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Belief exponential divergence for D-S evidence theory and its application in multi-source information fusion 被引量:1
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作者 DUAN Xiaobo FAN Qiucen +1 位作者 BI Wenhao ZHANG An 《Journal of Systems Engineering and Electronics》 CSCD 2024年第6期1454-1468,共15页
Dempster-Shafer evidence theory is broadly employed in the research of multi-source information fusion.Nevertheless,when fusing highly conflicting evidence it may pro-duce counterintuitive outcomes.To address this iss... Dempster-Shafer evidence theory is broadly employed in the research of multi-source information fusion.Nevertheless,when fusing highly conflicting evidence it may pro-duce counterintuitive outcomes.To address this issue,a fusion approach based on a newly defined belief exponential diver-gence and Deng entropy is proposed.First,a belief exponential divergence is proposed as the conflict measurement between evidences.Then,the credibility of each evidence is calculated.Afterwards,the Deng entropy is used to calculate information volume to determine the uncertainty of evidence.Then,the weight of evidence is calculated by integrating the credibility and uncertainty of each evidence.Ultimately,initial evidences are amended and fused using Dempster’s rule of combination.The effectiveness of this approach in addressing the fusion of three typical conflict paradoxes is demonstrated by arithmetic exam-ples.Additionally,the proposed approach is applied to aerial tar-get recognition and iris dataset-based classification to validate its efficacy.Results indicate that the proposed approach can enhance the accuracy of target recognition and effectively address the issue of fusing conflicting evidences. 展开更多
关键词 Dempster-Shafer(D-S)evidence theory multi-source information fusion conflict measurement belief expo-nential divergence(BED) target recognition
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Chemical Reactivity Description in Density-Functional and Information Theories 被引量:2
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作者 NALEWAJSKI Roman F. 《物理化学学报》 SCIE CAS CSCD 北大核心 2017年第12期2491-2509,共19页
In Quantum Information Theory(QIT) the classical measures of information content in probability distributions are replaced by the corresponding resultant entropic descriptors containing the nonclassical terms generate... In Quantum Information Theory(QIT) the classical measures of information content in probability distributions are replaced by the corresponding resultant entropic descriptors containing the nonclassical terms generated by the state phase or its gradient(electronic current). The classical Shannon(S[p]) and Fisher(I[p]) information terms probe the entropic content of incoherent local events of the particle localization, embodied in the probability distribution p, while their nonclassical phase-companions, S[ Φ ] and I[ Φ ], provide relevant coherence information supplements.Thermodynamic-like couplings between the entropic and energetic descriptors of molecular states are shown to be precluded by the principles of quantum mechanics. The maximum of resultant entropy determines the phase-equilibrium state, defined by "thermodynamic" phase related to electronic density,which can be used to describe reactants in hypothetical stages of a bimolecular chemical reaction.Information channels of molecular systems and their entropic bond indices are summarized, the complete-bridge propagations are examined, and sequential cascades involving the complete sets of the atomic-orbital intermediates are interpreted as Markov chains. The QIT description is applied to reactive systems R = A―B, composed of the Acidic(A) and Basic(B) reactants. The electronegativity equalization processes are investigated and implications of the concerted patterns of electronic flows in equilibrium states of the complementarily arranged substrates are investigated. Quantum communications between reactants are explored and the QIT descriptors of the A―B bond multiplicity/composition are extracted. 展开更多
关键词 Density-functional theory Donor-acceptor system Electronegativity equalization and electron flows information theory Markov chains PHASE-EQUILIBRIA
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Threat sequencing of multiple UCAVs with incomplete information based on game theory 被引量:4
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作者 LI Shouyi CHEN Mou +1 位作者 WU Qingxian WANG Yuhui 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2022年第4期986-996,共11页
