• 인터넷정보학회논문지
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• 제16권5호
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• pp.11-17
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• 2015

웨어러블 센서 시스템에서 사용하는 일반적인 전송 전력 조절 모델에서는 수신 패킷의 RSSI가 Target RSSI Margin을 벗어나면 전송 전력 조절 알고리즘을 이용하여 새로운 전송 전력을 찾는다. 이 때 싱크 노드가 센서 노드에게 새로이 계산된 전송 전력을 전달하기 위해 제어 패킷을 보낸다. 그런데 무선 네트워크의 채널 상태가 좋지 않을 때는 제어 패킷을 많이 소모하면서도 적정 전송 전력을 찾지 못해 에너지 낭비만 하게 된다. 따라서 본 논문에서 무선 네트워크 채널 환경이 안정적이라고 판단되었을 때 전송 전력을 변경하는 새로운 제어 패킷 전송 결정 기법을 제안한다. 제안되는 기법으로 낭비되는 에너지를 줄일 수 있다. 제안하는 기법을 평가하기 위해 본 논문에서는 Binary 전송 전력 조절 알고리즘에 제어 패킷 전송 결정 기법을 적용하고 그 결과를 분석한다. 채널의 상태를 판단하는 방안을 3가지 제안하여 실험하고 결과를 분석한다.

• 전자공학회논문지S
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• 제36S권11호
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• pp.9-14
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• 1999

본 논문은 10Gbps 광 전송 장치의 저속부와 고속부 셀프 간에 77.76Mbps의 10라인의 전송 방법인 H-BUS 방식보다 효율적인 622Mbps 의 1라인으로 전송하기 위하여 622Mbps로 수신되는 데이터를 동기식 디지털 계위(SDH)에 정의된 동기식 전달방식(STM)-64 프레임 형태로 정렬할 수 있는 리프레임 방법을 설명하였으며 이를 VHDL로 설계하여 10Gbps 광 전송 장치의 T14U 보드의 10G-S4 ASIC내에 적용하였다.

• 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.

• 대한전기학회논문지:전력기술부문A
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• 제53권5호
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• pp.296-301
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• 2004

The Available Transfer Capability (ATC) is defined as the measure of the transfer capability remaining in the physical transmission network for further commercial activity above already committed uses. Available Transfer Capability (ATC) calculation is a complicated task, which involves the determination I of total transfer capability (TTC), transmission reliability margin (TRM) and capability benefit margin (CBM). As the electrical power industry is restructured and the electrical power exchange is updated per hour, it is important to accurately and rapidly quantify the available transfer capability (ATC) of the transmission system. In ATC calculation,. the existing CPF method is accurate but it has long calculation time. On the contrary, the method using PTDF is fast but it has relatively a considerable error. This paper proposed QFA method, which can reduce calculation time comparing with CPF method and has few errors in ATC calculation. It proved that the method can calculate ATC more fast and accurately in case study using IEEE 24 bus RTS.

• 대한전기학회논문지:전력기술부문A
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• 제54권12호
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• pp.573-579
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• 2005

Dynamic analysis of a transmission line which is compensated by a FACTS device such as STATCOM, SSSC and UPFC is carried out in this paper and the impacts on conventional line protection methods such as the DCPM (Differential Current Protection Method) and the DPM (Distance Protection Method) are reviewed. A refined DCRM is proposed to detect faults properly regardless of the FACTS operation. The proposed method is applied to a FACTS-compensated line with a variety of faults and is verified by simulation results. An adaptive DPM on a FACTS-compensated line was proposed previously in the literature. In order to emphasize the necessity of the modified DPM, the conventional DPM is applied to a FACTS-compensated system. Significant factors such as fault types, fault locations, and fault resistances as well as FACTS device types are considered for relaying setting.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2000년도 추계학술대회논문집
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• pp.409-414
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• 2000

A new impedance tube method is presented for the measurement of transmission loss of sound isolation sheets. The two-microphone method based on the sound decomposition theory proposed by Seybert and Ross is reviewed in this impedance tube method, which has been used for the determination of absorption coefficient of absorptive materials as well as transmission loss of automotive mufflers. Sound transmission losses for rubber, polyvinyl and asphalt sheets are measured in an impedance tube and reverberation room facility, respectively. By comparing two measurement methods, the reliability of impedance tube method used in this study is validated. From the experimental results, it is shown that the accuracy of sound isolation capability obtained by the impedance tube method depends upon the microphone spacing and the distance of the first microphone from the test sample surface.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 심포지엄 논문집 정보 및 제어부문
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• pp.178-180
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• 2007

In this paper, a real-time transmission algorithm based on IEEE 802.15.4 is proposed. The superframe of IEEE 802.15.4 is applied to the transmission method of real-time mixed data (periodic data, sporadic data, and non real-time message). The simulation results show the real-time performance of sporadic data is improved by using the proposed transmission algorithm.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 추계학술대회 논문집 전력기술부문
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• pp.171-173
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• 2002

This paper presents a power system decomposition technique for digital simulation of large power system. To decompose power system, distributed transmission line model is used. But this model can be used only for long transmission lines. In this paper, capacitor compensation method is proposed to use distributed transmission line model for short transmission line. And case study shows proposed method can be used for effective power system decompositon in digital simulation of large power system.

• 전기의세계
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• 제29권6호
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• pp.401-409
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• 1980

This paper deals with the implementation of forced reclosing the transmission line. Because the ground circuit breaker method decrease the secondary arc current sufficiently, the reclosing time can be reduced. As the secondary arc current is large and its residual time is long in UHV transmission line, this method is more effective in that system. The resistance of ground circuit breaker which minimize the secondary arc current is determined according to the system voltage and the length of transmission line.

• 대한전기학회논문지
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• 제40권12호
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• pp.1296-1301
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• 1991

This paper presents a hybrid image mode Galerkin method for the analysis of the transmission line structures suspended between infinite parallel ground planes. A Green's function that consists of numerically accelerated image mode terms is developed, which is used in boundary integral equation. Transmission lines of arbitrary cross section are analyzed using Galerkin's method. Two kinds of configurations of transmission lines are studied in sample problems.