In this paper, the goal is to produce a target wheel that integrates the plate and CPS wheel among the components of the drive plate mounted on an automobile engine. We attempted to develop a manufacturing process technology for incremental forming of a target wheel with the desired thickness by rotating a disk-shaped thin plate material and deforming the plate using a forming device and tools. Incremental forming system was set up by establishing a forming process and designing and manufacturing the device and parts required for processing. It consists of a total of 4 stages of molding process, and the optimal roll design that can properly collect materials to prevent cracks or reverse steps at each stage is primarily important. After manufacturing the prototype, a material test was performed to confirm whether the mechanical properties of the deformed part were sufficient to make gear teeth.

대기오염물질과 온실가스 배출량을 저감 시키기 위한 배기 후처리 장치에 대한 연구는 활발히 진행 중이지만 그 중 선박용 입 자상물질/질소산화물(PM/NOx) 동시저감 장치에서는 엔진에 미치는 배압 및 필터 담체 교체에 대한 문제가 발생하고 있다. 본 연구에서는 PM/NOx를 동시저감 할 수 있는 일체형 장치의 최적 설계를 위해 장치 내부 유동과 입·출구 압력을 통한 배압의 변화를 연구하여 적절한 기준을 제시하였다. Ansys Fluent를 활용하여 디젤미립자필터(DPF) 및 선택적촉매환원법(SCR)에 다공성 매체 조건을 적용하였고 공극률은 30 %, 40 %, 50 %, 60 % 및 70 %로 설정하였다. 또한, 엔진 부하에 따른 Inlet 속도를 경계 조건으로 7.4 m/s, 10.3 m/s, 13.1 m/s 및 26.2 m/s로 적 용하여 배압에 미치는 영향을 분석하였다. CFD 분석 결과, 장치의 입구 온도 보다 입구 속도에 따른 배압의 변화율이 크고 최대 변화율은 27.4 mbar였다. 그리고 모든 경계 조건에서의 배압이 선급 기준인 68 mbar를 초과하지 않았기 때문에 1800 kW 선박에 적합한 장치로 평가 되었다.

Bypass line과 Catalyst를 공간적으로 결합한 Bypass 일체형 탈질설비를 제안하였다. 탈질설비 내부에 설치되는 Bypass의 개폐장치 의 형태에 따른 Catalyst로의 유동 변화를 확인하기 위하여 상용프로그램인 Ansys Fluent를 사용하여 탈질설비를 모델링하고 시뮬레이션을 구성하였다. 탈질설비 내의 Catalyst로 인한 계산시간과 Mesh의 수를 줄이기 위해 Porous media방식으로 Catalyst를 모델링하였다. Catalyst로 의 입구각도와 Bypass 개폐장치의 크기를 변화시키면서 시뮬레이션을 수행하고 시뮬레이션의 결과로 Catalyst로의 유동 평균속도와 균일도의 변화를 확인하였다.

Electrochromic devices (ECDs) have been drawing great attention due to their high color contrast, low power consumption, and memory effect, and can be used in smart windows, automatic dimming mirrors, and information display devices. As with other electronic devices such as LEDs (light emitting diodes), solar cells, and transistors, the mechanical flexibility of ECDs is one of the most important issue for their potential applications. In this paper, we report on flexible ECDs (f-ECDs) fabricated using an all-in-one EC gel, which is a mixture of electrolyte and EC material. The f-ECDs are compared with rigid ECDs (r-ECDs) on ITO glass substrate in terms of color contrast, coloration efficiency, and switching speed. It is confirmed that the f-ECDs embedding all-in-one gel show strong blue absorption and have competitive EC performance. Repetitive bending tests show a degradation of electrochromic performance, which must be improved using an optimized device fabrication process.

Thermal external cracks can be initiated at the parting line, which is the dividing line that splits the core and cavity halves of a molded exhaust manifold-turbine housing. The fatigue cracks are often resulted from hot-cold cycle loads called by thermal shock cycles, and are accompanied by large plastic strains. This paper investigated the effects of parting lines of the integrated exhaust manifold-turbine housing and compared the magnitude of plastic strains directly correlated to low cycle fatigue damages or cracks. The finite element results showed that the plastic strains at runner junctions including parting line was calculated by 0.68%, which is approximately 60% higher than that of the turbine housing considering no parting line. So, if the analysis target is less than 0.50 % of plastic strain amplitude, the fatigue damages or cracks could be expected by considering the parting lines in integrated exhaust manifold-turbocharger.

Eutrophication and algal blooms can lead to increase of taste and odor compounds and health problems by cyanobacterial toxins. To cope with these eco-social issues, Ministry of Environment in Korea has been reinforcing the effluent standards of wastewater treatment facilities. As a result, various advanced phosphorus removal processes have been adopted in each wastewater treatment plant nation-widely. However, a lot of existing advanced wastewater treatment processes have been facing the problems of expensive cost in operation and excessive sludge production caused by high dosage of coagulant. In this study, the sedimentation and dissolved air flotation (SeDAF) process integrated with sedimentation and flotation has been developed for enhanced phosphorus removal in wastewater treatment facilities. Design and operating parameters of the SeDAF process with the capacity of 100 m3/d were determined, and a demonstration plant has been installed and operated at I wastewater treatment facility (located in Gyeonggi-do) for the verification of field applicability. Several empirical evaluations for the SeDAF process were performed at demonstration-plant scale, and the results showed clearly that T-P and turbidity values of treated water were to satisfy the highest effluent standards below 0.2 mg/L and 2.0 NTU stably for all of operation cases.