The threat sequencing of multiple unmanned combat air vehicles(UCAVs) is a multi-attribute decision-making(MADM)problem. In the threat sequencing process of multiple UCAVs,due to the strong confrontation and high dyna... The threat sequencing of multiple unmanned combat air vehicles(UCAVs) is a multi-attribute decision-making(MADM)problem. In the threat sequencing process of multiple UCAVs,due to the strong confrontation and high dynamics of the air combat environment, the weight coefficients of the threat indicators are usually time-varying. Moreover, the air combat data is difficult to be obtained accurately. In this study, a threat sequencing method of multiple UCAVs is proposed based on game theory by considering the incomplete information. Firstly, a zero-sum game model of decision maker( D) and nature(N)with fuzzy payoffs is established to obtain the uncertain parameters which are the weight coefficient parameters of the threat indicators and the interval parameters of the threat matrix. Then,the established zero-sum game with fuzzy payoffs is transformed into a zero-sum game with crisp payoffs(matrix game) to solve. Moreover, a decision rule is addressed for the threat sequencing problem of multiple UCAVs based on the obtained uncertain parameters. Finally, numerical simulation results are presented to show the effectiveness of the proposed approach. 展开更多
关键词 threat sequencing multiple unmanned combat air vehicles(UCAVs) multi-attribute decision-making(MADM) game theory incomplete information
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An Information Theory Approach to the Data Compression and Imaging System for Synthetic Aperture Radar (SAR)
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作者 Xiao Yongxin Peng Hailiang and Chen Zongzhi(Institute of Electronics, Chinese Academy of Sciences, Beijing 100080, P. R. China.) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1995年第1期1-15,共15页
Synthetic aperture radar (SAR) is portrayed as a multiple access channel. An information theory approach is applied to the SAR imaging system, and the information content about a target that can be extracted from its ... Synthetic aperture radar (SAR) is portrayed as a multiple access channel. An information theory approach is applied to the SAR imaging system, and the information content about a target that can be extracted from its radar image is evaluated by the average mutual information measure. A conditional (transition) probability density function (PDF) of the SAR imaging system is derived by analyzing the system and a closed form of the information content is found. It is shown that the information content obtained by the SAR imaging system from an independent sample of echoes will decrease and the total information content obtained by the SAR imaging system will increase with an increase in the number of looks. Because the total average mutual information is also used to define a measure of radiometric resolution for radar images, it is shown that the radiometric resolution of a radar image of terrain will be improved by spatial averaging. In addition, the imaging process and the data compression process for SAR are each treated as an independent generalized communication channel. The effects of data compression upon radiometric resolution for SAR are studied and some conclusions are obtained. 展开更多
关键词 Synthetic aperture radar (SAR) information theory data compression radiometric resolution probability density function (PDF) multiple access channel average mutual information
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论集成管理理论在Information Commons构建中的应用——Information Commons构建的理论基础研究之三 被引量:4
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作者 陆宝益 《图书与情报》 CSSCI 北大核心 2011年第4期27-30,35,共5页
将集成思想和方法创造性地应用于管理实践过程的集成管理理论是现代组织管理中的重要理论,作为一个具有高度集成化特征的复杂系统的IC,从规划、实施到运行服务,在功能与服务的设置、信息资源的配备、技术的运用和系统的设计、人才智力... 将集成思想和方法创造性地应用于管理实践过程的集成管理理论是现代组织管理中的重要理论,作为一个具有高度集成化特征的复杂系统的IC,从规划、实施到运行服务,在功能与服务的设置、信息资源的配备、技术的运用和系统的设计、人才智力资源的配置等多个方面,均自觉或不自觉地运用了集成的思想、方法和技术,集成管理的思想是其建设的重要指导思想。IC构建过程中的各个环节,都不同程度地蕴含着集成管理理论的思想内涵。 展开更多
关键词 信息共享空间 集成管理理论 数字图书馆
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Power allocation for MIMO-OFDM systems with multi-user decoupling and scheduling
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作者 段世平 徐友云 宋文涛 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第3期715-720,F0003,共7页
A power allocation scheme for multi-user multiple-input multiple-output orthogonal frequency division multiplexing (MI- MO-OFDM) systems with channel state information (CSI) on transmitter and receiver is pressed.... A power allocation scheme for multi-user multiple-input multiple-output orthogonal frequency division multiplexing (MI- MO-OFDM) systems with channel state information (CSI) on transmitter and receiver is pressed. Multi-user lower allocation can be decoupled into single user lower allocation throughout null space mapping of multi-user channel and lower allocation can be performed throughout spatial-spectral water-filling for per user.To deal with more users in system and fading correlation,scheduling is oerformed to maintain the gain of power allocation.The proposed scheme can substantially improve system's spectral efficiency with low complexity.Simulation results validate the accuracy of theoretic analyses. 展开更多
关键词 power allocation multi-user information theory radio resource management MIMO OFDM.
