• 한국기계가공학회지
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• 제7권1호
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• pp.22-31
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• 2008

The operating window method is a novel approach in quality improvement. But it has not received deserved attention in academic research. If a critical factor for competing failure modes can be identified, the probability of failure can be reduced by widening the operating window of this factor. Traditional SN ratio for the operating window advocated by Taguchi has a critical shortcoming, which has been derived under the assumption that failure rates are determined by the operating window factor only. A new metric for robustness is given for the operating window method, which has relaxed the restrictive assumption of Taguchi's SN ratio. And procedures for determining optimal conditions based on the new metric is presented. The effectiveness of the proposed approach over the traditional practice is tested with the aid of a wave soldering process.

• 동력기계공학회지
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• 제9권2호
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• pp.73-80
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• 2005

Both theoretical and experimental investigations were conducted to analyze defrosting behavior of a window heater operating in the low outdoor temperature($-20^{\circ}C$). To achieve this purpose, first a warm-chamber experiment($23^{\circ}C$) was performed to measure inner and outer surface temperature of the rear window(heated by the electric heater supplying 195 W) as functions of both time and position. Secondly, a cold chamber experiment was made to continuously record defrosting process of the frosted window. From the comparisons of the two experimental results, it was found that there was a similarity between the spatial distributions of both temperature and remaining frost. Thus, the temperature data from the warm-chamber experiments can be utilized to predict an expected zone covered with remaining frosts, and this approach can also be adopted in the inspection process in order to economically guarantee optimized performance of the window heater. Finally, an analytical model based on one-dimensional, steady-state heat transfer theories was proposed and successfully predicted the outer surface temperature of the rear window surrounded by cold air($-20^{\circ}C$) for the given operating conditions(heater power, inside and outside heat transfer coefficients, and surrounding air temperature, etc.).

• Elastomers and Composites
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• 제54권4호
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• pp.351-358
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• 2019

To evaluate the aging of a rubber pad in power window switch which is the part of a vehicle, the accelerated thermal aging test of rubber pad material is performed. Finite element analysis was performed using the nonlinear material constants of the rubber pad to calculate the operating force, and the Arrhenius relationship was derived from the aging temperature and time. The aging test was performed at 150, 180, 210, or 240 ℃ for 1 to 60 days. When the operating force of the rubber pad is changed by 10% from the initial value, the service life is expected to be 113 years, which is much longer than the life of the vehicle. This indicates that the aging life of the rubber pad is sufficiently safe and the operating force of the rubber pad during the life of the vehicle (20 years) was decreased by approximately 8.4%. By examining the correlation between the shear elastic modulus and operating force calculated from finite element analysis under each aging test condition, the changes in the operating force of the rubber pad and the shear elastic modulus showed good linear relationship. The aging life could be predicted by the change in shear elastic modulus and a process for predicting the aging life of automotive power window switch rubber pad parts is described herein.

• 생물환경조절학회지
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• 제10권1호
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• pp.42-49
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• 2001

