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Numerical test and evaluating method of impact trend of rock-coal system
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作者 蒋金泉 程家国 +1 位作者 曲华 董建军 《Journal of Coal Science & Engineering(China)》 2008年第1期12-18,共7页
The impact trend of reck-coal system was studied by the method of accumulating and releasing of deformation energy and interaction of rock-coal system. The system model of roof-coal-floor was established. Based on the... The impact trend of reck-coal system was studied by the method of accumulating and releasing of deformation energy and interaction of rock-coal system. The system model of roof-coal-floor was established. Based on the RFPA software, rock fracture process analysis system, the numerical test of deformation, fracture and energy transmission of nonlinear and nonhomogeneous rock-coal system, and the numerical test and evaluating method of impact trend of reck-coal system were achieved. When the same coal seam was in different roof and floor conditions, the fracture process of reck-coal system can be classified as gradual, sudden and delayed fracture three kinds, and their impact trend can be classified as void, intense and medium correspondingly. The rock-coal system's impact trend is evaluated by the system impact index p and burst expanding forms. The criteria μ are μ〈1.0, 1.0≤μ〈l .5 and μ≥1.5 when the impact trend is void, intense or medium, which are tested and verified by the No.2 and No.4 coal seams in Sun- cun mine. 展开更多
关键词 impact trend rock-coal system numerical test impact energy index evaluating method
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Microcystis aeruginosa removal over MOFs-based materials and the evaluation methods:State-of-the-art review
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作者 Hong-Yu Chu Guang-Chi Liu +2 位作者 Fu-Xue Wang Lian-Sheng Cui Chong-Chen Wang 《Chinese Chemical Letters》 2025年第10期200-211,共12页
The harmful algal bloom primarily caused by Microcystis aeruginosa(M.aeruginosa)has become one of the serious biological pollution issues in actual water,which has received intense attention worldwide.Over the past ye... The harmful algal bloom primarily caused by Microcystis aeruginosa(M.aeruginosa)has become one of the serious biological pollution issues in actual water,which has received intense attention worldwide.Over the past years,increasing number of publications have reported that metal-organic frameworks(MOFs)based functional materials exhibited significant inhibition against M.aeruginosa via multiple mechanisms,but no review papers systematically presented progresses regarding MOFs-based materials for M.aeruginosa control up to now.With this review paper,we summarized the state-of-the-art studies of MOFsbased materials for M.aeruginosa removal,comparing and discussing the design strategies of MOFs-based materials and their antimicrobial mechanisms.Meanwhile,we discussed methods for evaluating the water purification performances of MOFs-based materials against M.aeruginosa.Finally,the perspectives for design of novel MOFs-based functional materials and application scenarios were proposed to provide an outlook on areas where greater efforts should be made in the future. 展开更多
关键词 Metal-organic framework Microcystis aeruginosa Inhibition mechanism Evaluation method PERSPECTIVE
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Data credibility evaluation method for formation water in oil and gas fields and its influencing factors
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作者 LI Wei XIE Wuren +2 位作者 WU Saijun SHUAI Yanhua MA Xingzhi 《Petroleum Exploration and Development》 2025年第2期361-376,共16页
The formation water sample in oil and gas fields may be polluted in processes of testing, trial production, collection, storage, transportation and analysis, making the properties of formation water not be reflected t... The formation water sample in oil and gas fields may be polluted in processes of testing, trial production, collection, storage, transportation and analysis, making the properties of formation water not be reflected truly. This paper discusses identification methods and the data credibility evaluation method for formation water in oil and gas fields of petroliferous basins within China. The results of the study show that: (1) the identification methods of formation water include the basic methods of single factors such as physical characteristics, water composition characteristics, water type characteristics, and characteristic coefficients, as well as the comprehensive evaluation method of data credibility proposed on this basis, which mainly relies on the correlation analysis sodium chloride coefficient and desulfurization coefficient