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Combing the Entropy Weight Method with Fuzzy Mathematics for Assessing the Quality and Post-Ripening Mechanism of High-Temperature Daqu during Storage
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作者 YANG Junlin YANG Shaojuan +8 位作者 WU Cheng YIN Yanshun YOU Xiaolong ZHAO Wenyu ZHU Anran WANG Jia HU Feng HU Jianfeng WANG Diqiang 《食品科学》 北大核心 2025年第9期48-62,共15页
This study investigated the physicochemical properties,enzyme activities,volatile flavor components,microbial communities,and sensory evaluation of high-temperature Daqu(HTD)during the maturation process,and a standar... This study investigated the physicochemical properties,enzyme activities,volatile flavor components,microbial communities,and sensory evaluation of high-temperature Daqu(HTD)during the maturation process,and a standard system was established for comprehensive quality evaluation of HTD.There were obvious changes in the physicochemical properties,enzyme activities,and volatile flavor components at different storage periods,which affected the sensory evaluation of HTD to a certain extent.The results of high-throughput sequencing revealed significant microbial diversity,and showed that the bacterial community changed significantly more than did the fungal community.During the storage process,the dominant bacterial genera were Kroppenstedtia and Thermoascus.The correlation between dominant microorganisms and quality indicators highlighted their role in HTD quality.Lactococcus,Candida,Pichia,Paecilomyces,and protease activity played a crucial role in the formation of isovaleraldehyde.Acidic protease activity had the greatest impact on the microbial community.Moisture promoted isobutyric acid generation.Furthermore,the comprehensive quality evaluation standard system was established by the entropy weight method combined with multi-factor fuzzy mathematics.Consequently,this study provides innovative insights for comprehensive quality evaluation of HTD during storage and establishes a groundwork for scientific and rational storage of HTD and quality control of sauce-flavor Baijiu. 展开更多
关键词 microbial community high-temperature Daqu comprehensive quality evaluation entropy weight method maturation process
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Prediction Method of Polar Navigation Window Period Based on Risk Evaluation
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作者 JIANG Jia−qi SHI Gui−jie WANG De−yu 《船舶力学》 北大核心 2025年第6期986-999,共14页
With the increase of international trade activities and the gradual melting of the polar ice cap,the importance of the Arctic route for marine transportation has been emphasized.Prediction of the polar navigation wind... With the increase of international trade activities and the gradual melting of the polar ice cap,the importance of the Arctic route for marine transportation has been emphasized.Prediction of the polar navigation window period is crucial for navigating in the Arctic route,which is of great significance to the selection of the route and the optimization of navigation.This paper introduces the establishment of a risk index system,determination of risk index weight,establishment of a risk evaluation model,and prediction algorithm for the window period.In addition,data sources of both environmental factors and ship factors are introducted,and their shortcomings are analyzed,followed by introduction of various methods involved in window prediction and analysis of their advantages and disadvantages.The quantitative risk evaluation and window period algorithm can provide a reference for the research of polar navigation window period prediction. 展开更多
关键词 window period risk evaluation polar navigation risk index
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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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Construction mechanism of whitenization weight function and its application in grey clustering evaluation 被引量:7
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作者 XIE Naiming SU Bentao CHEN Nanlei 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第1期121-131,共11页
The clustering evaluation can be used to scientifically classify the objects to be evaluated according to the information aggregation of various evaluation rules. In grey weighted clustering evaluation, the index clus... The clustering evaluation can be used to scientifically classify the objects to be evaluated according to the information aggregation of various evaluation rules. In grey weighted clustering evaluation, the index clustering rule relies on the construction of the whitenization weight function, while the existing construction method of the linear function lacks the construction mechanism analysis and validity explanation. A normative construction principle is put forward by analyzing the construction mechanism of the function. Through proving the normative principle of the function,the basic modal function(BMF) is proposed and characterized by different function forms. Then, a new type of the whitenization weight function and its grey clustering evaluation model algorithm are given by studying the mechanism and nature of the construction of different forms of the function. Finally, the comparative study for self-innovation capability of defense science and technology industry(DSTI) is taken as an example. The results show that the different construction ways of the function have an effect on the clustering result. The proposed construction mechanism can better explain the index clustering rules and evaluation effectiveness,which will perfect the theoretical system of grey clustering evaluation and be applied to practice effectively. 展开更多
关键词 whitenization weight FUNCTION GREY system theORY GREY CLUSTERING evaluation.
