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Model Structuring Technique by A Knowledge Representation Scheme: A FMS Fractal Architecture Example (지식 표현 기법을 이용한 모델 구조의 표현과 구성 : 단편구조 유연생산 시스템 예)

  • 조대호
    • Journal of the Korea Society for Simulation
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    • v.4 no.1
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    • pp.1-11
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    • 1995
  • The model of a FMS (Flexible Manufacturing System) admits to a natural hierarchical decomposition of highly decoupled units with similar structure and control. The FMS fractal architecture model represents a hierarchical structure built from elements of a single basic design. A SES (System Entity Structure) is a structural knowledge representation scheme that contains knowledge of decomposition, taxonomy, and coupling relationships of a system necessary to direct model synthesis. A substructure of a SES is extracted for use as the skeleton for a model. This substructure is called pruned SES and the extraction operation of a pruned SES from a SES is called pruning (or pruning operation). This paper presents a pruning operation called recursive pruning. It is applied to SES for generating a model structure whose sub-structure contains copies if itself as in FMS fractal architecture. Another pruning operation called delay pruning is also presented. Combined with recursive pruning the delay pruningis a useful tool for representing and constructing complex systems.

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A Tessellation of a Polynomial Curve by a Sequential Method (다항식곡선으로부터 순차적 방법에 의한 점열의 생성)

  • Ju S.Y.
    • Korean Journal of Computational Design and Engineering
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    • v.11 no.3
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    • pp.205-210
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    • 2006
  • Curve tessellation, which generates a sequence of points from a curve, is very important for curves rendering on a computer screen and for NC machining. For the most case the sequence of discrete points is used rather than a continuous curve. This paper deals with a method of tessellation by calculating the maximal deviation of a curve. The maximal deviation condition is introduced to find the point with the maximal chordal deviation on a curve segment. In the previous research a curve tessellation was tried by the subdivision method, that is, a curve is subdivided until the maximal chordal deviation is less than the given tolerance. On the other hand, a curve tessellation by sequential method is tried in this paper, that is, points are generated successively by using the local property of a curve. The sequential method generates relatively much less points than the subdivision method. Besides, the sequential method can generate a sequence of points from a spatial curve by approximation to a planar curve. The proposed method can be applied for high-accuracy curve tessellation and NC tool-path generation.

LIFTING T-STRUCTURES AND THEIR DUALS

  • Yoon, Yeon Soo
    • Journal of the Chungcheong Mathematical Society
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    • v.20 no.3
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    • pp.245-259
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    • 2007
  • We define and study a concept of $T^f$-space for a map, which is a generalized one of a T-space, in terms of the Gottlieb set for a map. We show that X is a $T_f$-space if and only if $G({\Sigma}B;A,f,X)=[{\Sigma}B,X]$ for any space B. For a principal fibration $E_k{\rightarrow}X$ induced by $k:X{\rightarrow}X^{\prime}$ from ${\epsilon}:PX^{\prime}{\rightarrow}X^{\prime}$, we obtain a sufficient condition to having a lifting $T^{\bar{f}}$-structure on $E_k$ of a $T^f$-structure on X. Also, we define and study a concept of co-$T^g$-space for a map, which is a dual one of $T^f$-space for a map. We obtain a dual result for a principal cofibration $i_r:X{\rightarrow}C_r$ induced by $r:X^{\prime}{\rightarrow}X$ from ${\iota}:X^{\prime}{\rightarrow}cX^{\prime}$.

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Solution State Structure of pA1, the Mimotopic Peptide of Apolipoprotein A-I, by NMR Spectroscopy

  • Kim, Hyo-Joon;Won, Ho-Shik
    • Bulletin of the Korean Chemical Society
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    • v.32 no.9
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    • pp.3425-3428
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    • 2011
  • Apolipoprotein A-I (Apo A-I) is a major component for high density lipoproteins (HDL). A number of mimetic peptides of Apo A-I were screened from the phase-displayed random peptide library by utilizing monoclonal antibodies (A12). Mimetic peptide for A12 epitope against Apo A-I was selected as CPFARLPVEHHDVVGL (pA1). From the BLAST search, the mimetic peptide pA1 had 40% homology with Apo A-I. As a result of the structural determination of this mimotope using homo/hetero nuclear 2D-NMR techniques and NMR-based distance geometry (DG)/molecular dynamic (MD) computations, DG structure had low penalty value of 0.3-0.7 ${\AA}^2$ and the total RMSD was 0.6-1.6 ${\AA}$. The mimotope pA1 exhibited characteristic conformation including a ${\beta}$-turn from Pro[7] to His[11].

Analysis of Oil Supply Characteristics for Reciprocating Compressor (왕복동 압축기 오일 급유 특성 분석)

  • Lee, Byeong-Yeong;Ko, Han-Seo;Ryu, Ki-O;Youn, Young;Park, Seong-Woo
    • 유체기계공업학회:학술대회논문집
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    • 2006.08a
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    • pp.545-546
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    • 2006
  • A problem of oil supply for a reciprocating compressor is very significant for an evaluation of reliability. Since a rotational motion of a crank shaft for the reciprocating compressor with small capacity is used for a power source of oil supply, a centrifugal force of the rotational shaft provides a stroke of oil inside the shaft like a centrifugal pump. The pumped oil rises following an inner wall and provided to a bearing passed through an oil supply hole at the side of the shaft for lubrication of the bearing. In this study, the amount of oil supply has been investigated by a numerical analysis for various conditions such as a shape of a groove, rpm of the compressor, and a shape of a flow channel. Also, a method of increasing oil supply for a low rpm has been studied so that the function can be improved for a variable condition.