and combines geological background evaluation;(2) The basic identifying methods for formation water enable the preliminary identification of hydrochemical data and the preliminary screening of data on site, the proposed comprehensive method realizes the evaluation by classifying the CaCl2-type water into types A-I to A-VI and the NaHCO3-type water into types B-I to B-IV, so that researchers can make in-depth evaluation on the credibility of hydrochemical data and analysis of influencing factors;(3) When the basic methods are used to identify the formation water, the formation water containing anions such as CO_(3)^(2-), OH- and NO_(3)^(-), or the formation water with the sodium chloride coefficient and desulphurization coefficient not matching the geological setting, are all invaded with surface water or polluted by working fluid;(4) When the comprehensive method is used, the data credibility of A-I, A-II, B-I and B-II formation water can be evaluated effectively and accurately only if the geological setting analysis in respect of the factors such as formation environment, sampling conditions, condensate water, acid fluid, leaching of ancient weathering crust, and ancient atmospheric fresh water, is combined, although such formation water is believed with high credibility. 展开更多
关键词 oil and gas field hydrogeology formation water hydrochemical data data credibility evaluation method hydrochemical characteristic indicator influencing factor
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The Relationship Between Problem Features and Algorithm Evaluation Methods in Artificial Intelligence
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作者 Hao Wu Tongbang Wang Xinguo Yu 《教育技术与创新》 2025年第1期30-38,共9页
Algorithms are the primary component of Artificial Intelligence(AI).The algorithm is the process in AI that imitates the human mind to solve problems.Currently evaluating the performance of AI is achieved by evaluatin... Algorithms are the primary component of Artificial Intelligence(AI).The algorithm is the process in AI that imitates the human mind to solve problems.Currently evaluating the performance of AI is achieved by evaluating AI algorithms by metric scores on data sets.However the evaluation of algorithms in AI is challenging because the evaluation of the same type of algorithm has many data sets and evaluation metrics.Different algorithms may have individual strengths and weaknesses in evaluation metric scores on separate data sets,lacking the credibility and validity of the evaluation.Moreover,evaluation of algorithms requires repeated experiments on different data sets,reducing the attention of researchers to the research of the algorithms itself.Crucially,this approach to evaluating comparative metric scores does not take into account the algorithm’s ability to solve problems.And the classical algorithm evaluation of time and space complexity is not suitable for evaluating AI algorithms.Because classical algorithms input is infinite numbers,whereas AI algorithms input is a data set,which is limited and multifarious.According to the AI algorithm evaluation without response to the problem solving capability,this paper summarizes the features of AI algorithm evaluation and proposes an AI evaluation method that incorporates the problem-solving capabilities of algorithms. 展开更多
关键词 AI algorithm evaluation AI algorithm evaluation method intelligent research Problem Solving Capabilities
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Exploration of New Methods of Lightning Strike Risk Assessment in Wind Farms
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作者 Weixiang FENG Yijun LONG +3 位作者 Xiaoqing PAN Ruiliang CHEN Chunliang ZHANG Hui YANG 《Meteorological and Environmental Research》 2025年第1期44-48,共5页
In the past,the lightning strike risk assessment of wind farms mainly referred to the Lightning Protection Part 2:Risk Management(IEC 62305-2-2010)and the Lightning Protection of Wind Energy System(IEC 61400-24-2019)b... In the past,the lightning strike risk assessment of wind farms mainly referred to the Lightning Protection Part 2:Risk Management(IEC 62305-2-2010)and the Lightning Protection of Wind Energy System(IEC 61400-24-2019)based on protection angle method.In fact,the basic idea of the two is the same,that is,the source of the lightning fan is replaced by S1-S4 of the former lightning building with the latter ND-NDJ.According to the above method of wind farm evaluation,it has been proved that the practice can not achieve good results.Taking offshore wind farm as an example,this paper introduces a new method of establishing six evaluation indicators to determine the risk level according to the new technology and compliance principle of regional lightning protection(semi-circular method),which can be used for reference by wind farm technicians. 展开更多
