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Observation of the Effect of Video Assessment Method on the Operation Skills of Individual Nurses
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作者 Jianhua Qin Xiaolu Wan Nannan Ma 《Journal of Clinical and Nursing Research》 2024年第8期122-128,共7页
Objective:To explore the application effect of video assessment method in clinical nurses’nursing operation skills.Method:To select 58 nurses who participated in the individual soldier standard in the children’s hos... Objective:To explore the application effect of video assessment method in clinical nurses’nursing operation skills.Method:To select 58 nurses who participated in the individual soldier standard in the children’s hospital in 2019 and 2020 as the research objects,among which the nurses who participated in the individual soldier standard in 2019 were the nurses who participated in the individual soldier standard in 2019 and 2020.A total of 29 people in the first batch were set as the control group,using traditional assessment methods.In 2020,the second batch of 29 nurses who participated in the individual soldier standard reached the experimental group.Using the video assessment method,there was no significant difference in general information between the two groups(P>0.05).After the assessment,the scores,coping with work pressure,and proactiveness of the two groups of research subjects were compared.Results:The experimental group’s nursing operation assessment scores,coping with work pressure,and proactiveness were significantly better than those of the control group,the difference was statistically significant(P<0.05).Conclusion:The application of the video assessment method improves the passing rate of nurses’operational skills examination,enhances nurses’initiative in learning,reduces examination pressure,and can be accurately,timely,and safely applied to clinical nursing work,which is worthy of study and promotion. 展开更多
关键词 Video assessment method NURSE Operation skills Effect observation
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A novel refined dynamic model of high-speed maglev train-bridge coupled system for random vibration and running safety assessment
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作者 MAO Jian-feng LI Dao-hang +3 位作者 YU Zhi-wu CAI Wen-feng GUO Wei ZHANG Guang-wen 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2532-2544,共13页
Running safety assessment and tracking irregularity parametric sensitivity analysis of high-speed maglev train-bridge system are of great concern,especially need perfect refinement models in which all properties can b... Running safety assessment and tracking irregularity parametric sensitivity analysis of high-speed maglev train-bridge system are of great concern,especially need perfect refinement models in which all properties can be well characterized based on various stochastic excitations.A three-dimensional refined spatial random vibration analysis model of high-speed maglev train-bridge coupled system is established in this paper,in which multi-source uncertainty excitation can be considered simultaneously,and the probability density evolution method(PDEM)is adopted to reveal the system-specific uncertainty dynamic characteristic.The motion equation of the maglev vehicle model is composed of multi-rigid bodies with a total 210-degrees of freedom for each vehicle,and a refined electromagnetic force-air gap model is used to account for the interaction and coupling effect between the moving train and track beam bridges,which are directly established by using finite element method.The model is proven to be applicable by comparing with Monte Carlo simulation.By applying the proposed stochastic framework to the high maglev line,the random dynamic responses of maglev vehicles running on the bridges are studied for running safety and stability assessment.Moreover,the effects of track irregularity wavelength range under different amplitude and running speeds on the coupled system are investigated.The results show that the augmentation of train speed will move backward the sensitive wavelength interval,and track irregularity amplitude influences the response remarkably in the sensitive interval. 展开更多
关键词 maglev train-bridge interaction electromagnetic force-air gap model stochastic dynamic analysis running safety assessment probability density evolution method
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Seismic safety assessment with non-Gaussian random processes for train-bridge coupled systems
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作者 Zhao Han Gao Lei +4 位作者 Wei Biao Tan Jincheng Guo Peidong Jiang Lizhong Xiang Ping 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第1期241-260,共20页
