• Title/Summary/Keyword: unique range set

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Aerodynamic Characteristics and Shape Optimization of Airfoils in WIG Craft Considered Ground Effect (지면효과를 고려한 WIG 선 익형의 공력특성 및 형상최적화)

  • Lee, Ju-Hee;Kim, Byeong-Sam;Park, Kyoung-Woo
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.30 no.11 s.254
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    • pp.1084-1092
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    • 2006
  • Shape optimization of airfoil in WIG craft has been performed by considering the ground effect. The WIG craft should satisfy various aerodynamic characteristics such as lift, lift to drag ratio, and static height stability. However, they show a strong trade-off phenomenon so that it is difficult to satisfy aerodynamic properties simultaneously. Optimization is carried out through the multi-objective genetic algorithm. A multi-objective optimization means that each objective is considered separately instead of weighting. Due to the trade-off, pareto sets and non-dominated solutions can be obtained instead of the unique solution. NACA0015 airfoil is considered as a baseline model, shapes of airfoil are parameterized and rebuilt with four-Bezier curves. There are eighteen design variables and three objective functions. The range of design variables and their resolutions are two primary keys for the successful optimization. By two preliminary optimizations, the variation can be reduced effectively. After thirty evolutions, the non-dominated pareto individuals of twenty seven are obtained. Pareto sets are all the set of possible and excellent solution across the design space. At any selections of the pareto set, these are no better solutions in all design space.

The Evaluation of Usefulness of the Manufactured DTAB (Double Tilt Angle Board) System (Double Tilt Angle Board (DTAB)의 자체 제작에 관한 유용성 평가)

  • Lee, Joung-Jin;Jang, In-Gi;Kim, Wan-Sun
    • The Journal of Korean Society for Radiation Therapy
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    • v.18 no.1
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    • pp.43-51
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    • 2006
  • Purpose: To resolution of A hospital-handmade modification double tilt angle immobilization system (DTAB immobilization system) and to report the clinical results of it. Material and Methods: It was developed in conjunction with the breast board for patients unable to achieve and maintain the desired uncomfortable respiration and position of set-up needed in the treatment of RT (This custom design provides an alternative to accomplishing this desired head angle needed to relax position treatment area, realizing that the lenses totally protected eye-ball out) By using the angled breast board and SBDD(small bowel device), reproducibility of set-up and patient comfort were addressed throughout the simulation, computed tomography planning and treatment process. Results: Usually patients the error range-within 5 mm. When use of Aqua patients error range-within 3 mm. Conclusion: It was constructed in tandem with a unique custom-built double tilt angle board (DTAB). It was designed to eliminate clinical set-up problems with head immobilization and instability during treatment, thus providing for a more comfortable head rest for the patient.

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Binary Backtracking Algorithm for Sudoku (스도쿠 퍼즐을 위한 이진역추적 알고리즘)

  • Lee, Sang-Un
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.17 no.4
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    • pp.155-161
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    • 2017
  • This paper suggests polynomial time solution algorithm for Sudoku puzzle problem. This problem has been known NP (non-deterministic polynomial time)-complete. The proposed algorithm set the initial value of blank cells to value range of [$1,2,{\cdots},9$]. Then the candidate set values in blank cells deleted by preassigned clue in row, column, and block. We apply the basic rules of Stuart, and proposes two additional rules. Finally we apply binary backtracking(BBT) technique. For the experimental Sudoku puzzle with various categories of solution, the BBT algorithm can be obtain all of given Sudoku puzzle regardless of any types of solution.

A Study on the Permissible Gain Ranges of the P and PI Controllers for the Retarded Processes (시간지연을 갖는 제어대상에 대한 P. PI제어의 유효 게인 조정 범위에 관한 연구)

  • 강인철;최순만;최재성
    • Journal of Advanced Marine Engineering and Technology
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    • v.25 no.5
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    • pp.1086-1090
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    • 2001
  • In this paper, a method deciding the permissible gains of the P and PT controllers for a retarded process under stable condition is proposed. For analysis, the controlled process is assumed to be first-order system with time delay. At first, the adjustable parameter sets causing stability limit are obtained based on the frequency domain condition which makes the roots of the characteristic equation locate on the imaginary axis. And the cut-in frequency ${\omega}_p$ to bring the parameter set to P control from PI control is derived is derived in terms of L and $T_m$ then ${\omega}_p$ is used to compute the maximum gain with stable condition. The results indicate that the permissible controller gains can be described by a unique if parameters L and $T_m$ are know.

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Polarity Probing Two-Photon Fluorophores Based on [2.2]Paracyclophane

  • Woo, Han-Young;Korystov, Dmitry;Jin, Young-Eup;Suh, Hong-Suk
    • Bulletin of the Korean Chemical Society
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    • v.28 no.12
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    • pp.2253-2260
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    • 2007
  • A series of tetra donor substituted [2.2]paracyclophane-based two-photon absorption (TPA) fluorophores were synthesized in neutral and cationic forms. The imaging activity of overall set of fluorophores was studied by the two-photon induced fluorescence (TPIF) method in a range of solvents. We also measured a clear progression toward a longer photoluminescence lifetime with increasing solvent polarity (intrinsic photoluminescence lifetime, τi: ~2 ns in toluene → 12-16 ns in water). The paracyclophane fluorophores with this unique property can be utilized as an optical polarity probe for the biomolecular substrates. The combined measurement of the two-photon fluorescence microscopy (TPM) cell image and TPIF lifetime can give us a better understanding of the biological processes and local environments in the cells.

