysis method based on improved intuitionistic fuzzy theory is proposed.The TFN-AHP method is proposed to analyze the weight of evaluation index.By analyzing geological factors and engineering factors in tunnel zone,a multi-grade hierarchical index system for tunnel water inrush risk assessment is established.The proposed method is applied to ventilation incline of Xiakou tunnel,and its rationality and practicability is verified by comparison with field situation and evaluation results of other methods.In addition,the results evaluated by this method,which considers that water inrush is a complex non-linear system and the geological conditions have spatial variability,are more accurate and reliable.And it has good applicability in solving the problem of certain and uncertain problem. 展开更多
关键词 water inrush risk assessment attribute interval recognition model TFN-AHP
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Risk assessment model of tunnel water inrush based on improved attribute mathematical theory 被引量:12
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作者 YANG Xiao-li ZHANG Sheng 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第2期379-391,共13页
Tunnel water inrush is one of the common geological disasters in the underground engineering construction.In order to effectively evaluate and control the occurrence of water inrush,the risk assessment model of tunnel... Tunnel water inrush is one of the common geological disasters in the underground engineering construction.In order to effectively evaluate and control the occurrence of water inrush,the risk assessment model of tunnel water inrush was proposed based on improved attribute mathematical theory.The trigonometric functions were adopted to optimize the attribute mathematical theory,avoiding the influence of mutation points and linear variation zones in traditional linear measurement functions on the accuracy of the model.Based on comprehensive analysis of various factors,five parameters were selected as the evaluation indicators for the model,including tunnel head pressure,permeability coefficient of surrounding rock,crushing degree of surrounding rock,relative angle of joint plane and tunnel section size,under the principle of dimension rationality,independence,directness and quantification.The indicator classifications were determined.The links among measured data were analyzed in detail,and the objective weight of each indicator was determined by using similar weight method.Thereby the tunnel water inrush risk assessment model is established and applied in four target segments of two different tunnels in engineering.The evaluation results and the actual excavation data agree well,which indicates that the model is of high credibility and feasibility. 展开更多
关键词 tunnel water inrush risk assessment model attribute mathematical theory nonlinear measurement function similar weight method
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Application of fuzzy analytic hierarchy process and neural network in power transformer risk assessment 被引量:8
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作者 李卫国 俞乾 罗日成 《Journal of Central South University》 SCIE EI CAS 2012年第4期982-987,共6页
In operation,risk arising from power transformer faults is of much uncertainty and complicacy.To timely and objectively control the risks,a transformer risk assessment method based on fuzzy analytic hierarchy process(... In operation,risk arising from power transformer faults is of much uncertainty and complicacy.To timely and objectively control the risks,a transformer risk assessment method based on fuzzy analytic hierarchy process(FAHP) and artificial neural network(ANN) from the perspective of accuracy and quickness is proposed.An analytic hierarchy process model for the transformer risk assessment is built by analysis of the risk factors affecting the transformer risk level and the weight relation of each risk factor in transformer risk calculation is analyzed by application of fuzzy consistency judgment matrix;with utilization of adaptive ability and nonlinear mapping ability of the ANN,the risk factors with large weights are used as input of neutral network,and thus intelligent quantitative assessment of transformer risk is realized.The simulation result shows that the proposed method increases the speed and accuracy of the risk assessment and can provide feasible decision basis for the transformer risk management and maintenance decisions. 展开更多
关键词 fuzzy analytic hierarchy process risk assessment power transformer artificial neutral network
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Risk assessment: an approach to control hazards in mines 被引量:2
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作者 Shis Bhattacherjee 《中国安全生产科学技术》 CAS CSCD 2014年第S1期129-135,共7页
