• 대한산업공학회지
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• 제14권1호
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• pp.1-15
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• 1988

DS1 transmission systems use framing bit errors, bipolar violations and code-detected errors to estimate the bit error rate when determining errored and severely errored seconds. Using the coefficient of variation under the memoryless binary symmetric channel assumption, a basic framework to evaluate these estimation schemes is proposed to provide a practical guideline in determining errored and severely errored seconds which are fundamental in monitoring the real-ime error performance of DS1 transmission systems carrying live traffic. To evaluate the performance of the cyclic redundancy check code (CRC), a computer simulation model is used. Several drawbacks of the superframe format in association with real time error performance monitoring are discussed. A few recommendations are suggested in measuring errored and severely errored seconds, and determining service limit alarms through the use of the superframe format. Furthermore, we propose a new robust scheme for determining service limit alarms which take into consideration the limitations of some estimation schemes for the time interval of one second.

• 설비공학논문집
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• 제19권10호
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• pp.703-709
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• 2007

Much energy is used in occupying stage of the Building Life Cycle. Electric charge is one of the various factors that influence on energy use of residents. This study focused on electric charge and searched that whether electric charge affects residents' behavior of operating air conditioner and their controlled indoor climate. We surveyed three groups for field study ; A group is residents who live in a studio apartment, B group is residents who live in a university dormitory and C group is residents who live in a apartment with their family. The A and C groups are charged for electric as energy consumption they used. And the B group is students who live in a university dormitory and they are not charged for their energy consumption. We measured the time to use the air conditioner for cooling, on/off temperature of air conditioner, and room air temperature for these three groups. The result shows that consideration for electric charge affects to the residents' behavior of operating air conditioner and their acceptable thermal range.

• 한국인터넷방송통신학회논문지
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• 제16권5호
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• pp.165-172
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• 2016

본 논문은 Raspberry Pi 3 임베디드 컴퓨터를 이용한 스트리밍 시스템의 구현 사례를 소개한다. 본 연구에서 구현한 스트리밍은 파일 전송 방식이 아닌 라이브 스트리밍 시스템이다. 오디오 입력 단자로부터 받은 아날로그 신호를 wav 형식으로 변환하여 서버에 접속한 다수의 사용자에게 동시에 방송하는 푸시형 멀티스레드 스트리밍이다. 스트리밍 서버 소프트웨어는 전체 자바 언어로 구현하였기 때문에 Raspberry Pi 3 가 아닌 다른 임베디드 컴퓨터에도 수정 없이 탑재될 수 있다. 계산과 실험을 통해 분석한 결과 최대 65여명을 동시 스트리밍 할 수 있다. 그리고 오디오 소스로부터 청취 단말기의 재생까지의 시간 지연은 40ms 남짓되는 것으로 평가되었다.

• 디지털융복합연구
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• 제13권11호
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• pp.141-148
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• 2015

기존 비디오 라이브 스트리머에 비해서 매우 저렴하고 저전력으로 휴대용으로 쉽게 동작하는 HLS(Http Live Streaming) 전송기를 임베디드 리눅스 기반으로 개발 및 구현하였다. HLS 전송기를 저렴하게 구현하기 위해 Arm11 프로세서 위에 임베디드 리눅스를 운영체제로 포팅 하였고 오픈 소스인 FFmpeg와 Segmenter을 이용하여 HLS 프로토콜을 구현하였다. 노트북, iPhone, android phone, 노트북을 수신단말기로 이용하여 개발한 임베디드 리눅스 기반의 휴대용 HLS 전송기의 성능을 평가하였다. 본 논문에서 개발한 HLS 전송기는 애플사가 제안한 HLS 권고 규격 이상의 성능을 구현하였음을 성능평가 실험을 통해 확인하였다. 본 논문에서 개발한 제품의 활용분야는 실시간으로 현장의 위급상황을 현지 지휘소나 원거리 사령부에 전달해야하는 경우 HLS를 개인이 착용하여 이동하면서 실시간으로 상황영상을 전달하는 분야에 활용될 수 있을 것으로 생각된다.