온실의 환기제어시 외기의 온도와 풍속변화에 보다 유연하게 대처하면서 온도제어성능을 향상시키기 위하여 퍼지제어 알고리즘을 수립하고 제어실험을 실시하였다. 환기창을 열어 환기 시 온실의 실내온도 변화는 실내외온도차 및 외기 풍속의 세기와 방향에 영향을 받으므로 실내온도 기울기를 퍼지변수의 하나로 취급하여 퍼지변수의 수를 줄였다. 설정온도가 일정할 때 제어오차의 증분은 실내온도 증분과 같으므로, 전건부 퍼지변수는 제어오차(실내온도-설정온도)와 그 증분으로 결정하고, 후건부 퍼지변수는 환기창열음량 증분으로 결정하여 실내온도 하나만의 계측으로 제어출력이 가능한 퍼지제어 알고리즘을 구성하였다. 퍼지변수의 범위는 기초환기실험을 통하여 결정한 후 제어주기 3분을 갖는 실제실험 시 최적 값으로 보정하였다. 전건부 퍼지변수인 제어오차와 제어오차 증분의 최적범위는 각각 목표 제어오차의 3배와 1.5배, 후건부 퍼지변수인 환기창열음량 증분의 최적범위는 최대 열림량의 30%로 나타났다. 최적화한 19개의 퍼지규칙을 적용한 퍼지제어 알고리즘을 개발하고 상대적 성능평가를 위하여 최적 게인을 부여한 PID제어와 비교하였다. 퍼지제어와 PID제어의 실내온도 제어오차는 각각 1.3$^{\circ}C$, 2.2$^{\circ}C$ 미만으로 나타났다. 퍼지제어와 비교하였다. 퍼지제어와 PID제어의 실내온도 제어오차는 각각 1.3$^{\circ}C$, 2.2$^{\circ}C$ 미만으로 나타났다. 퍼지제어는 PID제어에 비해 환기창 적산열음량, 조작회수 및 반전조작회수가 0.4배, 05배 및 0.3배로 적게 나타나 외기풍속과 실내외온도차의 변동에 유연하게 대처하며 환기창의 점진적 여닫음 조작이 가능하고, 조작에너지도 1/2로 줄일 수 있는 것으로 나타났다.

• 한국기계가공학회지
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• 제8권4호
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• pp.110-121
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• 2009

It is essential to embed product quality in the design process to win the global competition. Many components found in many products including automobiles and electronic devices are fabricated using sheet metal forming processes. Wrinkle and fracture are two types of defects frequently found in the sheet metal forming process. Reducing such defects is a hard problem as they are affected by many uncontrollable factors. Attempts to solve the problem based on traditional deterministic optimization theories are often led to failures. Furthermore, the wrinkle and fracture are conflicting defects in such a way that reducing one defect leads to increasing the other. Hence, it is a difficult task to reduce both of them at the same time. In this research, a new design method for reducing the rates of conflicting defects under uncontrollable factors is presented by using operating window and a sequential search procedure. A new SN ratio is proposed to overcome the problems of a traditional SN ratio used in the operating window technique. The method is applied to optimizing the robust design of a sheet metal forming process. To show the effectiveness of the proposed method, a comparison is made between the traditional and the proposed methods using simulation software, applied to a design of particular sheet metal forming process problem. The results show that the proposed method always gives a more robust design that is less sensitive to noises than the traditional method.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 D
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• pp.2469-2471
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• 2002

MMI 시스템은 제철 공정에서 발생되는 다양한 데이터를 조업자에게 쉽고 빠르게 전달하기 위해, real time operating system에서 동작하는 제철공정의 주된 제어 프로세스와 인터페이스 한다. 따라서 MMI 시스템은 제철 공정의 주된 제어 프로세스와 ethernet network을 통해 공유 데이터들을 통신하도록 개발되고, MMI 시스템은 M/S window operating system과 DDE(Dynamic Data Exchange) 라이브러리 환경을 기반으로 개발된다. 수 개의 MMI client PC와 1 개의 MMI server로 구성되는 MMI 시스템은 MMI client들 사이의 공유 데이터가 동기화될 수 있도록 최적 packet 양을 도출하고, 신뢰성 높은 데이터 전송을 위한 특별한 데이터 핸들링 방법을 사용한다. MMI 시스템은 GUI(Graphic User Interface)를 사용하여 조업자에게 친숙한 window 화면을 제공하므로, MMI 시스템의 화면 수정, 첨가 및 삭제가 비용 부담없이 용이하게 진행되므로, 기존 제철 공정에서 사용하던 OCP(Operating Control Panel)들이 MMI 시스템으로 대체되고 있다.

