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Recently, a coil gun was brought to the attention of engineering community as electromagnetic alternative to the chemical launchers. Various studies were performed on coil gun systems focused on achieving the high muzzle velocity in military applications and for satellite launching. Most of these studies focused on improvement of muzzle velocity via increase in the size of the coil gun. Present paper describes the process of design optimization where the size of the coli gun system is restricted. The design of experiment approach utilizes the orthogonal array table that reduces the required number of experiments. The design of experiment is carried out with a commercial PIAnO tool, where the finite element analysis is performed at each experimental point. Then, Kriging model is created to achieve accurate approximation in problems of many design variables or strongly nonlinear model. The coil gun is optimally designed using an evolutionary algorithm (EA) as optimization technique. In order to verify the improvement of muzzle velocity by optimal design, the prototypes of coil gun system are manufactured and the experiments to launch the projectile are performed.

The research is concerned with the process of regional growth. The purpose is two-fold: (i) to analyze the relations between national aggregate efficiency and interregional income equality in the regional policy decision-making process; and (ii) to explain the historic change in the levels of interregional income inequality in the United States. The study gives particular attention to two different political-economic systems: a planned economy and a free market system. The analysis of regional growth in a planned economy shows the relations between two regional policy goals (i.e., efficiency and equality) through both static and dynamic analyses. The important policy variable adopted here is the regional allocation of investment. This study departs from the existing literature by dropping faulty assumptions from neoclassical regional economic growth theory such as: (i) constant returns to scale; (ii) identical production functions; and (iii) a two-region economy. The static analysis presents various relations between efficiency and equality such as trade-off, non-trade-off and mixed-relations. The dynamic analysis concludes that the two goals conflict in most cases, even though there might be some fluctuation on the short-term planning horizon. The analysis of regional growth in a free market system deals with the following question: Why do regional income inequalities decrease (or increase) as the economy develops? The study shows several interesting results. First, regional income inequalities in the U.S. have been decreasing over time except for the short-time effect of the Great Depression. This finding is quite different from Myrdal's expectation and Williamson's inverted-U hypothesis. Second, neoclassical growth theory as a theoretical rationale for interregional income convergence has a limited predictive accuracy. Both empirical and theoretical analyses indicate that interregional factor flows neither ensure full convergence nor full divergence. Finally, it