• Journal of Information Processing Systems
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• 제13권5호
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• pp.1358-1371
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• 2017

Dynamic thermal rating (DTR) system is an effective method to improve the capacity of existing overhead line. According to the methodology based on CIGRE (International Council on Large Electric systems) standard, ampacity values under steady-state heating balance can be calculated from ambient environmental conditions. In this study, simulation analysis of relations between parameters and ampacity is described as functional dependence, which can provide an effective basis for the design and research of overhead transmission lines. The simulation of ampacity variation in different rating scales is described in this paper, which are determined from real-time meteorological data and conductor state parameters. To test the performance of DTR in different rating scales, capacity improvement and risk level are presented. And the experimental results show that the capacity of transmission line by using DTR has significant improvement, with low probability of risk. The information of this study has an important reference value to the operation management of power grid.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.652-657
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• 2004

As the real-time multimedia applications through Internet increase, the bandwidth available to TCP connections is oppressed by the UDP traffic, result in the performance of overall system is extremely deteriorated. Therefore, developing a new transmission protocol is necessary. The TCP-friendly algorithm is an example meeting this necessity. The TCP-friendly (TFRC) is an UDP-based protocol that controls the transmission rate based on the available round transmission time (RTT) and the packet loss rate (PLR). In the data transmission processing, transmission rate is determined based on the conditions of the previous transmission period. If the one-step ahead predicted values of the control factors are available, the performance will be improved significantly. This paper proposes a prediction model of transmission rate control factors that will be used for the transmission rate control, which improves the performance of the networks. The model developed through this research is predicting one-step ahead variables of RTT and PLR. A multiplayer perceptron neural network is used as the prediction model and Levenberg-Marquardt algorithm is used for the training. The values of RTT and PLR were collected using TFRC protocol in the real system. The obtained prediction model is validated using new data set and the results show that the obtained model predicts the factors accurately.

• 한국위성정보통신학회논문지
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• 제9권3호
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• pp.47-52
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• 2014

본 논문은 이미지 처리 기술을 이용한 광 카메라 통신(OCC: Optical Camera Communications) 기술을 제안한다. OCC 시스템의 구조 및 동작을 제안한다. 상용 30fps 카메라의 샘플링 동작에 의해 제한되는 데이터율을 증가시키기 위해 칼라 이미지 처리기술을 이용한 멀티칼러 전송기법을 제안한다. 멀티칼라 부호화 및 이미지 처리기반의 복호화 기법을 제안한다.

• 융합신호처리학회 학술대회논문집
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• 한국신호처리시스템학회 2000년도 하계종합학술대회논문집
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• pp.257-260
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• 2000

In modern battlefield situation, radar and infrared sensors may be located on aircraft having limited computational resources available for real-time computer processing. Hence sensor images are transmitted typically to central stations for processing and automatic target recognition/detection. Owing to the limited bandwidth channels that are typically available between the aircraft and processing stations, images are compressed prior to transmission to facilitate rapid transfer. In this paper we examine the problem of compressing sensor data for transmission, given that target recognition is the end goal. Performance result shows that the front-end target recognition system achieves a relatively high level of performance as well as a high compression ratio.

• 대한의용생체공학회:의공학회지
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• 제12권2호
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• pp.113-120
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• 1991

This paper describes the implementation of a 3 channel ECG monitoring system. This system consists of an IBM-PC and simple accessory only. A PDTS (parallel data transmission system ) was designed to do monitor the data being operated with no effect and no exchange of software and hardware on the main transmission system in LOCAL mode. And it receives patient's ECG data from EPTS ( ECG processing and transmission system) of distant region. It provides on-line ECG waveform display, waveform storage, recall and editing the waveform. We have implemented the monitoring system by tw methods, and with system, we could directly monitor the EPTS and also receive the data from the remote ㅁe잉ion. This system was tested by experiments and examined its practical use.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2011년도 추계학술발표대회
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• pp.355-356
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• 2011

LiDAR data is very large, which contains an amount of redundant information. The information not only takes up a lot of storage space but also brings much inconvenience to the LIDAR data transmission and application. Therefore, a simplified method was proposed for LiDAR data based on quad-tree structure in this paper. The boundary contour lines of the buildings are displayed as building extraction. Experimental results show that the method is efficient for point's simplification according to the rule of mapping.

