• Journal of Institute of Control, Robotics and Systems
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• v.20 no.4
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• pp.402-407
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• 2014

In this paper, residual sway control of objects that are moved underwater is investigated. The fuel transfer system in a nuclear power plant transfers the nuclear fuel rods underwater. The research on the dynamics of the loads transferred in different mediums (water and air) and their control methods have not been fully developed yet. The attenuation characteristics of the fuel transfer system have been studied to minimize its residual vibration by considering the effects of hydrodynamic forces acting on the fuel rod. First, a mathematical model is derived for the underwater fuel transfer system, and then experiments have been conducted to study the dynamic behavior of the rod while it travels underwater. Lastly, the residual vibration at the end point is minimized using the input shaping technique.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.11
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• pp.1907-1916
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• 2003

During decades, there has been much progress in understanding of the inelastic behavior of the materials and numerous inelastic constitutive equations have been developed. The complexity of these constitutive equations generally requires a stable and accurate numerical method. To obtain the increment of state variable, its evolution laws are linearized by several approximation methods, such as general midpoint rule(GMR) or general trapezoidal rule(GTR). In this investigation, semi-implicit integration schemes using GTR and GMR were developed and implemented into ABAQUS by means of UMAT subroutine. The comparison of integration schemes was conducted on the simple tension case, and simple shear case and nonproportional loading case. The fully implicit integration(FI) was the most stable but amplified the truncation error when the nonlinearity of state variable is strong. The semi-implicit integration using GTR gave the most accurate results at tension and shear problem. The numerical solutions with refined time increment were always placed between results of GTR and those of FI. GTR integration with adjusting midpoint parameter can be recommended as the best integration method for viscoplastic equation considering nonlinear kinematic hardening.

• Journal of the Korean Society of Costume
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• v.22
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• pp.85-96
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• 1994

The purpose of this research is to find out the role of shaman's costume in Yakut Yukachir Goldi. The results are as follows: 1. Yakut shaman's costumes are decorated by their worship symbols made from metals-wild ducks crucian carps diving beetles and fishes. They believe that these costumes help shamans to travel the heaven underwater or underground systems to collect wanted infor-mation transforming them into the shape of decorated animals. 2. Yukachir shaman's costumes are decorated by symbolized cross medals in the shape of birds and human designed backbone which give shamans much power and many different kinds of medals and tassels representing all sorts and conditions of shaman's power. They consider their cstumes as feather and believe they give them new power and make them to fly anywhere they want. 3. Goldi shaman's costumes have paintings of animal guradians-leopards tigers bears birds snakes lizards and so on. Birds represents freedom of the spirit and eternity. snakes represents rebirth and immorality and lizards represents the trees of underground the earth and the lifetrees of the heaven. Shamans ascend through th holy tree to th heaven and to the world of underground in a comatose condition. Shaman costume itself plays the role of the spiritual safeguard. Wearing their costume shaman get all animal's supernatural authority and power. This makes the shaman to contact with the spirit and to travel the heaven and the under-ground world.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.392-392
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• 2009

결정질 실리콘 태양전지의 모듈화에는 일반적으로 저철분 강화유리를 사용하고 있으며, 이 경우 모듈화를 위해서는 3-5mm 두께의 강화유리를 EVA film을 사용하여 유리와 solar cell을 접착하는 방법을 사용하고 있다. 본 연구에서는 0.7mm 두께의 강화 유리를 사용하고, EVA film을 사용하지 않는 방법으로 초경량의 모듈을 제작하고, 그 특성을 비교하였다. 그결과 박판강화유리를 이용한 경량 실리콘 태양전지의 모듈화의 가장 큰 문제점으로는 강화유리의 두께가 아주 얇기 때문에 발생하는 module의 bending 현상에 의한 silicon cell의 파괴가 일어나는 경우가 있었으며 이를 위한 bending 방지기술의 개발이 요구되는 것으로 나타났다. 개선효과로는 솔라셀 모듈의 에너지변환효율은 동일한 솔라셀을 사용하여 일반 3mm 급의 저철분강화유리로 제작한 모듈에 비해서 약 20% 개선효과가 있었으며, 경량화에는 Al계 금속 지지대를 제외한 모듈만을 비교하여 무게의 감량을 비교한 결과 70%이상의 감량 효과를 나타내는 것으로 나타났다. 상기 결과로부터 본 연구를 통한 개발품은 BIPV형 solar cell module로 이용가치가 기대된다.

• Journal of Life Science
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• v.10 no.4
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• pp.422-430
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• 2000

In order to search for the effects of Shine-Dalgarno (SD) sequence and nucleotide sequence of spacer region (SD-ATG) on bGH expression, oligonucleotides containing random SD sequences and a spacer region were chemically synthesized. The distance between SD region and initiation codon (ATG) was fixed to 9 nucleotides in length. The expression vectors have been constructed using pT7-1 vector containing a T7 promoter. Positive clones were screened with colony hybridization and named pT7A or pT7B plasmid series. The selected clones were confirmed by DNA sequencing and finally, 19 clones having various SD combinations were obtained. When bovine growth hormone was induced by IPTG in E. coli BL21(DE3), all cells harboring these plasmids produced a detectable level of bGH in western blot analysis. However, various SD sequences did not affect on bGH expression, indicating that the sequences of SD and the spacer region did not sufficiently destabilize mRNA secondary structure of bGH gene. Therefore, these results indicate that the disruption of mRNA secondary structure might be a major factor for regulating bGH expression in the translational initiation process.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.15 no.2
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• pp.31-39
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• 2019

