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Prospect Theory Based Individual Irrationality Modelling and Behavior Inducement in Pandemic Control
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作者 Wenxiang Dong H.Vicky Zhao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期139-170,共32页
Understanding and modeling individuals’behaviors during epidemics is crucial for effective epidemic control.However,existing research ignores the impact of users’irrationality on decision-making in the epidemic.Mean... Understanding and modeling individuals’behaviors during epidemics is crucial for effective epidemic control.However,existing research ignores the impact of users’irrationality on decision-making in the epidemic.Meanwhile,existing disease control methods often assume users’full compliance with measures like mandatory isolation,which does not align with the actual situation.To address these issues,this paper proposes a prospect theorybased framework to model users’decision-making process in epidemics and analyzes how irrationality affects individuals’behaviors and epidemic dynamics.According to the analysis results,irrationality tends to prompt conservative behaviors when the infection risk is low but encourages risk-seeking behaviors when the risk is high.Then,this paper proposes a behavior inducement algorithm to guide individuals’behaviors and control the spread of disease.Simulations and real user tests validate our analysis,and simulation results show that the proposed behavior inducement algorithm can effectively guide individuals’behavior. 展开更多
关键词 Disease spread behavior model IRRATIONALITY prospect theory
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Pt基催化剂上CO_(2)辅助丙烷脱氢的反应机理
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作者 杨倩 聂小娃 +1 位作者 丁凡舒 郭新闻 《石油学报(石油加工)》 EI CAS CSCD 北大核心 2024年第2期480-492,共13页
Pt基双金属是一种具有发展前景的丙烷脱氢催化剂,CO_(2)在Pt基催化剂上辅助丙烷脱氢的微观反应机理与优势能量路径尚不明确,为此,采用密度泛函理论(DFT)计算研究了Pt(111)表面及Pt3Mn(111)表面上丙烷直接脱氢反应(PDH)及CO_(2)辅助丙烷... Pt基双金属是一种具有发展前景的丙烷脱氢催化剂,CO_(2)在Pt基催化剂上辅助丙烷脱氢的微观反应机理与优势能量路径尚不明确,为此,采用密度泛函理论(DFT)计算研究了Pt(111)表面及Pt3Mn(111)表面上丙烷直接脱氢反应(PDH)及CO_(2)辅助丙烷脱氢反应(CO_(2)-ODH)的反应网络与关键步骤。计算结果表明:CO_(2)的加入可以降低PDH速控步骤的能垒,对于消耗表面H有利,促进了丙烷脱氢反应正向移动,有利于生成丙烯,从而改变了反应路径和反应动力学;CO_(2)在消除积炭反应中的能垒较高,但是Mn的引入有利于CO_(2)消除积炭。此外,第二金属组分Mn的引入,不但有利于产物丙烯脱附,还提高了C—C裂解能垒,从而提高了丙烯的选择性。 展开更多
关键词 丙烷脱氢 二氧化碳 辅助 pt基催化剂 密度泛函理论 反应机理
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Zn-Pt/ZSM-5催化CO_(2)辅助丙烷脱氢的密度泛函理论研究
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作者 屈姝良 樊华华 +2 位作者 聂小娃 丁凡舒 郭新闻 《石油学报(石油加工)》 EI CAS CSCD 北大核心 2024年第2期392-403,共12页
通过密度泛函理论(DFT)计算研究了Zn-Pt/ZSM-5催化丙烷脱氢的反应机理,筛选出最优能量途径。研究发现丙烷在Zn-Lewis和Pt-Lewis酸位点上具有不同的反应路径和限速步骤。Bader电荷计算结果表明,丙烷分子吸附后,[Zn-O-Pt]^(2+)活性位点中P... 通过密度泛函理论(DFT)计算研究了Zn-Pt/ZSM-5催化丙烷脱氢的反应机理,筛选出最优能量途径。研究发现丙烷在Zn-Lewis和Pt-Lewis酸位点上具有不同的反应路径和限速步骤。Bader电荷计算结果表明,丙烷分子吸附后,[Zn-O-Pt]^(2+)活性位点中Pt上的电子密度增加,有利于丙烷活化,Pt位点对H的吸引能力更强,导致Pt—H键断裂生成H_(2)需要克服较高能垒。Pt的引入改变了Zn/ZSM-5的电子性质,影响其催化剂性能。在反应体系中引入CO_(2)改变了丙烷脱氢反应路径,降低了限速步骤能垒,促进反应正向进行。 展开更多
关键词 丙烷脱氢 Zn-pt/ZSM-5 CO_(2)辅助 反应机理 密度泛函理论
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Cumulative prospect theory-based user equilibrium model with stochastic perception errors 被引量:1
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作者 WANG Wei SUN Hui-jun 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第9期2465-2474,共10页
