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61.
For centuries, the maritime industry has been a recognised place in society dominated solely by men, and even though there were women involved, they were mostly on the periphery. This research aims to fill the gap of women’s career development in this field, by investigating the relationships among the degree of organisational socialisation, women’s workplace culture, and the career development of women in the maritime workplace. The analyses are conducted with the structural equation model with 202 valid questionnaires. The results indicated that women’s workplace culture has a significantly negative relationship with the degree of organisational socialisation, and then in turn, it has a significantly positive relationship with women’s career development in the maritime industry. Finally, the results also indicate that the mediating effect of organisational socialisation existed between women’s workplace culture and women’s career development. According to the empirical analysis, this study makes conclusions as well as suggestions for the maritime enterprises as the reference for human resource management.  相似文献   
62.
In this paper, a novel mesoscopic multilane model is proposed to enable simultaneous simulation of mandatory and discretionary lane-changing behaviors to realistically capture multilane traffic dynamics. The model considers lane specific fundamental diagrams to simulate dynamic heterogeneous lane flow distributions on expressways. Moreover, different priority levels are identified according to different lane-changing motivations and the corresponding levels of urgency. Then, an algorithm is proposed to estimate the dynamic mandatory and discretionary lane-changing demands. Finally, the lane flow propagation is defined by the reaction law of the demand–supply functions, which can be regarded as an extension of the Incremental-Transfer and/or Priority Incremental-Transfer principles. The proposed mesoscopic multilane cell transmission model is calibrated and validated on a complex weaving section of the State Route 241 freeway in Orange County, California, showing both the positive and negative impact of lane changing maneuvers, e.g., balancing effect and capacity drop, respectively. Moreover, the empirical study verifies that the model requires no additional data other than the cell transmission model does. Thus, the proposed model can be deployed as a simple simulation tool for accessing dynamic mesoscopic multilane traffic state from data available to most management centers, and also the potential application in predicting the impact of traffic incident or lane control strategy.  相似文献   
63.
This paper estimates the price and income elasticities of air cargo demand and examines how they may change after the 2008 financial crisis. Using a set of time series data, we simultaneously estimate the aggregated demand and supply functions of air cargo at Hong Kong International Airport (HKIA). We find that during the entire sampling period of 2001–2013, the price elasticity for air cargo transport demand at HKIA ranges from −0.74 to −0.29, suggesting that air cargo demand in Hong Kong reacts negatively to price (as expected) but does not appear to be very sensitive to price. The income elasticity ranges from 0.29 to 1.47 and appears sensitive to seasonality adjustment approaches. However, in terms of the speed of changes, air cargo demand changes much faster than overall economy, indicating the presence of a pro-cyclical pattern of air cargo traffic with respect to the overall economy. Our analysis shows that air cargo demand becomes more sensitive to changes in both price and income after 2008.  相似文献   
64.
This paper illustrates a ride matching method for commuting trips based on clustering trajectories, and a modeling and simulation framework with ride-sharing behaviors to illustrate its potential impact. It proposes data mining solutions to reduce traffic demand and encourage more environment-friendly behaviors. The main contribution is a new data-driven ride-matching method, which tracks personal preferences of road choices and travel patterns to identify potential ride-sharing routes for carpool commuters. Compared with prevalent carpooling algorithms, which allow users to enter departure and destination information for on-demand trips, the proposed method focuses more on regular commuting trips. The potential effectiveness of the approach is evaluated using a traffic simulation-assignment framework with ride-sharing participation using the routes suggested by our algorithm. Two types of ride-sharing participation scenarios, with and without carpooling information, are considered. A case study with the Chicago tested is conducted to demonstrate the proposed framework’s ability to support better decision-making for carpool commuters. The results indicate that with ride-matching recommendations using shared vehicle trajectory data, carpool programs for commuters contribute to a less congested traffic state and environment-friendly travel patterns.  相似文献   
65.