关键词 Sea and land wind electric field Lightning strike risk assessment Compliance principle New evaluation method
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Method for Evaluating the Degrees of Land Use Sustainability of Mountainous County and its Application in Yunnan Province,China 被引量:10
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作者 YANG Zisheng LIU Yansui +2 位作者 TAO Wenxing XU Jingling ZHAO Qiaogui 《Journal of Mountain Science》 SCIE CSCD 2008年第2期98-112,共15页
The evaluation of sustainable land use is the key issue in the field of studying the sustainable land utilization. In general analysis, the sustainable land use is evaluated respectively from its ecological sustainabi... The evaluation of sustainable land use is the key issue in the field of studying the sustainable land utilization. In general analysis, the sustainable land use is evaluated respectively from its ecological sustainability, economic sustainability and social sustainability in China and other countries in recent years. Although this evaluation is an important work, it seems insufficient and hard to comprehensively reflect the whole degree of land use sustainability. Thus, to make up this deficiency, this paper brings forward the evaluation indexes, which make it possible to quantitatively reflect the whole degree of land use sustainability, namely, the concept of "degrees of overall land use sustainability" (Dos), and research and measurement development of the method of and calculation in Dos. Taking the evaluation of the degree of land use sustainability in county regions of Yunnan Province as the actual example for analysis, results are basically as follows: 1) The degree of land use sustainability (Dos) is the ration index to organically and systematically integrate the degree of ecological friendliness (DeF), the degree of economic viability (Dev) and the degree of social acceptability (Dsa), able to comprehensively reflect the whole sustainability degree of regional land use 2) Based on the value of Dos, the grading system and standard for the sustainability of land use may be established and totally divided into five grades, namely, the high-degree sustainability, middle-degree sustainability, low-degree sustainability, conditional sustainability and non-sustainability. Meanwhile, the standard for distinguishing sustainability grades has also been confirmed so as to determine the nature of sustainability degrees in different grades. This makes the possibility for the combination of nature determination with ration in research result and provides with the scientific guideline and decision-making gist for better implementation of sustainable land use strategy. 3) The practice in evaluation of sustainability degree in county regional land use in Yunnan shows that the value of the degree of land use sustainability (Dos) of whole Yunnan Province is only 58.39, belonging to the grade of low-degree sustainability. Two thirds of counties in the whole province represent the grade of "conditional sustainability" and "non-sustainability" in the sustainability of land use. Among these counties, 11.11 % shows "non- sustainability'. The lowest degree of land use sustainability appears especially in the middle plateau mountain region of Northeast Yunnan, where the value of Dos in most counties (districts) is below 40 %, belonging to the grade of "non-sustainability". The sustainability degree in the karst mountainous region in lower-middle plateau mountain region in Southeast Yunnan is generally low and the value of sustainability degree (Dos) in most of the counties (cities and districts) is below 55. The value of sustainability degree (Dos) in most of the counties (cities and districts) in the north, west, northwest and southwest parts of Yunnan is below 55. This article also analyzes the reasons of low degree of sustainability in land use in Yunnan and puts forward the countermeasures to increase the degree of sustainability in land use in the whole province. 展开更多
关键词 Land use degrees of overall sustainability evaluation method county level degrees of ecological friendliness degrees of economic viability degrees of social acceptability
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An electrochemical method for evaluating the resistance to cathodic disbondment of anti-corrosion coatings on buried pipelines 被引量:3
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作者 Chan Li Bei Cao Yinshun Wu 《Journal of University of Science and Technology Beijing》 CSCD 2007年第5期414-419,共6页
