• Journal of Astronomy and Space Sciences
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• v.23 no.3
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• pp.227-236
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• 2006

The fractal dimension is a quantitative parameter describing the characteristics of irregular time series. In this study, we use this parameter to analyze the irregular aspects of solar activity and to predict the maximum sunspot number in the following solar cycle by examining time series of the sunspot number. For this, we considered the daily sunspot number since 1850 from SIDC (Solar Influences Data analysis Center) and then estimated cycle variation of the fractal dimension by using Higuchi's method. We examined the relationship between this fractal dimension and the maximum monthly sunspot number in each solar cycle. As a result, we found that there is a strong inverse relationship between the fractal dimension and the maximum monthly sunspot number. By using this relation we predicted the maximum sunspot number in the solar cycle from the fractal dimension of the sunspot numbers during the solar activity increasing phase. The successful prediction is proven by a good correlation (r=0.89) between the observed and predicted maximum sunspot numbers in the solar cycles.

• Journal of the Korea Concrete Institute
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• v.14 no.2
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• pp.171-179
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• 2002

This paper is a part of research series for the verification of the proposed Moon/Lim design equation. An analytical study was performed to examine the relation between the flexural behavior and the unbonded tendon stress of PSC members. The strain compatibility assumption was used in this study since previous studies showed that the stress variations of tendon had a close relation with the member displacements. The proposed equation has been developed with the same assumption of strain compatibility. Therefore the analytical procedure with the strain compatibility assumption was developed to compute the member displacements of previous tests. Then the analytical results were compared with tests results. The comparison showed that the strain compatibility assumption can be properly applicable to the design equation. Based on the analytical results, the relation between the tendon stress and the member flexural behavior at ultimate was examined. A parametric study also carried out with regard to the member displacements. As results, the parameters used for the proposed equation were proven to be proper for the computation of tendon stress.

• Journal of Mushroom
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• v.14 no.1
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• pp.14-20
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• 2016

This study was conducted to establish replacement the corncob used in winter mushroom bottle cultivation. Corncob is unstable quality in moisture content or total nitrogen(T-N) content. Fruit body yields according to the ratio of cassava stem chips mixing were compared. After treatment-1 and treatment-2, fruit body yields increased by 8.8% and 5.4% and raw material cost decreased by 7% and 19%. The results showed that cassava stem chips could replace 33% to 67% of corncob for winter mushroom bottle cultivation.

• Proceedings of the Acoustical Society of Korea Conference
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• autumn
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• pp.121-124
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• 2001

음성 합성기의 합성음의 자연감을 높이기 위해 자연음에 내재하는 정확한 운율 법칙을 구하여 음성합성 시스템에서 이를 구현해 주어야 한다 무제한 어휘 음성합성 시스템의 문-음성 합성기에서 필요한 운율 법칙은 언어학적 정보를 이용해 구하거나, 자연음에서 추출하고 있다 그러나 추출한 운율 법칙이 자연음에 내재하는 모든 운율 법칙을 반영하지 못했거나, 잘못 구현되는 경우에는 합성음의 자연성이 떨어지게 된다. 이런 점을 고려하여 본 논문에서는 한국어 자연음을 분석하여 추출한 운율 정보를 인공 신경망이 학습하도록 하고 훈련을 마친 인공 신경망에 문장을 입력하고, 출력으로 나오는 운율 정보와 자연음의 운율 정보를 비교한 결과 제안한 인공 신경망이 자연음에 내재하고 있는 운율을 학습할 수 있음을 알 수 있었다. 운율의 3대 요소는 피치 , 지속시간, 크기의 변화이다. 제안한 인공 신경망이 한국어 문장의 음소 열을 입력으로 받아들이고, 각 음소의 지속시간에 따른 피치변화와 크기 변화를 출력으로 내보내면 자연음을 분석해 구한 각 음소의 운율 정보인 목표 패턴과 출력 패턴 의 오차를 최소화하도록 인공 신경망의 가중치를 조절할 수 있도록 설계하였다. 지속시간에 따른 각 음소의 피치와 크기 변화를 학습시키기 위해 피치 및 크기 인공 신경망을 구성하였다. 이들 인공 신경망을 훈련시키기 위해 먼저 음소 균형 문장 군을 구축하여야 하고, 이들 언어 자료를 특정 화자가 일정 환경에서 읽고 이를 녹음하여 , 분석하여 구한운율 정보를 운율 데이터베이스로 구축하였다. 문장 내의 각 음소에 대해 지속 시간과 피치 변화 그리고 크기 변화를 구하고, 곡선 적응 방법을 이용하여 각 변화 곡선에 대한 다항식 계수와 초기 값을 구해 운율 데이터베이스를 구축한다. 이 운율 데이터베이스의 일부는 인공 신경망을 훈련시키는데 이용하고, 나머지로 인공 신경망의 성능을 평가하여 인공 신경망이 운율 법칙을 학습할 수 있었다. 언어 자료의 문장 수를 늘리고 발음 횟수를 늘려 운율 데이터베이스를 확장하면 인공 신경망의 성능을 높일 수 있고, 문장 내의 음소의 수를 감안하여 인공 신경망의 입력 단자의 수는 계산량과 초분절 요인을 감안하여 결정해야 할 것이다

• Korean Journal of Food Science and Technology
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• v.23 no.5
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• pp.578-581
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• 1991

The antioxidative effects of three kinds of commercial lecithin in fish oil(EPA 25%, DHA 10%) were investigated through active oxygen method (AOM, hrs. at $97.8^{\circ}C$), Oven test, polymer test by gel chromatography and coloring test. Although there were difference of antioxidative effect among commercial lecithins, antioxidative effects of the lecithins added to the fish oil increased with increasing the concentration of lecithin. Lecithin III(acetone insoluble content 65%) had the greatest antioxidative effect and the addition of 1%, 5 and 10% enhanced the oxidative stability to 310%, 620% and 840%, respectively. The results also showed that the polymerization in presence of 10% lecithin III did not occur up to 10 hours at the AOM condition, and the degree of color(Gardner number) increased as storage time went by and was accerated at high temperature.