The cumulative prospect theory(CPT) is applied to study travelers' route choice behavior in a degradable transport network. A cumulative prospect theory-based user equilibrium(CPT-UE) model considering stochastic ... The cumulative prospect theory(CPT) is applied to study travelers' route choice behavior in a degradable transport network. A cumulative prospect theory-based user equilibrium(CPT-UE) model considering stochastic perception error(SPE) within travelers' route choice decision process is developed. The SPE is conditionally dependent on the actual travel time distribution, which is different from the deterministic perception error used in the traditional logit-based stochastic user equilibrium. The CPT-UE model is formulated as a variational inequality problem and solved by a heuristic solution algorithm. Numerical examples are provided to illustrate the application of the proposed model and efficiency of the solution algorithm. The effects of SPE on the reference point determination, cumulative prospect value estimation, route choice decision and network performance evaluation are investigated. 展开更多
关键词 cumulative prospect theory user equilibrium stochastic perception error variational inequality
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The Evaluation of Alternative Risk Control Schemes Based on Cumulative Prospect Theory
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作者 Hai Zhao Yuliang Wang 《Journal of Architectural Research and Development》 2023年第6期17-22,共6页
Based on the analysis of the evaluation problems associated with the risk control scheme for major engineering projects,the evaluation method of the risk control scheme considering the irrational behavior of evaluatio... Based on the analysis of the evaluation problems associated with the risk control scheme for major engineering projects,the evaluation method of the risk control scheme considering the irrational behavior of evaluation members in fuzzy random environment is proposed.Firstly,a maximum entropy model corresponding to any evaluation member is es-tablished by using triangular fuzzy random variables and grey correlation coefficient in order to obtain the weight of each risk factor of the member.Secondly,a nonlinear programming model is established according to the principle of minimiz-ing deviation to estimate the weight of different evaluation members on the evaluation of alternative risk control schemes.Lastly,the cumulative entropy model is used to calculate the weight of risk control schemes.Cumulative prospect theory obtains the comprehensive prospect utility value of each alternative to determine the optimal alternative. 展开更多
关键词 Major project Risk assessment Cumulative prospect theory
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基于密度泛函理论的S掺杂碳载体负载Pt催化剂对氧还原反应的影响
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作者 叶蔚甄 任强 +1 位作者 王春璐 曲亚坤 《石油学报(石油加工)》 EI CAS CSCD 北大核心 2024年第4期931-941,共11页
采用密度泛函方法对比研究了Pt/C催化剂中碳载体掺S前后对氧还原反应(ORR)的影响。从电荷分布、态密度及d带中心等性质出发,分析了金属-载体间相互作用,研究了ORR各物种在催化剂上的吸附并计算了ORR过电势。结果表明:S掺杂使得碳载体表... 采用密度泛函方法对比研究了Pt/C催化剂中碳载体掺S前后对氧还原反应(ORR)的影响。从电荷分布、态密度及d带中心等性质出发,分析了金属-载体间相互作用,研究了ORR各物种在催化剂上的吸附并计算了ORR过电势。结果表明:S掺杂使得碳载体表面发生了电子转移,S上的电子转移到邻近的C原子上,负载Pt纳米颗粒后,Pt金属上的电子转移给了碳载体;Pt在S掺杂碳载体上的吸附更强,形成了Pt—C键和Pt—S键,Pt纳米颗粒的分散度和稳定性得到了提升;掺S使得催化剂d带中心下降,对ORR各中间体的吸附减弱,ORR过电势降低,表明掺S能提高催化剂的催化活性。 展开更多
关键词 S掺杂 pt基催化剂 氧还原反应 密度泛函理论 态密度 d带中心 过电势
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Pt-HfSe_(2)检测SF_(6)分解组分的传感机理研究
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作者 胡雄雄 邹铃尉 +1 位作者 张小林 崔豪 《湖南电力》 2024年第3期48-54,共7页