Methods for evaluating the resistance to cathodic disbondment (RCD) of anti-corrosion coatings on buried pipelines were reviewed. It is obvious that these traditional cathodic disbondment tests (CDT) have some dis... Methods for evaluating the resistance to cathodic disbondment (RCD) of anti-corrosion coatings on buried pipelines were reviewed. It is obvious that these traditional cathodic disbondment tests (CDT) have some disadvantages and the evaluated results are only simple figures and always rely on the subjective experience of the operator. A new electrochemical method for evaluating the RCD of coatings, that is, the potentiostatic evaluation method (PEM), was developed and studied. During potentiostatic anodic polarization testing, the changes of stable polarization current of specimens before and after cathodic disbonding (CD) were measured, and the degree of cathodic disbondment of the coating was quantitatively evaluated, among which the equivalent cathodic disbonded distance AD was suggested as a parameter for evaluating the RCD. A series of testing parameters of the PEM were determined in these experiments. 展开更多
关键词 buried pipeline anti-corrosion coating resistance to cathodic disbondment (RCD) potentiostatic evaluation method(PEM) fusion bonded epoxy (FBE) three-layer polyethylene (3PE)
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A Quantitative Method for Evaluating the Transporting Capacity of Oil-Source Faults in Shallow Formation of Oil-Rich Sags 被引量:4
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作者 JIANG Youlu ZHAO Kai +1 位作者 LIU Jingdong LU Xueying 《Acta Geologica Sinica(English Edition)》 CAS CSCD 2018年第4期1678-1679,共2页
Objective Oil-source faults have an important effect on reservoir formation and distribution in shallow formations with non- hydrocarbon generation in oil-rich fault-related basins (Jiang Youlu et al., 2015). Howev... Objective Oil-source faults have an important effect on reservoir formation and distribution in shallow formations with non- hydrocarbon generation in oil-rich fault-related basins (Jiang Youlu et al., 2015). However, the fault transporting capacity cannot be evaluated quantitatively at present. Taking the Zhanhua Sag in the Bohai Bay Basin as an example, this work analyzed the factors influencing the transporting capacity of the oil-source faults and proposed a quantitative method for evaluating their transporting capacity. 展开更多
关键词 A Quantitative method for evaluating the Transporting Capacity of Oil-Source Faults in Shallow Formation of Oil-Rich Sags
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Screening of Long Cowpea[Vigna unguiculata(L.)Walp.ssp.sesquipedialis]Varieties in Autumn in Hunan and Comparison of Various Comprehensive Evaluation Methods 被引量:1
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作者 Lin HUANG Zhibing CHEN +6 位作者 Wan JIANG Xincheng SUN Zhongwu ZHANG Jie KANG Lianyong YANG Weiping CHEN Yuanqun PENG 《Plant Diseases and Pests》 2024年第5期33-39,共7页
[Objectives]The paper was to screen new varieties of long cowpea that are suitable for autumn cultivation in Hunan,as well as to develop a comprehensive evaluation method to assess their adaptability and performance.[... [Objectives]The paper was to screen new varieties of long cowpea that are suitable for autumn cultivation in Hunan,as well as to develop a comprehensive evaluation method to assess their adaptability and performance.[Methods]A total of 48 long cowpea varieties were introduced,and a range of comprehensive evaluation methods was employed to assess these varieties through the collection and analysis of field data.[Results]The square Euclidean distance of 14 allowed for the classification of all varieties into eight distinct groups.Groups II,III,and V belong to the autumn dominant group within this region,while groups I and VIII belong to the intermediate group.Additionally,groups IV,VI,and VII belong to the autumn inferior group in this area.Through a comparative analysis of various comprehensive evaluation methods,it was determined that the common factor comprehensive evaluation,grey correlation method,and fuzzy evaluation method were appropriate for application in the selection of long cowpea varieties.Furthermore,the evaluation outcomes were largely consistent with the cluster pedigree diagram.[Conclusions]Through comprehensive index method,ten varieties demonstrating superior performance in autumn cultivation have been identified,including C20,C42,C29,C40,C3,C14,C18,C25,C15,and C47.The selected varieties exhibit several advantageous traits,such as a reduced growth duration,a lower position of initial flower nodes,a decreased number of branches,predominantly green young pods,elongated pod strips,thicker pod structures,an increased number of pods per plant,and higher overall yields.These characteristics render them particularly valuable for extensive cultivation. 展开更多
