• 한국컴퓨터정보학회논문지
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• 제25권11호
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• pp.115-122
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• 2020

본 논문에서는 실시간 공정능력관리 기반의 MES(Manufacturing Execution System) 시스템과 해당 시스템을 활용한 제조 업무 수행 절차에 대해서 제안한다. 현 MES 시스템은 제조 현장을 쉽게 인지할 수 있는 KPI(Key Performance Indicator) 리포트는 제시하지만, 실질적 제조 현장의 KPI 향상을 위한 개선 방안은 도출하지 못하고 있다. 즉, 불량률 증가, 수율 감소, 생산 리드 타임(Lead-Time) 증가의 궁극적 원인을 발췌하여 개선 방안을 도출하고, 이를 제조 현장에 적용하는 부분에는 어려움이 있다. 본 논문에서 제안하는 실시간 공정능력관리 기반의 MES 시스템은 공정능력지수를 결정하는 설비 주요 인자의 산포도를 실시간으로 관리하여, 기존 MES 시스템의 한계점을 극복한 제조 운영 관리시스템 구축이 목적이다. 그리고, 실시간 대용량 데이터 처리를 위한 속도개선 방안을 제시하여, 해당 시스템이 잘 운영될 수 있도록 적용하려고 한다.

• 대한산업공학회지
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• 제33권2호
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• pp.221-226
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• 2007

This paper suggests a valuation framework of investment project using the concept of real options. We show the valuation process of real assets using the risk-neutral pricing. Especially, we focus on the investment lag. Real assets have investment lag in general. The decision time and the payment time are not identical. So the investment lag should be considered when valuing real assets for reality. We provide the valuation process for real assets, including R&D project. The results of this paper can be used for the real assets valuation and strategic decision analysis.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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• pp.46-51
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• 2001

For Fast Real-time Recognition of Nonlinear Error Data, a new Neural Network algorithm which recognized the map in real time is proposed. The proposed neural network technique is the real time computation method through the inter-node diffusion, In the network, a node corresponds to a state in the quantized input space. Each node is composed of a processing unit and fixed weights from its neighbor nodes as well as its input terminal. The most reliable algorithm derived for real time recognition of map, is a dynamic programming based algorithm based on sequence matching techniques that would process the data as it arrives and could therefore provide continuously updated neighbor information estimates. Through several simulation experiments, real time reconstruction of the nonlinear map information is processed,

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집
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• pp.46-51
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• 2001

For Fast Real-time Recognition of Nonlinear Error Data, a new Neural Network algorithm which recognized the map in real time is proposed. The proposed neural network technique is the real time computation method through the inter-node diffusion. In the network, a node corresponds to a state in the quantized input space. Each node is composed of a processing unit and fixed weights from its neighbor nodes as well as its input terminal. The most reliable algorithm derived for real time recognition of map, is a dynamic programming based algorithm based on sequence matching techniques that would process the data as it arrives and could therefore provide continuously updated neighbor information estimates. Through several simulation experiments, real time reconstruction of the nonlinear map information is processed.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 1995년도 특별강연 및 추계학술발표 개요집
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• pp.3-20
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• 1995

Development of Real-Time Quality Evaluation of Friction Welding by Acousitc Emission : Report 1 ABSTRACT : According as the friction welding has been increasingly applied in manufacturing various machine components because of its significant economic and technical advantages, one of the important concerns is the reliable quality monitoring method for a good weld quality with both joint strength and toughness in the process of its production. However no reliable nondestructive test method is available at present to determine the weld quality particularly in process of production. So this paper presents an experimental examination and quantitative analysis for the real-time evaluation of friction weld quality by acoustic emission, as a new approach which attempts finally to develop an on-line quality monitoring system design for friction welds using AE techniques. As one of the important results, it was confirmed, through this study, that AE techniques can be reliably applied to evaluating the friction weld qualify with 100% joint strength, as the cumulative AE counts occurring during welding period were quantitatively correlated with reliability at 95% confidence level to the joint strength of welds. Real-Time Evaluation of Automatic Production Quality Control for Friction Welding Machine : Report 2 Abstract : Both in-process quality control and high reliability of the weld is one of the major concerns in applying friction welding to the economical and qualified mass-production. No reliable nondestructive monitoring method is available at present to determine the real-time evaluation of automatic production quality control for friction welding machine. This paper, so that, presents the experimental examinations and statistical quantitative analysis of the correlation between the initial cumulative counts of acoustic emission(AE) occurring during plastic deformation period of the welding and the tensile strength of the welded joints as well as the various welding variables, as a new approach which attempts finally to develop an on-line (or real-time) quality monitoring system and a program for the process of real-time friction welding quality evaluation by initial AE cumulative counts. As one of the important results, it was well confirmed that the initial AE cumulative counts were quantitatively and cubically correlated with reliability of 95% confidence level to the joint strength of the welds, bar-to-bar (SCM4 to SUM31, SCM4 to SUM24L) and that an AE technique using initial AE counts can be reliably applied to real-time strength evaluation of the welded joints, and that such a program of the system was well developed resulting in practical possibility of real-time quality control more than 100% joint efficiency showing good weld with no micro-structural defects.

