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Research on a TOPSIS energy efficiency evaluation system for crude oil gathering and transportation systems based on a GA-BP neural network
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作者 Xue-Qiang Zhang Qing-Lin Cheng +2 位作者 Wei Sun Yi Zhao Zhi-Min Li 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期621-640,共20页
As the main link of ground engineering,crude oil gathering and transportation systems require huge energy consumption and complex structures.It is necessary to establish an energy efficiency evaluation system for crud... As the main link of ground engineering,crude oil gathering and transportation systems require huge energy consumption and complex structures.It is necessary to establish an energy efficiency evaluation system for crude oil gathering and transportation systems and identify the energy efficiency gaps.In this paper,the energy efficiency evaluation system of the crude oil gathering and transportation system in an oilfield in western China is established.Combined with the big data analysis method,the GA-BP neural network is used to establish the energy efficiency index prediction model for crude oil gathering and transportation systems.The comprehensive energy consumption,gas consumption,power consumption,energy utilization rate,heat utilization rate,and power utilization rate of crude oil gathering and transportation systems are predicted.Considering the efficiency and unit consumption index of the crude oil gathering and transportation system,the energy efficiency evaluation system of the crude oil gathering and transportation system is established based on a game theory combined weighting method and TOPSIS evaluation method,and the subjective weight is determined by the triangular fuzzy analytic hierarchy process.The entropy weight method determines the objective weight,and the combined weight of game theory combines subjectivity with objectivity to comprehensively evaluate the comprehensive energy efficiency of crude oil gathering and transportation systems and their subsystems.Finally,the weak links in energy utilization are identified,and energy conservation and consumption reduction are improved.The above research provides technical support for the green,efficient and intelligent development of crude oil gathering and transportation systems. 展开更多
关键词 Crude oil gathering and transportation system GA-BP neural network Energy efficiency evaluation TOPSIS evaluation method Energy saving and consumption reduction
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Myelin histology:a key tool in nervous system research
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作者 Óscar Darío García-García Víctor Carriel Jesús Chato-Astrain 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第2期277-281,共5页
The myelin sheath is a lipoprotein-rich,multilayered structure capable of increasing conduction velocity in central and peripheral myelinated nerve fibers.Due to the complex structure and composition of myelin,various... The myelin sheath is a lipoprotein-rich,multilayered structure capable of increasing conduction velocity in central and peripheral myelinated nerve fibers.Due to the complex structure and composition of myelin,various histological techniques have been developed over the centuries to evaluate myelin under normal,pathological or experimental conditions.Today,methods to assess myelin integrity or content are key tools in both clinical diagnosis and neuroscience research.In this review,we provide an updated summary of the composition and structure of the myelin sheath and discuss some histological procedures,from tissue fixation and processing techniques to the most used and practical myelin histological staining methods.Considering the lipoprotein nature of myelin,the main features and technical details of the different available methods that can be used to evaluate the lipid or protein components of myelin are described,as well as the precise ultrastructural techniques. 展开更多
关键词 fluorescence microscopy HISTOLOGY light microscopy lipid histochemistry metallographic techniques myelin histochemistry myelin immunohistochemistry myelin structure&composition myelin ultrastructural evaluation tissue fixation&processing
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Efficacy and safety of Yangxinshi tablet for chronic heart failure:A systematic review and meta-analysis
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作者 Sheng-Hua Lu Yun-Feng Yu +2 位作者 Si-Si Dai Ya-Qi Hu Jian-He Liu 《World Journal of Clinical Cases》 SCIE 2024年第13期2218-2230,共13页