Extensive high-speed railway(HSR)network resembled the intricate vascular system of the human body,crisscrossing mainlands.Seismic events,known for their unpredictability,pose a significant threat to both trains and b... Extensive high-speed railway(HSR)network resembled the intricate vascular system of the human body,crisscrossing mainlands.Seismic events,known for their unpredictability,pose a significant threat to both trains and bridges,given the HSR’s extended operational duration.Therefore,ensuring the running safety of train-bridge coupled(TBC)system,primarily composed of simply supported beam bridges,is paramount.Traditional methods like the Monte Carlo method fall short in analyzing this intricate system efficiently.Instead,efficient algorithm like the new point estimate method combined with moment expansion approximation(NPEM-MEA)is applied to study random responses of numerical simulation TBC systems.Validation of the NPEM-MEA’s feasibility is conducted using the Monte Carlo method.Comparative analysis confirms the accuracy and efficiency of the method,with a recommended truncation order of four to six for the NPEM-MEA.Additionally,the influences of seismic magnitude and epicentral distance are discussed based on the random dynamic responses in the TBC system.This methodology not only facilitates seismic safety assessments for TBC systems but also contributes to standard-setting for these systems under earthquake conditions. 展开更多
关键词 train-bridge coupled(TBC)system random vibration new point estimate method(NPEM) seismic safety assessment moment expansion approximation(MEA) non-Gaussian distributions
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Research on the Reform of Assessment under the Blended Teaching Mode:Taking the Teaching Practice of English Stylistics in Guangdong Technology College as an Example
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作者 Jie Zhang 《Journal of Contemporary Educational Research》 2024年第11期145-152,共8页
English Stylistics is provided as an elective course by the Business English major at Guangdong Technology College,whose evaluation mechanism significantly impacts how well students learn the language.A novel assessme... English Stylistics is provided as an elective course by the Business English major at Guangdong Technology College,whose evaluation mechanism significantly impacts how well students learn the language.A novel assessment model is put forth in this study with the intention of transforming from a single summative assessment to a combination of formative and summative assessment in light of the shortcomings of the current assessment methodology in the course.In order to take advantage of blended teaching and integrate the online and offline learning resources of English Stylistics,all-round reforms have been carried out at multiple levels,including teaching content,teaching methods,and assessment approaches.Therefore,a more reasonable and diversified assessment method has been adopted to more comprehensively reflect students’learning objectives and proficiency in foreign languages. 展开更多
关键词 Blended teaching assessment method English Stylistics
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Comparative Analysis of Pythagorean MCDM Methods for the Risk Assessment of Childhood Cancer
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作者 Shaista Habib Muhammad Akram MMAli Al-Shamiri 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第6期2585-2615,共31页
According to the World Health Organization(WHO),cancer is the leading cause of death for children in low and middle-income countries.Around 400,000 kids get diagnosed with this illness each year,and their survival rat... According to the World Health Organization(WHO),cancer is the leading cause of death for children in low and middle-income countries.Around 400,000 kids get diagnosed with this illness each year,and their survival rate depends on the country in which they live.In this article,we present a Pythagorean fuzzy model that may help doctors identify the most likely type of cancer in children at an early stage by taking into account the symptoms of different types of cancer.The Pythagorean fuzzy decision-making techniques that we utilize are Pythagorean Fuzzy TOPSIS,Pythagorean Fuzzy Entropy(PF-Entropy),and Pythagorean Fuzzy PowerWeighted Geometric(PFPWG).Ourmodel is fed with nineteen symptoms and it diagnoses the risk of eight types of cancers in children.We develop an algorithm for each method and calculate its complexity.Additionally,we consider an example to make a clear understanding of our model.We also compare the final results of various tests that prove the authenticity of this study. 展开更多
关键词 Risk assessment Pythagorean fuzzy sets TOPSIS method ENTROPY power weighted geometric operators
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Risk Assessment of Diary Cattle Brucellosis Based on Systematic Multilevel Grey Relation Entropy Method
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作者 孙向东 江慎铭 刘拥军 《Agricultural Science & Technology》 CAS 2012年第10期2169-2174,2225,共7页
