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A Quality Evaluation System for Dissertation Based on Fuzzy Analytic Hierarchy Process
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作者 Kang Xu Zhenhao Zhang +4 位作者 Shuo Wang Yunhui Lv Jiafei Li Xiaodan Cai Yongchun Cui 《Applied Mathematics》 2024年第7期441-454,共14页
A dissertation is a research report or scientific paper written by an author to obtain a certain degree. It reflects postgraduates’ research achievements and the educational quality of an institute, even a country. T... A dissertation is a research report or scientific paper written by an author to obtain a certain degree. It reflects postgraduates’ research achievements and the educational quality of an institute, even a country. To construct an optimized quality evaluation system for postgraduate dissertation (QESPD), we summarized the influencing factors and invited 10 experienced specialists to rate and prioritize them based on fuzzy analytic hierarchy process. Four primary indicators (innovation, integrity, scientificity and normativity) and 16 sub-indicators were selected to form the evaluation system. The order of primary indicators by weight, was innovation (0.4269), scientificity (0.2807), integrity (0.1728) and normativity (0.1196). The top five sub-dimensions were theoretical originality, scientific value, data reliability, design rationality and evidence credibility. To demonstrate the effectiveness of the proposed system, a case study was performed. In the case study, it was demonstrated that the established two-index-hierarchy QESPD in this study was a more scientific and reasonable evaluation system worthy of promotion and application. 展开更多
关键词 DISSERTATION quality evaluation Indicator System Fuzzy Analytic Hierarchy Process Case Study
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Research on the prognostic value of adjusting intraperitoneal threedimensional quality evaluation mode in laparoscopic cholecystectomy patients
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作者 Yuan Zhou Zhan-Qing Chen 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第4期1078-1086,共9页
BACKGROUND Benign gallbladder diseases have become a high-prevalence condition not only in China but also worldwide.The main types of benign gallbladder diseases include gallbladder polyps,acute and chronic cholecysti... BACKGROUND Benign gallbladder diseases have become a high-prevalence condition not only in China but also worldwide.The main types of benign gallbladder diseases include gallbladder polyps,acute and chronic cholecystitis,and gallstones,with gallstones being the most common,accounting for over 70%of cases.Although the mortality rate of benign gallbladder diseases is low,they carry obvious potential risks.Studies have shown that an increased incidence of benign gallbladder diseases can increase the risk of cardiovascular diseases and gallbladder cancer,resulting in a substantial disease burden on patients and their families.AIM To assess the medical utility of the Configuration-Procedure-Consequence(CPC)three-dimensional quality evaluation model in modulating the prognosis of laparoscopic cholecystectomy patients.METHODS A total of 98 patients who underwent laparoscopic cholecystectomy in our hospital from February 2020 to January 2022 were selected as the subjects.According to the random number table method,they were divided into a study group and a control group,with 49 patients in each group.The control group received routine perioperative care,while the study group had the addition of the CPC three-dimensional quality evaluation.The postoperative recovery-related indicators(time to first flatus,time to oral intake,time to ambulation,hospital stay),stress indicators(cortisol and adrenaline levels),distinctions in anxiety and RESULTS The time to first flatus,time to oral intake,time to ambulation,and hospital stay of the study group patients were obviously lower than those of the control group patients,with statistical significance(P<0.05).On the 1st day after admission,there were no obvious distinctions in cortisol and adrenaline levels in blood samples,as well as in the Self-Rating Anxiety Scale(SAS)and Self-Rating Depression Scale(SDS)scores between the study group and the control group(P>0.05).However,on the 3rd day after surgery,the cortisol and adrenaline levels,as well as SAS and SDS scores of the study group patients,were obviously lower than those of the control group patients(P<0.05).The study group had 2 cases of incisional infection and 1 case of pulmonary infection,with a total incidence of complications of 6.12%(3/49),which was obviously lower than the 20.41%(10/49)in the control group(P<0.05).CONCLUSION Implementing the CPC three-dimensional quality evaluation model for patients undergoing laparoscopic cholecystectomy can help accelerate their perioperative recovery process,alleviate perioperative stress symptoms,mitigate anxiety,depression,and other adverse emotions,and to some extent,reduce the incidence of perioperative complications. 展开更多
关键词 Configuration-Procedure-Consequence Three-dimensional quality evaluation Laparoscopic Cholecystectomy Recovery process Anxiety and depression COMPLICATIONS
