某类高阶偏微分系统离散谱的估计

考虑某类高阶偏微分系统离散谱的估计,利用谱理论、矩阵运算、分部积分、测试函数、Ray—leigh定理和不等式估计等方法,获得了用前n个谱来估计第n＋1个谱的上界的不等式,且其估计系数与区域的几何度量无关,其结论是文献[4—5]的进一步推广．     

协同通信系统中差分调制在Rayleigh衰落信道中的误码性能分析

根据源-中继-目的节点链路的等效信噪比模型,推导了检测传送和选择检测传送两种 协议下目的节点瞬时信噪比的概率密度函数和特征函数,基于此推导了协同DMPSK调制近似 误符号率的闭合表达式。推导结果不含积分表达式,方便计算,为系统设计和功率分配提供 了理论基础。最后通过仿真验证了推导结果的正确性。     

互惠性与理性经济效应的比较性研究

在知识经济时代,行为经济学的发展动摇了传统经济理论的基础,为现代经济学的发展开辟了新的方向。作为行为经济学的基础性假设之一,互惠性偏好对经济人的理性偏好进行了强烈的挑战,从而导致互惠性企业理论对理性管理理论的冲击。互惠性理念在企业管理机制中具有一定的存在性和革命性,促进了管理行为的优化和管理机制的变革,进而有效地改进了企业的运营绩效。基于相同的企业环境,借助于组织学习与知识转移的传导机制,互惠性与理性经济效应的比较性分析深刻地揭示了互惠性偏好的前沿性,验证了互惠性管理策略在现代经济体系中存在着显著的应用价值,从而为我国企业加强互惠性管理战略、进而改进企业的运作绩效提供了现实性的理论借鉴。     

International borrowing without commitment and informational lags: Choice under uncertainty

A series of recent studies in economic growth theory have considered a class of models of international borrowing where, in the absence of a perfect investment commitment, the borrowing constraint depends on the historical performances of the country. Thus, a better level of past economic activity gives a higher reputation, thereby increasing the possibility of accessing the international credit market. This note considers this problem in a stochastic setting based on the volatility of the internal net capital. We study how the optimal consumption level and the maximal expected welfare depend on the combined influence of the trajectory of past economic variables and the volatile environment. In particular, we show how the strength of the history effect and the relative weight of the historical performance depend on the degree of risk.     

Accounting for Gender in a Study of the Motivation-Involvement Relationship

ABSTRACT

The effects of gender on involvement in high-risk recreation have received limited research attention despite mounting evidence suggesting the learned interactions between people and places likely vary for men and women. The purpose of this study was to provide insights into how gender influenced the motivation-involvement relationship among whitewater recreationists on a Wild and Scenic River in California. Our results revealed the motivations of Risk, Escape, Learning, and Achievement/Stimulation positively influenced involvement in rafting activities. Although gender did not influence all dimensions of involvement, we found that identity expression varied between subgroups. Specifically, men were more likely to ascribe meaning to rafting than women because this activity allowed them to affirm and express their individual character. The implications emanating from this study advance theoretical understanding of the factors that influence enduring involvement and inform natural resource management decisions about maintaining the desired benefits of activities sought by nature-based recreationists.     

Asymptotic stability of a general equilibrium under perfect and monopolistic competition

This study examines the asymptotic stability of a general equilibrium for an economy under perfect and monopolistic competition in which delays in a production process arise. Crucially, we find that the sufficient conditions for the stability of the equilibrium in each model differ markedly. For the stability of the equilibrium under perfect (monopolistic) competition, it is favorable that the slope of every demand curve is gradual (steep).     

The equilibrium exchange rates of European currencies and the transition to euro

This study estimates the demand system using Japanese micro data and calculates the cost of living index (COLI) to assess the substitution bias in the Consumer Price Index. The estimated bias during the sample period of 1982–2000 is about 0.06 percentage points, which is larger than the estimates calculated from a superlative index. The difference between the COLI and a superlative index can be explained with the upward movements of the average utility level in Japan, since the cost of living for the rich has grown more rapidly than that for the poor.     

Self-targeted food subsidies and voice: Evidence from the Philippines

This paper studies the targeting outcomes of a self-targeted rice subsidy program in the Philippines. We find modest within-community targeting outcomes, but weak between-community targeting. This appears to be because, controlling for the direct influence of household characteristics, participation was lower in poorer communities. These inter-community differentials are strongly correlated with several proxies for citizen “voice”, including education, income, and access to other public services. This suggests that self-targeting outcomes are not simply a function of the good selected for subsidy, but are also influenced by variations in communities’ access to usable services; that these variations favor richer communities; and that efforts to enhance consumer voice in disenfranchised communities would facilitate targeting improvements.     

普通顶管施工技术在一般工程中的应用

结合工程实例,对照施工规范,对普通顶管施工的各个关键过程分别加以分析和总结,提出了部分改进建议。     

一类具有无界时滞的微分不等式

本文建立了一类具有无界时滞微分不等式,将有界时滞微分不等式推广到无界时滞微分不等式,并得到其解的指数估计和渐近估计.