• 한국전자통신학회논문지
• /
• 제6권1호
• /
• pp.20-26
• /
• 2011

본 논문에서는 NM(node monitoring) 알고리듬과 NP(Piecewise Linear Function Approximation)를 사용해서 LDPC 코드 복호의 복잡도를 감소시키기 위한 효율적인 알고리듬을 제안한다. 이 NM 알고리듬은 새로운 node-threshold 방법과 message passing 알고리듬에 근거해서 제안되었는데, 이에 NP 방법을 사용해서 알고리듬의 복잡도를 더 줄일 수 있었다. 이 알고리듬의 효율성을 입증하기 위해서 모의 실험을 하였다. 모의실험결과, 기존에 잘 알려진 방법에 비해서 20% 정도 더 효율적이었다.

• Smart Structures and Systems
• /
• 제22권1호
• /
• pp.57-70
• /
• 2018

For the long-term structural health monitoring of civil structures, the effect of ambient temperature variation has been regarded as one of the critical issues. In this study, a principal component analysis (PCA)-based algorithm is proposed to filter out temperature effects on electromechanical impedance (EMI) monitoring of prestressed tendon anchorages. Firstly, the EMI monitoring via a piezoelectric interface device is described for prestress-loss detection in the tendon anchorage system. Secondly, the PCA-based temperature filtering algorithm tailored to the EMI monitoring of the prestressed tendon anchorage is outlined. The proposed algorithm utilizes the damage-sensitive features obtained from sub-ranges of the EMI data to establish the PCA-based filter model. Finally, the feasibility of the PCA-based algorithm is experimentally evaluated by distinguishing temperature changes from prestress-loss events in a prestressed concrete girder. The accuracy of the prestress-loss detection results is discussed with respect to the EMI features before and after the temperature filtering.

• 자동차안전학회지
• /
• 제16권2호
• /
• pp.51-59
• /
• 2024

This study presents a method for health monitoring of rotating objects for mobility based on multiple recursive least squares(RLS) algorithms. The performance degradation of the rotating objects causes low handing / low driving performances and even fatal accidents. Therefore, health monitoring algorithm of rotating objects is one of the important technologies for mobility fail-safe and maintenance areas. In order for health monitoring of rotating objects, four recursive least squares algorithms with forgetting factor were designed in this study. The health monitoring algorithm proposed in this study consists of two steps such as uncertainty estimation and parameter changes estimation. In order to improve estimation accuracy, time delay function was applied to the estimated signals based on the first order differential equation and forgetting factors used for the RLS were reasonably tuned. The health monitoring algorithm was constructed in Matlab/Simulink environment and simulation-based performance evaluation was conducted using DC motor model. The evaluation results showed that the proposed algorithm estimates the actual parameter differences reasonably using velocity and current information.

• Journal of Advanced Marine Engineering and Technology
• /
• 제29권5호
• /
• pp.579-586
• /
• 2005

Recently, it has demanded to the wireless monitoring system in stand-alone PV power generation system. We propose the multiplex monitoring method using RF unit of low-price. RF unit consists of RF modem and communication controller. It is also able to use by repeater to communicate long distance. In this paper. two algorithms were programmed by CCS-C and C++ for multiplex monitoring method, The algorithm of choosing unit was used 'select and poll method' and the course assignment algorithm was embodied with 'Bellman-Ford algorithm'. The good result was achieved in the actual test without communication-data lose. The proposed method will be applied such as monitoring system of PV light on the wayside, monitoring system of unmanned lighthouse, monitoring system of refrigeration container on vessel and so on. It can be applied in the field that various ocean energy system.

• 대한임베디드공학회논문지
• /
• 제10권4호
• /
• pp.213-219
• /
• 2015

Real-time energy monitoring systems is a demand-response system which is reported to be effective in saving energy up to 12%. Real-time energy monitoring system is commonly composed of smart-plugs which sense how much electrical power is consumed and IHD(In-Home Display device) which displays power consumption patterns. Even though the monitoring system is effective, users should themselves match which smart plus is connected to which appliance. In order to make the matching work to be automatic, the monitoring system need to have appliance identification algorithm, and some works have made under the name of NILM(Non-Intrusive Load Monitoring). This paper proposed an algorithm which utilizes multiple classifiers to improve accuracy of appliance identification. The algorithm proposes to understand each classifiers performance, that is, when a classifier make a result how much the result is reliable, and utilize it in choosing the final result among result candidates from many classifiers. By using the proposed algorithm this paper make 4.5% of improved accuracy with respect to using single best classifier, and 2.9% of improved accuracy with respect to other method using multiple classifiers, so called CDM(Commitee Decision Mechanism) method.