• Korean Journal of Plant Taxonomy
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• v.36 no.4
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• pp.309-333
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• 2006

Examined were the vegetative and reproductive characters such as external morphology, anatomy (leaf petiole, blade and stem), pollen and nutlet for the taxonomic revision of Elsholtzia in Korea. The inflorescence of all studied taxa of Elsholtzia in Korea is secund and 0.5-10 cm long. Leaves are ovate or nearly and $0.2-10{\times}0.2-6.0cm$. The shapes of inflorescence and leaves are very useful taxonomic characters. The stomata types are anomocytic and diacytic. The morphology of nutlet is ovoid and pitted in surface pattern of exocarp. All studied taxa are myxocarpy. The pollen grains are of medium size and subprolate in shape, and have typical bi-reticulate exine surface. Four species are recognized for Korean Elsholtzia by the identification key and descriptions in this study.

• Journal of the Institute of Electronics and Information Engineers
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• v.54 no.6
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• pp.72-79
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• 2017

In this paper, we present a new saliency detection algorithm using the mutual information of wavelet subbands. Our method constructs an intermediate saliency map using the power operation and Gaussian blurring for high-frequency wavelet coefficients. After combining three intermediate saliency maps according to the direction of wavelet subband, we find the main directional components using entropy measure. The amount of mutual information of each subband is obtained centering on the subband having the minimum entropy The final saliency map is detected using Minkowski sum based on weights calculated by the mutual information. As a result of the experiment on CAT2000 and ECSSD databases, our method showed good detection results in terms of ROC and AUC with few computation times compared with the conventional methods.

• Archives of Plastic Surgery
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• v.37 no.4
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• pp.346-350
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• 2010

Purpose: Diagnosis of diabetic foot infection is sometimes difficult, since the classical inflammatory signs and leukocytosis may be absent due to the decreased host immune response in diabetics. Therefore inflammatory blood markers, such as white blood cell (WBC) count, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) have been commonly needed to confirm the diagnosis of infection. The purpose of this study is to evaluate the diagnostic usefulness of WBC, ESR and CRP for detection of diabetic foot infection. Methods: Peripheral blood samples were taken from 113 patients with diabetic foot ulcers admitted from June 2007 to April 2009. Diabetic foot infection was diagnosed according to the microbiological culture from soft tissue and bone specimens. Reference values of tests were 4500-11000 /${\mu}L$ for WBC count, 0-20 mm/hr for ESR, and 0-5 mg/L for $CRP^{13,14}$. Sensitivities, specificities, positive and negative predictive values of laboratory tests were calculated and analysed. Receiver-operator characteristic (ROC) curve was also created. Results: There was a significant difference in WBC, ESR, and CRP between infectious group and noninfectious group (p<0.05). The sensitivity of WBC>11,000 /${\mu}L$ ESR > 20 mm/hr, and CRP > 5 mg/L was 30%, 96%, and 84%. The specificity was 86%, 14%, and 50% for WBC, ESR, and CRP, respectively. Positive predictive value was 88%, 78%, and 84%, and negative predictive value was 28%, 50%, and 50% respectively. The areas under the ROC curve for WBC, ESR and CRP were 0.72, 0.75, and 0.78 respectively. Conclusion: Based on the results of this study, we conclude that CRP is more useful method in predicting and diagnosing infection than WBC, ESR in diabetic foot ulcer patients.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2014.10a
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• pp.342-345
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• 2014

Network intrusion detection system based on machine learning methods is quite dependent on the selected features in terms of accuracy and efficiency. Nevertheless, choosing the optimal combination of features from generally used features to detect network intrusion requires extensive computing resources. For instance, the number of possible feature combinations from given n features is $2^n-1$. In this paper, to tackle this problem we propose a optimal feature selection algorithm. Proposed algorithm is based on the local search algorithm, one of representative meta-heuristic algorithm for solving optimization problem. In addition, the accuracy of clusters which obtained using selected feature components and k-means clustering algorithm is adopted to evaluate a feature assembly. In order to estimate the performance of our proposed algorithm, comparing with a method where all features are used on NSL-KDD data set and multi-layer perceptron.

• Phonetics and Speech Sciences
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• v.13 no.4
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• pp.55-66
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• 2021

Proper prosody in reading allows the reader to naturally convey the meaning, which manifests as changes in pitch, loudness, and speech rate. Children with reading disability face difficulty in delivering information due to poor prosody. This study identified the difference in prosodic features between children with reading disabilities and nondisabled children through means of reading tasks. Reading tasks, according to sentence types (short sentences, assumptions/conditions, intentions, relative-clause), were recorded by 15 children studying in the 3rd to 6th grade in elementary school. Children with reading disability had a statistically significant wider range of pitch, slower speech rate, more frequent usage of pauses, longer total pause duration, and steeper pitch slope than nondisabled one in sentence-final and -medial words. Children with reading disability, therefore, exhibited a less natural and expressive reading than nondisabled children. Through this study, the characteristics of prosody observed in children with reading disability were identified and the need for an approach for effective intervention was also suggested.