边界条件处理对曲轴有限元分析的影响研究

采用不同的边界条件对曲轴进行了有限元计算。计算结果表明,边界条件处理对曲轴有限元分析结果影响很大。为了提高计算结果的精度,有必要根据实际情况确定边界条件。     

试论农村宅基地征收补偿制度的完善

我国现行法律对农村宅基地征收补偿的规定存在诸多缺陷,主要表现在宅基地的补偿标准混乱、宅基地使用权及其上房屋的补偿标准缺失等问题。为避免征地纠纷、维护社会和谐稳定,必须制定宅基地所有权的征收补偿范围和标准,明确农民有权因宅基地使用权的丧失获得补偿,规定被征收房屋的补偿范围等。     

中原城市群道路交通与土地利用互动关系研究

文章运用系统分析法及文献资料法分析了中原城市群土地利用与道路交通的特点以及二者的互动关系。分析认为:中原城市群的建设用地矛盾突出,土地利用集约化程度不高;道路交通条件的改善促使本地土地价格上涨,加速了城市边缘区土地的开发;土地的开发利用,产生了巨大的交通需求,道路交通的增长不能完全满足高强度土地开发利用的需求。     

以HCCI燃烧过程为主要研究对象的模拟燃烧系统

所论述的模拟燃烧系统是针对均质混合气压燃特性试验研究开发研制的装置,主要由燃烧系统主体部分、混合气配给系统等组成。该装置具备定压燃烧过程、复合燃烧过程以及定容燃烧过程的研究试验功能,且具有良好的边界条件可控性。燃烧系统压缩终了压力可达到2.6MPa,活塞最高速度为5m/s,平均速度为2.18m/s。     

城市轨道交通企业多元化发展对比研究

城市轨道交通投资周期长、成本高、收益见效慢,许多轨道交通企业负债累累,但随着城市轨道交通在我国的高速发展,越来越多的轨道交通企业开启多元化经营进而实现多元化发展。本文列举了四个我国典型大都市的轨道交通多元化发展情况,结合政府颁布的土地政策,可以看出轨道交通多元化发展的重要性,以及政府将土地交由轨道交通企业自行开发、使用,政府在其中主要充当监管者的角色。这样有助于实现其多元化经营,进而带动多元化发展与城市可持续发展。     

Environmental justice and hazmat transport: A spatial analysis in southern California

This paper explores whether the risk of a toxic release during transport is greater in poor and minority neighborhoods using a combination of mapping and statistical methods. Cluster analysis is used to examine the density of facilities and transport spill events as well as test for the spatial covariance between facilities and spills. Strong clustering of transport spills is evident, as well as clustering between factory sites and transport spills. A spatial model demonstrates raised rates of transport spills surrounding clusters of toxic firms. Most spills in Los Angeles occurred within 2 km of an intermodal facility. The last step of the analysis compares risk and facility clustering between neighborhoods and socio-economic groups, finding that hazmat spills during transport disproportionately occur in Latino neighborhoods in Los Angeles. The results clarify the spatial distribution of risk and nuisance from freight in urban landscapes.     

内燃机排气消声器声学边界元模型的建立及其应用

本文提出了分析内燃机排气消声器内二维声场的有效方法,采用二维坐标将声压作为未知参数,描述了排气消声器二维声学边界元模型的建立及其在492Q汽油机消声器中的应用,计算的插入损失与实测结果具有很好的一致性,研究结果表明二维声学边界元模型是分析排气消声器的有效方法并具有较高精度。     

谈铁路征地拆迁验工计价管理

在铁路工程建设中,加强建设项目征地拆迁验工计价管理,不断完善验工计价管理体系,是保证建设资金合理、安全使用和征地拆迁工作顺利进行的重要措施。此文在论述征地拆迁应采用统一标准确认拆迁工程量、计算原则、拆迁范围和补偿标准的基础上,提出只有做好各类资料的归集与审查,完善征地拆迁验工计价程序,才能做好相关工作,并建议国家有关部门应尽快制定配套措施,以保证工程建设中征地拆迁工作的顺利进行。     

Spatial and temporal distribution of expressway and its relationships to land cover and population: A case study of Beijing,China

The interaction between urban transport, land cover change and the distribution of population is a typical manifestation of the urbanization process. As high-grade road, expressway plays a significant role in promoting resource circulation and economic development. Based on the road distribution, land cover and population census data, this study specifically probed the relationship between the expressways and the land cover and population of Beijing. The results show that: (1) as the distance from an expressway increases, the amount of built-up land gradually decreased, and the transfer of land cover near the expressway was more intensive and frequent when compared with that of the whole city; (2) In 2010, a district that was less than 3 km from both sides of the expressway and which occupies one-quarter of the entire city had concentrations of 42% industrial land, 58% of settlement land, and 76% transportation land of the entire city; (3) As for Beijing, the population density was positively correlated to road density, and population density declined with a corresponding increase in buffer distance; (4) The ring area between the Fifth and the Sixth Ring Road featured the greatest density of expressways and the most dramatic changes in both land cover and population. According to our study, there’s a positive interactive feedback relationship between the expressways, land cover and population of Beijing. Also, due to the concentration of population, industry and transport system around the expressways, special attention should be paid to environmental pollution and the inhabitants’ health in this area.     

Integrating transport and land-use planning? How steering cultures in local authorities affect implementation of integrated public transport and land-use planning

Previous research has shown integrated planning to be important for achieving aims concerning more environmentally friendly transport operations, but less good at explaining prerequisites of implementation. This paper analyses how management and working practises in local authorities, here understood as steering cultures, affect implementation of integrated land-use and public transport planning approaches. The analysis builds on case studies of planning in two Swedish municipalities. These have developed two antithetical steering cultures, namely one that can be described as deliberative and one that can be described as sectorised. The paper describes the advantages and disadvantages of these steering cultures. The findings show the deliberative model to facilitate integration through advanced mechanisms of consensus and co-ordination between policy-makers and officials. The sectorised model has no such mechanisms, but this need not result in poor prospects of integrated planning. It is important for integrated planning approaches, whatever the steering culture, to be in line with the institutionalised norms and objectives by which planning practices are governed. Integration therefore needs a normative component, so as to ensure implementation. The important normative component in this context can be construed as discourses and rationales concerning transport and the urban development of which public transport forms part.