• 한국군사과학기술학회지
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• 제11권3호
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• pp.89-98
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• 2008

The vetronics is necessarily required for enhancement of the operational capability and optimization of the system architecture. In this paper, we presents the realtime control methods for the vetronics of the fighting vehicles. We proposed the data distribution based on standard bus and computer resource for realtime and integrated control of the system. Embedded computers are designed considering extensibility and reliability of the system. The integrated display improves the operator's capability. We applied the network centric battle management and digital power control with intelligent switching elements to increase cooperated combat efficiency and reliability. To show the feasibility of the presented design schemes, the vetronics has been implemented and applied to a real fighting vehicle.

• 정보처리학회논문지C
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• 제10C권3호
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• pp.345-354
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• 2003

멀티캐스트 방식은 네트워크 자원을 효율적으로 사용할 수 있다는 장점을 갖는 반면 신뢰성을 기본적으로 제공하지 않기 때문에 이를 해결하기 위한 다양한 연구가 진행되어 왔다. 하지만 기존 연구는 패킷기반의 신뢰성 보장에 국한되어 있기 때문에 멀티미디어 데이터를 전송하는 경우에는 프레임간의 의존성과 적절한 시간에 수신측에서 재생되어야하는 제약을 해결하지 못한다. 따라서 멀티미디어의 특성을 고려한 신뢰성과 확장성을 보장하는 연구가 필요하다. 본 논문에서는 이와 같은 문제를 해결하기 위해서 신뢰성을 지원하는 트리기반 멀티캐스트 상에서 H.263의 특성을 인식하여 확장성을 보장하는 선행에러복구(PER)를 제안한다. 제안하는 방식은 수신노드의 상태를 고려하여 제어패킷의 발생을 줄이고 언더플로우 상태의 수신노드의 스트림 버퍼의 빠른 복구를 가능하게 한다. 성능분석 결과, 제안하는 방식은 멀티미디어 데이터에 적용하는 경우 확장성에서 기존 연구보다 우수함을 보였다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2010년도 춘계학술대회 논문집
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• pp.401-402
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• 2010

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.188-194
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• 2011

The purpose of this paper is to explain the implementation method in order to enhance stability and reliability of embedded system. In this research, Texas Instrument (TI)'s TMS570 MCU(Micro Controller Unit) is used to satisfy the standard of stability that is IEC 61508. IEC 61508 suggest SIL(Safety Integrity Level) from 1 to 4 and TMS570 is satisfied SIL3. Also, TMS570 can provide several stability functions can be used in realtime system. To use such functions, this paper suggest the solution about the defect that can be used in realtime system. In basic way TMR(Triple Modular Redundancy) suggested in addition to explain about the way to improve safety and reliability. Also this paper will suggest the method that reinforce the stability of calculation by using multiplex voter and memory.

• 디지털산업정보학회논문지
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• 제5권4호
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• pp.39-49
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• 2009

Nowadays, according to rapid development of computing environments, information processing and analysis system are very interesting research area. As a viewpoint of data preparation-processing-analysis in knowledge technology, the goal of automated information system is to satisfy high reliability and confidence and to minimize of human-administrator intervention. In addition, we expect the system which can deal with problem and abnormal error effectively as a fault detection and fault tolerance. In this paper, we design a monitoring system as follows. A productive monitoring information from various systems has unstructured forms and characteristics and crawls informative data by conditions and gathering rules. For representing of monitering information which requested by administrator, running-status can be able to check dynamically and systematic like connection/closed status in real-time. Our proposed system can easily correct and processing for monitoring information from various type of server and support to make objective judgement and analysis of administrator under operative target of information system. We implement semi-realtime monitering system using AJAX technology for dynamic browsing of web information and information processing using XML and XPATH. We apply our system to SMS server for checking running status and the system shows that has high utility and reliability.

