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Comparative study of different machine learning models in landslide susceptibility assessment: A case study of Conghua District, Guangzhou, China
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作者 Ao Zhang Xin-wen Zhao +8 位作者 Xing-yuezi Zhao Xiao-zhan Zheng Min Zeng Xuan Huang Pan Wu Tuo Jiang Shi-chang Wang Jun He Yi-yong Li 《China Geology》 CAS CSCD 2024年第1期104-115,共12页
Machine learning is currently one of the research hotspots in the field of landslide prediction.To clarify and evaluate the differences in characteristics and prediction effects of different machine learning models,Co... Machine learning is currently one of the research hotspots in the field of landslide prediction.To clarify and evaluate the differences in characteristics and prediction effects of different machine learning models,Conghua District,which is the most prone to landslide disasters in Guangzhou,was selected for landslide susceptibility evaluation.The evaluation factors were selected by using correlation analysis and variance expansion factor method.Applying four machine learning methods namely Logistic Regression(LR),Random Forest(RF),Support Vector Machines(SVM),and Extreme Gradient Boosting(XGB),landslide models were constructed.Comparative analysis and evaluation of the model were conducted through statistical indices and receiver operating characteristic(ROC)curves.The results showed that LR,RF,SVM,and XGB models have good predictive performance for landslide susceptibility,with the area under curve(AUC)values of 0.752,0.965,0.996,and 0.998,respectively.XGB model had the highest predictive ability,followed by RF model,SVM model,and LR model.The frequency ratio(FR)accuracy of LR,RF,SVM,and XGB models was 0.775,0.842,0.759,and 0.822,respectively.RF and XGB models were superior to LR and SVM models,indicating that the integrated algorithm has better predictive ability than a single classification algorithm in regional landslide classification problems. 展开更多
关键词 Landslides susceptibility assessment Machine learning Logistic Regression Random Forest Support Vector Machines XGBoost assessment model Geological disaster investigation and prevention engineering
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A risk assessment method considering risk attributes and work safety informational needs and its application
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作者 Cong Luo Yunsheng Zhao Ke Xu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第4期253-262,共10页
The technological revolution has spawned a new generation of industrial systems,but it has also put forward higher requirements for safety management accuracy,timeliness,and systematicness.Risk assessment needs to evo... The technological revolution has spawned a new generation of industrial systems,but it has also put forward higher requirements for safety management accuracy,timeliness,and systematicness.Risk assessment needs to evolve to address the existing and future challenges by considering the new demands and advancements in safety management.The study aims to propose a systematic and comprehensive risk assessment method to meet the needs of process system safety management.The methodology first incorporates possibility,severity,and dynamicity(PSD)to structure the“51X”evaluation indicator system,including the inherent,management,and disturbance risk factors.Subsequently,the four-tier(risk point-unit-enterprise-region)risk assessment(RA)mathematical model has been established to consider supervision needs.And in conclusion,the application of the PSD-RA method in ammonia refrigeration workshop cases and safety risk monitoring systems is presented to illustrate the feasibility and effectiveness of the proposed PSD-RA method in safety management.The findings show that the PSD-RA method can be well integrated with the needs of safety work informatization,which is also helpful for implementing the enterprise's safety work responsibility and the government's safety supervision responsibility. 展开更多
关键词 Risk assessment Safey “51X”evaluation indicator system Four-tier risk assessment model Risk attributes Process system
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Towards Automated Assessment of Learning Management Systems in Higher Education Institutions in Zambia
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作者 Memory Mumbi Mayumbo Nyirenda 《Open Journal of Applied Sciences》 2024年第5期1279-1294,共16页