Accidents and injuries related to work are major occupational health problems in most of the industrialized countries.Traditional approaches to manage workplace safety in mines have mainly focused on job redesign and ... Accidents and injuries related to work are major occupational health problems in most of the industrialized countries.Traditional approaches to manage workplace safety in mines have mainly focused on job redesign and technical aspects of engineering systems.It is being realized that compliance to rules and regulations of mines is a prerequisite;however,it is not sufficient to achieve further reduction in accident and injury rates in mines.Proactive approaches are necessary to further improve the safety standards in mines.Unsafe conditions and practices in mines lead to a number of accidents,which in turn may cause loss and injury to human lives,damages to property,and loss of production.Hazard identification and risk assessment is an important task for the mining industry which needs to consider all the risk factors at workplaces.Applications of risk management approaches in mines are necessary to identify and quantify potential hazards and to suggest effective solutions.In this paper,the following risk estimation techniques were discussed:(i)DGMS(Directorate General of Mines Safety,India)risk rating criterion,and(ii)a matrix based approach.The proposed tools were demonstrated through an application in an opencast coal mine in India.It was inferred that the risk assessment approach can be used as an effective tool to indentify and control hazards in mines. 展开更多
关键词 HAZARD identification risk assessment DGMS MATRIX based APPROACH
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Risk Assessment of Coal Mine Water Hazard Based on Three-Dimensional Model of Geology and Underground Space 被引量:1
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作者 Kai Zhang~1,Ming Huang~1,Bin Tang~2,Fan Cui~1 1.Laboratory of Coal Resources and Mine Safety,China University of Mining and Technology,Beijing 100083,China. 2.China Water Investment Co.Ltd,Beijing 100053,China 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期279-279,共1页
Mine safety have top-five disasters,which including the water,gas,fire,dust and geological dynamic disaster.The coal mine water disaster is one of the important factors which restricted the development of China’s coa... Mine safety have top-five disasters,which including the water,gas,fire,dust and geological dynamic disaster.The coal mine water disaster is one of the important factors which restricted the development of China’s coal production.It is showed by statistics that 60%of mine accidents are affected by groundwater,which not only result in the production losses,casualties and a variety of 展开更多
关键词 DISASTER risk assessment THREE-DIMENSIONAL model of GEOLOGY and UNDERGROUND space emergency RESCUE
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Risk assessment of floor water inrush in coal mines based on MFIM-TOPSIS variable weight model 被引量:9
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作者 ZHANG Guan-da XUE Yi-guo +3 位作者 BAI Cheng-hao SU Mao-xin ZHANG Kai TAO Yu-fan 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第8期2360-2374,共15页
Floor water inrush is one of the main types of coal mine water hazards.With the development of deep mining,the prediction and evaluation of floor water inrush is particularly significant.This paper proposes a variable... Floor water inrush is one of the main types of coal mine water hazards.With the development of deep mining,the prediction and evaluation of floor water inrush is particularly significant.This paper proposes a variable weight model,which combines a multi-factor interaction matrix(MFIM)and the technique for order performance by similarity to ideal solution(TOPSIS)to implement the risk assessment of floor water inrush in coal mines.Based on the MFIM,the interaction between seven evaluation indices,including the confined water pressure,water supply condition and aquifer water yield property,floor aquifuge thickness,fault water transmitting ability,fracture development degree,mining depth and thickness and their influence on floor water inrush were considered.After calculating the constant weights,the active degree evaluation was used to assign a variable weight to the indices.The values of the middle layer and final risk level were obtained by TOPSIS.The presented model was successfully applied in the 9901 working face in the Taoyang Mine and four additional coal mines and the results were highly consistent with the engineering situations.Compared with the existing nonlinear evaluation methods,the proposed model had advantages in terms of the weighting,principle explanation,and algorithm structure. 展开更多
关键词 floor water inrush risk assessment multi-factor interaction matrix(MFIM) technique for order performance by similarity to ideal solution(TOPSIS) variable weight
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Integrated evaluation system under randomness and fuzziness for groundwater contamination risk assessment in a little town, Central China 被引量:2
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作者 祝慧娜 袁兴中 +4 位作者 梁婕 刘永德 尹娟 江洪炜 黄华军 《Journal of Central South University》 SCIE EI CAS 2014年第3期1044-1050,共7页
