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A Decision-Making Framework Model of Cutting Fluid Selection for Green Manufacturing and the Case Study 被引量:5
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作者 TAN Xian-chun 1, LIU Fei 1, CAO Hua-jun 1, ZHANG Hua 2 (1. The Institute of Manufacturing Engineering, Chongqing University, Chongqing 400044, China 2. School of Manufacturing & Automation, Wuhan University of Science & Technol ogy, Wuhan 430081, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期136-137,共2页
Pursuing the green manufacturing (GM) of products i s very beneficial in the alleviation of environment burdens. In order to reap such benefits, green manufacturing is involved in every aspect of manufacturing proc es... Pursuing the green manufacturing (GM) of products i s very beneficial in the alleviation of environment burdens. In order to reap such benefits, green manufacturing is involved in every aspect of manufacturing proc esses. During the machining process, cutting fluid is one of the main roots of e nvironmental pollution. And how to make an optimal selection for cutting fluid f or GM is an important path to reduce the environmental pollution. The objective factors of decision-making problems in the traditional selection of cutting flu id are usually two: quality and cost. But from the viewpoint of GM, environmenta l impact (E) should be considered together. In this paper, a multi-object d ecision-making model of cutting fluid selection for GM is put forward, in which the objects of Quality (Q), Cost(C) and Environmental impact (E) are considered together. In this model, E means to minimize the environmental impact, Q means to maximize the quality and C means to minimize the cost. Each objective is anal yzed in detail too. A case study on a decision-making problem of cutting fluid selection in a gear hobbing process is analyzed, and the result shows the model is practical. 展开更多
关键词 green manufacturing cutting fluid decision-mak ing model environmental impact
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Ranking environmental projects model based on multicriteria decision-making and the weight sensitivity analysis 被引量:5
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作者 Jiang Yan Tian Dagang Pan Yue 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第3期534-539,共6页
With the fast growth of Chinese economic, more and more capital will be invested in environmental projects. How to select the environmental investment projects (alternatives) for obtaining the best environmental qua... With the fast growth of Chinese economic, more and more capital will be invested in environmental projects. How to select the environmental investment projects (alternatives) for obtaining the best environmental quality and economic benefits is an important problem for the decision makers. The purpose of this paper is to develop a decision-making model to rank a finite number of alternatives with several and sometimes conflicting criteria. A model for ranking the projects of municipal sewage treatment plants is proposed by using exports' information and the data of the real projects. And, the ranking result is given based on the PROMETHEE method. Furthermore, by means of the concept of the weight stability intervals (WSI), the sensitivity of the ranking results to the size of criteria values and the change of weights value of criteria are discussed. The result shows that some criteria, such as “proportion of benefit to project cost”, will influence the ranking result of alternatives very strong while others not. The influence are not only from the value of criterion but also from the changing the weight of criterion. So, some criteria such as “proportion of benefit to project cost” are key critera for ranking the projects. Decision makers must be cautious to them. 展开更多
关键词 multicriteria decision-making ranking environmental projects model PROMETHEE method sensitivity analysis weight stability intervals.
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Consensus model of social network group decision-making based on trust relationship among experts and expert reliability 被引量:4
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作者 WANG Ya CAI Mei JIAN Xinglian 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第6期1576-1588,共13页
Due to people’s increasing dependence on social networks,it is essential to develop a consensus model considering not only their own factors but also the interaction between people.Both external trust relationship am... Due to people’s increasing dependence on social networks,it is essential to develop a consensus model considering not only their own factors but also the interaction between people.Both external trust relationship among experts and the internal reliability of experts are important factors in decision-making.This paper focuses on improving the scientificity and effectiveness of decision-making and presents a consensus model combining trust relationship among experts and expert reliability in social network group decision-making(SN-GDM).A concept named matching degree is proposed to measure expert reliability.Meanwhile,linguistic information is applied to manage the imprecise and vague information.Matching degree is expressed by a 2-tuple linguistic model,and experts’preferences are measured by a probabilistic linguistic term set(PLTS).Subsequently,a hybrid weight is explored to weigh experts’importance in a group.Then a consensus measure is introduced and a feedback mechanism is developed to produce some personalized recommendations with higher group consensus.Finally,a comparative example is provided to prove the scientificity and effectiveness of the proposed consensus model. 展开更多
关键词 social network group decision-making(SN-GDM) trust relationship expert reliability consensus model probabilistic linguistic term set(PLTS).
