• 연구논문집
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• 통권22호
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• pp.21-26
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• 1992

Dynamic analysis is important in structural design of SCARA or articulated type industrial robots and is' usually done to main three axes. In this paper, robot arm dynamics was analyzed using FBD(free body diagram). Though the proposed scheme becomes complex as DOF(degree of freedom)increases, it allows to see types and directions of forces and moments acting on the body. Therefore, the strength analysis of robot arm can be done relatively easy in a case of either closed or open loop chain. This method can be used for obtaining dynamic simulation at off-line programming system and calculating required torques at joints at on-line system.

• 한국안광학회지
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• 제13권1호
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• pp.31-35
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• 2008

목적: 본 논문은 CCTV 카메라용 렌즈 설계를 triplet형으로 광학 설계를 하였다. 방법: 초점거리를 56 mm, 유효경을 20 mm 그리고 화각을 $5^{\circ}$로 한 망원 렌즈 형태이고, 설계하고자 하는 카메라의 CCD array detector의 크기를 2/3인치로 하였다. 결과: 광학계의 성능은 ray-fan과 spot diagram 그리고 회절 광학적인 MTF를 계산하여 평가하였고, 파장은 Fraunhofer C, d 및 F-line에 대해 achromat 되었으며 MTF 값도 tangential과 sagittal MTF 모두 50 line pairs/mm의 공간 주파수에 70% 정도가 나왔다. 결론: triplet형으로 비교적 저가 보급형 감시용 목적 CCTV 카메라를 설계하였고 충분히 실용적이라 생각된다.

• 인터넷정보학회논문지
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• 제18권4호
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• pp.79-87
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• 2017

Company A, an embedded system manufacturer, provides its products to Company P which is the parent company of Company A. Both companies learned that they needed to find over 4,000 bugs before market release in order to meet the acceptable quality level. Traditionally, they had utilized time-series line graphs as their common performance measurement tool. These graphs compared accumulated numbers of bugs fixed with accumulated numbers of bugs found. Engineers in Company A had been under pressure to improve the process capacity because the line for bugs fixed was always below than the line for bugs found. By using a newly designed Bipolar diagram, engineers in Company A analyzed the process performance. And they were in a position to be more flexible for internal or inter-companies meeting. Authors explain an empirical study of a graphical and practical performance measurement tools relating to mainly the Bipolar diagram. As a result, the Bipolar diagram provides workload monitoring and performance measurement functions in a given timeframe by using the concepts of Optimum Process Line (or band) and Fair Process Capacity Zone.

• 대한산업공학회지
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• 제14권2호
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• pp.71-80
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• 1988

The primary purpose of this study is to develop an automation tool capable of converting the specification of structured analysis into that of structured design. Structured Analysis and Structured Design Language (SASDL) is a computer-aided description language based on ERA model and particulariged by ISLDM/SEM. The automation tool utilizes the specifications of data flow diagram described in SASDL to produce their corresponding SASDL specification of structure chart. The main idea behind the automatic conversion process is to categorize the bubbles in data flow diagram and to determine the positions of the bubbles in structure chart according to their categories and the relative locations in data flow diagram. To make the problem into manageable size, the whole system is broken down into separate parts called activity units. A great deal of manual jobs, such as checking processes leveling, checking data derivation of processes, deriving structure chart from data flow diagram, checking any inconsistency between data flow diagram and structure chart and so forth, can be automated by using SASDL and conversion tool. The specification of structure chart derived by conversion tool may be used in an initial step of design to be refined by SASDL users.

• 한국융합학회논문지
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• 제13권3호
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• pp.1-9
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• 2022

UML(Unified Modeling Language) 클래스 다이어그램은 시스템의 정적인 측면을 표현하며 분석 및 설계부터 문서화, 테스팅까지 사용된다. 클래스 다이어그램을 이용한 모델링이 소프트웨어 개발에 있어 필수적이지만, 경험이 많지 않은 모델러에게 쉽지 않은 작업이다. 도메인 카테고리별로 분류된 클래스 다이어그램 데이터 세트가 제공된다면, 모델링 작업의 생산성을 높일 수 있을 것이다. 본 논문은 클래스 다이어그램 이미지 데이터를 구축하기 위한 자동 분류 기술을 제공한다. 추가 정보 없이 단지 UML 클래스 다이어그램 이미지를 식별하고 도메인 카테고리에 따라 자동 분류한다. 먼저, 웹상에서 수집된 이미지들이 UML 클래스 다이어그램 이미지인지 여부를 판단한다. 그리고, 식별된 클래스 다이어그램 이미지에서 클래스 이름을 추출하여 도메인 카테고리에 따라 분류한다. 제안된 분류 모델은 정밀도, 재현율, F1점수, 정확도에서 각각 100.00%, 95.59%, 97.74%, 97.77%를 달성했으며, 카테고리별 분류에 대한 정확도는 81.1%와 95.2% 사이에 분포한다. 해당 실험에 사용된 클래스 다이어그램 이미지 개수가 충분히 크지 않지만, 도출된 실험 결과는 제안된 자동 분류 방식이 고려할 만한 가치가 있음을 나타낸다.