An integrated evaluation system under randomness and fuzziness was developed in this work to systematically assess the risk of groundwater contamination in a little town, Central China. In this system, randomness of t... An integrated evaluation system under randomness and fuzziness was developed in this work to systematically assess the risk of groundwater contamination in a little town, Central China. In this system, randomness of the parameters and the fuzziness of the risk were considered simultaneously, and the exceeding standard probability of contamination and human health risk due to the contamination were integrated. The contamination risk was defined as a combination of "vulnerability" and "hazard". To calculate the value of "vulnerability", pollutant concentration was simulated by MODFLOW with random input variables and a new modified health risk assessment(MRA) model was established to analyze the level of "hazard". The limit concentration based on environmental-guideline and health risk due to manganese were systematically examined to obtain the general risk levels through a fuzzy rule base. The "vulnerability" and "hazard" were divided into five categories of "high", "medium-high", "medium", "low-medium" and "low", respectively. Then, "vulnerability" and "hazard" were firstly combined by integrated evaluation. Compared with the other two scenarios under deterministic methods, the risk obtained in the proposed system is higher. This research illustrated that ignoring of uncertainties in evaluation process might underestimate the risk level. 展开更多
关键词 integrated evaluation RANDOMNESS FUZZINESS modified health risk assessment uncertainty MANGANESE
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Multimedia health risk assessment:A case study of scenario-uncertainty 被引量:2
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作者 李飞 黄瑾辉 +3 位作者 曾光明 袁兴中 梁婕 王晓钰 《Journal of Central South University》 SCIE EI CAS 2012年第10期2901-2909,共9页
Assisted by framework of multimedia total exposure model for hazard waste sites(CalTOX),potential influences of scenario-uncertainty on multimedia health risk assessment(MHRA) and decision-making were quantitatively a... Assisted by framework of multimedia total exposure model for hazard waste sites(CalTOX),potential influences of scenario-uncertainty on multimedia health risk assessment(MHRA) and decision-making were quantitatively analyzed in a primary extent under the Chinese scenario case by deliberately varying the two key scenario-elements,namely conceptual exposure pathways combination and aim receptor cohorts choice.Results show that the independent change of one exposure pathway or receptor cohort could lead variation of MHRA results in the range of 3.6×10-6-1.4×10-5 or 6.7×10-6-2.3×10-5.And randomly simultaneous change of those two elements could lead variation of MHRA results at the range of 7.7×10-8-2.3×10-5.On the basis of the corresponding sensitivity analysis,pathways which made a valid contribution to the final modeling risk value occupied only 16.7% of all considered pathways.Afterwards,comparative analysis between influence of parameter-uncertainty and influence of scenario-uncertainty was made.In consideration of interrelationship among all types of uncertainties and financial reasonability during MHRA procedures,the integrated method how to optimize the entire procedures of MHRA was presented innovatively based on sensitivity analysis,scenario-discussion and nest Monte Carlo simulation or fuzzy mathematics. 展开更多
关键词 scenario-uncertainty multimedia health risk assessment (MHRA) comparative analysis parameter-uncertainty
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Risk Assessment of Maize Cold Damage in Heilongjiang Province in Recent 30 Years 被引量:1
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作者 Sun Yan-kun Yu Lan 《Journal of Northeast Agricultural University(English Edition)》 CAS 2018年第2期20-26,共7页
In order to make the relevant risk departments and the agricultural producers have a clearer understanding of maize cold damage, the data of daily average temperature of 83 meteorological stations in Heilongjiang Prov... In order to make the relevant risk departments and the agricultural producers have a clearer understanding of maize cold damage, the data of daily average temperature of 83 meteorological stations in Heilongjiang Province from 1986 to 2015, and the risk assessment model of maize cold damage in northeast China were used, and the risk index values of maize cold damage in Heilongjiang Province from 1986 to 2015 were calculated. And according to the risk index values, Heilongjiang Province was divided into five risk areas. The results showed that the high risk areas and the sub-high risk areas of maize cold damage in Heilongjiang Province in recent 30 years were in Daqing and Suihua cities, the medium risk areas were located in the center of the Songnen Plain and other regions, the sub-low risk areas were located in the Songnen Plain, and most of the rest were the low risk areas. 展开更多
关键词 maize cold damage risk assessment Heilongjiang Province
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Risk Assessment Framework and Algorithm of Power Systems Based on the Partitioned Multi-objective Risk Method 被引量:11
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作者 XIE Shaoyu WANG Xiuli WANG Xifan 《中国电机工程学报》 EI CSCD 北大核心 2011年第34期I0005-I0005,7,共1页
针对平均风险指标无法区分高损失-低概率事件及低损失-高概率事件的缺点,提出了电力系统的分割多目标风险分析框架。该框架将电力系统的风险状态细分为低损失、中等损失和高损失3个风险范围,并提出3个损失范围条件风险函数和条件风险概... 针对平均风险指标无法区分高损失-低概率事件及低损失-高概率事件的缺点,提出了电力系统的分割多目标风险分析框架。该框架将电力系统的风险状态细分为低损失、中等损失和高损失3个风险范围,并提出3个损失范围条件风险函数和条件风险概率的概念。采用经典的容量停运表模型,建立了这些条件期望指标的计算方法。对IEEE-RTS及TH-RTS2000系统进行了分割多目标风险评估,研究不同负荷水平下系统风险在3个损失范围的分布及转移情况,并分析损失分割点对系统风险的影响。通过分割多目标风险分析,风险分析者和决策者可以权衡系统的平均风险以及高、中、低损失范围的条件期望风险,从而对系统的风险状况有一个全面和深入的了解。 展开更多
