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31.
沈阳浑南大道作为沈阳市规划的重点工程项目,旨在将其打造成为具有系统性、整体性、生态性、文化性的景观廊道.充分考虑到了城市道路环境景观的特点,针对不同部位的特征,运用不同的设计理念及指导思想,提出相应的设计方法及方案,将其建设成为城市道路的精品工程.  相似文献   
32.
数控加工仿真对于零件实际加工过程具有一定的指导意义。在分析了产品制造系统、虚拟制造环境、数控加工仿真过程的基础上,提出了一种基于可重构虚拟制造环境的数控加工仿真方法;通过对虚拟制造环境的分析,研究了虚拟制造环境的层次结构,并将其抽象划分为四个层次;重点阐明了零部件模型、虚拟加工机床模型的可重构设计,从而实现了整个虚拟制造环境的可重构,并在此基础上建立了可重构的虚拟制造环境。最后,以船用柴油机机身零件的数控加工过程仿真为例,验证了该方法的可行性。  相似文献   
33.
周云  祁鹤 《北方交通》2007,(1):77-79
通过对青山沟互通式立交三个方案的比选,说明现今互通立交设计,在考虑地形、地质的基础上,保障安全、降低造价、行车舒适,同时也要重视环保,减少对自然环境的破坏,要顺势而为,与自然融为一体。  相似文献   
34.
针对两辆满足欧Ⅳ排放法规的汽油车,按照美国EPA 40 CFR PART 86法规进行了SC03空调试验,建立了SC03空调试验流程和操作指南,探讨了空调试验中温度、湿度、光照强度等环境变量及浸车时间对试验油耗结果的影响。基于田口法及环境变量的常用变化范围进行试验设计,通过统计学方法对试验结果进行假设检验,确定了对试验油耗影响较大的环境变量为温度和湿度,且两者之间相互独立,并通过实车试验对检验结果进行了验证。  相似文献   
35.
加快建设资源节约型,环境友好型社会迫在眉睫,其中构建有利于环境保护的交通运输体系是其关键之一.而发展高速铁路运输是构建可持续发展交通体系的核心.相对其他运输方式,铁路运输能源消耗低,污染排放少,综合性价比高,适合我国能源利用的要求,符合节能环保的要求.近几年,我国开展高速铁路建设,高速铁路相对普通铁路能源利用率更高,性价比更高,对环境的影响更小。  相似文献   
36.
引起寒区冻害的因素十分复杂,隧道冻害预防与整治是一项复杂而艰巨的工作。以运营的准池铁路杀虎口隧道为工程依托,设计合理的冻害防治监测系统,通过对监测结果的分析,预测冻害的重点防治范围。研究结果表明:距洞口500 m范围内围岩有冻结可能,围岩最大冻结深度1.55 m,排水量较大区段位于下坡端进口段1 300 m范围内,因此冻害重点防治区段为进口端500 m范围内的软岩区段,预测冻害类型以衬砌渗漏水、衬砌开裂为主。  相似文献   
37.
To examine whether there is a co-alignment relationship between environment risk, capital structure, growth and high-tech firm performance, the environment risk was measured from the viewpoint of environment change, the long-term debt ratio was adopted as the measure of the capital structure, and the total asset growth and sales growth were chosen to measure the growth of high-tech firms. Regression analysis shows that there is a significant relationship between environment risk, growth and performance of high-tech firms measured by the return on equity and cash flow, respectively.  相似文献   
38.
环境与人的关系是双向的,培养人的学校更是这样。作者以一个学校的校舍规划设计为例,说明作者对这一问题的理解,并依此做为设计的构思,使这个学校达到人创造环境,环境创造人这一目的。  相似文献   
39.
In order to select the correct mobility strategy, individuals’ choice behavior must be studied, and their reactions in response to strategies must be predicted. Upon exploring aspects subject to constraints, our results included walking distance, parking rates, search time and parking availability. We have identified scenarios in which simulation outputs of environmental parking mobility strategies differ significantly when using the Constrained Multi-Nominal Logit (CMNL) when compared with the widely used Multi-Nominal Logit (MNL). With the CMNL model growing in popularity, it is worth considering environmental mobility strategy repercussions in this context with the incorporation of relevant constraints.  相似文献   
40.
This study evaluates the link between the recruitment process of European hake (Merluccius merluccius L.) of the Balearic Islands (western Mediterranean) and the environmental and physiological conditions. Spatio-temporal variation of abundance and condition of fish were evaluated at two locations each with different oceanographic conditions, one in the north (Sóller, SO) and another in the south (Cabrera, CA) of Mallorca Island. Environmental variables explored were hydrography, sediment characteristics, phytoplankton pigment concentration (ppc) and the trophic resources of hake. Individuals were divided in three life stages: recruits, post-recruits and young adults. Hepatosomatic index (HSI), relative condition index (Kn), gonadosomatic index (GSI) and fullness index (FI) were analysed for the three life stages. Recruitment starts in February with the incorporation of smaller hakes, and it can be followed through spring and early summer with a peak in April. However, some spatial heterogeneity in the recruitment process has been found between north and south of the Island. The main pulse of recruitment occurred at a different time in the two areas. Spatial heterogeneity was also consistent with the condition of hake recruits, with higher values of Kn and HSI at SO than at CA. Maximum values of Kn were found in February at SO and in April at CA, coinciding with the start of the different recruitment pulses to the fishing grounds. Post-recruits and young adults also showed higher condition at SO than at CA. The arrival in spring of the Western Winter Intermediate Waters (WIW) drives the spatial-temporal variation in abundance and condition of hake. Ppc was highly correlated with recruit abundance with a time lag of two months, while for post-recruits the time lag was three months. The observed differences in the condition of hake between areas could be a consequence of the fact that the waters to the north of Mallorca are comparatively more under the seasonal influence of WIW which is formed in more productive areas. Thus, this study characterises the short temporal and spatial variability in the hake recruitment process off the Balearic Islands, both in terms of abundance and fish condition. This pattern is explained on the basis of the mesoscale environmental variability observed between north and south of Mallorca and the ecological adaptive strategy of recruiting in the optimal environmental season.  相似文献   
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