[Objective] The study was to explore the major factors affecting diary cattle brucellosis risk assessment,as well as their strong-to-weak sequence,so as to provide theoretical basis for assessing diary cattle brucello... [Objective] The study was to explore the major factors affecting diary cattle brucellosis risk assessment,as well as their strong-to-weak sequence,so as to provide theoretical basis for assessing diary cattle brucellosis risk level in different regions.[Method] From 4 dimensions of feeding and importing,breeding,housing and polyculture situation,an evaluation index system was set up,and diary cattle brucellosis risk survey was conducted in 3 typical regions.Finally,systematic multilevel grey relation entropy method was applied to perform data analysis.[Result] The strong-to-weak sequence of Level 1 impact factor of diary cattle brucellosis was as follows:feeding and importinghousingpolyculture situationbreeding;the sequence of Level 2 impact factor was U32〉U12〉U11〉U31〉U21〉U42〉U43〉U23〉U22〉U41;the risk level sequence of 3 typical regions was Province A(County A1,A2,A3)Province B(County B1,B2,B3)Province C(County C1,C2,C3).[Conclusion] According to the weight of Level 1 index strata,administrative departments at all levels and dairy cattle farmers should lay emphasis on the aspects of feeding,importing and housing;viewed from the perspective of Level 2 index strata,dairy cattle farmers should value the siting of cattle field,the brucellosis surveillance before importing and milking modes most.According to the diary cattle brucellosis risk level of 3 typical regions,if administrative departments at all levels strengthen peoples' awareness of their personal health and increase investment in this area,with new healthy cultured atmosphere built,the risk level of diary cattle brucellosis will surly decline. 展开更多
关键词 Systematic multilevel grey relation entropy method Diary cattle brucellosis Risk assessment
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Urban flood risk assessment under rapid urbanization in Zhengzhou City,China 被引量:2
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作者 LI Guoyi LIU Jiahong SHAO Weiwei 《Regional Sustainability》 2023年第3期332-348,共17页
With accelerated urbanization and climate change,urban flooding is becoming more and more serious.Flood risk assessment is an important task for flood management,so it is crucial to map the spatial and temporal distri... With accelerated urbanization and climate change,urban flooding is becoming more and more serious.Flood risk assessment is an important task for flood management,so it is crucial to map the spatial and temporal distribution of flood risk.This paper proposed an urban flood risk assessment method that takes into account the influences of hazard,vulnerability,and exposure,by constructing a multi-index urban flood risk assessment framework based on Geographic Information System(GIS).To determine the weight values of urban flood risk index factors,we used the analytic hierarchy process(AHP).Also,we plotted the temporal and spatial distribution maps of flood risk in Zhengzhou City in 2000,2005,2010,2015,and 2020.The analysis results showed that,the proportion of very high and high flood risk zone in Zhengzhou City was 1.362%,5.270%,4.936%,12.151%,and 24.236%in 2000,2005,2010,2015,and 2020,respectively.It is observed that the area of high flood risk zones in Zhengzhou City showed a trend of increasing and expanding,of which Dengfeng City,Xinzheng City,Xinmi City,and Zhongmu County had the fastest growth rate and the most obvious increase.The flood risk of Zhengzhou City has been expanding with the development of urbanization.The method is adapted to Zhengzhou City and will have good adaptability in other research areas,and its risk assessment results can provide a scientific reference for urban flood management personnel.In the future,the accuracy of flood risk assessment can be further improved by promoting the accuracy of basic data and reasonably determining the weight values of index factors.The risk zoning map can better reflect the risk distribution and provide a scientific basis for early warning of flood prevention and drainage. 展开更多
关键词 Urban flood Flood risk assessment Geographic Information System(GIS) Multi-index system method URBANIZATION Zhengzhou City
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Prioritizing real estate enterprises based on credit risk assessment:an integrated multi‑criteria group decision support framework 被引量:1
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作者 Zhen‑Song Chen Jia Zhou +5 位作者 Chen‑Ye Zhu Zhu‑Jun Wang Sheng‑Hua Xiong Rosa M.Rodríguez Luis Martínez Mirosław J.Skibniewski 《Financial Innovation》 2023年第1期2939-2991,共53页
