Exact and Efficient Heuristic Deployment in WSN under Coverage, Connectivity, and Lifetime Constraints

Wireless sensor networks lay down many challenging optimization problems, such as coverage, node deployment, tracking or energy conservation. In this paper, we are interested in deployment strategies that result in a minimum of sensors network while ensuring target coverage connectivity between the sensors and sink. To this end, we propose two alternative deployment approaches based on integer linear programming and we exploit the linear-programming sequential fixing technique to design three polynomial-time heuristic procedures. The performance and effectiveness of these approaches in terms of network cost and computational requirements are highlighted through several experiments. Furthermore, we investigate the network lifetime problem where a given operational duration must be reached.

Methods of the automated aircraft configuration

Aircraft are great and comprehensive technical systems, which are characterised by the great configuration density. This article presents formation of the geometrical conceptual design of the aircraft on the basis of the formal heuristic procedures within the framework of the infrastructural constraints. In addition, this article includes description of influence of the aerodynamic configuration and the volume-weight configuration upon formation of the geometrical conceptual design of the aircraft, as well as description of other mass/inertia characteristics of the aggregates, which are to be installed within the specific aircraft. This article also states that in the case of the "very strict" infrastructural constraints, it is necessary to solve "the inverse" problem of configuration, that is the problem, where initial data for formation of the geometrical conceptual design of the aircraft are determined by the necessary configuration space, which is determined by the infrastructural constraints. The article presents the project problem (in aggregate) of finding rational values for parameters of the geometrical conceptual design of the aircraft as the problem of the multiple criteria discrete optimisation. This article states that it is possible to formulate this problem as the search of the vector of structural parameters (that is, search of the multitude of the admissible alternatives of the drawing and designing solutions).

Algorithms with greedy heuristic procedures for mixture probability distribution separation

For clustering problems based on the model of mixture probability distribution separation, we propose new Variable Neighbourhood Search algorithms (VNS) and evolutionary genetic algorithms (GA) with greedy agglomerative heuristic procedures and compare them with known algorithms. New genetic algorithms implement a global search strategy with the use of a special crossover operator based on greedy agglomerative heuristic procedures in combination with the EM algorithm (Expectation Maximization). In our new VNS algorithms, this combination is used for forming randomized neighbourhoods to search for better solutions. The results of computational experiments made on classical data sets and the testings of production batches of semiconductor devices shipped for the space industry demonstrate that new algorithms allow us to obtain better results, higher values of the log likelihood objective function, in comparison with the EM algorithm and its modifications.

Jaya Algorithm-Assisted Evaluation of Tooth Elements Using Digital Bitewing Radiography Images

A considerable number of heuristic procedures are widely implemented to evaluate biomedical images. This chapter proposes an evaluation procedure for digital bitewing radiography (DBR) images using the Jaya algorithm. The proposed procedure implements an image processing technique by integrating of the multi-thresholding and segmentation procedure to extract the essential tooth elements recorded with DBR. In this paper, 80 dental x-ray images are considered for the evaluation. The performance of the proposed procedure is confirmed using a relative assessment between the extracted section and its corresponding ground-truth. The results of this study confirm that, for most of the DBR cases, the proposed approach offers better values of picture likeliness measures. Hence, this technique can be considered for the automated detection of tooth elements from the DBR obtained from clinics.

Discretization Based Heuristics for the Capacitated Multi-facility Weber Problem with Convex Polyhedral Barriers

The Capacitated Multi-facility Weber Problem addresses optimally locating I capacitated facilities in the plane and satisfying demand of J customers so as to minimize the total transportation cost. It assumes that facilities can be located anywhere on the plane and customers are directly connected to them. This study considers the case where there exist convex polyhedral barriers blocking passage and locating facilities inside. Then, the distances between facilities and customers have to be measured by taking into account the polyhedral barriers. The resulting problem is non-convex and difficult to solve. We propose several discretization based heuristic procedures which are especially designed for the problem. The performance of the suggested methods are tested on an extensive set of randomly generated test instances which are derived from standard test instances. Our results imply that the suggested heuristics yield very accurate and efficient solutions for this problem.

Exact and Efficient Heuristic Deployment in WSN under Coverage, Connectivity, and Lifetime Constraints

Wireless sensor networks lay down many challenging optimization problems, such as coverage, node deployment, tracking or energy conservation. In this paper, we are interested in deployment strategies that result in a minimum of sensors network while ensuring target coverage connectivity between the sensors and sink. To this end, we propose two alternative deployment approaches based on integer linear programming and we exploit the linear-programming sequential fixing technique to design three polynomial-time heuristic procedures. The performance and effectiveness of these approaches in terms of network cost and computational requirements are highlighted through several experiments. Furthermore, we investigate the network lifetime problem where a given operational duration must be reached.