In this study, We designated the injection molded plug housing for charging electric vehicles as a research subject. And we analyzed the effect of Rib design on the quality of injection molded products. First, we used the Taguchi method to derive optimal conditions for rib design. The factors were set as the Thickness of the rib, the Height of the rib, and the Radius of the rib. Each factor consisted of 5 levels and generated conditions for a total of 125. We performed an injection molding analysis and confirmed significant factors affecting the deformation of injection molded products through ANOVA. Based on this, the 25th design detail was selected as the optimal condition. In addition, We compared the results of the molding analysis with the molded products that did not design ribs. We confirmed that the molded product designed with ribs under optimal design detail improved the deformation amount by 22.22% and the residual stress by 8.35%, compared to the molded product not designed with ribs.

For a plastic diffusion lens to uniformly diffuse light, it is important to minimize deformation that may occur during injection molding and to minimize deformation. It is essential to control the injection molding condition precisely. In addition, as the number of meshes increases, there is a limitation in that the time required for analysis increases. Therefore, We applied machine learning algorithms for faster and more precise control of molding conditions. This study attempts to predict the deformation of a plastic diffusion lens using the Decision Tree regression algorithm. As the variables of injection molding, melt temperature, packing pressure, packing time, and ram speed were set as variables, and the dependent variable was set as the deformation value. A total of 256 injection molding analyses were conducted. We evaluated the prediction model's performance after learning the Decision Tree regression model based on the result data of 256 injection molding analyses. In addition, We confirmed the prediction model's reliability by comparing the injection molding analysis results.

In this study, we used a numerical analysis program to study the molding conditions that affect the flow rate at the time of injection, using a spiral mold, which is mainly used for the evaluation of the flow rate of plastic resin. The mold temperature, melt temperature, and flow rate are composed of experimental factors. The three plastic forming factors were divided into five to six levels each. Since then, changes in the flow rate temperature were analyzed as the level of each forming factor increased. Experiments showed that all three forming factors increased the filling length of the spiral mold and the temperature of the flow front by a total of 34.53°C, melt temperatures increased the temperature of the flow front by a total of 34.53°C, the temperature increased by the flow rate was 23.5°C, and the temperature increased by the mold temperature was 1.99°C. It was shown that the melt temperature was the largest, followed by the flow rate and mold temperature. It was also possible to check the effect of plastic forming factors on the speed of the flow front.

우리나라의 폐기물 발생량은 인구증가, 경제성장, 삶의 질 향상에 의해 꾸준히 증가하고 있으며, 증가하는 폐기물에 ‘자원화’로 인식을 전환시켜 재사용, 재활용하기 위한 다양한 정책을 추진중에 있다. 또한 자원화 방법 외에 소각 등의 처리를 한 후 매립장에 매립하고 있다. 자원화 방법 외에 소각과 매립의 방법으로 발생되는 폐기물을 적정하게 처리하기 위해서는 환경기초시설의 설치가 필수적이고, 환경기초시설(매립시설, 소각시설)의 설계 및 용량을 결정하기 위해서는 발생되고 있는 폐기물에 대한 정확한 분석과정이 우선시 되어야 하며, 이 과정은 매우 중요하다고 할 수 있다. 더욱이 소각시설의 경우 대기오염, 악취, 자원에 대한 낭비 등의 문제를 야기할 가능성이 높기 때문에, 소각시설의 적정 운전을 위하여 폐기물에 대한 물리･화학적 분석과 발열량에 대한 기초자료는 소각시설 설계 시 매우 중요 인자로 활용되고 있다. 하지만 소각시설 설계 시 고려되었던 폐기물에 대한 기초 자료로 설정한 소각시설의 운전조건이 실제로 소각시설이 운영되었을 때를 얼마만큼 유지하고 있는지는 지속적인 조사가 필요할 것이다. 왜냐하면 시간이 지나면서 사람들의 소비패턴이 변하며, 발생되는 폐기물의 양과 성분도 변하기 때문이다. 이에 본 연구에서는 인구 22만 명 정도의 중소도시를 대상으로 소각시설이 운영되고 있는 지역을 선정하였고, 선정된 지역의 과거부터 현재까지의 발생되고 있는 생활폐기물의 특성을 분석하고자 하였다. 생활폐기물의 변화특성을 조사･분석하기 위하여, 겉보기밀도, 삼성분분석, 발열량분석 등을 수행하였다. 향후 이 자료는 충주시에서 소각시설 운영을 위한 최적의 운전인자를 도출하는데 중요 자료로 활용될 수 있으며, 폐기물관리 정책수립 및 처리에 기초자료로 제시하고자 한다.