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A simultaneous optimization methodology is proposed considering both the structural and the process requirements for the weight minimization of laminated plates manufactured by the Resin Transfer Molding (RTM) process. The coupling between the structural performance and the process cost is considered through the investigation of state parameters in the RTM process. As the structural constraint, maximum allowable displacement or maximum allowable failure index of the structure under load is assigned. For the process constraint, maximum allowable mold filling time is given. A new approach to deal with design constraints without having to concern about the penalty parameters is suggested. The influence of design constraints on the optimal design configuration is investigated through parametric studies. As the optimization scheme, Genetic Algorithm (GA) is employed. To take into account the layer number variation, genetic operators such as the crossover and the mutation are modified. [ABSTRACT FROM PUBLISHER]

A solution scheme based on the maximum entropy method (MEM) for the solution of two-dimensional inverse heat conduction problems is established. MEM finds the solution which maximizes the entropy functional under the given temperature measurements. The proposed method converts the inverse problem to a nonlinear constrained optimization problem. The constraint of the optimization problem is the statistical consistency between the measured temperature and the estimated temperature. Successive quadratic programming (SQP) facilitates the numerical estimation of the maximum entropy solution. The characteristic feature of the proposed method is investigated with the sample numerical results. The presented results show considerable enhancement in resolution for stringent cases in comparison with a conventional method. [ABSTRACT FROM AUTHOR]

Contact angles of various monomers are measured by goniometer to calculate surface energies in order to select the monomer with highest surface energy. The highest surface energy is obtained with hexamethyl-disiloxane and is used in plasma coating the wood flour to improve its bonding and dispersion with the polypropylene (PP). The mechanical test results and SEM inspections indicate the good dispersion and the good compatibility between the wood flour and the PP. Also, this method is considered as a nontoxic process as compared to other chemical bonding method. [ABSTRACT FROM AUTHOR]

In this article, an inverse method for retrieving time- and space-varying heat flux on the surface of a three-dimensional slab with temperature-dependent thermophysical properties from temperature scanning on the opposite surface is investigated. The sequential gradient method, which implements the gradient method in a sequential manner, is employed to solve the nonlinear inverse heat conduction problem. To stabilize the solution algorithm, a cubicspline function is specified in space and a constant or linear function is specified in time without the use of the regularization term. The proposed method is verified with presented computational results for several cases. [ABSTRACT FROM AUTHOR]

Stiction in large area imprint lithography was studied by a microtribological approach. As imprinting area is expanded, fine aligning movement can be hindered by the adhesion or in-plane friction between the mold and the substrate. In this study, an analytical model for stiction force in the alignment process was proposed and evaluated by measuring the friction force between two plates mediated by a thin liquid film. Experimental verification was conducted for various geometries and surface conditions. Analytic and experimental results demonstrated that the meniscus force induced from surface tension was the most critical parameter affecting stiction in an alignment process. [ABSTRACT FROM AUTHOR]

A numerical study was performed on flow and heat transfer involving moving free surfaces that occurs in mold filling processes such as casting and injection molding. In these problems, the calculation domain changes continuously and the numerical treatment of the moving interface tends to cause artificial diffusion. Among the solution algorithms based on the Eulerian method, the volume-of-fluid (VOF) method was used because the method is simple and efficient in handling the complex flow patterns inside the cavity. To solve the transport equation of free surface without artificial smearing of the interface the baby-cell method was employed in the geometric reconstruction of the free surface. Furthermore, a predictor-corrector method was adopted in the time integration of volume-of-fluid (VOF) transport equation to increase the accuracy. The proposed scheme was verified through several benchmark problems. In order to show the capability of the proposed method, several three-dimensional mold filling processes were solved. The current algorithm was applied to the floating body problem. Three-dimensional floating body problems were tested. [ABSTRACT FROM AUTHOR]