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231.
ABSTRACT

In the contemporary port business environment, port resilience is of paramount importance for supply chain continuity. A result of the increased integration of ports into supply chains is ports’ potential to supply chain disruptions. This paper introduces a PSCD management model that incorporates the application of risk management, business continuity management, and quality management theories with the purpose of increasing port resilience such that supply chain continuity is enhanced. To validate this model, primary data were collected from samples of port operators and port authorities and analyzed using structural equation modeling with AMOS 22.0. The results indicate that managing PSCD using the management model contributes positively to the identification of internal and external opportunities and through that to port’s resilience of internal operations. This, in turn, positively influences port’s financial health and market reputation. The management model has several managerial and academic implications as it offers meaningful insights on policy development as well as theory building.  相似文献   
232.
233.
In the real world, planned aircraft maintenance schedules are often affected by incidents. Airlines may thus need to adjust their aircraft maintenance schedules following the incidents that occur during routine operations. In tradition, such aircraft maintenance schedule adjustment has been performed manually, a process which is neither effective nor efficient, especially when the problem scale is large. In this study, an aircraft maintenance schedule adjustment model is developed, with the objective of minimizing the total system cost, subject to the related operating constraints. The model is formulated as a zero-one integer program and is solved using a mathematical programing solver. The effectiveness of the model is evaluated by application to a case study using data from an aircraft maintenance center in Taiwan. The test results show the proposed model, as well as the scheduling rules abstracted from the results are useful for the decision maker to adjust good maintenance schedules.  相似文献   
234.
Abstract

This paper reviews the main modules of an integrated system for incident management in real-time, -sim. A core to such a system is a microscopic simulator with extended abilities to model the temporal and spatial evolution of specified non-recurrent traffic conditions. The paper reviews the mathematical formulation of the car-following and lane-changing modules. The model is validated using a simulation-based approach. Concluding comments on the general validation process of the model are provided. The paper finally presents a sample of the accident patterns replicated by the model together with their implications for real world validation.  相似文献   
235.
基于UC-win/Road的城市高架路建模及应用   总被引:3,自引:0,他引:3  
随着城市的飞速发展和道路基础设施的完善,城市高架路作为主要城市快速路之一,已成为国内外城市解决交通问题的重要手段之一。利用UC-win/Road软件及其模拟器可以实现城市高架路的模拟仿真。以南京市宁溧高架为例,设计资料为平、纵、横参数,在UC-win/Road平台上进行建模并实现模拟驾驶,最后对其应用前景作出展望。  相似文献   
236.
为改善城市中心区的交通拥堵,以国内城市中心区区域路网为研究对象,以路网车辆整体延误时间最短为优化目标,拥堵收费价格为决策变量,路网饱和度和信号配时为约束条件,建立了拥堵定价优化模型,并给出了基于VISSIM软件的仿真求解方法和步骤.实例仿真结果表明:在城市中心区区域路网采用该定价模型可以找到最优定价及合理的信号配时方案;计算机仿真方法可大幅度降低模型求解难度,并可直观地为交通管理部门制订拥堵定价方案提供理论依据.  相似文献   
237.
An experimental investigation of irregular wave forces on quasi-ellipse caisson structures is presented. Irregular waves were generated based on the Jonswap spectrum with two significant wave heights, and the spectrum peak periods range from 1.19 s to 1.81 s. Incident wave directions relative to the centre line of the multiple caissons are from 0° to 22.5°. The spacing between caissons ranges from 2 to 3 times that of the width of the caisson. The effects of these parameters on the wave forces of both the perforated and non-perforated caissons were compared and analyzed. It was found that the perforated caisson can reduce wave forces, especially in the transverse direction. Furthermore, the relative interval and incident wave direction have significant effects on the wave forces in the case of multiple caissons.  相似文献   
238.
舰船动力系统模块化建模方法   总被引:1,自引:0,他引:1  
在舰船动力系统仿真平台的研究中,建立的系统模型应能够满足实时仿真的要求,同时具有通用性,以提高仿真模型的重复利用率。以某型舰船动力系统为例,研究模块的分类、模块的分解处理等模块化建模方法,建立其模型库并进行仿真验证。该方法克服了传统建模法得到的模型可移植性与独立性较差的缺点,提高了模型的可重用性。  相似文献   
239.
为提高舰载反鱼雷鱼雷(ATT)对抗鱼雷的作战效率,研究ATT在多种方案下拦截鱼雷的问题。针对以往ATT二维对抗态势模型的不足,建立三维立体空间下的ATT运动学模型、鱼雷运动模型、ATT/鱼雷自导模型以及误差模型,运用MATLAB工具对ATT的对抗过程进行推演,并采用蒙特卡洛法定量分析ATT发射距离对不同拦截方案下拦截概率的影响。仿真结果表明,该模型可以用于舰载ATT对抗方案的定量评价。  相似文献   
240.
于鹏 《交通标准化》2014,(15):234-239
在分析当前公路设计流程存在的问题的基础上,提出基于ESIA方法的流程优化方案,可为解决公路勘察设计中项目管理的难题提供一定的参考与借鉴.  相似文献   
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