• Title/Summary/Keyword: Structure and function

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Molecular Behavior and Electro-Chemical Properties of Dendrimer and Staff-type Polymer Monolayers in Crown Function Group (크라운 기능기를 포함한 덴드리머 및 Staff-type 고분자 단분자막의 분자거동 및 전기ㆍ화학적 특성)

  • 장정수
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.52 no.5
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    • pp.213-213
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    • 2003
  • We investigated the monolayer behavior at the air-water interface with metal solution, the surface morphologies and the electrical properties such as conductivity, The calculated conductivity values of pure water subphase and its complexes with L $i^{+}$ ions are 5.6$\times$10$^{-l6}$ and 1.9$\times$10$^{-14}$ [S/cm], respectively. And the calculated barrier height D values of pure water subphase and its complexes with Li. ions are 0.70 and 0.66 [eV], respectively. We also attempted to fabricate a crown dendrimer Langmuir-Blodgett (LB) films containing functional end group that could form a complex structure with metal ions. Also, we investigated the surface activity of dendrimer films at air-water interface. In AFM images. the larger domains irregularly shaped structures on the top while the smaller ones were free from such defects. In conclusion, it is demonstrated that the metal ion around dendrimer and polymer included crown function group can contribute to make formation of network structure among crown function group and result in change of electrical properties.s.s.

Molecular Behavior and Electro-Chemical Properties of Dendrimer and Staff-type Polymer Monolayers in Crown Function Group (크라운 기능기를 포함한 덴드리머 및 Staff-type 고분자 단분자막의 분자거동 및 전기ㆍ화학적 특성)

  • 장정수
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.52 no.5
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    • pp.213-218
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    • 2003
  • We investigated the monolayer behavior at the air-water interface with metal solution, the surface morphologies and the electrical properties such as conductivity, The calculated conductivity values of pure water subphase and its complexes with L $i^{+}$ ions are 5.6$\times$10$^{-l6}$ and 1.9$\times$10$^{-14}$ [S/cm], respectively. And the calculated barrier height D values of pure water subphase and its complexes with Li. ions are 0.70 and 0.66 [eV], respectively. We also attempted to fabricate a crown dendrimer Langmuir-Blodgett (LB) films containing functional end group that could form a complex structure with metal ions. Also, we investigated the surface activity of dendrimer films at air-water interface. In AFM images. the larger domains irregularly shaped structures on the top while the smaller ones were free from such defects. In conclusion, it is demonstrated that the metal ion around dendrimer and polymer included crown function group can contribute to make formation of network structure among crown function group and result in change of electrical properties.s.s.

Optimized purification and characterization of expressed hMC4R-TM2

  • Park, Yu-Geun;Song, Jooyoung;Kim, Yongae
    • Journal of the Korean Magnetic Resonance Society
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    • v.16 no.2
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    • pp.147-161
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    • 2012
  • Human melanocortin-4 receptor (hMC4R) among MC-Rs, expressed in the brain, is in charge of the control on energy homeostasis and food intake. The structure and function of human MC4R have been studied to understand their essential function and roles. To investigate the structure and function, it is necessary to prepare sufficient amounts of proteins. However, their expression and purification is demanding and time-consuming due to their innate insoluble and toxic properties. The heterozygous mutations of hMC4R, exchange of Asp 90 to Asn located in second transmembrane, cause severe obesity in human. To obtain purified hMC4R wt-TM2 for structural studies, it was first over-expressed and purified by fast protein liquid chromatography (FPLC) and then solution NMR studies were performed to get high-resolution spectra. In here, we established optimized purification scheme to get more purified target peptide.

Mammalian Sialyltransferase Superfamily : Structure and Function

  • Lee, Young-Choon
    • Proceedings of the Korean Society of Life Science Conference
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    • 2002.12a
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    • pp.13-19
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    • 2002
  • To elucidate the regulatory mechanism for expression of sialyl-glycoconjugates and their biological functions, ninetheen sialyltransferase cDNAs including eleven by our group or co-works have been cloned and characterized so far. The cloned sialyltransferases are classified into four families according to the carbohydrate linkages they synthesize: ${\alpha}2,3-sialyltransferase$ (ST3Gal I-VI), ${\alpha}$ 2,6-sialyltransferase (ST6Gal I), GalNAc ${\alpha}$ 2,6-sialyltransferase (ST6GalNAc I-VI), and ${\alpha}2,8-sialyltransferase$ (ST8Sia I-VI). Each of the sialyltransferase genes is differentially expressed in a tissue-, cell type-, and stage-specific manner. These enzymes differ in their substrate specificity and various biochemical parameters. However, enzymatic analysis conducted in vitro with recombinant enzyme revealed that one linkage can be synthesized by multiple enzymes. We present here an overview of structure and function of sialyltransferases performed by our group and co-works. Genomic structures and transcriptional regulation of two kinds of human sialyltransferase gene are also presented.

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Computer Analysis of Mathematical Model for Engine Control (엔진제어를 위한 수학적 모델의 컴퓨터 해석)

  • 김유남;우광방
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.38 no.9
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    • pp.724-732
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    • 1989
  • The structure of engine and its interaction are investigated and the construction of mathematical model for the performance evaluation is presented and then simulated. The total system is classified as air-fuel inlet element, intake manifold, combustion, and engine dynamics and their control function are schematically evaluated. Because of the model structure with general engine function and computer simulation of the chosen engine, physical characteristics of the corresponding engine and the engine data of normal operation state are used. According to the study, it is possible to predict the mixture rate by by the difference in the mass of fuel and air into cylinder and to evaluate and trace dynamic characteristic of operation state under various operating condition. The model characteristic under the transient operating condition makes it possible to effectively evaluate the operation of actual engine through the result of simulation.

