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331.
The lack of a proper integration of strategic Air Traffic Management decision support tools with tactical Air Traffic Control interventions usually generates a negative impact on the Reference Business Trajectory adherence, and in consequence affects the potential of the Trajectory-Based Operations framework. In this paper, a new mechanism relaying on Reference Business Trajectories as a source of data to reduce the amount of Air Traffic Controller interventions at the tactical level while preserving Air Traffic Flow Management planned operations is presented. Artificial Intelligence can enable Constraint Programming as it is a powerful paradigm for solving complex, combinatorial search problems. The proposed methodology takes advantage of Constraint Programming and fosters adherence of Airspace User’s trajectory preferences by identifying tight interdependencies between trajectories and introducing a new mechanism to improve the aircraft separation at concurrence events considering time uncertainty. The underlying philosophy is to capitalize present degrees of freedom between layered Air Traffic Management planning tools, when sequencing departures at the airports by considering the benefits of small time stamp changes in the assigned Calculated Take-Off Time departures and to enhance Trajectory-Based Operations concepts. 相似文献
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334.
遗传算法(Genetic Algorithm,GA)是一种基于自然群体遗传演化机制的高效优化算法,它能模拟自然界生物进化过程,依据适者生存,优胜劣汰的进化规则,采用人工进化的方式对目标群体进行遗传操作,不断得到更优群体。文章根据遗传算法基本思路,在MATLAB/Simulink中搭建了基于遗传算法的车辆半主动悬架参数优化模型,利用该算法对半主动悬架控制系统参数进行了优化,并对优化结果进行了仿真分析,结果表明,优化后车辆簧载质量加速度均方根值降低31.1%、悬架动挠度均方根值降低11.2%、轮胎动载荷均方根值降低7.1%,车辆平顺性得到提升。 相似文献
335.
An optimization technique was used to generate a wing-in-ground-effect (WIG) configuration which can achieve the maximum lift
and satisfy the height stability criteria within the design constraints. For the analysis of the aerodynamic coefficients,
the vortex lattice method (VLM) was applied with the inviscid and potential flow approximations. The sequential quadratic
programming (SQP) method, which is a nonlinear optimization method, was employed as an optimization tool. The lift and moment
coefficients, including the stability analysis computed by VLM, were compared with the experimental results of a medium-sized
WIG, and a good correlation was found between them. In addition, the optimization tool was validated by finding the optimal
position of the side wing attached on the WIG craft. Then, various optimum examples are shown, with generation of the wing
section, the determination of the planform configuration, the aspect ratio, and the position of the tail wing within the design
constraints. It was shown that the present optimization tool can be used effectively for the optimal design of a WIG craft. 相似文献
336.
B. -L. Choi D. -H. Choi J. Min K. Jeon J. Park S. Choi J. -M. Ko 《International Journal of Automotive Technology》2009,10(1):49-54
This research proposes an automatic torsion beam axle optimization process with a multidisciplinary approach and generates
the optimal torsion design parameters, such as thickness and shape. In order to construct an automatic analysis process, multidisciplinary
analysis models, such as modal analysis, roll mode dynamic analysis, and fatigue analysis, were applied in batch mode. To
understand the design space, a parametric study using the torsion beam thickness and shape was performed. Considering roll
durability and K&C characteristics, the torsion beam axle could be optimized. For the automated design process, a PIDO tool
called PIAnO was used. In conclusion, a reduction in the computer-aided simulation time was achieved, and the durability and
K&C characteristics of the torsion beam were enhanced by optimizing the thickness and shape. 相似文献
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338.
Efficient Transit Schedule Design of timing points: A comparison of Ant Colony and Genetic Algorithms 总被引:1,自引:0,他引:1
Ehsan Mazloumi Mahmoud MesbahAvi Ceder Sara MoridpourGraham Currie 《Transportation Research Part B: Methodological》2012,46(1):217-234
This work defines Transit Schedule Design (TSD) as an optimization problem to construct the transit schedule with the decision variables of the location of timing points and the amount of slack time associated with each timing point. Two heuristic procedures, Ant Colony and Genetic Algorithms, are developed for constructing optimal schedules for a fixed bus route. The paper presents a comparison of the fundamental features of the two algorithms. They are then calibrated based on data generated from micro-simulation of a bus route in Melbourne, Australia, to give rise to (near) optimal schedule designs. The algorithms are compared in terms of their accuracy and efficiency in providing the minimum cost solution. Although both procedures prove the ability to find the optimal solution, the Ant Colony procedure demonstrates a higher efficiency by evaluating less schedule designs to arrive at a ‘good’ solution. Potential benefits of the developed algorithms in bus route planning are also discussed. 相似文献
339.
文章在总结已有研究成果的基础上,分析影响深基坑的支撑体系参数,并根据优化分析的原则,提出模糊神经网络的优化分析方法,确定了深基坑支撑体系优化分析步骤。 相似文献
340.
The purpose of this article is to present an optimization model to plan the deployment strategy for hydrogen refuelling stations in a city when Origin–Destination (OD) data are not available. This model considers two objectives: to maximize the traffic covered by the selected hydrogen refuelling stations and minimize the average distance of the city’s inhabitants to the nearest hydrogen refuelling station. As OD data are assumed to be unavailable, the clustering of stations in the highest traffic zones is prevented by a new constraint that takes into account information on the distribution of existing conventional refuelling stations. This model is applied to Seville, a city in Southern Spain of about 140 km2 with a population of around 700,000. This application uses the results of a survey of more than 200 Sevillian drivers on their current refuelling tendencies, their willingness to use alternative fuel vehicles and their minimum requirements (regarding maximum distance to be travelled to refuel and number of stations in the city) when establishing a network of alternative refuelling stations. 相似文献