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Risk-based water quality decision-making under small data using Bayesian network 被引量:3
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作者 张庆庆 许月萍 +1 位作者 田烨 张徐杰 《Journal of Central South University》 SCIE EI CAS 2012年第11期3215-3224,共10页
A knowledge-based network for Section Yidong Bridge,Dongyang River,one tributary of Qiantang River,Zhejiang Province,China,is established in order to model water quality in areas under small data.Then,based on normal ... A knowledge-based network for Section Yidong Bridge,Dongyang River,one tributary of Qiantang River,Zhejiang Province,China,is established in order to model water quality in areas under small data.Then,based on normal transformation of variables with routine monitoring data and normal assumption of variables without routine monitoring data,a conditional linear Gaussian Bayesian network is constructed.A "two-constraint selection" procedure is proposed to estimate potential parameter values under small data.Among all potential parameter values,the ones that are most probable are selected as the "representatives".Finally,the risks of pollutant concentration exceeding national water quality standards are calculated and pollution reduction decisions for decision-making reference are proposed.The final results show that conditional linear Gaussian Bayesian network and "two-constraint selection" procedure are very useful in evaluating risks when there is limited data and can help managers to make sound decisions under small data. 展开更多
关键词 water quality risk pollution reduction decisions Bayesian network conditional linear Gaussian model small data
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Method for Risky Multiobjective Group Decision-Making and Its Application
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作者 Yu Yibin & Wang Bende Department of Civil and Hydraulic Engineering, Dalian University of Technology, Dalian 116024, P. R. China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2003年第4期7-12,共6页
The multiobjective group decision-making problem under risk is common in reality. This paper focuses on the study about risky multiobjective group decision-making problem where the index value is not certain. We give ... The multiobjective group decision-making problem under risk is common in reality. This paper focuses on the study about risky multiobjective group decision-making problem where the index value is not certain. We give indexes classifying method and index normalizing formula of this type problem. By building objective function that minimizes general weighted distance from every alternative to the relatively best and worst alternative, the optimal membership degree of every decision-maker to every alternative can be obtained, and by building another objective function that minimizes general weighted distance from the optimal membership degree of every decision-maker to every alternative to the group optimal alternative and the group inferior alternative, the optimal membership degree of every decision-maker to every alternative can be obtained, which are both based on probability theory and fuzzy theory. Aftermost a model is established which collects group preferences. This method provides a new idea and approach for solving multiobjective decision-making problem among uncertain system, which is applicable for practical problem. Finally a case study shows a satisfactory result. 展开更多
关键词 multiobjective decision-making risk PROBABILITY relative optimal membership degree weights.