BACKGROUND The specific benefits of Yangxinshi tablet(YXST)in the treating chronic heart failure(CHF)remain uncertain.AIM To systematically evaluate the efficacy and safety of YXST in the treatment of CHF.METHODS Rand... BACKGROUND The specific benefits of Yangxinshi tablet(YXST)in the treating chronic heart failure(CHF)remain uncertain.AIM To systematically evaluate the efficacy and safety of YXST in the treatment of CHF.METHODS Randomized controlled trials(RCTs)investigating YXST for CHF treatment were retrieved from eight public databases up to November 2023.Meta-analyses of the included clinical studies were conducted using Review Manager 5.3.RESULTS Twenty RCTs and 1845 patients were included.The meta-analysis results showed that the YXST combination group,compared to the conventional drug group,significantly increased the clinical efficacy rate by 23%[relative risk(RR)=1.23,95%CI:1.17-1.29],(P<0.00001),left ventricular ejection fraction by 6.69%[mean difference(MD)=6.69,95%CI:4.42-8.95,P<0.00001]and 6-min walk test by 49.82 m(MD=49.82,95%C:38.84-60.80,P<0.00001),and reduced N-terminal pro-Btype natriuretic peptide by 1.03 ng/L[standardized MD(SMD)=-1.03,95%CI:-1.32 to-0.74,P<0.00001],brain natriuretic peptide by 80.95 ng/L(MD=-80.95,95%CI:-143.31 to-18.59,P=0.01),left ventricular end-diastolic diameter by 3.92 mm(MD=-3.92,95%CI:-5.06 to-2.78,P<0.00001),and left ventricular endsystolic diameter by 4.34 mm(MD=-4.34,95%CI:-6.22 to-2.47,P<0.00001).Regarding safety,neither group reported any serious adverse events during treatment(RR=0.54,95%CI:0.15-1.90,P=0.33).In addition,Egger's test results indicated no significant publication bias(P=0.557).CONCLUSION YXST effectively improves clinical symptoms and cardiac function in patients with CHF while maintaining a favorable safety profile,suggesting its potential as a therapeutic strategy for CHF. 展开更多
关键词 Yangxinshi tablet Chronic heart failure Cardiac function systematic evaluation META-ANALYSIS
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Carbon efficiency evaluation method for urban energy system with multiple energy complementary
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作者 Xianan Jiao Jiekang Wu +1 位作者 Yunshou Mao Mengxuan Yan 《Global Energy Interconnection》 EI CSCD 2024年第2期142-154,共13页
Urban energy systems(UESs)play a pivotal role in the consumption of clean energy and the promotion of energy cascade utilization.In the context of the construction and operation strategy of UESs with multiple compleme... Urban energy systems(UESs)play a pivotal role in the consumption of clean energy and the promotion of energy cascade utilization.In the context of the construction and operation strategy of UESs with multiple complementary energy resources,a comprehensive assessment of the energy efficiency is of paramount importance.First,a multi-dimensional evaluation system with four primary indexes of energy utilization,environmental protection,system operation,and economic efficiency and 21 secondary indexes is constructed to comprehensively portray the UES.Considering that the evaluation system may contain a large number of indexes and that there is overlapping information among them,an energy efficiency evaluation method based on data processing,dimensionality reduction,integration of combined weights,and gray correlation analysis is proposed.This method can effectively reduce the number of calculations and improve the accuracy of energy efficiency assessments.Third,a demonstration project for a UES in China is presented.The energy efficiency of each scenario is assessed using six operational scenarios.The results show that Scenario 5,in which parks operate independently and investors build shared energy-storage equipment,has the best results and is best suited for green and low-carbon development.The results of the comparative assessment methods show that the proposed method provides a good energy efficiency assessment.This study provides a reference for the optimal planning,construction,and operation of UESs with multiple energy sources. 展开更多
关键词 Urban energy systems(UESs) Multiple energy complementary system Carbon efficiency evaluation Data downscaling Subjective and objective weight Gray correlation analysis
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Spatio-temporal Evaluation of Multi-scale Cultivated Land System Resilience in Black Soil Region from 2000 to 2019:A Case Study of Liaoning Province,Northeast China
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作者 WANG Yue JIANG Yuting ZHU Guoxu 《Chinese Geographical Science》 SCIE CSCD 2024年第1期168-180,共13页
It is of great significance to systematically analyze the cultivated land system resilience(CLSR) for the black soil protection and national food security.The CLSR is impacted by planting structure adjustment and cult... It is of great significance to systematically analyze the cultivated land system resilience(CLSR) for the black soil protection and national food security.The CLSR is impacted by planting structure adjustment and cultivated land quality decline,posing major hidden dangers to food security.It is urgent to evaluate the CLSR at multiple spatio-temporal scales.This study took Liaoning Province in the black soil region of Northeast China as an example.Based on the resilience theory,this study constructed the CLSR evaluation system from the input-feedback perspective at the provincial-scale and the city-scale,and used the rank-sum ratio comprehensive evaluation method(RSR) to analyze the key influencing factors of CLSR in Liaoning Province and