• The Journal of Korean Institute for Practical Engineering Education
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• v.3 no.1
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• pp.45-50
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• 2011

Despite the highly sophisticated development of finite element analysis, a finite element model for structural dynamic analysis can be inaccurate or even incorrect due to the difficulties of correct modelling, uncertainties on the finite element input data and geometrical oversimplification, while the modal data extracted from measurement are supposed to be correct, even though incomplete. The assumption that the test results represent the true dynamic behaviour of the structure, however, may not be correct because of various measurement errors. The measurement errors are investigated and their effects on estimated frequency response functions(FRFs) are also investigated.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.53 no.10
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• pp.733-740
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• 2004

In this paper, an improved algorithm for the extraction of respiration signal from the electrocardiogram (ECG) is proposed. The whole system consists of two-lead electrocardiogram acquisition (lead Ⅰ and Ⅱ), baseline fluctuation elimination, R-wave detection, adjustment of sudden change in R-wave area using moving average, and optimal lead selection. In order to solve the problem of previous algorithms for the ECG-derived respiration (EDR) signal acquisition, we proposed a method for the optimal lead selection. An optimal EDR signal among the three EDR signals derived from each lead (and arctangent of their ratio) is selected by estimating the instantaneous frequency using the Hilbert transform, and then choosing the signal with minimum variation of the instantaneous frequency. The proposed algorithm was tested on 15 subjects, and we could obtain satisfactory respiration signals that shows high correlation (r>0.9) with the signal acquired from the chest-belt respiration sensor.

• Journal of the Korean Institute of Intelligent Systems
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• v.13 no.1
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• pp.45-50
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• 2003

Recently, robots technique has been developed remarkably. Emotion recognition is necessary to make an intimate robot. This paper shows the simulator and simulation result which recognize or classify emotions by learning pitch pattern. Also, because the pitch is not sufficient for recognizing emotion, we added acoustic elements. For that reason, we analyze the relation between emotion and acoustic elements. The simulator is composed of the DRNN(Dynamic Recurrent Neural Network), Feature extraction. DRNN is a learning algorithm for pitch pattern.

• Journal of the Institute of Electronics Engineers of Korea TE
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• v.39 no.4
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• pp.379-388
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• 2002

In this paper, the real-time algorithm is proposed for automatic detection of the face and facial features. In the face region, we extracted eyes, nose, mouth and so forth. There are two methods to extract them; one is the method of using the location information of them, other is the method of using Gaussian second derivatives filters. This system have high speed and accuracy because the facial feature extraction is processed only by detected face region, not by whole image. There are some kinds of good experimental result for the proposed algorithm; high face detection rate of 95%, high speed of lower than 1sec. the reduction of illumination effect, and the compensation of face tilt.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.29 no.9
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• pp.731-734
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• 2018

Many studies have been conducted on the accurate detection and identification of targets from ground clutter, in order to improve the accuracy rate of land guided weapons. Due to the variety and complicated characteristics of the ground clutter signal compared to the target, an active target identification technique is needed. In this paper, we propose a new algorithm to identify targets and divide them into different types by extracting the unique characteristics of the target through fractal dimension calculation with the characteristics of self-similarity. In the simulation using the algorithm, the probabilities of identifying the tank and truck were 100 % and 98.89 %, respectively, and the type of the target could be identified with a probability of 98 % or more.

• The Journal of Internal Korean Medicine
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• v.38 no.4
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• pp.409-418
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• 2017

In Korea, Rhus verniciflua Stokes is used to purge hardness, alleviate blood stasis, and treat cancer. However, the mechanisms of related anti-cancer activity are not fully understood in human cancer cells. This study investigated the anti-cancer effects and mechanisms of Rhus verniciflua Stokes on MDA-MB-231 human breast cancer cells and found that treatment with a Rhus verniciflua Stokes extract resulted in time- and concentration-responses that indicated growth inhibition of breast cancer cells by induced apoptosis. This was followed by a decrease in mitochondrial membrane potential; the activation of caspase-3, -8, and -9; and the up-regulation of tBid. Caspase-dependent apoptosis was induced through the inhibition of phosphatidylinositol 3-kinase (PI3K) and the Akt signaling pathway. This study provides evidence that Rhus verniciflua Stokes might be useful for the treatment of breast cancer.

