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Hierarchical hybrid testability modeling and evaluation method based on information fusion 被引量:4
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作者 Xishan Zhang Kaoli Huang +1 位作者 Pengcheng Yan Guangyao Lian 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第3期523-532,共10页
In order to meet the demand of testability analysis and evaluation for complex equipment under a small sample test in the equipment life cycle, the hierarchical hybrid testability model- ing and evaluation method (HH... In order to meet the demand of testability analysis and evaluation for complex equipment under a small sample test in the equipment life cycle, the hierarchical hybrid testability model- ing and evaluation method (HHTME), which combines the testabi- lity structure model (TSM) with the testability Bayesian networks model (TBNM), is presented. Firstly, the testability network topo- logy of complex equipment is built by using the hierarchical hybrid testability modeling method. Secondly, the prior conditional prob- ability distribution between network nodes is determined through expert experience. Then the Bayesian method is used to update the conditional probability distribution, according to history test information, virtual simulation information and similar product in- formation. Finally, the learned hierarchical hybrid testability model (HHTM) is used to estimate the testability of equipment. Compared with the results of other modeling methods, the relative deviation of the HHTM is only 0.52%, and the evaluation result is the most accu rate. 展开更多
关键词 small sample complex equipment hierarchical hybrid information fusion testability modeling and evaluation.
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Ballistic response mechanism and resistance-driven evaluation method of UHMWPE composite
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作者 Yemao He Johnny Qing Zhou +3 位作者 Yanan Jiao Hongshuai Lei Zeang Zhao Daining Fang 《Defence Technology(防务技术)》 2025年第2期1-16,共16页
The use of ultra-high molecular weight polyethylene(UHMWPE)composite in the design of lightweight protective equipment,has gained a lot of interest.However,there is an urgent need to understand the ballistic response ... The use of ultra-high molecular weight polyethylene(UHMWPE)composite in the design of lightweight protective equipment,has gained a lot of interest.However,there is an urgent need to understand the ballistic response mechanism and theoretical prediction model of performance.This paper explores the ballistic response mechanism of UHMWPE composite through experimental and simulation analyses.Then,a resistance-driven modeling method was proposed to establish a theoretical model for predicting the bulletproof performance.The ballistic response mechanism of UHMWPE composite encompassed three fundamental modes:local response,structural response,and coupled response.The occurrence ratio of these fundamental response modes during impact was dependent on the projectile velocity and laminate thickness.The bulletproof performance of laminate under different response modes was assessed based on the penetration depth of the projectile,the bulging height on the rear face of the laminate,the thickness of remaining sub-laminate,and residual velocity of the projectile.The absolute deviations of bulletproof performance indicator between theoretical value and experimental value were well within 11.13%,demonstrating that the established evaluation model possessed high degree of prediction accuracy. 展开更多
关键词 UHMWPE composite Ballistic response mechanism Theoretical model Performance evaluation
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Brittleness evaluation of gas-bearing coal based on statistical damage constitution model and energy evolution mechanism
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作者 XUE Yi WANG Lin-chao +5 位作者 LIU Yong RANJITH P G CAO Zheng-zheng SHI Xu-yang GAO Feng KONG Hai-ling 《Journal of Central South University》 2025年第2期566-581,共16页
Accurate assessment of coal brittleness is crucial in the design of coal seam drilling and underground coal mining operations.This study proposes a method for evaluating the brittleness of gas-bearing coal based on a ... Accurate assessment of coal brittleness is crucial in the design of coal seam drilling and underground coal mining operations.This study proposes a method for evaluating the brittleness of gas-bearing coal based on a statistical damage constitutive model and energy evolution mechanisms.Initially,integrating the principle of effective stress and the Hoek-Brown criterion,a statistical damage constitutive model for gas-bearing coal is established and validated through triaxial compression tests under different gas pressures to verify its accuracy and applicability.Subsequently,employing energy evolution mechanism,two energy characteristic parameters(elastic energy proportion and dissipated energy proportion)are analyzed.Based on the damage stress thresholds,the damage evolution characteristics of gas bearing coal were explored.Finally,by integrating energy characteristic parameters with damage parameters,a novel brittleness index is proposed.The results demonstrate that the theoretical curves derived from the statistical damage constitutive model closely align with the test curves,accurately reflecting the stress−strain characteristics of gas-bearing coal and revealing the stress drop and softening characteristics of coal in the post-peak stage.The shape parameter and scale parameter represent the brittleness and macroscopic strength of the coal,respectively.As gas pressure increases from 1 to 5 MPa,the shape parameter and the scale parameter decrease by 22.18%and 60.45%,respectively,indicating a reduction in both brittleness and strength of the coal.Parameters such as maximum damage rate and peak elastic energy storage limit positively correlate with coal brittleness.The brittleness index effectively captures the brittleness characteristics and reveals a decrease in brittleness and an increase in sensitivity to plastic deformation under higher gas pressure conditions. 展开更多
