• Title/Summary/Keyword: 화란

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The Effects of Customer Based Planned Obsolescence on Replacement Purchase Intention -The Moderating Role of Consumer Innovativeness Focus- (소비자관점에서 계획적 진부화가 스마트폰 교체의도에 미치는 영향 -소비자 혁신성의 조절효과를 중심으로-)

  • Byun, Chung-Gyu;Sung, Chang-Soo
    • Management & Information Systems Review
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    • v.36 no.1
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    • pp.143-159
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    • 2017
  • The purpose of this study examined the relationships between planned obsolescence and replacement purchase intention. This study also analyze the moderating effect of consumer innovativeness use on the relationship of planned obsolescence and replacement purchase intention. From total 205 survey analysis, this study finds the positive relationship planned obsolescence and replacement purchase intention. The result of analysis indicated that the functional obsolescence had positive effects on replacement purchase intention. The result of analysis indicated that the economic obsolescence had positive effects on replacement purchase intention. The result of analysis indicated that the psychological obsolescence had positive effects on replacement purchase intention. The result also shows that consumer innovativeness had a moderating effect on the relationship between planned obsolescence and replacement purchase intention. Finally, this study concluded with a discussion of the implications of the research findings and directions for future research.

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Continuous Production of Fructooligosaccharides from Sucrose by a Dual Immobilized Enzyme System of Fructosyltransferase and Glucose Isomerase (과당전이효소와 포도당 이성화 효소의 고정화 혼합효소계에 의한 설탕으로부터 프락토올리고당의 연속생산)

  • 윤종원;서근학송승구
    • KSBB Journal
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    • v.10 no.1
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    • pp.9-14
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    • 1995
  • Continuous production of fructooligosaccharides from sucrose by a dual immobilized enzyme system of fructosyltransferase and glucose isomerase was studied in a column reactor. The optimal temperature and pH of the immobilized fructosyltransferase were $65^{\circ}C$ and 5.5, respectively. The activity of glucose isomerase was favorable as temperature and pH were increased within the ranges examined. However, both the immobilized enzymes were thermally unstable over $5^{\circ}C$, suggesting that long-term operation of the dual immobilized enzyme column should be carried out below $50^{\circ}C$. The optimum packing ratio of fructosyltransferase to glucose isomerase was found to be around 5/3. Under the optimized reaction conditions, the dual enzyme column was successfully operated for 40 days without any loss of initial enzyme activities, yielding 66% of fructooligosaccharides. Furthermore, the relative sweetness of fructooligosaccharides produced by a dual emzyme system was enhanced by 6% compared with that of fructosyltransferase alone.

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Gasification and Methanation Characteristics for SNG(Substitute Natural Gas) from Coal Char (석탄촤로부터 대체천연가스(SNG)를 얻기 위한 가스화 및 메탄화 반응 특성)

  • Kim, Su-Hyun;Kim, Mun-Hyun;Kim, Na-Rang;Kim, Hyung-Taek;Yoo, Young-Don
    • 한국신재생에너지학회:학술대회논문집
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    • 2008.05a
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    • pp.345-348
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    • 2008
  • 본 연구에서는 가스화 반응, 수성가스 전환 반응, 메탄화 반응 등으로 구성된 SNG제조 공정에 대한 해석을 통해, 석탄 촤의 가스화 반응에 의해 생성된 합성가스를 이용한SNG제조 공정 특성을 파악하고자 하였고, SNG제조 공정 중 가스화 공정에 대한 실험을 통해 가스화 공정의 조건에 따른 합성가스 발생 특성 및 메탄화 반응의 특성을 살펴보았다. 석탄 촤를 대상으로 하여 가스화 공정의 $O_2$/feed ratio와 steam/feed ratio 조건 변화에 따른 합성가스 발생 특성을 살펴본 결과 steam을 투입하지 않은 경우 발생되는 합성가스 중 CO의 농도는 55$\sim$65%, $H_2$ 9$\sim$11%, $CO_2$ 24$\sim$29% 범위였고, $O_2$/feed ratio가 증가할수록 CO의 농도는 증가하고, $H_2$$CO_2$의 농도는 감소하는 경향을 나타내었다. 또한,steam을 투입하는 경우 합성가스 중 CO의 농도는 20$\sim$37%, $H_2$ 16$\sim$18%, $CO_2$ 42$\sim$55% 범위였다. 메탄화 공정 해석 결과 메탄의 농도를 최대로 얻을 수 있는 조건은 $H_2$/CO 비가 3인 조건이었고 온도가 낮을 수록 생성농도가 높아짐을 알 수 있었다. 가스화 특성 실험 결과 및 공정해석 결과, 메탄화 반응에 대한 실험 및 공정해석 결과는 고체시료의 가스화 반응을 통해 발생한 합성가스를 이용한 SNG 제조 공정 특성 파악 및 SNG를 제조하기 위해 필요한 단위 공정에 대한 설계 자료 및 운전조건을 결정할 수 있는 주요 인자로 활용될 수 있을 것으로 판단된다.

