• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 C
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• pp.1655-1657
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• 1994

To measure treeing, visual measurement with an optical microscope has been used to explain breakdown mechanism by treeing in materials. The conventional direct visual method of tree deterioration observation is difficult to measure in short time processing, and impossible to analyze the deteriorated area by treeing, direction of tree growth, tree patterns etc. In this paper, we have developed a tree-measuring system using image processing for the tree growth, the area of deterioration, and other progresses of treeing. As experimental result, image processing is an effective alternative to direct visual observation method.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 G
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• pp.2445-2447
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• 1998

For increasing the quality of SCADA system, the application of image information is demanded from typical SCADA system based on data information. Until now, the remote control and monitoring systems combine data information but now gradually have trends to combine voice, data and image information. So multimedia technology is applied to realize new SCADA system. Depends on these requires, we apply new concepts of communication network and multimedia technology to the SCADA system for electric facility. In this paper, we aim at developing multi media supervisory control and data acquisition system based on data and image information, which used electric power system and security system.

• Journal of Electrical Engineering and information Science
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• 제1권2호
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• pp.67-76
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• 1996

In the present paper we propose two new improved iterative restoration algorithms. One is to accelerate convergence of the steepest descent method using the improved search directions, while the other accelerates convergence by using preconditioners. It is also shown that the proposed preconditioned algorithm can accelerate iteration-adaptive iterative image restoration algorithm. The preconditioner in the proposed algorithm can be implemented by using the FIR filter structure, so it can be applied to practical application with manageable amount of computation. Experimental results of the proposed methods show good perfomance improvement in the sense of both convergence speed and quality of the restored image. Although the proposed methods cannot be directly included in spatially-adaptive restoration, they can be used as pre-processing for iteration-adaptive algorithms.

• 한국방사선학회논문지
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• 제10권4호
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• pp.247-253
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• 2016

초음파 장비는 여러 질환을 진단하는 장비로서 널리 사용되고 있으나, 초음파영상 품질의 평가방법에서는 정량적 표준이 없는 실정이다. 따라서 본 연구에서는 ATS-539 다목적 팬텀 내 8 mm 표적의 파라미터로서 주파수, Dynamic range, 초점수를 변화하여 예민도의 SNR과 영상의 히스토그램을 분석하고 왜곡도를 측정하여 표적별 적합한 주파수 및 파라미터를 도출하여 초음파영상의 병변 진단율을 향상 하고자 한다. 실험재료는 초음파 장비, ATS-539 다목적 팬텀을 사용하며, 실험방법은 영상 평가 팬텀의 8 mm를 주파수(2, 3, 4 MHz, 하모닉 3, 4, 4.5 MHz), Dynamic range(58, 68, 78, 88, 98), Focus(2, 4, 6개)를 변화시키면서 85장의 영상을 획득한다. 8 mm 영상의 예민도를 Image J 프로그램에서 각 표적별 SNR을 측정하고, 왜곡도는 신호의 히스토그램에서 백그라운드 값을 뺄셈하여 측정한다. 측정 결과 값에서 상위 40% 결과에서 파라미터 변화에 따라 예민도의 SNR, 왜곡도의 변화양상의 데이터 값을 산출하여 초음파 장비에서 적절한 영상의 품질을 나타내는 파라미터를 도출하였다. 결과는 초점수가 증가하면 SNR이 높고 왜곡도가 감소하며, 주파수 4 MHz에서 SNR값이 높고 왜곡도가 감소하였다. 그리고 Dynamic range 88, 98에서 최적의 영상을 나타내었으며, 실험 결과값을 기초로 초음파영상의 품질을 평가한다면 보다 정확한 초음파 진단이 가능할 것으로 사료된다.

• 전자통신동향분석
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• 제35권6호
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• pp.37-47
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• 2020

Today, the volume of international trade by airplanes and ships is rapidly increasing, and the volume of trade over land is expected to increase as inter-Korean relations change. In customs processes, humans inspect using the naked eye; therefore, computer vision technology can be used to assist customs inspectors responsible for X-ray security screening. In particular, because of recent advances in deep learning technology, algorithms for image understanding and object detection performance are improving, and studies on their application to X-ray screening have been published. This manuscript describes trends in artificial intelligence X-ray image-reading technology to detect prohibited items. X-ray inspection AI technology is similar to the Sphinx, which was the guardian of the pyramids in ancient Egyptian mythology.

• 전자통신동향분석
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• 제33권4호
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• pp.43-53
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• 2018

As face recognition (FR) has been well studied over the past decades, FR technology has been applied to many real-world applications such as surveillance and biometric systems. However, in the real-world scenarios, FR performances have been known to be significantly degraded owing to variations in face images, such as the pose, illumination, and low-resolution. Recently, visual intelligence technology has been rapidly growing owing to advances in deep learning, which has also improved the FR performance. Furthermore, the FR performance based on deep learning has been reported to surpass the performance level of human perception. In this article, we discuss deep-learning based high-performance FR technologies in terms of representative deep-learning based FR architectures and recent FR algorithms robust to face image variations (i.e., pose-robust FR, illumination-robust FR, and video FR). In addition, we investigate big face image datasets widely adopted for performance evaluations of the most recent deep-learning based FR algorithms.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2005년도 후기학술대회논문집
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• pp.118-119
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• 2005

Recently, fire extinguishing systems based on water mists have been attracting public attentions in marine engineering. Performance of the fire extinguishing systems is influenced by the size and distribution of spayed water mists. Droplet analyzing method based on image processing technique for measuring droplet size and distribution has been developed. The morphological method based on partial curvature information of pre-processed images was adopted for recognition and separation of overlapped particles. Tested results show that the present method may be reliable for the analysis of the size and distribution of droplets produced by water mist spay flow.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 추계학술대회 논문집
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• pp.565-566
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• 2006

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집B
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• pp.686-691
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• 2000

Animation technique from the PIV database is particularly emphasized to give macroscopic and Quantitative description of complex flow fields. As an example, an experimental study was carried out investigate the fundamental (low characteristics of the freezer with the domestic refrigerator. Optimized cross correlation identification to obtain velocity vectors is implemented by direct calculation of correlation coefficients. Image intensifier CCD camera to cope with illumination problem is arranged for the accurate PIV measurement of large flow field. As a results, continuous pictures of the spatial distribution of the instantaneous and time-mean velocity distribution are displayed in real-time sense.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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• pp.505-508
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• 2001

Currently there is much interested in removing latent charge that is caused to latent image effect and blurring of obtained image as well as reduction of x-ray conversion efficiency in digital radiography system. To remove latent charge a-Se film is irradiated by light with 3500 lux using halogen lamp and optical fiber. We measured dark current and photosensitivity to analyze removing effect of latent charge, then compared with and without light erasing method. The reduction of measured signal due to latent charge effect was 32.5 %, and the removal effect of latent charge by using light erase method was its 95.5 %.