The sewer layout in flat areas significantly influences the construction and operational costs as well as reliability of the network performance. To find an optimum DESIGN of sewer networks for flat areas, this study presents a MULTI-OBJECTIVE optimization problem with the objective functions of 1- the cost and 2- the reliability. The reliability criterion is defined as the effect of a clogging in a sewer on its upstream population. To solve the problem, the NSGA-II Algorithm is coupled to two self-adaptive DESIGN algorithms for generating the layout and sizing of sewers. A case study is solved using the proposed model to demonstrate its application and advantages.

Constructal DESIGN, finite element method and exhaustive search are applied to analyze different arrangements of steel plates with rectangular or trapezoidal stiffeners. As performance parameters, the maximum deflection and maximum von Mises stress are considered. A non-stiffened plate adopted as reference is studied together with 25 plates with rectangular stiffeners and 25 plates with trapezoidal stiffeners. The results show that trapezoidal stiffeners are more effective in minimizing the maximum deflection in comparison with rectangular stiffeners. However, regarding the minimization of stress, the rectangular stiffeners normally present better performance. When both performance parameters are concomitantly considered, a slight advantage of 4. 70% for rectangular geometry is identified.

In this paper, a systematic approach is considered to DESIGN an optimal hypersonic Nozzle of a shock tunnel. After assigning the requirements and accomplishment of conceptual and preliminary DESIGN phases, a modern optimization strategy based on genetic algorithm and a CFD solver has been used to fine tune the nozzle convergent divergent contour. In this way, parameterization of the overall nozzle contour was done with a few control points and a Bezier curve. This arrangement showed a good flexibility to generate appropriate curves for nozzle shape. DESIGN objectives were evaluated with a N-S viscous solver with a two equation turbulence model. Three objective functions were scalerized in a term with summation of weighted parameters: minimum total pressure loss, Mach number uniform distribution along test section and minimum axial flow deviation. A number of geometrical and physical constraints such as nozzle length, throat area, inlet and outlet diameters and inlet boundary conditions were also considered and finally, an optimized nozzle contour showed a significant improvement of about 3% in quality of the Mach 6 flow in the test section.

Present study describes the approach of applying MULTI-OBJECTIVE optimization method to optimizing of sheet metal forming Die. In many studies, Finite element analysis and optimization technique have been integrated to solve the optimal process parameters of sheet metal forming by transforming MULTI-OBJECTIVE problem into a single-objective problem. This paper aims to minimize the objective functions of fracture and wrinkle simultaneously. DESIGN variables are blank-holding force and draw-bead geometry. Response surface model has been used for DESIGN of experiment and finding relationships between variables and objective functions. In DESIGNing of experiments v-optimal DESIGN has been used which minimizes the average prediction error variance, to obtain accurate predictions. Forming Limit Curve has been used to define the objective functions. Finite element analysis applied for simulating the forming process. Proposed approach has been investigated on a drawing part and experimentally verified. The optimal DESIGN showed a good agreement with experimental species. It has been observed that proposed approach provides aneffective solution to DESIGN of process parameters without a the ‘trial and error’ procedure.

Intracytoplasmic sperm injection (ICSI) is one of the most successful techniques of Assisted Reproductive Technology (ART) and is mostly in use for the treatment of infertility with male factors. In this method, before injecting sperm into the intracytoplasmic of the oocyte, cumulus cells around the oocyte must be stripped to facilitate the injection process. To achieve this, both enzymatic and mechanical methods are used in embryological laboratories for denudation, which has major deficiencies, including the possibility of damaging the oocyte prior to the injection process. In this research, a microfluidic-based device is introduced for the separation of cumulus cells around the oocyte with minimum manual operations. The results prove high efficiency, and non-destructive denudation of the oocyte with the reduced amount of culture medium leads to the low-cost preparation process of oocytes. The process can also be integrated with ICSI chips under development and will be reported shortly.

A multiobjective security game problem with fuzzy payoffs is studied in this paper. The problem is formulated as a bilevel programming problem with fuzzy coefficients. Using the idea of nearest interval approximation of fuzzy numbers, the problem is transformed into a bilevel programming problem with interval coefficients. The Karush-Kuhn-Tucker conditions is applied then to reduce the problem to an interval multiobjective single-level problem. It is shown that the solutions of this problem are obtained by solving a single-objective programming problem. Validity and applicability of the method are illustrated by a practical example.

Generally, an engineering DESIGN problem has multiple objective functions. Some of these problems can be formulated as multiobjective geometric programming models. On the other hand, often in the real world, coefficients of the objective functions are not known precisely. Coefficients may be interpreted as fuzzy numbers, which lead to a multiobjective geometric programming with fuzzy parameters. In this paper, we solve the multiobjective geometric programming problem with fuzzy parameters by applying a linear ranking function. The linear ranking function is used to compare fuzzy numbers. Finally, a numerical example is given.