• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2008년도 한국컴퓨터종합학술대회논문집 Vol.35 No.1 (D)
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• pp.291-296
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• 2008

Wireless network technologies are becoming more widely used in industrial environment. The industrial communication system requires a real-time delivery of messages. The sensors periodically senses the physical environment and wants to deliver the data in real-time to the sink. This paper proposes a real-time protocol for periodic messages on wireless sensor and actor networks to be used in industrial communications. The proposed protocol delivers the data message using the shortest path from the source and the nearest actor. The protocol considers the energy consumption by reducing the number of broadcast messages during flooding. We have evaluated the performance of the proposed protocol using QualNet simulator. The simulation results show that the data messages have been delivered in real-time and the number of broadcast messages is reduced from 90% to 35% compared the existing protocols.

• 한국컴퓨터정보학회논문지
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• 제15권9호
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• pp.19-24
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• 2010

우리나라 자동차의 수는 1990년부터 계속 증가하고 있다. 계속되는 자동차 수의 증가로 인해 휴일, 출퇴근 시간에 교통이 혼잡 또는 마비되는 문제가 발생한다. 하지만 기존의 신호등 체계는 통계적인 수치에 의해 결정되기 때문에 항상 일정하지 않은 차량의 수를 제어하기에는 한계가 있다. 따라서 본 논문에서는 실시간으로 변하는 차량의 수와 점유시간에 따라 퍼지 제어 기법을 이용하여 신호를 제어하는 방법을 제안한다. 제안된 교통 신호 제어 방법은 교차로에 대기하는 차량의 수와 점유 시간을 퍼지 제어 기법에 적용하여 차량의 진행 신호에 대한 우선순위를 부여한다. 가장 높은 우선순위를 가지는 현시에 대해 진행 신호를 부여하고 나머지는 대기하게 된다. 그리고 진행 신호의 시간을 교차로에 대기하는 모든 차량의 수와 차량의 비율, 진행 신호를 부여 받은 차량의 수를 이용하여 계산한다. 본 논문에서는 제안된 퍼지 신호 제어 기법과 정적인 신호 제어 기법에 대해 시뮬레이션을 통해 실험한 결과. 차량 혼잡도와 상관없이 제안된 차량 신호 제어 기법이 동일한 시간에 더 많은 차량이 원활하게 소통되는 것을 확인하였다.

• The Journal of the Acoustical Society of Korea
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• 제20권4E호
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• pp.52-60
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• 2001

This paper describes real time implementation of subband sound localization system on a floating-point DSP TI TMS320C31. The system determines two dimensional location of an active speaker in a closed room environment with real noise presents. The system consists of an two microphone array connected to TI DSP hosted by PC. The implemented sound localization algorithm is Subband CPSP which is an improved version of traditional CPSP (Cross-Power Spectrum Phase) method. The algorithm first split the input speech signal into arbitrary number of subband using subband filter banks and calculate the CPSP in each subband. It then averages out the CPSP results on each subband and compute a source location estimate. The proposed algorithm has an advantage over CPSP such that it minimize the overall estimation error in source location by limiting the specific band dominant noise to that subband. As a result, it makes possible to set up a robust real time sound localization system. For real time simulation, the input speech is captured using two microphone and digitized by the DSP at sampling rate 8192 hz, 16 bit/sample. The source location is then estimated at once per second to satisfy real-time computational constraints. The performance of the proposed system is confirmed by several real time simulation of the speech at a distance of 1m, 2m, 3m with various speech source locations and it shows over 5% accuracy improvement for the source location estimation.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 ITC-CSCC -2
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• pp.1256-1259
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• 2002

In this paper, we have proposed license plate recognition system for multi-national vehicle license plate using geometric features along with hybrid and seven segment pattern vectors. In the proposed system, we suggested to find horizontal and vertical relation after going through preparation process with inputted real-time license plate image of Korea and Japan, and then to classify license plate with using characteristic and geometric information of license plates. It classifies the extracted license plate images into letters and numbers, such as local name, local number, classification character and license consecutive numbers, and recognize license plate of Korea and Japan by applying hybrid and seven segments pattern vectors to classified letter and number region. License plate extraction step of the proposed system uses width and length information along with relative rate of Korean and Japanese license plate. Moreover, it exactly segmentation by letters with using each letter and number position information within license plate region, and recognizes Korean and Japanese license plates by applying hybrid and seven segment pattern vectors, containing characteristics related to letter size and movement within segmented letter area. As the result of testing the proposed system in real experiment, it recognized regardless of external lighting conditions as well as classifying license plates by nations, Korea and Japan. We have developed a system, recognizing regardless of inputted structural character of vehicle licenses and external environment.