• Korean Journal of Pharmacognosy
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• v.39 no.3
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• pp.228-232
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• 2008

Antidiabetic effects of an aqueous and solvent extract prepared from the root, stem and fruit parts of Acanthopanax senticosus, were investigated in experimental Streptozotocin (STZ)-induced diabetic rats model. The n-butanol and water extracts of A. senticosus were orally administrated once a day for 6 days. The n-butanol extracts of fruit (FB) showed highest efficiency than other groups (water extracts of stem, root and fruit; butanol extracts of stem, root) on serum glucose values in the STZ-induced diabetic rats. We have studied gene expression of glucose transporter genes in C2C12 skeletal muscle cell line during differentiation treated by the n-butanol and water extracts of A. senticosus, SW, RW, FW, SB, RB and FB. The GLUT4 gene was high expressed by FB treatment. These findings suggest that FB of A. senticosus have GLUT4 gene expression activity for glucose homeostasis and may have beneficial effects on blood glucose lowering in the diabetic patients.

• Proceedings of the Acoustical Society of Korea Conference
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• spring
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• pp.61-64
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• 1999

기존의 CELP 보코더에서, 무성음에 대한 별도의 처리 없이 유성음과 동일하게 처리하였다. 유성음과 무성음은 발성모델측면에서 임펄스열과 랜덤 잡음으로 각각 다름에 도 불구하고 동일하게 처리함으로써 합성음에서 음질의 저하 및 계산량과 전송률 측면에서 손실을 가져왔다. 또, U/V(Unvoiced /voiced) 분류기를 사용하는 경우에는 U/V 분류기의 성능에 따라 합성음의 음질저하의 정도의 차이가 심하다. 본 논문에서는 에러율과 전처리 계산량을 쳐소로 할 수 있는 U/V 분류기를 사용하여 CELP 보코더에서 전송률을 감소시키는 방법을 제안한다. CELP 보코더에서는 스펙트럼 정보를 LPC 파라미터로 추출한 후 다시 전송형 파라미터인 LSP(Line Spectrum Frequency)로 변환한다 새로운 린/V 분류기는 이 LSP 파라미터를 이용한다. LSP 파라미터의 주파수영역 분포도와 간격정보를 이용하여 U/V를 결정하게 된다 제안한 방법을 5.3kbps ACELP에 적용하여 성능 평가를 실시하였다 실험결과 음질의 저하 없이 $5.6\%$ (280bps)의 전송률을 감소할 수 있었다.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.1374-1375
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• 2008

본 논문은 3상 일괄형 GIS의 부분방전 진단을 위해 새롭게 개발한 진단 알고리즘에 관한 것이다. 진단 알고리즘 개발을 위해, 먼저 실시간 부분방전 데이터를 행벡터 및 열벡터로 구성하고 각각의 벡터에서 통계 특징량 및 질감 특징량을 추출하였다. 다음으로 이들 특징량을 GA-NN(Genetic Algorithm - Neural Network) 학습에 적용하여 진단 알고리즘을 구성하였다. 또한 진단 알고리즘의 위상독립성은 부분방전 신호의 위상변화에 관계없이 진단결과가 일치하는 것을 확인함으로써 검증하였다. 개발한 진단알고리즘의 실증 평가를 위해, 부분방전이 발생되고 있는 국내 3상 일괄형 GIS 변전소에 적용하였다. 적용 결과, 위상에 관계없이 부분방전 발생원을 정확히 진단함을 확인하였고, 이를 통해 개발 알고리즘의 우수성을 입증하였다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.22 no.6
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• pp.910-915
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• 2018

The precise time, which is an essential element of the Global Navigation Satellite System (GNSS), such as US GPS, GLONASS in Russia, Galileo in Europe, and Beidou in China, is an important foundation for various economic activities around the world. Communication systems, power grids, IoT, Cloud computing and financial networks operate based on the precise time not only for the operating principles, but also for the synchronization and operational efficiency between tasks. In this paper, we introduce the Atomium software for the first time in South Korea. Atomium was developed by ORB in Belgium to calculate the clock error(clock solution) with GNSS signal observation data based on PPP method. The observation data is provided by Korea Research Institute of Standards and Science(KRISS). The results of MJD57106 with Atomium software are presented.