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Grey Clustering Evaluation on Regional Eco-environmental Quality Based on Normalized Index Value 被引量:7
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作者 TIAN Wen-xin, LI Zuo-yong, LIU Wei, YU Chun-xue College of Resources and Environmental Sciences, Chengdu University of Information Technology, Chengdu 610225, China 《Meteorological and Environmental Research》 CAS 2011年第4期65-67,71,共4页
[Objective] The aim was to assess regional eco-environmental quality by means of grey clustering method based on normalized index value. [Method] Eco-environmental quality in Chaohu basin was assessed by using grey cl... [Objective] The aim was to assess regional eco-environmental quality by means of grey clustering method based on normalized index value. [Method] Eco-environmental quality in Chaohu basin was assessed by using grey clustering method based on normalized index value, and the evaluation results were compared with those of unascertained measure method to verify the feasibility of grey clustering method used to evaluate regional eco-environmental quality. [Result] In the grey clustering assessment method based on normalized index value, indices whose standard normalized values in the same grade were close to each other were classified into one class and had the same whitening function, which reduced the number of whitening functions. Grey clustering method based on normalized index value was used to assess eco-environmental quality in Chaohu basin, and the evaluation results were basically in accordance with those of unascertained measure method, namely eco-environmental quality in Hefei, Chaohu and Lu’an belonged to the third (pass), fourth (worse) and fifth grade (bad), except for one grade difference in overall basin, and the results showed that the method had practicality and could be applied to assess regional eco-environmental quality. [Conclusion] The study could provide theoretical foundation for the establishment of comprehensive management countermeasures of regional ecological environment. 展开更多
关键词 NORMALIZATION Gray clustering method eco-environment quality evaluation Chaohu basin China
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Eco-environmental Quality Evaluation of Coal City Based on AHP-PCA Model 被引量:17
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作者 李峰 刘小阳 +1 位作者 于雪涛 刘文龙 《矿业安全与环保》 北大核心 2017年第5期103-106,110,共5页
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Integrated Evaluation Model for Eco-Environmental Quality in Mountainous Region Based on Remote Sensing and GIS 被引量:1
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作者 LI Ainong WANG Angsheng +2 位作者 HE Xiaorong FENG Wenlan ZHOU Wancun 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第4期969-976,共8页
Based on Remote Sensing (RS), Geographic Information System (GIS), and combining Principal Component Analysis, this paper designed a numerical integrated evaluation model for mountain eco-environment on the base ... Based on Remote Sensing (RS), Geographic Information System (GIS), and combining Principal Component Analysis, this paper designed a numerical integrated evaluation model for mountain eco-environment on the base of grid scale. Using this model, we evaluated the mountain eco-environmental quality in a case study area-the upper reaches of Minjiang River, and achieved a good result, which accorded well with the real condition. The study indicates that, the integrated evaluation model is suitable for multi-layer spatial factor computation, effectively lowing man's subjective influence in the evaluation process; treating the whole river basin as a system, the model shows full respect to the circulation of material and energy, synthetically embodies the determining impact of such natural condition as water-heat and landform, as well as human interference in natural eco-system; the evaluation result not only clearly presents mountainous vertical distribution features of input factors, but also provides a scientific and reliable thought for quantitatively evaluating mountain eco-environment. 展开更多
关键词 eco-environment evaluation model spatial principal component analysis RS (remote sensing) GIS (geographic information system)
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Universal Index Formula of Parameterized Combination Operator for Eco-environmental Quality Evaluation
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作者 YU Chun-xue LI Zuo-yong TIAN Wen-xin 《Meteorological and Environmental Research》 CAS 2011年第8期74-77,共4页
