严寒地区高速铁路混凝土基床聚氨酯保温特性试验研究

基于严寒区京沈客专朝阳试验段路基基床的温度监测资料分析,研究不同厚度聚氨酯保温板对高速铁路路基混凝土基床温度变化特性影响.测试结果表明:①铺设聚氨酯保温板能够有效阻断严寒区环境与路基基床间的热量传递,保温效果与板厚相关;②地温大多数时间呈阳高阴低现象,同时阴、阳坡路基温差波动幅度随埋深逐渐减小;③基床表层阴、阳面各测点的温度变化起始时间一致,而阴面的冻结时间比阳面晚一个月.由此表明,保温板能够有效降低环境与混凝土道床之间的热交换,但是对路基阴、阳坡的影响存在差异.建议在严寒地区高速铁路路基阳、阴坡可以采取不同厚度的聚氨酯保温板,减小阴阳坡地温差异,保持季冻土路基温度变化稳定.     

Squatting as a transition problem in South Africa

This paper applies principles of transition to land tenure and squatting in South Africa. Political transition in South Africa reassigned political property rights, which produced contestable, and rent‐seeking incentives for squatting as a means to privatize land and redistribute wealth. Government failure to establish and protect private property rights in a squatter camp resulted in common‐pool problems that resisted private and public resolution with consequent rent dissipation and social loss. In response to this retreat from duty, informal agents emerged to claim their own share of the prize. Without enforceable rules of capture, the growth of squatter camps in South Africa will continue. JEL classification: D7, H8, K1, K4, R1, R4.     

A Critique of the Legal and Philosophical Case for Rent Control

Rent control is an economic abomination. It diverts investments away from residential rent units, it leads to their deterioration, it is responsible for urban decay such as in the South Bronx, it does not help poor tenants, it is a horrendous means of income redistribution. Yet this economic regulation is beloved of intellectuals (hot beds of pro rent control sentiment are Berkeley, Ann Arbor and Cambridge) particularly in the legal and philosophical communities. The present article is dedicated to an exploration and rejection of the arguments in behalf of rent control which emanate from this source.     

Vacancies and Rent Dispersion in a Stochastic Search Model with Generalized Tenant Demand

I model imperfect information, derive a downward sloping market demand curve, and explain vacancies in a partial equilibrium model of a rental housing market. Tenants can be completely described by an exogenous demand curve, perhaps arising from differences in income, preferred location, or tastes, and view vacant units based on a stochastic arrival of rental information. Free entry of these landlords induces excess rental housing capacity (equilibrium vacancies). I determine the equilibrium distribution of rents for vacant units, show that this rent distribution may be discontinuous, and explore the equilibrium vacancy rate to changes in exogenous parameters. The resulting characterization of equilibrium distributions of rents may be amenable to econometric modeling exploring the relationship between market rents and vacancies.     

雷达接收机数据采集平台及其FFT实现

介绍了小型化、通用化和实时信号处理要求下，雷达接收机的通用数据采集处理硬件平台。采用Xilinx公司最新平台级FPGA产品Spartan-3系列芯片构建平台，并实现其中的FFT于模块。试验表明，处理精度和速度都满足要求，为该方案的可行性和后续模块的实现提供了依据。     

行业间工资差异和垄断租金分享

以产业门类为基准测算的中国行业间工资差异明显且自1988年以来呈现逐步上升趋势，随着产业细分，行业间工资差异进一步提高。对劳动市场工资决定的理论分析表明，行业间工资差异主要源于各行业就业人员的人力资本差异和可能的垄断租金分享。实证研究中发现，就业人员性别、年龄和教育等就业人员特征只能解释行业平均报酬变差系数的60％左右，其余部分源于垄断行业的租金分享。其中，技术／知识型市场垄断行业租金分享比例不高，但非竞争性垄断行业普遍获得了超额报酬，约占其行业高工资的50％以上。后者超额报酬和超水平高福利主要源于相关行业无偿或低成本的自然资源占用和国有资产经营、攫取消费者福利、成本膨胀亏损的财政或社会公众补贴，因此要从其垄断机理和初次分配制度上改革以建立公平收入分配秩序。     

论政府信用失缺及其解决措施

从寻租的角度,主要运用政府官员和民众之间所形成的囚犯困境博弈,分析政府官员腐败产生的机制及原因,并提出相应的解决措施。     

Rent Seeking with Efforts and Bids

We introduce bids in a rent-seeking contest. Players compete for a prize. Apart from exerting lobbying efforts, they also submit a bid which is payable only if they win the prize. We show that our model has a unique Nash equilibrium in pure strategies, in which each active player submits the same bid, while the sum of all efforts equals that bid. In equilibrium there is underdissipation of rent.     

Open access,common property and scarcity rent in fisheries

Open access resources are frequently not managed efficiently, resulting in falling stock levels and a declining income for fishermen. In the late 1970's, the policy response to this problem was the implementation of 200-mile fishing zones, which enabled the European Union to formulate and implement the Common Fisheries Policy, aimed at (among other things) conservation and distribution of available stocks. In Germany, this shift from an open access regime towards a common property regime had favourable outcomes. The trend of falling prices was reversed. The conclusion was that intertemporal efficiency had increased as a result of (inter)governmental policy. Apparently, a wedge was formed between price and marginal harvesting costs, implying that scarcity rent had returned as a component of prices.     

Natural resources, capital accumulation and the resource curse

Early concern by economists for the effect of natural capital on economic growth gave way to complacency and neglect during the nineteenth century. Evidence has emerged, however, that since the 1960s the economic performance of low-income countries has been inversely related to their natural resource wealth. This relationship is not a deterministic one so policy counts. SEEA can help improve the policy and performance of resource-abundant low-income countries by reinforcing the rationale for the sound management of natural resources and also by providing an index of policy sustainability in the form of the net saving rate. This policy index, along with other measures such as a capital fund for sterilizing the rent, initiatives to increase the transparency of rent flows and the rigorous evaluation of alternative uses of additional public sector revenue can improve the efficiency by which natural resource rent is transformed into alternative forms of capital to sustain rising social welfare. Chad and Mauritania provide case studies to illustrate how SEEA and net saving can be used to diagnose policy failure and improve economic performance.