Credit risk assessment involves conducting a fair review and evaluation of an assessed subject’s solvency and creditworthiness.In the context of real estate enterprises,credit risk assessment provides a basis for ban... Credit risk assessment involves conducting a fair review and evaluation of an assessed subject’s solvency and creditworthiness.In the context of real estate enterprises,credit risk assessment provides a basis for banks and other financial institutions to choose suitable investment objects.Additionally,it encourages real estate enterprises to abide by market norms and provide reliable information for the standardized management of the real estate industry.However,Chinese real estate companies are hesitant to disclose their actual operating data due to privacy concerns,making subjective evalu-ation approaches inevitable,occupying important roles in accomplishing Chinese real estate enterprise credit risk assessment tasks.To improve the normative and reliability of credit risk assessment for Chinese real estate enterprises,this study proposes an integrated multi-criteria group decision-making approach.First,a credit risk assessment index for Chinese real estate enterprises is established.Then,the proposed framework combines proportional hesitant fuzzy linguistic term sets and preference ranking organization method for enrichment evaluation II methods.This approach is suitable for processing large amounts of data with high uncertainty,which is often the case in credit risk assessment tasks of Chinese real estate enterprises involving massive subjec-tive evaluation information.Finally,the proposed model is validated through a case study accompanied by sensitivity and comparative analyses to verify its rationality and feasibility.This study contributes to the research on credit assessment for Chinese real estate enterprises and provides a revised paradigm for real estate enterprise credit risk assessment. 展开更多
关键词 Real estate enterprise Credit risk assessment PROMETHEE II Best–worst method Proportional hesitant fuzzy linguistic term sets
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A Comparative Analysis of Environmental Quality Assessment Methods for Heavy Metal-Contaminated Soils 被引量:33
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作者 LI Wei-Xin ZHANG Xu-Xiang +5 位作者 WU Bing SUN Shi-Lei CHEN Yan-Song PAN Wen-Yang ZHAO Da-Yong CHENG Shu-Pei 《Pedosphere》 SCIE CAS CSCD 2008年第3期344-352,共9页
Four assessment methods (two pollution indexes and two fuzzy mathematical models) were employed to investigate the environmental quality of four soils around a ferroalloy plant in Nanjing City. Environmental quality... Four assessment methods (two pollution indexes and two fuzzy mathematical models) were employed to investigate the environmental quality of four soils around a ferroalloy plant in Nanjing City. Environmental quality was assessed as class Ⅳ (moderately polluted) for each soil with single-factor index method, and was identified to be classes Ⅳ, Ⅲ (slightly polluted), Ⅲ, and Ⅲ for soils A, B, C, and D, respectively, with the comprehensive index model. In comparison with the single-factor index method, the comprehensive index model concerned both dominant parameter and average contribution of all factors to the integrated environmental quality. Using the two fuzzy mathematical methods (single-factor deciding and weighted average models), the environmental risks were determined to be classes Ⅳ, Ⅲ, Ⅱ (clean), and Ⅱ for soils A, B, C, and D, respectively. However, divergence of the membership degree to each pollution class still occurred between the two methods. In fuzzy mathematical methods, membership functions were used to describe the limits between different pollution degrees, and different weights were allocated for the factors according to pollution contribution. Introduction of membership degree and weight of each factor to fuzzy mathematical models made the methods more reasonable in the field of environmental risk assessment. 展开更多
关键词 environmental assessment fuzzy mathematical model heavy metal pollution pollution index method SOIL
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Dynamic assessment method of air target threat based on improved GIFSS 被引量:9
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作者 FENG Jinfu ZHANG Qiang +1 位作者 HU Junhua LIU An 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第3期525-534,共10页
As the air combat environment becomes more complicated and changeable, accurate threat assessment of air target has a significant impact on air defense operations. This paper proposes an improved generalized intuition... As the air combat environment becomes more complicated and changeable, accurate threat assessment of air target has a significant impact on air defense operations. This paper proposes an improved generalized intuitionistic fuzzy soft set (GIFSS) method for dynamic assessment of air target threat. Firstly, the threat assessment index is reasonably determined by analyzing the typical characteristics of air targets. Secondly, after the GIFSS at different time is obtained, the index weight is determined by the intuitionistic fuzzy set entropy and the relative entropy theory. Then, the inverse Poisson distribution method is used to determine the weight of time series, and then the time-weighted GIFSS is obtained. Finally, threat assessment of five air targets is carried out by using the improved GIFSS (I-GIFSS) and comparison methods. The validity and superiority of the proposed method are verified by calculation and comparison. 展开更多