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Information Commons的结构及其模型研究 被引量:2
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作者 陆宝益 《图书情报知识》 CSSCI 北大核心 2011年第5期101-108,共8页
IC的理论构成可划分为物理空间、虚拟空间、政策空间和情感空间等四个维面/方面。从建设所涉及的范围及其功能的发挥等因素考虑,IC分为宏观层次上的全球IC巨/型IC、中观层次上的区域/系统IC和微观层次上的机构/组织IC等三大类型。不同... IC的理论构成可划分为物理空间、虚拟空间、政策空间和情感空间等四个维面/方面。从建设所涉及的范围及其功能的发挥等因素考虑,IC分为宏观层次上的全球IC巨/型IC、中观层次上的区域/系统IC和微观层次上的机构/组织IC等三大类型。不同层次类型的IC,具有不同的功能与特点,其结构模型也各不相同。 展开更多
关键词 信息共享空间 数字图书馆 理论构成 结构模型
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Data processing of small samples based on grey distance information approach 被引量:14
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作者 Ke Hongfa, Chen Yongguang & Liu Yi 1. Coll. of Electronic Science and Engineering, National Univ. of Defense Technology, Changsha 410073, P. R. China 2. Unit 63880, Luoyang 471003, P. R. China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第2期281-289,共9页
Data processing of small samples is an important and valuable research problem in the electronic equipment test. Because it is difficult and complex to determine the probability distribution of small samples, it is di... Data processing of small samples is an important and valuable research problem in the electronic equipment test. Because it is difficult and complex to determine the probability distribution of small samples, it is difficult to use the traditional probability theory to process the samples and assess the degree of uncertainty. Using the grey relational theory and the norm theory, the grey distance information approach, which is based on the grey distance information quantity of a sample and the average grey distance information quantity of the samples, is proposed in this article. The definitions of the grey distance information quantity of a sample and the average grey distance information quantity of the samples, with their characteristics and algorithms, are introduced. The correlative problems, including the algorithm of estimated value, the standard deviation, and the acceptance and rejection criteria of the samples and estimated results, are also proposed. Moreover, the information whitening ratio is introduced to select the weight algorithm and to compare the different samples. Several examples are given to demonstrate the application of the proposed approach. The examples show that the proposed approach, which has no demand for the probability distribution of small samples, is feasible and effective. 展开更多
关键词 Data processing Grey theory Norm theory Small samples Uncertainty assessments Grey distance measure information whitening ratio.