its 14 cities from 2000 to 2019.The results showed that:1) the time series changes of CLSR at the provincial-scale and the city-scale in Liaoning Province were similar,both showing an increasing trend.2) The CLSR in Liaoning Province presented a spatial pattern of ‘high in the west and low in the east’ at the city-scale.3) There were seven and six main influencing factors of CLSR at the provincial-scale and the city-scale,respectively.In addition to the net income per capita of rural households,other influencing factors of CLSR were different at the provincial-scale and the city-scale.The feedback factors were dominant at the provincial-scale,and the input factors and feedback factors were dominant at the city-scale.The results could provide a reference for the utilization of black soil and draw on the experience of regional agricultural planning and adjustment. 展开更多
关键词 cultivated land system resilience(CLSR) rank-sum ratio comprehensive evaluation(RSR) multi-scales influencing factors black soil region Liaoning Province China
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A preliminary site selection system for underground hydrogen storage in salt caverns and its application in Pingdingshan,China
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作者 Liangchao Huang Yanli Fang +6 位作者 Zhengmeng Hou Yachen Xie Lin Wu Jiashun Luo Qichen Wang Yilin Guo Wei Sun 《Deep Underground Science and Engineering》 2024年第1期117-128,共12页
Large‐scale underground hydrogen storage(UHS)provides a promising method for increasing the role of hydrogen in the process of carbon neutrality and energy transition.Of all the existing storage deposits,salt caverns... Large‐scale underground hydrogen storage(UHS)provides a promising method for increasing the role of hydrogen in the process of carbon neutrality and energy transition.Of all the existing storage deposits,salt caverns are recognized as ideal sites for pure hydrogen storage.Evaluation and optimization of site selection for hydrogen storage facilities in salt caverns have become significant issues.In this article,the software CiteSpace is used to analyze and filter hot topics in published research.Based on a detailed classification and analysis,a“four‐factor”model for the site selection of salt cavern hydrogen storage is proposed,encompassing the dynamic demands of hydrogen energy,geological,hydrological,and ground factors of salt mines.Subsequently,20 basic indicators for comprehensive suitability grading of the target site were screened using the analytic hierarchy process and expert survey methods were adopted,which provided a preliminary site selection system for salt cavern hydrogen storage.Ultimately,the developed system was applied for the evaluation of salt cavern hydrogen storage sites in the salt mines of Pingdingshan City,Henan Province,thereby confirming its rationality and effectiveness.This research provides a feasible method and theoretical basis for the site selection of UHS in salt caverns in China. 展开更多
关键词 analytic hierarchy process(AHP) evaluation index hydrogen storage salt cavern site selection
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On Evaluating University Teachers’ Morality and Ethics in the New Era
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作者 LIU Qiu-fen 《Journal of Literature and Art Studies》 2024年第1期92-94,共3页
University teachers play an important role in promoting moral and political education among university students.Regular and long-term construction of teachers’morality and ethics will contribute to the success of the... University teachers play an important role in promoting moral and political education among university students.Regular and long-term construction of teachers’morality and ethics will contribute to the success of the fundamental task of cultivating talents.The present study proposes that due to the multiple identities of university teachers,it is necessary to evaluate the construction of teachers’morality and ethics in terms of what to evaluate and how to evaluate?It is expected that the attempt will provide useful guidance for the construction of university teachers’morality and ethics. 展开更多
关键词 university teachers morality and ethics construction EVALUATION
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Evaluation of the Reliability of a System: Approach by Monte Carlo Simulation and Application
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作者 Aslain Brisco Ngnassi Djami Jean Bosco Samon +4 位作者 Boukar Ousman Ulrich Ngnassi Nguelcheu Wolfgang Nzié Guy Edgar Ntamack Bienvenu Kenmeugne 《Open Journal of Applied Sciences》 2024年第3期721-739,共19页
The objective of this paper is to evaluate the reliability of a system in its different states (absence of failures, partial failure and total failure) and to propose actions to improve this reliability by an approach... The objective of this paper is to evaluate the reliability of a system in its different states (absence of failures, partial failure and total failure) and to propose actions to improve this reliability by an approach based on Monte Carlo simulation. It consists of a probabilistic evaluation based on Markov Chains. In order to achieve this goal, the functionalities of Markov Chains and Monte Carlo simulation steps are deployed. The application is made on a production system. . 展开更多
