正度拟齐次Toeplitz算子的乘积

在Bergman空间上讨论了以拟齐次函数为符号的Toeplitz算子的乘积问题.使用Mellin变换作为工具,得出了当拟齐次函数的度都为正度时两个Toeplitz算子乘积仍是Toeplitz算子的充分必要条件,完善了以往文献中的有关结果.     

The “swing of the pendulum” from public to market support for science and technology: Is the U.S. leading the way?

The structure and financing of science and technology activities are undergoing a slow, but profound, change. This change can be briefly characterized as a shift from relying and supporting public science to a stronger emphasis on “market-based” incentives for science and technology. In this paper we analyze this shift in a historical perspective, discussing both the theoretical explanations and the empirical trends of the ongoing change. While we do not claim to provide a comprehensive and exhaustive identification of the causes of this shift, we argue that it is largely driven by the perception of a shift of the U.S. policy towards market-based, rather than publicly supported, incentives for science and technology. This, in turn—given the strong economic performance of the United States over the 1990s—has influenced policies in most OECD countries, especially in Europe.We conclude by analyzing the evolution of research in U.S. higher education and find two major trends: an increasing diversity in the number of institutions of different types other than universities and a steady and continuous public funding of the leading U.S. universities. This has allowed the construction of an infrastructure now used largely by the private sector, but it also noted that the United States has not compromised public support for core areas or in those fields in which there is a clear perception that market incentives are not sufficient for meeting the strategic targets of the U.S. policy. The implication is that there is a considerable policy diversity in the U.S. practice and that all aspects of this diversity should be considered when using the United States as a reference.     

Interpreting IS alignment: A multiple case study in professional organizations

This paper centers on the interpretation attributed by organizational members to the information systems (IS) alignment concept. Its objective is to study IS alignment in professional organizations. Specifically, it reports on an interpretive study conducted in five Chilean organizations; four professional and one entrepreneurial, of which two are private and three are public. The theoretical background of our study is derived from three IS strategic alignment conceptualizations: managerial, emergent and critical. These concepts formed our theoretical framework that guided data collection and analysis. The study centers on the meanings organizational members assigned to IS strategic alignment, as well as their views on the barriers that hinder achieving this level of organizational integration. The analysis results are summarized in seven hermeneutic themes that point out the different connotations the organizations assigned to IS alignment. The significance of the findings are summarized in four insights that formulate theoretical and practical implications. These insights refer to: (1) the difficulties of achieving alignment for professional organizations, particularly public ones, (2) the limitations these organizations have in being agile, (3) the rationale for acquiring technology and determining IT skills, and (4) the imperative meaning that CIOs attribute to IS alignment. The paper concludes with a reflection on the limitations and relevance of the research.     

Lotus Domino/Notes的公开密钥加密机制

公开密钥加密技术在最近几年得到了极大的重视和发展。本文讨论了公钥加密技术的原理和实施技术，并结合公钥技术在Lotus Domino/Notes中的应用，着重探讨了Lotus系统内部用户校验和认证机制的建立和实施。     

CREDIBILITY, MACROECONOMIC FUNDAMENTALS AND MARKOV REGIME SWITCHES IN THE EMS

The main objective of this paper is to use the Markov regime‐switching modelling framework to describe and analyse the credibility of a number of countries participating in the European Monetary System during 1980–1998. Our credibility indicator, based on Hughes Hallet et al.'s (1997) methodology, is subject to discrete regime shifts and is made dependent on macroeconomic fundamentals. We carry out extensive testing to assess the specification of the Markov regime‐switching model and the potential existence of permanent breaks. A contribution of our paper is the specification of a multivariate Markov switching model that allows us to examine whether macroeconomic variables have asymmetric effects on credibility. Another contribution is the specification of a regime‐switching model with time‐varying transition probabilities, which enables us to determine whether changes in macroeconomic variables can trigger switches between the low and high credibility regimes. We find strong evidence of regime switching behaviour in all countries. Both the level of credibility and the transition probabilities display an asymmetric response to changes in macroeconomic variables, with the stance of fiscal policy exerting the most systematic influence in all countries.     

东部地区农业结构变动与政策变量之间的相关性研究

本文通过农民收入变量、农民受教育程度、农村人均固定资产投资额、政府用于农村人均文教娱乐用品及服务支出和政府用于农村财政支出等政策变量与东部地区农业结构变动的相关性分析,再根据未来若干年我国及东部地区农业政策变化趋势,从而预测未来我国东部地区农业结构的变化趋势。     

Labor taxation, public finance, and wage determination: evidence from OECD countries

This paper analyzes the relationship between unemployment, average effective labour tax rates and public spending in 17 OECD countries. The focus is on the degree of centralization and cooperation in wage setting. Estimation results from a dynamic time-series-cross-section model suggest that the countries where wage setting takes place at the firm level have used labour taxes less extensively in financing welfare spending, compared to countries with centralized or decentralized bargaining. This is consistent with another finding, according to which labour taxes distort the labour demand the least in the countries with firm level bargaining.     

Are We Better Off if Our Politicians Have More Information?

The model of public policy studied in this paper has heterogeneous citizens/voters and two public goods: one (roads) chosen directly by an elected policy‐maker, and the other (pollution) stochastically dependent on the amount of roads. Both a one‐country and a two‐country version of the model are analyzed; the latter displays externalities across the countries which create incentives for free riding and strategic delegation. The welfare effects of providing the policy‐maker with information about the relationship between roads and pollution are investigated, and it is shown that more information hurts some—sometimes even all—citizens. In particular, the opportunity not to create an institution for information gathering can serve as a commitment device for a country, although with the unfortunate effect of making the overall outcome even worse. Implications for the welfare effects of “informational lobbying” are also discussed.     

基于DSRC和CDPD的先进公交系统

本文首先讲述了ITS中的2种通信技术——专用短程通信（DSRC）和蜂窝数字分组数据网（CDPD）的基本概念、工作原理及系统特点等，然后提出了一种基本这2种通信技术的先进公交系统，并对各个子系统的功能结构进行了描述。     

不同财务管理目标下业绩评价选择及其关系处理

从财务管理目标出发考察企业业绩评价方法的演变过程，是为了在它们之间建立一种联系。不同的财务管理目标下，企业的业绩评价选择会有很大的差异，而其总体趋势是选择综合业绩评价方法。在不同的财务管理目标下选择不同的业绩评价指标时，又要处理好三对关系：短期发展与长期发展、局部利益与全局利益、财务指标与非财务指标。