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Development of a Real-time Vehicle Driving Simulator

  • Kim, Hyun-Ju;Park, Min-Kyu;Lee, Min-Cheoul;You, Wan-Suk
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.51.2-51
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    • 2001
  • A vehicle driving simulator is a virtual reality device which makes a human being feel as if the one drives a vehicle actually. The driving simulator is effectively used for studying interaction of a driver-vehicle and developing the vehicle system of new concepts. The driving simulator consists of a motion platform, a motion controller, a visual and audio system, a vehicle dynamic analysis system, a vehicle operation system and etc. The vehicle dynamic analysis system supervises overall operation of the simulator and also simulates dynamic motion of a multi-body vehicle model in real-time. In this paper, the main procedures to develop the driving simulator are classified by 4 parts. First, a vehicle motion platform and a motion controller, which generates realistic motion using a six degree of freedom Stewart platform driven hydraulically. Secondly, a visual system generates high fidelity visual scenes which are displayed on a screen ...

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Fabrication of a CNT Filter for a Microdialysis Chip

  • An, Yun-Ho;Song, Si-Mon
    • Molecular & Cellular Toxicology
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    • v.2 no.4
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    • pp.279-284
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    • 2006
  • This paper describes the fabrication methods of a carbon nanotube (CNT) filter and a microdialysis chip. A CNT filter can help perform dialysis on a microfluidic chip. In this study, a membrane type of a CNT filter is fabricated and located in a microfluidic chip. The filter plays a role of a dialysis membrane in a microfluidic chip. In the fabrication process of a CNT filter, individual CNTs are entangled each other by amide bonding that is catalyzed by 1-Ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) and N-hydroxysuccinimide (NHS). The chemically treated CNTs are shaped to form a CNT filter using a PDMS film-mold and vacuum filtering. Then, the CNT filter is sandwiched between PDMS substrates, and they are bonded together using a thin layer of PDMS prepolymer as adhesive. The PDMS substrates are fabricated to have a microchannel by standard photo-lithography technique.

Robust Pole Assignment in a Specified Disk

  • Nguyen, Van-Giap;Nguyen, Tan-Tien;Lee, Gun-You;Kim, Sang-Bong
    • Transactions on Control, Automation and Systems Engineering
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    • v.2 no.2
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    • pp.116-120
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    • 2000
  • This paper presents a method to assign robustly the closed loop system's poles in a specified disk by a state feedback for a linear time invariant system with structured or unstructured uncertainties. THe proposed robust design procedure includes two steps. Firstly, the perturbed closed loop matrix $A_{cl p}$ = $A_{cl}$ + Δ$A_{cl}$ is rearranged such that it is a function of the nominal closed loop matrix $A_{cl}$. Hence, we can control the positions of the perturbed closed loop poles by choosing $A_{cl}$ appropriately. Secondly, the feedback control law F that assigns the closed loop poles of the perturbed system in a specified disk is determined from the equation $A_{cl}$ = A + BF. A procedure for finding F is proposed based on partitioning every matrix of the equation $A_{cl}$ = A + BF in the horizontal direction.

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A Study on the Hypertext-space based on the Rhizome characteristic (리좀 특성이 반영된 하이퍼텍스트스페이스에 관한 연구)

  • Ahn, Hyun-Jeong
    • Korean Institute of Interior Design Journal
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    • v.20 no.4
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    • pp.63-73
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    • 2011
  • In the middle of that a information form is being formlessly changed to diverse deirections, a design and a space as physical consequence show not only a allegory but mutually relational charicteristic meaning a nonboundary and nonlinear form by development of modem digital culture. Following development of the modern digital culture, a design and space which are physical results, show a point of correlative specificity, allegory, nonlinear and nonboundary, Not only a design and culture but also various circles handle a hypertext as a representative pivot in this change. this has same contexts as rhizome possessing a asignifiante and nomadic characteristic said by Felix Guattari and Gilles Deleuze. An ideal of rhizome space shows historical decisions, unexpected accidents, a concepts, an individual. a group, social compositions above an contrifugal exterior force, This study examines into surroundings designed by a hypertext and rhizome through a case accordingly and infers an ultramodern characteristic in conventional precognition with synthesizing a peculiarity of the digital generation space.

Conserved Roles of MonA in Fungal Growth and Development in Aspergillus Species

  • Son, Ye-Eun;Park, Hee-Soo
    • Mycobiology
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    • v.47 no.4
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    • pp.457-465
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    • 2019
  • MonA is a subunit of a guanine nucleotide exchange factor that is important for vacuole passing and autophagy processes in eukaryotes. In this study, we characterized the function of MonA, an orthologue of Saccharomyces cerevisiae Mon1, in the model fungus Aspergillus nidulans and a toxigenic fungus A. flavus. In A. nidulans, the absence of AnimonA led to decreased fungal growth, reduced asexual reproduction, and defective cleistothecia production. In addition, AnimonA deletion mutants exhibited decreased spore viability, had reduced trehalose contents in conidia, and were sensitive to thermal stress. In A. flavus, deletion of AflmonA caused decreased fungal growth and defective production of asexual spores and sclerotia structures. Moreover, the absence of monA affected vacuole morphology in both species. Taken together, these results indicate that MonA plays conserved roles in controlling fungal growth, development and vacuole morphology in A. nidulans and A. flavus.