关键词 英文摘要 内容介绍 编辑工作 期刊
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Russian and Foreign Experience Review of Territorial Geocryological Hazards Assessment and Risks of Geocryological Processes' Impact
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作者 J.V.Stanilovskaya 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期76-76,共1页
Hazards and risks assessment of dangerous geocryological processes is actual problem in connection with climate change.Permafrost is widespread in Russia,Canada,the USA(Alaska), China,Mongolia and in mountain regions.... Hazards and risks assessment of dangerous geocryological processes is actual problem in connection with climate change.Permafrost is widespread in Russia,Canada,the USA(Alaska), China,Mongolia and in mountain regions.Currently there are many papers concerning permafrost-related hazards,but the conceptual and based techniques are not available.Different approaches for solving this problem are considered in the paper.The generally accessible techniques of geocryological processes quantitative risk assessment are not available.The problem lies in uncertainty appearing from 展开更多
关键词 hazards and riskS assessment DANGEROUS geocryological processes PERMAFROST
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Review of Geocryological Hazards and Risks Assessment
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作者 J.V.Stanilovskaya D.O.Sergeev 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期65-65,共1页
Hazards and risks assessment of dangerous geocryological processes is an actual problem in connection with climate change.Permafrost is widespread in Russia,Canada,the USA(Alaska),China,Mongolia and in mountain region... Hazards and risks assessment of dangerous geocryological processes is an actual problem in connection with climate change.Permafrost is widespread in Russia,Canada,the USA(Alaska),China,Mongolia and in mountain regions.Currently there are many papers concerning permafrost-related hazards,but the conceptual and basic techniques are not available. Different approaches for solving this problem are considered in the paper.The generally accessible techniques of geocryological processes quantitative risk assessment are not available.The problem lies 展开更多
关键词 hazards and riskS assessment DANGEROUS geocryological PROCESSES PERMAFROST
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Non-parametric Statistical Analysis and Spatial Distribution of the Regional Geochemical Data of the Okiep Copper District,Namaqualand,South Africa:Implications for Anthropogenic Influence and Risk Assessment
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作者 Robert N.Hansen 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期69-69,共1页
The Okiep Copper District is the oldest mining district in South Africa with a legacy of more than 150 years of mining.This legacy can be felt in the presence of large tailings dams scattered throughout the area.These... The Okiep Copper District is the oldest mining district in South Africa with a legacy of more than 150 years of mining.This legacy can be felt in the presence of large tailings dams scattered throughout the area.These tailings have a deleterious impact on the surrounding environment.To use geochemical methods in determining the scale of the impact, pre-mining background levels need to be determined. This is especially difficult in areas for which 展开更多
关键词 statistical analysis METALS soil risk assessment
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Research on Market Risk Assessment of Dairy Farms: Taking 75 Dairy Farms in Heilongjiang Province as Examples
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作者 Li Yan-ling Li Cui-xia 《Journal of Northeast Agricultural University(English Edition)》 CAS 2018年第2期88-96,共9页
Based on the investigation and research on 75 dairy farms in Heilongjiang Province, evaluation index system of dairy farm market risk was set up, and dairy farm market risks were divided into pairing risk, price risk,... Based on the investigation and research on 75 dairy farms in Heilongjiang Province, evaluation index system of dairy farm market risk was set up, and dairy farm market risks were divided into pairing risk, price risk, production risk, contract risk and policy risk, five aspects of a total of 12 assessment indicators. The fuzzy comprehensive evaluation method was used to evaluate the market risk. The evaluation results showed that the market risk of dairy farms in Heilongjiang Province was at low risk; however, the policy risk was high. Finally, according to the results of the assessment, the suggestions was made as the followings: the government should expand the scope of policy insurance for dairy farming, vigorously promote the development of cooperative organizations and intermediary organizations in dairy farms by purchasing services through government, increase their functional roles and establish strict supervision mechanisms, including the establishment of official advice hotline and consultation channel online and improving third-party testing mechanism; government and the department of management industry would improve their abilities of management and do a good job of training and guiding. 展开更多