Cracked component analysis is needed for structural integrity analysis under seismic loading. Under large amplitude cyclic loading conditions, the change in material properties can be complex, depending on the magnitude of plastic strain. Therefore the cracked component analysis under cyclic loading should consider appropriate cyclic hardening model. This study introduces a procedure for determining an appropriate cyclic hardening model for cracked component analysis. The test material was nuclear-grade TP316 stainless steel. The material cyclic hardening was simulated using the Chaboche combined hardening model. The kinematic hardening model was determined from standard tensile test to cover the high and wide strain range. The isotropic hardening model was determined by simulating C(T) test under cyclic loading using ABAQUS debonding analysis. The suitability of the material hardening model was verified by comparing load-displacement curves of cyclic C(T) tests under different load ratios.

• Journal of Information Technology Services
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• v.16 no.4
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• pp.149-160
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• 2017

Sentiment analysis is the process of determining whether a piece of document, text or conversation is positive, negative, neural or other emotion. Sentiment analysis has been applied for several real-world applications, such as chatbot. In the last five years, the practical use of the chatbot has been prevailing in many field of industry. In the chatbot applications, to recognize the user emotion, sentiment analysis must be performed in advance in order to understand the intent of speakers. The specific emotion is more than describing positive or negative sentences. In light of this context, we propose deep learning models for conducting multi-class sentiment analysis for identifying speaker's emotion which is categorized to be joy, fear, guilt, sad, shame, disgust, and anger. Thus, we develop convolutional neural network (CNN), long short term memory (LSTM), and multi-layer neural network models, as deep neural networks models, for detecting emotion in a sentence. In addition, word embedding process was also applied in our research. In our experiments, we have found that long short term memory (LSTM) model performs best compared to convolutional neural networks and multi-layer neural networks. Moreover, we also show the practical applicability of the deep learning models to the sentiment analysis for chatbot.

• Proceedings of the Korean Information Science Society Conference
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• 2004.04b
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• pp.151-153
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• 2004

비즈니스 인텔리전스는 정보를 저장하고 분석하여 부가가치를 창출해 내는 기술로써 무한경쟁시대에서 기업이 경영환경 추세를 파악하고 경영전략을 세우는데 필수적인 도구이다. 비즈니스 인텔리전스 핵심기술로는 정보를 분석하기 쉬운 형태로 저장하는 데이터웨어하우징 기술과, 정보를 다차원적으로 분석하는 OLAP 기술, 그리고 데이터에 숨겨진 패턴과 관계를 찾아내는 데이터마이닝 기술이 포함되며, 이들 각각을 위한 소프트웨어 제품들은 개발되어 널리 사용되고 있다. 그러나 기업이 요구하는 분석결과를 적시에 제공하기 위해서는 이들을 통합한 개발 프레임워크가 필요하며, 본 연구팀은 그러한 프레임워크 개발 프로젝트(Chamois Project)에 참여하고 있다. 이 프레임워크에는 유사한 기능을 제공하는 여러 종류의 소프트웨어 제품들이 포함되어 있어서, 공통의 응용 프로그래밍 인터페이스(API)를 제공하는 것이 필요하다. 본 연구에서는 특히 다양한 OLAP 제품들을 수월하게 사용할 수 있도록 공통 OLAP API를 개발하였고, 이를 소개하고자 한다. 이와 같이 통합 환경에서 다양한 OLAP 제품들을 지원할 수 있다는 것은 OLAP 제품들의 선택의 폭을 넓히고 응용 프로그램의 코드를 수정하지 않아도 보다 나은 기능을 갖는 OLAP 제품으로의 업그레이드가 쉽게 이루어진다는 장점을 갖는다.

• Elastomers and Composites
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• v.40 no.2
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• pp.119-127
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• 2005

Material characteristics and lifetime evaluation are very important in design procedure to assure the safety and reliability of the rubber components. In this paper, the material test and accelerated heat aging test were carried out to predict the useful life of NBR and EPDM rubber mount for a compression motor which is used in a refrigerator. In order to investigate the effects of heat-aging on the material properties, crosslink density, modulus at 100% strain, stress-strain curves were obtained from uniaxial and equi-biaxial tensile tests. The change of compression set were used for assessment of the useful life and the time to threshold value were plotted against the reciprocal of absolute temperature to give the Arrhenius plot. The useful life at variable temperatures are obtained in the Arrhenius relationship.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.21 no.3
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• pp.51-57
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• 2021

In this paper, the relevance between Einstein's special theory of relativity (1905) and Bernoulli's fluid mechanics (1738), which motivates Shannon's theorem (1948), was derived from the AB=A/A=I dimension, and the Shannon's theorem channel code was simulated. When Bernoulli's fluid mechanics ΔP=pgh was applied to the Hallasan volcano Magma eruption, the dimensions and heights matched the measured values. The relationship between Einstein's special theory of relativity, Shannon's information theory, and the stack effect theory of fluid mechanics was analyzed, and the relationship between volcanic eruptions was mathematically proven. Einstein's and Bernoulli's conservation of energy and conservation of mass were the same in terms of bandwidth and power efficiency in Shannon's theorem.