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871.
ABSTRACT Marketing policies have gained more importance in container shipping as the industry experiences challenges arising from commoditization. Market segmentation is fundamental to marketing policies, yet it needs a detailed analysis in container shipping. Accordingly, this paper aims to explore homogenous customer groups in container shipping by conducting a segmentation analysis, which can help container lines apply more efficient marketing policies. A survey study is conducted on 356 shippers in Turkey. The study develops five reliable and valid selection criteria factors and applies cluster analysis based on the selection criteria factors. The cluster analysis produces a total of six benefit segments which are differentiable. The segments are significantly identified by the demographic characteristics of shippers. The paper suggests several implications for the marketing policies of container lines. 相似文献
872.
既有研究对城市轨道交通客流与土地利用依赖关系的分析较为充分,然而针对建成环境
特征对客流影响的研究仍不够细致。本文采用开发强度、混合用地、慢行交通环境、公共交通可
达性和可获得性等变量刻画城市轨道交通TOD(Transit-Oriented Development, TOD)建成环境的
5D特征,基于多源地理大数据提出其计算方法,并利用多尺度地理加权回归研究TOD建成环境
对早高峰出站客流影响的空间特征。针对北京的案例研究表明:TOD建成环境特征的空间分布
具有显著空间异质性,多尺度地理加权回归能够刻画客流与上述特征变量依赖关系的空间异质
性及其影响尺度,其估计结果更为可靠。TOD建成环境对早高峰出站客流的影响效果呈现显著
的区域差异特征。两者关系的空间非平稳性表明:不同区域车站的TOD开发应采取差异化发展
政策。郊区车站更适合强调规模和强度的发展策略,而中心城区车站则较难通过进一步提高规
模和强度以改善客流效果,而应更强调发展的质量。 相似文献
873.
874.
针对网联车辆与普通车辆构成的异质交通流,考虑网联车辆车对车(V2V)、车对基础设施(V2I)不同通信技术,研究复杂异质交通流稳定性.基于李雅普诺夫理论,分析对比不同通信技术下网联车辆与普通车辆构成的异质交通流稳定性;基于V2V、V2V/V2I的网联车辆和普通车辆以不同比例混合时,进行异质交通流稳定性判别及稳定域解析.通过数值仿真,验证理论解析的正确性.研究结果表明,基于V2V/V2I的网联车辆比基于V2V的网联车辆混入对异质交通流稳定性改善效果更显著.基于V2V、V2V/V2I的网联车辆同时汇入普通车辆交通流的情况下,当基于V2V的网联车辆比例较低时,不会明显提高异质交通流稳定性;而基于 V2V/V2I的网联车辆即使在低比例时,也会显著改善交通流稳定性;且基于V2V网联车辆比例较低时,平衡态临界速度值随着基于V2V/V2I网联车辆的比例增加近似呈线性减小. 相似文献
875.
876.
This study introduces a new CONnectivity ROBustness model (CONROB) to assess vehicle-to-vehicle communication in connected vehicle (CV) environments. CONROB is based on Newton’s universal law of gravitation and accounts for multiple factors affecting the connectivity in CV environments such as market penetration, wireless transmission range, spatial distribution of vehicles relative to each other, the spatial propagation of the wireless signal, and traffic density. The proposed methodology for the connectivity robustness calculation in CONROB accounts for the Link Expiration Time (LET) and the Route Expiration Time (RET) that are reflected in the stability of links between each two adjacent vehicles and the expiration time of communication routes between vehicles. Using a 117 sq-km (45-square mile) network in Washington County, located west of Portland city, Oregon, a microscopic simulation model (VISSIM) was built to verify CONROB model. A total of 45 scenarios were simulated for different traffic densities generated from five different traffic demand levels, three levels of market penetration (5%, 15%, and 25%), and three transmission range values [76 (250), 152 (500), and 305 (1000) m (ft)]. The simulation results show that the overall robustness increases as the market penetration increases, given the same transmission range, and relative traffic density. Similarly, the overall connectivity robustness increases as the relative traffic density increases for the same market penetration. More so, the connectivity robustness becomes more sensitive to the relative traffic density at higher values of transmission range and market penetration. Multiple regression analysis was conducted to show the significant effect of relative traffic density, transmission range, and market penetration on the robustness measure. The results of the study provide an evidence of the ability of the model to capture the effect of the different factors on the connectivity between vehicles, which provides a viable tool for assessing CV environments. 相似文献
877.
In order to realise sustainable urban transport, it is necessary to combine different kinds of decision-making, including vision-led, plan-led and consensus-led approaches. In this paper, a cross-assessment model that supports both vision-led and consensus-led approaches is proposed as an analytical tool for developing sustainable urban transport and land use strategies for a low-carbon society. It is applied to an impact analysis of public transport and land use strategies in 2030 for all of Japan's 269 urban areas, with outcomes – including the financial balance of public transport operation, user benefits, and CO2 emissions reduction – compared by strategy and urban area. 相似文献
878.
879.
带舭龙骨柱体的横摇阻尼的粘性流计算 总被引:1,自引:0,他引:1
文章用RANSE求解器计算在自由面上带舭龙骨二维柱体的横摇水动力系数(附加惯量和阻尼).采用有限体积法(VOF)和两相流技术在时间域内求解柱体横摇强迫振荡所扰动的带自由面粘性流场.由柱体所受到的横摇水动力矩的时间历程导出横摇水动力系数.文中所给算例与已公开发表的试验结果吻合令人满意. 相似文献
880.