关键词 gas pressure statistical damage constitutive model energy evolution mechanism brittleness evaluation gas bearing coal
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Optimizing reliability, maintainability and testability parameters of equipment based on GSPN 被引量:3
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作者 Tingpeng Li Yue Li +1 位作者 Yanling Qian Yongcheng Xu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第3期633-643,共11页
Reliability, maintainability and testability (RMT) are important properties of equipment, since they have important influ- ence on operational availability and life cycle costs (LCC). There- fore, weighting and op... Reliability, maintainability and testability (RMT) are important properties of equipment, since they have important influ- ence on operational availability and life cycle costs (LCC). There- fore, weighting and optimizing the three properties are of great significance. A new approach for optimization of RMT parameters is proposed. First of all, the model for the equipment operation pro- cess is established based on the generalized stochastic Petri nets (GSPN) theory. Then, by solving the GSPN model, the quantitative relationship between operational availability and RMT parameters is obtained. Afterwards, taking history data of similar equipment and operation process into consideration, a cost model of design, manufacture and maintenance is developed. Based on operational availability, the cost model and parameters ranges, an optimization model of RMT parameters is built. Finally, the effectiveness and practicability of this approach are validated through an example. 展开更多
关键词 RELIABILITY MAINTAINABILITY testability optimization cost model operational availability.
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Catastrophe theory-based risk evaluation model for water and mud inrush and its application in karst tunnels 被引量:23
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作者 ZHU Jian-qun LI Tian-zheng 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第5期1587-1598,共12页
This paper presents a risk evaluation model of water and mud inrush for tunnel excavation in karst areas.The factors affecting the probabilities of water and mud inrush in karst tunnels are investigated to define the ... This paper presents a risk evaluation model of water and mud inrush for tunnel excavation in karst areas.The factors affecting the probabilities of water and mud inrush in karst tunnels are investigated to define the dangerousness of this geological disaster.The losses that are caused by water and mud inrush are taken into consideration to account for its harmfulness.Then a risk evaluation model based on the dangerousness-harmfulness evaluation indicator system is constructed,which is more convincing in comparison with the traditional methods.The catastrophe theory is used to evaluate the risk level of water and mud inrush and it has great advantage in handling problems involving discontinuous catastrophe processes.To validate the proposed approach,the Qiyueshan tunnel of Yichang-Wanzhou Railway is taken as an example in which four target segments are evaluated using the risk evaluation model.Finally,the evaluation results are compared with the excavation data,which shows that the risk levels predicted by the proposed approach are in good agreements with that observed in engineering.In conclusion,the catastrophe theory-based risk evaluation model is an efficient and effective approach for water and mud inrush in karst tunnels. 展开更多
关键词 risk evaluation model water and mud inrush catastrophe theory karst area TUNNELING
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Entropy weight coefficient model and its application in evaluation of groundwater vulnerability of the Sanjiang Plain 被引量:4
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作者 LIU Rentao FU Qiang GAI Zhaomei 《Journal of Northeast Agricultural University(English Edition)》 CAS 2007年第4期368-373,共6页
