多任务调度实现四足机器人运动控制

基于μC/OS-Ⅱ实时操作系统的多任务调度原理,对四足机器人规划层的任务进行了划分及详细阐述,并进行了优先级的设计,最终实现了四足机器人的运动控制。     

基于优先权的多应急点资源调度模型研究

大型突发事件由于影响规模广、破坏程度大,需要多个资源供应点向多个灾害点调度各类急需资源,研究多灾害点的情况具有很强的现实意义,研究主要解决多应急点资源调度问题。通过确定各个应急点的优先权建立多应急点资源调度模型,并用算例进行了分析。     

Knowledge acquisition using psychotherapy technique for critical factors influencing construction project layout planning

The positioning of equipment on a construction site may change in different construction phases, different environments, and different types of end products, which greatly influence the decision of the site planning engineer who seeks to maximize the construction efficiency by minimizing the friction from the site layout. This study aims to acquire and analyze site planning experts' knowledge on critical factors influencing the construction layout planning using a psychotherapy technique. Through an open‐structured interview survey and cluster analysis, 125 core factors influencing the site layout plan were analyzed and categorized into a database.     

Scheduling-capable autonomic manager for policy-based IT change management system

Managing large IT environments is expensive and labour intensive. Maintaining and upgrading with minimal disruption and administrative support has always been a challenging task for system administrators. One challenge faced by IT administrators is arriving at schedules for applying one or more change requests to one of the system components. Most of the time, the impact analysis of the proposed changes is done by humans and is often laborious and error-prone. Although this methodology might be suitable to handle changes that are planned way ahead in time, it is completely inappropriate for changes that need to be done sooner. In addition, such manual handling does not scale well with the size of the IT infrastructure. In this article, the focus is on the problem of scheduling change requests in the presence of organisational policies governing the use of its resources. The authors propose two approaches for change management scheduling and present the implementation details of two prototypes that prove the feasibility of the proposed approaches. Their implementation is integrated with an autonomic manager which they had described in their earlier work.     

突发事件下应急物资调度评价体系研究

结合突发事件下应急物资调度的现状,提出了影响应急物资调度的4个因素:时间、成本、受灾点的满意度和敏捷性,最后运用层次分析法确定各指标的权重,经计算分析可知应急响应时间是否最短、调度方案是否体现出系统协调性及应急物资调度成本是否最小这3项指标对应急物资调度的影响程度最大。     

A Western Australian Test of Invariant Factorial Structure in the Work Autonomy Scale Between Managerial and Non-Managerial Employee Classifications

ABSTRACT

This paper explores the conceptualisation of work autonomy through an investigation of the factorial structure stability of the Global Work Autonomy Scale at different employee levels. After administering the Global Work Autonomy Scale (Breaugh, 1985) to employees in a public sector organisation, analysis of responses confirmed an a priori three-factor model of work autonomy (method autonomy, scheduling autonomy and criteria autonomy) in a group of non-managerial employees (n = 193). A subsequent multi-sample analysis was conducted to test the invariance of the three-factor model for a group of managerial employees (n = 205). After constraining factor loadings and factor covariances, the hypothesised model continued to provide a reasonable fit to the data, confirming the generalisability of the three-factor model to both employee classifications. The methodological and theoretical implications for research into work autonomy are discussed.     

An exact algorithm for the multi-trip vehicle routing and scheduling problem of pickup and delivery of customers to the airport

Door-to-Door service of Pickup and Delivery of Customers to the Airport (D2PDCA) is a new service provided by certain Airline Ticket Sales Agencies (ATSAs) in China. This new service provides an attractive alternative way by picking up customer at this/her specified position and at any time he/she preferred and delivering to the airport more conveniently than airport shuttle and thus earn high customer service quality. Compared with the single-trip mode, the multi-trip mode of D2PDCA (MTM-D2PDCA) service can reduce travel distances, the number of vehicles required and the operating cost. To obtain the exact solution of the MTM-D2PDCA problem, we propose a novel, exact algorithm based on the trip-chain-oriented set-partitioning (TCO-SP) model, where a trip-chain represents multiple trips made by a specific vehicle. In the exact algorithm, we propose an improved label-correcting method to remove infeasible trip-chains quickly and thus speed the search process. Based on the feasible trip-chains, the MTM-D2PDCA problem is formulated as the novel TCO-SP model, which can be solved exactly by the optimization software CPLEX. In addition, we present several mathematical insights into the relationship between the number of trip-chains and the number of local optimal trips that are applicable in both theory and practice. Extensive experiments are conducted to illustrate the application of the model and demonstrate the cost savings of the MTM-D2PDCA mode over the single-trip mode and provide managerial insights into successfully operating a MTM-D2PDCA service.     

Control-based optimization approach for aircraft scheduling in a terminal area with alternative arrival routes

This paper presents an optimization approach for dynamically scheduling aircraft operations and supporting air traffic controllers in both determining and implementing operationally feasible landing and departure times at an airport. The mixed integer linear programming model proposed incorporates air traffic control infrastructure in terms of route network, introduces the concept of alternative approach routes and is designed to generate an output that can be converted into effective advisories for executable flight commands. It shows reasonable computational times for obtaining the optimal solution and delay reductions of up to 35% with practical size instances from Sao Paulo/Guarulhos International Airport.     

A heuristic approach for solving an integrated gate reassignment and taxi scheduling problem

Capacity limitation of airport ground operation is one of the major limiting factors in air traffic operation. The congestion on the gate and taxiway causes severe delay and propagate effect on the flight schedule. This paper considers the problem of integrated gate reassignment and taxiway scheduling, in which complex constraints related to runway restriction, gate allocation and taxiway conflict are all incorporated when determining the schedule. To solve this problem, we propose a novel heuristic approach. First, all possible aircraft schedules are enumerated by disretizing the waiting time along the path. Then, the cost is evaluated for each schedule and the conflict detection is conducted to generate constraint sets. Finally, we propose a set partition model, in which each decision variable denotes a candidate schedule that takes into account the possible constraints when generated. This method is compared with a sequential method that solves gate reassignment and taxiway scheduling problem separately. Computational results highlight the strength of our method.     

遗传算法在拖轮调度中的应用

根据某港口的实际情况,分析拖轮工作的工作过程和特点,以拖轮编号作为编码形式,将遗传算法应用到拖轮调度系统中,实现优化调度,提高拖轮作业的效率。