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Self-determinate evaluation method based on condition of weights non-dictatorial rate 被引量:3
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作者 Zhang Danning Yi Pingtao Guo Yajun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第2期310-320,共11页
The condition of weightes non-dictatorship is extended and a comprehensive evaluae method emboding self-determinate which is combined with competitive view optimization principles is built. The basic process includes ... The condition of weightes non-dictatorship is extended and a comprehensive evaluae method emboding self-determinate which is combined with competitive view optimization principles is built. The basic process includes simulating the model of economic man's self-benefit bahaviors, taking the place of experts to evaluate, bringing in the model of minimizing the sum of included angles to integrate the information of multiple objects and put the objects in order finally. The method has the advangtages of less dependendence on the subjective information, plenty of information, fair process and simple caculating. Finally, an application example is given to illustrate the effectiveness of the proposed method. 展开更多
关键词 condition of weights non-dictatorial rate principle of competitive view optimization self-determinate evaluation comprehensive evaluation
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Fuzzy-AHP-Based Comprehensive Evaluation on Facility Management System of High-Rise Office Buildings 被引量:2
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作者 ZHANG Peihong,WANG Kan,WAN Huanhuan,MA Zhongjiao(School of Environment Engineering,Shenyang Jianzhu University,Shenyang,China,110168) 《沈阳建筑大学学报(自然科学版)》 CAS 北大核心 2011年第2期324-330,共7页
The present building facility management status in China resulted in many problems such as high energy consumption,failure of automation control,services failure and poor indoor air quality.Based on questionnaires and... The present building facility management status in China resulted in many problems such as high energy consumption,failure of automation control,services failure and poor indoor air quality.Based on questionnaires and interviews to professional engineers and building users,a comprehensive evaluation index system was established on facility management of high-rise office buildings.A Fuzzy AHP based upon hierarchy criteria system was established.A Fuzzy AHP Evaluation Model on Facility Management System was set up;α-cut analysis was introduced and incorporated with expert knowledge together,which made up the optimism index λ.The fuzzy optimum crisp weight of each criterion was resulted from data-mining.Case investigations were processed in high-rise office buildings in Shenyang.The results illustrated that indoor air quality,thermal comfort and life cycle cost were the most important indexes in the evaluation of Facility Management System of high rise office buildings.Residents in high-rise buildings in Shenyang pay less attention to maintenance management and environment protection.By comparison with the analysis result of Export Choice,Fuzzy AHP-based evaluation model could act as a scientific reference for the establishment of governmental standards in facility management area in building. 展开更多
关键词 building facility management evaluation index Fuzzy AHP indoor air quality thermal comfort
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Evaluation method of cracking resistance of lightweight aggregate concrete 被引量:8
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作者 季韬 张彬彬 +1 位作者 陈永波 庄一舟 《Journal of Central South University》 SCIE EI CAS 2014年第4期1607-1615,共9页