关键词 dairy farm market risk assessment fuzzy comprehensive evaluation
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Trace elements spatial distribution characteristics,risk assessment and potential source identification in surface water from Honghu Lake,China
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作者 LIU Chao-yang ZHANG Jing-dong +6 位作者 LI Fei) YANG Jun QIU Zhen-zhen CAI Ying ZHU Li-yun XIAO Min-si WU Zi-xian 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第7期1598-1611,共14页
Five trace elements including Zn, Cu, Cd, Cr and As were investigated in surface water from ten typical sampling sites in Honghu Lake. The consequence indicated that all of the detected trace element levels were withi... Five trace elements including Zn, Cu, Cd, Cr and As were investigated in surface water from ten typical sampling sites in Honghu Lake. The consequence indicated that all of the detected trace element levels were within the allowed standard of China’s safe water guideline. The hazard quotients (HQ) and the hazard index (HI) value levels of all the five heavy metals in all sampling sites did not exceed the acceptable risk limits of non-carcinogenic value through the selected assessment method. Pearson’s correlation analysis and principal component analysis (PCA) indicated that Zn and Cu mainly originated from the natural alluviation and non-point agricultural sources, whereas Cr and As were mainly derived from industrial effluents. Moreover, Cd mainly originated from both non-point agricultural and industrial pollution sources. In addition, cluster analysis (CA) implied that cluster 1 (including S3, S5, S6 and S10) was considered the set of high pollution sites and cluster 2 (including S4 and S9) was identified as the set of moderate pollution sites. 展开更多
关键词 spatial distribution characteristic risk assessment source identification trace elements Honghu Lake
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Meteoroid and Space Debris Risk Assessment for Satellites Orbiting the Earth/Moon
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作者 FENG Shuai WANG Ronglan 《空间科学学报》 CAS CSCD 北大核心 2023年第4期724-735,共12页
Interplanetary meteoroids and space debris can impact satellites orbiting the Earth or spacecraft traveling to the Moon.Targeting China Space Station(CSS),7 satellites selected from the constellation of Beidou Navigat... Interplanetary meteoroids and space debris can impact satellites orbiting the Earth or spacecraft traveling to the Moon.Targeting China Space Station(CSS),7 satellites selected from the constellation of Beidou Navigation Satellite System Phase III(BDS-3),and 3 spacecraft orbiting the Moon,we have adopted in the paper the Meteoroid Engineering Model 3,Divine-Staubach meteoroid environment model,and Jenniskens-McBride meteoroid steam model to analyze the meteoroid environment with the mass range of 10–6~10 g.Orbital Debris Engineering Model 3.1 space debris model is used to analyze the orbital debris environment faced by these satellites.The flux of space debris with a size larger than 100μm is compared with that of the meteoroids.The results show that the space debris flux encountered by China Space Station is much higher than that of the meteoroids with sizes in the above range.And quite the opposite,the meteoroids flux impacting the 7 satellites from the BDS-3 is higher.Upon adopting the double-layer Whipple protection measure,the catastrophic collision flux of these satellites encountering meteoroids is about 10–6 times of that without protection,or even less,implying that the Whipple protection effectively guarantees the safety of the satellites in orbit.Besides,it is also found that the flux of the high-density meteoroid population encountered by each satellite is greater than that of the low-density population,whereas the impact velocity is lower for each satellite.These results can aid the orbit selection and the protection design for satellites and spacecraft. 展开更多
关键词 Meteoroid environment model Space debris model Ballistic limit equation Impact risk assessment
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New development in risk assessment of genotoxic carcinogens in foods
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作者 Ian KIMBER 《中国药理学与毒理学杂志》 CAS CSCD 北大核心 2006年第3期161-162,共2页
The no-observed-effect level (NOEL) in a study of carcinogenicity for compounds that are both genotoxic and carcinogenic represents the limit of detection in that bioassay, rather than an estimate of a possible thresh... The no-observed-effect level (NOEL) in a study of carcinogenicity for compounds that are both genotoxic and carcinogenic represents the limit of detection in that bioassay, rather than an estimate of a possible threshold. Therefore, for those genotoxic and carcinogenic contaminants (e.g. acrylamides, PAHs, etc.) in foods it is not possible to develop health-based guidance values (e.g. ADI or PTWI) using the traditional NOEL and safety/uncertainty factors. 展开更多
关键词 New development in risk assessment of genotoxic carcinogens in foods
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