关键词 Long cowpea Variety SCREENING Cluster analysis Comprehensive evaluation method
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A Novel Approach for Rapid Evaluating Cavitation Erosion Resistance of Metallic Materials
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作者 Yu Li Zhenbo Qin +5 位作者 Xiaoyang Du Da-Hai Xia Zepeng Gao Yiwen Zhang Zhong Wu Wenbin Hu 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2024年第7期1231-1237,共7页
For the evaluation of cavitation erosion resistance of metallic materials,it has always been a time-consuming technical problem.This paper innovatively proposed a parameter named cavitation hardening rate to character... For the evaluation of cavitation erosion resistance of metallic materials,it has always been a time-consuming technical problem.This paper innovatively proposed a parameter named cavitation hardening rate to characterize the plastic deformation and work hardening behavior of metallic materials during the cavitation process and then found a positive correlation between cavitation hardening rate and strain hardening index.Finally,the relationship between cavitation volume loss and strain hardening index was obtained,and a simple and rapid evaluation method for cavitation erosion resistance was established. 展开更多
关键词 Cavitation erosion Evaluation method Cavitation hardening rate Volume loss
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An ecological value evaluation method based on ecological restoration:A case study of the Saihanba Mechanized Forest Farm in Chengde City
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作者 Chao Li Feng Yang +1 位作者 Maomao Yan Ying Qu 《Chinese Journal of Population,Resources and Environment》 2024年第4期493-500,共8页
As China continues to develop its ecological civilization,it is crucial to quantitatively assess the ecological value to understand its potential impact on regional sustainable development.While previous studies have ... As China continues to develop its ecological civilization,it is crucial to quantitatively assess the ecological value to understand its potential impact on regional sustainable development.While previous studies have highlighted the importance of ecological value,they have not fully reflected the value of ecological restoration work or considered social costs and benefits,lacking a people-centered approach.Hence,this study analyzes the essence of ecological value from the perspective of sustainable development.By studying emblematic ecological restoration areas such as the Saihanba Mechanized Forest Farm in Chengde City,it aims to identify the significance of ecological restoration efforts in enhancing regional sustainable development capacity.The results underscore the necessity of comprehensively considering the value chain from ecological construction to ecological output,highlighting the value of ecological restoration in the ecological construction process as well as the well-being of people in the ecological output process.This approach assigns more economic and humanistic attributes to ecological value,thereby better serving the development of ecological restoration areas. 展开更多
关键词 Ecological value Ecological restoration Evaluation methods Sustainable development Saihanba Mechanized Forest Farm
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Evaluating Communicative Teaching Method With Consideration of Psycholinguistics
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作者 Ren Hui(English Department Suzhou Teachers’ College,Suzhou Anhui 234000) 《宿州师专学报》 2001年第2期99-101,103,共4页
  Communicative language teaching has been in vogue in the past ten years. Being a language teaching method, it is closely related to linguistics, sociology, educeational theories and so on, psycholinguistics, a bra...   Communicative language teaching has been in vogue in the past ten years. Being a language teaching method, it is closely related to linguistics, sociology, educeational theories and so on, psycholinguistics, a branch of linguistics focusing on the mental processes involved in human being's language acquisition and production, play a most important role in the study of language teaching, including communicative language teaching (CLT) of course. In this paper the writer will evaluate the CLT with the consideration of psycholinguistics to what extent CLT is helpful for second language teaching and learning.…… 展开更多
关键词 evaluating Communicative Teaching method With Consideration of Psycholinguistics
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A STUDY ON NONINVASIVE METHOD FOR MEATURING AND EVALUATING CARDIAC RESERVE OF ATHLETES
