• Proceedings of the Korean Society of Precision Engineering Conference
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• 1993.10a
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• pp.70-75
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• 1993

Chatter vibration is an unwanted phenomenon in metal cutting and it always affects surface finish, tool life machine life and the productivity of machining process. The In-process monitoring & control of chatter vibration is necessarily required to automation system. In this study, we constructed the multi-sensing system using Tool Dynamometer,Accelerometer and AE(Acoustic Emission) sensor for the credible detection of chatter vibration. And a new approach using a neural network to process the features of multi-sensor for the recognition of chatter vibration in turning operation is proposed. With the back propagation training process, the neural network memorize and classify the feature difference of multi-sensor signals.

• International Journal of Contents
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• v.12 no.1
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• pp.44-48
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• 2016

Driver fatigue is a major cause of fatal road accidents and has significant implications in road safety. In recent years, researchers have investigated steering wheel grip force as an alternative method to detect driver fatigue noninvasively and in real time. In this study, a fatigue detection system was developed by monitoring the grip force and changes in the grip force were measured while participants' engaged in an interactive simulated driving task. The study also measured the participants' subjective sleepiness to ensure the validity of measuring grip force. The results indicated that while participants engaged in a driving task, steering wheel grip force decreased and subjective sleepiness increased concurrently over time. The possible applications of the driver fatigue detection system by steering wheel grip force and future guidelines are discussed.

• Proceedings of the KIEE Conference
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• 2002.11d
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• pp.372-374
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• 2002

In this paper, we studied for performance of traction and braking for on-line test and evaluation of korean high speed rail vehicle. It is composed of 6 DAMs(Data Acquisition Modules), 2 monitoring modules and 1 main computer. The software should set and control the hardware of the measuring system, perform the analysis and calculation of measuring data and interface between users and the measuring system. As a result, It has been shown a good performance of traction and braking for test vehicle.

• Korean Journal of Remote Sensing
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• v.38 no.1
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• pp.111-126
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• 2022

Land use and land cover (LULC) mapping is an important factor in geospatial analysis. Although highly precise ground-based LULC monitoring is possible, it is time consuming and costly. Conversely, because the synthetic aperture radar (SAR) sensor is an all-weather sensor with high resolution, it could replace field-based LULC monitoring systems with low cost and less time requirement. Thus, LULC is one of the major areas in SAR applications. We developed a LULC model using only KOMPSAT-5 single co-polarized data and digital elevation model (DEM) data. Twelve HH-polarized images and 18 VV-polarized images were collected, and two HH-polarized images and four VV-polarized images were selected for the model testing. To train the LULC model, we applied the conditional generative adversarial network (cGAN) method. We used U-Net combined with the residual unit (ResUNet) model to generate the cGAN method. When analyzing the training history at 1732 epochs, the ResUNet model showed a maximum overall accuracy (OA) of 93.89 and a Kappa coefficient of 0.91. The model exhibited high performance in the test datasets with an OA greater than 90. The model accurately distinguished water body areas and showed lower accuracy in wetlands than in the other LULC types. The effect of the DEM on the accuracy of LULC was analyzed. When assessing the accuracy with respect to the incidence angle, owing to the radar shadow caused by the side-looking system of the SAR sensor, the OA tended to decrease as the incidence angle increased. This study is the first to use only KOMPSAT-5 single co-polarized data and deep learning methods to demonstrate the possibility of high-performance LULC monitoring. This study contributes to Earth surface monitoring and the development of deep learning approaches using the KOMPSAT-5 data.

• 제어로봇시스템학회:학술대회논문집
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• 1991.10b
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• pp.1570-1575
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• 1991

The feasibility of using an adaptive resonance network (ART2) with unsupervised learning capability for too] wear detection in turning operations is investigated. Specifically, acoustic emission (AE) and cutting force signals were measured during machining, the multichannel AR coefficients of the two signals were calculated and then presented to the network to make a decision on tool wear. If the presented features are significantly different from previously learned patterns associated with a fresh tool, the network will recognize the difference and form a new category m worn tool. The experimental results show that tool wear can be effectively detected with or without minimum prior training using the self-organization property of the ART2 network.

• Proceedings of the Korea Information Processing Society Conference
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• 2002.11c
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• pp.1685-1688
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• 2002

모바일 장비의 발달로 인하여 무선 통신 기술을 이용한 서비스들이 증가하고 있으며 차량위치 추적 서비스 분야에서도 PDA와 같은 모바일 장비를 사용한 차량 위치 모니터링 서비스가 요구되고 있다. 이 논문에서는 PDA를 이용하여 실시간으로 차량의 위치를 모니터링 할 수 있는 시스템을 구현하였다. 시스템은 차량의 위치 정보를 저자 관리하는 차량 위치 모니터링 할 수 있는 시스템을 구현하였다. 시스템은 차량의 위치 정보를 저장 관리하는 차량 위치 모니터링 서버와 차량의 위치관련 정보를 제공하는 PDA 클라이언트로 구성하였다. 구현된 시스템은 PDA 클라이언트를 이용하여 실시간으로 이동 차량의 시간 및 구간별 위치정보 검색과 시점 위치정보 검색이 가능하다.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.10
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• pp.208-213
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• 2001

High speed milling(HSM) is one of the emerging cutting process having tremendous potential not only in increased metal removal rates but also in improved surface finish, burr free edge, dimensional accuracy and a virtually stress free component after machining. The High efficiency and accuracy in machining of die/mold materials can be obtained in high speed machining, so it is necessary to analytic the mechanism of high speed cutting process : cutting force, acoustic emission signal.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2018.11a
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• pp.237-238
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• 2018

부산항만은 관리하는 범위가 넓고(용호만-부산신항) 노후화 시설이 다수 차지하여 인력만으로 관리하기에 한계가 있다. 이러한 한계를 극복하기 위해서는 새로운 방법이나 기술도입이 필요하다고 판단된다. 따라서 본 연구에서는 부산항만시설 중 인력운영의 사각지대를 대상으로 IoT 기술을 통한 모니터링 시스템 구축을 통하여 보다 넓은 영역의 시설물을 효율적으로 관리할 수 있는 방안을 ${\cdot}{\cdot}$ (중략) ${\cdot}{\cdot}$.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.8
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• pp.1491-1496
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• 2009

This paper presents an digital based input/output interface circuit for controlling and monitoring the Diesel Engine Generator for emergency. In order to monitor and control of the Emergency Diesel Engine Generator, controlling and monitoring circuits need 5 analog input channels, 2 pick-up coil measuring circuits, 10 digital input channels containing Broken Wire Detect function, and 7 relay control signal output channels. This system performs signal processing of input signal taking advantage of simple filter circuit, photo-coupler and comparator circuit at analog input parts, and output signals for main relay is designed acting by double control, so it prevents malfunction completely. And it improves accuracy of speed input signal by applying digital circuit that processes rick-up coil signal.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.28 no.11
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• pp.843-852
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• 2017

Recently, as the WHO IARC has classified radio frequency electromagnetic fields as possibly carcinogenic (group 2B) to humans, there is increasing concern about the health effects of overexposure from electromagnetic fields. Especially, the workers are exposed to higher level of electromagnetic radiation than the general public. As a result, in Europe, the protection guidelines for the worker are developed and the exposure of the worker is strictly controlled. In this paper, the EU directive, standards and guidelines of the EMF exposure for the worker were reviewed, and the exposure assessment of EMF was performed for the arc welding. Based on that, we propose a way to introduce a national policy to protect the workers from EMF exposure in working environment.