• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 D
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• pp.2495-2497
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• 2005

The satellite communication equipment, which has been installed and operated for the flood forecast and warning system at KOWACO, needs the review of the transmission Power control for keeping the stable operation of the satellite communication equipments. In this study, made the sample hardware for the transmission power control at Mini-Hubs and remote sites, and developed the control algorithm for stable operation of the transmission power controller.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2009년도 춘계학술대회 논문집
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• pp.84-89
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• 2009

In this paper, the experimental study on the identification of noise sources and noise transmission paths was carried out for the cabin noise control of construction equipment. In order to investigate noise and vibration characteristics of cabin structure, sound absorption, transmission, and radiation tests were performed using cabin assembly models. The noise/vibration source levels were obtained from the real cabins of wheel loader and excavator. Using transfer functions of cabins and real cabins' source data, cabin noise was decomposed into airborne and structureborne noise transmissions. Finally noise sources and major transmission paths were successfully identified for wheel loader and excavator's cabins.

• 전기의세계
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• 제28권10호
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• pp.41-47
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• 1979

The paper develops a method of minimizing power transmission losses by optimum control of reactive power flow. In the past, because the optimizing method considers as the first step the minimization of node voltage deviations and as the second step the minimization of transmission losses within the system, the calculating procedure was more complex and difficult to handle. In this paper, a new computing method for real time control on a digital computer is described which aims at a coordinated use of reactive power sources and voltage regulating devices. The power transmission losses are minimized by a gradient method while satisfying the constrained system voltage conditions and sensitivity parameters are the basis of the method.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1993년도 한국자동제어학술회의논문집(국내학술편); Seoul National University, Seoul; 20-22 Oct. 1993
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• pp.1188-1193
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• 1993

For the HST(Hydrostatic Transmission) consisted of a variable displacement axial piston pump and motor, a speed controller with efficiencies considered is proposed. To consider a efficiency in speed control, the displacements of pump and motor which maximize a steady state efficiencies with a various load torque are calculated through computer simulation and these results are reflected to speed controller which has PI control structure with cross over control scheme. It is shown through computer simulation that the proposed controller gives better steady state efficiencies compared with the conventional controller and good transient responses.

• 한국통신학회논문지
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• 제34권7B호
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• pp.677-685
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• 2009

무선 센서네트워크에서 에너지 절약을 위해 필요한 송선전력을 제어하는 기법들이 많이 연구 되었다. 그러나 기존 연구들은 송신전력제어 과정에서 최적화된 송신전력 단계를 계산하기 위해 많은 패킷이 필요하다. 본 논문에서는 추가척인 제어 패킷을 발생시키지 않고 최단경로를 고려하는 송신전력제어 기법을 제안한다. 그 기법은 네트워크 구성에 필요한 광고 메시지를 최대한 활용하여 제어 패킷을 사용하지 않으며 네트워크 구성 초기에 최대 송선전력 단계로 광고 메시지를 전달하여 구성된 최단경로를 기준으로 한다. 제안한 기법의 평가를 위해 TinyOS 에서 제안한 기법을 적용하였다. 그리고 21개의 노드를 이용하여 네트워크를 구성하고 형균 전류 소요량, 평균 네트워크 깊이 등을 측정하였다. 측정한 결과 제안한 기법을 척용한 네트워크가 이전보다 송신 시 명균 전류량이 약 24.7% 만큼 적으며 네트워크의 흡 수가 일반 네트워크 홉 수보다 약 41% 적였다.

• 한국약용작물학회지
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• 제23권4호
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• pp.284-291
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• 2015

This study was performed to investigate the effects of enhanced light transmission on plant growth, photosynthetic ability, and disease tolerance to leaf blight, anthracnose in ginseng (Panax ginseng C. A. Meyer, Araliacease family) during the early growth stage (April to June). The photosynthetic ratio, stomatal conductance, and stem diameter of plants grown under a shade net with 15% light transmission rate showed an increasing trend compared to the control plants (5% light transmission rate) although the growth of the aerial parts were not influenced significantly. Plant height, stem length, and leaf length of treated plants were not significantly different from those of the control plants. Root parameters, such as root length, diameter, and weight of treated plants increased significantly compared to the control. Yield performance ($187.4kg{\cdot}10a^{-1}$) of treated plants was 55.5% higher than that of the control ($150.4kg{\cdot}10a^{-1}$). Additionally, disease severity scores of treated plants were lower than those of the control plants, revealing higher survival rates. To retain high yield potential and enhance the level of disease tolerance in ginseng, we suggest the increase of light transmission rate during the early growth stage.

• Tuberculosis and Respiratory Diseases
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• 제79권4호
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• pp.201-206
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• 2016

Active tuberculosis (TB) has a greater burden of TB bacilli than latent TB and acts as an infection source for contacts. Latent tuberculosis infection (LTBI) is the state in which humans are infected with Mycobacterium tuberculosis without any clinical symptoms, radiological abnormality, or microbiological evidence. TB is transmissible by respiratory droplet nucleus of $1-5{\mu}m$ in diameter, containing 1-10 TB bacilli. TB transmission is affected by the strength of the infectious source, infectiousness of TB bacilli, immunoresistance of the host, environmental stresses, and biosocial factors. Infection controls to reduce TB transmission consist of managerial activities, administrative control, engineering control, environmental control, and personal protective equipment provision. However, diagnosis and treatment for LTBI as a national TB control program is an important strategy on the precondition that active TB is not missed. Therefore, more concrete evidences for LTBI management based on clinical and public perspectives are needed.

• 한국항행학회논문지
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• 제11권1호
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• pp.31-36
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• 2007

TCP(Transmission Control Protocol)는 인터넷 환경에서 널리 사용되고 있는 프로토콜의 하나이다. TCP는 흐름제어를 통해 데이터의 손실 및 재전송을 줄여 효율성을 높일 수 있으며, 이러한 흐름제어는 데이터 패킷 크기의 제한을 두는 윈도우 기법을 통해 이루어지고 있다. 흐름제어 방식에 의해 TCP는 다양한 버전으로 구분되어 있는데, 본 논문에서는 대표적인 Tahoe, Reno와 Reno의 개량형인 Newreno에 에러모델을 적용한 시뮬레이션 결과를 통해 그 성능을 분석하였다.

• Journal of Electrical Engineering and Technology
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• 제8권5호
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• pp.1096-1106
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• 2013

This paper presents the control of a Permanent Magnet Electric Variable Transmission (PM-EVT) for Hybrid Electric Vehicles (HEVs). Consisting of two electric machines, the EVT realizes the power split function in an electromagnetic way rather than in a mechanical way. A specific PM-EVT has been designed for Toyota Prius II. The control scheme of the entire vehicle is deduced using the Energetic Macroscopic Representation methodology. The energy management strategy yields local control references. A specific attention is paid for the field weakening for wide speed range. Simulation results are provided to illustrate the EVT modeling and control.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.150.2-150
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• 2001

For pneumatic system control, we need a data transmission system with high speed and reliability for information interchange between main computer and I/O devices. This paper presents a set of design techniques for a data communication system that is mainly used for pneumatic system control. For this purpose, we first designed hardware modules for an interface between central control module and local node that handles the operation of solenoid valves. In addition, we developed a communication protocol for construction of RS-485 based multi-drop network, and this protocol is basically designed with a kind of polling technique. Finally we evaluated performance of the developed system. The field test results show that, even under high noise environment, the data transmission of 375Kbps rate is ...