• 한국미생물·생명공학회지
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• 제19권4호
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• pp.398-404
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• 1991

효모를 Na-alginate에 고정화한 후 연속반응기를 이용한 glucose 발효로 에탄올을 생산하였다. 그 결과 고정화 효모의 활성화 시간은 20~25시간이었다. 연속발효에서 고정화효모의 온도안정성은 30~$37^{\circ}C$였으며 pH 안정성은 pH 4.0~pH 8.0, 최적 희석속도는 $0.2h^[-1}$ 이었고 에탄올생산 최적 당농도는 15%였다. 최적조건에서 에탄올수율은 0.23, 생산된 에탄올 농도는 33.90g/l 그리고 에탄올 생산성은 7.12g/$l\cdot h$로 각각 나타났다.

• Agribusiness and Information Management
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• 제11권2호
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• pp.16-24
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• 2019

BRIS has been established by the Ministry of Agriculture, Food and Rural Affairs since 2011 under Article 21 of the Act on the Preservation, Management and Utilization of Agricultural Life Resources. It is an information service that provides information related to agricultural life resources in connection with the Rural Development Administration, the Forest Service, and Korea Seed & Variety Service, Agricultural Resources and Agricultural and Livestock Quarantine Headquarters. The purpose of this study is to evaluate how the users assess the information system quality (information quality, system quality) for the current Bio Resource Information Service (BRIS). Ultimately, the structural equation modeling analyzes the causal relationship between each variable and how it responds to the user's continuous use intention. As a result, information quality among information system quality and information quality among system quality used as the main variables for the evaluation of BRIS were statistically positively influenced by users' perceived usefulness, while system quality It has been analyzed to have a positive effect on the sustained use intention. The user's continuous use intention is positively influenced by the information system quality and perceived usefulness at a statistically significant level. Especially, the perceived usefulness plays a role in mediating the user's continuous use intention.

• 대한안전경영과학회지
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• 제12권2호
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• pp.89-97
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• 2010

The most important concern in the internet service organizations in competitive market circumstances is to focus on formation and maintenance of continuous relationship with customers. The purpose of this study is to verify the effect of perception of the fairness - procedural fairness for recovery, interactional fairness, fairness for reward on customer's satisfaction and trust, behavior when the internet service company failed to service such as disclosure of personal information. This study aims to apply justice theories to service recovery. As a result, first, the customer's perceived justice had a significant effect on the customer satisfaction and trust in service recovery. Second, the customer's satisfaction positive effect on trust. Third, customer's satisfaction formed by service recovery had a effect on the customer's behavior such as continuous usage intention. Therefore, this study was reveal how the extent of justice perception felt by customers in the service recovery process, causes positive causation relationship which affect customer behavior intention.

• Computers and Concrete
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• 제16권3호
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• pp.357-380
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• 2015

In this study, a simple indeterminate strut-tie model which reflects complicated characteristics of the ultimate structural behavior of continuous reinforced concrete deep beams was proposed. In addition, the load distribution ratio, defined as the fraction of applied load transferred by a vertical tie of truss load transfer mechanism, was proposed to help structural designers perform the analysis and design of continuous reinforced concrete deep beams by using the strut-tie model approaches of current design codes. In the determination of the load distribution ratio, a concept of balanced shear reinforcement ratio requiring a simultaneous failure of inclined concrete strut and vertical steel tie was introduced to ensure the ductile shear failure of reinforced concrete deep beams, and the primary design variables including the shear span-to-effective depth ratio, flexural reinforcement ratio, and compressive strength of concrete were reflected upon. To verify the appropriateness of the present study, the ultimate strength of 58 continuous reinforced concrete deep beams tested to shear failure was evaluated by the ACI 318M-11's strut-tie model approach associated with the presented indeterminate strut-tie model and load distribution ratio. The ultimate strength of the continuous deep beams was also estimated by the experimental shear equations, conventional design codes that were based on experimental and theoretical shear strength models, and current strut-tie model design codes. The validity of the proposed strut-tie model and load distribution ratio was examined through the comparison of the strength analysis results classified according to the primary design variables. The present study associated with the indeterminate strut-tie model and load distribution ratio evaluated the ultimate strength of the continuous deep beams fairly well compared with those by other approaches. In addition, the present approach reflected the effects of the primary design variables on the ultimate strength of the continuous deep beams consistently and reasonably. The present study may provide an opportunity to help structural designers conduct the rational and practical strut-tie model design of continuous deep beams.