The cracking behavior of lightweight aggregate concrete(LWAC) was investigated by mechanical analysis, SEM and cracking-resistant test where a shrinkage-restrained ring with a clapboard was used. The relationship betw... The cracking behavior of lightweight aggregate concrete(LWAC) was investigated by mechanical analysis, SEM and cracking-resistant test where a shrinkage-restrained ring with a clapboard was used. The relationship between the ceramsite type and the cracking resistance of LWAC was built up and compared with that of normal-weight coarse aggregate concrete(NWAC). A new method was proposed to evaluate the cracking resistance of concrete, where the concepts of cracking coefficient ζt(t) and the evaluation index Acr(t) were proposed, and the development of micro-cracks and damage accumulation were recognized. For the concrete with an ascending cracking coefficient curve, the larger Acr(t) is, the lower cracking resistance of concrete is. For the concrete with a descending cracking coefficient curve, the larger Acr(t) is, the stronger the cracking resistance of concrete is. The evaluation results show that in the case of that all the three types of coarse aggregates in concrete are pre-soaked for 24 h, NWAC has the lowest cracking resistance, followed by the LWAC with lower water absorption capacity ceramsite and the LWAC with higher water absorption capacity ceramsite has the strongest cracking resistance. The proposed method has obvious advantages over the cracking age method, because it can evaluate the cracking behavior of concrete even if the concrete has not an observable crack. 展开更多
关键词 ceramsite type cracking resistance lightweight aggregate concrete evaluation index evaluation method
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Numerical simulation of drop weight impact sensitivity evaluation criteria for pressed PBXs 被引量:1
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作者 Hong-zheng Duan Yan-qing Wu +1 位作者 Kun Yang Feng-lei Huang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第1期76-90,共15页
A thorough understanding of drop-weight impacted responses for polymer-bonded explosives(PBXs)is significant to evaluate their impact sensitivity.The characteristics of the drop-weight impacted pressed PBXs including ... A thorough understanding of drop-weight impacted responses for polymer-bonded explosives(PBXs)is significant to evaluate their impact sensitivity.The characteristics of the drop-weight impacted pressed PBXs including deforming,fracturing,forming a local high-temperature region and igniting,were simulated using a coupled mechanical-thermo-chemical model integrating micro-defects evolution.A novel evaluation method for impact sensitivity is established using the relation between the input kinetic energy and the output energy due to deformation,crushing energy,local hot spot energy and ignition.The effects of impact velocity on sensitivity were analyzed and the critical local ignition impact velocity is determined as 4.0-4.5 m/s.The simulated results show that shear-crack friction heating is the dominant ignition mechanism.The region along the boundary of PBXs sample is the most hazardous regions where ignition first occur.The propagation of stress wave in PBXs causes shear-crack hotspot and bulk temperature exhibiting an approximate 45°direction evolution path,which is the main reason that dominated damage-ignition region transits from the boundary to the central of sample. 展开更多
关键词 Polymer-bonded explosives(PBXs) Drop weight impact Numerical simulation Sensitivity evaluation criterion Hotspot mechanism
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Evaluation of global navigation satellite system spoofing efficacy 被引量:4
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作者 WANG Yue SUN Fuping +2 位作者 HAO Jinming ZHANG Lundong WANG Xian 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2022年第6期1238-1257,共20页