The research of groundwater vulnerability is the basic work to protect the groundwater. For utilizing groundwater resource continuably, groundwater vulnerability evaluation is necessary. Useful reference to protect, e... The research of groundwater vulnerability is the basic work to protect the groundwater. For utilizing groundwater resource continuably, groundwater vulnerability evaluation is necessary. Useful reference to protect, exploit and utilize on groundwater resource are provided rationally. According to the real condition of Sanjiang Plain, the indexes system is established based on the traditional DRASTIC model. The new system includes the following seven indexes: Depth of Water, Net Recharge, Aquifer Media, Soil Media, Conductivity of the Aquifer, Land Utilizing Ratio and Populace Density. The related analysis appears that the system is rather reasonable. Because traditional methods, such as analytic hierarchy process and fuzzy mathematics theory, can't be avoided human interference in selection of weights, they could lead to an imprecise result. In order to evaluate the groundwater vulnerability reasonably, entropy weight coefficient method is applied for the first time, which provides a new way to groundwater vulnerability evaluation. The method is a model whose weights are insured by the calculation process, so the artificial disturb can be avoided. It has been used to evaluate the groundwater vulnerability in Sanjiang Plain. The satisfied result is acquired. Comparably, the same result is acquired by the other method named projection pursuit evaluation based on real-coded accelerating genetic algorithm. It shows that entropy weight coefficient method is applicable on groundwater vulnerability evaluation. The evaluation result can provide reference on the decision-making departments. 展开更多
关键词 groundwater vulnerability entropy weight coefficient model indexes system evaluation
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Real-time lane departure warning system based on principal component analysis of grayscale distribution and risk evaluation model 被引量:4
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作者 张伟伟 宋晓琳 张桂香 《Journal of Central South University》 SCIE EI CAS 2014年第4期1633-1642,共10页
A technology for unintended lane departure warning was proposed. As crucial information, lane boundaries were detected based on principal component analysis of grayscale distribution in search bars of given number and... A technology for unintended lane departure warning was proposed. As crucial information, lane boundaries were detected based on principal component analysis of grayscale distribution in search bars of given number and then each search bar was tracked using Kalman filter between frames. The lane detection performance was evaluated and demonstrated in ways of receiver operating characteristic, dice similarity coefficient and real-time performance. For lane departure detection, a lane departure risk evaluation model based on lasting time and frequency was effectively executed on the ARM-based platform. Experimental results indicate that the algorithm generates satisfactory lane detection results under different traffic and lighting conditions, and the proposed warning mechanism sends effective warning signals, avoiding most false warning. 展开更多
关键词 lane departure warning system lane detection lane tracking principal component analysis risk evaluation model ARM-based real-time system
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3D Modeling Quantitative Evaluation for the Underground Space Resources in Beijing City
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作者 Yi Tian,Jianping Chen,Limei Wang School of Land Resources and Technology,China University of Geosciences(Beijing),Beijing 100083,China. 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期283-284,共2页
Recently,underground space evaluation has become fundamental for a city’s long term sustainable development planning.This paper,based on the 3D-GIS tools,adopts"multi-factors comprehensive evaluation"models... Recently,underground space evaluation has become fundamental for a city’s long term sustainable development planning.This paper,based on the 3D-GIS tools,adopts"multi-factors comprehensive evaluation"models to establish a practicable underground space resources quantitative evaluation system.It sets up 展开更多
关键词 CITY UNDERGROUND SPACE RESOURCES QUANTITATIVE evaluation 3D modeling
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Multiple-Attribute and Multilevel Synthetic Evaluation Model and Its Application
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作者 Wang Jianqiang & Gao Yang School of Business, Central South University, Changsha 410083, P. R. China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2003年第4期95-98,105,共5页
On the basis of analyzing the flaws of present multiple-attribute and multilevel evaluation methods, concerning the problem of characteristics of the multiple-attribute and multilevel system s appraisal and the partic... On the basis of analyzing the flaws of present multiple-attribute and multilevel evaluation methods, concerning the problem of characteristics of the multiple-attribute and multilevel system s appraisal and the particular emphasis on the respective attributes in the evaluation process, as well as its relevance to the environment, an optimal attribute system is proposed, and the multiplicative analytic hierarchy process (MAHP) is used to obtain subjective weight coefficients and the objective weight coefficient evaluating method is given. The deviation between the index value of each level and the values of the same index of other levels are formulated, and an optimal model is gained, thus establishing the weight coefficients of the whole optimal attribute system. Furthermore, the detailed implementation procedure of this method is introduced. Besides, favorable results have been gained by applying the model to the practical problems of economic evaluation. 展开更多
关键词 synthetic evaluation MODEL multiple-attribute and multilevel evaluation.
