Received December 24, 2010 Revised May 26, 2011 Web directories allow Web users to browse a hierarchy of categories, under which different types of resources are classified. We study the problem of maintaining a Web directory, that is, the problem of continually discovering and ranking resources that are relevant to the categories of the directory. We propose an unsupervised computational metho...

UniChem is a freely available compound identifier mapping service on the internet, designed to optimize the efficiency with which structure-based hyperlinks may be built and maintained between chemistry-based resources. In the past, the creation and maintenance of such links at EMBL-EBI, where several chemistry-based resources exist, has required independent efforts by each of the separate team...

Within the Department of Defense (DoD), mission-critical software maintenance has been reported to cost between $700 million and $20 billion annually. The wide range of estimates results from uncertainty over the definitions of “mission-critical” and “software maintenance” as well as the lack of any catalog of performing activities. The problem is deeper than definitions and level of investment...

We propose in this study a hierarchical method for the problem of scheduling N jobs on M parallel machines where each machine should be maintained once during the planning horizon. The maintenance tasks should be continuously executed because the maintenance resources are not sufficient. Our objective is to find a schedule composed of the jobs and the maintenance tasks in which the total sum of...

While the extraordinary life span of queens and division of labor in eusocial societies have been well studied, it is less clear which selective forces act on the short life span of workers. The disparity of life span between the queen and the workers is linked to a basic issue in sociobiology: How are the resources in a colony allocated between colony maintenance and reproduction? Resources fo...

In general the objective of E-Maintenance is to organize, structure and link the Information and Communication Technologies (ICT) to develop a maintenance support system that is effective and efficient during the whole life cycle of the product. Among the many challenges of E-Maintenance, human centered solutions that can better assist technicians and engineers are emerging, using ICT resources...

Optimised maintenance can reduce operating costs by demanding less resources and avoiding equipment breakdown, hence ensuring that daily manufacturing and production will not be interrupted. Web-based maintenance is one of the most efficient methods for optimising maintenance. The Web-based maintenance system that we have developed uses virtual instruments, to provide remote sensing, monitoring...

The optimal use of legume genetic resources represents a key prerequisite for coping with current agriculture-related societal challenges, including conservation agrobiodiversity, agricultural sustainability, food security, and human health. Among legumes, the common bean (Phaseolus vulgaris) is most economically important consumption, its evolutionary trajectories as species have been crucial ...

the conventional method towards deriving schedule for a fleet of ships to minimize cost alone has the short-coming of not addressing the problem of operation revenue losses associated with delays during maintenance at ships dockyards. in this paper, a preventive maintenance schedule for a fleet of ships that incorporates op-portunity cost is presented. the idea is to assign a penalty cost to al...