The spoofing capability of Global Navigation Satellite System(GNSS)represents an important confrontational capability for navigation security,and the success of planned missions may depend on the effective evaluation ... The spoofing capability of Global Navigation Satellite System(GNSS)represents an important confrontational capability for navigation security,and the success of planned missions may depend on the effective evaluation of spoofing capability.However,current evaluation systems face challenges arising from the irrationality of previous weighting methods,inapplicability of the conventional multi-attribute decision-making method and uncertainty existing in evaluation.To solve these difficulties,considering the validity of the obtained results,an evaluation method based on the game aggregated weight model and a joint approach involving the grey relational analysis and technique for order preference by similarity to an ideal solution(GRA-TOPSIS)are firstly proposed to determine the optimal scheme.Static and dynamic evaluation results under different schemes are then obtained via a fuzzy comprehensive assessment and an improved dynamic game method,to prioritize the deceptive efficacy of the equipment accurately and make pointed improvement for its core performance.The use of judging indicators,including Spearman rank correlation coefficient and so on,combined with obtained evaluation results,demonstrates the superiority of the proposed method and the optimal scheme by the horizontal comparison of different methods and vertical comparison of evaluation results.Finally,the results of field measurements and simulation tests show that the proposed method can better overcome the difficulties of existing methods and realize the effective evaluation. 展开更多
关键词 Global Navigation Satellite system(GNSS)spoofing index system for spoofing strategy game aggregated weight model grey relational analysis and technique for order preference by similarity to an ideal solution(GRA-TOPSIS)method dynamic game method
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Establishment and application of performance evaluation model for collection and transportation system of municipal solid waste
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作者 彭绪亚 林晓东 +2 位作者 贾传兴 王渝昆 黄媛媛 《Journal of Central South University》 SCIE EI CAS 2009年第S1期351-356,共6页
On the basis of analyzing the typical waste collection and transportation mode,the evaluation index system for performance of the waste collection and transportation system was proposed with three grades,which related... On the basis of analyzing the typical waste collection and transportation mode,the evaluation index system for performance of the waste collection and transportation system was proposed with three grades,which related to six factors,such as economic evaluation,high efficient evaluation,environmental impact assessment,resource evaluation,evaluation of security and emergency,evaluation of management and society. With the performance evaluation theory,the performance evaluation model of waste collection and transportation system was constructed,which quantified the grading standard of index and determined the index weight in analytic hierarchy process (AHP). After evaluating the waste collection and transportation system of the main districts of Chongqing city,the results show that the it has an excellent performance evaluation grade with very high performance level of three indices involving evaluation of management and society,environmental impact assessment,evaluation of security and emergency and quite low performance level of two indices that include high efficient evaluation and economic evaluation. 展开更多
