본 연구에서는 20,000 톤급 해양플랜트 상부구조물(Topside)의 플로트오버 설치작업을 위해 개발된 수동형 갑판 지지 프레임 (Deck support frame)의 구조설계에 대해 다양한 실험계획법을 이용한 최소중량설계와 민감도 평가의 비교연구를 수행하였다. 수동형 갑판 지지 프레임의 주요 구조부재의 두께 치수 변수는 설계인자로 고려하였고, 응답치는 중량과 강도성능으로 선정하였다. 최소중량설계와 민감도 평가의 비교연구에 사용한 실험계획법은 직교배열설계법, Box-Behnken 설계법, 그리고 Latin hypercube 설계법이다. 실험계획법의 설계공간 탐색의 근사화 성능을 평가하기 위해 반응표면법을 각 실험계획법 별로 생성하여 근사화 정확도 특성을 검토하였다. 또한 최소 중량설계를 위해 최상 설계안의 결과로 부터 실험계획법의 특성에 따른 수치계산 비용, 중량감소 효과 등을 평가하였다. 수동형 갑판 지지 프레임의 구조설계에 대해 Box-Behnken 설계법이 가장 적합한 설계 결과를 나타내었다.

As the demand of fossil fuel has been increased, meeting future will be faced with exhausted non-renewable energy generation. In addition, there is a lot of expectation that fossil fuel resources are expected to get depleted in the end of century. Piezoelectric energy harvesting technology has significant advantages over other renewable energy sources such as solar panel, wind and geothermal energy. By using the pressure of vehicles, the piezoelectric energy transforms to electric energy by deformation of paving materials. There are many studies about this theme, only a few researches have been conducted on-site. It means that piezoelectric harvester is not available for roadway. Therefore, it is necessary to make it better a research framework that is available technology of piezoelectric materials and paving materials. The piezoelectric generator is tested before piezoelectric harvester manufacture for roadway. Each piezoelectric generator produces 9.38[mW/cm²] and piezoelectric harvester is manufactured by the number of 85 the piezoelectric generator. This harvester size has 50*20*9cm3 which is considered for wheel path of vehicle. When the chosen vehicle (about 2 ton) pass this harvester, the amount of electric energy is 255[W/m²] under 2[mm] of deformation and 30[km/h] of velocity. In this situation, the gathered energy is multiplied the maximum of voltage and electric current then divide it for the area of harvester. The test result is the temperature difference between the inside and outside after the thermal insulation coating process. When the external surface temperature is increased to 180 degrees, the internal temperature is kept 80 degrees even after about 30 minutes, indicating that the internal materials are protected from heat. In spite of many advantages with piezoelectric harvesting system, it is very hard to fit between roadway and harvester because of pavement damage. Most of paving material has a strong thickness. In this study, instead of asphalt and concrete pavement, the paving material is compound of poly-urethane to protect rutting and damage. To analysis for behavior, test is conducted by 90,000 times of wheel load on the pavement. The red line on the graph is commonly used asphalt pavement and the green one is polyurethane pavement. As it seemed that polyurethane pavement shows that the depth from wheel load is over 5 times better performance compared with asphalt pavement. Construction design is first of all, cutting off asphalt which is established before, then set up the tenth of piezoelectric harvesters, twenty fourth of road markers is installed into the roadway. Before filling up to space with polyurethane materials, wire arrangement and connect to controller. Each harvester is connected with controller that makes a signal for voltage, temperature sensor, water leak sensor. In order to use electric energy by harvester, road markers are selected, which each harvester has three of road markers. A circuit for lighting the light emitting device using the output of the harvester installed in the rest area was designed and manufactured. Basically, a circuit is configured to light up the harvester output, and a commercial power supply can be used in case the output of the harvester is reduced due to the durability thereof, and a controller is manufactured for each harvester to connect the road markers. Key Words: Piezoelectric Harvester