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A blocking artifacts reduction algorithm using block boundary pixel difference characteristics (블록 경계 화소차값의 특성을 이용한 블록화 현상 제거 알고리즘)

  • 채병조;손채봉;오승준
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.23 no.5
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    • pp.1299-1309
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    • 1998
  • In this paper, we propose a new approach for reducing the blocking artifact that is one of drawbacks of the block-based Discrete Cosine Transform (DCT) without introducing additional information or significant blurring. We modify the inter-block discontinuity minimization technique to preserve edges within a block as well as to reduce visible block boundaries. The homogeneity of each block is decided by the threshold value reated to Q-factor, which is included in a JPEG as well as MPEG streams. The quantization error is estimated by minimizing the discontinuity, which is weighted in proportion to block discontinuity and added to each pixel in the block to compensate block artifacts. The proposed algorithm reconstructs images which have less noticeable block boundaries from a subjective viewpoit without anyconstraints.

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Study on the Hydrogenation and Isomerization Reaction of Dimethylcyclopentadiene (디메틸시클로펜타디엔의 수소화 및 이성화반응 연구)

  • Jeong, Byung Hun;Han, Jeong Sik;Lee, Jeong Ho;Kim, Seong Bo;Lee, Bum Jae
    • Korean Chemical Engineering Research
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    • v.43 no.5
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    • pp.566-570
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    • 2005
  • The study on the hydrogenation and isomerization of unsaturated bicyclic hydrcarbon compounds using methylcyclopentadiene dimer (MCPD) was carried out. Exo compound was prepared through isomerization reaction after two hydrogenation reaction steps. In the first hydrogenation reaction which needs one mole of hydrogen, the formation rate of monomer was increased as dimer was decomposed at reaction temperature above $100^{\circ}C$. At first hydrogenation, DHDMCPD [dihydrodi(methylcyclopentadiene)] was formed and second hydrogenation was proceeded to produce THDMCPD [tetrahydrodi(methylcyclopentadiene)], the ratio of exo to endo THDMCPD was varied by the control of 2nd hydrogenation temperature. To improve the process, continuous 1st and 2nd hydrogenation conditions were established by using the 2nd stage heat controllable reactor. Also, catalytic activities were compared by the use of halogenized aluminum, metal halides and solid acids catalysts on the isomerization reaction from endo to exo THDMCPD.

A Synchronized Multiplexing Scheme for Multi-view HD Video Transport System over IP Networks (실시간 다시점 고화질 비디오 전송 시스템을 위한 동기화된 다중화 기법)

  • Kim, Jong-Ryool;Kim, Jong-Won
    • Journal of Broadcast Engineering
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    • v.13 no.6
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    • pp.930-940
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    • 2008
  • This paper proposes a prototype realization of multi-view HD video transport system with synchronized multiplexing over IP networks. The proposed synchronized multiplexing considers the synchronization during video acquisition and the multiplexing for the interactive view-selection during transport. For the synchronized acquisition from multiple HDV camcorders through IEEE 1394 interface, we estimate the timeline differences among MPEG-2 compressed video streams by using global time of network between the cameras and a server and correct timelines of video streams by changing the time stamp of the MPEG-2 system stream. Also, we multiplex a selected number of acquired HD views at the MPEG-2 TS (transport stream) level for the interactive view-selection during transport. Thus, with the proposed synchronized multiplexing scheme, we can display synchronized HD view.