关键词 MUNICIPAL solid waste COLLECTION and transportation system performance evaluation index system ANALYTIC HIERARCHY process
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Improved method for the feature extraction of laser scanner using genetic clustering 被引量:6
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作者 Yu Jinxia Cai Zixing Duan Zhuohua 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第2期280-285,共6页
Feature extraction of range images provided by ranging sensor is a key issue of pattern recognition. To automatically extract the environmental feature sensed by a 2D ranging sensor laser scanner, an improved method b... Feature extraction of range images provided by ranging sensor is a key issue of pattern recognition. To automatically extract the environmental feature sensed by a 2D ranging sensor laser scanner, an improved method based on genetic clustering VGA-clustering is presented. By integrating the spatial neighbouring information of range data into fuzzy clustering algorithm, a weighted fuzzy clustering algorithm (WFCA) instead of standard clustering algorithm is introduced to realize feature extraction of laser scanner. Aimed at the unknown clustering number in advance, several validation index functions are used to estimate the validity of different clustering algorithms and one validation index is selected as the fitness function of genetic algorithm so as to determine the accurate clustering number automatically. At the same time, an improved genetic algorithm IVGA on the basis of VGA is proposed to solve the local optimum of clustering algorithm, which is implemented by increasing the population diversity and improving the genetic operators of elitist rule to enhance the local search capacity and to quicken the convergence speed. By the comparison with other algorithms, the effectiveness of the algorithm introduced is demonstrated. 展开更多
关键词 laser scanner feature extraction weighted fuzzy clustering validation index genetic algorithm.
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Influence of expanded polystyrene size on deformation characteristics of light weight soil 被引量:15
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作者 侯天顺 《Journal of Central South University》 SCIE EI CAS 2012年第11期3320-3328,共9页
Deformation characteristics of light weight soil with different EPS (expanded polystyrene) sizes were investigated by consolidation tests.The results show that the confined stress-strain relation curve is in S shape,w... Deformation characteristics of light weight soil with different EPS (expanded polystyrene) sizes were investigated by consolidation tests.The results show that the confined stress-strain relation curve is in S shape,which has a good homologous relation with e-p curve and e-lgp curve,and three types of curves reflect obvious structural characteristics of light weight soil.When cement mixed ratio and EPS volume ratio are the same for different specimens,structural strength decreases with the increase of EPS size,but compressibility indexes basically keep unchanged within the structural strength.The settlement of light weight soil can be divided into instantaneous settlement and primary consolidation settlement.It has no obvious rheology property,and 90% of total consolidation deformation can be finished in 1 min.Settlement-time relation of light weight soil can be predicted by the hyperbolic model.S-lgt curve of light weight soil is not in anti-S shape.It is proved that there is no secondary consolidation section,so consolidation coefficient cannot be obtained by time logarithm method.Structural strength and unit price decrease with the increase of EPS size,but the reducing rate of the structural strength is lower than that of the unit price,so the cost of mixed soil can be reduced by increasing the EPS size.The EPS beads with 3-5 mm in diameter are suggested to be used in the construction process,and the prescription of mixed soil can be optimized. 展开更多