通过检测SF_(6)分解组分可有效评估电气设备设备运行状态,进而保障设备的安全稳定运行。基于第一性原理提出Pt掺杂HfSe_(2)(Pt-HfSe_(2))检测SO_(2)和SOF_(2),研究Pt-HfSe_(2)对两种气体组分的吸附和传感机理,探究其作为电阻型气体传感... 通过检测SF_(6)分解组分可有效评估电气设备设备运行状态,进而保障设备的安全稳定运行。基于第一性原理提出Pt掺杂HfSe_(2)(Pt-HfSe_(2))检测SO_(2)和SOF_(2),研究Pt-HfSe_(2)对两种气体组分的吸附和传感机理,探究其作为电阻型气体传感器评估SF_(6)电气设备运行状态的应用潜力。结果表明,Pt-HfSe_(2)对SO_(2)的吸附性能强于对SOF_(2)的,同时,两种气体在Pt-HfSe_(2)表面具有较好的脱吸附性能,能够保证该传感材料的重复使用。Pt-HfSe_(2)具备开发为新型SO_(2)和SOF_(2)气体传感器件的条件,可用于评估SF_(6)电气设备的运行状态,为研究HfSe_(2)基气体传感器提供了理论支持,为新型纳米传感器件应用于电力设备故障诊断提供新思路。 展开更多
关键词 pt-HfSe_(2) 第一性原理 气敏传感机理 SF_(6)分解组分
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基于PT-MA理论的销售商再制品价格欺骗行为演化博弈分析
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作者 杨明歌 杨卓 梁小珍 《运筹与管理》 CSCD 北大核心 2023年第11期94-101,I0042-I0044,共11页
数字经济在推动再制造产业快速发展的同时,也带来大量的数据滥用和侵权行为。例如,销售商为获取更多利益,利用数字经济虚拟性和隐蔽性的特点,进行再制品价格欺骗。这种行为不仅严重损害消费者的权益,还破坏再制品市场的公平性。本文研... 数字经济在推动再制造产业快速发展的同时,也带来大量的数据滥用和侵权行为。例如,销售商为获取更多利益,利用数字经济虚拟性和隐蔽性的特点,进行再制品价格欺骗。这种行为不仅严重损害消费者的权益,还破坏再制品市场的公平性。本文研究闭环供应链中销售商的再制品价格欺骗行为。首先,将前景理论和心理账户(PT-MA)理论引入销售商、政府和消费者的三方博弈中,构建前景收益感知矩阵。其次,根据复制动态方程原理建立三方演化博弈模型,并通过Lyapunov第一法求解系统的演化稳定策略。最后,通过数值仿真研究销售商、政府和消费者的策略演化路径的影响因素。研究表明:i)降低效价参照点或成本参照点均可促使销售商选择不伪装;ii)提高风险偏好系数可促使系统演化至“销售商不伪装,政府严格监管,消费者购买”的稳定状态;iii)提高损失规避程度可促使销售商选择不伪装且政府选择严格监管。 展开更多
关键词 前景理论 心理账户理论 前景收益感知矩阵 价值感知 复制动态方程
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Theory, Practice and Prospection of Si Fertilizer 被引量:1
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作者 弗拉基米尔.马基琴科夫 魏晓 +1 位作者 刘代平 埃琳娜.伯查妮科娃 《Agricultural Science & Technology》 CAS 2013年第3期498-502,506,共6页
This paper summarizes the theory of the chemical and physical properties of Si, soil classification for Si soil test and Si fertilizer types, effect of Si fertilizer on plant and soil etc., and proves that Si fertiliz... This paper summarizes the theory of the chemical and physical properties of Si, soil classification for Si soil test and Si fertilizer types, effect of Si fertilizer on plant and soil etc., and proves that Si fertilizer can increase the P nutrition, yield and quality, resistance to any biotic and abiotic stress ability, reduce the toxici- ty of heavy metals of plants and improve the water fertilizer retention of soil by practice; also points out that the best source for Si fertilizers is natural rich Si ma- terials. At last, it gives the prospection about the application of Si fertilizer in the sustainable and organic agriculture. 展开更多
关键词 Si fertilizer theory PRACTICE prospectION
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Robust user equilibrium model based on cumulative prospect theory under distribution-free travel time 被引量:3
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作者 王伟 孙会君 吴建军 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第2期761-770,共10页
The assumption widely used in the user equilibrium model for stochastic network was that the probability distributions of the travel time were known explicitly by travelers. However, this distribution may be unavailab... The assumption widely used in the user equilibrium model for stochastic network was that the probability distributions of the travel time were known explicitly by travelers. However, this distribution may be unavailable in reality. By relaxing the restrictive assumption, a robust user equilibrium model based on cumulative prospect theory under distribution-free travel time was presented. In the absence of the cumulative distribution function of the travel time, the exact cumulative prospect value(CPV) for each route cannot be obtained. However, the upper and lower bounds on the CPV can be calculated by probability inequalities.Travelers were assumed to choose the routes with the best worst-case CPVs. The proposed model was formulated as a variational inequality problem and solved via a heuristic solution algorithm. A numerical example was also provided to illustrate the application of the proposed model and the efficiency of the solution algorithm. 展开更多