• 한국ITS학회 논문지
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• 제21권2호
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• pp.17-32
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• 2022

본 연구에서는 개별 차량의 차두 시간(time headway) 정보를 활용하여 고속도로 환경에서의 단일 링크에 대한 교통류 모형(flow-density diagram)을 추정하는 방법에 대해 탐구한다. 차두 시간 기반 교통류 모형(empirical flow-density diagram) 연구를 위해 차량용 비전 센서가 탑재된 실험 차량에서 9개월동안 수집된 데이터의 전처리 및 GIS 기반 맵 매칭을 수행한다. 기존의 교통류 모델식을 활용한 차두 시간 기반 교통류 모형(empirical flow-density diagram)의 검증을 위해, 차량 검지기 기반의 VDS(Vehicle Detection System) 데이터(loop detection traffic data) 기반 교통류 모형과 결과 비교 및 분석을 수행한다. 차두 시간 기반 교통류 모형의 추정 오차 원인을 분석하기 위해 각 교통류 모형의 차두 시간 및 차두 거리의 확률분포와 단위시간 교통량과 차량 밀도의 표준편차를 활용하였다. 분석 결과 링크 내 제한된 샘플 차량 대수 및 수집 데이터에 대한 주행환경 편향성이 추정 오차의 주된 요인이며. 이에 따른 추정 오차 개선을 위한 방법에 대해 제안한다.

• Journal of Mechanical Science and Technology
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• 제15권5호
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• pp.544-554
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• 2001

A shop floor can be considered as an important level to develop Computer Integrated Manufacturing system (CIMs). However, a shop floor is a dynamic environment where unexpected events continuously occur, and impose changes to the planned activities. To deal with this problem, a shop floor should adopt an appropriate control system that is responsible for the coordination and control of the manufacturing physical flow and information flow. In this paper, a hybrid control system is described with a shop floor activity methodology called Multi-Layered Task Initiation Diagram (MTD). The architecture of the control model contains three levels: i.e., he shop floor controller (SFC), the intelligent agent controller (IAC) and the equipment controller (EC). The methodology behind the development of the control system is an intelligent multi-agent paradigm that enables the shop floor control system to be an independent, an autonomous, and distributed system, and to achieve an adaptability to change of the manufacturing environment.

• 품질경영학회지
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• 제42권2호
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• pp.165-177
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• 2014

Purpose: This study analyzes the strategical priority to improve eco-labelling certification system, focused on biodegradable resin. Methods: This study will come up with measures to operate the eco-Label certification system related to biodegradable products more effectively and efficiently by discovering various problems related to the system, using causal loop diagram and AHP analysis. Results: This study shows that the government should play more important role while firms could also serve their roles in the initial and stabilizing stages of the eco-labelling certification system, in order to vitalize the eco-Label certification system more effective. Conclusion: This study addresses strategic eco-labelling policies on governmental and firm's operation and providers guidance to practitioners in addressing strategic decision relating to eco-labelling certification system.

• Journal of Multimedia Information System
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• 제3권4호
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• pp.161-168
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• 2016

In this paper, a power flow simulator, which visualizes power flow and system configuration, is proposed and implemented. Generally, it is necessary to prepare a text file with power-system descriptions, which is one of the barriers for power-flow simulations. The proposed simulator has a function of automatic generations of IEEE common data format files from user-drawn power-system diagrams. Therefore, it is possible for users to carry out simulations only by drawing power system on display. In addition, the proposed simulator also has a function that power-system diagram is illustrated automatically from an IEEE common data format file. By using this function, it is possible to visualize amounts and directions of power flows on the bus-system diagram, which helps users to comprehend network dynamics intuitively. Because the proposed simulator allows including renewable-resource generators in power systems, it is useful to evaluate the power distribution system. It is shown in this paper that the proposed simulator can make IEEE common data format files correctly and illustrate intuitive power flow.

• 한국자동차공학회논문집
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• 제3권6호
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• pp.212-223
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• 1995

To improve the efficiency of a power transmission system with slip elements, power split/circulation system is applied. The performance of a power split/circulation system varies widely by the change of the followings; the layout of system, the type and gear ratio of planetary gear, the performance of slip element, etc. Therefore, when one designs such a power transmission system or when one determines the economic/power mode of system, a certain performance prediction method is needed. In this study, the internal power flow pattern of a power split/circulation system is theoretically analyzed on several transmission systems. And an effective performance prediction method(so called performance locus diagram) is presented. By this method, the effects of design factors can be easily understood and the qualitative performances of system can be clearly evaluated.