[Objective] The aim was to evaluate the regional eco-environmental quality by using the universal index formula of parameterization combination operator based normalized index values.[Method] Through setting reference... [Objective] The aim was to evaluate the regional eco-environmental quality by using the universal index formula of parameterization combination operator based normalized index values.[Method] Through setting reference values and normalized transformation formulae for typical ecological environmental indexes appropriately,the difference among the standard normalized values would become very small after normalized transformation,and the ecological environmental indices expressed by normalized values can be equivalent to normalized indices.Under certain optimization conditions,shuffled frog leaping based on immune evolutionary particle swarm optimization algorithm was applied to optimize the parameters in parameterization combination operator formula,and the universal index formula suited to eco-environmental quality assessment was established finally.[Result] The universal index formula of parameterization combination operator,appropriate for any m(1≤m≤23) ecological environmental indices,was used to assess the eco-environmental quality of towns surrounding Headland Reservoir,and the results were in full accordance with those of unascertained measure method,that is,the eco-environmental quality of five towns around Headland Reservoir was the fourth grade.[Conclusion]The universal index formula of parameterization combination operator,suited to eco-environmental quality evaluation,is simple and intuitive in form,easy in computation and universal in application. 展开更多
关键词 NORMALIZATION eco-environmental quality evaluation Parameterization combination operator Universal index formula China
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Evaluation and Driving Force Analysis of Cultivated Land Quality in Black Soil Region of Northeast China 被引量:1
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作者 WANG Mingchang LIU Xingnan +4 位作者 LIU Ziwei WANG Fengyan LI Xiaoyan HOU Guanglei ZHAO Shijun 《Chinese Geographical Science》 SCIE CSCD 2023年第4期601-615,共15页
Cultivated land is an important natural resource to ensure food,ecological and economic security.The cultivated land quality evaluation(CQE)is greatly significant for protecting and managing cultivated land.In this st... Cultivated land is an important natural resource to ensure food,ecological and economic security.The cultivated land quality evaluation(CQE)is greatly significant for protecting and managing cultivated land.In this study,320 counties in the black soil region of Northeast China(BSRNC)represent the research units used to construct the CQE system measuring the soil properties(SP),cultivated land productivity(CLP),ecological environment(EE)and social economy(SE).The total of 19 factors were selected to calculate the integrated fertility index(IFI)and divided into grades.Simultaneously,we used the coupling coordination degree model to comprehensively analyze the spatial pattern of the cultivated land quality(CLQ)in the BSRNC,and use the structural equation model(SEM)to analyze the driving mechanism.The results show the following:1)The CLQ of 262 counties in the BSRNC is in a state of coupling and coordination,and the coupling and coordination degree presents a spatial distribution pattern of‘high in the southwest and northeast,low in the northwest and southeast’.The coordinated development degree of 271 counties is between 0.4 and 0.6,which is in a transitional state between coordination and disorder.2)The CLQ in the BSRNC is generally good,with an average grade of 3.High-quality cultivated land accounts for 58.45%of all counties,middle-and upper-quality cultivated land accounts for 27.05%,and poor-quality cultivated land accounts for 14.49%.3)The SEM analysis shows that the SP,CLP,EE,and SE all influence the CLQ.Among them,the SP has the largest driving force on the CLQ,while the SE has the smallest driving force on it.The results confirm that the main factors affecting the evaluation results are crop productivity level,normalized difference vegetation index,ratio vegetation index,difference vegetation index,and organic carbon content.When implementing protection measures in counties with a low CLQ,considering a balanced coordination of multiple systems and reasonably controlling the quality degradation are important.This study provides the current situation and driving factors of the CLQ in the BSRNC and will play an important role in black soil governance and utilization. 展开更多
关键词 cultivated land quality evaluation(CQE) black soil region of Northeast China(BSRNC) coupling coordination degree model structural equation model(SEM) driving forces
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Quality evaluation of land reclamation in mining area based on remote sensing
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作者 Shidong Wang Jjianhua Guo +2 位作者 Yang Yu Pujie Shi Hebing Zhang 《International Journal of Coal Science & Technology》 EI CAS CSCD 2023年第3期204-213,共10页
