• 생약학회지
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• 제19권3호
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• pp.153-169
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• 1988

The combined use of the J-modulated selective INEPT and CSCM 1DNMR techniques is described for the structure elucidation of several new classes of compound including prionitin, the loureirins and larreantin, and for the regiosubstitution of the furanonaphthoquinones. Spectroscopic studies on the conformation of the cytotoxic agent savinin are also described, together with the NMR assignments and preliminary biosynthetic experiments on the antitumor antibiotic staurosporine.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2003년도 가을 학술발표회 논문집
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• pp.123-129
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• 2003

Drift design using resizing techniques can be a very practical method in drift design of high-rise buildings since it cannot require sensitivity analysis and structural re-analysis. Resizing techniques has used the cross sectional areas as design variable and supposed that displacement participation factors are inversely proportional to structural weights. Efficiency of resizing techniques based on displacement participation factors may depend on proper selection of sectional properties as design variables. In this study, two different drift design methods with the different sectional properties as design variables are presented and applied to a 20-story structure.

• 정보보호학회논문지
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• 제32권2호
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• pp.181-192
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• 2022

신종 악성코드의 등장은 기존 시그니처 기반의 악성코드 탐지 기법들을 무력화시키며 여러 분석 방지 보호 기법들을 활용하여 분석가들의 분석을 어렵게 하고 있다. 시그니처 기반의 기존 연구는 악성코드 제작자가 쉽게 우회할 수 있는 한계점을 지닌다. 따라서 본 연구에서는 악성코드 자체의 특성이 아닌, 악성코드에 적용될 수 있는 패커의 특성을 활용하여, 단시간 내에 악성코드에 적용된 패커의 분석 방지 보호 기법을 탐지하고 분류해낼 수 있는 머신러닝 모델을 구축하고자 한다. 본 연구에서는 패커의 분석 방지 보호 기법을 적용한 악성코드 바이너리를 대상으로 n-gram opcode를 추출하여 TF-IDF를 활용함으로써 피처(feature)를 추출하고 이를 통해 각 분석 방지 보호 기법을 탐지하고 분류해내는 머신러닝 모델 구축 방법을 제안한다. 본 연구에서는 실제 악성코드를 대상으로 악성코드 패킹에 많이 사용되는 상용 패커인 Themida와 VMProtect로 각각 분석 방지 보호 기법을 적용시켜 데이터셋을 구축한 뒤, 6개의 머신러닝 모델로 실험을 진행하였고, Themida에 대해서는 81.25%의 정확도를, VMProtect에 대해서는 95.65%의 정확도를 보여주는 최적의 모델을 구축하였다.

• 정보화연구
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• 제11권1호
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• pp.25-32
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• 2014

웹 마이닝은 사용자의 웹 이용 분석을 위해 웹에서 발생한 데이터를 대상으로 유용한 패턴을 찾아내는 기법이다. 하지만 기존의 웹 마이닝은 웹 로그의 연속적인 특성을 충분히 반영하여 분석하지 못하였다. 이를 보완하기 위하여 본 연구에서는 프로세스 마이닝을 활용하여 프로세스 모델에 의한 순차적인 관계에 따른 웹 접속 로그를 분석하는 프레임워크를 제시한다. 프로세스 모델에 기반한 웹 로그 분석은 웹 페이지들을 이동한 사용자들의 행위를 이해하고 문제점과 개선방안을 도출하는 데 유용하게 사용될 수 있다. 본 연구에서는 제안한 방법론을 이용하여 대학정보시스템의 웹 로그를 분석하여 적용 가능성과 그 분석 결과를 제시하였다.

• 한국유체기계학회 논문집
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• 제15권2호
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• pp.5-11
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• 2012

In this paper, the heat transfer coefficient measurement techniques using TSP(temperature sensitive paint) were introduced and the results of a comparative study on the heat transfer coefficient measurement by steady state and transient TSP techniques were discussed. The distributions of heat transfer coefficient by a single $60^{\circ}$ inclined impingement jet on a flat surface were measured by both techniques. Tested Reynolds number based on the jet diameter (d) was 30,000 and the distance between jet exit and target plate (L) was fixed at 10d. Results showed that the measured Nusselt number by both techniques indicated significant difference except near the center of impingement jet. Also, the heat transfer coefficients measured by the transient TSP technique were affected by the reference temperature of the jet. Based on the measured data, characteristics of both TSP techniques were analyzed and suggestions for applying them were also given.

