• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1307-1310
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• 2005

ATM is element that reliability, stability is important in relation with customer by financial agency used device. To embody high reliability and stability, reliability estimation technology development is important. When new product is developed, performance and reliability evaluation of product are essential element. In this paper, is treating contents on reliability estimation of stepping motor, BLDC motor and solenoid that is main driving source of note handling units.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.2019-2023
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• 2005

A aspheric lens is one a key point optical element in the optical industry. The feature of a aspheric lens is not to have the spherical aberration. A aspheric lens is also essential element for high-precision and light-weight in the optical machine. Generally it have been used in a tailor progression an aspheric lens modelling much. In this study we applied a lay back-tracer using a index of refraction to draw a creative aspheric lens. And we executed a comparison experiment for refraction situation of shape and straightness experiment to inspect the drawn aspheric lens in this study

• Transactions of Materials Processing
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• v.7 no.1
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• pp.3-11
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• 1998

During the forming process of sheet metals, the drawbead in the die face controls a restraining force so that the sheet flows into the die cavity with tension. In order to investigate a drawgbead restraining force and a pre-strain just after drawbeads which are essential in the finite element analysis of form-ing processes, the friction test and drawing test are employed. The experiments performed with a cir-cular bead stepped bead double circular bead and circular-and-stepped bead in the various forming conditions and bead sizes show that the restraining force varies linearly with the blank holding force. bead radius blank thickness and friction but the pre-strain nonlinearly does with them.

• Journal of Korean Society of Water and Wastewater
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• v.28 no.4
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• pp.491-500
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• 2014

Due to rapid urbanization and industrialization, water supply and sewer line systems are also developed relevantly. Manhole is an essential component structure of the pipeline system. Manhole is a structure constructed to accommodate the direction, dimension, differences in level, and easy of maintenance in the pipeline system. In this paper we present the result of investigations pertaining to the structural behavior of PVC sewer manhole buried underground. In the paper mechanical properties of PVC material are reported. In addition, by the finite element analysis (FEA), we confirmed that a PVC double-wall corrugated pipe manhole, when it is buried underground, is safe for the stress as well as buckling strength if the manhole is constructed within the suggested limit of buried depth.

• Korean Institute of Interior Design Journal
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• v.13 no.2
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• pp.72-79
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• 2004

First of all corner is an essential element to consist the space, but there is not much solid study and basic concept on the corner. The most important reason is the lack of the concept on the corner. The definition of corner by itself carries the term of space. Accordingly arguing the corner in space is to characterize the space. The corner is an important element to build up the space. The purpose of this study is to give a definition on the comer in space and suggest the way of practical use. The corner in space began to transform after Cubism. Therefore this study is bounded after Cubism era. The focus of study on plastical expression properties is on the view point by each era and constitutional point of view. In conclusion, the concept of corner has been switched from the concept of structure to concept of decoration. Also, study found that the concept of corner has the ideology, medium, and characteristics of boundary.

• The Transactions of the Korea Information Processing Society
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• v.7 no.9
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• pp.2913-2919
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• 2000

It is essential to get large prime numbers in the design of asymmetric encryption algorithm. However, the pseudoprime numbers with high possibility to be primes have been generally used in the asymmetric encryption algorithms, because it is very difficult to find large deterministic prime numbers. In this paper, we propose a new method of deterministic prime number generation. The prime numbers generated by the proposed method have a 100% precise prime characteristic. They are also guaranteed reliability, security strength, and an ability of primitive element generation.

• Journal of Electrical Engineering and Technology
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• v.12 no.4
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• pp.1548-1555
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• 2017

This paper attempts to employ and investigate neural based approaches as interpolation tools for modeling of Switched Reluctance Motor (SRM) drive. Precise modeling of SRM is essential to analyse the performance of control strategies for variable speed drive application. In this work the suitability of Generalized Regression Neural Network (GRNN) and Extreme Learning Machine (ELM) in addition to conventional neural network are explored for improving the modeling accuracy of SRM. The neural structures are trained with the data obtained by modeling of SRM using Finite Element Analysis (FEA) and the trained neural network is incorporated in the model of SRM drive. The results signify the modeling accuracy with GRNN model. The closed loop drive simulation is performed in MATLAB/Simulink environment and the closeness of the results in comparison with the experimental prototype validates the modeling approach.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2005.10a
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• pp.3-9
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• 2005

The recent notion of Network Centric Warfare (NCW) emphasizes the ability to distribute right information at the right time to maximize the combat effectiveness. Accordingly, in the modern combat system the importance of non-physical element, such as communication system is increasing. However, an NCW-support communication network system is expensive. Therefore, it is essential to develop a proper combat system evaluation method to establish an efficient NCW-support combat system. Traditionally, combat system effectiveness is measured in terms of physical elements such as men and fire power. Obviously, such method is hardly applicable to a modern combat system To overcome this difficulty, we propose an evaluation model based on CA (Cellular Automata) simulation. A set of preliminary combat simulations show that CA simulation may be promising in evaluating non-physical element of a modem combat system.

• Journal of Urban Science
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• v.7 no.1
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• pp.55-61
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• 2018

Long bridges, such as suspension bridges and diagonal bridges, are complex phenomena that show different behaviors depending on the shape and rigidity of the cross sections, such as wind vibrations and liquid vibrations from earthquakes in liquid storage containers. This is called the lower skirt on the lower side of the bridge, and the installation of lower skirt is effective for release and vortex vibrations caused by rapid winds, and that increases the stability of the wind resistance of the bridge. Optimal shape and installation of the lower skirt is also essential to make maximum wind speed effect of the lower skirt. Therefore, this study proposes a numerical analysis method to control the vibration of a bridge by calculating the optimal installation angle of an optimal lower skirt according to the optimal control theory and this study evaluates the impact on the optimal control system by minimizing the dominance equation with an evaluation function,which is an indicator for evaluating the optimal control theory state.

• Journal of Korean Society on Water Environment
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• v.25 no.5
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• pp.651-660
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• 2009

Detailed flow analysis in river is essential to increase the accuracy of water quality simulation since flow variation depends on many factors such as cross sections, channel slopes, and bed materials. In the QUAL2E stream water quality simulation model, the hydraulic coefficients are assigned to the reach that is collection of computational element using the hydraulic coefficient. This study developed a module that can incorporate the results of non-uniform flow analysis and assign such information to each individual element. Model application focused on the upstream of the Hoengseong reservoir including the reservoir where significant flow change is expected. Comparing with original QUAL2E model the developed module improved the result of water quality simulation without considering the relation of flow velocity and flow depth in terms of flow rates.