Zambia like any other country in most African regions is still grappling with the dynamics of harnessing technology for the betterment of Higher Education. The onset of the Covid 19 pandemic brought a test for the pre... Zambia like any other country in most African regions is still grappling with the dynamics of harnessing technology for the betterment of Higher Education. The onset of the Covid 19 pandemic brought a test for the preparedness of the Zambian Higher Education Institutions (HEIs) in harnessing technology for pedagogical activities. As countries worldwide switched to electronic learning during the pandemic, the same could not be said for Zambian HEIs. Zambian HEIs struggled to conduct pedagogical activities on learning management platforms. This study investigated the factors affecting the implementation and assessment of learning Management systems in Zambia’s HEIs. With its focus on assessing: 1) system features, 2) compliance with regulatory standards, 3) quality of service and 4) technology acceptance as the four key assessment areas of an LMS, this article proposed a model for assessing learning management systems in Zambian HEIs. To test the proposed model, a software tool was also developed. 展开更多
关键词 Learning Management Systems assessment Model Technology Acceptance Education Technology
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Research on the Assessment System of Computational Mechanics Courses Based on the TOPSIS Entropy Weight Model
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作者 Huijun Ning Ruhuan Yu +1 位作者 Qianshu Wang Mingming Lin 《Journal of Contemporary Educational Research》 2024年第6期166-182,共17页
This paper takes the assessment and evaluation of computational mechanics course as the background,and constructs a diversified course evaluation system that is student-centered and integrates both quantitative and qu... This paper takes the assessment and evaluation of computational mechanics course as the background,and constructs a diversified course evaluation system that is student-centered and integrates both quantitative and qualitative evaluation methods.The system not only pays attention to students’practical operation and theoretical knowledge mastery but also puts special emphasis on the cultivation of students’innovative abilities.In order to realize a comprehensive and objective evaluation,the assessment and evaluation method of the entropy weight model combining TOPSIS(Technique for Order Preference by Similarity to Ideal Solution)multi-attribute decision analysis and entropy weight theory is adopted,and its validity and practicability are verified through example analysis.This method can not only comprehensively and objectively evaluate students’learning outcomes,but also provide a scientific decision-making basis for curriculum teaching reform.The implementation of this diversified course evaluation system can better reflect the comprehensive ability of students and promote the continuous improvement of teaching quality. 展开更多
关键词 TOPSIS entropy weight model Computational mechanics Course assessment and evaluation system assessment model
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The Agricultural Assessment of Climatic Resource and Modeling in Jianghan Plain-Lake District 被引量:1
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作者 WANG Xue lei 1, WU Yi jin 2, LIU Gong hu 1 1. Institute of Geodesy & Geophysics, Chinese Academy of Sciences, Wuhan 430077, China 2. Department of History, University of Wuhan, Wuhan 430077, China 《Wuhan University Journal of Natural Sciences》 CAS 1999年第4期423-427,共5页
The feature of the climatic resource and the agricultural assessment in Jianghan plain lake district are discussed. In order to exploit the climatic resource, we have recommended some three dimensional agriculture de... The feature of the climatic resource and the agricultural assessment in Jianghan plain lake district are discussed. In order to exploit the climatic resource, we have recommended some three dimensional agriculture development models in this region according to the types of land use, such as paddy field ecological zone, dry land ecological zone, outskirts ecological zone of the city, waterbody ecological zone, woodland ecological zone. 展开更多
关键词 Jianghan plain climatic resource assessment modeling
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Modeling dynamic assessment of ecosystem services based on remote sensing technology:A sampling of the Gansu grassland ecosystem 被引量:1
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作者 Jian Wang ZhengHua Chen 《Research in Cold and Arid Regions》 2010年第6期514-521,共8页
关键词 ecosystem services value dynamic assessing model remote sensing CASA BIOMASS price index
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Human-Centric Composite-Quality Modeling and Assessment for Virtual Desktop Clouds
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作者 Yingxiao Xu Prasad Calyam +3 位作者 David Welling Saravanan Mohan Alex Berryman Rajiv Ramnath 《ZTE Communications》 2013年第1期27-36,共10页