An Influence of Visualization on Geometric Problem Solving in the Elementary Mathematics (시각화가 초등기하문제해결에 미치는 영향)

  • Yun, Yea-Joo;Kang, Sin-Po;Kim, Sung-Joon
    • Journal of the Korean School Mathematics Society
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    • v.13 no.4
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    • pp.655-678
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    • 2010
  • In the elementary mathematics, geometric education emphasize spatial sense and understandings of figures through development of intuitions in space. Especially space visualization is one of the factors which try conclusion with geometric problem solving. But studies about space visualization are limited to middle school geometric education, studies in elementary level haven't been done until now. Namely, discussions about elementary students' space visualization process and methods in plane or space figures is deficient in relation to geometric problem solving. This paper examines these aspects, especially in relation to plane and space problem solving in elementary levels. First, we investigate visualization methods for plane problem solving and space problem solving respectively, and analyse in diagram form how progress understanding of figures and visualization process. Next, we derive constituent factor on visualization process, and make a check errors which represented by difficulties in visualization process. Through these analysis, this paper aims at deriving an influence of visualization on geometric problem solving in the elementary mathematics.

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Evaluation of Response Functions for Activation Foil-based Bonner Spheres (중성자 방사화 포일 기반 보너구 반응함수 계산 방법)

  • Kim, Jung-Ho;Park, Hyeon-Seo
    • Journal of Radiation Protection and Research
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    • v.36 no.1
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    • pp.44-51
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    • 2011
  • Activation foil-based Bonner sphere spheres are used to obtain neutron energy spectra of nuclear power plants or accelerator-produced neutrons. The position and the foil mass dependence of response functions should be studied carefully before measurement of Bonner spheres. This study showed that the normal incidence to the foil surface made a large shift of responses while parallel and isotropic incidence made no position dependence. The correlation between foil mass and response was not linear. Therefore, the response functions of activation-foil based Bonner spheres should be calculated for every different foil mass and the direction of Bonner spheres for parallel incidence will be preferred for radioactive neutron source or accelerator target produced neutrons.

The Study of poly-Si Eilm Crystallized on a Mo substrate for a thin film device Application (박막소자응용을 위한 Mo 기판 위에 고온결정화된 poly-Si 박막연구)

  • 김도영;서창기;심명석;김치형;이준신
    • Journal of the Korean Vacuum Society
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    • v.12 no.2
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    • pp.130-135
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    • 2003
  • Polycrystalline silicon thin films have been used for low cost thin film device application. However, it was very difficult to fabricate high performance poly-Si at a temperature lower than $600^{\circ}C$ for glass substrate because the crystallization process technologies like conventional solid phase crystallization (SPC) require the number of high temperature (600-$1000^{\circ}C$) process. The objective of this paper is to grow poly-Si on flexible substrate using a rapid thermal crystallization (RTC) of amorphous silicon (a-Si) layer and make the high temperature process possible on molybdenum substrate. For the high temperature poly-Si growth, we deposited the a-Si film on the molybdenum sheet having a thickness of 150 $\mu\textrm{m}$ as flexible and low cost substrate. For crystallization, the heat treatment was performed in a RTA system. The experimental results show the grain size larger than 0.5 $\mu\textrm{m}$ and conductivity of $10^{-5}$ S/cm. The a-Si was crystallized at $1050^{\circ}C$ within 3min and improved crystal volume fraction of 92 % by RTA. We have successfully achieved a field effect mobility over 67 $\textrm{cm}^2$/Vs.

A strategy for effectively applying a control flow obfuscation to programs (제어 흐름 난독화를 효과적으로 수행하기 위한 전략)

  • Kim, Jung-Il;Lee, Eun-Joo
    • Journal of the Korea Society of Computer and Information
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    • v.16 no.6
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    • pp.41-50
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    • 2011
  • Code obfuscation has been proposed to protect codes in a program from malicious software reverse engineering. It converts a program into an equivalent one that is more difficult to understand the program. Code obfuscation has been classified into various obfuscation technique such as layout, data, control, by obfuscating goals. In those obfuscation techniques, control obfuscation is intended to complicate the control flow in a program to protect abstract information of control flow. For protecting control flow in a program, various control obfuscation transformation techniques have been proposed. However, strategies for effectively applying a control flow obfuscation to program have not been proposed yet. In this paper, we proposed a obfuscation strategy that effectively applies a control flow obfuscation transformation to a program. We conducted experiment to show that the proposed obfuscation strategy is useful for applying a control flow transformation to a program.