Optimal Solution and Comparison for the Augmented Multi-item Random Orders (복수품목 랜덤 결함주문정책의 최적해와 비교)

  • 권희철;김만식
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.10 no.16
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    • pp.129-132
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    • 1987
  • Multi-item inventory problems can be well characterized by the nature of interaction of the quantities and timing. This interaction may be due to the effect of certain combination of orders. It is that the set-up cost of ordering individual items can be saved by jointly ordering at a time. This study finds a decision criteria of optimum inventory policy through the comparisons of individual multi-item order policy(IMP), joint multi-item order policy(JMP), augmented multi-item order policy(AMP) in cost ratio. Subsequently we assume that there exists a unique optimum order level corresponding to an optimum reorder range for the augmented multi-item order, at which a cost saying is maximum.

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Parameter convergence properties for MRAC system with a constant reference signal tracking (일정한 기준신호를 추적하는 MRAC시스템에 대한 파라미터 수렴특성)

  • 민병태;김성덕;양해원
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.13 no.1
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    • pp.1-11
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    • 1988
  • In this paper, the boundedness of adjustable parameters for the model reference adaptive control(MRAC) system using a constant reference signal is discussed. This analysis is motivated by that it is possibel to verify the existence, boundedness and bounded range of the parameter as well as the stability of the adaptive system with an alternative propoerty of Lyapunov function. For two adaptive laws; a general gradient mothod(GGM) and a least square method(LSM), unique solution set in parameter space can be estabilished by a new approach suggeste here. Computer simulation results to show the effect of parameter space analysis are also examined.

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Polypyrrole Film Studied by Three-Parameter Ellipsometry

  • 김동래;이덕환;백운기
    • Bulletin of the Korean Chemical Society
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    • v.17 no.8
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    • pp.707-712
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    • 1996
  • Growth and changes of electronically conducting polypyrrole (PPy) in the form of thin films polymerized on metal electrodes were investigated by electrochemical and in situ three-parameter ellipsometry methods at the wavelength of 632.8 nm. Although the optical equations produced multiple sets of solution, it was possible to determine a unique set of thickness and the optical constants of a film by auxiliary measurements and/or physical reasoning. The changes in the thickness and the optical properties of the polymers during polymerization and electrochemical oxidation/reduction was successfully followed by the three-parameter ellipsometric technique. The optical properties of the polymers continuously changed as the film grew. The imaginary part of the refractive index of polypyrrole seemed to be dominantly determined by the existence of an absorption band around the visible range.

Identification of new major histocompatibility complex-B Haplotypes in Bangladesh native chickens

  • Thisarani Kalhari Ediriweera;Prabuddha Manjula;Jaewon Kim;Jin Hyung Kim;Seonju Nam;Minjun Kim;Eunjin Cho;Mohammad Shamsul Alam Bhuiyan;Md. Abdur Rashid;Jun Heon Lee
    • Animal Bioscience
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    • v.37 no.5
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    • pp.826-831
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    • 2024
  • Objective: The major histocompatibility complex in chicken demonstrates a great range of variations within varities, breeds, populations and that can eventually influence their immuneresponses. The preset study was conducted to understand the major histocompatibility complex-B (MHC-B) variability in five major populations of Bangladesh native chicken: Aseel, Hilly, Junglefowl, Non-descript Deshi, and Naked Neck. Methods: These five major populations of Bangladesh native chicken were analyzed with a subset of 89 single nucleotide polymorphisms (SNPs) in the high-density MHC-B SNP panel and Kompetitive Allele-Specific polymerase chain reaction genotyping was applied. To explore haplotype diversity within these populations, the results were analyzed both manually and computationally using PHASE 2.1 program. The phylogenetic investigations were also performed using MrBayes program. Results: A total of 136 unique haplotypes were identified within these five Bangladesh chicken populations, and only one was shared (between Hilly and Naked Neck). Phylogenetic analysis showed no distinct haplotype clustering among the five populations, although they were shared in distinct clades; notably, the first clade lacked Naked Neck haplotypes. Conclusion: The present study discovered a set of unique MHC-B haplotypes in Bangladesh chickens that could possibly cause varied immune reponses. However, further investigations are required to evaluate their relationships with global chicken populations.

Work Domain Analysis Based on Abstraction Hierarchy: Modelling Concept and Principles for Its Application (추상화계층에 기반한 작업영역분석의 모델링 개념 및 적용 원칙)

  • Ham, Dong-Han
    • Journal of the Korea Safety Management & Science
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    • v.15 no.3
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    • pp.133-141
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    • 2013
  • As a work analysis technique, Work Domain Analysis (WDA) aims to identify the design knowledge structure of a work domain that human operators interact with through human-system interfaces. Abstraction hierarchy (AH) is a multi-level, hierarchical knowledge representation framework for modeling the functional structure of any kinds of systems. Thus, WDA based on AH aims to identify the functional knowledge structure of a work domain. AH has been used in a range of work domains and problems to model their functional knowledge structure and has proven its generality and usefulness. However, many of researchers and system designers have reported that it is never easy to understand the concepts underlying AH and use it effectively for WDA. This would be because WDA is a form of work analysis that is different from other types of work analysis techniques such as task analysis and AH has several unique characteristics that are differentiated from other types of function analysis techniques used in systems engineering. With this issue in mind, this paper introduces the concepts of WDA based on AH and offers a comprehensive list of references. Next, this paper proposes a set of principles for effectively applying AH for work domain analysis, which are developed based on the author's experiences, consultation with experts, and literature reviews.