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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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Model calibration concerning risk coefficients of driving safety field model 被引量:6
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作者 LI Yang WANG Jian-qiang WU Jian 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第6期1494-1502,共9页
Driving safety field(DSF) model has been proposed to represent comprehensive driving risk formed by interactions of driver-vehicle-road in mixed traffic environment. In this work, we establish an optimization model ba... Driving safety field(DSF) model has been proposed to represent comprehensive driving risk formed by interactions of driver-vehicle-road in mixed traffic environment. In this work, we establish an optimization model based on grey relation degree analysis to calibrate risk coefficients of DSF model. To solve the optimum solution, a genetic algorithm is employed. Finally, the DSF model is verified through a real-world driving experiment. Results show that the DSF model is consistent with driver's hazard perception and more sensitive than TTC. Moreover, the proposed DSF model offers a novel way for criticality assessment and decision-making of advanced driver assistance systems and intelligent connected vehicles. 展开更多
关键词 intelligent CONNECTED vehicles advanced DRIVER ASSISTANCE systems (ADAS) driving risk assessment driving safety field (DSF) model parameter calibration GREY relation DEGREE
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Research on the self-defence electronic jamming decision-making based on the discrete dynamic Bayesian network 被引量:6
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作者 Tang Zheng Gao Xiaoguang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第4期702-708,共7页
The manner and conditions of running the decision-making system with self-defense electronic jamming are given. After proposing the scenario of applying discrete dynamic Bayesian network to the decision making with se... The manner and conditions of running the decision-making system with self-defense electronic jamming are given. After proposing the scenario of applying discrete dynamic Bayesian network to the decision making with self-defense electronic jamming, a decision-making model with self-defense electronic jamming based on the discrete dynamic Bayesian network is established. Then jamming decision inferences by the aid of the algorithm of discrete dynamic Bayesian network are carried on. The simulating result shows that this method is able to synthesize different targets which are not predominant. In this way, various features at the same time, as well as the same feature appearing at different time complement mutually; in addition, the accuracy and reliability of electronic jamming decision making are enhanced significantly. 展开更多
关键词 self-defense electronic jamming discrete dynamic Bayesian network decision-making model
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Risk assessment model of tunnel water inrush based on improved attribute mathematical theory 被引量:12
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作者 YANG Xiao-li ZHANG Sheng 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第2期379-391,共13页
Tunnel water inrush is one of the common geological disasters in the underground engineering construction.In order to effectively evaluate and control the occurrence of water inrush,the risk assessment model of tunnel... Tunnel water inrush is one of the common geological disasters in the underground engineering construction.In order to effectively evaluate and control the occurrence of water inrush,the risk assessment model of tunnel water inrush was proposed based on improved attribute mathematical theory.The trigonometric functions were adopted to optimize the attribute mathematical theory,avoiding the influence of mutation points and linear variation zones in traditional linear measurement functions on the accuracy of the model.Based on comprehensive analysis of various factors,five parameters were selected as the evaluation indicators for the model,including tunnel head pressure,permeability coefficient of surrounding rock,crushing degree of surrounding rock,relative angle of joint plane and tunnel section size,under the principle of dimension rationality,independence,directness and quantification.The indicator classifications were determined.The links among measured data were analyzed in detail,and the objective weight of each indicator was determined by using similar weight method.Thereby the tunnel water inrush risk assessment model is established and applied in four target segments of two different tunnels in engineering.The evaluation results and the actual excavation data agree well,which indicates that the model is of high credibility and feasibility. 展开更多
关键词 tunnel water inrush risk assessment model attribute mathematical theory nonlinear measurement function similar weight method
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Risk Assessment of Coal Mine Water Hazard Based on Three-Dimensional Model of Geology and Underground Space 被引量:1
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作者 Kai Zhang~1,Ming Huang~1,Bin Tang~2,Fan Cui~1 1.Laboratory of Coal Resources and Mine Safety,China University of Mining and Technology,Beijing 100083,China. 2.China Water Investment Co.Ltd,Beijing 100053,China 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期279-279,共1页
Mine safety have top-five disasters,which including the water,gas,fire,dust and geological dynamic disaster.The coal mine water disaster is one of the important factors which restricted the development of China’s coa... Mine safety have top-five disasters,which including the water,gas,fire,dust and geological dynamic disaster.The coal mine water disaster is one of the important factors which restricted the development of China’s coal production.It is showed by statistics that 60%of mine accidents are affected by groundwater,which not only result in the production losses,casualties and a variety of 展开更多
关键词 DISASTER risk assessment THREE-DIMENSIONAL model of GEOLOGY and UNDERGROUND space emergency RESCUE
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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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Statistical inference for dependence competing risks model under middle censoring
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作者 WANG Yan SHI Yimin WU Min 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第1期209-222,共14页
Middle censoring is an important censoring scheme,in which the actual failure data of an observation becomes unobservable if it falls into a random interval. This paper considers the statistical analysis of the depend... Middle censoring is an important censoring scheme,in which the actual failure data of an observation becomes unobservable if it falls into a random interval. This paper considers the statistical analysis of the dependent competing risks model by using the Marshall-Olkin bivariate Weibull(MOBW) distribution.The maximum likelihood estimations(MLEs), midpoint approximation(MPA) estimations and approximate confidence intervals(ACIs) of the unknown parameters are obtained. In addition, the Bayes approach is also considered based on the Gamma-Dirichlet prior of the scale parameters, with the given shape parameter.The acceptance-rejection sampling method is used to obtain the Bayes estimations and construct credible intervals(CIs). Finally,two numerical examples are used to show the performance of the proposed methods. 展开更多
关键词 MIDDLE CENSORING DEPENDENT competing riskS model Marshall-Olkin BIVARIATE Weibull (MOBW) distribution acceptancerejection sampling.
