HEC Montréal

About: HEC Montréal is a education organization based out in Montreal, Quebec, Canada. It is known for research contribution in the topics: Context (language use) & Vehicle routing problem. The organization has 1221 authors who have published 5708 publications receiving 196862 citations. The organization is also known as: Ecole des Hautes Etudes Commerciales de Montreal & HEC Montreal.

Solving the Capacitated Location-Routing Problem by a Cooperative Lagrangean Relaxation-Granular Tabu Search Heuristic

Abstract: Most of the time in a distribution system, depot location and vehicle routing are interdependent, and recent studies have shown that the overall system cost may be excessive if routing decisions are ignored when locating depots. The location-routing problem (LRP) overcomes this drawback by simultaneously tackling location and routing decisions. This paper presents a cooperative metaheuristic to solve the LRP with capacitated routes and depots. The principle is to alternate between a depot location phase and a routing phase, exchanging information on the most promising edges. In the first phase, the routes and their customers are aggregated into supercustomers, leading to a facility-location problem, which is then solved by a Lagrangean relaxation of the assignment constraints. In the second phase, the routes from the resulting multidepot vehicle-routing problem (VRP) are improved using a granular tabu search (GTS) heuristic. At the end of each global iteration, information about the edges most often used is recorded to be used in the following phases. The method is evaluated on three sets of randomly generated instances and compared with other heuristics and a lower bound. Solutions are obtained in a reasonable amount of time for such a strategic problem and show that this metaheuristic outperforms other methods on various kinds of instances.

The impact of structuring characteristics on the launching of virtual communities of practice

Abstract: Purpose – Despite the increasing popularity of virtual communities of practice (VCoPs), our understanding of how to intentionally form, develop and sustain them is still at an embryonic stage. Aims to go some way to remedying this.Design/methodology/approach – Investigates the attempt by 14 organizations to implement 18 VCoPs. Using existing documents, detailed logs, and focus groups, a large quantity of qualitative data was gathered, coded, and analyzed.Findings – The study shows that the environment, the relevance of the VCoP's objectives to its members' daily work, and the degree to which the VCoP is embedded in the organizational structure of an organization are the three structuring characteristics most likely to explain the success or failure of a VCoP at the launching stage.Research limitations/implications – The focus is limited to the launching phase; further research should investigate different stages of development.Practical implications – The results may offer an indication as to the most imp...

Understanding union power: resources and capabilities for renewing union capacity

Abstract: Power is at the core of current debates over the future of trade unionism. This article provides a framework to assess the power resources and strategic capabilities central to union capacity building. We identify four key power resources: internal solidarity; network embeddedness; narrative resources that frame understandings and union actions; and infrastructural resources (material, human, processes, policies and programmes). Resources alone are not enough; unions must also be capable of using them. We identify four strategic capabilities: intermediating between contending interests to foster collaborative action and to activate networks; framing; articulating actions over time and space; and learning. Much experimentation and research on the interactions between these resources and capabilities in particular contexts is required to advance our understanding of the renewal of union power.

Parallel Tabu search heuristics for the dynamic multi-vehicle dial-a-ride problem

Abstract: In the Dial-a-Ride problem (DARP) users specify transportation requests between origins and destinations to be served by vehicles. In the dynamic DARP, requests are received throughout the day and the primary objective is to accept as many requests as possible while satisfying operational constraints. This article describes and compares a number of parallel implementations of a Tabu search heuristic previously developed for the static DARP, i.e., the variant of the problem where all requests are known in advance. Computational results show that the proposed algorithms are able to satisfy a high percentage of user requests.