• 충청수학회지
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• 제28권3호
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• pp.365-375
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• 2015

Of concern is the existence, uniqueness, and continuous dependence of a mild solution of a nonlocal Cauchy problem for a semilinear mixed Volterra-Fredholm functional integrodifferential equation. Our analysis is based on the theory of a strongly continuous semigroup of operators and the Banach fixed point theorem.

• 대한수학회보
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• 제36권4호
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• pp.723-736
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• 1999

The paper is devoted to generalizations of continuity of set-valued mappings and some properties of hypertopologies on the collection of some subsets of a topological space. It is also dedicated to continuous selection theorems without relatively higher separation axioms. More precisely, we give characterizations of $\lambda$-collectionwise normality using continuous functions as in Michael's papers.

• International Journal of Quality Innovation
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• 제3권2호
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• pp.38-45
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• 2002

Continuous quality improvement is now the focus of research and application in quality engineering. To achieve continuous improvement, it's necessary to integrate quality tools and to plan, design and control the whole process of creating quality. Based on the extensive literature review and the philosophy of concurrent quality engineering, the paper analyzes the relationships among major quality tools such as QFD, FMEA, DOE and SPC and presents a basic model and structure for the integration of quality tools.

• 한국표면공학회지
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• 제25권3호
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• pp.117-125
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• 1992

In the electrolysis process of zinc plating impurity ions must be removed from zinc chloride plating solution because it's harmful to the current efficiency and the purity of zinc plating. In this study using zinc ball as a prcipitant instead of zinc dust, the fundamental data for continuous cementation process was studied. Based upon two series of experiments that consist of batch experiment with cylindrical zinc specimen and continuous experiment with zinc balls, following results have been obtained. In the continuous experiment all impurity ions have been removed within 1 hour regardless of various experimental conditions.

• Journal of applied mathematics & informatics
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• 제2권2호
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• pp.83-95
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• 1995

Given a closed subset of the family $S^{*}(\alpha)$ of functions starlike of order $\alpha$, a continuous Frechet differentiable functional J, is constructed with this collection as the solution set to the extremal problem ReJ(f) over $S^{*}(\alpha)$. The support points of $S^{*}(\alpha)$ is completely characterized and shown to coincide with the extreme points of its convex hulls. Given any finite collection of support points of $S^{*}(\alpha)$ a continuous linear functional J, is constructed with this collection as the solution set to the extremal problem ReJ(f) over $S^{*}(\alpha)$.

• 한국산학기술학회논문지
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• 제21권12호
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• pp.120-130
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• 2020

본 연구는 SNS에서 지각된가치(기능적가치, 사회적가치)와 스트레스(복잡성, 불안감)가 지속사용의도에 미치는 영향을 고찰하였다. 특히 본 연구는 SNS 유형이 SNS 지속사용의도에 미치는 직·간접적인 영향을 살펴보고자 하였다. 연구모형은 SNS를 사용하고 있는 461명의 응답자를 대상으로 테스트하였으며, 신뢰도, 타당성, 경로 및 위계적 회귀분석을 수행하기 위해 SPSS 21.0과 PLS 2.0이 사용되었다. 연구결과는 다음과 같다. 첫째, 기능적가치와 사회적가치는 만족에 긍정적인 영향을 미친다. 둘째, 복잡성은 만족에 부정적인 영향을 미친다. 셋째, 불안감과 만족은 지속사용의도에 긍정적인 영향을 미친다. 넷째, SNS 유형은 지속사용의도에 부정적인 영향을 미친다. 다섯째, 불안감과 지속사용의도 간의 관계에서 SNS 유형은 조절효과를 가지는 것으로 나타났다. 특히 불안감은 개방형 SNS 보다 폐쇄형 SNS에서 지속 사용의도에 더 강한 영향을 미쳤다. 이러한 연구결과를 바탕으로 다음과 같은 실무적 시사점을 제시하였다. 첫째, 폐쇄형 SNS의 기업들은 개방형 SNS 사용자들을 유인하는 전략과 사용자 이탈을 방지하는 전략을 동시에 추진해야 할 것이다. 반면에 개방형 SNS의 기업들은 새로운 신규가입자 유치를 위해 노력해야 할 것이다. 둘째, 폐쇄형 SNS의 기업들은 여러 가지 부가 아이템과 시스템적 장치를 제공함으로써 SNS 사용자들이 불안감을 떨치기 위해 노력하여야 할 것이다. 반면에, 개방형 SNS의 기업들은 SNS 사용자들이 충분히 사회적 관계를 잘 유지하고 있다는 메시지를 지속적으로 제공하여야 할 것이다.