关键词 EVALUATION RELIABILITY Monte Carlo Markov Chain
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Exploration and Research on Textbook Quality Evaluation Index System Based on Engineering Major in Higher Education
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作者 Xiaoyang Yue Yanqiong Wu 《Journal of Contemporary Educational Research》 2024年第3期1-6,共6页
The report of the Chinese 20th National Congress put forward“strengthening the construction and management of textbooks”for the first time,which indicates the importance of textbook construction and highlights the v... The report of the Chinese 20th National Congress put forward“strengthening the construction and management of textbooks”for the first time,which indicates the importance of textbook construction and highlights the vital position of textbooks in the overall development of the country.From the perspective of textbook quality,and based on the research and analysis of the policy requirements and current evaluation indicators of higher education textbooks,this paper establishes the textbook quality evaluation index system composed of basic indicators and evaluation indicators.This system is based on the principles of science,comprehensiveness,operability,and target-oriented approach.It provides a relatively scientific,objective,and fair reference system for the management and evaluation of textbooks. 展开更多
关键词 Textbooks Evaluation index system Higher education Engineering major
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Research on the Evaluation System of Community Daycare Center Planning and Implementation from the Perspective of Subject-Object Relationships
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作者 Tijin Gui 《Journal of Architectural Research and Development》 2024年第3期117-127,共11页
Through literature review,we found that evaluations of urban planning implementation often focus narrowly on either the subject(stakeholders)or the object(projects),while micro-level aspects such as site selection and... Through literature review,we found that evaluations of urban planning implementation often focus narrowly on either the subject(stakeholders)or the object(projects),while micro-level aspects such as site selection and construction are primarily considered within the context of planning implementation.There is insufficient research on the evaluation of implementation.Community daycare centers play a crucial role in the community home care model,yet there is relatively little research on their usage efficiency,satisfaction levels,and spatial evaluation of planning implementation.Based on the theoretical understanding of the human environment,including the subject,object,and their interactions,an evaluation system for the planning and implementation of community day care centers was constructed,incorporating subjective evaluation,objective evaluation,and comparative analysis. 展开更多
关键词 Subject-object relationship Daycare center Planning implementation Evaluation system
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Research on the Index System of Old Neighborhood Renovation Based on Green Building Evaluation Standard
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作者 Yufei Que 《Journal of Architectural Research and Development》 2024年第3期140-146,共7页
With the advancement of the transformation,the contradiction between the residents’demand for a better living environment and the convenience of living in the settlements comes to the fore.Effective identification,or... With the advancement of the transformation,the contradiction between the residents’demand for a better living environment and the convenience of living in the settlements comes to the fore.Effective identification,organic integration,timely adoption,and correct decision-making for the transformation of old neighborhoods are pressing issues in the transformation of old neighborhoods.Therefore,this paper takes the green building evaluation standards of various countries as the research basis and support for the construction of the transformation strategy of old neighborhoods.Through the collection and comparative analysis of the indicators of green building evaluation standards,the index system of transformation is formed,and it also provides a certain foundation for the subsequent related research. 展开更多
关键词 Old neighborhoods Green building evaluation standards RENOVATION CRITERIA
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Course Design and Evaluation System Construction Under the STEM Education Mode
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作者 Jiaxiang Chen 《Journal of Contemporary Educational Research》 2024年第4期74-79,共6页