• 한국산업정보학회논문지
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• 제29권2호
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• pp.81-99
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• 2024

최근, 실시간으로 스트리머와 소비자간 특정 제품에 대한 소통을 지원하는 라이브 커머스가 급격히 성장하고 있다. 라이브 커머스는 시각적으로 제품 활용 방법 등을 제공함으로써, 소비자의 합리적 제품 구매를 돕는 비즈니스 모델을 갖추고 있다. 연구의 목적은 소비자가 라이브 커머스에서 느낄 수 있는 불확실성 요소를 제시하고, 스트리머와 플랫폼의 불확실성 감소를 위한 지원 방법을 제시하는 것이다. 연구는 선행연구를 통해 연구 가설을 수립하였으며, 20세 이상의 라이브 커머스를 경험한 이력이 있는 소비자로부터 설문을 받아 가설 검정에 적용하였다. 분석 결과, 스트리머의 자원 원천 신뢰성(신뢰성, 전문성, 평판)이 스트리머 불확실성을 감소시켜 구매 의도에 영향을 주는 것으로 나타났다. 또한, 플랫폼의 반품정책이 소비자의 제품 불확실성과 상호작용 효과를 가져 구매 의도에 영향을 주었다. 연구는 라이브 커머스 소비자의 제품 구매 과정에서의 불확실성 감소 방향을 제시함으로써, 라이브 커머스 플랫폼의 맞춤형 서비스 전략 수립에 기여한다.

• 대한안전경영과학회지
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• 제16권2호
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• pp.43-52
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• 2014

In weapon systems development, live fire tests have been frequently adopted to evaluate the performance of the systems under development. Therefore, it is necessary to ensure safety in the test ranges where the live fire tests can cause serious hazards. During the tests, a special care must be taken to protect the test and evaluation (T&E) personnel and also test assets from potential danger and hazards. Thus, the development and management of the range safety process is quite important in the tests of guided missiles and artillery considering the explosive power of the destruction. Note also that with a newly evolving era of weapon systems such as laser, EMP and non-lethal weapons, the test procedure for such systems is very complex. Therefore, keeping the safety level in the test ranges is getting more difficult due to the increased unpredictability for unknown hazards. The objective of this paper is to study on how to enhance the safety in the test ranges. To do so, an approach is proposed based on model-based systems engineering (MBSE). Specifically, a functional architecture is derived utilizing the MBSE method for the design of the range safety process under the condition that the derived architecture must satisfy both the complex test situation and the safety requirements. The architecture developed in the paper has also been investigated by simulation using a computer-aided systems engineering tool. The systematic application of this study in weapon live tests is expected to reduce unexpected hazards and test design time. Our approach is intended to be a trial to get closer to the recent theme in T&E community, "Testing at the speed of stakeholder's need and rapid requirement for rapid acquisition."

• 지역사회간호학회지
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• 제14권3호
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• pp.445-456
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• 2003

Purpose: This study attempted to propose the basic framework for spiritual nursing intervention by understanding live spiritual experiences of terminal cancer patients. The study duration was from July 2002 to January 2003, and the subjects of this study were patients who were expected to live less than six months. The number of subjects was six and the average time of each interview was about an hour. Method: The data were analyzed using the method of phenomenological study analysis, which Colaizzi (1978) proposed. Result: Through live spiritual experiences. terminal cancer patients showed complex emotion about the Absolute, human, disease, and death: depended on the Absolute through recognizing death and spiritual acknowledgement: recollected the past life: accepted death believing salvation and immortality: recovered relationships with others through forgiving and reconciling with the Absolute and neighbors. Also, they pursued the meaning of pain. death, and life while feeling pain: demanded love and concern to the Absolute and neighbors: had a sense of futility about life and a hope for the future life: transcendental energy towards the world after death. Wishing to have a peaceful end to life. they felt peaceful and comfortable. Conclusion: Terminal cancer patients want to meet a peaceful end to life with a hope for the future and accept the meaning of death with peace and comfort minds(##-minds), which will allow them to carry on peaceful and satisfactory days for the rest of their lives. Thus, it is very important for caregivers to let them have spiritual experiences and care for them.

