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71.
上海迪士尼主题乐园项目落户于上海浦东新区黄楼镇,根据总体规划,除主题游乐场外,周边区域将逐渐发展成为上海国际旅游度假区。为适应主题乐园及度假区产生的交通吸引,自2005年起,相关部门便组织展开了主题乐园总体规划及其配套设施的研究工作,并有针对性地提出了对上海市现有骨干路网的调整与补充,相关工程的方案和研究工作也在进一步深化中。在对总体交通规划过程进行回顾的同时,归纳总结目前配套道路的方案成果,以供进一步探讨和改进。  相似文献   
72.
随着汽车工业的发展和人民生活水平的日益提高,汽车已走进了千家万户。人们不但追求汽车的安全性、可靠性、更注重它的舒适性,汽车空调也就成为现代汽车上的一项基本配置了。因此,车主们对汽车空调的正确使用,如何养等方面知识的需求越来越高多。根据车主们的需求,本文以通俗易懂的形式讲述了调的工作原理、正确使用和维护保养。  相似文献   
73.
Uncertainty is inherent in major infrastructure projects, but public decision-making for such projects ignores it. We investigate the uncertainty about the future effects of tearing down the Alaskan Way Viaduct in downtown Seattle, using an integrated model of housing, jobs, land use and transportation, on outcomes including average commute times. Our methodology combines the urban simulation model UrbanSim with the regional transportation model. We assess uncertainty using Bayesian melding, yielding a full predictive distribution of average commute times on 22 different routes in 2020. Of these routes, 14 do not include the viaduct and eight do. For the 14 base routes that do not include the viaduct, the predictive distributions overlap substantially, and so there is no indication that removing the viaduct would increase commute times for these routes. For each of the eight routes that do include the viaduct, the 95% predictive interval for the difference in average travel times between the two scenarios includes zero, so there is not strong statistical support for the conclusion that removing the viaduct would lead to any increase in travel times. However, the median predicted increase is positive for each of these routes, with an average of 6 min, suggesting that there may be some measurable increase in travel time for drivers that use the viaduct as a core component of their commute.  相似文献   
74.
Due to their complementary characteristics, Global Positioning System (GPS) is integrated with standalone navigation devices like odometers and inertial measurement units (IMU). Recently, intensive research has focused on utilizing Micro-Electro-Mechanical-System (MEMS) grade inertial sensors in the integration because of their low-cost. In this study, a low cost reduced inertial sensor system (RISS) is considered. It consists of a MEMS-grade gyroscope and the vehicle built-in odometer. The system works together with GPS to provide 2D navigation for land vehicles. With adequate accuracy, Kalman filter (KF) is the commonly used estimation technique to achieve the data fusion of GPS and inertial sensors in case of high-end IMUs. However, due to the inherent error characteristics of MEMS grade devices, MEMS-based RISS suffers from the non-stationary stochastic sensor errors and nonlinear inertial errors, which cannot be handled by KF and its linear error models. To overcome the problem, Fast Orthogonal Search (FOS), a nonlinear system identification technique, is suggested for modeling the higher order RISS errors. As a general-purpose numerical method, FOS algorithm has the ability to figure out the system nonlinearity efficiently with a tolerance of arbitrary stochastic system noise. Even using online short-term training data, this method is still able to build an accurate nonlinear model that predicts the system dynamics. Motivated by the above merits, an augmented KF/FOS module is proposed by cascading FOS algorithm to a traditional KF structure. By estimating and reducing both linear and nonlinear RISS errors, the proposed method is supposed to offer substantial enhancement on the positioning accuracy of MEMS-based RISS during GPS outages. In order to examine the effectiveness of the proposed technique, the KF/FOS module is applied on the low cost RISS together with GPS in a land vehicle for several road test trajectories. The performance of the proposed method is compared to KF-only solution, both assessed with respect to a reference offered by a high-end solution. The experimental results confirm that KF/FOS module outperforms KF-only method. The results also show the applicability of the proposed method for real-time vehicle applications.  相似文献   
75.
This paper investigates the role of location factors in task and time allocation at the household level. It is hypothesized that, if time constraints are less binding as a result of living in an urban area or owning more cars, spouses engage more often and longer in out-of-home activities and schedule their activities more independently. The hypotheses are tested with logistic and Cox regression models of activity participation and time allocation on a data set collected in the Amsterdam–Utrecht region in the Netherlands. Results suggest that the hypotheses are supported with respect to specific household activity scheduling decisions.  相似文献   
76.
前照灯分为可拆式、半封闭式和封闭式3种。其中封闭式前照灯(即真空灯)其反射镜和前透镜是用玻璃制成一体,形成灯泡,内部充以惰性气体,灯丝焊在反射镜底座上。封闭式前照灯的优点是,可避免反射镜被污染及遭受大气的影响。其缺点是,当灯丝烧坏后,需要更换整个总成。1前照灯的使用要点 汽车前照灯应保证夜间行车时有明亮而均匀的照明,使驾驶员能辨明车前100 m左右道路上的任何障碍物;还应具有防眩目装置,以免夜间两车交会时使对方驾驶员目眩而发生事故。前照灯的使用要点有: a.应保持前照灯有良好的密封性,以防灰尘和潮…  相似文献   
77.
简要介绍了CA142载货车所装用的空压机的结构和性能参数,详细分析了空压机的泵气和卸荷两工作过程,认为在使用中应注意管路中调压阀和安全空的压力值和空滤器的清洗问题。同时提出了对空压机卸荷失灵,空压机泵气不足,空压机温度高,空压机有异响等故障的排除方法。  相似文献   
78.
学习澳大利亚职教先进理念 提升我国高职教育整体水平   总被引:1,自引:0,他引:1  
文章从政府投入、行业主导、技能培养、师资队伍建设、教学改革等方面对澳大利亚和我国高职教育进行了比较研究,指出了我国高职教育存在的问题,并在此基础上探讨了改革我国高职教育的途径。  相似文献   
79.
铁路专用线是衔接国铁路网与工业企业(厂、矿、港)的重要纽带,其接轨方案直接影响专用线运输效率效益。结合安徽丰原集团地理位置及周边既有铁路车站分布,分析连城站接轨和固镇站接轨2个方案。在综合比选确定连城站接轨方案的基础上,提出连城站东侧接轨方案与西侧接轨方案。经过比较分析线路长度、工程投资、车站改造条件、运输组织、城市规划等因素,确定采用连城站东侧接轨方案,为铁路专用线接轨站设置提供借鉴。  相似文献   
80.
Urban rail transit enhances accessibility of the communities it serves and often contributes to the value of local real properties. A small number of studies have gone beyond the traditional cross-sectional hedonic analysis to use repeat-sales data in the US for more robust estimation of rail transit’s impact on property value. While the empirical literature generally supports the positive capitalization of rail transit in home value, it has produced widely varied estimates and failed to incorporate the theoretical insight that more elastic housing supply would reduce the extent of local amenities’ capitalization in home value. Observing Beijing’s rapid expansion of subway lines during the late 2000s, this study uses repeat rental transactions from 2005 to 2011 to investigate how home value reacts to the change in the home’s distance to nearest subway station. Repeat-rentals estimates suggest a rent-distance elasticity of −0.02, 70% below the cross-sectional hedonic estimate. Moreover, using the unique history of state-owned enterprise relocations as instrument for intra-city variation in land supply, we find that the capitalization of subway proximity in home value is weaker where land supply is more elastic. Our findings support the significant bias caused by omitted variables in the hedonic estimates and confirm housing supply’s role in explaining the intra-city spatial variation in estimates.  相似文献   
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