With the rapid development of information technology,Science,Technology,Engineering,and Mathematics(STEM)education,as a crucial model for nurturing innovative talents,is gaining increasing attention.However,challenges... With the rapid development of information technology,Science,Technology,Engineering,and Mathematics(STEM)education,as a crucial model for nurturing innovative talents,is gaining increasing attention.However,challenges such as insufficient resources and a lack of diversity in teaching methods exist in its implementation.Against this backdrop,this article conducts an in-depth analysis of course design and evaluation system construction under the STEM education model.The aim is to explore effective teaching strategies and diversified evaluation methods,with the ultimate goal of enhancing the quality of education and cultivating students’comprehensive problem-solving skills. 展开更多
关键词 STEM education Course design Evaluation system
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Exploration of the “Four-Three-Four” Internship and Training Mode in Higher Vocational Colleges Under the Modern Vocational Education System
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作者 Jifeng Liu Na Han +2 位作者 Xiaojiao Li Jing Wang Xuezhen Feng 《Journal of Contemporary Educational Research》 2024年第3期111-117,共7页
This article mainly introduces the innovative internship and training model of vocational colleges,including five aspects such as“four-party collaboration,three-stage progression,four-way integration,value-added eval... This article mainly introduces the innovative internship and training model of vocational colleges,including five aspects such as“four-party collaboration,three-stage progression,four-way integration,value-added evaluation,and double selection and promotion.”The model aims to improve students’practical skills and professional quality to better adapt to market demand and social development.The article also presents the prospects of the future internship and training model,including strengthening cooperation and communication with industry enterprises,focusing on students’personalized development and practical skill cultivation,and establishing a scientific and objective evaluation and feedback mechanism. 展开更多
关键词 Four-party collaboration Three-stage progression Four-way integration Value-added evaluation Double selection and promotion
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Development of an Information-Based Leadership Evaluation Index System for School Management Teams:A Comprehensive Approach
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作者 Wei Li Fang Liu 《Journal of Contemporary Educational Research》 2024年第4期35-40,共6页
In the context of educational informatization reform,there are many uncertain factors in the process of education development.To optimize the educational environment so that it can be effectively combined with informa... In the context of educational informatization reform,there are many uncertain factors in the process of education development.To optimize the educational environment so that it can be effectively combined with information technology,teachers need to change their teaching ideas,strengthen the school’s own adaptability to informatization,and promote the development of informatization construction in schools.As a branch of information leadership,the management team should establish an evaluation index system for information leadership in order to ensure the construction of school informatization,so as to provide a boost for the integration of school resources and information technology.Based on the overview and connotation of information-based leadership of the management team,this paper explores the construction of an evaluation index system of information-based leadership of the school management team,aiming to provide references for the research of relevant personnel in the future. 展开更多
关键词 School management team Information-based leadership Evaluation index system
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Analytical method for evaluating stress field in casing-cement-formation system of oil/gas wells 被引量:6
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作者 Wei LIU Baohua YU Jingen DENG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2017年第9期1273-1294,共22页
In this paper, we present an analytical method for evaluating the stress field within a casing-cement-formation system of oil/gas wells under anisotropic in-situ stresses in the rock formation and uniform pressure wit... In this paper, we present an analytical method for evaluating the stress field within a casing-cement-formation system of oil/gas wells under anisotropic in-situ stresses in the rock formation and uniform pressure within the casing. The present method treats the in-situ stresses in the formation as initial stresses since the in-situ stresses have already developed in the formation before placement of cement and casing into the well. It is demonstrated that, via this treatment, the present method excludes additional displacements within the formation predicted by the existing method, and gives more reasonable stress results. An actual tight-oil well is analyzed using the present and existing analytical methods, as well as the finite element method. Good agreement between the analytical results and the finite element analysis (FEA) results is obtained, validating the present method. It is also evident that, compared with the present method, the existing method overestimates the compressive stress level within the casing and the cement. Finally, the effects of elastic properties of the formation, cement, and inner pressure of casing on stresses within the casing and cement are illustrated with a series of sensitivity analyses. 展开更多