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Index Design and Comprehensive Evaluation of Germplasm Resources of Fruits Based on Mathematical Model of AHP and FCE:Sterculia nobilis Smith as a Case
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作者 Li Wen-yan Wei You Zhou Jing 《Journal of Northeast Agricultural University(English Edition)》 CAS 2021年第2期35-44,共10页
The mathematical model of analytic hierarchy process(AHP)-fuzzy comprehensive evaluation(FCE)was applied to comprehensively evaluate the germplasm resources of Sterculia nobilis Smith,and the scientific nature and rel... The mathematical model of analytic hierarchy process(AHP)-fuzzy comprehensive evaluation(FCE)was applied to comprehensively evaluate the germplasm resources of Sterculia nobilis Smith,and the scientific nature and reliability of the mathematical model was verified by calculating index weights and comprehensive evaluation scores.In this paper,11 indicators were selected to construct a comprehensive evaluation system from four dimensions of yields,resistances,contents of main inclusions in seeds and tree shapes.AHP method was applied to calculate the index weight of each dimension,after passing the consistency test,FCE method was applied to comprehensively evaluate germplasm resources of S.nobilis Smith.The index weights of the yields,resistances,contents of major inclusions in seeds and tree shapes were 0.5518,0.2554,0.1279 and 0.0649,respectively.The yield had the greatest influence on the comprehensive evaluation of germplasm resources of S.nobilis Smith,which was in line with the actual production demand of S.nobilis Smith as a food crop.However,resistances and contents of major inclusions in seeds had limited influence on it,while tree shapes had the least influence on it.After fuzzy comprehensive evaluation,the final evaluation score was 88.00,the corresponding evaluation score was between 4 and 5,and the evaluation results ranged from slight good to good,which indicated that the evaluation weights corresponding to the four dimensions were more scientific and reasonable.In this study,the mathematical model of AHP-FCE was used to establish and evaluate the comprehensive evaluation system of the germplasm resources of S.nobilis Smith.According to the values of index weights and the evaluation results,it showed that the mathematical model was scientific and reliable,and it could provide a new reference method for the comprehensive evaluation of germplasm resources of other fruits. 展开更多
关键词 Sterculia nobilis Smith comprehensive evaluation AHP-FCE mathematical model germplasm resource
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Risk transmission evaluation for parallel construction of warships based on IFCM and the cloud model
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作者 GONG Jun HU Tao YAO Lu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2022年第6期1224-1237,共14页
To cope with multi-directional transmission coupling,spreading, amplification, and chain reaction of risks during multiproject parallel construction of warships, a risk transmission evaluation method is proposed, whic... To cope with multi-directional transmission coupling,spreading, amplification, and chain reaction of risks during multiproject parallel construction of warships, a risk transmission evaluation method is proposed, which integrates an intuitionistic cloud model with a fuzzy cognitive map. By virtue of expectancy Ex, entropy En, and hyper entropy He, the risk fuzziness and randomness of the knowledge of experts are organically combined to develop a method for converting bi-linguistic variable decision-making information into the quantitative information of the intuitionistic normal cloud(INC) model. Subsequently, the threshold function and weighted summation operation in the traditional fuzzy cognitive map is converted into the INC ordered weighted averaging operator to create the risk transmission model based on the intuitionistic fuzzy cognitive map(IFCM) and the algorithm for solving it. Subsequently, the risk influence sequencing method based on INC and the risk rating method based on nearness are proposed on the basis of Monte Carlo simulation in order to realize the mutual conversion of the qualitative and quantitative information in the risk evaluation results.Example analysis is presented to verify the effectiveness and practicality of the methods. 展开更多
关键词 risk evaluation multi-project parallel intuitionistic fuzzy cognitive map(IFCM) intuitionistic normal cloud(INC)model warship construction.
