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51.
Choices of travel mode and trip chain as well as their interplays have long drawn the interests of researchers. However, few studies have examined the differences in the travel behaviors between holidays and weekdays. This paper compares the choice of travel mode and trip chain between holidays and weekdays tours using travel survey data from Beijing, China. Nested Logit (NL) models with alternative nesting structures are estimated to analyze the decision process of travelers. Results show that there are at least three differences between commuting-based tours on weekdays and non-commuting tours on holidays. First, the decision structures in weekday and holiday tours are opposite. In weekday tours people prefer to decide on trip chain pattern prior to choosing travel mode, whereas in holiday tours travel mode is chosen first. Second, holiday tours show stronger dependency on cars than weekday tours. Third, travelers on holidays are more sensitive to changes in tour time than to the changes in tour cost, while commuters on weekdays are more sensitive to tour cost. Findings are helpful for improving travel activity modeling and designing differential transportation system management strategies for weekdays and holidays.  相似文献   
52.
Ramp metering has been proven as an effective freeway management strategy; however, the impact of ramp metering on drivers' acceleration behavior has not been fully investigated. A better understanding of acceleration behavior changes with ramp metering is critical to the adequate design of ramp metering facilities. In this study, drivers' speed and acceleration data were collected at two representative metered ramps in Los Angeles, California. The speed and acceleration profiles under meter-on and meter-off scenarios were compared. Statistical results demonstrated that ramp metering affects drivers' acceleration behavior at ramp acceleration lane. It was found that at the metered ramp with short existing acceleration length, the average acceleration rate from ramp meter stop bar to 500 ft downstream under meter-on scenario (4.72 ft./s2) is approximately 40% higher than when meter-off (3.18 ft./s2). The design of acceleration lane length for metered on-ramps should therefore take into account the potential impacts of ramp metering on driver acceleration behavior.  相似文献   
53.
为稳步增强汽车驾驶的安全性,减少安全事故的发生,驾驶人员除了需要具备足够的应急应变能力之外,还需要做好安全行为习惯养成工作,形成良好的驾驶习惯。文章以汽车驾驶员不安全行为作出研究对象,在明确不安全行为表现的基础上,深刻分析影响汽车驾驶人员不安全行为的因素,在此基础上,制定合理的应对策略,旨在引导驾驶人员形成安全行为,以不断提升驾驶员的驾驶能力。  相似文献   
54.
为了解儿童心理发育状况及其影响因素 ,应用 Achenbach′s儿童行为量表 ,测查了西安市 86 2名小学生。结果显示小学生行为问题检出率为 14.7%。多因素分析表明 ,影响小学生行为发育的因素主要有父母婚姻状况不佳、父亲健康状况差、不良的教育方式及不适当的期望等。提示小学生中存在的行为问题较为严重 ,在儿保及学校卫生工作中应重视加强精神卫生保健。  相似文献   
55.
在认知心理学理论背景下,分析了乘客进入地铁地下空间的心理行为及感受。通过地铁导视系统与认知地图的搭建,剖析完善的地铁空间认知元素,并以此为设计对象,对地铁导视系统中乘客方向感缺失等问题作出一些具体分析与优化。  相似文献   
56.
This study aimed to investigate Thai motorcyclists' traffic risk behavior and their perceptions of it, information of value in the design and implementation of public health policies and campaigns for the reduction of road injuries. Data was collected by a self-administered questionnaire completed by 399 motorcyclists in Muang Krabi district, Krabi province, Thailand. The questionnaire focused on the respondents' perceptions of general traffic risks and the specific risks at 3 identified hazardous sites. The results of the survey indicated that the correct fastening of helmet straps had a relationship with responsible traffic risk perceptions.  相似文献   
57.
对于钢—混凝土组合结构而言,其两者的有效结合和共同受力是关键。以某座刚架系杆拱桥钢—混凝土接头为对象进行了研究,作为整个桥梁的关键构造,其计算理论是否符合实际及合理显得尤为重要。文章采用解析的方法,考虑了基于三角形反力分布和矩形反力分布两种埋入式接头模式,并在矩形反力分布模式中考虑了钢—混凝土粘结力的影响。将两种计算模式的结果及是否考虑钢—混凝土粘结力计算的结果进行了比较。结果表明:具有类似工程背景的混合拱桥钢—混凝土接头可以采用设结合段的埋入式接头理论进行设计与分析,是否考虑钢—混凝土粘结力对计算结果有较大的影响。  相似文献   
58.
The effect of uniform current on the generation of flexural gravity waves resulting from initial disturbances at a point was analyzed in two dimensions. The problem was formulated as an initial boundary value problem under the assumptions of the linearized theory of water waves. By direct application of the Laplace transform and then the Fourier transform, explicit expressions for the velocity potential and free surface elevation were obtained in integral forms; these were evaluated asymptotically for large distances and times by the application of the method of the stationary phase to obtain the far field behavior of the surface elevations in specific cases. Simple numerical computations were performed to illustrate the effect of uniform current on the surface elevation, wavelength, phase velocity, and group velocity of the flexural gravity waves and on the far field behavior of the progressive waves in two different cases, namely, when there is an initial depression concentrated at the origin and an initial impulse concentrated at the origin.  相似文献   
59.
ByusingCBCL(ChildBehaviorChecklist)ofXi′annorm,thechildren'sbehaviorproblemsinXi′anhavebeeninvestigatedandcomparedwiththeresultsobtainedbefore1993,thepositiveresultsprovidescientificbasisfordiagnosisandreferenceforteachers.MATERIALSANDMETHODSThepupil…  相似文献   
60.
采用带间隙双回路反向电流(ODIG)感应器作为热源,基于ANSYS多物理场耦合数值模拟方法,结合感应器及周围空气动态移动方法,建立移动式电磁-热交互耦合数值模拟模型。将获得的瞬态温度作为载荷,进行热-弹塑性数值分析,研究船用钢板移动电磁感应加热温度分布和变形分布。分析不同工艺参数(感应器与钢板间隙g、钢板厚度H、电流频率F、电流峰值I_(peak)和移动速度v)对热成形(最高温度T_(um)、宽度b和厚度h)和变形(横向收缩δ_z和横向角变形θ_z)特性的影响。结果表明:温度云图为带预热的双椭圆外形;影响热成形特性的主要因素为I_(peak)、v和g;影响变形最主要的因素是I_(peak)和H。  相似文献   
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