关键词 user equilibrium cumulative prospect theory distribution-free travel time variational inequality
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Traffic assignment problem under tradable credit scheme in a bi-modal stochastic transportation network: A cumulative prospect theory approach 被引量:2
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作者 HAN Fei ZHAO Xiang-mo CHENG Lin 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第1期180-197,共18页
The traffic equilibrium assignment problem under tradable credit scheme(TCS) in a bi-modal stochastic transportation network is investigated in this paper. To describe traveler’s risk-taking behaviors under uncertain... The traffic equilibrium assignment problem under tradable credit scheme(TCS) in a bi-modal stochastic transportation network is investigated in this paper. To describe traveler’s risk-taking behaviors under uncertainty, the cumulative prospect theory(CPT) is adopted. Travelers are assumed to choose the paths with the minimum perceived generalized path costs, consisting of time prospect value(PV) and monetary cost. At equilibrium with a given TCS, the endogenous reference points and credit price remain constant, and are consistent with the equilibrium flow pattern and the corresponding travel time distributions of road sub-network. To describe such an equilibrium state, the CPT-based stochastic user equilibrium(SUE) conditions can be formulated under TCS. An equivalent variational inequality(VI) model embedding a parameterized fixed point(FP) model is then established, with its properties analyzed theoretically. A heuristic solution algorithm is developed to solve the model, which contains two-layer iterations. The outer iteration is a bisection-based contraction method to find the equilibrium credit price, and the inner iteration is essentially the method of successive averages(MSA) to determine the corresponding CPT-based SUE network flow pattern. Numerical experiments are provided to validate the model and algorithm. 展开更多
关键词 tradable credit scheme cumulative prospect theory endogenous reference points generalized path costs stochastic user equilibrium variational inequality model heuristic solution algorithm
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Oderly accumulation theory of shale system petroleum resource and its prospecting significance-A case study of Chang 7 Member of Yanchang Formation in Ordos Basin 被引量:5
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作者 Cui Jingwei Zhu Rukai +1 位作者 Li Shixiang Zhang Zhongyi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期265-266,共2页
1 Introduction Shale formations bear abundant mineral resource and*unconventional petroleum resource,and the unconventional petroleum resource that contain in the shale formation should be integrated and researched.
关键词 In Oderly accumulation theory of shale system petroleum resource and its prospecting significance-A case study of Chang 7 Member of Yanchang Formation in Ordos Basin
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Pt-C_(3)N_(4)/BiOCl S型异质结应用于光催化CO_(2)还原的理论计算研究 被引量:3