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Evaluation of Productive Plant Landscapes in Cold Regions Based on a Multiple Cropping Model
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作者 Wu Zhi-heng Zhang Jia-xin +2 位作者 Zhu Xuan-bo Pan Sheng-kai Yan Yong-qing 《Journal of Northeast Agricultural University(English Edition)》 2023年第4期43-52,共10页
Four varieties of each rapeseed and buckwheat were planted in different sowing periods to explore a variety of planting patterns.A theoretical foundation was provided for the innovative application of cold region prod... Four varieties of each rapeseed and buckwheat were planted in different sowing periods to explore a variety of planting patterns.A theoretical foundation was provided for the innovative application of cold region productive plant landscapes.The analytic hierarchy process was employed to develop a model for the evaluation of multiple cropping systems.A comprehensive evaluation was conducted to study 10 indicators in plant type,flower color,flowering period,flower volume,branch coverage,plot average yield,number of grains per plant,yield per plant,thousand-grain quality and ecological adaptability in four different varieties of each rapeseed and buckwheat.The results indicated that flower color,ecological adaptability,plot average yield and flower volume were the most important indicators for the value of productive plant landscapes in cold regions.Concerning the sowing period,the optimal combination of varieties and planting times were March 31 for Qingza No.5(rapeseed)and July 18 for Xinong T1211(buckwheat). 展开更多
关键词 multiple cropping model RAPESEED BUCKWHEAT analytic hierarchy process comprehensive evaluation
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基于DEA模型的医院学科科研绩效评价探析 被引量:3
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作者 耿华 杨林 周丽 《中国医院》 北大核心 2025年第3期55-59,共5页
