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111.
文章针对服刑人员行为矫正评估中测试指标多、计算量大导致的不易观测问题,提出了采用因子分析和聚类分析法对不同测题进行有分类抽题和组题,利用聚类分析对测评成绩的合理归类,进而对数据进行综合分析的评定方法,并以图表方式实例化展示了分析结果。  相似文献   
112.
河池至百色高速公路属于典型的山岭区公路,地形、地质条件复杂,桥隧比例大,路线走廊带选择对于控制工程规模、降低造价具有重要意义。文章介绍了该路长老至平坎段路线方案比选研究情况,以期为类似工程的路线设计工作提供借鉴。  相似文献   
113.
6502电气集中以及计算机联锁是保证站内运输作业安全,提高作业效率的安全设备,三点检查方法是进路内轨道电路区段正常解锁的依据条件之一。从信号安全角度对三点检查的应用进行了分析思考,重点阐述三点检查在既有信号领域的运用范围及其特点,进而在区间自动闭塞模式基础上引入区间进路的理念,从而把区间纳入联锁安全保障之中,并提出建议。  相似文献   
114.
This paper presents the historical and cultural background relating to road improvement and road safety characteristics in Kenya, a developing country in East Africa. Some who come from low-developed areas of developing countries often take time to comprehend the modern transportation infrastructure, especially roads, and have difficulty assimilating and customizing the same to their culturally tailored modes.This paper discusses two case studies: one on the socio-economic impact following improvements to a 50-km, high-class, high-traffic-volume road and the other on the monitoring and evaluation of road safety aspects along the Northern Corridor in Kenya also following major road improvements.The road improvements to the Nairobi-Thika Highway (a trunk road) have attracted many investors along the highway corridor. The high-speed road has also brought with it the unfortunate consequence of speeding vehicles colliding with pedestrians crossing the road at undesignated locations.The Northern Corridor, the transportation corridor that links the Great Lakes Countries of the Democratic Republic of Congo, Burundi, Rwanda, and Uganda from the port of Mombasa in Kenya, has had high accident rates for a considerable amount of time. The results of monitoring and evaluation exercises on the Northern Corridor have shown that drivers are the major contributors in causing accidents, with a component ratio of 49.4%; pedestrians are next at 21.7%. Data also shows that 24% of the accidents along the Northern Corridor are fatal, which is of major concern. The study additionally indicated that the majority of road users have not been exposed to education or training on road safety.This paper presents a number of recommendations arising from the road safety study regarding possible improvements in aspects of road safety along the corridor and potential applications of those changes to other roads in general. For example, there are recommendations related to the geometric design of the road, driver training and behavior, vehicle maintenance, and the need to enhance road safety through the utilization of road safety parks where road users can undergo training and drills on road safety aspects.In conclusion, we argue that the rehabilitation of the Northern Corridor from Mombasa on the Kenyan coast to the border with Uganda has led to significant road safety improvement.  相似文献   
115.
南水北调中线工程潮河段隧洞盾构选型设计研究   总被引:1,自引:0,他引:1       下载免费PDF全文
针对南水北调中线总干渠潮河段隧洞工程的水文地质和工程地质条件,结合隧道结构、管片形式和施工特点,从土压平衡盾构和泥水平衡盾构的掘进机理及对不同地层的适应性进行分析。根据2种盾构的工作状况、出渣设备、施工场地、经济性、环境影响等多方面特点,对土压平衡盾构和泥水平衡盾构进行综合比较,提出适用于潮河段隧洞工程施工用的盾构机型。  相似文献   
116.
Wistar孕鼠24只,随机等分为3组,于妊娠5天~18天分别接受100dB(A)、85dB(A)和<50dB(A)(对照组)的稳态噪声刺激,观察仔代出生后生长发育情况。结果:100dB(A)组仔鼠出生体重、身长显著低于对照组仔鼠,嗅觉、神经肌肉发育延迟,紧张性情感较对照组高,学习记忆能力低于对照组仔鼠。提示:100dB(A)的孕期噪声暴露,可对仔鼠行为发育产生一定影响。  相似文献   
117.
Electric travelling appears to dominate the transport sector in the near future due to the needed transition from internal combustion vehicles (ICV) towards Electric Vehicles (EV) to tackle urban pollution. Given this trend, investigation of the EV drivers’ travel behaviour is of great importance to stakeholders including planners and policymakers, for example in order to locate charging stations. This research explores the Battery Electric Vehicle (BEV) drivers route choice and charging preferences through a Stated Preference (SP) survey. Collecting data from 505 EV drivers in the Netherlands, we report the results of estimating a Mixed Logit (ML) model for those choices. Respondents were requested to choose a route among six alternatives: freeways, arterial ways, and local streets with and without fast charging. Our findings suggest that the classic route attributes (travel time and travel cost), vehicle-related variables (state-of-charge at the origin and destination) and charging characteristics (availability of a slow charging point at the destination, fast charging duration, waiting time in the queue of a fast-charging station) can influence the BEV drivers route choice and charging behaviour significantly. When the state-of-charge (SOC) at the origin is high and a slow charger at the destination is available, routes without fast charging are likely to be preferred. Moreover, local streets (associated with slow speeds and less energy consumption) could be preferred if the SOC at the destination is expected to be low while arterial ways might be selected when a driver must recharge his/her car during the trip via fast charging.  相似文献   
118.
一种高速铁路衔接站点灭灯进路联锁软件实现方法   总被引:1,自引:1,他引:0  
高速铁路信号机的显示采用了新的技术标准,信号机的常态为灭灯,其联锁逻辑与普速铁路有较大不同。尤其在衔接站,逻辑更为复杂。基于站场图形网络的软件架构,采用模块和消息方法,对信号机点灭灯办理进路的联锁软件进行设计,并分析通过进路和组合长进路的典型情况。该方法适用于衔接站常态灭灯和点灯信号机混合布置的情况。对于信号显示,采用基于布尔表达式方法构建显示逻辑并通过另一份软件和数据进行校核。从风险点和防御措施的角度分析软件安全性,认为采用的方法符合产品安全性要求,适合于工程推广应用。  相似文献   
119.
合理科学的线路走向会降低工程投资、提高运输效率,使线路在路网中发挥最佳的作用。为了研究线路走向合理科学的决策方法,通过分析影响线路走向的各种因素,提取主影响因子及属性特征,利用Arc GIS的空间分析、数据处理,实现属性单元的指标值量化。根据空间多维度相似的相似度计算方法,通过空间相似理论和提取出的主影响因子,构建设计线路方案决策模型,实现基于空间相似理论的线路走向决策。并以兰州张掖城际铁路选线为例进行实证分析,得到合理的线路走向推荐方案。结果表明,该方法可应用到线路走向决策中,可为以后线路走向的选定提供参考。  相似文献   
120.
本文论述了下坡道延续进路与区间列车运行方向的安全问题,同时分析了利弊。  相似文献   
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