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Robustness of discrete-time variable structure control to parametric uncertainties (매개변수의 불확실성에 대한 이산시간 가변구조 제어기법의 견실성)

  • 은용순;조동일
    • 제어로봇시스템학회:학술대회논문집
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    • 1997.10a
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    • pp.293-296
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    • 1997
  • Robust stability conditions for discrete-time variable structure control is proposed. Conventionally the discrete-time variable structure control method with a variable structure uncertainty compensator approach requires a bounded changing rate of the uncertainties to ensure robust stability. However, when uncertainties vary as a function of state variables, which occur with parametric uncertainties, it is not reasonable to assume a bounded variation on the uncertainties. In this paper, uncertainties are assumed to consist of exogenous disturbances and parametric uncertainties. An uncertainty compensator is used to deal with the former, and a robust stability condition is derived using Small Gain Theorem for the latter.

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Identification of Rigid Body Properties of the Mounted Structure with Improved Mass-Lines from Impact Hammer Tests (탄성지지된 구조물의 충격 햄머 실험에서 질량선의 개선을 통한 향상된 강체 특성 규명법)

  • Ahn, Se-Jin;Jeong, Weui-Bong;Hwang, Dae-Sun
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.11b
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    • pp.317-322
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    • 2002
  • There are many researches to identify the rigid body properties from the mass-line obtained by impact hammer testing. The correct rigid body properties of the structure may be estimated if the mass-line of the structure could be obtained exactly. When the structure is mounted by elastic materials, the mass-line cannot be read correctly from the impulse response spectrum. The reason is due to the effects of rigid body modes of mounted structure. In this paper, the effects of rigid body modes of mounted structure to the mass-line are discussed and the method to remove these effects is also presented.

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Structure-borne Noise Analysis of Marine Diesel Engine Considering Receptance of Hull Structure at Mounting Point (선체 마운트 지지점에서의 리셉턴스를 고려한 선박용 디젤 엔진의 고체전달음 해석)

  • Jang, Seong-Gil;Jeong, Weui-Bong;Hong, Chin-Suk;Bae, Soo-Ryong
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.21 no.2
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    • pp.120-128
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    • 2011
  • This paper presents an efficient method to analyze noise and vibration of marine diesel engines mounted on flexible hull structure. The analysis model should in general include the hull structure, leading to lots of computational efforts. To minimize the computational efforts, in this paper, the transfer synthesis utilizing the receptance at the mounting points is proposed. The procedure is then verified by comparing the results with those from the full model calculation. The effects of flexible hull structure on the acoustic power from engine block are finally investigated. It is found that the effect of the hull is significant when the receptance of hull structure is similar to or greater than that of mount or engine block.

A Study on the Improvement of Easy Elevator Equipment (간이용 엘리베이터 장치 개선에 관한 연구)

  • Wee, Sung-Dong;Gu, Hal-Bon
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.09a
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    • pp.82-88
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    • 2001
  • Manufactured easy elevator can drives from the first floor to fifth floor as sequence control circuit in cause opening than existing equipment of experiment and practice, the structure of in the first implementation process are hand-worked control component with push-button, L/S and relay, it is structured a lamp to express that the door open and moving of cage by mechanical action of For/Rev motor-braker of which load. The second structure of implement process to control from the first floor to the fifth floor with the PLC elevator program can control by the sensor of hand-operated function of L/Sl~L/S5 in time that the S/Wl~S/W5 of PLC control panel operates to the For/Rev. The function of two kind process that an elevator is driven by PLC program and the sequence control relay circuit is a mechanical relay sequence control field and it is equipment apparatus of it to get appropriately the technology of For/Rev in that mechanical operating cause of a load using the PLC program. Also the wring circuit using a plug, dissembly. the circuit and the principle of component, and PLC program with the function test can be used the implementation field to the total technology theory about FA.

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Issues of Discourse Studies in Korean Language Education (한국어교육학에서의 담화 연구 분석)

  • Kang, Hyounhwa
    • Journal of Korean language education
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    • v.23 no.1
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    • pp.219-256
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    • 2012
  • The aim of this study is to observe the trend of discourse study in language education and analyze the main issues by investigating the literatures related to discourse in Korean language education in the last ten years. This study observed the discourse study conducted in Korean language education from the perspectives of study subject, study method and study data. Moreover, based on the results, it estimated the achievements and effectiveness of the discourse study conducted in Korean language education. The subject of discourse study was mainly dealt with discourse function, discourse pattern, discourse marker, discourse structure. In the study methods, analysis of corpus and survey were mainly used as the study methods, and spoken corpus, written corpus and semi-spoken corpus were used as study materials. In particular, the semi-spoken corpus was used at a very high rate among them. This showed that discourse study in Korean language education was mainly focused on spoken corpus study. This study divided the detailed field of Korean language education into four fields of linguistic knowledge, communication function, teaching activities and learning activities, and observed the trends of discourse study in each field. Overall, it was recognized that relatively many studies were focused on linguistic knowledge, particularly in pragmatic perspective. It can be said that the study based on discourse has a language educational effectiveness in that it is based on actual data and improves practical communication skills in the environment of various languages.