• 한국산학기술학회논문지
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• 제13권2호
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• pp.795-800
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• 2012

최근 들어 유, 무선 네트워크를 통한 통신이 비약적으로 발전함에 따라 다양한 서비스가 통신망을 통하여 일상적으로 이루어지고 있다. 이에 따라 데이터 및 개인 정보를 보호할 수 있는 기술이 필수적으로 요구되어 지고 있으며, 이러한 정보보호 문제를 해결할 수 있는 보안 기술에 대한 연구가 활발하게 진행되고 있다. 본 논문에서는 다양한 암호 알고리즘들 중 타원곡선 암호의 키 선택 범위를 확장하기 위하여 실수체 기반 타원곡선 알고리즘의 연산항에 대한 연구를 수행하였다. 실험 결과, 실수체를 사용한 타원곡선 암호는 기존의 정수를 이용한 타원곡선 암호보다 다양한 키를 선택할 수 있어 보다 안전한 암호 시스템을 구현할 수 있음을 알 수 있었다.

• Smart Structures and Systems
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• 제14권6호
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• pp.1005-1030
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• 2014

The need for assessing dynamic response of typical industrial piping systems subjected to seismic loading motivated the authors to apply model reduction techniques to experimental dynamic substructuring. Initially, a better insight into the dynamic response of the emulated system was provided by means of the principal component analysis. The clear understanding of reduction basis requirements paved the way for the implementation of a number of model reduction techniques aimed at extending the applicability range of the hybrid testing technique beyond its traditional scope. Therefore, several hybrid simulations were performed on a typical full-scale industrial piping system endowed with a number of critical components, like elbows, Tee joints and bolted flange joints, ranging from operational to collapse limit states. Then, the favourable performance of the L-Stable Real-Time compatible time integrator and an effective delay compensation method were also checked throughout the testing campaign. Finally, several aspects of the piping performance were commented and conclusions drawn.

• 대한조선학회논문집
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• 제47권6호
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• pp.836-842
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• 2010

Safety system including location monitoring system for blasting workers was studied. Positioning performance of the location monitoring system was highly dependent on communication protocol and the number of access points in the blasting cell. RTLS(Real Time Location System) is an important technology to develop the location information of workers and variously used to enhance workers safety. Location monitoring system with Cell-ID and RSSI wireless communication technology was verified to have a proper positioning performance for the steel block application.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2003년도 추계종합학술대회
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• pp.986-989
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• 2003

철강공정 중에서 고로에서 용융된 쇳물은 연주공정을 거쳐 슬라브(slab) 재질로 변한 후 다음 공정인 열연공정으로 이동하게 된다. 본 논문은 슬라브 재질의 단면에 마킹된 소재관리번호를 슬라브가 열연공정으로 이동하기 전에 철강공정 상에서 실시간으로 인식하기 위한 인식시스템 개발에 관한 연구다. 이를 위해 획득한 슬라브의 단면 영상에 대해 전처리 필터를 적용하여 노이즈를 제거시킨 그레이레벨 영상에 대해 대략적인 번호영역을 추출한 후, 개별 번호영역을 추출하여 최종으로 소재의 관리번호를 추출하는 방법을 사용한다. 그리고 슬라브의 소재 관리번호 추출을 위해 KL-변환 (Karhunen-Loeve transform) 알고리즘을 사용한다. 개발된 슬라브번호 인식 시스템을 사용하여 실제로 공정 상에서 획득한 슬라브 단면 영상데이터에 대해 적응해본 결과 약 94%의 인식률을 가졌다.

• 산업경영시스템학회지
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• 제42권1호
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• pp.55-63
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• 2019

This paper develops an algorithm to determine the batch size of the batch process in real time for improving production and efficient control of production system with multiple processes and batch processes. It is so important to find the batch size of the batch process, because the variability arising from the batch process in the production system affects the capacity of the production. Specifically, batch size could change system efficiency such as throughput, WIP (Work In Process) in production system, batch formation time and so on. In order to improve the system variability and productivity, real time batch size determined by considering the preparation time and batch formation time according to the number of operation of the batch process. The purpose of the study is to control the WIP by applying CONWIP production system method in the production line and implements an algorithm for a real time batch size decision in a batch process that requires long work preparation time and affects system efficiency. In order to verify the efficiency of the developed algorithm that determine the batch size in a real time, an existed production system with fixed the batch size will be implemented first and determines that batch size in real time considering WIP in queue and average lead time in the current system. To comparing the efficiency of a system with a fixed batch size and a system that determines a batch size in real time, the results are analyzed using three evaluation indexes of lead time, throughput, and average WIP of the queue.

• Journal of Advanced Marine Engineering and Technology
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• 제22권6호
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• pp.901-907
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• 1998

This paper presents a real-time control technique for the development of a ship main engine remote control system, In general several tasks are executed by the event-driven method in real-time system. However when some tasks have time delay components it is difficult to achieve good real-time performance. To cope with this problem a number of timers in most conventional system have been used. In this paper we introduce a real-time control methodology of dealing effectively with tasks including time delay components using one hardware timer. And also a speed control method of main engine which includes critical revolution range a crash astern and a emergency ahead function a switching method of remote control position and a flickering method for the indication of multi-stage alarm are discussed. As long as functions and method are imple-mented as forms of tasks the development of main engine remote control systems can be easy for different types of engines.