There are several motivations, such as mobility, cost, and secu- rity, that are behind the trend of traditional desktop users transi- tioning to thin-client-based virtual desktop clouds (VDCs). Such a trend has led ... There are several motivations, such as mobility, cost, and secu- rity, that are behind the trend of traditional desktop users transi- tioning to thin-client-based virtual desktop clouds (VDCs). Such a trend has led to the rising importance of human-centric performance modeling and assessment within user communities that are increasingly making use of desktop virtualization. In this paper, we present a novel reference architecture and its eas- ily deployable implementation for modeling and assessing objec- tive user quality of experience (QoE) in VDCs. This architec- ture eliminates the need for expensive, time-consuming subjec- tive testing and incorporates finite-state machine representa- tions for user workload generation. It also incorporates slow-mo- tion benchmarking with deep-packet inspection of application task performance affected by QoS variations. In this way, a "composite-quality" metric model of user QoE can be derived. We show how this metric can be customized to a particular user group profile with different application sets and can be used to a) identify dominant performance indicators and troubleshoot bottlenecks and b) obtain both absolute and relative objective user QoE measurements needed for pertinent selection of thin-client encoding configurations in VDCs. We validate our composite-quality modeling and assessment methodology by us- ing subjective and objective user QoE measurements in a re- al-world VDC called VDPilot, which uses RDP and PCoIP thin-client protocols. In our case study, actual users are pres- ent in virtual classrooms within a regional federated university system. 展开更多
关键词 virtual desktops quality modeling and assessment performancebenchmarking thin-client protocol adaptation objective QoEmetrics
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Diamond Modeling in World Lithium Brine Utilization Assessment
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作者 WU Xishun HUANG Wenbin +2 位作者 YANG Tiantian SUN Zhangtao LI Li 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期267-268,共2页
The global transition away from hydrocarbons toward energy alternatives increases demand for many scarce metals.Among these is lithium,a key component of lithium-ion batteries for electric and hybrid vehicles.
关键词 diamond modeling lithium brine resources assessment
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Runoff Modeling in Ungauged Catchments Using Machine Learning Algorithm-Based Model Parameters Regionalization Methodology
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作者 Houfa Wu Jianyun Zhang +4 位作者 Zhenxin Bao Guoqing Wang Wensheng Wang Yanqing Yang Jie Wang 《Engineering》 SCIE EI CAS CSCD 2023年第9期93-104,共12页
Model parameters estimation is a pivotal issue for runoff modeling in ungauged catchments.The nonlinear relationship between model parameters and catchment descriptors is a major obstacle for parameter regionalization... Model parameters estimation is a pivotal issue for runoff modeling in ungauged catchments.The nonlinear relationship between model parameters and catchment descriptors is a major obstacle for parameter regionalization,which is the most widely used approach.Runoff modeling was studied in 38 catchments located in the Yellow–Huai–Hai River Basin(YHHRB).The values of the Nash–Sutcliffe efficiency coefficient(NSE),coefficient of determination(R2),and percent bias(PBIAS)indicated the acceptable performance of the soil and water assessment tool(SWAT)model in the YHHRB.Nine descriptors belonging to the categories of climate,soil,vegetation,and topography were used to express the catchment characteristics related to the hydrological processes.The quantitative relationships between the parameters of the SWAT model and the catchment descriptors were analyzed by six regression-based models,including linear regression(LR)equations,support vector regression(SVR),random forest(RF),k-nearest neighbor(kNN),decision tree(DT),and radial basis function(RBF).Each of the 38 catchments was assumed to be an ungauged catchment in turn.Then,the parameters in each target catchment were estimated by the constructed regression models based on the remaining 37 donor catchments.Furthermore,the similaritybased regionalization scheme was used for comparison with the regression-based approach.The results indicated that the runoff with the highest accuracy was modeled by the SVR-based scheme in ungauged catchments.Compared with the traditional LR-based approach,the accuracy of the runoff modeling in ungauged catchments was improved by the machine learning algorithms because of the outstanding capability to deal with nonlinear relationships.The performances of different approaches were similar in humid regions,while the advantages of the machine learning techniques were more evident in arid regions.When the study area contained nested catchments,the best result was calculated with the similarity-based parameter regionalization scheme because of the high catchment density and short spatial distance.The new findings could improve flood forecasting and water resources planning in regions that lack observed data. 展开更多
关键词 Parameters estimation Ungauged catchments Regionalization scheme Machine learning algorithms Soil and water assessment tool model
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Research on Risk Assessment Method of Long-Tube Trailer Road Transportation