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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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大语言模型安全性:分类、评估、归因、缓解、展望 被引量:4
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作者 黄河燕 李思霖 +7 位作者 兰天伟 邱昱力 柳泽明 姚嘉树 曾理 单赢宇 施晓明 郭宇航 《智能系统学报》 北大核心 2025年第1期2-32,共31页
大语言模型能够在多个领域及任务上给出与人类水平相当的解答,并且在未经训练的领域和任务上展现了丰富的涌现能力。然而,目前基于大语言模型的人工智能系统存在许多安全性隐患,例如大语言模型系统容易受到难以被察觉的攻击,模型生成的... 大语言模型能够在多个领域及任务上给出与人类水平相当的解答,并且在未经训练的领域和任务上展现了丰富的涌现能力。然而,目前基于大语言模型的人工智能系统存在许多安全性隐患,例如大语言模型系统容易受到难以被察觉的攻击,模型生成的内容存在违法、泄密、仇恨、偏见、错误等问题。并且在实际应用中,大语言模型可能被滥用,生成的内容可能引起国家、人群和领域等多个层面的困扰。本文旨在深入探讨大语言模型面临的安全性风险并进行分类,回顾现有的评估方法,研究安全性风险背后的因果机制,并总结现有的解决措施。具体而言,本文明确了大语言模型面临的10种安全性风险,并将其归类为模型自身安全性风险与生成内容的安全性风险两个方面,并对每种风险进行了详细的分析和讲解。此外,本文还从生命周期和危害程度两个角度对大语言模型的安全风险进行了系统化的分析,并介绍了现有的大语言模型安全风险评估方法、大语言模型安全风险的出现原因以及相应的缓解措施。大语言模型的安全风险是亟待解决的重要问题。 展开更多
关键词 大语言模型 模型自身安全性 生成内容安全性 安全性分类 安全性风险评估 安全性风险归因 安全性风险缓解措施 安全性研究展望
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妊娠晚期缺铁性贫血的危险因素和列线图预测模型 被引量:2
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作者 杨林 王亦雄 +1 位作者 潘辉 徐扬 《中山大学学报(医学科学版)》 北大核心 2025年第1期116-122,共7页
【目的】对孕妇妊娠期缺铁性贫血(IDA)的相关因素进行分析,根据其独立的危险因素,构建预测妊娠晚期缺铁性贫血的列线图预测模型,以期获得IDA的有效干预方案。【方法】将2022年7月—2023年12月在扬州市妇幼保健院定期产检的孕妇为调查对... 【目的】对孕妇妊娠期缺铁性贫血(IDA)的相关因素进行分析,根据其独立的危险因素,构建预测妊娠晚期缺铁性贫血的列线图预测模型,以期获得IDA的有效干预方案。【方法】将2022年7月—2023年12月在扬州市妇幼保健院定期产检的孕妇为调查对象,采取统一调查问卷结合监测血常规的方法跟踪孕妇直至分娩,入组500例,最终完成482例。根据孕晚期有无IDA分为IDA组与非IDA组。对可能影响缺铁性贫血的危险因素进行单因素分析及多因素logistic回归分析,并采用R软件建立预测发生的列线图模型。【结果】482例妊娠晚期女性发生IDA有96例,发生率为19.92%;单因素分析显示,经济独立情况、孕前体质指数、孕次及孕期有无正规补铁与妊娠晚期IDA的发生有关,差异均有统计学意义(P<0.05)。多因素Logistic回归分析显示,经济独立(P=0.031,OR=0.583)、孕期正规补铁(P<0.001,OR=5.337)是IDA的保护因素;孕前低体质指数(P=0.021,OR=2.375),孕次≥3次(P=0.015,OR=2.253)是IDA的危险因素。ROC曲线显示,列线图模型预测IDA发生的曲线下面积为0.84,最佳截断值为-1.481,预测灵敏度为81.2%,特异度分别为75.1%。【结论】妊娠晚期IDA发病率较高;孕前低体质指数、孕次大于3次是妊娠晚期IDA的危险因素;经济独立、正规补铁是妊娠晚期IDA的保护因素。可利用上述因素构建预测模型、采取预防性措施研究降低妊娠晚期IDA发病率的可行性方案。 展开更多
