关键词： 渔业自反馈模型   密度   平衡点   稳定性  

摘要： 文章在渔业自反馈模型的基础上建立了家禽类种群的数学经济模型,分析了家禽类种群密度对经营者经济利益的影响,并且对其平衡点的稳定性进行系统的研究.

关键词： Love   Intertemporal choice   Effort   Well-being   Behavioral  

摘要： It is apparent that love influences people's choices, yet little work in economics has focused on how love develops or why it matters for resource allocation decisions. Here, we present a simple dynamic model of how love develops and evolves, recognizing our parsimonious model will not capture all the nuances associated with such a complex topic. Nonetheless, our love dynamic, motivated by a few intuitive assumptions, can explain many observed facts, like why stable love relationships can develop but also why blossoming relationships can unexpectedly take a turn and ultimately dissolve. We embed our love dynamic in an intertemporal optimization problem and derive the optimal path for effort put toward a love relationship when it can also produce material consumption. The optimal path offers an explanation for why "taking the other for granted" may be rational. (C) 2019 Elsevier B.V. All rights reserved.

关键词： 体形系数   能耗模拟   保温系统   经济模型   最优厚度  

摘要： 建筑体形系数是节能设计指标参数之一,但目前关于其对外保温最优厚度的影响研究较少.本文通过DeST能耗模拟,建立外保温最优厚度数学模型,在保持建筑层高H和周长L不变情况下,探究体形系数对最优厚度的影响规律.研究结果表明:采取节能保温措施后,单位建筑面积能耗随着体形系数的减小而增大;建筑体形系数与生命周期总费用成正相关,与外保温最优厚度成负相关;从绝对经济增量角度考虑,体形系数对生命周期内总费用影响的实际参考价值大于对最优厚度的影响.

关键词： 线性代数   线性经济模型   课程内容体系  

摘要： 针对目前线性代数课程教学的特点,基于线性经济模型问题,探讨线性代数课程理论内容主线和逻辑结构,研究以线性方程组为主线,学科内应用和经管类专业应用为驱动的专业背景与数学理论恰当融合的教学内容体系,使得课程内容适应应用型教学需求,为应用型人才培养服务.

关键词： 产业结构合理化   空间溢出效应   农村贫困   减贫   空间计量经济模型   产业结构优化升级   空间异质性   空间相关性  

摘要： 在对我国省域产业结构合理化与高度化水平进行测度的基础上,构建空间计量经济模型,设置邻接权重、地理权重和经济权重三种空间关联模式,从空间维度实证检验产业结构优化升级对农村贫困影响的直接效应与溢出效应。研究发现:我国省域农村贫困率具有显著的空间相关性和空间异质性,在空间分布上呈现“高一高”与“低一低”集聚的特征;产业结构的合理化不仅能促进本地区农村减贫,还可以通过空间溢出效应促进邻近地区农村减贫;产业结构的高度化也有助于本地区和相邻地区的农村减贫。

关键词： Altruistic giving   Bystander effect   Congestible altruism   Dictator game   Inequity-aversion model  

摘要： The extent of altruistic giving is influenced by the numbers of givers and recipients available in a group. Two independent lines of research have addressed the effect. On the one hand, research on the bystander effect shows that a person gives less when givers outnumber recipients than if they are equal in number. On the other, studies of congestible altruism have found that a person gives more when recipients outnumber givers than if they are equal in size. An interesting question is whether giving decreases at a different rate when givers outnumber recipients than it increases the other way around. Answering the question helps illuminate whether the two effects of collective giving, which the literature has discussed separately, are governed by the same rule. We conducted a multi-person dictator game experiment to investigate people's giving behavior in different group sizes of givers and recipients. We found that giving decreases more rapidly when givers outnumber recipients than it increases the other way around. A behavioral economics model is proposed to show how people's belief about the selfishness of other givers can account for the asymmetry of the two effects.

关键词： War   Trade   Taxes   Debt   Multipliers   Welfare  

摘要： This paper proposes a straight model-based analysis of historical war episodes. We analyze the effects of world wars on the macroeconomic dynamics in the US, France, Germany, and the UK, by means of an estimated open-economy model where war episodes are modeled as an additional source of observed shocks. The model allows war episodes to affect the economy through lower capital depreciation, partial default on public debt, a military draft, changes in household preferences, and spillovers on other shocks (productivity, investment, trade, policy variables). In the US, the bulk of fluctuations during war episodes can be mainly explained by the rise in government spending, and the war shock plays a minor role. In other countries, the war shock is an essential driver of fluctuations. We also discuss the size and state-dependence of public spending multipliers, and produce a counterfactual exercise to quantify the welfare losses from war episodes. (C) 2019 Elsevier B.V. All rights reserved.

关键词： Offset-free control   Economic MPC   Dynamic target optimization   Stability  

摘要： The optimization and control of large-scale industrial systems are typically based on hierarchical structures. The real-time optimizer (RTO) solves a steady-state setpoint optimal problem in long time-scale, based on a rigorous nonlinear model. The down-layer advanced controller is designed to achieve set point tracking based on a linear model to get efficient computation. This paradigm on the one hand lacks consideration about dynamic economic performance, on the other hand leads to the unreachable and inconsistent issues, which cause feasibility problem in the controller and the deviation of the plant operating point, i.e., offset. In this work, a linear offset-free economic model predictive controller (EMPC) is proposed for systems in the presence of model mismatch. The method constituted by a dynamic target optimization (DTO) stage and the following EMPC stage. These two stages work in a bidirectional way. The DTO stage uses the dynamic augmented model to derive a feasible trajectory with the terminal target attainable for down-layer EMPC. The EMPC optimizes the dynamic economic performance in the presence of a contractive energy-like constraint related to the feasible trajectory. Recursive feasibility, input-to-state stability (ISS) and offset-free property are guaranteed. The proposed method is applied to a fluid catalytic cracking (FCC) process. The numerical results demonstrate the effectiveness of the proposed offset-free EMPC for improving the overall economic performance and achieving stability and offset-free property in process control. (C) 2019 Elsevier Ltd. All rights reserved.

关键词： 技术经济   模型   硫酸盐浆   漂白   模拟   评价  

摘要： 评估了各类技术经济模型研究成果,描述了其发展及在不同漂白浆生产中的应用与优点.20世纪80年代末90年代初,研究发现漂白浆厂向水域排放大量的氯化有机物,这导致了漂白化学品的广泛研究与开发,以淘汰漂白过程中氯和次氯酸盐漂白化学品.随着时间的推移,100%的二氧化氯无元素氯(ECF)漂白替代氯成为工业标准,研究重点转向了ECF漂白流程化学品的优化.脱木素模型与漂白模型的开发与完善已应用于漂白浆厂化学品性能模拟优化;计算机能力的提高、封装电子表格的应用与模拟程序一起引导了漂白浆厂详细物料与能源平衡模型的发展.这些模拟已应用于使漂白与生产成本的最小化、协助资本支出规范评价与减少结垢生产条件的预测,并被广泛应用于新建与改造漂白浆厂环保指标的预测.

关键词： 保护区   Gompertz增长   两斑块   最优捕捞路径  

摘要： 研究了同一鱼类种群同时分布于保护区斑块和非保护区斑块,且鱼群密度服从Gompertz增长的生物经济系统.首先,证明了系统内存在唯一的非平凡奇点并且局部稳定,运用Bendixson-Dulac定理得到该奇点的全局稳定性;然后,通过Pontryagin最大值原理获得该鱼类种群的最优捕捞路径;最后,通过数值模拟来说明部分结论.