• Industrial Engineering and Management Systems
• /
• 제16권1호
• /
• pp.22-43
• /
• 2017

It is urgently-needed to construct a green supply chain (GSC) from collection of used products through recycling of them to sales of products using the recycled parts. Besides, it is necessary to consider the uncertainty in product demand as a risk in a GSC. This study proposes the optimal operations for a GSC with a retailer and a manufacturer. A retailer pays an incentive for collection of used products from customers and sells a single type of products in a market. A manufacturer produces the products ordered by the retailer, using recyclable parts with acceptable quality and compensates the collection cost of used products as to the recycled parts. This paper discusses the following risk attitudes: risk-neutral attitude, risk-averse attitude, and risk-prone attitude. Using mean-variance analysis, the optimal decisions for product order quantity, collection incentive, and lower limit of quality level, in the decentralized GSC (DGSC) and the integrated GSC (IGSC) are made. DGSC optimizes the utility function of each member. IGSC does that of the whole system. The analysis numerically investigates how (i) risk attitude and (ii) quality of recyclable parts affect the optimal operations. Supply chain coordination between GSC members to shift IGSC from DGSC is discussed.

• 청정기술
• /
• 제14권4호
• /
• pp.232-241
• /
• 2008

EU의 WEEE 지침에는 전기전자제품의 생산자들이 반드시 달성하여야 하는 재활용률과 재생률의 목표치가 설정되어 있다. 본 연구에서는 전기전자제품의 생산자들이 개발되는 제품의 재활용가능률과 재생가능률을 산정해 보는데 필요한 부품과 소재들의 재활용률과 재생률의 기준을 만들어 보았다. 먼저 전기전자제품의 재활용공정과 부품 및 소재별 재활용 및 재생특성을 분석해 보았으며, 유럽 현지 업체들의 처리결과에 따른 재활용률과 관련된 자료들을 조사하여 분석하였다. 이러한 결과로 작성된 재활용률과 재생률 DB는 유럽의 전문가의 의견을 반영하여 개선하였다.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 1994년도 추계학술대회 논문집
• /
• pp.918-923
• /
• 1994

For the improvement of productivity, the reduction of cost and time for manufacturing is mandatory, especially in the field of electronic industry. The study is concemed with a practical means of systematic assistance to formability estimation and selection of reliable design specification for electronic sheet metal parts. The objective of this research work is to develop a simulation system which helps to analyze the target processes with the finite element method and to acquire available design data quickly and exactly and exactly. The simulation system developed in the study consists of design verification, selection of optimal combination of parameters, knowledge acquisition and graphical user interface(GUI). Design verification is automatically carried out by using the finite element method. A data base management system and nomograms are utilized for knowledge acquistion. The developed system has been applied to some major sheet metal forming operations such as flanging, embossing, bending and blanking. According to the simulated results, the validation of the target processes has been confirmed. Analysis data, estimation rules of formability and graphical representation of the analysis have been employed for the designer's understanfing and evaluation, thus providing a practical means of robot design and evaluation of formability for production electronic sheet metal parts.

• 한국군사과학기술학회지
• /
• 제23권4호
• /
• pp.319-327
• /
• 2020

In this study a methodology to evaluate fatigue life of the electronic parts for the fighter radar unit under random vibration loading is presented. To do this, one parameter for the 3-σ RMS quation of Steinberg fatigue model is modified to come up with a printed circuit board(PCB) with multiple electronic parts, while fundamental frequency and dynamic deflection of the PCB are calculated from a MATLAB based finite element computer code. For the RIFA structure selected in this study, the 3-σ RMS fatigue limit displacement is reduced to 0.741 times as much as the Steinberg model. This investigation allows to assess the life of multiple electronic parts mounted on the PCB with reinforced metal cover/body showing non-sinusoidal deflection patterns.

• 센서학회지
• /
• 제17권5호
• /
• pp.338-345
• /
• 2008

Steel bearing balls are important component in machines having moving parts. In this paper we describe a vision-based automatic inspection system designed for sensing defects on the surface of steel bearing balls. The system has a camera looking down over a rail on which balls roll. Two mirrors are installed at both sides of the rail so that the side parts of a ball can be well inspected. The entire ball surface can be sufficiently seen by taking three images at $120^{\circ}$ rotation interval. Defects are detected by thresholding the difference image between an image captured and the reference image of a good ball.