• 천문학회보
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• 제42권1호
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• pp.31.2-31.2
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• 2017

The central regions of barred-spiral galaxies contain interesting gaseous structures such as dust lanes and nuclear rings with intense star formation. While our previous studies were useful in understanding the formation of these structures star formation history, they were limited to 2D isothermal galaxies in which the stellar disk and halo are modeled by fixed gravitational potentials. To study the effects of bar growth as well as the vertical dimension, we use the mesh-free hydrodynamic code named GIZMO and run 3D simulations by treating the stellar disk and halo as being live. We find that the new 3D models form the gaseous features similarly to the previous 2D models, although the detailed formation processes are quite different. For example, a ring has a large radius when it first forms and shrinks over time in the previous 2D models. In the 3D live-potential models, however, a ring forms small and grows in size with time. We present the results of the new simulations and discuss them in comparison with the previous 2D results.

• 한국인터넷방송통신학회논문지
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• 제12권5호
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• pp.275-281
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• 2012

스마트폰의 대중화로 모바일기기에서의 음악을 듣기 위한 스트리밍 서비스가 주요시 되고 있다. 애플 iOS에서는 Apple의 HTTP Live Streaming 방식을 사용하고 안드로이드에서는 RTSP(Real-time Streaming Protocol) 방식을 사용한다. 모바일 실시간 스트리밍을 지원하기 위해 와우자 미디어 서버를 사용하게 되는데, 이는 애플과 안드로이드 모바일 스트리밍 모두를 지원한다. 본 논문에서는 스마트폰 자체의 녹음 기능을 통해 유저 스스로가 노래를 녹음하고, 이를 스트리밍 서버에 업로드 하여 유저가 선택한 노래를 실시간으로 스트리밍 모바일 재생 서비스가 가능하고, 노래공유 SNS 기능을 제공하는 스마트폰 앱의 설계 및 구현에 대해 기술하고자 한다.

• Asian-Australasian Journal of Animal Sciences
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• 제13권11호
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• pp.1604-1608
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• 2000

Penicillin antibiotics such as penicillin G, ampicillin and amoxicillin have been widely used in the pig industry to control salmonellosis, bacterial pneumonia, and urinary tract infections. Extensive use of antibiotics in veterinary clinics has resulted in tissue residues and bacterial resistance. To prevent unwanted drug residues entering the human food chain, extensive control measures have been established by both government authorities and industries. The demands for reliable, simple, sensitive, rapid and low-cost methods for residue analysis of foods are increasing. In this study, we established a rapid prediction test for the detection of pigs with unacceptable tissue residues of penicillins. The recommended therapeutic doses of three penicillins, penillin G (withdrawal time, 7 days), ampicillin (withdrawal time, 7 days) and amoxicillin (withdrawal time, 14 days), were administered to three groups of 20 pigs each. Blood was sampled before drug administration and during the withdrawal period. The concentration of penicillins in plasma, determined by a semi-quantitative ELISA, were compared to that of internal standard, 4 ppb, which corresponded to the Maximum Residue Limit in milk. The absorbance ratio of internal standard to sample (B/Bs) was employed as an index to determine whether drug residues in pig tissues were negative or positive. That is, a B/Bs ratio less than 1 was considered residue positive, and larger than 1 negative. All 60 plasma samples from pigs were negative to three penicillins at pretreatment. Penicillin G could be detected in the plasma of the treated pigs until day 4 post-treatment and ampicillin until day 2, whereas amoxicillin could be detected until day 10 of its withdrawal period. The present study showed that the semi-quantitative ELISA could be easily adapted to detect residues of penicillin antibiotics (penicillin G, ampicillin and amoxicillin) in live pigs.