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Multi-sources information fusion algorithm in airborne detection systems 被引量:19
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作者 Yang Yan Jing Zhanrong Gao Tan Wang Huilong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第1期171-176,共6页
To aim at the multimode character of the data from the airplane detecting system, the paper combines Dempster- Shafer evidence theory and subjective Bayesian algorithm and makes to propose a mixed structure multimode ... To aim at the multimode character of the data from the airplane detecting system, the paper combines Dempster- Shafer evidence theory and subjective Bayesian algorithm and makes to propose a mixed structure multimode data fusion algorithm. The algorithm adopts a prorated algorithm relate to the incertitude evaluation to convert the probability evaluation into the precognition probability in an identity frame, and ensures the adaptability of different data from different source to the mixed system. To guarantee real time fusion, a combination of time domain fusion and space domain fusion is established, this not only assure the fusion of data chain in different time of the same sensor, but also the data fusion from different sensors distributed in different platforms and the data fusion among different modes. The feasibility and practicability are approved through computer simulation. 展开更多
关键词 information fusion Dempster-Shafer evidence theory Subjective Bayesian algorithm Airplane detecting system
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Empirical Study of the Usage of Mobile Information Service in Rural Area Base on the UTAUT Model 被引量:1
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作者 Chen Limei Chen Dongping 《学术界》 CSSCI 北大核心 2019年第8期207-216,共10页
Based on the UTAUT model,this article introduces three variables including perceived cost,information quality and hedonic motives,and using the level of education as a moderator variable,to build an acceptance model o... Based on the UTAUT model,this article introduces three variables including perceived cost,information quality and hedonic motives,and using the level of education as a moderator variable,to build an acceptance model of mobile information service system in rural area.Based on the household survey obtaining firsthand data of 961 farmers in Jiangsu Province,the study tests the improved UTAUT model by using Amos22.0 software.The results show that compared with the original UTAUT model,improved UTAUT model willingness to accept the explanatory power get further increase(from 49.0%to 61.9%).Performance expectations,social impact,information quality have significant positive influence on accepting intend,hedonic motives have a significant negative impact to accept in-tend,convenient conditions directly affect the use of behavior;gender and level of education has a regulating effect to accept intention.Through further grouping path analysis,the result shows that hedonic motives have broader impacts for women farmers accept mobile information services.Compared with other groups,only farmers with primary education are easily afected by others,and farmers with college education or above are more easily afectede by information quality.Finally,this paper explains the results and puts forward countermeasures and suggestions accordingly. 展开更多
关键词 rural mobile information services UNIFIED theory of ACCEPTANCE and use of technology(UTAUT) REGULATING effect
