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151.
土地资源可持续利用中的利益均衡:土地发展权配置   总被引:9,自引:1,他引:9  
土地是社会的、政治的、经济的权利源泉,它反映了一定的社会经济结构。土地的制度演变是一个有关利益主体的社会博弈过程。实行土地资源整理有利于提高土地利用效率,是解决社会发展中土地供求矛盾的有效途径,选择利益均衡的土地整理策略能优化土地资源的社会经济效用,其中土地发展权的创设与合理配置是实现土地资源可持续利用的关键。  相似文献   
152.
设计了一个平衡约束条件下信号控制与平衡网络设计组合问题的多目标规划模型,然后使用效用函数法将有双目标的上层优化问题转化为一个单目标优化问题.在这种情况下,该模型变成一个标准的双层规划模型。并利用全局优化方法模拟退火算法和惩罚函数法相结合求解.  相似文献   
153.
基于时间价值不同的多类型用户特性,提出了弹性需求下多类型用户的拥挤收费模型,并以一个简化的路网实例比较了多类型用户收费模型与单一类型用户收费模型的区别。简化实例分析结果表明:当费率水平较低时,单一类型用户收费模型高估了路网的流量、社会效益,当费率水平较高时,则低估了路网的流量和社会效益;同时单一类型用户收费模型的路网社会效益和利润区域对应的道路通行能力区间较宽,费率水平区间窄,而多类型用户收费模型的路网社会效益和利润区域对应的道路通行能力区间相对较窄,费率水平区间较宽。  相似文献   
154.
随着中国铁路"走出去"倡议的实施,中国标准体系下各设计阶段主要工作内容及方法在国外项目的应用差异性问题日益凸显。为提高中国企业参与国外铁路勘察设计进程,依据多个海外项目设计经验,通过对比分析国内外铁路设计过程的各阶段工作方法与特点,分别对国外项目前期研究、项目设计和工程实施3个阶段的主要工作内容及审批程序进行分析。研究认为,国外铁路项目设计各阶段工作内容与我国设计标准体系有一定差异,但存在对应关系;其中,可行性研究报告是前期研究阶段重要成果文件,编制深度可参考国内的预可行性研究;设计阶段一般细分初步设计和详细设计两阶段,文件编制深度由国内的可行性研究逐步过渡到初步设计;实施阶段重点落实施工图工作。  相似文献   
155.
It is sometimes argued that standard state-of-practice logit-based models cannot forecast the demand for substantially reduced travel times, for instance due to High Speed Rail (HSR). The present paper investigates this issue by reviewing the literature on travel time elasticities for long distance rail travel and comparing these with elasticities observed when new HSR lines have opened. This paper also validates the Swedish long distance model, Sampers, and its forecast demand for a proposed new HSR, using aggregate data revealing how the air–rail modal split varies with the difference in generalized travel time between rail and air. The Sampers long distance model is also compared to a newly developed model applying Box–Cox transformations. The paper contributes to the empirical literature on long distance travel, long distance elasticities and HSR passenger demand forecasts. Results indicate that the Sampers model is indeed able to predict the demand for HSR reasonably well. The new non-linear model has even better model fit and also slightly higher elasticities.  相似文献   
156.
This study examines the potential effects the installation of seat belts on school buses would have on the fleet capacity in Alabama and the resulting cost implications. The study also documents the myriad research studies and professional opinions offered on the potential safety effects of equipping school buses with safety restraints/seat belts. Four seat configurations for the school buses were analyzed. The first configuration represents the most common current bus seating configuration without seat belts, 3 seats on each side of the aisle and 12 rows (3/3-12). The physical space required for seat belt hardware may result in a loss of a row of seats and may reduce the number of students seated per row. Thus, three more configurations were studied: loss of a row of seats (3/3-11), loss of one seat per row (3/2-12), and loss of both a row of seats and a seat per row (3/2-11). The capacity for each configuration for each bus using current pupil loads was determined. The costs associated with installation of seat belts, and purchase and operation of new buses were obtained. Should school bus seat belts become mandatory in Alabama, the results obtained in this study can be used by any school system to determine the optimum configuration for their pupils, which will identify the number of additional buses that must be purchased by the school system. This study found that many of the buses that would become overloaded due to seat belt installation and the resultant loss of seating will be carrying only a few excess pupils. Transportation supervisors may be able to handle such overloads by transferring these pupils to other buses or by adjusting their bus routes to minimize purchase of new buses. Additional suggestions for handling bus overloads were offered in the body of this report.  相似文献   
157.
该文以永蓝高速公路工程应用机制砂于混凝土为实例,对机制砂混凝土与河砂混凝土的性能进行了比较,阐述了机制砂混凝土配合比设计中的几个关键步骤及应注意的问题,并阐述了机制砂代替天然砂应用到混凝土中的体会,指出了采用机制砂混凝土不仅可提升资源利用率,节约建造成本,又可保证工程质量。  相似文献   
158.
This paper tests a group decision-making model to examine the school travel behavior of students 6–18 years old in the Minneapolis-St. Paul Metropolitan area. The school trip information of 1737 two-parent families with a student is extracted from Travel Behavior Inventory data collected by the Metropolitan Council between the Fall 2010 and Spring 2012. The model has four distinct characteristics including: (1) considering the student explicitly in the model, (2) allowing for bargaining or negotiation within households, (3) quantifying the intra-household interaction among family members, and (4) determining the decision weight function for household members. This framework also covers a household with three members, namely, a father, a mother, and a student, and unlike other studies it is not limited to dual-worker families. To test the hypotheses we build two models, each with and without the group-decision approach. The models are separately built for different age groups, namely students 6–12 and 12–18 years old. This study considers a wide range of variables such as work status of parents, age and gender of students, mode of travel, and distance to school. The findings of this study demonstrate that the elasticities of the two modeling approaches differ not only in the value, but in the sign in some cases. In 63% of the cases the unitary household model underestimates the results. More precisely, the elasticities of the unitary household model are as much as 2 times more than that of the group-decision model in 20% of cases. This is a direct consequence of model misspecification that misleads both long- and short-term policies where the intra-household bargaining and interaction is overlooked in travel behavior models.  相似文献   
159.
结合工程实际,介绍了"安全、舒适、美观、和谐、经济、耐久"在鹤大线山区公路的应用情况.  相似文献   
160.
基于同步碎石封层作为沥青路面预防性养护措施的研究现状,分析其预防性养护特征,同时从材料选择、施工设备和施工工艺三个方面出发,对该项养护技术进行全面、深入的研究。通过试验路的实施与监测,验证了同步碎石封层技术对路用性能的改善效果;通过预防性养护技术经济效益对比分析,认为同步碎石封层具有造价成本低、预期寿命长的优点。  相似文献   
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