抗SPA攻击的快速LSB均衡隐藏算法

提出了一种新的LSB隐藏方法,根据待嵌载体图像像素值的奇偶性和嵌入信息的内容,选择像素值加1或加2的嵌入方式,使得SPA(sample pair analysis)攻击的假设条件在嵌入前后保持平衡,致使SPA攻击失效。在使用该方法嵌入率达到100%时,SPA攻击的估计值仍然小于判决门限。实验不仅验证了新方法抵抗SPA攻击的能力,也验证了新方法可以抵抗RS等检测。新方法嵌入方式简单,且无需在嵌入后再做附加处理,便于实现。     

浅谈可逆反应的化学平衡

化学平衡是研究可逆反应的一个重要内容。本文从可逆反应与不可逆反应、化学平衡、化学平衡常数等方面对其进行了初步探讨。     

论博弈逻辑的分析方法——纳什均衡分析法

博弈逻辑是逻辑学研究的一个崭新领域，目前处于初创时期。文章探讨了博弈逻辑的基本分析方法——纳什均衡分析法，并对其进行了评价。     

Global Trade Models and Economic Policy Analyses: Relevance,Risks and Repercussions for Africa

Computable general equilibrium models are widely used for trade policy analyses and recommendations. There is, however, increasing discomfort with the use of these models, especially in Africa. This article demonstrates that the results of several such studies of the impact of trade reforms in Africa differ drastically in terms of both magnitude and direction, failing to take account of key features of African economies. It also outlines potential consequences of the misuse of CGE models for policy evaluation and suggests pitfalls to be avoided.     

邓小平辩证发展观与和谐社会的构建

研究邓小平辩证发展观时,学术界往往较多关注其非均衡发展思想,而忽略对其"综合平衡"均衡发展思想的研究,针对这一现状,分析了邓小平均衡与非均衡辩证发展观及其对构建和谐社会的作用。分析认为:均衡发展不是社会各方面同步发展,非均衡发展并非是"单打一"的发展;均衡与非均衡发展应是在差异基础上的"和谐"共进,是均衡发展与非均衡发展的有机统一。当前重新认识和深刻领会邓小平辩证发展观对于和谐社会的构建无疑具有重要的现实意义。     

基于行程时间可靠性的随机交通网络均衡模型

考虑现实条件下交通网络的不确定性状态，提出了从确定型网络到不确定型网络状态下出行者路径选择行为的改变，及基于行程时间可靠性的路径选择模型。并将可靠行程时间的路径选择行为纳入到随机交通网络平衡分配模型中，证明了模型的等价性和唯一性。在一个小型测试网络上对模型分配结果进行了测试，测试结果与经验相吻合，表明模型具有较好的现实可行性。     

Comment on An and Schorfheide's Bayesian Analysis of DSGE Models

An and Schorfheide's article provides an excellent review of Bayesian estimation of DSGE models. Rather than recapitulating the points already made in this article, my comment focuses on three aspects. It proposes a convergence measure to take account of serial correlation of MCMC draws, explains why the DSGE-VAR framework for policy analysis can be improved by avoiding the ad hoc identification assumption, and discusses an alternative structural approach to model misspecification.     

德育资源及其开发利用

德育资源是指可以运用于德育过程、能够给受教育者的思想道德产生积极影响的一切现实和潜在的因素。相对于德育条件,德育资源具有更高的抽象性、概括力,更大的通用性、普适性,更鲜明的主体性、积极性。德育资源的优化配置、高效利用、持续开发是构成健康德育资源观的基本内容。     

Procurement with Reverse Auction and Flexible Noncompetitive Contracts

This article investigates a hybrid procurement mechanism that combines a reverse auction with flexible noncompetitive contracts. A buyer adopts such mechanism to procure multiple units of a product from a group of potential suppliers. Specifically, the buyer first offers contracts to some suppliers who, if accepting the contract, do not participate in the auction while committing to selling a unit to the buyer at the price of the subsequent auction. For the suppliers rejecting the offers, they can join the subsequent auction with the other suppliers to compete on the remaining units. When the buyer offers only one flexible noncompetitive contract, we find that the selected supplier may accept the offer regardless of whether he knows his exact cost information. Meanwhile, the buyer can benefit from offering such a contract, as opposed to solely conducting a regular reverse auction or offering a noncompetitive contract that does not allow suppliers declining offers to join the subsequent auction. Moreover, we find that the suppliers' information about their own costs has a significant impact on the buyer's decision. When the buyer makes multiple offers, we analyze the resulting game behavior of the selected suppliers and demonstrate that the buyer can benefit more than just offering one such contract. Therefore, the hybrid procurement mechanism can be mutually beneficial for both the buyer and the selected suppliers.     

Competition and Coordination in Two‐Tier Public Service Systems under Government Fiscal Policy

As a result of government budgetary limits and rapid market growth, many public service systems—such as health care—are characterized by extensive customer wait times that have become a serious problem. This problem might be solved by allowing private firms to enter these markets, which would provide customers with a choice between a free (governmental) public service provider (SP) and a fee‐charging (or “toll”) private SP. In such a two‐tier service system, the two SPs are differentiated by service quality and cost efficiency. This study focuses on the competition and coordination issues for two‐tier service systems with customers who are sensitive to both service quality and delay. The free system attempts to maximize its expected total customer utility with limited capacity, whereas the toll system attempts to maximize its profit. Neither goal is aligned with the social welfare goal of the public service. To achieve the social welfare goal, the government plays a crucial role in coordinating the two‐tier service system via the budget, the tradeoff of social members' goals, and tax‐subsidy policies. Using a mixed duopoly game, we establish Nash equilibrium strategies and identify the conditions for the existence of the two‐tier service system. We employ several interesting and counter‐intuitive managerial insights generated by the model to show that the public service can be delivered more efficiently via customer choice and SP competition. In addition, we show that a relatively low tax‐subsidy rate can almost perfectly coordinate the two SPs to achieve most of the maximum possible benefit of the two‐tier service system.