• Molecules and Cells
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• 제37권4호
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• pp.322-329
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• 2014

N-acetylglucosamine kinase (GlcNAc kinase or NAGK; EC 2.7.1.59) is highly expressed and plays a critical role in the development of dendrites in brain neurons. In this study, the authors conducted structure-function analysis to verify the previously proposed 3D model structure of GlcNAc/ATP-bound NAGK. Three point NAGK mutants with different substrate binding capacities and reaction velocities were produced. Wild-type (WT) NAGK showed strong substrate preference for GlcNAc. Conversion of Cys143, which does not make direct hydrogen bonds with GlcNAc, to Ser (i.e., C143S) had the least affect on the enzymatic activity of NAGK. Conversion of Asn36, which plays a role in domain closure by making a hydrogen bond with GlcNAc, to Ala (i.e., N36A) mildly reduced NAGK enzyme activity. Conversion of Asp107, which makes hydrogen bonds with GlcNAc and would act as a proton acceptor during nucleophilic attack on the ${\gamma}$-phosphate of ATP, to Ala (i.e., D107A), caused a total loss in enzyme activity. The overexpression of EGFP-tagged WT or any of the mutant NAGKs in rat hippocampal neurons (DIV 5-9) increased dendritic architectural complexity. Finally, the overexpression of the small, but not of the large, domain of NAGK resulted in dendrite degeneration. Our data show the effect of structure on the functional aspects of NAGK, and in particular, that the small domain of NAGK, and not its NAGK kinase activity, plays a critical role in the upregulation of dendritogenesis.

• The Journal of Asian Finance, Economics and Business
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• 제7권10호
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• pp.141-148
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• 2020

This paper analyzes factors affecting the debt maturity structure of enterprises listed on the Vietnam stock market. The panel data of research sample includes 549 non-financial listed enterprises on the Vietnam stock market from 2009 to 2019. The Generalized Least Square (GLS) tool is employed to address econometric issues and to improve the accuracy of the regression coefficients. In this research, debt maturity structure is the dependent variable. Capital structures, fixed assets, liquidity, firm size, asset maturity, profitability, corporate income tax, gross domestic product, inflation rate, credit growth scale are independent variables in the study. The model results show, that among the factors affecting the structure of debt maturity, the capital structure, asset structure, and firm size have the highest estimation coefficients, which shows that capital structure, asset structure, and firm size plays an important role in the decision-making process of debt maturity structure. The empirical results show that there are differences in the impact of these factors on the debt maturity structures in state-owned enterprises and non-state enterprises listed on the Vietnam stock market. The findings of this article are useful for business administrators, helping business managers make the right financial decisions to determine the target debt maturity structure in enterprises.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.223-226
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• 1997

Usually, the Evolutionary Algorithms(EAs) are considered more efficient for optimal, system design because EAs can provide higher opportunity for obtaining the global optimal solution. This paper presents a mechanism of co-evolution consists of the two genetic algorithms(GAs). This mechanism includes host populations and parasite populations. These two populations are closely related to each other, and the parasite populations plays an important role of searching for useful schema in host populations. Host population represented by feedforward neural network and the result of co-evolution we will find the optimal structure of the neural network. We used the genetic algorithm that search the structure of the feedforward neural network, and evolution strategies which train the weight of neuron, and optimize the net structure. The validity and effectiveness of the proposed method is exemplified on the stabilization and position control of the inverted-pendulum system.

• 디지털산업정보학회논문지
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• 제12권3호
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• pp.167-179
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• 2016

Online games, by a massive influx of many players, it has diverse situations in which emotion is generated. Emotion plays an important role that helps players to interact and immerse in game. In the previous games, simple structures are used to express emotion. By increasing the user's needs of emotion in the game, it is necessary to structure a various type of emotion. In this paper, the game components were classified as background, object, and character in order to analyze emotion structurally in game. We defined how to use the rule of emotion, and applied to League of legend, Cyphers and World of Warcraft which belong to the AOS genre. The AOS game is well-suited for analyzing emotion structure, because a various emotional changes and situations can arise in the game. Through this paper, it was discovered similarities emotion to be used in online games. It is expected to generalize the emotion in the game by analyzing the emotional structure of more games in future.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1994년도 춘계학술대회 and 제3회 신약개발 연구발표회
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• pp.41-49
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• 1994

The most common conventional method of discovering a drug involves a massive screening of a large number of compounds in chemical libraries or in the extracts from natural sources such as plants or microbial broths followed by chemical modification of one or more active compounds to improve their properties as a drug. When the three-dimensional structure of the target molecule for which the drug is searched is known the drug discovery process can be significantly simplified, This is especially true when the three-dimensional structure of a complex between the target and a lead compound is known. In this lecture our experience on the structure-based drug design for human CDK2(cyclin-dependent protein kinase 2) will be discussed with special emphasis on the strength and weakness of this approach of drug discovery. The regulation of the activity of CDK2 plays an important role in the cell proliferation of normal and cancer cells.

