• Title/Summary/Keyword: semi-closed

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SEVERAL KINDS OF INTUITIONISTIC FUZZY OPEN SETS AND INTUITIONISTIC FUZZY INTERIORS

  • Kim, Chang-Su;Kang, Jeong-Gi;Kim, Myoung-Jo;Ko, Mi-Young;Park, Mi-Ran
    • Honam Mathematical Journal
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    • v.32 no.2
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    • pp.307-331
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    • 2010
  • The notion of intuitionistic fuzzy semi-pre interior (semi-pre closure) is introduced, and several related properties are investigated. Characterizations of an intuitionistic fuzzy regular open set, an intuitionistic fuzzy semi-open set and an intuitionistic fuzzy ${\gamma}$-open set are provided. A method to make an intuitionistic fuzzy regular open set (resp. intuitionistic fuzzy regular closed set) is established. A relation between an intuitionistic fuzzy ${\gamma}$-open set and an intuitionistic fuzzy semi-preopen set is considered. A condition for an intuitionistic fuzzy set to be an intuitionistic fuzzy ${\gamma}$-open set is discussed.

Semi-active control of a vehicle suspension for the ride quality improvement (승차감 향상을 위한 자동차 현가장치의 반능동제어에 관한 연구)

  • Park, Ho.;Oh, Jae-Eung
    • 제어로봇시스템학회:학술대회논문집
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    • 1990.10a
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    • pp.783-788
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    • 1990
  • Computer simulation is carried out for passive, active, and semi-active suspension system. Each RMS and frequency response to road profile input is calculated for comparison and evaluation of the performance. The vibration analysis and active control of the quarter model of a vehicle suspension is studied in order to evaluate the alternative control laws. This paper derives an optimal closed-loop feedback law for the semi-active suspension that justifies the clipped optimal approach.

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ON M-OPEN MAPPINGS

  • Min, Won Keun;Chang, Hong Soon
    • Korean Journal of Mathematics
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    • v.7 no.1
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    • pp.117-121
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    • 1999
  • In this paper, we introduce $m$-open(closed) mappings by $m$-sets, and obtain a number of their properties. In particular, $m$-open(closed) mappings are used to extend known results for ${\alpha}$-open mapping, semi-open mappings and preopen mappings.

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Nonlinear Control of an Automatic Transmission Using Sliding Mode (슬라이딩모드를 이용한 자동변속기의 비선형제어)

  • 조승호
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.19 no.3
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    • pp.605-614
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    • 1995
  • In the automatic transmission using planetary gear there exists nonlinearities due to the finite difference between gear ratios, which yield torque hole during shift and influence on the ride quality and life of clutch. Based on the reaction carrier and converter turbine speed sliding functions are defined. Nonlinear closed-loop control laws are derived using them. Computer simulation shows that the closed loop design is better than the open loop design and semi-closed loop design.

GENERALIZED NORMALITY IN RING EXTENSIONS INVOLVING AMALGAMATED ALGEBRAS

  • Kwon, Tae In;Kim, Hwankoo
    • Korean Journal of Mathematics
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    • v.26 no.4
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    • pp.701-708
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    • 2018
  • In this paper, seminormality and t-closedness in ring extensions involving amalgamated algebras are studied. Let $R{\subseteq}T$ be a ring extension with ideals $I{\subseteq}J$, respectively such that J is contained in the conductor of R in T. Assume that T is integral over R. Then it is shown that ($R{\bowtie}I$, $T{\bowtie}J$) is a seminormal (resp., t-closed) pair if and only if (R, T) is a seminormal (resp., t-closed) pair.

An Analysis of the Student's Algebra Word Problem Solving Process (대수 문장제 해결을 위한 학생들의 풀이 과정 분석: 일련의 표시(Chain of signification) 관점의 사례연구)

  • Park, Hyun-Jeong;Lee, Chong-Hee
    • School Mathematics
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    • v.9 no.1
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    • pp.141-160
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    • 2007
  • The purpose of this paper was to evaluate how students apply prior knowledge or experience in solving algebra word problems from the chain of signification-based perspective. Three middle school students were evaluated in this case study. The results showed that the subjects formed similarities in the process of applying knowledge needed for solving a problem. The student A and C used semi-open-end formulas and closed formulas as solutions. They then formed concrete shape for each solution using the chain of signification that was applied for solution by forming procedural similarity. At this time, the chain of signification could be the combination of numbers, words, and pictures (such as diagrams or graphs) or just numbers or words. On the other hand, the student C who recognized closed formulas and her own rule as a solution method could not formulate completely procedural similarity due to many errors arising from number information. Nonetheless, all of the subjects showed something in common in the process of coming up with a algorithm that was semi-open-end formula or closed formula.

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An Investigation on Combustion Characteristics of The Closed Cycle Diesel Engine (폐회로 디젤엔진의 연소특성에 관한 고찰)

  • 박신배
    • Transactions of the Korean Society of Automotive Engineers
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    • v.8 no.6
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    • pp.60-69
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    • 2000
  • In order to obtain underwater or underground power sources, the closed cycle diesel engine is operated in the non air-breathing circuit system where the major species of the working fluid include oxygen, argon, and recycled exhaust gas. In the present study, the closed cycle diesel engine is designed to operate at the intake pressure between 2 and 3 bar. For operating in the open-cycle and closed-cycle situations, experimental apparatus using this diesel engine is made with ACAP as data acquisition system. In open, semi-open, and closed cycle modes, the predicted p-$\theta$ and P-V are compared with load bank power. Computation have been performed for wide range of major experimental parameters such as the specific fuel and oxygen concentrations, fuel conversion efficiency and polytropic exponent, IMEP and maximum cylinder pressure.

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The Effects of Fabrication Conditions on Forging Limitation and Mechanical Property in Semi-Solid Forming Process (반용융 단조공정에 있어서 제조 조건이 성형성과 기계적 성질에 미치는 영향)

  • 정경득;강충길
    • Transactions of Materials Processing
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    • v.10 no.3
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    • pp.214-222
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    • 2001
  • The homogeneous distribution of solid region without liquid segregation is important in terms of high quality component during thixoforming process. In closed die semi-solid forging process, liquid segregation is strongly affected by injection velocity than solid fraction because the material has to travel relatively long distance to fill the cavity through a narrow gate. The designed die by computer simulation data was used to thixoforging process. The thixoforming velocity to prediction the liquid segregation had been determined with strain rate associated with multistage velocity control during compression test of semi-solid material. The optimal forging velocity and die temperature were investigated to produce the near-net-shape compressor component. The mechanical properties of thixoformed component were tested with various die and material temperatures before and after heat treatment.

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