• 전기학회논문지
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• 제59권10호
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• pp.1741-1747
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• 2010

The development of overload management systems for distribution transformers offers new opportunities for improving the reliability of distribution systems. It allows network planners to optimize the system resource utilization and investment cost. Such an improvement in the flexibility of the distribution network is only possible if the operator has more accurate knowledge of the realtime conditions of distribution transformers. In this paper, we present an improved overload decision system for distribution transformers using realtime monitoring data. Our study can be categorized into two parts: (a) improvement in the criteria for judging the overload conditions of distribution transformers and (b) development of an overload evaluation system using realtime monitoring data. In order to determine the overload criteria, overload experiments are performed on sample transformers; the results of these experiments are used to define the relationship between the transformer overload and the increase in the top-oil temperature. To verify the accuracy of the experimental results, field tests are performed using specially manufactured transformers, the loads and top-oil temperatures of which can be measured. For arriving at online overload decisions, we propose methods whereby the measured load curve can be converted into an overload characteristic curve and the overload time can be calculated for any load condition. The developed system is able to evaluate the overload for individual distribution transformers and calculate the losses using realtime monitoring data.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1996년도 추계학술대회 논문집
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• pp.255-259
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• 1996

This paper describes a system for measurement and control of a gas flow. In order to measure the flux of gas and control a vavle according to flux, this system was developed. This system is implemented on the personal computer and its environment is developed tool called TMS. This system includes a main program and Tele-Metering Unit for transmitting correcting flow value based on temperature and pressure in flow computer and AD converter for transmitting instantaneous flow rate, temperature and pressure as interface part of personal computer. This system was made by Visual C++ program. Using this system, inspected data for the recognition of transmitting flow value are generated on the screen, file and printer. The activity, reliability of this system was verified on Daegu-Citygas that aids the system for the acquisition of inspected data by realtime application.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2006년도 추계학술대회 논문집
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• pp.947-953
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• 2006

ATC on-board equipment require realtime embedded software with high level of safety and reliability. To satisfy these requirements, many techniques are applied to the development of software during the lifecycle. In case of software modeling, object-oriented methodology is widening its niche replacing traditional structured methodology and modeling in UML using a CASE tool is a growing trend. In this paper, we modeled ATC on-board software in UML using Rhapsody, which is a modeling tool for realtime embedded software. We modeled the behavior of ATC on-board equipment based on state machine diagram and validated the model using the animation feature provided in the tool. According to our study, the CASE tool based on UML showed high level of applicability in modeling and verifying the software with complex behavioral characteristics.

• 한국항행학회논문지
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• 제9권1호
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• pp.61-69
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• 2005

인터넷 전송계층 프로토콜에는 TCP와 UDP가 있다. TCP는 연결형 프로토콜로서 에러 제어 및 흐름 제어를 제공하여 신뢰성있는 데이터 전송은 보장하지만 그에 따른 전송 지연이 발생한다. 반면에 UDP는 비연결형 프로토콜로서 에러 제어 및 흐름 제어를 수행하지 않으므로 데이터 전송에 있어 지연이 발생되지 않아 실시간 전송은 보장하나 신뢰성있는 데이터 전송을 보장할 수 없다. 따라서 현재의 인터넷 전송계층 프로토콜에서는 실시간 전송기능을 제공하는 동시에 높은 수준의 신뢰성을 보장하여야 하는 데이터의 전송에 적당한 프로토콜이 없다. 본 논문에서는 리눅스(Linux) 커널(Kernel)의 TCP의 에러제어 및 흐름제어를 수정하여 실시간 전송기능을 제공하는 동시에 높은 수준의 신뢰성을 보장하는 새로운 프로토콜을 설계, 구현하였다. 본 연구에서 설계된 실시간 전송기능을 지원하는 TCP 프로토콜은 기존의 TCP에 새로운 옵션을 추가함으로써, 기존 TCP와의 호환성을 유지할 수 있도록 하였다.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 2006년도 추계학술대회
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• pp.312-315
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• 2006

Overlay Multicast is a promising approach to overcome the implementation problem of IP multicast. Real time services like internet broadcasting are provided by overlay multicast technology due to the complex nature of IP multicast and the high cost to support multicast function. Since multicast members can dynamically join or leave their multicast group, it is necessary to keep a reliable overlay multicast tree to support real time service without delay. In this paper, we consider path level reliability that connects each member node. The problem is formulated as a binary integer programming which maximizes the reliability of multicast tree. Tabu search based algorithm is presented to solve the NP-hard problem.