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作者 Guochuan Liu(Bo-Jing MedicaI Informatics Institute, Chongqing University, Chongqing 400044, China) 《Chinese Journal of Biomedical Engineering(English Edition)》 1999年第3期61-62,共2页
关键词 IEEE A STUDY ON NONINVASIVE method FOR MEATURING AND evaluating CARDIAC RESERVE OF ATHLETES
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Evaluation and Intervention Methods for Patients with Prediabetes of Different Phenotypes
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作者 Zhenghui Zha Yuli Zhang Songtao Wang 《Journal of Clinical and Nursing Research》 2024年第12期350-356,共7页
Prediabetes is a heterogeneous condition,encompassing various pathological phenotypes such as hyperinsulinemia,tissue-specific insulin resistance(IR),systemic IR,andβ-cell dysfunction.A significant proportion of indi... Prediabetes is a heterogeneous condition,encompassing various pathological phenotypes such as hyperinsulinemia,tissue-specific insulin resistance(IR),systemic IR,andβ-cell dysfunction.A significant proportion of individuals with prediabetes remain undiagnosed.Furthermore,although lifestyle interventions have demonstrated efficacy in improving prediabetic conditions,some individuals with prediabetes progress to type 2 diabetes mellitus.This study aims to summarize effective evaluation methods for identifying distinct pathological phenotypes of prediabetes and targeted lifestyle intervention strategies to mitigate the progression from prediabetes to diabetes. 展开更多
关键词 PREDIABETES Type 2 diabetes mellitus Evaluation methods Lifestyle intervention
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Application of Choquet Integral-Importance-Performance Analysis and TOPSIS Methods in Approaching the Preference Factors of Calligraphy and Seal Engraving Imagery
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作者 Yu Hsuan Chang Jiann Sheng Jiang Min Min Lin 《Journal of Contemporary Educational Research》 2024年第5期276-288,共13页
Classical Chinese characters,presented through calligraphy,seal engraving,or painting,can exhibit different aesthetics and essences of Chinese characters,making them the most important asset of the Chinese people.Call... Classical Chinese characters,presented through calligraphy,seal engraving,or painting,can exhibit different aesthetics and essences of Chinese characters,making them the most important asset of the Chinese people.Calligraphy and seal engraving,as two closely related systems in traditional Chinese art,have developed through the ages.Due to changes in lifestyle and advancements in modern technology,their original functions of daily writing and verification have gradually diminished.Instead,they have increasingly played a significant role in commercial art.This study utilizes the Evaluation Grid Method(EGM)and the Analytic Hierarchy Process(AHP)to research the key preference factors in the application of calligraphy and seal engraving imagery.Different from the traditional 5-point equal interval semantic questionnaire,this study employs a non-equal interval semantic questionnaire with a golden ratio scale,distinguishing the importance ratio of adjacent semantic meanings and highlighting the weighted emphasis on visual aesthetics.Additionally,the study uses Importance-Performance Analysis(IPA)and Technique for Order Preference by Similarity to Ideal Solution(TOPSIS)to obtain the key preference sequence of calligraphy and seal engraving culture.Plus,the Choquet integral comprehensive evaluation is used as a reference for IPA comparison.It is hoped that this study can provide cultural imagery references and research methods,injecting further creativity into industrial design. 展开更多
关键词 Evaluation Grid method Analytic Hierarchy Process CALLIGRAPHY Seal engraving Importance-Performance Analysis Choquet integral TOPSIS
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Application of Fuzzy Comprehensive Evaluation Method Based on Entropy Weight to Evaluate Pond Water Quality 被引量:1
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作者 吴会民 张韦 +4 位作者 梁传辉 樊振中 谢刚 高勇 缴建华 《Agricultural Science & Technology》 CAS 2012年第3期664-668,共5页
[Objective] This study was to provide references for the evaluation of water quality in aquaculture ponds by evaluating the pond water quality using fuzzy comprehensive evaluation method based on entropy weight. [Meth... [Objective] This study was to provide references for the evaluation of water quality in aquaculture ponds by evaluating the pond water quality using fuzzy comprehensive evaluation method based on entropy weight. [Method] The fuzzy compre- hensive evaluation method based on entropy weight was used to evaluate the water quality in the ponds with Ukraine scale carp (Cyprinus carpio) as the main cultivated fish. The average size of the fish was 71.4 g/ind, and totally three groups of pond were set with the population density of 6 000, 9 000, 12 000 ind/hm2. [Result] According to the GB3838-2002 Environmental Quality Standards for Surface Water of China, the water quality of 6 000 ind/hm2 group was Grade I, and the water quality of 9 000 and 12 000 ind/hm2 were Grade V. [Conclusion] With the increasing of feeding density, the pond water quality would worsen, however, there is no difference on water quality between 9 000 and 12 000 ind/hm2 groups. 展开更多