目的:通过新视角探析医院学科科研绩效,为管理机构制定学科管理政策及完善学科管理体系提供参考。方法:以SD医院学科建设为例,构建投入-产出相关联的绩效评价指标体系。采用数据包络分析(DEA)模型对SD医院优势学科建设的绩效进行评价,... 目的:通过新视角探析医院学科科研绩效,为管理机构制定学科管理政策及完善学科管理体系提供参考。方法:以SD医院学科建设为例,构建投入-产出相关联的绩效评价指标体系。采用数据包络分析(DEA)模型对SD医院优势学科建设的绩效进行评价,重点关注学科资源配置和利用的有效性,并进行静态和动态相结合的实证分析。结果:学科DEA有效个数总体上呈增长趋势,表明科研投入产出水平较高,科研资源大体上能够得到合理配置。学科科研全要素生产率近3年处于增长趋势,促进了科技的创新和发展。然而,部分学科存在规模报酬不合理、技术水平低的问题,导致全要素生产率较低。结论:医院应加强制度建设,不断完善学科绩效评价机制;加强科研经费的内部控制,促进经费使用更加科学;鼓励多学科协同,搭建共享平台和交叉平台,构建标准作业程序;强化科研成果转化,发挥价值驱动的引导与激励作用,以支持学科建设的持续发展。 展开更多
关键词 DEA模型 绩效评价 学科建设 科研经费
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基于博弈论-改进云模型的新能源电力系统适应性评估 被引量:3
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作者 汤明润 李若旸 +3 位作者 程晓钰 代馨尹 于雪丰 杨淑霞 《电力系统保护与控制》 北大核心 2025年第7期40-51,共12页
发展新能源电力系统是实现双碳目标的要求,因此对一定状态下新能源电力系统适应性进行评估具有重要意义。首先,分析了新能源电力系统适应性的影响因素,基于新能源电力系统的特点,建立了适应性评价指标体系,包含电网结构、经济性和能源... 发展新能源电力系统是实现双碳目标的要求,因此对一定状态下新能源电力系统适应性进行评估具有重要意义。首先,分析了新能源电力系统适应性的影响因素,基于新能源电力系统的特点,建立了适应性评价指标体系,包含电网结构、经济性和能源结构等3个一级指标及15个二级指标。其次,基于博弈理论进行组合赋权,综合了熵权法、CRITIC法及变异系数法3种客观赋权法,得到最佳组合权重。然后,提出了改进云模型,以此克服指标本身的随机性,并通过组合权重对云模型进行改进,用以评价新能源电力系统的适应能力。最后,选取我国A地区配电网进行算例分析,验证了所提评估模型的准确性及有效性,为识别新能源电力系统的脆弱性、提升新能源电力系统的适应能力提供可靠的建议。 展开更多
关键词 新能源电力系统 适应性评估 博弈论思想 改进云模型 综合评价
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大模型驱动科技创新评价若干问题的思考 被引量:6
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作者 张洋 吴婷婷 侯剑华 《图书情报知识》 北大核心 2025年第1期70-77,88,共9页
[目的/意义]大科学时代背景下,大模型驱动的科技创新评价范式正在发生深刻的变革。厘清大模型驱动的科技创新评价若干问题,有助于提升评价的实用价值和战略指导意义,为科技进步和社会发展提供强有力的支持。[研究设计/方法]基于科技创... [目的/意义]大科学时代背景下,大模型驱动的科技创新评价范式正在发生深刻的变革。厘清大模型驱动的科技创新评价若干问题,有助于提升评价的实用价值和战略指导意义,为科技进步和社会发展提供强有力的支持。[研究设计/方法]基于科技创新评价演化历程和大模型驱动科技创新评价的主要特征,深度剖析大模型应用于科技创新评价的主要维度,在此基础上思考大模型驱动科技创新评价所面临的若干挑战和未来发展趋势。[结论/发现]大模型驱动的科技创新评价将成为新时期科技评价范式变革和进步的关键力量。大模型使得科技创新评价更加智能化、精细化和个性化,其与科学研究、技术开发、科技评价、科技管理等领域的融合发展将成为必然趋势。[创新/价值]剖析了大模型应用于科技创新评价的若干问题,为构建以智能化、精细化、系统化和个性化为核心,以可持续和负责任的评价为导向的科技创新评价体系提供参考和依据。 展开更多