Several deficiencies exist in the present evaluation of land reclamation quality in mining areas.These include the absence of an established set of evaluation index systems and standard acceptance criteria,as well as ... Several deficiencies exist in the present evaluation of land reclamation quality in mining areas.These include the absence of an established set of evaluation index systems and standard acceptance criteria,as well as the use of traditional sam-pling techniques,which are costly and in eficiency,and time-consuming.Compared with the traditional sampling survey methods,remote sensing has the advantages of a wide detection range,diverse information collection,multiple data-acquiring strategies,high speed,and short cycle.In this study,we used the Xinzhuang coal mining field in Yongcheng,Henan Province as an example to extract information and invert surface parameters using remote sensing techniques,based on national and local reclamation regulations and standards.Subsequently,using remote sensing,we constructed an index system for evaluating land reclamation quality in three aspects:reclaiming project quality,soil quality,and ecological benefits.Through the grading standards of evaluation indicators and quantitative remote sensing models,we determined the extracted information on the area of indicators,roads,ditches,soil moisture,organic matter,and ecological benefits after reclamation.Based on this,we established a quality evaluation model for mining land reclamation using an improved index and method.The evaluation units were divided,and the weight of the evaluation index was determined using the analytic hierarchy process and data envelopment analysis(AHP-DEA)method.The land reclamation quality in the study area was comprehensively evaluated,field accuracy was verified,and the results were analyzed.The results show that,except for the removal of roads,houses,and fishponds in the study area,all 13 evaluation units achieved a score of 60 points or higher.The quality of reclamation met the standards,and the evaluation results were consistent with the conclusions of the field investigation and project acceptance report,demonstrating the reliability and feasibility of the method developed in this study.The research results will provide technical support for the scientific evaluation of land reclamation quality. 展开更多
关键词 Remote sensing Mining area land-Reclamation quality evaluation SOIL
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Multidimensional Quality Evaluation of Graduate Thesis:Based on the Probabilistic Linguistic MABAC Method
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作者 Yuyan Luo Xiaoxu Zhang +2 位作者 Tao Tong Yong Qin Zheng Yang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第11期2049-2076,共28页
Graduate education is the main way to train high-level innovative talents,the basic layout to cope with the global talent competition,and the important cornerstone for implementing the innovation-driven development st... Graduate education is the main way to train high-level innovative talents,the basic layout to cope with the global talent competition,and the important cornerstone for implementing the innovation-driven development strategy and building an innovation-driven country.Therefore,graduate education is of great remarkably to the development of national education.As an important manifestation of graduate education,the quality of a graduate thesis should receive more attention.It is conducive to promoting the quality of graduates by supervising and examining the quality of the graduate thesis.For this purpose,this work is based on textmining,expert interviews,and questionnaire surveys to obtain the factors influencing the quality of a graduate thesis first.Then,through three rounds of expert consultation,a multidimensional evaluation indicator system for the graduate thesis quality is built.Furthermore,probabilistic linguistic termsets(PLTSs)are utilized to obtain the initial evaluation information and apply the stepwise weight assessment ratio analysis method to determine the weights of attributes.In the ensuing step,the novel multi-attribute border approximation area comparison based on the PLTS method is established.Finally,the proposed method is employed in a case study concerning the quality evaluation of a graduate thesis and the effectiveness of this approach is further illustrated. 展开更多
关键词 Probabilistic linguistic term sets PL-MABAC SWARA quality evaluation graduate thesis
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Employment Quality EvaluationModel Based on Hybrid Intelligent Algorithm
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作者 Xianhui Gu Xiaokan Wang Shuang Liang 《Computers, Materials & Continua》 SCIE EI 2023年第1期131-139,共9页
In order to solve the defect of large error in current employment quality evaluation,an employment quality evaluation model based on grey correlation degree method and fuzzy C-means(FCM)is proposed.Firstly,it analyzes... In order to solve the defect of large error in current employment quality evaluation,an employment quality evaluation model based on grey correlation degree method and fuzzy C-means(FCM)is proposed.Firstly,it analyzes the related research work of employment quality evaluation,establishes the employment quality evaluation index system,collects the index data,and normalizes the index data;Then,the weight value of employment quality evaluation index is determined by Grey relational analysis method,and some unimportant indexes are removed;Finally,the employment quality evaluation model is established by using fuzzy cluster analysis algorithm,and compared with other employment quality evaluation models.The test results show that the employment quality evaluation accuracy of the design model exceeds 93%,the employment quality evaluation error can meet the requirements of practical application,and the employment quality evaluation effect is much better than the comparison model.The comparison test verifies the superiority of the model. 展开更多