关键词 妊娠晚期 缺铁性贫血 危险因素 保护因素 列线图 预测模型
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基于LASSO-QVAR模型的中国金融机构尾部关联网络特征与系统性风险研究 被引量:1
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作者 许启发 蒋翠侠 汤彬彬 《统计与信息论坛》 北大核心 2025年第3期56-72,共17页
基于LASSO-QVAR模型,筛选金融机构之间有效关联,构建有向加权尾部关联网络,可以从系统视角揭示系统性风险动态特征。一方面,通过尾部关联网络构造系统性风险计分及其贡献,以度量系统性风险水平与识别系统重要性金融机构,进一步从微观层... 基于LASSO-QVAR模型,筛选金融机构之间有效关联,构建有向加权尾部关联网络,可以从系统视角揭示系统性风险动态特征。一方面,通过尾部关联网络构造系统性风险计分及其贡献,以度量系统性风险水平与识别系统重要性金融机构,进一步从微观层面探究系统性风险贡献的影响机制;另一方面,将尾部关联网络区分为正关联网络与负关联网络,分别提取网络整体特征以及网络节点特征,考察不同关联关系下网络特征的系统性风险预测能力。以2011—2022年32家中国A股上市金融机构作为研究对象,开展了实证研究。研究结果显示:第一,尾部关联网络具有时变特征,能够较好地吻合一些危机事件,银行业和证券业呈现出更为紧密的关联性,具有行业异质性。进一步,发现银行业风险共振(正关联网络)与风险分散(负关联网络)功能相较其他金融行业更强。第二,系统性风险计分可以作为量化系统性风险动态性的重要指标,系统性风险贡献主要集中于银行业与保险业,进一步机制分析表明公司治理水平能够显著影响到系统性风险贡献。第三,尾部关联网络特征具有很好的预测能力,网络整体特征能够预测系统性风险大小,网络节点特征能够预测金融机构系统性风险贡献。 展开更多
关键词 系统性风险 尾部关联网络 风险计分 LASSO-QVAR模型 金融机构
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融合多源混频不确定性信息的油价波动驱动因素 被引量:2
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作者 刘畅 申怡然 +1 位作者 孙晓蕾 张海颖 《系统管理学报》 北大核心 2025年第2期296-311,共16页
研究将多源不确定性指标纳入传统油价波动影响因素的分析框架,对国际油价波动的驱动因素进行了量化分析。综合考虑宏观经济变量、供需基本面因素、投机因素等传统油价驱动因素,以及经济政策不确定性、政治不确定性和金融市场不确定性等... 研究将多源不确定性指标纳入传统油价波动影响因素的分析框架,对国际油价波动的驱动因素进行了量化分析。综合考虑宏观经济变量、供需基本面因素、投机因素等传统油价驱动因素,以及经济政策不确定性、政治不确定性和金融市场不确定性等多源不确定性因素,基于单因子和双因子GARCH-MIDAS模型,考察了各因素对国际油价波动的影响及其差异特征。实证结果表明:供需因素对油价波动存在显著的异质性影响,传统变量仍是影响油价波动的主要驱动力;不确定性因素对长期油价波动的影响不容忽视,全球及主要国家的经济政策不确定性上升将推升原油市场的波动。此外,相较于基准GARCH模型,纳入不确定性指标的混频数据模型表现更优,传统变量与不确定性指标的结合对油价波动具有更强的解释能力。上述结论为投资者、市场监管者等利益相关方有效应对原油市场的各类风险提供了参考。 展开更多