关键词 THREAT DYNAMIC assessment generalized intuitionistic FUZZY soft set (GIFSS) intuitionistic FUZZY ENTROPY RELATIVE ENTROPY inverse POISSON distribution method
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STUDY ON METHOD OF QUANTITATIVE ASSESSMENT OF FRAGILE ENVIRONMENT 被引量:2
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作者 赵跃龙 张玲娟 《Chinese Geographical Science》 SCIE CSCD 1999年第2期45-49,共5页
Todaysustainabledevelopmentiscurentlypromoted,butprohibitedbyfragileenvironment.Soinrecentyears,thestudyinc... Todaysustainabledevelopmentiscurentlypromoted,butprohibitedbyfragileenvironment.Soinrecentyears,thestudyincludingformationre... 展开更多
关键词 fragile ECO ENVIRONMENT QUANTITATIVE assessment INDEX method
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Seismic assessment of unanchored steel storage tanks by endurance time method 被引量:4
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作者 M. Alembagheri H.E. Estekanchi 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2011年第4期591-603,共13页
Liquid storage tanks are essential structures that are often located in residential and industrial areas; thus an assessment of their seismic performance is an important engineering issue. In this paper, the seismic r... Liquid storage tanks are essential structures that are often located in residential and industrial areas; thus an assessment of their seismic performance is an important engineering issue. In this paper, the seismic response ofunanchored steel liquid storage tanks is investigated using the endurance time (ET) dynamic analysis procedure and compared to responses obtained for anchored tanks under actual ground motions and intensifying ET records. In most cases, the results from ground motions are properly obtained with negligible differences using ET records. It is observed that uplifting of the tank base, which is closely related to the tank aspect ratio, has the greatest significance in the responses of the tank and can be predicted with reasonable accuracy by using currently available ET records. 展开更多
关键词 steel liquid storage tanks endurance time method seismic assessment intensifying dynamic excitation tank base uplifting
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Research Progress in Occupational Health Risk Assessment Methods in China 被引量:23
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作者 ZHOU Li Fang TIAN Fang +3 位作者 ZOU Hua YUAN Wei Ming HAO Mo ZHANG Mei Bian 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2017年第8期616-622,共7页
Traditional occupational disease control and prevention has remained prevalent in China over recent decades. There are appropriately 30,000 new case reports of occupational diseases annually. Although China has alread... Traditional occupational disease control and prevention has remained prevalent in China over recent decades. There are appropriately 30,000 new case reports of occupational diseases annually. Although China has already established a series of occupational disease prevention programs, occupational health risk assessment (OHRA) strategies continue to be a limitation. 展开更多
关键词 HR Research Progress in Occupational Health Risk assessment methods in China
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A RISK ASSESSMENT METHOD OF THE WIRELESS NETWORK SECURITY 被引量:13
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作者 Zhao Dongmei Wang Changguang Ma Jianfeng 《Journal of Electronics(China)》 2007年第3期428-432,共5页
The core of network security is the risk assessment. In this letter,a risk assessment method is introduced to estimate the wireless network security. The method,which combines Analytic Hier-archy Process (AHP) method ... The core of network security is the risk assessment. In this letter,a risk assessment method is introduced to estimate the wireless network security. The method,which combines Analytic Hier-archy Process (AHP) method and fuzzy logical method,is applied to the risk assessment. Fuzzy logical method is applied to judge the important degree of each factor in the aspects of the probability,the influence and the uncontrollability,not to directly judge the important degree itself. The risk as-sessment is carved up 3 layers applying AHP method,the sort weight of the third layer is calculated by fuzzy logical method. Finally,the important degree is calculated by AHP method. By comparing the important degree of each factor,the risk which can be controlled by taking measures is known. The study of the case shows that the method can be easily used to the risk assessment of the wireless network security and its results conform to the actual situation. 展开更多
关键词 Wireless network Risk assessment Analytic Hierarchy Process (AHP) method Fuzzy logical method
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Application of a Bayesian method to data-poor stock assessment by using Indian Ocean albacore (Thunnus alalunga) stock assessment as an example 被引量:14
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作者 GUAN Wenjiang TANG Lin +2 位作者 ZHU Jiangfeng TIAN Siquan XU Liuxiong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第2期117-125,共9页
