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In general, only six individual thrusters are required to perform 6 DOF (Degree Of Freedom) motion. Sometimes, however, more than six thrusters are used for 6 DOF motion for a variety of purposes. The over actuated systems can transit quickly from transient state caused by disturbance to steady state through the over actuated input. So in the underwater robot, the purpose of over actuated system is mainly used to maintain stable motion and position. And that systems are performed to obtain the optimal efficiency through the thruster force distribution. In this paper, we designed and fabrication the ROV (Remotely Operated Vehicle) for the basic study of over actuated underwater robot. It has 4 horizontal thrusters and 4 vertical thrusters. Using this system, we derived the thruster force distribution matrix for thruster allocation. Also, to check the kinetic characteristics of over actuated underwater robot before applying various controller, we performed the basic motion performance test and motion control test using the PD controller in the indoor engineering water basin.

Continued investment in Research and Development (R&D) by the government and corporate support played a major role in the rapid growth of the Republic of Korea. In 2017, the amount of R&D investment by the government accounted for 19.7 trillion Won (KRW), which is 4.7 % of the government’s budget. The government’s R&D budget is increasing by 2.5 % each year. We analyzed the outcomes of the projects, supported by the Busan regional companies conducted in 2016 to 2017. For a time series analysis, we gathered companies support amount by year, sales after company support, and material for employment. We used IBM’s Statistical Package for the Social Sciences (SPSS) 18 for correlation analysis. We confirmed the relationship between employment and the sales of the annual company support program.

The width and depth of excavation are important for the development of a water jet system for underwater surface excavation in the water. This is determined by the pressure distribution affecting the ground. Therefore, it is necessary to analyze the flow of the water jet, but it is difficult to grasp visually, and generally used sensors are difficult to use in water. To overcome this problem, the flow analysis was simulated by using Computational Fluid Dynamics(CFD), Particle Image Velocimetry(PIV) experiment was performed to confirm the accuracy of CFD and to visualize the nozzle flow. The CFD was simulated by using MIDAS NFX and various pressures of nozzle injection, velocity distribution and pressure distribution were analyzed. For the PIV experiment, the water jet system is installed at L22m x W3.5m x D3m water tank, and a 5W Nd-yag laser was installed at the surface of the water, and a high-speed camera was installed to capture the flow in the side observation field. And particles of 20 micrometer size were mixed in the water. In the results of the CFD simulations, the nozzle injection pressure which is the measurable velocity by the PIV system was selected, the nozzle flow was visualized and the velocity distribution was measured by using the PIV experiment. The velocity distribution measured by PIV is compared with the CFD - analyzed velocity distribution under the same conditions.

Reflecting the conditions and characteristics of Korea, the region's main industry is being developed to expand new job creation in the region and enhance the competitiveness of local industries. The local main business is supported to 63 main industries selected by region. The main industries in Busan include digital contents, intelligent machine parts, super precision convergence parts, mold heat treatment, and bio-health. In this study, the main industries of Busan region in 2016 conducted an analysis on the companies that support the intelligent machine parts industry. For the analysis, we collected data on the sales of supported companies, sales after business support, and employment growth. The analysis tool utilized IBM SPSS statistics 18. As a result, we confirmed the relationship between employment and sales according to support business programs. Based on the results of this study, it will be helpful for the task performing organization to identify the direction of the support program and the needs of the enterprise.