关键词 near wellbore region stress evaluation anisotropic in-situ stress initialstress
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Modeling Indicator Systems for Evaluating Environmental Sustainable Development Based on Factor Analysis 被引量:1
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作者 WU Hao CHEN Xiaoling +3 位作者 HE Ying HE Xiaorong CAI Xiaobin XU Keya 《Wuhan University Journal of Natural Sciences》 CAS 2006年第4期997-1002,共6页
Indicator systems of environmental sustainable development in the Poyang Lake Basin are established from 51 elementary indexes by factor analysis, which is composed of four steps such as the factor model, the paramete... Indicator systems of environmental sustainable development in the Poyang Lake Basin are established from 51 elementary indexes by factor analysis, which is composed of four steps such as the factor model, the parameter estimation, the factor rotation and the factor score. Under the condition that the cumulative proportion is greater than 85%, 5 explicit factors of environmental sustainable development as well as its factor score by region are carried out. The result indicates some impact factors to the basin environmental in descending sort order are volume of water, volume of waste gas discharge,volume of solid wasters.the degree to comprehensive utilization of waste gas, waste water and solid wastes, the emission volume of waste gas, waste water and solid wastes. It is helpful and important to provide decision support for constituting sustainable development strategies and evaluate the sustainable development status of each city. 展开更多
关键词 factor analysis the Poyang Lake Basin environment evaluation sustainable development indicator systems
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Designing and evaluating assessment and learning in adaptive learning systems 被引量:1
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作者 XI XIAOMING 《语言测试与评价》 2022年第1期94-115,119,120,共24页
The recent emergence of adaptive language learning systems calls for conceptual work to guide the design of assessment and learning in an adaptive environment.Although adaptive learning might have been touted as a uni... The recent emergence of adaptive language learning systems calls for conceptual work to guide the design of assessment and learning in an adaptive environment.Although adaptive learning might have been touted as a universal cure for learning problems,many adaptive language learning systems fall short of educators’expectations,partly due to a lack of standards and best practices in this area.To fill this gap,this paper proposes some major considerations in designing a high-quality assessment and learning experience in adaptive learning and ways to evaluate an adaptive learning system.The architecture of adaptive learning is decomposed,with a chain of inferences supporting the overall efficacy of an adaptive learning system presented,including user property representation,user property estimation,content representation,user interaction representation,and user interaction impact.A detailed analysis of key validity issues is provided for each inference,which motivates the major considerations in designing and evaluating assessment and learning.The paper first provides an overview of different types of assessment used in adaptive learning and an analysis of the assessment approach,priorities,and design considerations of each to optimize its use in adaptive learning.Then it proposes a framework for evaluating different aspects of an adaptive learning system.Some special connections are made to models,techniques,designs,and technologies specific to language learning and assessment,bringing more relevance to adaptive language learning solutions.Through establishing some guidelines on key aspects to evaluate and how to evaluate them,the work intends to bring more rigor to the field of adaptive language learning systems. 展开更多
关键词 ASSESSMENT adaptive learning evaluation framework EFFICACY validity
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Evaluation of the submarine debris-flow hazard risks to planned subsea pipeline systems: a case study in the Qiongdongnan Basin, South China Sea 被引量:1
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作者 Mingquan Huang Xuesheng Qian +1 位作者 Jingping Xu Xuecheng Li 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第5期139-153,共15页
