中央政府与地方政府风险基础建设的静态博弈研究

运用静态博弈模型对我国风险行业安全生产基础设施建设中存在的中央政府和地方政府博弈的现象进行了理论研究。研究结果与实际情况较为吻合,但是由于忽视了激励机制,所以该模型并不能为政府提高中央预算的比例提供理论依据。     

Decision Support System of Truck Routing and Refueling: A Dual‐Objective Approach

The variable‐route vehicle‐refueling problem (VRVRP) is a variant of the network‐flow problem which seeks, for a vehicle traveling from origin s to destination d, both the route and the refueling policy (sequence of fuel stations to use between s and d) that jointly minimize the fuel cost of operating the vehicle. Commercial‐grade decision support systems that solve the VRVRP are widely used by motor carriers, but they provide heuristic solutions only. Exact methods are available from the academic side, but because they focus on minimizing costs, they tend to cut fuel costs in exchange for increased vehicle miles (which can increase fuel consumptions and pollutants emission). We propose a new approach to the VRVRP that allows carriers to jointly seek the two possibly conflicting goals; minimizing fuel cost and vehicle miles. Computational testing shows that our approach (i) outperforms the commercial software products in both goals, and (ii) finds solutions that require significantly less vehicle miles than those given by the exact method proposed in the academic literature, without incurring unacceptable increases in fuel cost.     

BOT项目公司固定资产折旧会计方法选择分析

通过对我国运用BOT模式的分析,以路（桥）类固定资产为例,探讨了BOT项目公司固定资产折旧会计方法的选择问题。     

论邓小平经济结构调整的思想

从经济结构调整的必要性、思路和重大意义等几个方面论述邓小平经济结构调整的思想。邓小平认为:经济结构调整是经济走向正常发展的必要前提,是我国经济健康、协调、快速增长的客观要求,是顺应世界科技经济发展大趋势的必然选择;调整的思路是把农业放在整个经济发展的战略重点,加强基础产业和基础设施建设,优先发展教育和科学技术。邓小平关于我国经济结构调整的思想,对我国目前社会经济的发展仍具有重要的指导意义。     

我国高校信息化建设发展路径探析

高校信息化建设是教育改革发展的助推器,也是实现教育跨越式发展的重要手段和途径之一。信息技术引发的社会变革对高等教育的教学与管理观念、模式、手段、工具等方面产生冲击。通过对我国高校信息化建设现状及问题的剖析,探讨高校信息化建设的发展趋势,进而从领导重视、正确认识、开发资源、建设队伍等方面提出对策与建议,说明加强高校信息化建设的重要性和紧迫性。     

近年来国外城市交通政策和技术研究述论

城市形成本身与空间密不可分。城市交通作为一种征服、跨越空间的方式,是城市系统中最重要的部分之一。国外特别是欧美国家面临严峻的交通问题,除了减少私家车用量外,还运用了一些技术手段和影响人们行为方式的公共政策,这对于中国的城市交通管理与改善有一定的启示和借鉴意义。     

公交车辆在中途站点的排队论分析

公交站台停靠区的排队问题决定了公交车辆的通行能力。把公交中途站台与公交车辆模拟成一个单服务系统、公车到达率 ,两服务率 、 的负指数分布的排队M/M/1/N系统。根据排队论理论,实测计算了北京中关村海淀黄庄、人民大学站点公交车辆排队队长,站内逗留时间等参数。结论为：城市主干道关键站台改造为主、副双公交站台制式以及调整公交线路布设,优化各线路发车频率是花费成本低,畅通成效大的解决站点塞车排队的方法。     

我国BOT投资发展特点与前瞻

分析BOT投资的特点、优势,阐述运用BOT是我国经济建设的必然选择,进一步提出完善我国发展BOT投资的措施.     

农业基础设施对农村经济影响的动态分析

农业基本建设支出的增长拉动了农业生产值的增长;农业生产值的短期波动偏离长期均衡时,基本建设支出将以一定的调整力度将非均衡状态拉回到均衡状态;农业基本建设支出增长对农业生产的增长表现为负冲击,也就是说农业生产的增长量在减少,这是符合要素的边际报酬递减规律的;农业基本建设支出对农业生产的短期效果没有长期效果明显稳定,即农业基本建设支出对农业生产总值有稳定的推动作用,这一研究结论与相关文献研究的结论相一致。当前,以农田水利为重点大力加强农业基础设施建设,必须改革公共产品二元供给制度,利用法律手段与创新方式,建立"自下而上"和"自上而下"相结合的农业基础设施决策机制。     

A review of tree root conflicts with sidewalks,curbs, and roads

Literature relevant to tree root and urban infrastructure conflicts is reviewed. Although tree roots can conflict with many infrastructure elements, sidewalk and curb conflicts are the focus of this review. Construction protocols, urban soils, root growth, and causal factors (soil conditions, limited planting space, tree size, variation in root architecture, management practices, and construction materials) are discussed. Because costs related to sidewalk and curb damage are substantial, a review of research addressing repair, mitigation, prevention, and litigation costs is included. Finally, future research needs are discussed.

Potential for conflicts between trees and sidewalks/curbs is high when one or more of these factors are present: tree species that are large at maturity, fast growing trees, trees planted in restricted soil volumes, shallow top soil (hard-pan underneath top-soil), shallow foundations underneath the sidewalk (limited or no base materials), shallow irrigation, distances between the tree and sidewalk of less than 2.0–3.0 m., trees greater than 15 to 20 years old.

The results of this survey indicate that cities are spending substantial sums of money to address conflicts between street tree roots and infrastructure. It can be inferred that most of these expenditures are spent dealing with problems that already exist. However, this raises the question: How much is being spent now to ensure that conflicts are minimized in the future?

Future research should concentrate on plant factors, site design, and construction of sidewalks and curbs. Also, more knowledge is needed about interactions between root growth and management techniques, such as pruning and irrigation. Finally, there is need for studies that will assist policy-makers to efficiently allocate funds among repair, mitigation, prevention, and legal remedies.