"送猪崽"与"折现金":我国产业精准扶贫的路径分析与政策模拟研究

产业扶贫旨在将贫困户的生产活动纳入社会产业大循环,因此其一直是全世界扶贫工作的重要方式和主要目标之一.我国产业精准扶贫出现了两条新路径:一是GTP路径,即向贫困户送猪崽、鸡苗和良种等资本,直接将贫困户的生产纳入当地的产业体系;二是GSP路径,即将扶贫资金折合现金并由贫困户自己决定投资项目和选择产业.文章构建了包括贫困户和非贫困户的微观主体行为模型以及基于农村公平和效率的农村福利模型,分别研究了这两条新路径上贫困户福利和农村福利的动态演变过程,然后使用系统动力学模型进行了政策模拟,拟探索出我国产业精准扶贫的最优路径及其政策支持空间.结果显示:在第3~4年的时间内,GSP路径要优于GTP,但是超过4年,GTP路径上的贫困户福利和农村福利就会累进性超过GSP.而且,在GTP路径上的时间越长,扶贫效果就越好.在中长期,提高贫困户的技术水平,增加贫困户的初始资本额是进一步提高GTP路径上贫困户福利和农村福利水平的重要环节.文章的结论对于提高我国精准扶贫的理论自信,进一步完善我国产业精准扶贫政策体系具有一定的启示.     

基于知识权力和知识交互行为的产业集群多重知识网络演化分析

针对产业集群知识网络中客观存在但却未受关注的知识权力,结合自适应知识交互行为,采用多主体建模与仿真方法,分析知识权力的动态变化导致的产业集群多重知识网络演化。结果表明:知识权力差距及知识交互行为是促使产业集群多重知识网络形成及演化的基础,产业集群多重知识网络的演化过程具有典型的阶段性特征,其网络结构呈现出网络节点密集性与稀疏性相结合、强联结与弱联结并存、度分布高度异质性的特征。利用实际产业集群网络验证仿真结果,证明了该仿真模型的可信性。     

模拟植物生长算法在组合优化问题中的应用:研究进展

首先介绍了系统文献综述方法论与操作流程,从不同维度给出了文献分类标准;然后基于行政机构和出版来源分类标准,梳理了模拟植物生长算法(PGSA)的研究现状;接着分别针对电力系统、应急管理、设施选址、斯坦纳树、车间调度和旅行商等组合优化问题,对PGSA应用的代表性研究进行了综述,重点介绍了PGSA在若干领域的应用;最后从不同视角总结了已有研究成果,并指出PGSA解决组合优化问题的未来研究方向和具体内容。     

Transportation cost changes with statewide school district consolidation

This article studies the relationship between school district size and bus transportation costs, and estimates the change in such costs when a statewide policy of consolidation is pursued. To explore this relationship, we develop a multiple-objective model and solution procedure that combines a geographic aggregation and bus routing heuristic to generate consolidation scenarios. The heuristic was developed to explicitly consider efficiency, effectiveness, and equity objectives, and can be applied in both urban and rural states. The scenarios will generate average statewide bus transportation costs. As applied to the State of Iowa, within the legislature's proposed range of consolidation of 500-1000 students, it was found that transportation operational and capital cost increases range from 0.6 to 10.6 percent and 0.7 to 7.7 percent, respectively.     

A new energy model to capture the behavior of energy price processes

Owing to the vague fluctuation of energy prices from time to time, a new energy model, which considers both the mean-reverting behavior and the long memory property, is proposed in this paper. Since the problem of estimating parameters, in discrete time for this model, plays a central role in forecast inference, the problem of estimating the unknown parameters has been dealt with for the fractional Ornstein–Uhlenbeck process observed discretely. The asymptotic properties of these estimates are also provided. The numerical simulation results confirm the theoretical analysis and show that our method is effective. To show how to apply our approach in realistic contexts, an empirical study of energy in China, namely Daqing crude oil, is presented. The empirical results seem reasonable when compared to the real data.     

A CGE analysis of oil price change

As Chinese economy system has been depended more on the import of petroleum with the development of China, the change in the price of international oil have caused concern among economists and policy makers. This paper is to present a financial Computable General Equilibrium (CGE) model of the Chinese economy which integrates real economy and financial sectors, and to apply it to quantitatively evaluate the impacts on Chinese economy caused by international oil price changes. And the model endogenously determines the exchange rate, covering fixed, partially flexible, and completely flexile exchange rate system to consider the effect of foreign oil price changes from the point of view of macro and industrial aspects. Finally, this paper presents concluding remarks.     

Towards multi-system sociotechnical transitions: why simulate

A number of research frameworks have been developed for studying sociotechnical transitions. These are complex phenomena, particularly those involving multi-system interactions. Given these characteristics, the paper discusses the challenges in studying transitions solely through inductive inference methods. It argues that transition research has reached a point where taking the next step should include modelling and simulation as part of the standard methodological exploratory toolkit for studying the intensity, nature and timing of system interaction that lead to transitions and for producing timely and robust policy recommendations.     

国际贸易对碳减排协议的促进作用——理论框架及减排意愿的数值一般均衡情景模拟

全球碳减排谈判是具有外部性特征的多方合作博弈。文章首先构建一个单一商品无贸易多国模型,对各国的碳减排意愿进行刻画,利用相关数据对不同情景下的各国碳减排意愿进行数值一般均衡模拟;在此基础上,将国际贸易因素引入模型,重新对各国的减排意愿进行情景模拟。数值模拟结果表明:(1)经济规模越大,全球变暖持续的时间跨度越长,温度上升带来的效用损失越大,各国单方面减排意愿越强;(2)国际贸易的存在更有利于各国碳减排意愿的提高,因为各国通过减产实现减排的同时,其贸易条件得到改善,从而将减产带来的效用损失部分转嫁到其他各国;(3)当前,假借碳减排之名而抬头的新贸易保护主义不仅无法促进各国碳减排,反而将阻碍全球碳减排协议的达成。     

The effectiveness of monetary policy and output fluctuations: An asymmetric analysis

Previous studies have investigated asymmetries in the effects of monetary policy on the real economic activity by using either vector autoregressive (VAR)-based regime-switching models with smooth transition technique or Gaussian functions to parameterise the dynamic effects of structural shocks on the economy. These kinds of VAR models assume asymmetry as a short-run relationship between the series since the long-run neutrality hypothesis of money states that monetary policy can only affect productive capacity of the economy in the short run, but not in the long run. The recent theoretical literature shows that this hypothesis is not quite right. Thus, this paper examines the extent to which monetary policy has a long-run asymmetric effect on output in a number of Organisation for Economic Co-operation and Development countries by using a nonlinear hidden cointegration analysis within a likelihood-based panel framework. The findings indicate that there is a long-run relationship between the real interest rate as an indicator of monetary policy and the growth rate of real output in five countries out of nine under review. This gives support for the view that output has responded asymmetrically to the real interest rate changes. The economic implication of our results is that monetary policy affects positive and negative output fluctuations differently.     

基于Ansoft的永磁同步电机不平衡电磁力分析

与传统电机不同,永磁同步电机中永磁体产生的电磁力对电机中各个部件产生很大的影响。本文运用Ansoft仿真软件对永磁同步电动机在充磁瞬间、充磁后静态及正常运转各状态下,电机定转子偏心时,各部件所受电磁力的情况进行比较。仿真结果表明,永磁同步电机中定转子偏心对电机某些部件影响非常大。