• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1990년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 26-27 Oct. 1990
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• pp.523-528
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• 1990

This paper discusses the problem of designing an observation function as coarsest as possible in supervisory control of discrete event dynamic systems. Some algebraic properties of two sets consisting of observation functions for which the given desirable behavior is realizable are investigated:these sets with a partial ordering turn out not to possess largest elements. Two natural methods of obtaining an observation function, which is frequently coarser than the identity mapping, are also presented. An example illustrates the use of these methods.

• 한국막학회:학술대회논문집
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• 한국막학회 1995년도 추계 총회 및 학술발표회
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• pp.22-28
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• 1995

Since the discovery of liquid crystallinity by Reinitzer [1] in 1988 as he studied the melting behavior of cholesteryl benzoate, anisotropic structural ordering in fluid phases has been of considerable interest to chemists, physicists and other scientists. Polymers which exhibit liquid crystallinity either in solution (lyotropic) or in the neat state upon heating (thermotropic) have both theoretical and practical importance [2]. Du Pont's Kevlar, a high modulus polyamide fiber spun from a lyotropic solution, is a prime example of such an application.

• Journal of Magnetics
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• 제15권1호
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• pp.29-31
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• 2010

We studied the magnetic properties of $TmFe_2O_4$. The magnetization measurements revealed the magnetic ordering of Fe spins at around 240 K. The difference between zero-field-cooled (ZFC) and field-cooled (FC) magnetization was close to the thermoremanent magnetization (TRM), indicating the glass behavior exhibited by this material.

• Communications for Statistical Applications and Methods
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• 제20권3호
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• pp.185-191
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• 2013

Kiefer (1961) studied asymptotic behavior of empirical distribution using the law of the iterated logarithm. Robertson and Wright (1974a) discussed whether this type of result would hold for a maximum likelihood estimator of a stochastically ordered distribution function; however, we show that this cannot be achieved. We provide only a partial answer to this problem. The result is applicable to both estimation and testing problems under the restriction of stochastic ordering.

• 한국초전도ㆍ저온공학회논문지
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• 제18권4호
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• pp.1-4
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• 2016

We investigated the relation between the Cu-O bond length and the superconducting properties of $BaSnO_3$ (BSO)-added $GdBa_2Cu_3O_{7-x}$ (GdBCO) thin films by using extended x-ray absorption fine structure (EXAFS) spectroscopy. 4 wt.% $BaSnO_3$ (BSO) added $GdBa_2Cu_3O_{7-x}$ (GdBCO) thin films with varying thickness from $0.2{\mu}m$ to $1.0{\mu}m$ were fabricated by using pulsed laser deposition (PLD) method. The transition temperature ($T_c$) and the residual resistance ratio (RRR) of the GdBCO films increased with increasing thickness up to $0.8{\mu}m$, where the crystalline BSO has the highest peak intensity, and then decreased. This uncommon behaviors of $T_c$ and RRR are likely to be created by the addition of BSO, which may change the ordering of GdBCO atomic bonds. Analysis from the Cu K-edge EXAFS spectroscopy showed an interesting thickness dependence of ordering behavior of BSO-added GdBCO films. It is noticeable that the ordering of Cu-O bond and the transition temperature are found to show opposite behaviors in the thickness dependence. Based on these results, the growth of BSO seemingly have evident effect on the alteration of the local structure of GdBCO film.

• 유통과학연구
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• 제18권9호
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• pp.45-53
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• 2020

Purpose: This study aims at investigating consumers' choice in online food purchasing behavior and the impact on repurchase for fresh food delivery which has recently shown rapid growth in Korea. The study focuses on the user experience factors af fecting satisfaction and intention to continuously use the online food market. Research design, data and methodology: The survey was conducted by 309 people who had purchased fresh food online, and the analysis was conducted using SPSS and AMOS. Structural Equation Modeling was used for the analysis for the verification of hypotheses. The factors that consumers value when ordering fresh food delivery services were defined as system quality, service quality, commodity quality, brand characteristics, and economics from the preceding study and the relationship between satisfaction and willingness to repurchase was verified. Results: When consumers purchase fresh food online, system quality, product quality, brand characteristics, and economics have had a significant impact on satisfaction. Meanwhile, of the five optional attributes of consumers, only economic efficiency has been verified to have a statistically significant impact on repurchase intentions. Conclusions: The results of the study suggested factors that consumers consider important when ordering fresh food online, providing basic data for companies to develop related strategies.