关键词 Water quality Aquaculture pond Fuzzy comprehensive evaluation method Entropy weight
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Study on the evaluation index system and evaluation method for self-elevating drilling unit design 被引量:1
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作者 王运龙 纪卓尚 《Journal of Marine Science and Application》 2009年第1期46-52,共7页
In the process of designing self-elevating drilling unit, it is important, yet complicated, to use comparison and filtering to select the optimum scheme from the feasible ones. In this research, an index system and me... In the process of designing self-elevating drilling unit, it is important, yet complicated, to use comparison and filtering to select the optimum scheme from the feasible ones. In this research, an index system and methodology for the evaluation of self-elevating drilling unit was proposed. Based on this, a multi-objective combinatorial optimization model was developed, using the improved grey relation Analysis (GRA), in which the analytic hierarchy process (AHP) was used to determine the weights of the evaluating indices. It considered the connections within the indices, reflecting the objective nature of things, and also considered the subjective interests of ship owners and the needs of designers. The evaluation index system and evaluation method can be used in the selection of an optimal scheme and advanced assessment. A case study shows the index system and evaluation method are scientific, reasonable, and easy to put into practice. At the same time, such an evaluation index system and evaluation method will be helpful for making decisions for other mobile platforms. 展开更多
关键词 self-elevating drilling unit evaluation index system evaluation method grey relation analysis (GRA) analytic hierarchy process (AHP)
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Lifetime Evaluating and the Effects of Operation Conditions on Automotive Fuel Cells 被引量:3
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作者 PEI Pucheng YUAN Xing +2 位作者 LI Pengcheng CHAO Pengxiang CHANG Qianfei 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2010年第1期66-71,共6页
Lifetime isone of the important indicators of automotive proton exchange membrane fuel cells. People used to evaluate the lifetime of vehicular fuel cells by laboratory tests or road tests that usually take thousands ... Lifetime isone of the important indicators of automotive proton exchange membrane fuel cells. People used to evaluate the lifetime of vehicular fuel cells by laboratory tests or road tests that usually take thousands hours even years. In order to achieve a rapid evaluation technique and to seek lifetime extension methods, a lifetime calculation formation was drawn out in consideration of the vehicle driving cycle and the working condition factors. Bench experiments were individually carried out on two fuel-cell stacks same as ones applied on vehicle, and the performance decay rates of the two stacks were obtained under four operation conditions of changing load cycle, start-stop cycle, idling and heavy load. As a result, the predicted lifetimes rather conform to the actual running status in road test. And the research on the fuel cell performance decay rates under different load conditions was also done. Consequently, an unexpected finding was discovered that operating under micro-current has an effect on recovering fuel cell performance. The vehicle fuel cell rapid assessment method only requires four laboratory tests of driving cycle, load cycle, idle operating conditions and heavy load conditions, and the whole process merely lasts less than 250 h. These experimental results can be used to predict the vehicular fuel cell lifetimes on various utility models or driving cycles, therefore to optimize the application model to prolong the fuel cell lifetime. Actually in the experiment, it has already been proved successfully that the fuel cell lifetime could be extended from 1 100 h to 2 600 h by optimizing operating mode. The quick evaluation method is helpful to develop extended life fuel cell and to deplete fuel cell for a longer time. 展开更多
关键词 Proton exchange membrane fuel cell fuel cell durability lifetime evaluating method operation conditions melioration.