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作者 罗铖 龙庆 +2 位作者 程蓓 朱必成 王临曦 《物理化学学报》 SCIE CAS CSCD 北大核心 2023年第6期135-144,共10页
光催化CO_(2)还原制备可再生的碳氢燃料为缓解温室效应、解决能源短缺问题提供了一个可行的办法。然而,单一组分光催化剂的CO_(2)还原活性非常低。一是因为光生载流子的快速复合导致光子效率很低。二是因为CO_(2)的活化需要较高的能垒... 光催化CO_(2)还原制备可再生的碳氢燃料为缓解温室效应、解决能源短缺问题提供了一个可行的办法。然而,单一组分光催化剂的CO_(2)还原活性非常低。一是因为光生载流子的快速复合导致光子效率很低。二是因为CO_(2)的活化需要较高的能垒。对此,研究人员作出了许多改进以提高CO_(2)还原性能。例如,发展S型异质结可以增强载流子的分离和光催化剂的氧化还原能力,引入金属单原子助催化剂可以优化反应热力学。因此,协同利用S型异质结和金属单原子修饰将能同时促进载流子的转移和CO_(2)还原反应过程。本文构建了由单原子Pt负载的g-C_(3)N_(4)和BiOCl组成的Pt-C_(3)N_(4)/BiOCl异质结模型。用密度泛函理论计算研究了其光催化性能,包括几何结构和电子性质的探索、CO_(2)转化过程的模拟。差分电荷密度结果表明g-C_(3)N_(4)中的电子转移至BiOCl,这是由于g-C_(3)N_(4)的费米能级比BiOCl的费米能级高。由此在g-C_(3)N_(4)/BiOCl异质结的界面处形成了由g-C_(3)N_(4)指向BiOCl的内建电场。在光照下,g-C_(3)N_(4)/BiOCl复合物中载流子的转移路径符合S型机制。具体而言,BiOCl导带的光生电子与g-C_(3)N_(4)价带的光生空穴复合,而g-C_(3)N_(4)导带的电子与BiOCl价带的空穴得以保留。在g-C_(3)N_(4)的空隙中添加Pt原子后,g-C_(3)N_(4)的功函数减小,由此增大了g-C_(3)N_(4)和BiOCl的费米能级差异。结果,有更多的电子从Pt-C_(3)N_(4)转移至BiOCl,内建电场的强度增大。这有利于Pt-C_(3)N_(4)/BiOCl S型异质结的电荷转移。此外,反应自由能计算结果表明,g-C_(3)N_(4)/BiOCl异质结上CO_(2)还原反应的限速步骤是CO_(2)氢化生成COOH,其能垒为1.13 eV。Pt原子修饰后,限速步骤变为CO氢化生成HCO,其能垒为0.71 eV。这些结果表明Pt单原子的引入能够增强界面电场、降低能垒,从而提高CO_(2)还原活性。本工作为构建金属原子修饰的S型异质结光催化剂以实现高效的CO_(2)还原提供了理论指导。 展开更多
关键词 S型异质结 密度泛函理论 光催化CO_(2)还原 单原子pt 氮化碳 BiOCl 内建电场
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A prospect theory-based methodfor linguistic decision making under risk
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作者 Liu Shuli Liu Xinwang 《Journal of Southeast University(English Edition)》 EI CAS 2017年第3期370-376,共7页
Based on the prospect theory, a novel linguisticdecision method under risk is proposed. First, the alternativesunder each risk state are rated using linguistic terms, and' thelinguistic decision matrix is constructed... Based on the prospect theory, a novel linguisticdecision method under risk is proposed. First, the alternativesunder each risk state are rated using linguistic terms, and' thelinguistic decision matrix is constructed. Secondly, thelinguistic terms are transformed into triangular fuzzy numbers,so that the linguistic evaluations can be changed into numericalforms. Thirdly, with the aid of the prospect theory, theprobability weight functions and the linguistic value functionscan be computed, based on which the prospective values of thealternatives are obtained. Finally, the alternatives are rankedwith respect to the prospective values combined of probabilityweight and linguistic value functions. Thus, the optimalchoice is made. The decision process takes the psychologicalpreferences of the decision maker into consideration. Thepracticality of the proposed method is illustrated through anapplication on stock selection problems. 展开更多
关键词 DECISION MAKING under RISK LINGUISTIC evaluation prospect theory STOCK selection
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基于MA-CPT模型的出行方式选择模型优化 被引量:1
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作者 黄奕慧 杨飞 +1 位作者 张栋 曾优美 《西南交通大学学报》 EI CSCD 北大核心 2023年第2期367-372,共6页
为提高累积前景理论在出行方式选择建模应用中的准确性,考虑个体对于时间与费用货币态度的不同,优化原始累积前景理论(cumulative prospect theory,CPT)模型的时间值函数和时间权重函数.首先,针对时间压力下出行方式偏好发生转变的现象... 为提高累积前景理论在出行方式选择建模应用中的准确性,考虑个体对于时间与费用货币态度的不同,优化原始累积前景理论(cumulative prospect theory,CPT)模型的时间值函数和时间权重函数.首先,针对时间压力下出行方式偏好发生转变的现象,将出行方式分为刚性出行和弹性出行,改进刚性出行情景下的时间值函数形式,并根据出行时间特性求出时间权重函数中吸引力参数的取值范围,构建MA-CPT (mental accountingcumulative prospect theory)模型;其次,根据实证数据标定时间权重函数中辨别力参数和吸引力参数的取值;最后,标定MA-CPT模型结果并检验其拟合优度,对比MA-CPT模型和CPT模型的命中率.实证分析结果表明:刚性出行和单行出行场景下,时间权重函数的吸引力参数值均大于1.00;MA-CPT模型在刚性出行和弹性出行情境下的拟合优度分别为0.17和0.18;相比于CPT模型,MA-CPT模型在弹性出行和刚性出行情景下的命中率分别提高了12.2%和19.8%. 展开更多
