An adaptive compromise programming method for multi-objective path optimization

Network routing problems generally involve multiple objectives which may conflict one another. An effective way to solve such problems is to generate a set of Pareto-optimal solutions that is small enough to be handled by a decision maker and large enough to give an overview of all possible trade-offs among the conflicting objectives. To accomplish this, the present paper proposes an adaptive method based on compromise programming to assist decision makers in identifying Pareto-optimal paths, particularly for non-convex problems. This method can provide an unbiased approximation of the Pareto-optimal alternatives by adaptively changing the origin and direction of search in the objective space via the dynamic updating of the largest unexplored region till an appropriately structured Pareto front is captured. To demonstrate the efficacy of the proposed methodology, a case study is carried out for the transportation of dangerous goods in the road network of Hong Kong with the support of geographic information system. The experimental results confirm the effectiveness of the approach.     

Multi-criteria,personalized route planning using quantifier-guided ordered weighted averaging operators

This paper presents a generic model for using different decision strategies in multi-criteria, personalized route planning. Some researchers have considered user preferences in navigation systems. However, these prior studies typically employed a high tradeoff decision strategy, which used a weighted linear aggregation rule, and neglected other decision strategies. The proposed model integrates a pairwise comparison method and quantifier-guided ordered weighted averaging (OWA) aggregation operators to form a personalized route planning method that incorporates different decision strategies. The model can be used to calculate the impedance of each link regarding user preferences in terms of the route criteria, criteria importance and the selected decision strategy. Regarding the decision strategy, the calculated impedance lies between aggregations that use a logical “and” (which requires all the criteria to be satisfied) and a logical “or” (which requires at least one criterion to be satisfied). The calculated impedance also includes taking the average of the criteria scores. The model results in multiple alternative routes, which apply different decision strategies and provide users with the flexibility to select one of them en-route based on the real world situation. The model also defines the robust personalized route under different decision strategies. The influence of different decision strategies on the results are investigated in an illustrative example. This model is implemented in a web-based geographical information system (GIS) for Isfahan in Iran and verified in a tourist routing scenario. The results demonstrated, in real world situations, the validity of the route planning carried out in the model.     

无人直升机电力线路巡检自动航迹优化

针对目前关于无人直升机的航迹布设研究大多是讨论从起始点到目标点的,而复杂地形条件下的超低空电力线路巡检还没有一套完整的航迹布设方案这一问题,该文在充分考虑无人直升机性能、传感器参数、任务要求以及电力线路巡检过程中应注意问题的基础上,提出了针对无人直升机超低空电力线巡线的自动航迹布设及优化方案,并系统阐述了航迹分段布设、航迹平滑、航迹异常检测和优化等关键技术算法。实验结果表明,该方案可以为无人直升机进行超低空的电力线巡线设计出安全、可靠的航迹。     

考虑地球扁率的RNAV航路规划

考虑地球扁率的影响,在地理坐标系下推算区域导航(RNAV)航路点的经纬度坐标以及各航段的初始真航线角(TC)与航线距离,为机载区域导航设备提供更为精确的航迹指引和更为快捷的直飞航线。以IAG-75椭球参数为计算依据,根据空间向量分析,导出了RNAV大椭圆圈航线的初始TC、航线距离以及基于中间插值的航路点纬度计算方法。经计算,从B215航路的阜康至大王庄,现行等角航线距离为2642km,简化大圆航线模型的航线距离为2423.8km,而考虑地球扁率影响的大椭圆航线模型的航线距离为2435.3km。     

出行认知约束下的最优路径规划方法

基于城市交通与城市形态结构的密切关系,本文探讨了环形城市形态下的城市交通网模型,并提出了结合大众出行认知特征的城市交通最优路径规划方法。为检验本文方法的有效性,利用成都市路网数据对本方法与传统路径规划方法进行了对比实验,结果表明本文方法所规划路径更适应实际状况,可有效地降低时间消耗、较好地符合层次空间推理机制。     

面向东川复杂山地滑坡体无人机立面航线规划及建模分析

以单镜头四旋翼小型无人机为试验设备,针对复杂山地地区单一、高落差滑坡体,本文提出采用面向滑坡体立面航线规划,结合传统单水平航线、井字形交叉航线规划,构建不同航线下的三维模型.通过重叠度、三维模型完整性、布设地面标靶分析三维模型精度3个方面,对不同航线下构建三维模型的方法进行评价分析.试验结果表明,采用立面航线能达到98...     