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作者 Caiyan Dai Wenkun Wang +4 位作者 Ming Xu Chenglong Ma Lianqing Yang Hong Zhao Yuan He 《Journal of Software Engineering and Applications》 2023年第8期420-441,共22页
Road transport safety has always been paid attention to by the safety production managers of enterprises. In this study, cloud model and analytic hierarchy process were applied to the safety of long-tube trailer trans... Road transport safety has always been paid attention to by the safety production managers of enterprises. In this study, cloud model and analytic hierarchy process were applied to the safety of long-tube trailer transport. The opinions of 30 experts were analyzed, from which 29 key parameters were selected. The study addressed the relevance of the parameters and the possibility of automatic collection and transmission to obtain 12 core risk factors. The macro-safety risk indicator system for long-tube trailers was established based on the identified risk indicators. Finally, a risk assessment model for road transport of long tube trailers consisting of 3 dimensions of likelihood, severity and sensitivity was constructed. This model provides a technical method for strengthening the risk control of road transport of long-tube trailers. 展开更多
关键词 Cloud Model Analytic Hierarchy Process Long-Tube Trailer Risk Factors Risk assessment Model
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Effect of Nursing Intervention Based on Caprini Risk Assessment Scale for Venous Thromboembolism in Perioperative Patients with Liver Cancer
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作者 Xiaoxue Song Xiaomei Liu Xi Chen 《Journal of Clinical and Nursing Research》 2023年第3期48-53,共6页
Objective:To explore the effect of nursing intervention based on Caprini risk assessment scale for venous thromboembolism(VTE)in perioperative patients with liver cancer.Methods:A total of 128 hepatocellular cancer(HC... Objective:To explore the effect of nursing intervention based on Caprini risk assessment scale for venous thromboembolism(VTE)in perioperative patients with liver cancer.Methods:A total of 128 hepatocellular cancer(HCC)patients who were hospitalized in our department from January 2021 to March 2022 and met the research criteria were selected.According to odd and even numbers in the order of inclusion,64 cases were divided into two groups:a control group and an observation group.The control group received routine nursing intervention during perioperative period,while the observation group received nursing intervention based on Caprini risk assessment scale for VTE.The incidence of VTE and complications were compared between the two groups.Results:The incidence of VTE and postoperative complications in the observation group were lower than those in the control group(P<0.05).Conclusion:Nursing intervention based on Caprini risk assessment scale for VTE can reduce the incidence of perioperative deep vein thrombosis and complications in patients with liver cancer;thus,it is worthy of clinical application. 展开更多
关键词 Thrombotic risk assessment scale based on Caprini model Deep vein thrombosis Liver cancer Nursing intervention
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GIS Application in Urban Flood Risk Analysis: Midar as a Case Study
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作者 Adil Akallouch Ayoub Al Mashoudi +1 位作者 Mouloud Ziani Rachid Elhani 《Open Journal of Ecology》 2024年第2期148-164,共17页
The significance of this study lies in its exploration of the advanced applications of Geographic Information Systems (GIS) in assessing urban flood risks, with a specific focus on Midar, Morocco. This research is piv... The significance of this study lies in its exploration of the advanced applications of Geographic Information Systems (GIS) in assessing urban flood risks, with a specific focus on Midar, Morocco. This research is pivotal as it showcases that GIS technology is not just a tool for mapping, but a critical component in urban planning and emergency management strategies. By meticulously identifying and mapping flood-prone areas in Midar, the study provides invaluable insights into the potential vulnerabilities of urban landscapes to flooding. Moreover, this research demonstrates the practical utility of GIS in mitigating material losses, a significant concern in flood-prone urban areas. The proactive approach proposed in this study, centered around the use of GIS, aims to safeguard Midar’s population and infrastructure from the devastating impacts of floods. This approach serves as a model for other urban areas facing similar challenges, highlighting the indispensable role of GIS in disaster preparedness and response. Overall, the study underscores the transformative potential of GIS in enhancing urban resilience, making it a crucial tool in the fight against natural disasters like floods. 展开更多
关键词 Geographic Information Systems Risk assessment Models Hydrological modeling Urban Planning Decision-Making Methods Urban Centers
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Study of The Technical Index of Online Learning Behavior Analysis of Nursing Majors on The Superstar Platform Based on The Kirkpatrick Evaluation Model