关键词 城市交通 出行方式选择模型 累积前景理论 心理账户理论 时间权重函数
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Prospect Theory Based Hesitant Fuzzy Multi-Criteria Decision Making for Low Sulphur Fuel of Maritime Transportation
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作者 Changli Lu Ming Zhao +1 位作者 Imran Khan Peerapong Uthansakul 《Computers, Materials & Continua》 SCIE EI 2021年第2期1511-1528,共18页
The environmental impact of maritime transport has now become a relevant issue in sustainable policy formulation and has attracted increasing interest from academia.For the sustainable development of maritime transpor... The environmental impact of maritime transport has now become a relevant issue in sustainable policy formulation and has attracted increasing interest from academia.For the sustainable development of maritime transport,International Maritime Organization stipulates that the sulfur content of ship emissions will reach 0.5 from 2020.With the approaching of the stipulated implementation date,shipowners need to adopt scientific methods to make decision on low sulfur fuel.In this study,we applied a prospect theory based hesitant fuzzy multi-criteria decision-making model to obtain the optimal decision of low Sulphur marine fuel.For this purpose,the hesitant fuzzy decision matrix is established to collect expert opinions,the maximizing deviation method is adopted to determine criteria weights.According to calculate the Euclidean distance from the reference points,we obtain the comprehensive prospect values of alternatives.Lastly,a case study is carried out to illustrate the significance and effectiveness of the proposed methodology.The innovation of this study is that it is the first-time adopting prospect theory and hesitate fuzzy sets to multi-criteria decision making for low Sulphur marine fuel,which provides an effective decision model for shipping companies under Low Sulphur regulations,and can also be extended to other industries. 展开更多
关键词 Maritime transport prospect theory hesitant fuzzy sets multi-criteria decision making maximizing deviation method euclidean distance
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Adsorption of HCN on Ni/Pt(111)Bimetallic Surfaces Investigated with Density Functional Theory Method
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作者 黄攀 史晓琪 +3 位作者 冯晓宁 刘建治 李奕 章永凡 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第10期1491-1500,共10页
We applied periodic density-functional theory to investigate the adsorption of HCN on x Ni@Pt(111) bimetallic surfaces(x = 1~4). The results have been compared with those obtained on pure Ni(111) and Pt(111) s... We applied periodic density-functional theory to investigate the adsorption of HCN on x Ni@Pt(111) bimetallic surfaces(x = 1~4). The results have been compared with those obtained on pure Ni(111) and Pt(111) surfaces. For all bimetallic surfaces,HCN is preferentially tilted with the CN bond parallel to the surface,and adsorption energies increase with an increasing number of layer Ni atoms on the surface. The adsorption energies of HCN on all bimetallic surfaces are larger than that on the Pt(111) surface,whereas the adsorption energies of HCN on 3Ni@Pt(111) and 4Ni@Pt(111) are larger than that on the Ni(111) surface,indicating that the introduction of Ni to the Pt catalyst could increase the activity of bimetallic catalyst in the hydrogenation reaction for nitriles. Larger adsorption energy of HCN leads to a longer C–N bond length and a smaller CN vibrational frequency. The analysis of Bader charge and vibrational frequencies showed obvious weakening of the adsorbed C–N bond and an indication of sp2 hybridization of both carbon and nitrogen atoms. 展开更多