• 디지털콘텐츠학회 논문지
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• 제18권7호
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• pp.1393-1401
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• 2017

리눅스 운영체제는 데스크톱이나 서버뿐만 아니라 모바일 기기, 자동차, 임베디드 기기 등 다양한 분야로 영역을 넓혀가고 있고, 자유롭게 사용가능한 공개 소프트웨어라는 특징으로 인해 운영체제 부문에서 대부분 선두권을 차지하고 있다. 그러나 데스크톱 분야는 마이크로소프사의 윈도우가 장악하고 있고, 애플사의 Mac OS도 매니아층을 중심으로 점유율을 높이고 있으나 리눅스의 성장세는 답보 상태이다. 이러한 열세를 만회할 수 있는 중요한 요소로는 X 윈도 시스템을 손꼽을 수 있다. 아직까지 대부분의 리눅스 배포판이 전통적인 구조의 X.org 서버를 X 윈도 시스템으로 사용하는데, 무겁고 처리 속도도 느린 단점이 있다. 이를 대체하기 위해 Wayland라는 새로운 구조의 X 윈도 시스템이 등장하였다. Wayland는 임베디드나 모바일 기기에서 적합할 만큼 작고 가벼워서 데스크톱 분야뿐만 아니라 사물인터넷 관련 기기에도 탑재할 수 있다. Wayland의 등장과 더불어 시작된 X 윈도의 변화는 리눅스 대중화에 박차를 가할 것으로 판단된다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2016년도 춘계 학술논문 발표대회
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• pp.255-256
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• 2016

In order to overcome the limitation of conventional cleaning method by workers, variety attempts to develop a window cleaning apparatus has been tried. However, the existing cleaning devices were lack of consideration for avoiding projection parts of the window such as frames or profiles. In this study, operating mechanism of cleaning tool for avoiding the projections parts using a two-axis robot is proposed. Proposed mechanism is that a wiper are reposed in a relatively stationary in the vicinity of the projection and avoided the projection in this state. It is expected that the mechanism is the base of driving cleaning tool part in the new window cleaning apparatus.

• 정보학연구
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• 제8권3호
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• pp.143-158
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• 2005

The purpose of the paper is to analyze situations and its prospect of Single Window System for custom's one-stop service in Japan and to suggest effective application was to improve of in Korea's Customs systems. In response to the growing demand for lower trading costs and shorter and more predictable lead times with the advancement of the international trade supply chain, the Single Window System for import/export and port-related procedures was launched on 23 July 2003 in Japan. The concept of the Single Window System is to establish a comprehensive computer interface system that enables users to complete all import/export and port-related procedures required under different laws and regulations in a single input and single transmission. To realize the concept, the data elements and submission times of the various systems were harmonized, and manual procedures, such as quarantine and immigration, were computerized. Then, all the necessary systems, such as NACCS, Port EDI System, and Crew Landing Permit Support System, were interconnected as a Single Window System. Close cooperation among other governmental organizations and the private sector was a key factor in the successful development and smooth utilization of the System so that it fully met all parties' needs. It is anticipated that operating costs will be greatly reduced and trade facilitation will be enhanced as a result of the simplification of procedures. Korea Customs advocates the Single Window System as a best practice at ASEAN and WCO to contribute to the development of regional and international capacity building.

• 농업과학연구
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• 제44권4호
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• pp.595-603
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• 2017

Crop growth and production cost are greatly influenced by management of environmental factors such as ambient temperature, humidity, and $CO_2$, especially in protected horticulture. Opening and closing of greenhouses is the most important operation for control of these ambient environmental factors, and precise and stable operation requires high performance window motors. In this study, a 400 W precise window motor was constructed, and its performance was evaluated for plastic and glass greenhouses. First, the motor was designed and fabricated by benchmarking of an advanced foreign product. Then, the performance was evaluated through vibration, PCB (Process Control Block), and load tests. Vibration tests resulted in averaged vibration displacement and velocity of the developed motor of 0.002 mm and 0.2267m/s, which were statistically significantly different from those of the target motor. Average vibration acceleration ($0.26m/s^2$) of the developed motor was also significantly different from that ($0.51m/s^2$) of the target motor. PCB tests showed 2 - 4 mm deviation from the target values, and confirmed the operating status and precision of the control. Load tests with a 300 kg load also showed acceptable operating status and durability. Current values were $1.31{\pm}0.06A$ and RPMs were in the range of 2.9 - 3.0. Considering the above results, the developed window motor would be competitive to the target foreign product.