关键词 科技创新评价 大模型 数智驱动
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职业教育数字化转型能力成熟度模型与评估方法 被引量:4
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作者 邱飞岳 张彭丽 +2 位作者 袁霄 黄江 郭海东 《远程教育杂志》 北大核心 2025年第1期75-84,共10页
教育数字化转型是推动全球教育革新和重塑竞争优势的重要方向。职业教育,作为经济社会发展的关键动力,正在主动求变、积极应变。为了科学有效地评估职业院校的数字化转型程度及能力,研究基于成熟度模型视角,提出了切实可行的评估方案。... 教育数字化转型是推动全球教育革新和重塑竞争优势的重要方向。职业教育,作为经济社会发展的关键动力,正在主动求变、积极应变。为了科学有效地评估职业院校的数字化转型程度及能力,研究基于成熟度模型视角,提出了切实可行的评估方案。具体而言,研究首先从院校个体、群体标杆、职教蓝图三个层面展开价值探索,系统剖析了成熟度模型的构成要素及教育数字化转型成熟度模型的共性特征;其次,结合我国职业教育数字化发展特色,构建了一个包含五个成熟度等级、四个能力要素、九个能力域和二十五个能力子域的职业教育数字化转型能力成熟度模型;最后,详细阐述了评估方法与实施流程。该模型旨在帮助职业院校评估自身数字化转型能力成熟度,识别发展瓶颈,进而采取针对性的措施提升数字化水平,以更好地适应现代职业教育高质量发展的需求。 展开更多
关键词 职业教育数字化 能力成熟度模型 成熟度等级 评估方法与流程
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融合SVM-RFE与层次分析-信息量模型的地质灾害易发性评价 被引量:1
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作者 李文杰 巨能攀 +2 位作者 王栋 陈浩 解明礼 《自然灾害学报》 北大核心 2025年第3期99-109,共11页
我国地质灾害频发,严重威胁人民群众的生命及财产安全,开展地质灾害易发性评价工作对地质灾害防治起着重要的作用。目前,针对地质灾害易发性评价,其评价因子的选取多为单一定性分析,主观性较强,缺乏科学性,同时因子之间的相互关系考虑... 我国地质灾害频发,严重威胁人民群众的生命及财产安全,开展地质灾害易发性评价工作对地质灾害防治起着重要的作用。目前,针对地质灾害易发性评价,其评价因子的选取多为单一定性分析,主观性较强,缺乏科学性,同时因子之间的相互关系考虑较少。文中以林芝市为例,选取高程、坡度、坡向等14个初始影响因子,通过基于支持向量机的递归特征消除(support vector machine-recursive feature elimination,SVM-RFE)算法对因子进行重要性排序及筛选,采用皮尔逊相关性分析考虑因子之间的相互关系,结合重要性排序消除相关性较高的因子,从而确定出了12组易发性评价因子,并基于层次分析-信息量模型开展林芝市地质灾害易发性评价,采用成功率曲线进行结果精度检验。结果表明:研究区内地质灾害极高易发区和高易发区主要集中在主道路及其附近,以及主要水系延伸地区;高易发区是研究区内所占面积最广的区域,面积为45 312.16 km^(2),占林芝市总面积的30.37%。根据评价结果精度检验得到曲线下面积(area under curve,AUC)值为0.846,表明本方法开展地质灾害易发性评价的准确率较高,可为林芝市地质灾害防治和经济建设提供科学依据。 展开更多
关键词 SVM-RFE 层次分析-信息量模型 地质灾害 评价因子 易发性评价
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跨学科主题学习成效测评模型的构建与应用:基于学生自我评估视角 被引量:1
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作者 吴鹏泽 胡晓玲 李冰 《中国电化教育》 北大核心 2025年第4期66-74,共9页
