• Journal of Plant Biology
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• v.20 no.4
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• pp.160-166
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• 1977

미국 North Carolina주의 담수산 녹조식물 Mesotaeniaceae를 구명하기 위하여 1962년부터 1969년 사이에 200여개소에서 채집한 재료를 조사한 결과, 6속 16종 7변종 1아종이 동정되었다. 그중 3종 1변종은 North Calrolina주의 말기록종 식물이었다.

• Journal of Internet Computing and Services
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• v.22 no.2
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• pp.1-9
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• 2021

Traditionally, most malicious codes have been analyzed using feature information extracted by domain experts. However, this feature-based analysis method depends on the analyst's capabilities and has limitations in detecting variant malicious codes that have modified existing malicious codes. In this study, we propose a ResNet-Variational AutoEncder-based variant malware classification method that can classify a family of variant malware without domain expert intervention. The Variational AutoEncoder network has the characteristics of creating new data within a normal distribution and understanding the characteristics of the data well in the learning process of training data provided as input values. In this study, important features of malicious code could be extracted by extracting latent variables in the learning process of Variational AutoEncoder. In addition, transfer learning was performed to better learn the characteristics of the training data and increase the efficiency of learning. The learning parameters of the ResNet-152 model pre-trained with the ImageNet Dataset were transferred to the learning parameters of the Encoder Network. The ResNet-Variational AutoEncoder that performed transfer learning showed higher performance than the existing Variational AutoEncoder and provided learning efficiency. Meanwhile, an ensemble model, Stacking Classifier, was used as a method for classifying variant malicious codes. As a result of learning the Stacking Classifier based on the characteristic data of the variant malware extracted by the Encoder Network of the ResNet-VAE model, an accuracy of 98.66% and an F1-Score of 98.68 were obtained.

• Journal of KIISE
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• v.43 no.3
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• pp.289-295
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• 2016

Malware authors spread malware variants in order to evade detection. It's hard to detect malware variants using static analysis. Therefore dynamic analysis based on API call information is necessary. In this paper, we proposed a malware family recommendation method to assist malware analysts in classifying malware variants. Our proposed method extract API call information of malware families by dynamic analysis. Then the multiple sequence alignment technique was applied to the extracted API call information. A signature of each family was extracted from the alignment results. By the similarity of the extracted signatures, our proposed method recommends three family candidates for unknown malware. We also measured the accuracy of our proposed method in an experiment using real malware samples.

• Convergence Security Journal
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• v.10 no.3
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• pp.51-60
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• 2010

The expansion of internet technology has made convenience. On the one hand various malicious code is produced. The number of malicious codes occurrence has dramadically increasing, and new or variant malicious code circulation very serious, So it is time to require analysis about malicious code. About malicious code require set criteria for judgment, malicious code taxonomy using Algorithm of weakness difficult to new or variant malicious code taxonomy but already discovered malicious code taxonomy is effective. Therefore this paper of object is various malicious code analysis besides new or variant malicious code type or form deduction using visualization of strong. Thus this paper proposes a malicious code analysis and grouping method using visualization.

• Korean Journal of Environment and Ecology
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• v.12 no.4
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• pp.301-316
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• 1999

The flora of the Hallyo-Haesang National Park were surveyed from May to September, 1998. The flora of this park were listed as 117 families, 296 genus, 373 species, 53 varieties, 7 forms and 3 hybrid in the Namhae, 73 families, 129 genus, 153 species, 16 varieties and 2 forms in Karasan(Mountain), 97 families, 280 genus, 475 species, 53 varieties, 5 forms and 1 hybrid in the Tongyong. Construction of road, recreational facilities and ornamental farms were considered as the major causes of destruction of vegetation conservational measures must be applied urgently to conserve the distinct vegetation and flora of this areas.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.8 no.4
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• pp.242-244
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• 1975

Taxonomical evaluation of P. nuntia var. vallata and P. nuntia var. brevicirris Grube was checked. On the basis of the number of paragnaths and its arrangement pattern it is suggested that these two varieties are no longer valid, and they are synonym of Perinereis nuntia(Savigny, 1818).

• Journal of Convergence for Information Technology
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• v.11 no.11
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• pp.137-142
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• 2021

Although the internet has gained many conveniences and benefits, it is causing economic and social damage to users due to intelligent malware. Most of the signature-based anti-virus programs are used to detect and defend this, but it is insufficient to prevent malware variants becoming more intelligent. Therefore, we proposes a model that detects and defends the intelligent malware that is pouring out in the paper. The proposed model learns by imaging the characteristics of malware based on deeplearning, and detects newly detected malware variants using the learned model. It was shown that the proposed model detects not only the existing malware but also most of the variants that transform the existing malware.

• Proceedings of the Korean Society of Computer Information Conference
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• 2023.01a
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• pp.103-106
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• 2023

코로나 팬데믹 사태로 인해 업무환경이 재택근무를 하는 환경으로 바뀌고 악성코드의 변종 또한 빠르게 발전하고 있다. 악성코드를 분석하고 백신 프로그램을 만들면 새로운 변종 악성코드가 생기고 변종에 대한 백신프로그램이 만들어 질 때까지 변종된 악성코드는 사용자에게 위협이 된다. 본 연구에서는 머신러닝 알고리즘을 사용하여 악성파일 여부를 예측하는 방법을 제시하였다. 일반적인 악성코드의 구조를 갖는 Portable Executable 구조 파일을 파이썬의 LIEF 라이브러리를 사용하여 Certificate, Imports, Opcode 등 3가지 feature에 대해 정적분석을 하였다. 학습 데이터로는 정상파일 320개와 악성파일 530개를 사용하였다. Certificate는 hasSignature(디지털 서명정보), isValidcertificate(디지털 서명의 유효성), isNotExpired(인증서의 유효성)의 feature set을 사용하고, Imports는 Import Address Table의 function 빈도수를 비교하여 feature set을 구축하였다. Opcode는 tri-gram으로 추출하여 빈도수를 비교하여 feature set을 구축하였다. 테스트 데이터로는 정상파일 360개 악성파일 610개를 사용하였으며 Feature set을 사용하여 random forest, decision tree, bagging, adaboost 등 4가지 머신러닝 알고리즘을 대상으로 성능을 비교하였고, bagging 알고리즘에서 약 0.98의 정확도를 보였다.

• Korean Journal of Environmental Biology
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• v.20 no.4
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• pp.325-338
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• 2002

The distribution and standing crop of phytoplankton were investigated at 12 stations of Songjiho, Ssangho, Maeho and Hyangho as of four lagoons in the east coast from May to November, 2001. It turned out to be total of 164 taxa, and classified as four phylums, four classes, 14 orders, 20 families, 59 genera, 139 species, 22 varieties, two forms and 1 unidentified species by Engler's classification system. Among 104 taxa, 16 taxa including Oscillatoria chlorina were identified as indicators of water pollution and only Cocconeis placentula was the indicator of the clean water. Standing crops of all stations investigated appeared to be relatively high values. Based on the present study upon the distribution and standing crop of phytoplankton, it is regarded as the state of the eutrophication in Songjiho, Ssangho, Maeho and Hyangho as of four lagoons in the east coast.

• Journal of the Speleological Society of Korea
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• no.90
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• pp.9-15
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• 2009

The pisolite of the limstone caverns in korea is one of the varieties of speleology. the main component of the pisolite is calcite, butpisolite often contains quartz and ilite too. the mechanism of encrusting is complicated,but the main process is the accretion which is supposed to take place as fast as 2mmper century.