关键词 hydrogen cyanide Ni/pt(111) bimetallic surfaces density functional theory
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Evaluation of the Effect of China’s Health Care Reform Based on Prospect Theory
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作者 Guan Yueyue Huang Zhe 《Asian Journal of Social Pharmacy》 2022年第1期1-10,共10页
Objective To evaluate the effect of health care reform policy in China comprehensively and provide suggestions for its further implementation.Methods Data on the effect of health care reform were obtained from“China ... Objective To evaluate the effect of health care reform policy in China comprehensively and provide suggestions for its further implementation.Methods Data on the effect of health care reform were obtained from“China Health Statistics Yearbook”and National Bureau of Statistics of China and the indicators were selected by corrected item total correlation(CITC)and Cronbach’sαreliability coefficient.Then,the selected indicators were calculated through the prospect theory model.Meanwhile,the gray relation analysis method was introduced to enlarge the differences between the advantages and disadvantages to make the comprehensive evaluation result more obvious.Results and Conclusion The implementation of China’s health care reform has a significant impact on China’s medical and health system.However,the effect of the policy will become less with the increase of the total amount.An effective management can ensure that the policy continues to play its role. 展开更多
关键词 new health reform prospect theory policy evaluation
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中国锂矿的多旋回深循环内外生一体化成矿理论及其找矿应用 被引量:1
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作者 王登红 代鸿章 +9 位作者 刘善宝 王成辉 李建康 李鹏 陈郑辉 于扬 秦锦华 孙艳 娄德波 姚佛军 《地质学报》 EI CAS CSCD 北大核心 2024年第3期889-897,共9页
中国锂资源的分布具有卤水型与硬岩型相伴相随、若即若离的特点。“多旋回深循环内外生一体化”成锂理论,在多年三稀金属矿产找矿实践和理论研究的基础上不断丰富完善。中国锂矿的形成与“多旋回”构造运动密切相关,从前寒武纪到新生代... 中国锂资源的分布具有卤水型与硬岩型相伴相随、若即若离的特点。“多旋回深循环内外生一体化”成锂理论,在多年三稀金属矿产找矿实践和理论研究的基础上不断丰富完善。中国锂矿的形成与“多旋回”构造运动密切相关,从前寒武纪到新生代均有成矿潜力,可构成一个完整的多旋回成矿谱系。锂的“深循环”,一是锂深度参与成岩成矿的物质循环;二是需要一个“圈闭”的构造背景将锂“捕获”以避免其过度分散,锂从开始加入到岩浆与最终定位的深度之差,是硬岩型锂矿成矿的关键之一,压差越大越有利于伟晶岩型锂矿的形成。大量锂矿实例显示锂的物质循环是“内外生一体化”的统一过程,高海拔地区(山上)的含锂地质体(花岗岩类甚至直接就是含锂矿床)经风化剥蚀之后,可能成为沉积型锂矿的物质来源之一;而富含锂的沉积岩经过埋藏、变质、深熔也可以形成含锂的岩浆岩、伟晶岩。我国西部塔里木盆地、四川盆地、扎布耶盆地及东部的江汉盆地、吉泰盆地、周田盆地等大小不一的盆地均含锂,而其周边造山带中也不同程度发育硬岩型锂矿,这就为区域找矿指明了方向。“多旋回深循环内外生一体化”成锂理论是三稀矿产成矿理论的重要组成部分,为我国锂矿找矿工作提供了指导和借鉴,在甲基卡、可尔因、阿尔金、幕阜山等锂矿矿集区的找矿实践中发挥了积极作用。 展开更多
关键词 锂矿 构造运动 “多旋回深循环内外生一体化”成矿理论 找矿应用
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Pt_(n)Rh_(38-n)团簇电子结构及吸附性的密度泛函理论研究
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作者 梁晓庆 陆林璐 《台州学院学报》 2023年第3期1-9,共9页
铂、铑及其合金团簇因其催化活性受到广泛关注。为了深入了解Pt-Rh纳米团簇的结构和电子特性,使用密度泛函理论计算并确定了不同组分Pt_(n)Rh_(38-n)团簇的最低能量结构。同时,在对其合金团簇结构研究后发现:Pt原子倾向于占据团簇表面,... 铂、铑及其合金团簇因其催化活性受到广泛关注。为了深入了解Pt-Rh纳米团簇的结构和电子特性,使用密度泛函理论计算并确定了不同组分Pt_(n)Rh_(38-n)团簇的最低能量结构。同时,在对其合金团簇结构研究后发现:Pt原子倾向于占据团簇表面,而Rh原子倾向于占据团簇内部,从而形成了Rh(核)-Pt(壳)结构。在此基础上,进一步研究了团簇对CO分子的吸附性,发现CO更倾向于吸附在Pt_(n)Rh_(38-n)团簇表面的Rh原子上,根据电子态密度分析,其原因是费米能级附近的d电子贡献主要来自Rh原子。以上研究结果对于Pt-Rh中等尺寸合金团簇的结构形成、电子性质以及CO分子的吸附性能有了更加全面的认识,为双金属团簇的研究提供了理论依据。 展开更多
关键词 铂铑团簇 密度泛函理论 电子结构 吸附性
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