It is widely recognized that assessments of the status of data-poor fish stocks are challenging and that Bayesian analysis is one of the methods which can be used to improve the reliability of stock assessments in dat... It is widely recognized that assessments of the status of data-poor fish stocks are challenging and that Bayesian analysis is one of the methods which can be used to improve the reliability of stock assessments in data-poor situations through borrowing strength from prior information deduced from species with good-quality data or other known information. Because there is considerable uncertainty remaining in the stock assessment of albacore tuna(Thunnus alalunga) in the Indian Ocean due to the limited and low-quality data, we investigate the advantages of a Bayesian method in data-poor stock assessment by using Indian Ocean albacore stock assessment as an example. Eight Bayesian biomass dynamics models with different prior assumptions and catch data series were developed to assess the stock. The results show(1) the rationality of choice of catch data series and assumption of parameters could be enhanced by analyzing the posterior distribution of the parameters;(2) the reliability of the stock assessment could be improved by using demographic methods to construct a prior for the intrinsic rate of increase(r). Because we can make use of more information to improve the rationality of parameter estimation and the reliability of the stock assessment compared with traditional statistical methods by incorporating any available knowledge into the informative priors and analyzing the posterior distribution based on Bayesian framework in data-poor situations, we suggest that the Bayesian method should be an alternative method to be applied in data-poor species stock assessment, such as Indian Ocean albacore. 展开更多
关键词 data-poor stock assessment Bayesian method catch data series demographic method Indian Ocean Thunnus alalunga
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PRELIMINARY STUDY OF THE ASSESSMENT OF METHODS FOR DISASTER-INDUCING RISKS BY TCs USING SAMPLE EVENTS OF TCs THAT AFFECTED SHANGHAI 被引量:5
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作者 杨秋珍 徐明 《Journal of Tropical Meteorology》 SCIE 2010年第3期299-304,共6页
Hazard factors, hazard-bearling objects, disaster-developing environment, and disaster-preventing capability play key roles in the formation of Tropical Cyclone (TC) disasters. Of all of these, the most important is... Hazard factors, hazard-bearling objects, disaster-developing environment, and disaster-preventing capability play key roles in the formation of Tropical Cyclone (TC) disasters. Of all of these, the most important is the intensity of hazard factors (risk sources). In this study, this intensity is uniformly defined by the probability of hazard factors; then a relationship is established between disaster risk intensity and hazard factors. The exceedance probability of various hazard factors, including frequency and timing, scope of wind and rain, and maximum wind and rain of impacting TC cases, are calculated using data from TCs that impacted Shanghai fi'om 1959-2006. The relationship between disaster situation and risk probability of hazard factors is analyzed, and the indices and model of TC disaster assessment are established based on the results. The process maximum wind speed and maximum daily precipitation are very important in TC-related disaster formation in Shanghai. The results of disaster indices coordinate with the results of the assessment model, and both can show the extent of probability of a TC disaster. Tests using TC data in 2007 and 2008 show that disasters caused by TC Krosa (0716) would be more serious than those by TC Wipha (0713), and that TC Fung Wong (0808) would have a weak impact. Real-life situations validate these results. 展开更多
关键词 TCS disaster risk assessment methods
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Discussion on the Assessment Method of Wind Energy Resources by Using Regional Meteorological Data 被引量:4
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作者 HE Jie-yan DAI Yu +3 位作者 JIN Xuan-xi LV Xiao-hua WANG Wei-nong LIU Cong-sheng 《Meteorological and Environmental Research》 CAS 2011年第2期10-12,17,共4页
The exploitation status of wind energy resources was analyzed, and the distribution of wind energy resources and regional meteorological stations were introduced, and then the assessment method of wind energy resource... The exploitation status of wind energy resources was analyzed, and the distribution of wind energy resources and regional meteorological stations were introduced, and then the assessment method of wind energy resources by using data from regional meteorological station was studied taking Huangjin Regional Meteorological Station in Xinning County in Hunan Province for example, besides, corresponding software was compiled. By means of SQL database and program, the method was used simply and easily and had positive meaning for the development of wind energy resources and excavation of wind farm in inland region. 展开更多
