The outcome of the ab-initio crystal structure solution process by Direct Methods depends on not only the quality of the extracted integrated intensities but also the experimental resolution [1]. In fact, the limited experimental resolution distorts the Fourier synthesis even at atomic resolution: when the resolution is larger than 1 Å, the electron density map is an imperfect representation of...

in this work, the optimization calculations were carried out on quetiapine hemifumarat, 4, and its analogues, 1-5. these calculations were carried out using the b3lyp/6-31g(d) level of theory. the dft calculations clarified a boat structure for dibenzothiazepine moiety of the molecule which piperazine moiety has a chair conformation. thermal energies (e), enthalpies (h), and free energies (g) o...

The prevalent strategy in the topology optimization phase is to select a subset of members existing in an excessively connected truss, called Ground Structure, such that the overall weight or cost is minimized. Although finding a good topology significantly reduces the overall cost, excessive growth of the size of topology space combined with existence of varied types of design variables challe...

We describe a family of global optimization procedures that automatically decompose optimization problems into smaller loosely coupled problems. The solutions of these are subsequently combined with message passing algorithms. We show empirically that these methods produce better solutions with fewer function evaluations than existing global optimization methods. To develop these methods, we in...

In this paper, a methodology is presented for optimum shape design of double-layer grids subject to gravity and earthquake loadings. The design variables are the number of divisions in two directions, the height between two layers and the cross-sectional areas of the structural elements. The objective function is the weight of the structure and the design constraints are some limitations on str...

this paper focuses on the optimization of initiating dimensions of groove bearing in association with de- sired design of vehicle’s front structure which is made up of low carbon steels in the case of frontal collision. axial bearing analysis is done numerically using nonlinear finite element code ls-dyna. in this analysis, changes of two main parameters including measure of energy absorption o...