• Journal of the Institute of Electronics Engineers of Korea CI
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• v.45 no.6
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• pp.52-59
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• 2008

Most pier performance analysis results for ad-hoc routing protocols have been based upon the model which each node in the network moves independently without restriction. In most real environments, however, it is very common for a group or multiple groups to move under the direction of group leader or group leaders instead of each node's independent movement. This paper presents the performance analysis of routing protocols for mobile ad-hoc network under group mobility environment. The comparative simulations have been made between a table-driven protocol, DSDV, and two on-demand protocols, AODV and DSR, under a group mobility model, RPGM, which is suitable for the practical applications such as military tactical operation. Multiple group movements are also included. The results show that the protocol performances for single group movement are very similar to node independent movement case. However some differences have been observed by varying pause time and connectivity.

• Proceedings of the KIEE Conference
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• 1998.07e
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• pp.1779-1781
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• 1998

We are going to design the Square Pulse Generator use of PCPS (Photo-Conductive Power Switch) for Blumlein lain. The circeuit is made of LC device and it is simulated by Schematics Evaluation Version 8.0 of MicroSim. After charged by DC voltage 15[kV]. When the switch is ON, Square pulse is generated after pause time 1.7857[${\mu}s$]. The square pulse is maximum peak voltage 13.987[kV], pulsed width 3.4017[${\mu}s$], rising time 0.7474[${\mu}s$], falling time 1.1718[${\mu}s$].

• Proceedings of the Korean Information Science Society Conference
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• 2002.10e
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• pp.343-345
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• 2002

본 논문에서 구현한 MPEG-4 미디어 재생기는 네트워크를 통하여 스트리밍 서버에 메시지를 전송하고, 스트리밍 서버로부터 전송된 미디어 스트림을 처리하여 사용자의 화면에 보여주는 역할을 수행한다. 미디어 재생기는 서버에게 VCR(Play, Pause, Stop, Jump)이벤트를 전송하며, 리눅스 운영체제에서 동작한다. 본 논문에서 제안하는 미디어 재생기는 VCR 연산을 위한 RTSP(Real Time Streaming Protocol)를 지원하며 데이터의 실시간 전송을 위하여 RTP(Real-time Transport Protocol)／RTCP(real-time transport control protocol)를 지원한다. RTP/RTCP를 통하여 네트워크 QoS와 관련된 정보를 획득하며 그 정보에 따라서 데이터 전송율을 조절하고 RTCP를 이용하여 에러 패킷에 대한 재전송을 사용한다. 재전송시 미디어 재생기의 버퍼링 상태와 멀티미디어 데이터의 재생시간을 고려하여 멀티미디어 데이터의 끊김이 없도록 한다.

• Proceedings of the KSPS conference
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• 2006.05a
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• pp.89-93
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• 2006

This paper presents ETRI broadcast news speech recognition system. There are two major issues on the broadcast news speech recognition: 1) real-time processing and 2) out-of-vocabulary handling. For real-time processing, we devised the dual decoder architecture. The input speech signal is segmented based on the long-pause between utterances, and each decoder processes the speech segment alternatively. One decoder can start to recognize the current speech segment without waiting for the other decoder to recognize the previous speech segment completely. Thus, the processing delay is not accumulated. For out-of-vocabulary handling, we updated both the vocabulary and the language model, based on the recent news articles on the internet. By updating the language model as well as the vocabulary, we can improve the performance up to 17.2% ERR.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.7
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• pp.2377-2389
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• 2022

At present people have higher and higher requirements for network video quality, but video quality will be impaired by various factors, so video quality assessment has become more and more important. This paper focuses on the video quality assessment method using different fuzzy neural networks. Firstly, the main factors that impair the video quality are introduced, such as unit time jamming times, average pause time, blur degree and block effect. Secondly, two fuzzy neural network models are used to build the objective assessment method. By adjusting the network structure to optimize the assessment model, the objective assessment value of video quality is obtained. Meanwhile the advantages and disadvantages of the two models are analysed. Lastly, the proposed method is compared with many recent related assessment methods. This paper will give the experimental results and the detail of assessment process.