• Nuclear Engineering and Technology
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• 제53권3호
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• pp.942-948
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• 2021

The aim of this work is to help inform the decision for choosing a convenient material for the PGAA (Prompt Gamma Activation Analysis) collimator plug to be installed at the tangential channel of the Moroccan Triga Mark II Research Reactor. Two families of materials are usually used for collimator construction: a mixture of high-density polyethylene (HDPE) with boron, which is commonly used to moderate and absorb neutrons, and heavy materials, either for gamma absorption or for fast neutron absorption. An investigation of two different collimator designs was performed using N-Particle Monte Carlo MCNP6.2 code with the ENDF/B-VII.1 and MCLIP84 libraries. For each design, carbon steel and lead materials were used separately as collimator heavy materials. The performed study focused on both the impact on neutron beam quality and the neutron-gamma background at the exit of the collimator beam tube. An analysis and assessment of the principal findings is presented in this paper, as well as recommendations.

• Asia pacific journal of information systems
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• 제32권4호
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• pp.770-802
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• 2022

With the development of deep learning techniques, text mining is producing breakthrough performance improvements, promising future applications, and practical use cases across many fields. Likewise, even though several attempts have been made in the field of financial information, few cases apply the current technological trends. Recently, companies and government agencies have attempted to conduct research and apply text mining in the field of financial information. First, in this study, we investigate various works using text mining to show what studies have been conducted in the financial sector. Second, to broaden the view of financial application, we provide a description of several text mining techniques that can be used in the field of financial information and summarize various paradigms in which these technologies can be applied. Third, we also provide practical cases for applying the latest text mining techniques in the field of financial information to provide more tangible guidance for those who will use text mining techniques in finance. Lastly, we propose potential future research topics in the field of financial information and present the research methods and utilization plans. This study can motivate researchers studying financial issues to use text mining techniques to gain new insights and improve their work from the rich information hidden in text data.

• 보존과학연구
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• 통권31호
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• pp.141-154
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• 2010

Many bronze artifacts have been excavated and preserved through conservation treatments in Korea but the analysis on artifacts was regarded as destruction of artifacts from the academic world of archaeology, Therefore, it is not so available to perform research on production techniques and provenances by with qualified analysis. Accordingly, there were only a few study cases about quality properties and production techniques But recently gradual change started to appear from the awareness of the need for the scientific approach to excavated artifacts. While Korean ancestors already had applied the different alloying ratios according to the use and shape of bronze artifacts, the analysis and study have been restrictedly performed. As a result, there was only a few analysis cases on a small minority of artifacts because they are the ancient relics, which made it hard to understand the bronze artifacts more deeply. This study researched into components rate, production techniques and hardness of bronze weapons such as a bronze sword and compared their alloying ratios with those of Chinese old records (周禮考工記, 金之六齊).

• 대한음성학회지:말소리
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• 제65호
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• pp.153-168
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• 2008

We propose a new method to apply shape analysis techniques to a computational auditory scene analysis (CASA)-based speech separation system. The conventional CASA-based speech separation system extracts speech signals from a mixture of speech and noise signals. In the proposed method, we complement the missing speech signals by applying the shape analysis techniques such as labelling and distance function. In the speech separation experiment, the proposed method improves signal-to-noise ratio by 6.6 dB. When the proposed method is used as a front-end of speech recognizers, it improves recognition accuracy by 22% for the speech-shaped stationary noise condition and 7.2% for the two-talker noise condition at the target-to-masker ratio than or equal to -3 dB.

• 한국IT서비스학회지
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• 제18권2호
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• pp.123-141
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• 2019

The goal of this study is to review the major research trend on the convergence studies of AI and healthcare technologies. For the study, 15,260 English articles on AI and healthcare related topics were collected from Scopus for 55 years from 1963, and text mining techniques were conducted. As a result, seven key research topics were defined : "AI for Clinical Decision Support System (CDSS)", "AI for Medical Image", "Internet of Healthcare Things (IoHT)", "Big Data Analytics in Healthcare", "Medical Robotics", "Blockchain in Healthcare", and "Evidence Based Medicine (EBM)". The result of this study can be utilized to set up and develop the appropriate healthcare R&D strategies for the researchers and government. In this study, text mining techniques such as Text Analysis, Frequency Analysis, Topic Modeling on LDA (Latent Dirichlet Allocation), Word Cloud, and Ego Network Analysis were conducted.