一种基于遗传算法的多模式多标准路径规划方法

单一路径评价标准难以满足日益多样化的出行路径规划需求。多标准路径规划成为公众出行服务的研究热点。然而,多标准路径规划本质上是具有NP特性的多标准决策问题,且涉及多种交通出行模式。多个不同标准的权重设置将直接影响路径规划结果。因此,如何科学合理地设置不同标准的权重成为多标准路径规划中的技术瓶颈。本文提出了一种适应多模式交通网络环境的多标准路径规划方法,借鉴遗传算法在求解多标准优化问题中的优势,将其扩展到多模式多标准路径规划中。该方法避免了不同出行标准权重设置中的主观性和不确定性,能够实现更为灵活的交通出行模式自动化组合,为出行者提供满足个性化需求的、多标准的出行路径规划服务。     

多旋翼单镜头无人机不同航线规划的三维建模方法评述

选用多旋翼单镜头无人机作为航摄设备,对同一建筑物规划交叉航线、全航线及5架次模拟航线,构建该建筑物的实景三维模型,并从模型完整性和地面控制点点位精度两个方面对3种不同航线三维建模方法进行评述。结果表明:①交叉航线建模方法控制点点位精度高,但模型完整性差;②全航线建模方法控制点点位精度高,模型完整性较高;③5架次模拟航线建模方法控制点点位精度略低,模型完整性最好。     

大型网络中容量受限的疏散路径规划方法

针对启发式算法利用Dijkstra算法求解大型动态网络中疏散路径规划问题时,存在疏散时间长、稳定性差等不足,该文提出了一种改进CCRP的方法,即用蚁群算法替代Dijkstra算法求解最优路径,进而减少疏散时间,增加估算疏散时间的精确性。实验表明,该方法能够在大型动态网络下实现路网容量受限的疏散路径规划有效求解,具有疏散时间短、疏散路径少、线性关系强等特点,相比原有CCRP算法更能满足实际疏散的需要。在寻找最优路径上采用蚁群算法求解,相比贪心算法更能支持全局最优、并行计算、疏散效率更高,在支持路况信息实时更新、大规模人群快速疏散、及时调整疏散路线等方面更具优势。     

不同地形环境下无人机航线规划及三维建模分析

针对不同地形环境下存在的飞行安全性低、数据冗余、构建三维模型质量和精度差等问题,本文以单镜头四旋翼小型无人机为试验设备,对平坦地形环境下的复杂单体建筑使用井字形交叉航线和环视航线;对复杂山地地形环境下的泥石流沟谷使用水平航线、井字形交叉航线及视频航线构建三维模型,并结合航线参数、三维模型质量和精度,探讨了不同地形环境下无人机航线规划方案对三维模型构建的影响。经评价分析可知:①使用环视航线能安全、快速地获取平坦地形下的复杂单体建筑影像,构建完整、质量好、精度高的三维模型;②使用井字形交叉航线能构建山地地形下泥石流沟谷的完整、质量好、精度高的三维模型,但飞行安全性、时效性较低;③使用视频航线,影像重叠度高,能构建完整、质量好的三维模型,模型精度并无明显差异。     

嵌入式GIS中最优路径规划算法研究与实现

针对现有大区域范围路径规划算法存在的一些问题,提出一种多比例尺最优路径规划算法。该算法在进行路径规划时,在小区域范围内根据道路的属性信息对路网进行分层,在大区域范围内根据多比例尺信息对路网进行分级,在每级或每层内采用基于弧段的改进型A*算法。从实例分析可以看出,该算法能较好满足车载导航系统的需求。     

一种林业有害生物外业调查路线的规划方法

针对青岛市利用遥感技术辅助指导枯死松木地面调查的新模式,旨在解决外业调查区划和多点路线选择问题。基于DEM数据设计和实现了复杂地形下两调查点之间互相抵达的路径成本算法,在计算中考虑了地形因素的影响。将调查区域内调查点两两之间的路径成本构造成矩阵,并采用蚁群算法求解出一条总成本较小的路径。经实验与实地验证,所提方法能够合理规划出调查线路,有效避开河流、陡坡等自然屏障,科学指导和监督地面调查工作。     

Strategies for Watershed Management planning using remote sensing technique

‘Watershed Management’ has assumed urgency for planned development of land and water resources and to arrest land degradation process to preserve environment and ecological balance. Decision support to such management planning requires scientific knowledge of resources information, expected runoff and sediment yield, priority classification of watersheds for conservation planning, monitoring of watershed for environmental impact assessment and technologies of GIS for data base creation, scenario development and appropriate decision making. Remote sensing technique is ideally suited to evolve such a management strategy. Scientific basis of this approach is explained.     