• 한국정보처리학회논문지
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• 제7권6호
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• pp.1753-1765
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• 2000

As the areas of computer application are expanded, real-time application environments that must process as many transactions as possible within their deadlines, such as a stock transaction systems, ATM switching systems etc, have been increased recently. The reason why the conventional database systems can't process soft real-time applications is the lack of prediction and poor performance on processing transaction's deadline. If transactions want to access data stored at the secondary storage, they can not satisfy requirements of real-time applications because of the disk delay time. This paper designs a main-memory database prototype systems to be suitable to real-time applications and then this system can produce rapid results without disk i/o as all of the information are loaded in main memory database. In thesis proposed the improved techniques with respect to logging, checkpointing, and recovering in our environment. In order to improve the performance of the system, a) the frequency of log analysis and redo processing is reduced by the proposed redo technique at system failure, b) database consistency is maintained by improved fuzzy checkpointing. The performance model is proposed which consists of two parts. The first part evaluates log processing time for recovery and compares with other research activities. The second part examines checkpointing behavior.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.350-353
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• 2004

The increasing use of Ethernet-TCP/IP network in industry has led to the growing interest in its reliability in real-time applications such as automated manufacturing systems and process control systems. However, stochastic behavior of its medium access scheme makes it inadequate for time-critical applications. In order to guarantee hard real-time communication service in Ethernet-TCP/IP network, we proposed an algorithm running over TCP/IP protocol stack without modification of protocols. In this paper, we consider communication services guaranteeing deadlines of periodic real-time messages over MAC protocols that have unbounded medium access time. We propose a centralized token scheduling scheme for multiple access networks. The token is used to allow a station to transmit its message during the time amount that is appended to the token. The real-time performance of the proposed algorithm has been described.

• 한국게임학회 논문지
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• 제5권2호
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• pp.3-9
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• 2005

인터렉티브 리얼 타임 3D(Interactive real-time 3D)는 유저가 가상의 3차원 세계를 탐색하고 또한 몰입하는 폼의 컨텐츠를 경험할 수 있게 해준다. 다른 매체와는 다르게, 인터렉티브 리얼 타임 3D의 사용자(user)는, 디지털 3D의 구조에서의 작용과 반작용이 즉시 일어나는 "실시간"에서 진행되는 프로세스에서 능동적인 역할을 수행한다.

• Journal of Welding and Joining
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• 제33권4호
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• pp.24-29
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• 2015

The current waveform was analysed to monitor the weld quality in real time process. The acquired current waveform was discretely analysed for the top and bottom limits of peaks as well as the pulse frequency measurement. Fast Fourier Transform was implemented in the program to monitor the pulse frequency in real time. The developed algorithm or program was tested for the validation purpose. The cross-section of weld profile was compared to the current waveform profile to correlate the monitored signal and the actual parts. Pulse frequency was also used as auxiliary tool for the quality monitoring. Based on the results, it was possible to evaluate the quality of welding by measure the current waveform profile and frequency measurement.

• 한국통신학회논문지
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• 제22권6호
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• pp.1365-1376
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• 1997

In this paper, we designed real time mechanism control language and proposed execution time analysis technique. It was impossible to handle real-time mechanism control programs like programmable controller, numerical controller, distributed control system and robot controller with general purpose programming languages and operating systems because they have to process electric signals generated by thousands of sensors at the same at the same time and in real time. So we made it possible to predict plausibility of time constraint constructs of tiem constraint construct of a real time application program at compilation time by adding time constraint constructs and mechanism synchronization structure to conditional statement and iteration statement of a programming language and developing execution time analysis technique.