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391.
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
392.
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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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
395.
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
396.
Transport systems in real cities are complex with many modes of transport sharing and competing for limited road space. This work intends to understand how space distributions for modes and interactions among modes affect network traffic performance. While the connection between performance of transport systems and general land allocation is the subject of extensive research, space allocation for interacting modes of transport is an open research question. Quantifying the impact of road space distribution on the performance of a congested multimodal transport system with a dynamic aggregated model remains a challenge. In this paper, a multimodal macroscopic fundamental diagram (MFD) is developed to represent the traffic dynamics of a multimodal transport system. Optimization is performed with the objective of minimizing the total passenger hours traveled (PHT) to serve the total demand by redistributing road space among modes. Pricing strategies are also investigated to provide a higher demand shift to more efficient modes. We find by an application to a bi-modal two-region city that (i) the proposed model captures the operational characteristics of each mode, and (ii) optimal dynamic space distribution strategies can be developed. In practice, the approach can serve as a physical dynamic model to inform space distribution strategies for policy makers with different goals of mobility. 相似文献
397.
基于多目标粒子群算法的船舶主尺度优化设计研究 总被引:1,自引:0,他引:1
粒子群优化是一种新兴的进化计算技术。文章基于多目标粒子群优化算法讨论了船舶主尺度论证中的多目标优化和决策问题。对于多目标优化问题,采用基于Pareto占优方法的多目标粒子群算法得到最优解,然后采用距离理想解最近的方法对这些Pareto最优解给出排序。应用文中给出的两个阶段求解方法,对散装货船概念设计阶段主尺度确定的问题进行了分析。结果表明,综合多目标粒子群优化和决策技术,能够迅速、客观地选择合理的船舶主尺度,可以给设计人员提供更多的选择。这种综合方法也能够广泛用于船舶其他设计领域。 相似文献
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