跨学科主题学习是培养中小学生核心素养、应对未来挑战的关键手段,在新课程改革中占据重要地位。构建科学、全面的跨学科主题学习成效测评体系是确保跨学科教育质量的关键。该研究基于柯氏模型,通过两轮专家咨询构建了测评框架,并基于... 跨学科主题学习是培养中小学生核心素养、应对未来挑战的关键手段,在新课程改革中占据重要地位。构建科学、全面的跨学科主题学习成效测评体系是确保跨学科教育质量的关键。该研究基于柯氏模型,通过两轮专家咨询构建了测评框架,并基于学生自我评估的测评量表进行验证,形成了包含满意度、素养、投入度和结果的中小学跨学科主题学习成效测评模型。通过对全国31个省市自治区参与过跨学科主题学习的11062名中小学生进行调查,发现跨学科主题学习成效整体良好,但学段、地区(城区与非城区)及参与频次不同的学生在成效上存在显著差异。最后,研究从重视学生跨学科素养培育、关注跨学科教育均衡发展两方面提出了建议。 展开更多
关键词 跨学科主题学习 测评模型 实施成效 柯氏模型
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改进sinobrand模型的农产品区域品牌价值评估 被引量:1
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作者 夏雪琦 李春波 《绿色科技》 2024年第13期251-256,共6页
农产品品牌化是建设农业强国的关键步骤,对农产品区域品牌价值进行评估对农产品品牌化具有重要的推动作用。梳理了农产品区域品牌评估方法的研究现状,选用sinobrand模型对农产品区域品牌价值进行评估,并对品牌优势值的测算作出改进,将... 农产品品牌化是建设农业强国的关键步骤,对农产品区域品牌价值进行评估对农产品品牌化具有重要的推动作用。梳理了农产品区域品牌评估方法的研究现状,选用sinobrand模型对农产品区域品牌价值进行评估,并对品牌优势值的测算作出改进,将消费者偏好引入品牌强度评价指标后结合爬虫以及文本情感分析技术进行衡量,得到汉源花椒品牌价值为149.55亿元,验证了改进sinobrand模型的适用性,针对汉源花椒品牌价值提升提出了注重品牌保护、宣传汉源花椒品牌故事、与其他行业品牌合作等建议,以期提供参考。 展开更多
关键词 sinobrand模型 品牌价值评估 农产品区域品牌 汉源花椒
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准噶尔盆地东部隆起煤层气成藏条件与选区评价 被引量:4
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作者 余琪祥 田蜜 +5 位作者 罗宇 杨帆 陈彦鄂 王烽 高玉巧 郭涛 《石油实验地质》 北大核心 2025年第1期117-129,共13页
准噶尔盆地东部隆起具有较好的煤层气勘探前景,开展煤层气选区与评价,将为该区煤层气勘探提供科学依据和勘探方向。利用探井钻测录试资料、岩心分析测试数据和地震资料,开展井—震标定和地震剖面解释,编制了侏罗系八道湾组和西山窑组煤... 准噶尔盆地东部隆起具有较好的煤层气勘探前景,开展煤层气选区与评价,将为该区煤层气勘探提供科学依据和勘探方向。利用探井钻测录试资料、岩心分析测试数据和地震资料,开展井—震标定和地震剖面解释,编制了侏罗系八道湾组和西山窑组煤层连井剖面和煤层厚度分布图;分析了研究区内煤层气气源、煤岩基本特征、储层物性、含气性和保存条件等成藏主控因素。研究表明:(1)西山窑组煤层在沙奇凸起以北五彩湾凹陷—梧桐窝子凹陷连片分布,在沙奇凸起以南则主要分布于吉木萨尔凹陷—吉南凹陷;八道湾组煤层分割性较强,主要分布于凹陷内部分地区。(2)区内存在自源型煤层生物成因气、低成熟热成因气和深部外源型高成熟气条件。(3)煤岩有机组分以惰质组为主,镜质组次之,壳质组少量;煤岩镜质组反射率低(0.39%~0.47%),为低煤级煤;煤岩瓦斯气体成分主要为N_(2)、CO_(2)和CH_(4),其中N_(2)占绝对优势;煤岩总含气量中可燃气体(CH_(4))含量低。(4)煤层气富集成藏模式分为山前断陷富集成藏模式、深部凹陷富集成藏模式和开放斜坡逸散模式。(5)建立了煤层气评价参数和划分标准,五彩湾凹陷、梧桐窝子凹陷、吉木萨尔凹陷和吉南凹陷为煤层气勘探有利区;沙帐断褶带和石钱滩凹陷为较有利区;石树沟凹陷和古城凹陷为不利区。 展开更多
关键词 选区评价 成藏主控因素 富集成藏模式 煤层气 东部隆起 准噶尔盆地
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