多尺度边缘动态规划立体匹配算法

目前大多数立体匹配方法都是基于像素处理,而以面向对象的方式进行立体匹配则更加符合人类视觉习惯。该文提出一种面向对象的多尺度递进的立体匹配算法,实现由粗到细的快速立体匹配。首先对参考图进行粗分割获取目标对象,然后针对目标区域采用边缘线动态规划的方法获取视差,再根据精度需求进一步判断该目标是否需要细分以获取更加精细的视差,最后得到有效的视差图。实验证明,这种方法以目标区域为对象避免了从像素级逐一运算,不仅使处理速度加快,而且还能保持有效精度。     

Design of survey systems using nonlinear programming methods

This paper discusses theory and results of an attempt to use non-linear programming methods to arrive at an optimal, in the sense of least cost, solution to the design of a survey system to meet specified accuracy. In other words, the method determines the combination of various types of observations which will yield the required accuracy of control points for a minimum cost. The theoretical background of the procedure is discussed, and methods of extension to photo-grammetry and other sciences are presented. Much of the paper is concerned with discussing results of numerical solutions for the optimal design of several small, but typical, mapping problems. It is believed that this research is original with the author, as extensive literature searches and correspondence has produced no knowledge of prior research into this application of nonlinear programming. The method at its current state of development appears to be capable of yielding significant improvements to the present concepts of survey network design.     

Optimizing GPS-guidance transit route for cable crane collision avoidance using artificial immune algorithm

GPS Solutions - A cable crane collision accident usually causes serious damage to workers, equipment and materials. Owing to the emergence of global position system (GPS), some new collision...     

面向直升机低空突防的三维航线规划算法研究

直升机低空突防航线规划对保障直升机安全飞行,顺利完成任务至关重要。综合考虑地形、雷达探测、火力威胁的影响,将规划空间栅格化剖分,设计直升机低空突防航线;根据障碍物分布以及直升机自身性能的限制,对突防航线进行优化得到最佳突防航线。仿真实验验证了算法的有效性。     

Fitting boxes to Manhattan scenes using linear integer programming

We propose an approach for automatic generation of building models by assembling a set of boxes using a Manhattan-world assumption. The method first aligns the point cloud with a per-building local coordinate system, and then fits axis-aligned planes to the point cloud through an iterative regularization process. The refined planes partition the space of the data into a series of compact cubic cells (candidate boxes) spanning the entire 3D space of the input data. We then choose to approximate the target building by the assembly of a subset of these candidate boxes using a binary linear programming formulation. The objective function is designed to maximize the point cloud coverage and the compactness of the final model. Finally, all selected boxes are merged into a lightweight polygonal mesh model, which is suitable for interactive visualization of large scale urban scenes. Experimental results and a comparison with state-of-the-art methods demonstrate the effectiveness of the proposed framework.     

Evolutionary Multi-objective Optimization for landscape system design

Increasing recognition of the extent and speed of habitat fragmentation and loss, particularly in the urban fringe, is driving the need to analyze qualitatively and quantitatively regional landscape structures in land-use planning and environmental policy implementation. This paper introduces an Evolutionary Multi-objective Optimization (EMO) methodology to estimate the Pareto optimal set of landscape designs generated from a series of underlying ecological principles. The results of applying these principles via EMO to a study site are presented and a hierarchical clustering methodology is introduced to assist in evaluating the population of solutions generated.     

实景三维在输变电工程选线规划中的应用

输变电工程选线制约因素较多,受环境影响十分明显,传统二维图选结合现场勘察的工作方式,不仅费时费力,而且无法全面掌握线路上的自然条件,导致选线效果难以保证。本文利用实景三维对输变电工程的选线规划进行了研究;在真实地理场景中进行选线范围约束、线路标绘及实景模拟,并结合空间分析技术辅助方案比选,为科学合理选线提供了一种新的思路。实践证明,在黄埠岭500 kV输变电工程建设项目中,实景三维以其真实、立体、直观的表达优势,不仅可以提高选线效率和质量,还可以在穿越风景区等特殊线路段上开展景观视觉影响分析,为方案比选与论证提供科学客观的决策参考,是对输电线路数字化选线的一次深度赋能。