关键词 Employment quality fuzzy c-means clustering algorithm grey correlation analysis method evaluation model index system comparative test
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Application of Eye Movement Analysis in Landscape Visual Quality Evaluation
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作者 Dewang LIU Xiaoyu HU +1 位作者 Xinhui HE Baoyong LI 《Meteorological and Environmental Research》 CAS 2023年第3期17-24,共8页
The existing methods of landscape visual quality evaluation is mostly based on people's subjective feelings,and the objectivity and scientificity of evaluation results are insufficient.As an important means of exp... The existing methods of landscape visual quality evaluation is mostly based on people's subjective feelings,and the objectivity and scientificity of evaluation results are insufficient.As an important means of experimental psychology,eye movement technology can show great advantages and potential in landscape visual quality evaluation.On the basis of combing and summarizing the relevant literature,based on the explanation of the technical principle of eye movement analysis,the application field,research content,technical methods and other aspects of eye movement analysis were reviewed.The application prospect of eye movement technology in landscape visual quality evaluation was explored to provide theoretical reference for the in-depth evaluation and research of landscape visual quality evaluation theory. 展开更多
关键词 Eye movement analysis Eye movement tracking Landscape visual quality Visual perception evaluation
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Quantitative evaluation and spatial differentiation of eco-environmental livability in Zhejiang Province, China 被引量:3
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作者 WANG Yi ZHU Ying-ming +1 位作者 YU Mao-jun XU Jing 《Journal of Mountain Science》 SCIE CSCD 2020年第6期1491-1508,共18页
The scientific analyses of the spatial patterns of regional eco-environment livability,along with the explorations of the correlations between ecoenvironments and population and economic activity distributions,are of ... The scientific analyses of the spatial patterns of regional eco-environment livability,along with the explorations of the correlations between ecoenvironments and population and economic activity distributions,are of major significance in the guidance of the coordinated development between social economies,natural resources,and environments.In this study,the topography,climate,hydrology,land cover,air quality,and the dangers presented by natural hazards in the study area were investigated in order to establish an evaluation model for the regional eco-environmental livability.Then,the observed spatial patterns and regional differences in the eco-environmental livability,as well as their relationships with the distributions of population and economic activities in Zhejiang Province,were investigated.The results showed that the ecoenvironmental livability in Zhejiang Province displayed a gradual decreasing trend from southwest to northeast,as well as from the mountains to the hills,valleys,and plains areas.During the compartmentalization of the eco-environmental livability,it was observed that the lowest livable area covered the largest population,accounting for approximately 29.64%of the total population in the study area.The higher livable areas covered the widest land areas,accounting for approximately 26.15%of the total area.Moreover,it was found that the eco-environmental livability in the mountain areas was higher than that in the plain areas in Zhejiang Province.Furthermore,the ecoenvironmental livability was found to have a significant exponential relationship with the population and GDP densities of Zhejiang Province,with the R^2 of the curve-fittings reaching 0.835 and 0.656,respectively.However,it was determined that the coefficient of the exponential function was negative,which indicated that a strong negative relationship existed between the eco-environmental livability and densities of the population and economic activities.It was assumed that the impacts of anthropogenic factors were the fundamental causes of this negative correlation.This study introduced two new factors(air quality and natural hazards)into the evaluation framework of eco-environmental livability.As a result,a more comprehensive model was established for the evaluation of eco-environmenta livability in certain segments of the study area Additionally,the correlation between ecoenvironment livability and human activities was discussed in-depth,which can potentially provide theoretical and practical guidance for the implementation of eco-livability in China,and possibly even those of other vast developing countries. 展开更多
关键词 eco-environment LIVABILITY Quantitative evaluations Spatial differentiation Zhejiang Province
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The Evaluation of Eco-environmental Sensitivity in Ordos City 被引量:2
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作者 Yanhong XU Xijun YAO +1 位作者 Libo LU Haijiao FAN 《Asian Agricultural Research》 2015年第2期66-73,共8页