关键词 原油价格波动 经济政策不确定性 地缘政治风险 GARCH-MIDAS模型
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胰十二指肠切除术术后肺部感染的危险因素分析及预测模型构建 被引量:1
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作者 杨鹏 许伊蒙 韩玮 《实用医学杂志》 北大核心 2025年第11期1705-1710,共6页
目的 探讨分析胰十二指肠切除术(PD)后肺部感染的危险因素并构建预测模型以指导临床早期干预。方法 回顾性纳入2022年1月至2024年10月新疆医科大学第一附属医院行PD的220例患者,排除术前肺部感染、资料不全及围手术期死亡病例。收集术... 目的 探讨分析胰十二指肠切除术(PD)后肺部感染的危险因素并构建预测模型以指导临床早期干预。方法 回顾性纳入2022年1月至2024年10月新疆医科大学第一附属医院行PD的220例患者,排除术前肺部感染、资料不全及围手术期死亡病例。收集术前、术中及术后临床资料,通过单因素分析筛选潜在危险因素,采用多因素logistic回归确定独立危险因素,并构建列线图预测模型。结果 84例(38.2%)患者发生术后肺部感染。多因素分析显示,高BMI(OR=1.12,95%CI:1.02~1.23,P <0.05)、术后3 d低白蛋白(OR=0.91,95%CI:0.83~0.99,P <0.05)、术后腹腔引流管留置时间长(OR=1.05,95%CI:1.01~1.09,P <0.05)、术后卧床时间长(OR=1.56,95%CI:1.22~1.99,P <0.05)以及术后发生肺部以外的并发症(OR=2.23,95%CI:1.05~4.75,P <0.05)是PD术后肺部感染的独立危险因素。预测模型AUC为0.82(95%CI:0.76~0.88),校准曲线显示拟合良好,内部验证后AUC为0.80(95%CI:0.71~0.88),模型有较好的预测能力。结论 高BMI、术后白蛋白水平低、术后腹腔引流管留置时间长、术后卧床时间长及术后发生肺部以外的并发症是PD术后肺部感染的独立危险因素,构建的风险预测模型对PD患者术后肺部感染的发生具有良好的预测效能。 展开更多
关键词 胰十二指肠切除术 术后肺部感染 危险因素 预测模型
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急性肺栓塞合并右心功能不全患者进入重症监护室的相关危险因素分析及风险预测 被引量:1
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作者 付春 朱凤雪 +5 位作者 陈源源 李纾 赵秀娟 姜娟 王振洲 刘健 《中国心血管杂志》 北大核心 2025年第1期45-51,共7页
目的探讨中、高危急性肺栓塞(APE)合并右心功能不全(RVD)患者的临床特征,分析他们进入重症监护室(ICU)的独立危险因素并建立风险预测模型。方法单中心、回顾性研究。连续纳入2012年12月至2022年12月于北京大学人民医院经CT肺动脉造影(CT... 目的探讨中、高危急性肺栓塞(APE)合并右心功能不全(RVD)患者的临床特征,分析他们进入重症监护室(ICU)的独立危险因素并建立风险预测模型。方法单中心、回顾性研究。连续纳入2012年12月至2022年12月于北京大学人民医院经CT肺动脉造影(CTPA)确诊为中、高危APE合并RVD的住院患者共92例,其中男性42例、女性50例,平均年龄(67.3±10.9)岁。根据是否收治ICU分为入ICU组(31例)和未入ICU组(61例),收集两组患者的一般资料、临床特征、生化检查和影像学指标。