• 한국기계가공학회지
• /
• 제10권5호
• /
• pp.13-19
• /
• 2011

In this paper, the active monitoring and control system is developed. This system can monitor the status of high the speed spindle in real time during its processing, and can analyze its influence of dimensional accuracy and processing if any, and can control the machining condition to realize the machining system equipped with active monitoring and self-diagnostic features. Machining experiment was performed on 3 materials Al, Brass and S45C in order to derive the relation between active monitoring and control algorithm by the machining load. In addition, we measured surface roughness of processing specimen along with the data change of spindle rotating speed and conveying speed according to variation of machining load. Based on these experiments, we derived relations for each material that can be applied to the control algorithm to allow self control of the rotating speed and conveying speed according to the machining load.

• 한국통신학회논문지
• /
• 제33권10A호
• /
• pp.987-996
• /
• 2008

본 논문에서는 기존 리더 충돌방지 알고리즘인 Channel Monitoring 알고리즘, Pulse Protocol 알고리즘에 대하여 살펴보고, 태그인식시간을 감소시키고, 데이터 처리량, 시스템 효율을 증가 시킬 수 있는 슬롯 점유확률을 이용한 Pulse Protocol 기반의 Hybrid 리더 충돌 방지 알고리즘을 제안한다. 제안하는 알고리즘은 Pulse Protocol 알고리즘의 성능을 향상시키기 위하여 Channel Monitoring 알고리즘에서 사용되고 있는 슬롯의 점유확률 (Occupied Probability)을 이용한다. 즉, 리더들은 랜덤 backoff 시간을 생성한 후, 자신이 사용하게 될 슬롯의 점유확률을 확인하고, 이 슬롯의 점유확률이 0보다 크다면, 새로운 랜덤 backoff 시간을 생성하여 리더간의 충돌을 피한다. 기존 알고리즘들과 제안하는 알고리즘과의 성능을 태그인식시간, 데이터 처리량 및 시스템 효율 등의 성능분석항목들을 통하여 비교 및 분석하여, 제안하는 알고리즘에 의하여 리더의 개수가 증가함에 따라 7% 정도의 태그인식시간 및 데이터 처리량 성능 향상을 확인한다.

• 통합자연과학논문집
• /
• 제10권3호
• /
• pp.162-170
• /
• 2017

In this paper, it is aim to implement a wheelchair monitoring system that provides users with customized medical services easily in everyday life, together with mobility guarantee, which is the most basic requirement of the elderly and disabled persons with physical disabilities. The case-based intelligent wheelchair monitoring system proposed in this study is based on a case-based k-NN algorithm, which implements a system for constructing and inferring examples of various biometric and environmental information of wheelchair users as a knowledge database and a monitoring interface for wheelchair users. In order to confirm the usefulness of the case-based k-NN algorithm, the SVM algorithm showed an average accuracy of 84.2% and the average accuracy of the proposed case-based k-NN algorithm was 86.2% And showed higher performance in terms of accuracy. The system implemented in this paper has the advantage of measuring biometric information and data communication regardless of time and place and it can provide customized service of wheelchair user through user friendly interface.

• 한국정보통신학회:학술대회논문집
• /
• 한국정보통신학회 2017년도 춘계학술대회
• /
• pp.236-237
• /
• 2017

최근 많은 산업용 기기들은 외부 모니터링과 제어 시스템에 프로토콜 호환성 문제에 직면하고 있다. 본 논문은 산업용 데이터의 모니터링을 지원하기 위하여 사용자가 프로그램을 통하여 여러 통신프로토콜의 지원이 가능하도록 통신 프로토콜 변환 알고리즘을 구현하였다. 구현된 알고리즘을 이용하여 통신 게이트웨이 모듈을 통한 변환 실험을 진행하였고 좋은 결과를 얻었다.

• 한국정보통신학회:학술대회논문집
• /
• 한국정보통신학회 2016년도 추계학술대회
• /
• pp.283-284
• /
• 2016

최근 많은 산업용 기기들은 외부 모니터링과 제어 시스템에 프로토콜 호환성 문제에 직면하고 있다. 본 논문은 산업용 데이터의 모니터링을 지원하기 위하여 사용자가 프로그램을 통하여 여러 통신 프로토콜의 지원이 가능하도록 통신 프로토콜 변환 알고리즘을 구현하였다. 구현된 알고리즘을 이용하여 통신 게이트웨이 모듈을 통한 변환 실험을 진행하였고 좋은 결과를 얻었다.