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作者 Yi Zhang Xiaohua Zhao Jie Li 《Journal of Clinical and Nursing Research》 2024年第4期284-291,共8页
Objective:To analyze the technical indexes of students’online learning behavior analysis based on Kirkman’s evaluation model,sort out the basic indexes of online learning behavior,and extract scientific and efficien... Objective:To analyze the technical indexes of students’online learning behavior analysis based on Kirkman’s evaluation model,sort out the basic indexes of online learning behavior,and extract scientific and efficient evaluation indexes of online learning effect through statistical analysis.Methods:The online learning behavior data of Physiology of nursing students from 2021-2023 and the first semester of 22 nursing classes(3 and 4)were collected and analyzed.The preset learning behavior indexes were analyzed by multi-dimensional analysis and a correlation analysis was conducted between the indexes and the final examination scores to screen for the dominant important indexes for online learning effect evaluation.Results:The study found that the demand for online learning of nursing students from 2021-2023 increased and the effect was statistically significant.Compared with the stage assessment results,the online learning effect was statistically significant.Conclusion:The main indicators for evaluating and classifying online learning behaviors were summarized.These two indicators can help teachers predict which part of students need learning intervention,optimize the teaching process,and help students improve their learning behavior and academic performance. 展开更多
关键词 Kirkpatrick assessment model Superstar platform Online learning behavior Analyzing technical indicators Research
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Human Health Risk Assessment Model of Organic Pollution in Groundwater:Shijiazhuang Industrial Zone 被引量:4
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作者 YANG Mei FEI Yuhong +1 位作者 JU Yiwen LI Huaqi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2011年第6期1508-1517,共10页
In this study, a risk-based management model is developed and applied to an industrial zone. The models proposed by the United States Environmental Protection Agency and Han Bing have been improved by adding a residua... In this study, a risk-based management model is developed and applied to an industrial zone. The models proposed by the United States Environmental Protection Agency and Han Bing have been improved by adding a residual ratio of volatile organic compounds (VOC) after boiling and deleting the related parameters in half-life. Using this improved model, an integrated process was used to assess human health risk level in the study area. Compared with water quality analysis, the results highlight the importance of applying an integrated approach for decision making on risk levels and water protection. The results of this study demonstrated that: (1) Compared with these permissible level standards in China (GB 3838-2002) and National Primary Drinking Water Regulations of the United States, the residents' daily life had not been affected by the groundwater in this area (except for relative bad water quality of HB3-4 and HB3-6); (2) The typical detected organic contaminants of all groundwater samples were chloroform, carbon tetrachloride, trichloroethylene and tetrachloroethene, and the pollution sources were mainly industrial sources by preliminary investigations; (3) As for groundwater, the non-carcinogenic risk values of all samples do not exceed the permissible level of 1.0 and the carcinogenic risk values are relatively lower than the permissible level of 1.00E-06 to 1.00E-04; (4) Drinking water pathway of trichloroethylene and tetrachloroethylene mainly contribute to increasing the health risk of residents' in study areas; (5) In terms of non-carcinogenic risk and carcinogenic risk, the health risk order for drinking water pathway and dermal contact pathway was: drinking water pathway 〉 dermal contact pathway. 展开更多
关键词 groundwater pollution organic contaminants residual rate assessment model human health risk
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Damage assessment for seismic response of recycled concrete filled steel tube columns 被引量:4
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作者 Huang Yijie Xiao Jianzhuang Shen Luming 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2016年第3期607-616,共10页