The ever-increasing deepwater oil and gas development in the Qiongdongnan Basin,South China Sea has initiated the need to evaluate submarine debris-flow hazard risks to seafloor infrastructures.This paper presents a c... The ever-increasing deepwater oil and gas development in the Qiongdongnan Basin,South China Sea has initiated the need to evaluate submarine debris-flow hazard risks to seafloor infrastructures.This paper presents a case study on evaluating the debris-flow hazard risks to the planned pipeline systems in this region.We used a numerical model to perform simulations to support this quantitative evaluation.First,one relict failure interpreted across the development site was simulated.The back-analysis modeling was used to validate the applicability of the rheological parameters.Then,this model was applied to forecast the runout behaviors of future debris flows originating from the unstable upslope regions considered to be the most critical to the pipeline systems surrounding the Manifolds A and B.The model results showed that the potential debris-flow hazard risks rely on the location of structures and the selection of rheological parameters.For the Manifold B and connected pipeline systems,because of their remote distances away from unstable canyon flanks,the potential debris flows impose few risks.However,the pipeline systems around the Manifold A are exposed to significant hazard risks from future debris flows with selected rheological parameters.These results are beneficial for the design of a more resilient pipeline route in consideration of future debris-flow hazard risks. 展开更多
关键词 submarine debris flow pipeline MANIFOLD hazard evaluation route optimization Qiongdongnan Basin
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Blockchain-Empowered Token-Based Access Control System with User Reputation Evaluation 被引量:1
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作者 Yuzheng Yang Zhe Tu +1 位作者 Ying Liu Huachun Zhou 《Computers, Materials & Continua》 SCIE EI 2023年第12期3163-3184,共22页
Currently,data security and privacy protection are becoming more and more important.Access control is a method of authorization for users through predefined policies.Token-based access control(TBAC)enhances the manage... Currently,data security and privacy protection are becoming more and more important.Access control is a method of authorization for users through predefined policies.Token-based access control(TBAC)enhances the manageability of authorization through the token.However,traditional access control policies lack the ability to dynamically adjust based on user access behavior.Incorporating user reputation evaluation into access control can provide valuable feedback to enhance system security and flexibility.As a result,this paper proposes a blockchain-empowered TBAC system and introduces a user reputation evaluation module to provide feedback on access control.The TBAC system divides the access control process into three stages:policy upload,token request,and resource request.The user reputation evaluation module evaluates the user’s token reputation and resource reputation for the token request and resource request stages of the TBAC system.The proposed system is implemented using the Hyperledger Fabric blockchain.The TBAC system is evaluated to prove that it has high processing performance.The user reputation evaluation model is proved to be more conservative and sensitive by comparative study with other methods.In addition,the security analysis shows that the TBAC system has a certain anti-attack ability and can maintain stable operation under the Distributed Denial of Service(DDoS)attack environment. 展开更多
关键词 Access control reputation evaluation feedback blockchain
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Expert system for evaluating the safety of pressure vessels
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作者 董志波 卢亚峰 +3 位作者 魏艳红 杨永福 马瑞 郭萍 《China Welding》 EI CAS 2009年第2期21-24,共4页
With more application of welding technology in important structures more attention was paid to the evaluation of the safety of welded structures, the life prediction and decision to repair the welded structures. Based... With more application of welding technology in important structures more attention was paid to the evaluation of the safety of welded structures, the life prediction and decision to repair the welded structures. Based on material fracture mechanism and Chinese standard of safety evaluations of pressure vessels, an expert system was developed to evaluate the safety of welded pressure vessels. The system can analyze the weld defects in a pressure vessel, convert different kinds of defects into equivalent cracks and obtain their equivalent sizes. Furthermore, the system can calculate the stress and strain in the positions of weld defects and make decision on whether the defects are tolerable or not according to the code. When it is tolerable, the system will calculate the safety margin. The fatigue life can be predicted if the defects undergo fatigue load too. Moreover, data bases are built for storing mechanical properties of material and evaluated results. 展开更多
关键词 pressure vessel safety evaluation weld defects expert system data base
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