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Water conveyance systems (WCSs) are costly infrastructures in terms of materials, construction, maintenance and energy requirements. Much attention has been given to the application of optimization methods to minimize the costs associated with such infrastructures. Historically, traditional optimization techniques have been used, such as linear and non-linear programming. In this paper, application of ant colony optimization (ACO) algorithm in the design of a water supply pipeline system is presented. Ant colony optimization algorithms, which are based on foraging behavior of ants, is successfully applied to optimize this problem. A computer model is developed that can receive pumping stations at any possible or predefined locations and optimize their specifications. As any direct search method, the mothel is highly sensitive to setup parameters, hence fine tuning of the parameters is recommended.

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An important factor in the design and implementation of structural control strategies is the number and placement of actuators. By employing optimally-located actuators, the effectiveness of control system increases, while with an optimal number of actuators, an acceptable level of performance can be achieved with fewer actuators. The method proposed in this paper, simultaneously determines the number and location of actuators, installed in a building, in an optimal sense. In particular, a genetic algorithm which minimizes a suitably defined structural damage index is introduced and applied to a well-known nonlinear model of a 20-story benchmark building. It is shown in the paper that an equal damage protection, compared to the work of other researchers, can be achieved with fewer numbers of optimally placed actuators. This result can be important from economic point of view. However, the attempt to minimize one performance index has negative effect on the others. To cope with this problem to some extent, the proposed genetic methodology has been modified to be applied in a multi-objective optimization problem.

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Employer Organizations have increasingly interested in outsourcing their projects in the form of public-private partnership (PPP) due to various reasons such as compromising the resource limitations, entering new technologies to the organization and reducing risk. Choosing the private sector as one of the most basic steps in the formation of PPP is of great importance. The present study aims to introduce a hybrid model to evaluate and choose the private sector as one of the parties in PPP using a combination of SWOT-AHP analysis, as one of the most powerful tools in identifying the problem environment, and Fuzzy ELECTRE analysis to evaluate the existing candidates to participate in the partnership using the criteria resulted from SWOT analysis. In first step, criteria set by an organization, as a case, to choose appropriate private sector were identified using SWOT method during various meetings with qualified experts. Then, the best choice was selected using ELECTRE method. Finally, obtained results were compared with the PROMETHE method. The results showed the effectiveness of our proposed method to select private partnerships especially positive and negative inter-organizational and outer-organizational factors significantly influence the private sector selection.