Frictional Behavior and Surface Failure of Acrylic Denture Teeth

The wear characteristics of acrylic denture teeth were investigated under single- and double-pass sliding. The response of acrylic teeth to sliding was that of a relatively ductile material. The wear characteristics were affected similarly by environments of water and saliva. The "enamel" surfaces showed more resistance to penetration and were less susceptible to surface damage than the "dentin" surfaces. The effect of the second pass was to increase track width and cause a more severe mode of surface failure.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67388/2/10.1177_00220345810600051001.pd

Sintered Hydroxyapatite Ceramic for Wear Studies

A sintered hydroxyapatite (HAP) ceramic for use in wear studies was prepared from a commerical tricalcium phosphate. The sintered HAP had physical properties close to those of human enamel. The coefficient of friction and wear of the sintered HAP ceramic as characterized by tangential force, track width, and surface failure data, approximated those of human enamel.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67948/2/10.1177_00220345780570070401.pd

Intensification/Diversification-Driven ILS for a Graph Coloring Problem

International audienceThis paper presents an extension of the ILS algorithm, called ID-ILS, by introducing new local search devices that enforce an efficient tradeoff of intensification and diversification. Experiments performed on the DIMACS benchmarks show that our method is competitive with the best coloring algorithms

A Critical Element-Guided Perturbation Strategy for Iterated Local Search

Abstract. In this paper, we study the perturbation operator of Iterated Local Search. To guide more efficiently the search to move towards new promising regions of the search space, we introduce a Critical Element-Guided Perturbation strategy (CEGP). This perturbation approach consists of the identification of critical elements and then focusing on these critical elements within the perturbation operator. Computational experiments on two case studies—graph coloring and course timetabling—give evidence that this critical element-guided perturbation strategy helps reinforce the performance of Iterated Local Search