关键词 Regional meteorological station Wind energy resources assessment method China
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Analytical Methods for Environmental Risk Assessment of Acid Sulfate Soils: A Review 被引量:5
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作者 C. LIN School of Environmental Science and Management, Southern Cross University, Lismore, NSW (Australia) 《Pedosphere》 SCIE CAS CSCD 2001年第4期301-310,共10页
Assessment of acid sulfate soil risk is an important step for acid sulfate soil management and its reliability depends very much on the suitability and accuracy of various analytical methods for estimating sulfide-der... Assessment of acid sulfate soil risk is an important step for acid sulfate soil management and its reliability depends very much on the suitability and accuracy of various analytical methods for estimating sulfide-derived potential acidity, actual acidity and acid-neutralizing capacity in acid sulfate soils. This paper critically reviews various analytical methods that are currently used for determination of the above parameters, as well as their implications for environmental risk assessment of acid sulfate soi1s. 展开更多
关键词 acid risk assessment acid sulfate soils analytical methods
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Fatigue Assessment Method for Composite Wind Turbine Blade 被引量:2
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作者 Chen Cheng Wang Tongguang 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2016年第1期102-111,共10页
Fatigue strength assessment of a horizontal axis wind turbine(HAWT)composite blade is considered.Fatigue load cases are identified,and loads are calculated by the GH Bladed software which is specified at the IEC61400 ... Fatigue strength assessment of a horizontal axis wind turbine(HAWT)composite blade is considered.Fatigue load cases are identified,and loads are calculated by the GH Bladed software which is specified at the IEC61400 international specification and GL(Germanisher Lloyd)regulations for the wind energy conversion system.Stress analysis is performed with a 3-D finite element method(FEM).Considering Saint-Venant′s principle,a uniform cross section FEM model is built at each critical zone.Stress transformation matrixes(STM)are set up by applied six unit load components on the FEM model separately.STM can be used to convert the external load into stresses in the linear elastic range.The main material of composite wind turbine blade is fiber reinforced plastics(FRP).In order to evaluate the degree of fatigue damage of FRP,the stresses of fiber direction are extracted and the well-known strength criterion-Puck theory is used.The total fatigue damage of each laminate on the critical point is counted by the rain-flow counting method and Miner′s damage law based on general S-N curves.Several sections of a 45.3mblade of a 2 MW wind turbine are studied using the fatigue evaluation method.The performance of this method is compared with far more costly business software FOCUS.The results show that the fatigue damage of multi-axis FRP can be assessed conveniently by the FEM-STM method.And the proposed method gives a reliable and efficient method to analyze the fatigue damage of slender composite structure with variable cross-sections. 展开更多
关键词 fatigue assessment wind turbine blade finite element method(FEM) stress transformation matrix
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Monte-Carlo Method for Coalbed Methane Resource Assessment in Key Coal Mining Areas of China 被引量:2
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作者 杨永国 陈玉华 +1 位作者 秦勇 成秋明 《Journal of China University of Geosciences》 SCIE CSCD 2008年第4期429-435,共7页
Monte-Carlo method is used for estimating coalbed methane (CBM) resources in key coal mining areas of China. Monte-Carlo method is shown to be superior to the traditional volumetric method with constant parameters i... Monte-Carlo method is used for estimating coalbed methane (CBM) resources in key coal mining areas of China. Monte-Carlo method is shown to be superior to the traditional volumetric method with constant parameters in the calculation of CBM resources. The focus of the article is to introduce the main algorithm and the realization of functions estimated by Monte-Carlo method, including selection of parameters, determination of distribution function, generation of pseudo-random numbers, and evaluation of the parameters corresponding to pseudo-random numbers. A specified software on the basis of Monte-Carlo method is developed using Visual C++ for the assessment of the CBM resources. A case study shows that calculation results using Monte-Carlo method have smaller error range in comparison with those using volumetric method. 展开更多
关键词 Monte-Carlo method CBM resource assessment algorithm realization key coal mining areas of China
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