This paper aims to reveal the difference of eco-environmental sensitivity and its influencing factors in the study area through carrying out the eco-environmental sensitivity evaluation based on land ecological securi... This paper aims to reveal the difference of eco-environmental sensitivity and its influencing factors in the study area through carrying out the eco-environmental sensitivity evaluation based on land ecological security for 8 counties of Ordos City. Using fragstats landscape pattern analysis,GIS space method and RS analysis,based on ground investigation,this paper uses information mining and data analysis to extract index data for every village in the study area,carry out comprehensive quantitative evaluation,and finally calculate the comprehensive scores of eco-environmental sensitivity of the areas. The paper concludes that the highly sensitive areas and extremely sensitive areas are mainly concentrated in the eastern region of the eastern hilly and gully region and southern region of the Mu Us Desert in Ordos. The main reasons include severe soil erosion in hilly and gully region and serious desertification in southern Mu Us Desert area. So it is necessary to strengthen ecological environment protection in local areas. 展开更多
关键词 ORDOS CITY eco-environment Sensitivity evaluation
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Evaluation Study on the Level of High-Quality Development of the Construction Industry in Henan Province of China
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作者 Ximei Kong Zhiyuan Feng 《Open Journal of Applied Sciences》 CAS 2023年第3期366-382,共17页
Based on the data of the construction industry in Henan Province, China, from 2005 to 2020, the high-quality development level of the construction industry in Henan Province is measured. Firstly, this paper constructs... Based on the data of the construction industry in Henan Province, China, from 2005 to 2020, the high-quality development level of the construction industry in Henan Province is measured. Firstly, this paper constructs the indicator system based on the high-quality development theory and the characteristic of the construction industry from seven dimensions: industrial scale, industrial efficiency, industrial benefits, industrial innovation, industrial risk, industrial potential, and the green development of the construction industry. Secondly, using the global principal component analysis (PCA) method to measure the high-quality development level. Thirdly, cluster analysis is applied to measure the relative changes of various dimensions in different stages. The results show that overall the high-quality development level of the construction industry in Henan province is increasing, but different indicators perform differently in various stages, and the changes in real estate policies have a significant impact on this. Finally, based on these findings, we think it is better to reduce real estate dependence, promote the application of new materials and technologies and maintain the stability of real estate policies. 展开更多
关键词 Construction Industry High-quality Development evaluation
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Entropy method for determination of weight of evaluating indicators in fuzzy synthetic evaluation for water quality assessment 被引量:211
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作者 ZOU Zhi-hong YUN Yi SUN Jing-nan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第5期1020-1023,共4页
Considering the difficulty of fuzzy synthetic evaluation method in calculation of the multiple factors and ignorance of the relationship among evaluating objects, a new weight evaluation process using entropy method w... Considering the difficulty of fuzzy synthetic evaluation method in calculation of the multiple factors and ignorance of the relationship among evaluating objects, a new weight evaluation process using entropy method was introduced. This improved method for determination of weight of the evaluating indicators was applied in water quality assessment of the Three Gorges reservoir area. The results showed that this method was favorable for fuzzy synthetic evaluation when there were more than one evaluating objects. One calculation was enough for calculating every monitoring point. Compared with the original evaluation method, the method predigested the fuzzy synthetic evaluation process greatly and the evaluation results are more reasonable. 展开更多
关键词 water quality evaluation FUZZY weight of evaluating indicator entropy method
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Growth behavior and resource potential evaluation of gas hydrate in core fractures in Qilian Mountain permafrost area, Qinghai-Tibet Plateau 被引量:1
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作者 Qing-guo Meng Chang-ling Liu +5 位作者 Zhen-quan Lu Xi-luo Hao Cheng-feng Li Qing-tao Bu Yun-kai Ji Jia-xian Wang 《China Geology》 CAS CSCD 2023年第2期208-215,共8页