A model for evaluating structural damage of recycled aggregate concrete filled steel tube (RCFST) columns under seismic effects is proposed in this paper. The proposed model takes the lateral deformation and the eff... A model for evaluating structural damage of recycled aggregate concrete filled steel tube (RCFST) columns under seismic effects is proposed in this paper. The proposed model takes the lateral deformation and the effect of repeated cyclic loading into account. Available test results were collected and utilized to calibrate the parameters of the proposed model. A seismic test for six RCFST columns was also performed to validate the proposed damage assessment model. The main test parameters were the recycled coarse aggregate (RCA) replacement percentage and the bond-slip property. The test results indicated that the seismic performance of the RCFST member depends on the RCA contents and their damage index increases as the RCA replacement percentage increases. It is also indicated that the damage degree of RCFST changes with the variation of the RCA replacement percentage. Finally, comparisons between the RCA contents, lateral deformation ratio and damage degree were implemented. It is suggested that an improvement procedure should be implemented in order to compensate for the performance difference between the RCFST and normal concrete filled steel tubes (CFST). 展开更多
关键词 recycled aggregate concrete (RAC) recycled concrete filled steel tube (RCFST) COLUMN seismicperformance damage assessment model (DAM)
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Relationship between modified homeostasis model assessment/correlative serum factors and diabetic retinopathy among type 2 diabetics with insulin therapy in Guangzhou, China 被引量:6
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作者 Li Hu Dong-Hao Li 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2014年第3期463-468,共6页
AIM:To explore the related risk factors for diabetic retinopathy(DR)in type 2 diabetes with insulin therapy.METHODS:We studied the relationships among blood glucose,serum C-peptide,plasma insulin,beta-cell function an... AIM:To explore the related risk factors for diabetic retinopathy(DR)in type 2 diabetes with insulin therapy.METHODS:We studied the relationships among blood glucose,serum C-peptide,plasma insulin,beta-cell function and the development of DR.Beta-cell function was assessed by a modified homeostasis model assessment(modified HOMA)which was gained by using C-peptide to replace insulin in the homeostasis model assessment(HOMA)of beta-cell function.We also studied the relationships between modified HOMA index and serum C-peptide response to 100 g tasteless steamed bread to determine the accuracy of modified HOMA.RESULTS:Our study group consisted of 170 type 2diabetic inpatients with DR(age:58.35±13.87y,mean±SD)and 205 type 2 diabetic inpatients with no DR(NDR)(age:65.52±11.59y).DR patients had higher age,longer diabetic duration,higher hypertension grade,higher postprandial plasma glucose,higher fluctuation level of plasma glucose,lower body mass index(BMI),lower postprandial serum insulin and C-peptide,lower fluctuation level of serum insulin and C-peptide(P【0.05).In our logistic regression model,duration of diabetes,hypertension grade,fasting plasma insulin and glycosylated hemoglobin(HbA1C)were significantly associated with the presence of DR after adjustment for confounding factors(P【0.05).CONCLUSION:Our results suggested although modified HOMA showed significant correlation to the occurrence of DR on Spearman’s rank-correlationanalysis,logistic regression showed no significant association between these two variables after adjustment for relevant confounding factors(such as age,sex,duration of diabetes,BMI,hypertension grade,HbA1C,plasma insulin).Duration of diabetes,hypertension grade,fasting plasma insulin and HbA1C were independently associated with the development of DR in Chinese type 2 diabetics. 展开更多
关键词 modified homeostasis model assessment diabetic retinopathy INSULIN
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Advances in research on personalized venous thromboembolism risk assessment tools 被引量:3
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作者 Chun-Li Wu Mei Lin +1 位作者 Ying Bao Xiang Wang 《Chinese Nursing Research》 CAS 2016年第3期113-116,共4页
This paper describes the de?nition of venous thromboembolism and introduces to personalized venous thromboembolism risk assessment tools overseas. Thoughts are given on the development, amendment,application and vali... This paper describes the de?nition of venous thromboembolism and introduces to personalized venous thromboembolism risk assessment tools overseas. Thoughts are given on the development, amendment,application and validation of these tools. The paper provides a reference for building personalized venous thromboembolism risk assessment tools in China. 展开更多
关键词 Venous thromboembolism Deep vein thrombosis Pulmonary embolism Risk assessment scale Risk assessment model
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Climatic characteristics of summer high temperature and assessment methods in the large cities of North China 被引量:1
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作者 ZHANG Shangyin ZHANG Dekuan WANG Shourong SONG Yanling 《Journal of Geographical Sciences》 SCIE CSCD 2006年第1期13-22,共10页