关键词 light weight soil expanded polystyrene (EPS) size effect one-dimensional consolidation theory compressibility index structural strength consolidation test
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MF-CFI:A fused evaluation index for camouflage patterns based on human visual perception 被引量:3
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作者 Xin Yang Wei-dong Xu +1 位作者 Qi Jia Jun Liu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2021年第5期1602-1608,共7页
The evaluation index of camouflage patterns is important in the field of military application.It is the goal that researchers have always pursued to make the computable evaluation indicators more in line with the huma... The evaluation index of camouflage patterns is important in the field of military application.It is the goal that researchers have always pursued to make the computable evaluation indicators more in line with the human visual mechanism.In order to make the evaluation method more computationally intelligent,a Multi-Feature Camouflage Fused Index(MF-CFI)is proposed based on the comparison of grayscale,color and texture features between the target and the background.In order to verify the effectiveness of the proposed index,eye movement experiments are conducted to compare the proposed index with existing indexes including Universal Image Quality Index(UIQI),Camouflage Similarity Index(CSI)and Structural Similarity(SSIM).Twenty-four different simulated targets are designed in a grassland background,28 observers participate in the experiment and record the eye movement data during the observation process.The results show that the highest Pearson correlation coefficient is observed between MF-CFI and the eye movement data,both in the designed digital camouflage patterns and largespot camouflage patterns.Since MF-CFI is more in line with the detection law of camouflage targets in human visual perception,the proposed index can be used for the comparison and parameter optimization of camouflage design algorithms. 展开更多
关键词 Camouflage evaluation Visual perception Effect assessment Fused index Eye movement analysis
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耦合DWT-IFLOF的大坝监测数据异常检测算法 被引量:3
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作者 王译羚 丁勇 李登华 《中国农村水利水电》 北大核心 2024年第7期203-209,共7页
基于数据驱动的模型已广泛应用于大坝运行状态建模与短期变形预测等领域中,而监测数据中存在的异常值会削弱甚至破坏数据驱动模型的可信度和鲁棒性。针对上述问题,提出一种耦合DWT-IFLOF的大坝监测数据异常检测算法。首先,采用小波降噪... 基于数据驱动的模型已广泛应用于大坝运行状态建模与短期变形预测等领域中,而监测数据中存在的异常值会削弱甚至破坏数据驱动模型的可信度和鲁棒性。针对上述问题,提出一种耦合DWT-IFLOF的大坝监测数据异常检测算法。首先,采用小波降噪技术减少监测数据集中采集噪声对模型建模的负面干扰。其次设计一种耦合孤立森林(iForest)异常检测算法与归一化局部离群因子值(LOF_(nor))的全新监测数据异常度量化表达式。最后通过引入拉伊达准则,依据计算得到的异常分数,对异常值进行定性筛查。试验结果表明,相较于热门异常检测算法,在查全率层面提升18.32%以上;查准率提升20.14%以上;准确率提升0.71%以上。可针对大坝安全监测数据中的异常值进行有效检测。 展开更多
关键词 异常检测 孤立森林 局部离群因子 评价指标
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一类双圈图的加权Kirchhoff指标
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作者 李成敏 边红 +1 位作者 于海征 杨雪 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第6期1073-1081,共9页
[目的]探究当图G是一个具有n+2个顶点的顶点赋权双圈图,且其中两个圈只有一个公共顶点时,图G的加权Kirchhoff指标公式.[方法]通过比较系数法和枚举法,首先对双圈图G中任意两个顶点v_(i)和v_(j)的分布情况进行分类,然后讨论在S(G)-v_(i)-... [目的]探究当图G是一个具有n+2个顶点的顶点赋权双圈图,且其中两个圈只有一个公共顶点时,图G的加权Kirchhoff指标公式.[方法]通过比较系数法和枚举法,首先对双圈图G中任意两个顶点v_(i)和v_(j)的分布情况进行分类,然后讨论在S(G)-v_(i)-v_(j)中不被n-匹配M所饱和的e-顶点的分布情况.[结果]经过对顶点v_(i)和v_(j)不同的3种分布情形进行详细分类讨论,本文得出的双圈图的加权Kirchhoff指标公式在每种情形下都成立,且这一结果将Li,Li和Yan等关于单圈图的相应结果推广到了具有两个圈且仅有一个公共顶点的双圈图上.[结论]针对两个圈只有一个公共顶点的双圈图的加权Kirchhoff指标公式可通过计算获得,并可通过其对应的顶点-边赋权剖分图S(G)^(ω*)及其相应子图的匹配权和来表示. 展开更多
关键词 加权Kirchhoff指标 双圈图 剖分图 完美匹配
