关键词： Deforestation   Global environmental change  

摘要： Tropical deforestation has been one of the most significant global environmental changes of recent decades and has spurred a substantial academic literature. Despite this, the empirical literature provides inconsistent evidence on the role of basic economic determinants of deforestation such as income and population. The authors suggest that one explanation for this inconsistency is a tendency to use incomplete or incorrect dynamic regression specifications. They derive three plausible dynamic empirical model specifications and compare their performance both with each other and with an ad hoc model typical of those used in the literature. Statistical tests support the use of more completely specified models which allow for dynamic adjustment of forest cover.

关键词： 桥梁   加固   重建   经济性   经济模型   方案优选  

摘要： 在桥梁改造基本原则的基础上,从经济性角度出发,考虑桥梁生命周期内发生的所有费用,引入加固与重建两种方案的经济模型,以既有桥梁为研究对象,对加固和重建两种方案的平均年费用进行分析、比较,并优选了最佳方案,并对桥梁生命周期进行了预测,为桥梁改造方式提供了理论基础。

关键词： 产业经济   职业教育   供需失衡   结构性矛盾   经济模型  

摘要： 受多种因素影响,职业教育供需问题日益突出,很多专家对此开展了大量研究,比较发现,已有研究成果都是基于现实的供需表象进行分析,思辨性强而论据不足,难免影响分析的质量,本文创新性的提出基于经济学模型开展职教供需问题探索,指出职业教育产生供需失衡的本质原因是技术技能型人才给产业经济创造的总效用未能满足其人资需求预算,同时从供给弹性的角度,分析了职业教育供需失衡后的反应路径,并初步探讨了产业经济对技术技能型人才的需求的计算模型,对深化职业教育供给侧结构性改革有一定的指导意义。

关键词： 需求侧管理   电—热混合能源系统   经济模型   储能装置   优化调控  

摘要： 我国"十三五"节能减排工作以多能源合利用及需求侧管理(demand-sidemanagement,DSM)作为我国提高终端能效重点推广的用能模式。未来的热-电混合能源系统及需求侧管理涵盖多种能源资源,涉及多元主体,受多种因素的影响。为了协调能源系统的多种影响因素,对热一电混合能源系统的基础模型进行研究,提出了需求侧管理优化调控的经济模型。考虑各时段储能装置的状态,对关键影响因素进行详细建模。通过算例验证了模型的优越性以及对不同储能情景下影响因素变动的优化调控,为进一步挖掘我国电力需求侧资源,优化更复杂的热—电混合能源系统提供借鉴。

关键词： 风光互补供暖系统   热平衡模型   经济模型   遗传算法   经济分析  

摘要： 针对秦皇岛地区风力资源丰富、太阳辐射量充足的特点,设计了一种风电-太阳能集热-市电联合供暖系统,并建立了热平衡模型和经济模型。设置系统的寿命周期分别为10,15,20a,从投资的角度利用遗传算法对经济模型进行了全局优化。与传统燃煤供暖方式对比结果显示,该系统在15a和20a的运行周期内比传统供暖方式具有更好的经济效益和社会效益,在农村地区具有广阔的应用前景。

关键词： Cobb-Douglas function   maximum-principle boundary-value problem   numerical experiments   optimal control   Pontryagin maximum principle   program-form control   singular regimes  

摘要： We investigate the resource allocation problem in a two-sector economic model with a Cobb-Douglas production function with different depreciation rates. The problem is considered on a finite time horizon with an integral type functional. Optimality of the extremum solution constructed by the Pontryagin maximum principle is established. When the planning horizon is sufficiently long, the optimal control has two or three switching points, contains one singular section, and vanishes on the terminal section. A transitional “calibration” regime exists between the singular section, where the motion is along a singular ray, and the terminal section. The solution of the maximum-principle boundary-value problem is presented in explicit form, accompanied by graphs based on numerical results. © 2017, Springer Science+Business Media, LLC.

关键词： Security cost-benefit analysis   Security cost-effectiveness analysis   Physical security measures   Security decision-making   Chemical industry   Environmental accident  

摘要： Several recent events raised the attention toward possible major accidents triggered by external acts of interference in industrial facilities. In particular, a growing concern is present with respect to the intentional release of dangerous substances resulting in environmental and eco-terroristic attacks. Therefore, optimal selection and allocation of preventive security measures is becoming more important for decision-makers. Despite the existence of economic models supporting the decision-making process, their applications within the chemical industry Security context are relatively limited. This study describes a specific model for economic analysis and selection of physical security measures, with respect to potential environmental and eco-terroristic attacks in chemical facilities. An example of application to a relevant case study is presented to show the model capabilities. Site-specific analysis of the baseline physical security system performance allows comparing the costs of different security upgrades with the benefits related to either prospective or retrospective losses, meanwhile accounting the uncertainties related to the threat probability. Selection of the most profitable security measures within budget constraints and definition of economic indicators are the main outputs of the model, in order to support decision-making processes for allocation of security barriers. (C) 2017 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.

关键词： R10   R13   O18  

摘要： Urban agglomeration has attracted attentions of urban planners, economists, and policymakers. For the sake of urban agglomeration simulation, this paper attempts to develop a computable urban economic (CUE) model incorporated with economies of scale, through the approach of new economic geography. It is assumed that each firm produces a product variant in a monopolistic competition market, and the number of firms is explicit and determined endogenously. The Dixit-Stiglitz type utility function with product variety is adopted into the households' behavior to reflect consumers' preference for variety. On the other hand, internal increasing returns to scale and fixed cost are introduced in firms' behavior to extend the model with economies of scale. The model's parameter estimations and calibration are conducted on the basis of empirical data from several approved sources for Changzhou in 2008. Numerical computations are implemented by employing the extended CUE model incorporated with economies of scale to explain and examine how the urban agglomeration comes into being. Simulation results show that the extended model incorporated with economies of scale is able to commendably represent the urban agglomeration mechanism, providing a promising simulation tool for urban planning and policymaking.

关键词： 博弈论   计量经济模型   经济学   经济发展  

摘要： 博弈计量经济模型是数学中的博弈论和经济学中的计量经济模型相互结合的产物,他综合了博弈论和计量经济模型的优势,成为当前分析经济问题的最有效的方法,使得经济问题的分析和解决有了更加高效的分析手段。本文在前人研究的基础上从静态博弈计量经济模型、静态博弈计量经济模型等两个方面进行了论述,希望对解决我国的经济问题提供强有力的理论保障。

关键词： 天然表面活性剂   Designer   成本分析   经济评估   运营成本   生产成本   经济模型   软件开发  

摘要： 11成本分析在建设和运作工厂之前,工艺的设计和经济评估是很重要的,这需要结合工程学的知识[66]。总体成本分析包括评估资本和运营开支。基于由Superpro Designer模拟软件开发的工艺经济模型,由葡萄糖和高油酸的葵花籽油生产907 00 t的槐糖脂的年运营成本为2.68亿美元,单位生产成本每千克2.95美元。