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Scale Effects and a Method for Similarity Evaluation in Micro Electrical Discharge Machining 被引量:1
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作者 LIU Qingyu ZHANG Qinhe +3 位作者 WANG Kan ZHU Guang FU Xiuzhuo ZHANG Jianhua 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第6期1193-1199,共7页
Electrical discharge machining(EDM) is a promising non-traditional micro machining technology that offers a vast array of applications in the manufacturing industry. However, scale effects occur when machining at th... Electrical discharge machining(EDM) is a promising non-traditional micro machining technology that offers a vast array of applications in the manufacturing industry. However, scale effects occur when machining at the micro-scale, which can make it difficult to predict and optimize the machining performances of micro EDM. A new concept of "scale effects" in micro EDM is proposed, the scale effects can reveal the difference in machining performances between micro EDM and conventional macro EDM. Similarity theory is presented to evaluate the scale effects in micro EDM. Single factor experiments are conducted and the experimental results are analyzed by discussing the similarity difference and similarity precision. The results show that the output results of scale effects in micro EDM do not change linearly with discharge parameters. The values of similarity precision of machining time significantly increase when scaling-down the capacitance or open-circuit voltage. It is indicated that the lower the scale of the discharge parameter, the greater the deviation of non-geometrical similarity degree over geometrical similarity degree, which means that the micro EDM system with lower discharge energy experiences more scale effects. The largest similarity difference is 5.34 while the largest similarity precision can be as high as 114.03. It is suggested that the similarity precision is more effective in reflecting the scale effects and their fluctuation than similarity difference. Consequently, similarity theory is suitable for evaluating the scale effects in micro EDM. This proposed research offers engineering values for optimizing the machining parameters and improving the machining performances of micro EDM. 展开更多
关键词 Electrical Discharge Machining (EDM) micro EDM Scale effect Similarity theory Similarity evaluating method
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Optimization of convolutional neural networks for predicting water pollutants using spectral data in the middle and lower reaches of the Yangtze River Basin,China
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作者 ZHANG Guohao LI Song +3 位作者 WANG Cailing WANG Hongwei YU Tao DAI Xiaoxu 《Journal of Mountain Science》 2025年第8期2851-2869,共19页
Developing an accurate and efficient comprehensive water quality prediction model and its assessment method is crucial for the prevention and control of water pollution.Deep learning(DL),as one of the most promising t... Developing an accurate and efficient comprehensive water quality prediction model and its assessment method is crucial for the prevention and control of water pollution.Deep learning(DL),as one of the most promising technologies today,plays a crucial role in the effective assessment of water body health,which is essential for water resource management.This study models using both the original dataset and a dataset augmented with Generative Adversarial Networks(GAN).It integrates optimization algorithms(OA)with Convolutional Neural Networks(CNN)to propose a comprehensive water quality model evaluation method aiming at identifying the optimal models for different pollutants.Specifically,after preprocessing the spectral dataset,data augmentation was conducted to obtain two datasets.Then,six new models were developed on these datasets using particle swarm optimization(PSO),genetic algorithm(GA),and simulated annealing(SA)combined with CNN to simulate and forecast the concentrations of three water pollutants:Chemical Oxygen Demand(COD),Total Nitrogen(TN),and Total Phosphorus(TP).Finally,seven model evaluation methods,including uncertainty analysis,were used to evaluate the constructed models and select the optimal models for the three pollutants.The evaluation results indicate that the GPSCNN model performed best in predicting COD and TP concentrations,while the GGACNN model excelled in TN concentration prediction.Compared to existing technologies,the proposed models and evaluation methods provide a more comprehensive and rapid approach to water body prediction and assessment,offering new insights and methods for water pollution prevention and control. 展开更多
关键词 Water pollutants Convolutional neural networks Data augmentation Optimization algorithms Model evaluation methods Deep Learning
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