Materialization and hierarchical routing algorithms are becoming important tools in querying databases for the shortest paths in time-critical applications like Intelligent Transportation Systems (ITS), due to the growing size of their spatial graph databases 16]. A hierarchical routing algorithm decomposes the original graph into a set of fragment graphs and a boundary graph which summarizes t...

Demands on networking infrastructure are growing exponentially due to bandwidth-hungry applications such as rich media applications and inter-data-center communications. In this context, it is important to optimally use the bandwidth in wired networks that extensively use link aggregation groups and equal-cost multipaths as techniques for bandwidth scaling. This document explores some of the me...

Ravindra K. Ahuja and Dorit S. Hochbaum Abstract In this paper, we study capacitated dynamic lot sizing problems with or without backorders, under the assumption that production costs are linear, that is, there are no set up costs. These two dynamic lot sizing problems (with or without backorders) are minimum cost flow problems on an underlying network that possess a special structure. We show ...

Taxonomies of concepts are important across many application domains, for instance online shopping portals use catalogs to help users navigate and search for products. Task-dependent taxonomies, e.g., adapting the taxonomy to a specific cohort of users, can greatly improve the effectiveness of navigation and search. However, taxonomies are usually created by domain experts and hence designing t...

The advancement of mobile technologies and the proliferation of map-based applications have enabled a user to access a wide variety of services that range from information queries to navigation systems. Due to the popularity of map-based applications among the users, the service provider often requires to answer a large number of simultaneous queries. Thus, processing queries efficiently on spa...

A common method of recovering a delayed construction programme is by schedule compression through activity crashing. To be of practical benefit, however, the cost-effectiveness of crashing any of the remaining construction activities needs be examined before a decision is reached. Although the likely cost and productivity effects of crashing can be calculated using standard estimating technique...

Shortest path query is an important problem and has been well studied in static graphs. However, in practice, the costs of edges in graphs always change over time. We call such graphs as timedependent graphs. In this paper, we study how to find a costoptimal path with time constraint in time-dependent graphs. Most existing works regarding the Time-Dependent Shortest Path (TDSP) problem focus on...

The overall aim of this study is to empirically investigate the cost structure of a management agreement type agri-environmental instrument and to identify factors for cost variation over space and time. We control for the actual level of compliance by using compliance weighted average scheme cost ratios. Beside technological and economic performance measures, we also incorporate risk proxies. ...

As the migration of wireless communication network from one generation to another continue, radio wave propagation model or path loss model plays a very significant role in achieving an optimum performance as well as suitability over different locations of interest. In this research, investigation of radio communication channel behavior based on practical measurement in the L-band frequency in ...

This paper considers minimax regret 1-sink location problems in dynamic path networks. A dynamic path network consists of an undirected path with positive edge lengths and constant edge capacity and the vertex supply which is nonnegative value, called weight, is unknown but only the interval of weight is known. A particular assignment of weight to each vertex is called a scenario. Under any sce...