The Qilian Mountain permafrost area located in the northern of Qinghai-Tibet Plateau is a favorable place for natural gas hydrate formation and enrichment,due to its well-developed fractures and abundant gas sources.U... The Qilian Mountain permafrost area located in the northern of Qinghai-Tibet Plateau is a favorable place for natural gas hydrate formation and enrichment,due to its well-developed fractures and abundant gas sources.Understanding the formation and distribution of multi-component gas hydrates in fractures is crucial in accurately evaluating the hydrate reservoir resources in this area.The hydrate formation experiments were carried out using the core samples drilled from hydrate-bearing sediments in Qilian Mountain permafrost area and the multi-component gas with similar composition to natural gas hydrates in Qilian Mountain permafrost area.The formation and distribution characteristics of multi-component gas hydrates in core samples were observed in situ by X-ray Computed Tomography(X-CT)under high pressure and low temperature conditions.Results show that hydrates are mainly formed and distributed in the fractures with good connectivity.The ratios of volume of hydrates formed in fractures to the volume of fractures are about 96.8%and 60.67%in two different core samples.This indicates that the fracture surface may act as a favorable reaction site for hydrate formation in core samples.Based on the field geological data and the experimental results,it is preliminarily estimated that the inventory of methane stored in the fractured gas hydrate in Qilian Mountain permafrost area is about 8.67×1013 m3,with a resource abundance of 8.67×108 m3/km2.This study demonstrates the great resource potential of fractured gas hydrate and also provides a new way to further understand the prospect of natural gas hydrate and other oil and gas resources in Qilian Mountain permafrost area. 展开更多
关键词 Gas hydrate Growth behavior Core fracture Rock quality Designation Resource potential evaluation Engineering Oil and gas exploration Qilian Mountain permafrost area Qinghai-Tibet Plateau
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Evaluation, prediction, and protection of water quality in Danjiangkou Reservoir, China 被引量:14
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作者 Xiao-kang Xin Ke-feng Li +1 位作者 Brian Finlayson Wei Yin 《Water Science and Engineering》 EI CAS CSCD 2015年第1期30-39,共10页
The water quality in the Danjiangkou Reservoir has attracted considerable attention from the Chinese public and government since the announcement of the Middle Route of the South to North Water Diversion Project (SN... The water quality in the Danjiangkou Reservoir has attracted considerable attention from the Chinese public and government since the announcement of the Middle Route of the South to North Water Diversion Project (SNWDP), which commenced transferring water in 2014. Integrated research on the evaluation, prediction, and protection of water quality in the Danjiangkou Reservoir was carried out in this study in order to improve environmental management. Based on 120 water samples, wherein 17 water quality indices were measured at 20 monitoring sites, a single factor evaluation method was used to evaluate the current status of water quality. The results show that the main indices influencing the water quality in the Danjiangkou Reservoir are total phosphorus (TP), permanganate index (CODM,), dissolved oxygen (DO), and five-day biochemical oxygen demand (BODs), and the concentrations of TP, BODs, ammonia nitrogen (NH3--N), CODM,, DO, and anionic surfactant (Surfa) do not reach the specified standard levels in the tributaries. Seasonal Mann--Kendall tests indicated that the CODMn concentration shows a highly significant increasing trend, and the TP concentration shows a significant increasing trend in the Danjiangkou Reservoir. The distribution of the main water quality indices in the Danjiangkou Reservoir was predicted using a two-dimensional water quality numerical model, and showed that the sphere of influence from the tributaries can spread across half of the Han Reservoir if the pollutants are not controlled. Cluster analysis (CA) results suggest that the Shending River is heavily polluted, that the Jianghe, Sihe, and Jianhe rivers are moderately polluted, and that they should be the focus of environmental remediation. 展开更多
关键词 Water quality Single factor evaluation method Mann--Kendall test Numerical modeling Cluster analysis Dangjiangkou Reservoir
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High-resolution modeling and evaluation of ozone air quality of Osaka using MM5-CMAQ system 被引量:7
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作者 SHRESTHA Kundan Lal KONDO Akira +1 位作者 KAGA Akikazu INOUE Yoshio 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第6期782-789,共8页