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变负载下柔性系统的改进THEI输入整形器振动抑制
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作者 付威威 陶友瑞 +4 位作者 韩旭 胡俊宇 张建宁 李珊瑚 裴文良 《振动与冲击》 EI CSCD 北大核心 2024年第18期113-120,共8页
针对高精度运动平台中柔性系统负载改变而导致的固有频率和阻尼比双参数共同变化下输入整形器不敏感性优化问题,提出一种改进双股峰EI(two-hump extra-insensitive,THEI)输入整形器的设计方法,实现在相同滞后时间的前提下改善THEI输入... 针对高精度运动平台中柔性系统负载改变而导致的固有频率和阻尼比双参数共同变化下输入整形器不敏感性优化问题,提出一种改进双股峰EI(two-hump extra-insensitive,THEI)输入整形器的设计方法,实现在相同滞后时间的前提下改善THEI输入整形器的不敏感性。该改进THEI整形器在正向设计传统THEI输入整形器的基础上,加入对双参数不敏感性的反向优化。首先,利用三维灵敏度曲线推导了用于量化THEI输入整形器双参数不敏感性的评价指标。其次,建立了以幅值调节因子为设计变量的优化脉冲约束下THEI输入整形器双参数不敏感性优化模型;基于蚁群优化(ant colony optimization,ACO)算法求解设计变量,并更新改进THEI输入整形器的脉冲幅值,实现不敏感性最优。最后,数值仿真和试验结果共同验证了所提方法的有效性。 展开更多
关键词 参数变化 残余振动抑制 输入整形 不敏感性评价指标 鲁棒优化
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基于模糊层次分析的致密气储层广义平面阻流带识别 被引量:1
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作者 赖枫鹏 李彬册 +1 位作者 任广磊 张伟 《中国海上油气》 北大核心 2025年第1期129-138,共10页
致密气储层具有物性条件差、非均质性强、含水饱和度高等特点,储层中存在流体渗流受限区域,使得气井产量和控制储量受到影响。一般意义上的阻流带强调的是沉积、成岩作用,以及砂体边界发育等静态地质因素对生产的影响,缺少气水两相渗流... 致密气储层具有物性条件差、非均质性强、含水饱和度高等特点,储层中存在流体渗流受限区域,使得气井产量和控制储量受到影响。一般意义上的阻流带强调的是沉积、成岩作用,以及砂体边界发育等静态地质因素对生产的影响,缺少气水两相渗流过程中不同因素产生的动态阻流表征。首先明确了致密气储层广义平面阻流带的内涵,提出了从生产特征、储层特征和两相共渗特征三个方面进行分析。基于模糊层次分析法,建立了广义平面阻流带层次结构模型和综合评价指标(GI),以鄂尔多斯盆地某致密气藏井区为例,计算了不同因素的影响权重值,得到GI数值,通过插值绘制了研究区广义平面阻流带发育图。进一步对比研究了高产、中产、低产三类井无量纲产气量和无量纲产量递减率与GI数值的关系,结果表明:无量纲产气量与GI值呈负相关关系,无量纲产量递减率与GI值呈正相关关系。利用广义平面阻流带发育图可以为后续气井工作制度的优化调整提供科学支撑。 展开更多
关键词 致密气 广义平面阻流带 评价指标 识别方法 模糊层次分析 权重计算
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人工智能风险体系与模块化评价指标构建实证研究 被引量:2
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作者 苏文成 洪舒悦 +2 位作者 卢章平 刘桂锋 潘颖 《情报杂志》 北大核心 2025年第1期136-145,154,共11页
[研究目的]在人工智能蓬勃发展的时代,开展人工智能风险体系构建及其对应的模块化评价指标研究,以全面反映AI发展所带来的潜在风险,为不同领域的研究者提供决策依据。[研究方法]首先,基于扎根理论和专家调查法,系统地抽取和设计模块化... [研究目的]在人工智能蓬勃发展的时代,开展人工智能风险体系构建及其对应的模块化评价指标研究,以全面反映AI发展所带来的潜在风险,为不同领域的研究者提供决策依据。[研究方法]首先,基于扎根理论和专家调查法,系统地抽取和设计模块化人工智能风险评价指标;其次,采用层次分析法,对各指标权重进行测算,形成量化后的得分表,并对风险等级进行划分;最后,借助问卷调查法和专家调查法,对该体系进行应用实证研究,以验证其科学性及可行性。[研究结果/结论]人工智能风险体系包含由9个一级指标和41个二级指标组成的模块化评价指标。该体系涵盖技术、伦理、法律和社会等多个维度。基于此体系可以针对某一人工智能事件或功能,使用主观评价的方法对每一个风险子项进行打分,并最终得出总分。模块化指标可以灵活拆分,以量化测度不同领域的AI风险,兼顾全维度与具象维度的AI风险测度问题。 展开更多
关键词 人工智能 风险体系 风险评估 模块化评价指标 扎根理论 层次分析法
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基于组合主客观赋权法的茄衣质量评价 被引量:1
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作者 张友杰 薛野 +4 位作者 王以慧 徐继磊 仇京范 时向东 刘鹏飞 《河南农业科学》 北大核心 2025年第5期159-171,共13页
为了构建1个雪茄茄衣质量的综合评价方法,以国内外40份茄衣样品为研究对象,以茄衣外观质量、物理特性、化学成分和感官质量为评价指标,采用组合客观赋权法(CRITIC权重法、变异系数法、标准差法)与主观赋权法(层次分析法)相结合的方法,... 为了构建1个雪茄茄衣质量的综合评价方法,以国内外40份茄衣样品为研究对象,以茄衣外观质量、物理特性、化学成分和感官质量为评价指标,采用组合客观赋权法(CRITIC权重法、变异系数法、标准差法)与主观赋权法(层次分析法)相结合的方法,对雪茄茄衣质量进行评价。结果表明,主观赋权法中,外观质量权重为47.56%,物理特性权重为20.31%,化学成分权重为10.75%,感官质量权重为21.38%。组合客观赋权法与3种单一客观赋权法之间的一致性和相容性较好,且处理过程更为简单。组合主客观赋权法权重较大的指标为平衡含水率(4.89%)、拉力(4.54%),权重较小的指标为钾含量(0.53%)、还原糖/总糖(0.58%)。茄衣样品综合得分中,得分最高的为来自多米尼加的Primero E1(MSumatra)样品(0.79),得分最低的为来自印度尼西亚的HH1/MM1和来自巴西的WRB/CA/PFS-S样品(均为0.67);多米尼加产地茄衣综合得分最高(0.75),中国福建省产地最低(0.70)。 展开更多
关键词 茄衣 质量评价 权重 客观赋权法 主观赋权法
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基于分摊系数和加权综合指数法的DRG医师绩效评价及实证研究 被引量:1
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作者 杨业春 黄小红 +1 位作者 林圻 贺嘉嘉 《中国医院管理》 北大核心 2025年第1期78-82,共5页
目的 构建疾病诊断相关分组(DRG)医师绩效评价指标体系并开展实证研究。方法 运用“费用比例”构建“分摊系数”,明确“同一患者多个医师”的绩效权重分配方法;采用德尔菲法明确评价指标权重并运用加权综合指数法构建DRG医师绩效评价指... 目的 构建疾病诊断相关分组(DRG)医师绩效评价指标体系并开展实证研究。方法 运用“费用比例”构建“分摊系数”,明确“同一患者多个医师”的绩效权重分配方法;采用德尔菲法明确评价指标权重并运用加权综合指数法构建DRG医师绩效评价指标体系;基于医院数据开展医师绩效评价实证研究。结果 经绩效分摊和加权综合后,DRG基础评价指标及绩效评价指数均呈现0~100分的近似正态分布;基于DRG绩效评价指数可开展医师绩效的综合评价及优劣势分析;同一医师的评价结果采用绩效分摊较传统方法更为准确,尤其对转科患者较多的医师影响更为明显。结论 采用“分摊系数”进行“一患多医”的绩效权重分摊及评价指标加权的绩效综合评价指标体系的结果更为客观、准确,基于分摊系数和加权综合指数法的DRG医师绩效评价指标体系为医院的绩效分配和精细化管理提供了一种科学可行的方法。 展开更多
关键词 疾病诊断相关分组 医师 绩效 分摊系数 加权综合指数法
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