• Proceedings of the KIEE Conference
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• 1994.07a
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• pp.606-608
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• 1994

This paper presents a low speed (1m/sec) elevator controller with a IGBT inverter (9.5KW). The major engineering problems of this development are noise suppression, thermal-dissipation and reliability improvement. The characteristic marks of this elevator are a single board controller, 40% reduced component, 40% reduced cubic content, EMI filter, vector controlled IGBT inverter.

• 한국정보통신설비학회:학술대회논문집
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• 2007.08a
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• pp.64-68
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• 2007

Commercial WiBro and 3G HSDPA services are launched last year in order to provide high speed wireless Internet access and multimedia service. Currently mobile communication service providers concentrate on the deployment of indoor mobile network since indoor traffic is remarkably increased. For fine indoor wireless communication, an installation of access point system via Public IP network which is called Femtocell is required. The development of indoor Femtocell system must be considered in the viewpoint of low hardware complexity, cost reduction, interlocking with WiBro/HSDPA network without change of network component and easy element management. In this paper, we review the implementation issue and technology of dual mode AP which provides WiBro and HSDPA signal to the user simultaneously. Especially, we describe on the HSDPA Femtocell standardization status and possible 3 types of HSDPA communication module development design. Furthermore we analyze the merits and demerits of each HSDPA Femtocell design type and propose a system which enables handover between indoor HSDPA Femtocell and outdoor commercial HSDPA mobile network.

• Journal of KIISE:Software and Applications
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• v.29 no.12
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• pp.895-906
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• 2002

Due to increased concern about the distributed web application, the interest in EJB - server-side Java component architecture that enables to make out Business Logic without writing codes related to complicated distributed framework - is also increasing. Despite of these increased interest, However, efforts for reliability of these systems have been insufficient. Thus, in this paper, we propose specification technique for applying DbC approach, which can elevate the reliability of software in the Object-Oriented system development, in writing formal specification of EJB-based application. Through this specification technique, developers can gain reliability in the EJB-based application development.

• The Journal of the Korea Contents Association
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• v.10 no.7
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• pp.149-158
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• 2010

This study is a comparative analysis of the creation and development of visual techniques used in girls' comics in the paradigmatic low and high-context cultures of American and Japan. As previous analyses have shown, there are qualitative differences in the expressive mechanisms employed in girls' comics in Eastern and Western cultures, and it is an investigation of this realm of expression that is the basis of this study. Particular emphasis is placed on an analysis of the structure of frames, one of the most fundamental expressive mechanisms in girls' comics. A close examination of this underlying structural component reveals that both cultures demonstrate autonomous growth, providing a theoretical framework for future studies.

• Design & Manufacturing
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• v.14 no.2
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• pp.49-55
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• 2020

Recently, when a new component of construction equipment is designed, a stamping process capable of producing parts having high appearance quality and precision has been gaining attention. However, in general, as it is developed based on existing parts made by welding metal sheets and tubes, frequent to die modification occurs, which increases the time and cost of developing new parts. Thus, it is necessary to reduce the cost by shortening the die development period. In this study, a stamping process was designed for the urea tank cover, which is a part for excavators, to reduce the die development period through sheet metal forming analysis. The stamping process was designed by determining the blank holding force after selecting the initial blank shape and size. The round value at the corner was modified such that formability is ensured. After selecting process parameters, the thickness reduction rate and spring-back effect were reviewed.

• Journal of Engineering Education Research
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• v.6 no.2
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• pp.30-37
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• 2003

This paper presents web-based contents for studying electrical machines using Java Bean and Flash. The component-based software development techniques have been used to develop Java Bean and Flash components which are simple and convenient for learners. The components have been used to make 61 contents for the electrical machines. The contents have highly interactive capability, which gives much interest to learners. The learners can easily understand the electro-mechanical concept by changing the parameters interactively. The class load of the lecture can be reduced because the basic explanation of the subject is replaced by the web contents. The better quality of the class is expected by dealing with the higher concept in the classroom lecture because the basic concepts are explained through the contents.

• Computers and Concrete
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• v.26 no.2
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• pp.175-183
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• 2020

Fly ash has become an important component of concrete as supplementary cementitious material with the development of concrete technology. To make use of fly ash efficiently, four types of fly ash with particle size distributions that are in conformity with four functions, namely, S.Tsivilis, Andersen, Normal and F distribution, respectively, were prepared. The four particle size distributions as functions of the strength and pore structure of concrete were thereafter constructed and investigated. The results showed that the compressive and flexural strength of concrete with the fly ash that conforming to S.Tsivilis, Normal, F distribution increased by 5-10 MPa and 1-2 MPa, respectively, compared to the reference sample at 28 d. The pore structure of the concrete was improved, in which the total porosity of concrete decreased by 2-5% at 28 d. With regarding to the fly ash with Andersen distribution, it was however not conducive to the strength development of concrete. Regression model based on the grey multiple linear regression theory was proved to be efficient to predict the strength of concrete, according to the characteristic parameters of particle size and pore structure of the fly ash.

• Nutrition Research and Practice
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• v.10 no.4
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• pp.424-432
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• 2016

BACKGROUND/OBJECTIVES: Most consumers are able to recognize allergenic foods. However, the frequency of checking such foods is reportedly low, resulting in higher prevalence of food-related allergic reactions in Korea compared to other countries. Thus, this study was performed to investigate the overall perception of allergenic food labeling and its practice level in food manufacturing company employees. SUBJECTS/METHODS: The survey was administered to food safety employees and food development teams at food companies located in metropolitan areas. A total of 399 (93.8%) valid samples were used in the final analysis. Statistical analyses, including Frequency Analysis, t-test, Anova, PCA (Principal Component Analysis), and Pearson Correlation Analysis using SPSS ver. 21.0, were performed. RESULTS: The correct answer rate in the analysis of allergy-related knowledge level ranged from 15.0% to 89.7%. Analysis of differences in allergy-related perception by knowledge level showed significant differences in introduction of a food recall system, strengthening of relevant laws and regulations, content labeling, description of substitutional food, and differentiated package by age. CONCLUSIONS: It can be concluded that labeling of allergenic foods should be made easier and more convenient for checking by employees, developers, and consumers, and it is necessary to provide contents through the development of publicity, guidelines, or APP along with labeling.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2005.11a
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• pp.375-383
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• 2005

The present paper describes the first development of a LOX/kerosene type turbopump in Korea. The liquid rocket engine, that the turbopump can be applied to, has a 30-ton(metric) level of vacuum thrust and employs a gas generator cycle. The turbopump consists of two single-stage centrifugal pumps, that is, LOX and kerosene pumps, and one single-stage impulse turbine. Inter-propellant seal(IPS) is located between the LOX pump and the kerosene pump to avoid any interaction between the propellants. A series of component and TPU(Turbopump Unit) test has been completed in the level of simulant propellants and ready for hot firing tests.

• Journal of the Korea Computer Industry Society
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• v.2 no.3
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• pp.397-406
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• 2001

According to e-business has been used commonly, many companies do e-business deal for B2B, B2C, etc based on internet. To support web-based e-business, companies must construct the homepage and shopping-mall that is able to advertise a publicity work about their companies to customer. In this paper, we classified the components used in the homepage and shopping-mall development about e-business and designed a management system for supporting environment that is searched, updated, edited, etc. For an application example, we analyzed a purchasing process of products by domain analysis and abstracted the components needed. Because this component management system manages components efficiently, it will come in pretty handy in web-based system development.