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Which Information Theoretic Quantity Should We Choose for Steric Analysis of Water Nanoclusters(H2O)n(n=6,32,64)?
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作者 ALIPOUR Mojtaba 《物理化学学报》 SCIE CAS CSCD 北大核心 2018年第4期407-413,共7页
As evidenced from recent literature,interest in employing information theory measures for understanding different properties of atomic and molecular systems is increasing tremendously.Following our earlier efforts in ... As evidenced from recent literature,interest in employing information theory measures for understanding different properties of atomic and molecular systems is increasing tremendously.Following our earlier efforts in this field,we here evaluate the feasibility of using information theory functionals such as Fisher information,Shannon entropy,Onicescu information energy,and Ghosh-Berkowitz-Parr entropy as measures of steric effects for the steric analysis of water nanoclusters.Taking the structural isomers of water hexamers as working models and using information theoretic quantities,we show that the relative energies of water nanoclusters and the computed steric energies are related.We also show the strong effects of steric repulsion on conformational stabilities.At the same time,we have also assessed the usefulness of simultaneously considering the different information theoretic quantities,and achieved more accurate descriptions of the stability of water nanoclusters.In order to consider the effects of cluster size on the obtained results and the extent of applicability of information theoretic quantities,we have also benchmarked larger water nanoclusters with 32 and 64 units.Scrutinizing the obtained data from information theory functionals,we found that Fisher information shows the best overall performance.Our findings underline that the information theoretic quantities,especially Fisher information,can be used as quantitative measures of relative energies and consequently the order of stability of nanoclusters,which affirmed the utility of information theory for investigating various physical and chemical problems. 展开更多
关键词 物理学 化学 教材 高校
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ESG信息披露双元动机对企业绿色创新绩效的影响——绿色形象的中介作用与价值认知的调节作用 被引量:4
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作者 刘军伟 梁秋宸 刘华 《科技进步与对策》 北大核心 2025年第1期113-121,共9页
ESG信息披露是驱动企业绿色创新发展的重要动力。由此,如何通过激发企业ESG信息披露动机促进其绿色创新绩效提升引起学界关注。基于动机理论、信号传递理论与环境心理学理论,构建ESG信息披露双元动机、绿色形象、价值认知与绿色创新绩... ESG信息披露是驱动企业绿色创新发展的重要动力。由此,如何通过激发企业ESG信息披露动机促进其绿色创新绩效提升引起学界关注。基于动机理论、信号传递理论与环境心理学理论,构建ESG信息披露双元动机、绿色形象、价值认知与绿色创新绩效关系概念模型,以绿色形象为中介变量,以管理层价值认知为调节变量,探讨ESG信息披露双元动机对企业绿色创新绩效的作用机制。通过对254份企业问卷调查数据进行实证分析,结果发现:ESG信息披露的利己性动机与利他性动机对企业绿色创新绩效具有显著正向影响;绿色形象在ESG信息披露双元动机与企业绿色创新绩效间发挥中介作用;价值认知正向调节ESG信息披露双元动机与绿色创新绩效的关系。结论可为企业绿色创新提供指导,为政府制定ESG信息披露政策提供参考。 展开更多
关键词 ESG信息披露 企业绿色创新绩效 绿色形象 价值认知 动机理论
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基于氢能固态运输的电-氢综合能源系统双层调度模型 被引量:3
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作者 谭洪 王宇炜 +2 位作者 王秋杰 李辉 李振兴 《电工技术学报》 北大核心 2025年第3期744-758,共15页
中短距离氢能运输需求下,长管拖车运氢具有较好的经济性,但长管拖车的储氢密度低,且高压氢气存在爆炸和泄漏等风险。为此,该文提出一种基于氢能固态运输的电-氢综合能源系统(EHIES)双层调度模型。首先,通过分析金属固态储氢机理,并利用... 中短距离氢能运输需求下,长管拖车运氢具有较好的经济性,但长管拖车的储氢密度低,且高压氢气存在爆炸和泄漏等风险。为此,该文提出一种基于氢能固态运输的电-氢综合能源系统(EHIES)双层调度模型。首先,通过分析金属固态储氢机理,并利用氢能气-固两相转换过程中压强与反应温度关系,构建氢能固态运载车(HSTV)的装卸模型;其次,采用改进含时间窗车辆路径问题构建HSTV的运输模型;最后,基于隶属度的信息间隙决策理论(M-IGDT)建立EHIES日前双层调度模型,并将所提双层模型转换成单层模型求解。采用改进的IEEE 118和IEEE300系统进行仿真,结果表明氢能固态运输能有效地提升氢能运输效率和系统经济性。 展开更多
