高速铁路车站到发线运用优化研究

高速铁路车站到发线运用计划根据列车运行计划、动车组交路计划编制各列车占用到发线的起止时间,以均衡、合理使用到发线和方便旅客上下车为原则,为每一列车安排合适的到发线。在分析高速铁路车站到发线运用特点和原则的基础上,建立高速铁路车站到发线运用的0-1规划模型,并利用遗传算法求解。通过算例分析,编制长沙南站的到发线运用方案,说明方法的具体应用。     

Backpacker ethnography

This paper presents an ethnographic study of the travel culture of international backpackers. Their sociodemographic characteristics are described, the contours of a concept of tourism culture are delineated, and on that basis, that of backpackers is outlined, with particular focus on the key phenomenon of road status. The analysis of backpacker tourism as a culture furthers the comprehension of change within the phenomenon. Examples of factors of change include the guidebooks, the short-term backpackers, and in particular the internet. This study demonstrates the merit of a dynamic concept of culture where culture takes place whenever activated by social circumstances.     

入世后金融创新的国际扩散对我国金融业的影响

在目前我国金融创新研发能力还比较低的情况下，通过扩散方式进行金融创新是我国金融创新的主要形式。对入世后金融创新国际扩散对我国金融业的影响进行了分析。     

Bailey's Measure of the Welfare Costs of Inflation as a General-Equilibrium Measure

Lucas (2000) has shown that Bailey's formula for the welfare costs of inflation can be regarded as an approximation to the general-equilibrium measures that emerge from the Sidrauski and the shopping-time models. In this paper we show that Bailey's measure can be exactly obtained in the Sidrauski general-equilibrium framework under the assumption of quasilinear preferences. The result, based on whether or not wealth effects are incorporated into the analysis, is also helpful in clarifying why Lucas' measure derived from the Sidrauski model turns out to be an upper bound to Bailey's. Two examples are used to illustrate the main conclusions.     

Calculating the cost of irrigation induced soil salinization in the tungabhadra project

Irrigation projects in developing countries have a history of poor performance. Inefficiencies result as water applications deviate from plans and induce greater than projected rates of soil degradation through water logging and salt accumulation. Over time, the collective impact of these forces will converge to an equilibrium with a level of output that may be far below the system’s potential. The Tungabhadra Project in south west India is experiencing all of these problems. Integrating geographic, hydrologic, biologic and economic features, the lost production value is estimated for a range of equilibria to which this system may converge. For the lower left bank main canal of the Tungabhadra project, the total economic cost of soil degradation are approximately 14.5% of the system’s productive potential while sub-optimal distribution losses may approach 37.1%.     

A historical overview of financial crises in the United States

One of the few constants since the United States declared its independence is the presence of frequent financial crises with similar causes. In the nineteenth century, these panics were frequent with eight occurring over the century. However, following the Second World War there was a period of relative calm, which may have led to complacency. The Savings and Loans and the current financial crises have shown that these events remain a very real threat to economic stability.     

The financial crisis: What is there to learn?

Many are currently studying the origins of the financial crisis in an attempt to answer two seemingly simple questions: why did it happen, and can another crisis be prevented? Those two questions have proved incredibly divisive. The majority opinion of The United States Financial Crisis Inquiry Commission was submitted with two dissenting positions. Furthermore, The 2010 Economic Report of the United States President does not perfectly align with any opinion presented in that report. Few studies, however, provide proper consideration to the evolution of macroeconomic thought and lengthening of the business cycle preceding the current crisis.     

The general dynamic factor model: One-sided representation results

Recent dynamic factor models have been almost exclusively developed under the assumption that the common components span a finite-dimensional vector space. However, this finite-dimension assumption rules out very simple factor-loading patterns and is therefore severely restrictive. The general case has been studied, using a frequency domain approach, in Forni et al. (2000). That paper produces an estimator of the common components that is consistent but is based on filters that are two-sided and therefore unsuitable for prediction. The present paper, assuming a rational spectral density for the common components, obtains a one-sided estimator without the finite-dimension assumption.     

Regional Grants: Are They Worth It?*

Regional grants have recently come under scrutiny and are controversial. Some estimates put the employment effect of these grants at no more than 6,000 jobs in the first half of the 1990s, against expenditure of £500 million. Other aspects of the grants are questioned, such as their ability to attract foreign direct investment and their effect on productivity. This paper reviews these issues, focusing on the recent evidence for the Regional Selective Assistance scheme. It describes the nature and difficulties involved in policy evaluation, and finds that differences over the employment effect of the grants result from possible biases induced by the evaluation methodology and from differences in the job measure used. Overall, the paper argues that the regional grants are cost‐effective in employment terms, but that expenditure is small relative to the scale of the problem, so that an expansion of the grants may be desirable.     

零担货物配装模型与算法研究

配装是铁路零担货物发送的关键,为取得最优配装方案,应以货车静载重和装载容积最大为优化目标。为此对两个优化目标分别建立0-1规划模型,并利用有序组合树法求解出最优解。通过算例得到两个不同方案,说明一般应优先考虑货车静载重最大,并在此基础上考虑充分利用车辆容积的方案。