• Journal of Ubiquitous Convergence Technology
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• v.2 no.2
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• pp.88-96
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• 2008

IPTV Content delivery systems over wired networks confront scalability problems due to their high network bandwidth requirement for real-time services. Especially, VoD service provides Trick Mode features such as pause, fast forward and similar operations. However, Trick Mode services are delivered by the method of unicast only for controlling of the stream. With a point of views, this paper propose a new real-time multimedia streaming architecture over IP Networks, which tries to achieve bandwidth efficiency and supporting for mass clients better than traditional unicast services. The proposed methods divide the Transport Stream into a series of segments. After that, this divided partial Transport Stream makes multicast streaming periodically. Meanwhile Set-top Box of a client makes a rearrangement orderly by using Presentation Time Stamp field from the served Transport Stream packets. While the current Transport Stream segment is playing, it should be guaranteed that the next segment is downloaded on time. Consequently, the original video content can be played out continuously. The detail introduction of a new real-time multimedia streaming system with analysis and simulation follows as below.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.7
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• pp.579-588
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• 2017

The purpose of this study was to examine the defibrillation efficiency according to the defibrillator type among paramedics by making a comparative analysis of the chest compression pause time and defibrillation efficiency after providing simulation education. The subjects in this study were 15 paramedics who were selected from a provincial 119 safety center. The experiment was conducted using a single-group pretest-post test design from March 2 to August 31, 2016. The collected data were analyzed by SPSS WIN 21.0, and a frequency analysis was conducted. The findings of this study were as follows: First, there was a significantly greater decrease in the chest compression pause time during CPR after providing simulation education when semi-automated defibrillators were used than when manual paddles and manual pads were employed. Second, there was a statistically significant decrease in the performance time of defibrillation when semi-automated defibrillators were used than when manual paddles and manual pads were used. The findings of this study are expected to provide paramedics with simulation education on how to promptly read ECGs using the manual mode of a semi-automated defibrillator to help more patients revive and on how to facilitate their job enlargement.

• 한국연소학회:학술대회논문집
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• 2004.11a
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• pp.231-237
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• 2004

Vacuum carburizing continues to gain acceptance as an alternative to atmosphere carburizing particularly in the car industry. The advantages of low-pressure carburization over atmospheric gas carburization is not only the creation of a surface entirely free of oxide and the environmentally friendly nature of these methods but also an improvement in deformation behaviour achieved by combining carburization with gas quenching, a reduction in batch times by increasing the carburization temperature, low gas and energy consumption and the prevention of soot to a large extent. In present study, an improved vacuum carburizing method is provided which is effective to deposit carbon in the surface of materials and to reduce cycle time. Also LPC process simulator was made to optimize to process controls parameters such as pulse/pause cycles of pressure pattern, temperature, carburizing time, diffusion time. The carburizing process was simulated by a diffusion calculation program, where as the model parameters are proposed with help the experimental results and allows the control of the carburizing process with good accordance to the practical results. Thus it can be concluded that LPC process control method based on the theoretical simulation and experimental datas appears to provide a reasonable tool for prototype LPC system.

• Proceedings of the Korean Information Science Society Conference
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• 2005.11a
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• pp.925-927
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• 2005

급속도로 IT 산업이 발전하면서, 리소스가 제한된 소형 기기들의 사용이 비약적으로 증가하는 추세이다. 자바는 플랫폼 독립성(Platform Independency), 보안성(Security), 이동성(Mobility) 등의 장점을 가지고 있기 때문에 성능을 극대화하고 안정된 서비스를 제공해야 하는 소형기기들에게 핵심 소프트웨어 플랫폼으로 많이 사용되고 있다. 임베디드 장치나 모바일 시스템과 같은 제한된 리소스를 사용하는 기기들은 자바 어플리케이션 수행을 위해 자바의 소프트웨어 플랫폼중의 하나인 K 가상 머신(K Virtual Machine: KVM)을 탑재하여 사용한다. 본 논문에서는 KVM 가비지 컬랙션의 지연 시간(Pause-Time)과 Tracing 의 수행 빈도수를 줄여 임베디드 환경에서 성능 향상을 위한 가비지 컬랙션을 설계하고 구현한 내용을 기술한다.

• International Journal of Industrial Entomology and Biomaterials
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• v.9 no.1
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• pp.107-109
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• 2004

The present investigation reports a phenomenon hitherto unknown in tropical sericulture, wherein dia-pause nature of bivoltine eggs is overcome through a cross with a non-diapausing race of silkworm, Bombyx mori, L. Eggs of bivoltine silkworm Bombyx mori, L. generally do not hatch under tropical conditions. To prevent diapause, they are subjected to acid treatment or low temperature hibernation scheduled. A race developed at KSSRDI is found to prevent the diapause nature of bivoltine eggs when crossed as male parent, without any acid treatment or hibernation schedule. This phenomenon is reported for the first time, being unique, opens up interesting area of research in silkworm genetics of commercial implications in the industry.