关键词 电-氢综合能源系统 氢能固态运输 信息间隙决策理论 双层调度
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高管媒体背景有助于提升企业ESG信息披露质量吗? 被引量:1
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作者 常莹莹 陈秀雯 林向荣 《南京审计大学学报》 北大核心 2025年第2期45-54,共10页
基于高层梯队理论和烙印理论,以2009—2022年A股上市公司为研究样本,实证检验了高管媒体背景对企业ESG信息披露质量的影响。研究表明,高管媒体背景显著抑制了企业ESG信息披露质量,该结论经过一系列稳健性和内生性检验后依然成立。进一... 基于高层梯队理论和烙印理论,以2009—2022年A股上市公司为研究样本,实证检验了高管媒体背景对企业ESG信息披露质量的影响。研究表明,高管媒体背景显著抑制了企业ESG信息披露质量,该结论经过一系列稳健性和内生性检验后依然成立。进一步研究结果表明,高管持股比例越高,高管媒体背景对企业ESG信息披露质量的抑制作用越显著;CEO类的高管媒体背景和非政府宣传部门类高管媒体背景对企业ESG信息披露质量的抑制作用更显著;相比于国有企业,非国有企业的高管媒体背景对企业ESG信息披露质量的抑制作用更突出。 展开更多
关键词 高管特征 媒体背景 ESG信息披露质量 信息环境透明度 烙印理论 高层梯队理论
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基于D-S证据理论的多智能体系统冲突数据融合机制研究 被引量:1
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作者 王娜 刘静渝 +1 位作者 李皓然 夏晓峰 《重庆大学学报》 北大核心 2025年第2期22-34,共13页
多智能体信息融合(multi-agent information fusion,MAIF)系统主要面向多个智能体之间的信息融合、调节、交流和矛盾处理。研究针对数据高度冲突条件下的D-S证据理论失效问题,提出一种将重构的基本概率分配和信念熵相结合的多智能体系... 多智能体信息融合(multi-agent information fusion,MAIF)系统主要面向多个智能体之间的信息融合、调节、交流和矛盾处理。研究针对数据高度冲突条件下的D-S证据理论失效问题,提出一种将重构的基本概率分配和信念熵相结合的多智能体系统冲突数据融合方法。该方法使用重构的基本概率分配和信念熵修正证据的可靠性,获得更合理的证据,使用Dempster组合规则将证据进行融合得到结果,在2个实验中均得到了超过90%的置信度。实验表明了该方法的有效性,提高了MAIF系统辨识过程的精度。 展开更多
关键词 基本概率分配 D-S证据理论 多智能体 信息融合
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基于SP-IGDT的港口岸电混合能源系统氢储能容量配置 被引量:1
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作者 王树东 徐十伟 唐伟强 《中国航海》 北大核心 2025年第1期115-123,共9页
船舶在靠港期间使用柴油辅机会造成大量化石能源消耗和污染物排放,利用岸电供能是很好的替代方案。针对岸电系统能源问题文章引入海上风机、岸电与氢基储能组成的混合能源系统,提出一种基于混合随机规化(SP)-信息间隙决策理论(IGDT)的... 船舶在靠港期间使用柴油辅机会造成大量化石能源消耗和污染物排放,利用岸电供能是很好的替代方案。针对岸电系统能源问题文章引入海上风机、岸电与氢基储能组成的混合能源系统,提出一种基于混合随机规化(SP)-信息间隙决策理论(IGDT)的氢基储能规划模型。针对海上风机出力不确定性,采用随机规划得到时序典型出力场景;针对岸电靠港船舶负荷和岸电价格概率分布难以准确刻画,采用IGDT形成双目标模型处理两者不确定性,以及引入两种不同风险策略规划模型和考虑季节性因素对其进行分析。算例结果表明,混合能源系统可提高能源利用率及互动性,为决策者提供规划依据,验证了所提模型的有效性。 展开更多
关键词 岸电 混合能源系统 容量配置 多元不确定性 随机规划-信息间隙决策理论
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区块链应用能否促进产学研合作——来自中国制造业上市公司的经验证据 被引量:1
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作者 李常洪 王海艳 郭嘉琦 《科技进步与对策》 北大核心 2025年第10期38-47,共10页
基于2016—2022年中国沪深A股制造业上市公司面板数据,从开放悖论视角考察企业区块链应用对产学研合作的影响,并结合非正式制度和动态能力理论剖析信任的中介作用以及吸收能力的调节作用。研究发现:①企业区块链应用能促进产学研合作,... 基于2016—2022年中国沪深A股制造业上市公司面板数据,从开放悖论视角考察企业区块链应用对产学研合作的影响,并结合非正式制度和动态能力理论剖析信任的中介作用以及吸收能力的调节作用。研究发现:①企业区块链应用能促进产学研合作,且在大企业、国有企业和衰退期企业中更为显著;②机制检验表明,企业区块链应用主要通过信任增强效应,推动产学研合作;③进一步分析发现,企业借助区块链不仅可以构建陌生人关系网络内的信任机制,而且在熟人关系网络中更能实现情感信任与数字信任的双重加固,从而有力助推产学研合作;④吸收能力能增强企业区块链应用与产学研合作之间的关系,且该调节作用部分通过信任增强效应实现。研究结论为数字化时代下区块链应用驱动产学研深度融合提供有益启示。 展开更多
关键词 区块链应用 产学研合作 开放悖论 非正式制度视角 动态能力理论
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债券风险信息披露与债券信用利差——基于信息锚定机制的U型关系新解
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作者 张军 于瑶 杨策 《财经问题研究》 北大核心 2025年第4期115-128,F0003,共15页
现有研究指出,投资者对债券募集说明书中的风险信息披露持“风险观”。为进一步挖掘风险信息披露的定价反应,本文以2010—2021年中国上市公司发行的一般公司债为研究对象,基于对债券募集说明书“风险因素”章节中风险词汇的文本分析,通... 现有研究指出,投资者对债券募集说明书中的风险信息披露持“风险观”。为进一步挖掘风险信息披露的定价反应,本文以2010—2021年中国上市公司发行的一般公司债为研究对象,基于对债券募集说明书“风险因素”章节中风险词汇的文本分析,通过构建非线性模型研究债券风险信息披露对债券信用利差的影响。研究发现,债券风险信息披露与债券信用利差之间存在U型关系。异质性分析发现,债券风险信息披露与债券信用利差之间存在的U型关系在信息环境较好和公司业绩较好的样本中更显著。这些证据表明,除了传统的“风险观”外,还存在“信息观”。进一步研究证实,投资者会根据公开信息建立直接型或分析型风险信息锚。当债券风险信息披露位于“信息锚”的范围内时,表现为“信息观”;一旦超出这个范围,则转为“风险观”。但在分析型风险信息锚的研究中发现,投资者仅对预期内的内部风险信息披露表现出“信息观”,对预期内的外部风险信息披露并不敏感。本文为有效降低债券发行方的融资成本、提升市场监管部门的监督水平提供了理论支持。 展开更多
关键词 债券风险信息披露 债券信用利差 前景理论 信息锚定理论
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高管信息技术背景抑制了企业违规吗?