多因素logistic回归分析影响APE合并RVD患者进入ICU的独立危险因素,并建立风险预测模型。采用受试者工作特征(ROC)曲线评价相关指标对APE合并RVD患者进入ICU的预测价值,ROC曲线下面积(AUC)评价模型的预测准确性。结果与未入ICU组比较,入ICU组患者的心率和呼吸频率较快、收缩压(SBP)和舒张压(DBP)较低,心功能指标中B型利钠肽(BNP)、高敏肌钙蛋白I(hs-cTnI)和肺动脉收缩压(PASP)较高以及左心室射血分数(LVEF)较低,凝血功能指标中D-二聚体(D-dimer)较高,合并创伤/骨折病史比例较高(均为P<0.05)。多因素logistic回归分析显示,SBP、BNP、hs-cTnI、PASP和D-dimer是影响APE合并RVD患者进入ICU的独立危险因素(均为P<0.05)。ROC曲线分析显示,当APE合并RVD患者的SBP>119 mmHg(AUC=0.879,95%CI:0.811~0.947)时进入ICU可能性降低,BNP>416 pg/ml(AUC=0.996,95%CI:0.988~1.000)、hs-cTnI>321.15 pg/ml(AUC=0.801,95%CI:0.694~0.907)、D-dimer>686 ng/ml(AUC=0.852,95%CI:0.771~0.933)和PASP>41 mmHg(AUC=0.967,95%CI:0.905~1.000)时进入ICU可能性增加(均为P<0.001)。根据上述指标是否为高优或低优指标进行赋值,并建立风险预测模型,即Score1模型(取值范围[0,5]),截断点值为3分(AUC=0.999,95%CI:0.996~1.000,P<0.001),即当APE合并RVD患者的Score1≤3分时,患者进入ICU的可能性增加;当APE合并RVD患者的Score1>3分时,患者进入ICU的可能性降低。结论SBP、BNP、hs-cTnI、PASP和D-dimer是影响APE合并RVD患者进入ICU的独立危险因素,由此构建的风险预测模型对APE合并RVD患者进入ICU有良好的预测价值。 展开更多
关键词 急性肺栓塞 右心功能不全 重症监护室 危险因素 预测模型
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基于信息量模型的黑山峡地区滑坡易发性风险评价 被引量:3
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作者 王炳亮 裴超 +2 位作者 李宝泉 石慧群 林兴 《人民黄河》 北大核心 2025年第1期134-140,共7页
滑坡是黄河黑山峡地区的主要地质灾害之一,在黑山峡水利枢纽建设前期工作中开展黑山峡地区滑坡易发性评价显得尤为必要。基于黑山峡地区地质条件、气候、人类活动等调查资料,选取高程、坡度、曲率、地层岩性、与断层的距离、与水系的距... 滑坡是黄河黑山峡地区的主要地质灾害之一,在黑山峡水利枢纽建设前期工作中开展黑山峡地区滑坡易发性评价显得尤为必要。基于黑山峡地区地质条件、气候、人类活动等调查资料,选取高程、坡度、曲率、地层岩性、与断层的距离、与水系的距离、NDVI(归一化差分植被指数)、与道路的距离、降水量9个因子作为滑坡易发性评价指标,采用信息量模型进行滑坡易发性评价,通过对各因子的分级权重进行计算,得到滑坡易发性信息量值;通过对滑坡易发性信息量进行叠加与分区,绘制黑山峡地区滑坡易发性分区图,确定危险区域。结果表明:黑山峡地区滑坡灾害极高易发区位于东北部中卫市沙坡头区、南部靖远县以及主要河流与道路沿线,这些地区地层岩性较软弱,大多为砂、黄土等,在河流冲积与人类活动的影响下极易发生地表斜坡失稳。 展开更多
关键词 滑坡 易发性 风险评价 信息量模型 黑山峡地区
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