• 융합신호처리학회논문지
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• 제2권3호
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• pp.32-38
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• 2001

다중 채널을 사용하는 디지털 멀티톤 데이터 전송 시스템의 성능은 전송 채널의 영향으로 발생하는 심벌간의 간섭 잡음에 제한적이다. ISI를 제한하여 시스템의 데이터 전송 성능을 향상시키는 목적으로 전송 채널 임펄스 응답의 길이를 단축시키는 기법과 전송 채널의 주파수 특성을 향상시키는 기법을 합성하는 채널 등화 기법을 제안하였다. 수렴 속도가 빠른 칼만 알고리즘 및 구현 상 효율적인 LMS 알고리즘을 적용하여 제안한 등화기를 구현한다. 구현된 등화기를 필터 뱅크 기반 다중반송파 데이터 전송 시스템에 적용한 결과, 기존의 시스템의 성능보다 우수한 신호 대 간섭 잡음 비를 얻을 수 있음을 컴퓨터 시뮬레이션을 통하여 확인하였다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2004년도 ICEIC The International Conference on Electronics Informations and Communications
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• pp.302-309
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• 2004

The transmission capacity of wireless communication systems may become dramatically high by employ multiple transmit and receive antennas with space-time coding techniques appropriate to multiple transmit antennas. For large number of transmit antennas and at high bandwidth efficiencies, the receiver may become too complex whenever correlation across transmit antennas is introduced. Reducing decoding complexity at receiver by combining array processing and space-time codes (STC) helps a communication system using STC to overcome the big obstacle that prevents it from achieving a desired high transmission rate. Multi-carrier CDMA (MC-CDMA) allows providing good performance in a channel with high inter-symbol interference. Antenna array, STC and MC-CDMA system have a similar characteristic that transmit-receive data streams are divided into sub-streams. Thus, there may be a noticeable reduction of receiver complexity when we combine them together. In this paper, the combination of array processing and STC in MC-CDMA system over slow selective-fading channel is investigated and compared with corresponding existing MC-CDMA system using STC. A refinement of this basic structure leads to a system design principle in which we have to make a trade off between transmission rate, decoding complexity, and length of spreading code to reach a given desired design goal.

• Journal of Communications and Networks
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• 제11권2호
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• pp.196-206
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• 2009

Over the last five years, relaying or multihop techniques have been intensively researched as means for potentially improving link performance of wireless networks. However, the data rates of relays are often limited because they cannot transmit and receive on the same frequency simultaneously. This limitation has come to the attention of researchers, and recently a number of relay techniques have been proposed specifically to improve the data efficiency of relaying protocols. This paper surveys transmission protocols that employ first single relays, then multiple relays and finally multiple antenna relays. A common feature of these techniques is that novel signal processing techniques are required in the relay network to support increased data rates. This paper presents results and discussion that highlight the advantages of these approaches.

• 제어로봇시스템학회논문지
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• 제18권1호
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• pp.13-20
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• 2012

This paper proposes a marine engine state monitoring system using a DPQ (Distributed Precedence Queue) mechanism which collects the state of bearings, temperature and pressure of engine through the CAN network. The CAN is developed by Bosch Corp. in the early 1980' for automobile network. The data from various sensors attached in the marine engine are converted to digital by the analog to digital converter and formatted to fit the CAN protocol at the CAN module. All the CAN modules are connected to the SPU (Signal Processing Unit) module for the efficient communication and processing. This design reduces the cost for wiring and improves the data transmission reliability by recognizing the sensor errors and data transmission errors. The DPQ mechanism is newly developed for the performance improvement of the marine engine system, which is demonstrated through the experiments.