配电网中感应雷电波传变特性的研究

本文从理论上分析了感应雷电波从架空配电线到变压器低压端的传输特性。基于Agrawal模型对感应雷击电磁脉冲作用下配电线路-变压器系统的过电压进行数值模拟,得到变压器接入对线路末端感应电压影响的仿真结果;采用传输线等效电路模型和戴维南等效定理,将雷击感应电压作用到配电变压器上,仿真计算了雷击浪涌传变到变压器低压侧的特性。     

对"项目投资关联优化定理"的质疑与修正

文献[9]建立了项目投资关联优化模型,提出了相互等价的定理3和定理6,本文证明了定理3和定理6存在无法判别方案优劣的区间,杨氏定理难以成立;利用文献[9]中的案例进行的实证分析,证明纯经济效益最大化才是互斥方案选优决策的科学准则。     

Optimal investment and consumption under a continuous-time cointegration model with exponential utility

In this paper, we study the effects of cointegration on optimal investment and consumption strategies for an investor with exponential utility. A Hamilton-Jacobi-Bellman (HJB) equation is derived first and then solved analytically. Both the optimal investment and consumption strategies are expressed in closed form. A verification theorem is also established to demonstrate that the solution of the HJB equation is indeed the solution of the original optimization problem under an integrability condition. In addition, a simple and sufficient condition is proposed to ensure that the integrability condition is satisfied. Financially, the optimal investment and consumption strategies are decomposed into two parts: the myopic part and the hedging demand caused by cointegration. Discussions on the hedging demand are carried out first, based on analytical formulae. Then numerical results show that ignoring the information about cointegration results in a utility loss.     

Moral economics

An adequate normative economics – one that is consistent with recent developments in our discipline (and in philosophy and psychology) and that resonates with widely held moral intuitions – will have to address the following challenges. First, utility cannot be both the basis of our predictions of economic behaviour and the evaluation of the outcomes of this behaviour. Second, we need to conceive of individual well-being and other desiderata in ways that are interpersonally comparable and that go beyond efficiency and fairness. Third, the representation of the economy as a ‘morality-free zone’ (requiring that contracts, including employment contracts, are complete) must give way to a recognition of the unaccountable exercise of power by private actors, even in a perfectly competitive equilibrium, and the way that this may violate democratic principles and limit the freedom and compromise the dignity of other actors. Fourth, the commitment to ‘liberal neutrality’ (thereby sidestepping the evaluation of preferences) and the related assumption of ‘unrestricted preferences’ in mechanism design and public policy must be abandoned, making room for a concern about the nature of our preferences and the ways that institutions shape our values.     

Limits of semistatic trading strategies

We show that pointwise limits of semistatic trading strategies in discrete time are again semistatic strategies. The analysis is carried out in full generality for a two-period model, and under a probabilistic condition for multiperiod, multistock models. Our result contrasts with a counterexample of Acciaio, Larsson, and Schachermayer, and shows that their observation is due to a failure of integrability rather than instability of the semistatic form. Mathematically, our results relate to the decomposability of functions as studied in the context of Schrödinger bridges.     

After Shleifer,who needs Mises?

The demise of socialism in Eastern Europe and the transition to a market economy in China and India marked the end of traditional comparative economics as a field. The debate between capitalism and socialism was settled. The economic calculation argument of Ludwig von Mises seemed no longer relevant. In its place, the new comparative economics (NCE) arose. The NCE focuses on the institutional differences that affect the protection of contract and property rights. The research program of Andrei Shleifer has provided numerous insights into how markets operate. This paper examines the Shleifer-inspired program in comparative economics in light of the economic calculation argument Mises made. Although the recent developments in comparative economics have extended and complemented the contributions of Mises, it has not displaced them. An account of the economic calculation problem is still missing in the new comparative economics.     

一种经济的水渠管道建设策略

本文在光的折射定理的基础上,将费马定理中光程的概念与水库管道建设费用相类比,利用光束在两点间传播时,光程最小的原理,设计了一种使包括公共管道和非公共管道在内的水库灌溉管道线路铺设费用最省的建设方案,并给出了施工方法和施工图纸。该方法通俗易懂,推广性强,可解决其他类似的工程建设中的成本最优问题。