Identifying the generators of paratransit trips by persons with disabilities is important to comprehend the current demand patterns and forecast future demand. Only a handful of studies have been conducted so far to identify the generators of paratransit trips and most focused on the home end of the trips. Given some of the inconsistencies in past studies and the scarcity of studies on the generators of trips away from home, this study attempts to identify the generators of paratransit trips beginning and ending at clients’ homes and away from home. It uses an extremely large dataset consisting of 1.91 million trips made by NJ TRANSIT’s Access Link clients, socioeconomic data from the American Community Survey, employment data from the Longitudinal Employer-Household Dynamics, and establishment data from Dun and Bradstreet. The analytical methods include an ordinary least squares model (OLS) and several spatial generalized linear mixed models (GLMM) to identify the characteristics of census block groups associated with Access Link trip generation at home and away from home, Geographic Information System (GIS) analysis to identify the types of establishments located in the immediate vicinity of drop-offs, and a multinomial logit model (MNL) to examine the relationship between the characteristics of the establishments in the vicinity of drop-offs and the characteristics of the dropped-off clients. Together, the various analyses provide useful insights about paratransit trip generators at the macro and micro levels. Some implications of the findings are discussed.  相似文献   
66.
针对掺混甲烷的乙烯层流火焰中的炭烟颗粒从形貌角度进行了研究,构建了具有相同当量比(2.07)、火焰温度、气体流速的层流预混乙烯火焰和掺混甲烷的乙烯火焰,并各自选取了3个高度进行热泳探针取样,采用TEM和AFM方法对各个工况的炭烟颗粒粒径分布、平均粒径、平均体积当量球径进行了对比。发现少量的甲烷掺混会令乙烯火焰中炭烟颗粒的尺寸变大,而当甲烷掺混量变多时该现象消失。而通过对颗粒的圆度、球度和分形维数计算和分析,发现即使是很小的颗粒也具有相似的不规则形状,这一现象广泛存在于各种火焰和各种大小的颗粒中,不受掺混比的影响,并且越大的颗粒结构越松散。  相似文献   
67.
文章基于机制设计理论的思想和框架,建立了农村金融市场上差异需求与分层供给行为选择的相关约束机制模型,分析了相关约束机制变量对农村金融供求行为选择的影响,从而提出了通过进一步改进和完善农村金融市场相关机制变量,促进我国农村金融供求者的匹配性行为选择,改善农村金融市场效率,加强金融对“三农”支持力度的政策建议。  相似文献   
68.
国家体育场作为北京奥运会的主会场成功地承担了开闭幕式和田径赛事任务。本文研究了其停车场车辆的交通疏散问题,制定了疏散方案。首先,分析了国家体育场停车场和泊位布局及车辆疏散的具体条件。其次,通过给定环境的场景和参数设定,对具体的奥运场馆停车场车辆的疏散方案进行了仿真和评价。最后,利用奥运会开幕式的车辆疏散实测数据进行了对比分析,在仿真中要员和贵宾车辆的总疏散时间为26min,而奥运会开幕式车辆疏散实测结果表明,全部要员、贵宾疏散完毕,共用时27min,从而验证了车辆疏散方案的准确性和实用性。  相似文献   
69.
交通需求管理(TDM)已成为保障奥运会期间突增交通需求的必要手段。本文在综合奥运会交通需求特性和对比往届奥运会TDM政策要点的基础上,从控制机动车使用、设置奥运专用道、公共交通保障、错时上下班及人性化保障等5个方面阐述TDM政策在北京奥运会中的应用,并从政策综合性、可操作性、接受程度及政策实施效果等4个角度对该TDM政策进行效果评价。数据表明:TDM政策的实施使道路交通流量下降22.5%,早高峰路网平均车速提高28.5%,122报警量下降,公共交通客运量大幅上升,且公共交通的出行比例达45%以上,有效均衡了交通需求,达到预期目标。  相似文献   
70.
在《机械(工程)制图》教学中,学生对基本体的变化及其在实际中的应用难以理解,文中介绍提高基本体教学效果的方法。  相似文献   
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