• Bulletin of the Korean Chemical Society
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• 제32권3호
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• pp.939-942
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• 2011

Conductive carbon films were prepared at room temperature by unbalanced magnetron sputtering (UBMS) on silicon substrates using argon (Ar) gas, and the effects of post-annealing temperature on the structural, tribological, and electrical properties of carbon films were investigated. Films were annealed at temperatures ranging from $400^{\circ}C$ to $700^{\circ}C$ in increments of $100^{\circ}C$ using a rapid thermal annealing method by vacuum furnace in vacuum ambient. The increase of annealing temperature contributed to the increase of the ordering and formation of aromatic rings in the carbon film. Consequently, with increasing annealing temperature the tribological properties of sputtered carbon films are deteriorated while the resistivity of carbon films significantly decreased from $4.5{\times}10^{-3}$ to $1.0{\times}10^{-6}\;{\Omega}-cm$ and carrier concentration as well as mobility increased, respectively. This behavior can be explained by the increase of sp2 bonding fraction and ordering $sp^2$ clusters in the carbon networks caused by increasing annealing temperature.

• 가족자원경영과 정책
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• 제6권2호
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• pp.31-52
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• 2002

This study classified consumers' behaviors of purchasing gifts, divided groups by the types of similar behaviors, and examined impacts of demographic variables, relevant variables in purchasing processes on those behaviors. Findings of this study can be summarized as follows. First, factors explaining consumers' behaviors of purchasing gifts were the tendency of demonstrative purchase, the level of placing values to the meaning of gifts, the level of altruism and rationality in the purchase of gifts, and the tendency of impulsive purchase. On the basis of these five factors, five distinct consumer groups showing similar behaviors of purchasing gifts based on the results of Cluster analysis were identified. Those groups were impulsiveㆍdemonstrative groups, impulsiveㆍnon-sincere groups, indifferent groups, non-impulsiveㆍdemonstrative groups, non-altruistic'ㆍrational groups, sincere groups, and altruisticㆍrational groups. Second, behaviors of purchasing gifts showed significant differences depending on gender, educational levels, occupational types, and women's employment status. Consumers with high education, professional occupation, high income tended to show the demonstrative purchase. Male consumers were not interested in the purchases of gifts and placed high values on the meanings of gifts. In contrast, female consumers showed rational behavior, but revealed the tendency of demonstrative in the purchase of gifts as well. Finally, behaviors of purchasing gifts were also different depending on the method of gathering consumer information, places of purchasing gifts, experiences of ordering paid wrapping gifts and the relevant costs, consumers' evaluations of the purchases of gifts, and degrees of satisfaction after the purchase of gifts. Impulsive'ㆍdemonstrative groups and non-impulsive'ㆍ demonstrative groups preferred departments as places of purchasing gifts and choose ordering paid wrapping gifts but showed dissatisfactions after purchases of gifts. Consumers who belongs to non-altruistic'ㆍrational groups, sincere groups, and altruistic'ㆍ rational groups tended to prefer local stores in their own villages as places of purchasing gifts and did not order paid wrapping gifts while showing high after the purchase of gifts.

• 한국주조공학회지
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• 제41권5호
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• pp.445-453
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• 2021

다양한 합금계에 대한 계산열역학은 CALPHAD 기법으로 잘 알려져있다. 실험적으로 측정된 열역학 특성들을 활용하여 각 상에 대한 Gibbs 에너지 모델 파라미터들을 구하여, 주로 실험적으로 측정되지 못한 영역에 대한 예측이나 실험 결과에 대한 열역학 해석에 활용되고 있다. 본 연구에서는 내열 주조 합금 (IN-657)이 장시간 사용 후에 일정 영역에서 파괴되는 현상의 열역학적 해석을 위해 Ni-Cr-Nb-C 사원계 시스템의 열역학 모델링을 수행하였고, Cr 함량에 따른 시스템의 안정상, 온도에 따른 상분율 및 Ni₂Cr상의 long range ordering 파라미터를 계산하였고 실험결과와 비교하였다. 계산된 열역학 물성들은 실험으로 보고된 파괴온도 영역 및 해당 영역에서 생성된 안정상에 대한 결과를 잘 설명한다. CALPHAD 기법을 통한 열역학 모델링은 다양한 주조 합금의 열역학적 거동을 해석하고 예측하는데 유용하게 사용될 수 있을 것으로 기대된다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2009년도 정보 및 제어 심포지움 논문집
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• pp.264-266
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• 2009

A skill is defined as the special ability to do something well, especially as acquired by learning and practice. To learn a skill, a Bayesian network model for representing the skill is first learned. We will regard the Bayesian network for a skill as an affordance. We propose a soft Behavior Motivation(BM) switch as a method for ordering affordances to accomplish a task. Then, a skill is constructed as a combination of an affordance and a soft BM switch. To demonstrate the validity of our proposed method, some experiments were performed with GENIBO(Pet robot) performing a task using skills of Search-a-target-object, Approach-a-target-object, Push-up-in front of -a-target-object.