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作者 王生年 张楠 《经济经纬》 北大核心 2025年第3期120-132,共13页
基于2007—2023年A股上市公司数据,考察高管信息技术背景对企业违规的影响。研究表明:高管信息技术背景抑制了企业违规。影响机制表明,高管信息技术背景通过提高公司治理水平与缓解信息不对称,抑制了企业违规。异质性分析表明,在管理层... 基于2007—2023年A股上市公司数据,考察高管信息技术背景对企业违规的影响。研究表明:高管信息技术背景抑制了企业违规。影响机制表明,高管信息技术背景通过提高公司治理水平与缓解信息不对称,抑制了企业违规。异质性分析表明,在管理层持股、分析师关注较低及法制环境较差时,两者间的影响更为显著。进一步研究发现,从信息技术背景来源而言,高管信息技术背景的经验性烙印对企业违规的影响更为显著;从高管类型而言,管理层和董事的信息技术背景对企业违规的影响更为显著;从违规类型而言,高管信息技术背景对信息披露违规和经营违规的影响更为显著;从违规程度而言,高管信息技术背景对严重违规的影响更为显著。研究结论为高管特质与企业违规的研究提供了增量文献,有助于企业选聘信息技术背景高管以发挥其在防范治理违规行为中的作用。 展开更多
关键词 高管信息技术背景 企业违规 高阶梯队理论 信息不对称 烙印理论
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基于知情构造理论的单材料柔性机构拓扑优化
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作者 苏珂 王颖 +2 位作者 梁腾腾 魏义礼 张楠楠 《中国机械工程》 北大核心 2025年第4期873-881,共9页
针对柔性机构在拓扑优化过程中因设计子域数增加而使设计域外径与内径的子域交接点产生材料分布进而导致拓扑结构设计子域内优化空间过少影响结构整体性能的问题,基于知情构造理论提出了单材料柔性机构拓扑优化模型,该模型通过材料属性... 针对柔性机构在拓扑优化过程中因设计子域数增加而使设计域外径与内径的子域交接点产生材料分布进而导致拓扑结构设计子域内优化空间过少影响结构整体性能的问题,基于知情构造理论提出了单材料柔性机构拓扑优化模型,该模型通过材料属性的描述以及属性参数计算,使设计子域数的取值在适应材料特征与分布的基础上进行,保证了结构具有足够的优化空间。以机构的几何增益最大为目标,建立了基于无网格伽辽金法(EFG)的单材料柔性机构拓扑优化模型。在拓扑优化过程中引入无网格伽辽金法进行EFG相对密度场的构造,利用设计域中的EFG节点来构造变形函数,在预先完成材料属性有效描述的情况下节点能够灵活布局,避免出现数值不稳定的现象从而影响性能优化效果。对典型算例应力分布进行分析,验证了提出模型的有效性。 展开更多
关键词 知情构造理论 柔性机构 拓扑优化 材料属性描述
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