High-resolution modeling approach is increasingly being considered as a necessary step for improving the monitoring and predictions of regional air quality. This is especially true for highly urbanized region with com... High-resolution modeling approach is increasingly being considered as a necessary step for improving the monitoring and predictions of regional air quality. This is especially true for highly urbanized region with complex terrain and land-use. This study uses Community Multiscale Air Quality (CMAQ) model coupled with MM5 mesoscale model for a comprehensive analysis to assess the suitability of such high-resolution modeling system in predicting ozone air quality in the complex terrains of Osaka, Japan. The 1-km and 3-kin grid domains were nested inside a 9-km domain and the domain with 1-km grid covered the Osaka region. High-resolution Grid Point Value-Mesoscale Model (GPV-MSM) data were used after suitable validation. The simulated ozone concentrations were validated and evaluated using statistical metrics using performance criteria set for ozone. Daily maxima of ozone were found better simulated by the 1-krn grid domain than the coarser 9-km and 3-km domains, with the maximum improvement in the mean absolute gross error about 3 ppbv. In addition, 1-km grid results fared better than other grids at most of the observation stations that showed noticeable differences in gross error as well as correlation. These results amply justify the use of the integrated high-resolution MM5-CMAQ modeling system in the highly urbanized region, such as the Osaka region, which has complex terrain and land-use. 展开更多
关键词 air quality model evaluation OZONE Community Multiscale Air quality MM5 statistical analysis
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Objective Evaluation Method of Steering Comfort Based on Movement Quality Evaluation of Driver Steering Maneuver 被引量:4
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作者 YANG Yiyong LIU Yahui +2 位作者 WANG Man JI Run JI Xuewu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第5期1027-1037,共11页
The existing research of steering comfort mainly focuses on the subjective evaluation,aiming at designing and optimizing the steering system.In the development of steering system,especially the evaluation of steering ... The existing research of steering comfort mainly focuses on the subjective evaluation,aiming at designing and optimizing the steering system.In the development of steering system,especially the evaluation of steering comfort,the objective evaluation methods considered the kinematic characteristics of driver steering maneuver are not proposed,which means that the objective evaluation of steering cannot be conducted with the evaluation of kinematic characteristics of driver in steering maneuver.In order to propose the objective evaluation methods of steering comfort,the evaluation of steering movement quality of driver is developed on the basis of the study of the kinematic characteristics of steering maneuver.First,the steering motion trajectories of the driver in both comfortable and certain extreme uncomfortable operation conditions are detected using the Vicon motion capture system.The operation conditions are under the restrictions of the vertical height and horizontal distance between steering wheel center and the H-point of driver,and the steering resisting torque else.Next,the movement quality evaluation of driver steering maneuver is assessed using twelve kinds of evaluation indices based on the kinematic analyses of the steering motion trajectories to propose an objective evaluation method.Finally,an integrated discomfort index of steering maneuver is proposed on the basis of the regression analysis of subjective evaluation rating and the movement quality evaluation indices,including the Jerk,Discomfort and Joint Torque indices.The test results show that the proposed integrated discomfort index gives a good fitting with the subjective evaluation of discomfort,which means it can be used to evaluate or predict the discomfort level of steering maneuver.This paper proposes an objective evaluation method of steering comfort based on the movement quality evaluation of driver steering maneuver. 展开更多
关键词 steering maneuver movement quality evaluation DRIVER DISCOMFORT
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An Evaluation Scale of Medical Services Quality Based on “Patients' Experience” 被引量:5
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作者 田常俊 田悦 张亮 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2014年第2期289-297,共9页
An evaluation scale of medical services quality was developed on the basis of "patients' experience". The questionnaires were developed by, among others, searching relevant literature, col- lecting well-established... An evaluation scale of medical services quality was developed on the basis of "patients' experience". The questionnaires were developed by, among others, searching relevant literature, col- lecting well-established assessment scales, measuring patients' experience and satisfaction, brain-storming, literature analysis. Delphi method was adopted for expert consultation. Scale items were screened and revised. The key indexes were converted. Field surveys were conducted for testing the reliability and validity of the scale. Our modified evaluation scale for measuring medical services quality based on "patients' experience" included 6 dimensions (tangibility, reliability, responsiveness, assurance, empathy and continuity), and 50 items. The novel scale based on "patients' experience" may better serve the purpose of assessin~ medical services quality. 展开更多
关键词 patients' experience medical services quality evaluation SCALE
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