To remove phosphorus from the effluent of public wastewater treatment facilities, hundreds of enhanced phosphorus treatment processes have been introduced nationwide. However, these processes have a few problems including excessive maintenance cost and sludge production caused by inappropriate coagulant injection. Therefore, the optimal decision of coagulant dosage and automatic control of coagulant injection are essential. To overcome the drawbacks of conventional phosphorus removal processes, the integrated sedimentation and dissolved air flotation(SeDAF) process has been developed and a demonstration plant(capacity: 100 m3/d) has also been installed. In this study, various jar-tests(sedimentation and / or sedimentation·flotation) and multiple regression analyses have been performed. Particularly, we have highlighted the decision–making algorithms of optimal coagulant dosage to improve the applicability of the SeDAF process. As a result, the sedimentation jar-test could be a simple and reliable method for the decision of appropriate coagulant dosage in field condition of the SeDAF process. And, we have found that the SeDAF process can save 30 – 40% of coagulant dosage compared with conventional sedimentation processes to achieve total phosphorus (T-P) concentration below 0.2 mg/L of treated water, and it can also reduce same portion of sludge production.

Recently, electrochromic devices (ECDs) have gathered increasing attention owing to their high color contrast and memory effect, which make them highly applicable to smart windows, auto-dimming mirrors, sensors, etc. Traditional ECDs have a sandwich structure that contains an electrochromic layer between two ITO substrates. These sandwich-type devices are usually fabricated through the lamination of two electrodes and followed by the injection of a liquid electrolyte in the inner space. However, this process is sometimes complex and time consuming. In this study, we fabricated ECDs with a lateral electrode structure that uses only an ITO substrate and an all-in-one electrochromic gel, which is a mixture of electrolyte and electrochromic material. Furthermore, we investigated the EC properties of the lateral-type device by comparing it with a sandwich-type device. The lateral-type ECD shows strong blue absorption as the applied voltage increases and has a competitive coloration efficiency compared to the sandwich-type device.

A safety lancet was developed in this study. The development process consists of a conceptual design, mock-up tests, performance evaluation, verification, validation for medical device certification and mass production preparation. It is designed as a single unit which makes it possible to use more convenient. It is also designed as disposable product which cannot be reused or recycled structurally. The developed safety lancet can prevent the secondary infection by needle stick injury or reuse. Biocompatibility and physico-chemical characteristics were passed in KTL(Korea Testing Laboratory). Validation of gamma sterilization of packing materials was passed in professional company for mass production.

도로 교통사고로 인해 매년 5천여 명의 사망자와 30만여 명의 부상자가 발생하고 있다. 도로 교통사고는 도로이용자-자동차-도로 인프라 측면에서의 결함에 따른 것으로, 특히 도로 인프라 가운데 도로교통 안전시설은 도로 자체의 선형 결함 등을 보완하고 야간 등 비정상적인 도로환경에서 운전자의 안전을 보장하기 위해 설치되며 매년 설치물량뿐만 아니라 시설 자체의 성능도 지속적으로 발전되고 있다. 본 연구는 도로교통 안전시설 가운데 야간 및 악천후 시 도로 시인성을 극대화하는 시설인 조명시설과 차량이 차도를 벗어난 경우에 운전자의 안전을 보장하는 차량방호 안전시설이 일체화된 시설물에 대한 성능검증을 위한 연구이며 현재 기존 연구 및 향후 연구계획에 대한 추진 시나리오를 정립하는 단계에 있다. 이를 위해 조명시설이 갖추어야 하는 시인 성능(휘도, 균제도), 차량방호 안전시설이 갖추어야 하는 방호성능(탑승자 방호, 차량 충돌 후 거동, 구조물 변위)에 대한 성능실험을 수행할 계획이다. 본 연구에서 개발코자 하는 조명-차량방호 일체형 안전시설은 첫째 도로 폭이 협소하여 충분한 시설한계(Right-of-Way)가 확보되기 곤란한 지점이나 교량 등 특수구간, 둘째 조명의 높이를 운전자의 눈높이에 맞추어 연속적인 주행환경 확보가 용이하고 도로 생태환경 보호에 유리한 점, 셋째 조명시설과 방호시설을 일체화함으로써 시선유도효과를 극대화하고 시설 간 간섭최소화를 통해 미관확보가 가능하다는 장점이 있다. 본 연구를 통해 도로교통 안전시설 각각의 성능발전뿐만 아니라 상호간 물리적 결합 등을 통해 도로이용자에게 우수한 주행환경을 제공할 수 있는 기회를 확대할 수 있으며 국내 안전시설 기술의 해외진출 시에도 타국제품 대비 상대적인 우수성을 확보할 수 있는 특화사항으로 발전될 수 있을 것으로 본다.

This research focuses on the condition of the coveralls that automobile maintenance workers wear. The objective of this survey is to conduct a thorough analysis on the quality of the coveralls and put forth suggestions for improving their quality. The research data were collected through interviews and the results are as follows. The participants in this research engage in a variety of types of maintenance work including oil changes and overall system checks and they usually wear extra-large-sized coveralls. The coveralls are generally worn during the winter for warmth and the company handles all purchasing and maintenance of the work clothes. Participants mentioned that certain parts of the clothes where they bend and stretch are cumbersome and areas around the knees and arms become easily tainted. They have also reported that although the coveralls are necessary, they are for the most part dissatisfied when it comes to the materials, design, and color. The participants have suggested that new coveralls would help to increase their work efficiency. As a result, it is concluded that the coveralls require much more development to meet the workers’ needs and improvements need to be made on the functionality, aesthetics, and symbolic aspects of the design.