国企客运车辆公车公营模式分析

本文通过对国企客运车辆的现状分析,提出从挂靠转变为"公车公营"的车辆经营模式,并给出相应措施,对国有客运企业整体发展意义重大。     

一种盘旋算法在无人机搜索任务中的应用研究

针对无人机应急搜索中地面目标定位问题,提出一种基于"∞"型盘旋动作的航路规划方法。文章分别对圆、椭圆、"∞"型盘旋算法在应用环境、定位精度及定位盘旋圈数等方面进行了对比分析,并基于VC6.0开发了定位盘旋控制软件。经飞行测试表明,该算法能有效缩短定位时间和空中盘旋圈数,定位速率更高、适应能力更强。从而实现无人机搜救系统的高效搜索。     

政府补助方式对新能源汽车企业绩效影响研究

以2010－2015年新能源汽车行业上市公司面板数据为样本,区分政府补助方式,实证分析政府研发补助和非研发补助对企业绩效的影响。研究表明：政府研发补助对企业创新绩效有显著正向影响;政府非研发补助对企业经营绩效有显著正相关作用,且随着企业经营绩效提升,政府非研发补助对企业研发投入起到间接正向作用;企业研发投入在政府补助与企业创新绩效中存在部分中介效应。根据企业成长性对样本进行分组,进一步发现政府研发补助对高成长性企业创新绩效具有显著促进作用,而对低成长性企业无显著影响;政府非研发补助对企业经营绩效均有显著正向影响,对高成长性企业的影响更突出。     

专利信息视域下纯电动汽车技术研发竞争态势研究

纯电动汽车是完全由可充电电池提供动力源的汽车,其具有无污染、噪声小等优点,是世界主要汽车国家争相研发的技术。从专利数据出发,基于年度分布、专利技术生命周期、优先权专利地区分布、主要国家专利布局、主要竞争对手研发力量与研发效率以及主要企业技术专利布局视角,结合发展现状,系统分析了国际纯电动汽车的发展态势以及我国在该领域的竞争地位,可为我国产业战略布局和技术研发提供借鉴。     

网络视角下战略性新兴产业技术创新小生境演化研究

运用生态学小生境理论分析新兴技术演化和产业技术创新问题是当前的研究焦点。基于网络视角,通过引入期望机制、力量机制和知识机制3个指标维度,将技术创新小生境划分为缺失期、萌发期、胚胎期、原型期、成长期和成熟期6个演化阶段。选取我国内地27个省市自治区新能源汽车产业相关数据,采用社会网络分析法进行实证分析。在确定各地区技术创新小生境演化阶段的同时,归纳出3种技术创新小生境模式,分别为关键技术主导型、科技孵化支撑型和集成创新驱动型。通过进一步对核心技术演化过程进行分析,发现主导、竞争、共生构成了核心技术演化态势。最后,提出了完善自我保护机制、构建协同共生模式和优化创新生存因子的相关政策与建议。     

The Self-Learning Particle Swarm Optimization approach for routing pickup and delivery of multiple products with material handling in multiple cross-docks

Vehicle Routing Problems (VRPs) in distribution centers with cross-docking operations are more complex than the traditional ones. This paper attempts to address the VRP of distribution centers with multiple cross-docks for processing multiple products. In this paper, the mathematical model intends to minimize the total cost of operations subjected to a set of constraints. Due to high complexity of model, it is solved by using a variant of Particle Swarm Optimization (PSO) with a Self-Learning strategy, namely SLPSO. To validate the effectiveness of SLPSO approach, benchmark problems in the literature and test problems are solved by SLPSO.     

Three effective metaheuristics to solve the multi-depot multi-trip heterogeneous dial-a-ride problem

The Heterogeneous Dial-a-Ride Problem (HDARP) is an important problem in reduced mobility transportation. Recently, several extensions have been proposed towards more realistic applications of the problem. In this paper, a new variant called the Multi-Depot Multi-Trip Heterogeneous Dial-a-Ride Problem (MD-MT-HDARP) is considered. A mathematical programming formulation and three metaheuristics are proposed: an improved Adaptive Large Neighborhood Search (ALNS), Hybrid Bees Algorithm with Simulated Annealing (BA-SA), and Hybrid Bees Algorithm with Deterministic Annealing (BA-DA). Extensive experiments show the effectiveness of the proposed algorithms for solving the underlying problem. In addition, they are competitive to the current state-of-the-art algorithm on the MD-HDARP.     

The heterogeneous green vehicle routing and scheduling problem with time-varying traffic congestion

The green vehicle routing and scheduling problem (GVRSP) aims to minimize green-house gas emissions in logistics systems through better planning of deliveries/pickups made by a fleet of vehicles. We define a new mixed integer liner programming (MIP) model which considers heterogeneous vehicles, time-varying traffic congestion, customer/vehicle time window constraints, the impact of vehicle loads on emissions, and vehicle capacity/range constraints in the GVRSP. The proposed model allows vehicles to stop on arcs, which is shown to reduce emissions up to additional 8% on simulated data. A hybrid algorithm of MIP and iterated neighborhood search is proposed to solve the problem.     

A tabu search heuristic for the heterogeneous vehicle routing problem on a multigraph

We study a time-constrained heterogeneous vehicle routing problem on a multigraph where parallel arcs between pairs of vertices represent different travel options based on criteria such as time, cost, and distance. We formulate the problem as a mixed-integer linear programming model and develop a tabu search heuristic that efficiently addresses computational challenges due to parallel arcs. Numerical experiments show that the heuristic is highly effective and that freight operators can achieve advantages in cost and customer service by considering alternative paths, especially when route duration limits are restrictive and/or when vehicles of smaller capacity are dispatched to serve remote customers.     

Planning towing processes at airports more efficiently

This paper addresses the towing process of airplanes as part of the turnaround process. We introduce a VRP based MIP model which assigns different types of towing tractors to jobs with specified service time windows. The objective function minimizes operating costs subject to operational restrictions such as technical compatibility of tractor types with plane types. Our modeling approach allows for multiple depots as well as multiple trips. To solve the model we develop a column generation heuristic. Computational results show the superior behavior of the proposed heuristic compared to the original MIP formulation solved with CPLEX. In a case study we derive insights which support schedulers in their daily work. For this, we identify cost drivers and evaluate the efficiency of manual schedules in retrospect.