• 대한안전경영과학회지
• /
• 제12권2호
• /
• pp.133-138
• /
• 2010

The environmental regulation of a product is a global trend. The environmental regulation directives such as RoHS, WEEE, ELV and REACH have impacted Korean export-oriented auto parts manufacturer and affects the export of the product to aboard. In electronics manufacture and auto parts manufacturer, there are different systems for environmental regulation compliance. Nowadays the automotive mechatronics parts in a car are increasing. The HEV and intelligent car will need more mechatronics parts. It is necessary to apply the environmental regulation system of electronics to the automotive parts. In this paper, we proposed the application of PDX standard used in electronic industry to the BOM of the auto parts manufactures and showed an example of generated BOM for selected auto part using PDX. The PDX-based BOM can be used for the recording of environmental substances of the automotive mechatronics part and help the collaboration across auto parts manufactures in accordance with environmental regulation.

• 전기학회논문지
• /
• 제66권12호
• /
• pp.1810-1814
• /
• 2017

This paper develops an approach to the algorithm of Gait pattern Analysis and step measurement with Multi-Pressure Sensors. The process of gait consists of 8 steps including stance and swing phase. As 3 parts of foot is supporting most of human weight, multiple pressure sensors are attached on the parts of foot: forefoot, big toe, heel. As 3 parts of foot is supporting most of human weight, multiple pressure sensors are attached on the parts of foot: forefoot, big toe, heel. normal gait proceed from heel, forefoot and big toe over time. While normal gait proceeds, values of heel, forefoot and big toe can be changed over time. So Each values of pressure sensors over time could discriminate whether it is normal or abnormal gait. Measuring Device consists of non-inverting amplifiers and low pass filter. Through timetable of values, normal gait pattern can be analyzed, because of supported weight of foot. Also, the peak value of pressure can judge whether it is walking or running. While people are running, insole of shoes is floating in the air on moment. Using this algorithm, gait analysis and step count can be measured.

• 대한기계학회논문집
• /
• 제13권4호
• /
• pp.771-779
• /
• 1989

본 연구에서는 기판의 양면에 부품이 SMT방법으로 탑재되어 있는 경우에 기판사이에 형성되는 유동채널에서의 열전달 및 유동특성을 연구하였다.

• 한국산업융합학회 논문집
• /
• 제25권2_1호
• /
• pp.177-184
• /
• 2022

The automatic defect sorting function of machinery parts is being introduced to the automation of the manufacturing process. In the final stage of automation of the manufacturing process, it is necessary to apply computer vision rather than human visual judgment to determine whether there is a defect. In this paper, we introduce a deep learning method to improve the classification performance of typical mechanical parts, such as welding parts, galvanized round plugs, and electro galvanized nuts, based on the results of experiments. In the case of poor welding, the method to further increase the depth of layer of the basic deep learning model was effective, and in the case of a circular plug, the surrounding data outside the defective target area affected it, so it could be solved through an appropriate pre-processing technique. Finally, in the case of a nut plated with zinc, since it receives data from multiple cameras due to its three-dimensional structure, it is greatly affected by lighting and has a problem in that it also affects the background image. To solve this problem, methods such as two-dimensional connectivity were applied in the object segmentation preprocessing process. Although the experiments suggested that the proposed methods are effective, most of the provided good/defective images data sets are relatively small, which may cause a learning balance problem of the deep learning model, so we plan to secure more data in the future.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2009년도 춘계학술대회 논문집
• /
• pp.55-56
• /
• 2009

A light guiding plate (LGP) with nanometer-sized patterns was fabricated by injection molding method which employed electrically healed mold and the transcription of injection-molded parts was investigated. A Ni stamper was fabricated using MEMS technology. The Ni stamper was then installed in a movable heated core which is a key part of the mold. Using this mold, injection-molded plastic LGP parts were manufactured at different mold temperatures and the effect of the temperature on the transcription of the parts was investigated.