Based on the high temperature data of June to August in 1961-2000 in North China, the high temperature weather processes are investigated, and a more complete data set for severe high temperature processes is created.... Based on the high temperature data of June to August in 1961-2000 in North China, the high temperature weather processes are investigated, and a more complete data set for severe high temperature processes is created. The climatic characteristics of adverse high temperature weather in Beijing, Tianjin, Shijiazhuang, Jinan and Taiyuan are analyzed respectively. The major features of the East-Asia Subtropical High and Transformed Continental High are discussed. The outcomes indicate that the influence of both East Asia Subtropical High and Transformed Continental High on these weather events varies, by a larger margin, from one city to another over North China and they are also closely related to the relative humidity. It is found that the behaviours of East-Asia Subtropical High and Transformed Continental High are the major important systems that give rise to the summer high temperature weather over the region. Based on these findings, the 5-day, 10-day and monthly assessment models for such high impact events have been developed. The assessment outcomes prove to be useful in assessing severe high-temperature events in major cities of North China. 展开更多
关键词 North China urban high temperature climatic characteristics assessment model
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New Three-Dimensional Assessment Model and Optimization of Acoustic Positioning System 被引量:1
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作者 Lin Zhao Xiaobo Chen +3 位作者 Jianhua Cheng Lianhua Yu Chengcai Lv Jiuru Wang 《Computers, Materials & Continua》 SCIE EI 2020年第8期1005-1023,共19页
This paper addresses the problem of assessing and optimizing the acoustic positioning system for underwater target localization with range measurement.We present a new three-dimensional assessment model to evaluate th... This paper addresses the problem of assessing and optimizing the acoustic positioning system for underwater target localization with range measurement.We present a new three-dimensional assessment model to evaluate the optimal geometric beacon formation whether meets user requirements.For mathematical tractability,it is assumed that the measurements of the range between the target and beacons are corrupted with white Gaussian noise with variance,which is distance-dependent.Then,the relationship between DOP parameters and positioning accuracy can be derived by adopting dilution of precision(DOP)parameters in the assessment model.In addition,the optimal geometric beacon formation yielding the best performance can be achieved via minimizing the values of geometric dilution of precision(GDOP)in the case where the target position is known and fixed.Next,in order to ensure that the estimated positioning accuracy on the region of interest satisfies the precision required by the user,geometric positioning accuracy(GPA),horizontal positioning accuracy(HPA)and vertical positioning accuracy(VPA)are utilized to assess the optimal geometric beacon formation.Simulation examples are designed to illustrate the exactness of the conclusion.Unlike other work that only uses GDOP to optimize the formation and cannot assess the performance of the specified size,this new three-dimensional assessment model can evaluate the optimal geometric beacon formation for each dimension of any point in three-dimensional space,which can provide guidance to optimize the performance of each specified dimension. 展开更多
关键词 Acoustic positioning system three-dimensional assessment model positioning accuracy DOP optimal configuration
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Smoke Hazard Assessment Model Based on Fire Dynamics Simulator and FED Model 被引量:2
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作者 Nianfeng Li Shang Zhou +1 位作者 Zhiguo Xiao Yifei Zhao 《Journal of Computer and Communications》 2020年第9期81-93,共13页
Smoke is the main cause of fire death. In order to minimize the potential danger of smoke hazard, a rational VR based fire training simulator should fully consider all aspects of smoke hazard. In the simulator, the vi... Smoke is the main cause of fire death. In order to minimize the potential danger of smoke hazard, a rational VR based fire training simulator should fully consider all aspects of smoke hazard. In the simulator, the visualization of data based on FDS (Fire Dynamics Simulator) and FED fire dynamic data and volume rendering is further optimized, which can be effectively and quickly applied to virtual fire protection. In addition, a comprehensive smoke hazard assessment model based on FED and FED is established to assess the IHD value of different paths, which represents the safety of different paths, and can be used for evacuation or rescue in virtual training. Taking the case of campus fire drill as an experiment, the research shows the accuracy and effectiveness of smoke assessment based on FDS and FED model. The road force with the highest safety can be selected through the comprehensive model. So the assessment model is proved to be valuable. 展开更多
关键词 Smoke Hazard Smoke Visualization Integrated Smoke assessment Model FDS FED
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