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2003년도 추계종합학술대회 논문집
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• pp.132-139
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• 2003

본 논문은 공개키 기반구조(PKI - Public Key Infrastructure)에서 중추적인 역할을 담당하는 공개키 인증시스템을 설계하고 구현한다. 본 논문에서는 인증기관의 역할을 수행할 수 있는 공개키 인증시스템의 요구사항 및 특징을 분석하여, 실제 보안서비스가 제공 가능한 인증과정은 HA 및 FA한테 위임하고 설계한다. 보안구조는 Root CA와 Home Network 및 Foreign Network로 구성되어 있고, 필요할 때 CA은 HA 및 FA한테 인증을 위탁한다.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2008년도 한국우주과학회보 제17권2호
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• pp.30.4-31
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• 2008

Formation of longitudinally wave-like plasma density structure in the low-latitude F region is now a well-known phenomenon from the extensive studies in recent years. Observations of plasma density from multiple satellites have shown that the locations of the crests of the plasma density that are seen to be stationary during daytime are shifted after sunset. This phenomenon has been understood to be caused by eastward drift of the ionosphere at night. However, the eastward drift velocity of the ionosphere after sunset is not sufficiently large enough to explain the day-night difference in the longitudinal density structure. The just after sunset and the nighttime ionospheric morphologymay be affected by this drift after sunset. In this study, we will investigate the temporal variation of the phase of the longitudinal density structure and vertical plasma drift by analyzing the ROCSAT-1, TIMED/GUVI, and DMSP data and verify the role of the vertical drift after sunset in the change of the phase of the longitudinal density structure.

• 한국태양에너지학회 논문집
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• 제22권1호
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• pp.73-80
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• 2002

This is study of the planning of thermal insulation to prevent heat loss in a basement, is aimed at investigating the heat loss from the basement space and basement structures. The results analyzed in these researches are as follows; To analyze the heat loss from basement structures, this study experimented on the heat flow phenomenon of a non-insulation structure and two insulation structure models. From the result, the interior surface temperature of two insulation structures(B, C, model) showed an equal temperature, but the interior surface temperature of a non-insulation structure (A model) is different from the two models, Therefore, we understand that the insulator constructed in the basement structure makes a role of preventing the heat loss from the basement. In addition, the exterior surface temperature of two insulation structure models showed an equal temperature. Specially, judging from the temperature difference of C model. we understand that the performance of insulator is low under the definite depth of underground. The thermal insulation design should be constructed under the definite depth of underground considering outdoor and building conditions.

• 소음진동
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• 제9권3호
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• pp.493-501
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• 1999

The vibration modes of resilient mounting system and foundation structure which support diesel engine/generator set and acoustic enclosure walls play an important role in the vibration transmission process. So, it is necessary to perform vibration mode analysis of resilient mounting system and foundation structure. For some reasons, if the vibration modal analysis of resilient mounting system and foundation structure of acoustic enclosure could be simultaneously done by finite element method, it would be very efficient approach. In this paper, vibration modal analysis method using finite element method for multi stage mounting system having n d.o.f model was proposed. Vibration analysis of single and double stage resilient mounting system was performed to verify the validity of the proposed method. Also frequency response results were compared in case of rigid foundation model and finite element foundation model which was compared with experimental modal analysis results.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 심포지엄 논문집 정보 및 제어부문
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• pp.3-5
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• 2006

Recent advances in the internet infrastructure have resulted in a large number of huge Web sites and portals worldwide. These Web sites are being visited by various types of users in many different ways. Among all the web page access sequences from different users, some of them occur so frequently that may need an attention from those who are interested. We call them frequent access patterns and access sequences that can be frequent the candidate patterns. Since these candidate patterns play an important role in the incremental Web mining, it is important to efficiently generate, add, delete, and search for them. This thesis presents a novel tree structure that can efficiently store the candidate patterns and a related set of algorithms for generating the tree structure adding new patterns, deleting unnecessary patterns, and searching for the needed ones. The proposed tree structure has a kind of the 3 dimensional link structure and its nodes are layered.