• Kyungpook Mathematical Journal
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• v.45 no.4
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• pp.539-547
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• 2005

The class of b-open sets in the sense of $Andrijevi{\acute{c}}$ ([3]), was discussed by El-Atik ([9]) under the name of ${\gamma}-open$ sets. This class is closed under arbitrary union. The aim of this paper is to use ${\Lambda}-sets$ and ${\vee}-sets$ due to Maki ([15]) some topologies are constructed with the concept of b-open sets. $b-{\Lambda}-sets,\;b-{\vee}-sets$ are the basic concepts introduced and investigated. Moreover, several types of near continuous function based on $b-{\Lambda}-sets,\;b-{\vee}-sets$ are constructed and studied.

• Tribology and Lubricants
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• v.25 no.1
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• pp.38-42
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• 2009

Gear is an essential component of an automotive. Crowning is used for tooth modification of a gear. The basic concept of gear tooth crowning is to reduce the stress concentration in edge of contact area and appropriate profile modifications can help gears to resist scoring, pitting, and tooth breakage. In this study, a method to determinate spur gear tooth crowning amount to make smooth surface stress and subsurface stress distribution is proposed. This method is based on the contact analysis.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.261.1-261.1
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• 2013

Well-aligned nanowire arrays can be used as building blocks for nanoscale device. Recently, we reported that well-aligned single-crystal organic nanowires has been created by using a direct printing method which is named liquid-bridge mediated nanotransfer molding (LB-nTM). Moreover, multi-layering nanostructures can be fabricated by repeating this printing process. As a result, it is possible to make simple and basic concept of heterojunction devices such as crossed nanowire devices. We fabricated crossed single-crystal organic nanowires nanojunction devices from 6,13-bis (triisopropylsilylethynyl) pentacene (TIPS-PEN) and fullerene (C60) single-crystal nanowires using by direct printing method in solution process. Crossed TIPSPEN/ C60 single-crystal nanowires diode has rectifying behavior with on/off ratios of ~13. In addition, the device shows photodiode characteristics as well as rectification. Our study represent methodology of heterojunction devices using single-crystal nanowires, thereby provide a new direction of future nanoelectronics.

• Journal of Korean Society on Water Environment
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• v.23 no.4
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• pp.429-433
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• 2007

Many researchers have made a study of NPS unit-loads and the scientific evaluation method which need for formulating and enforcing a Total Maximum Daily Load (TMDL) management system and modifying a pollutant discharge loadings function. Some showed the event mean concentration (EMC) on single land-use. For the most parts, as the results showed on multiple land-uses, those cannot be used for NPS unit-loads calculation. NPS runoff shows various phenomena depending on rainfall monitoring data, therefore sampling methods and frequency for NPS monitoring must be different from the general monitoring for water quality trend assessment.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.5
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• pp.32-37
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• 2004

Polishing processes are widely used in the glass, optical, die and semiconductor industries. Chemical Mechanical Polishing (CMP) especially is becoming one of the most important ULSI processes for the 0.25m generation and beyond. CMP is conventionally carried out using abrasive slurry and a polishing pad. But the surface of the pad has irregular pores, so there is non-uniformity of slurry flow and of contact area between wafer and the pad, and glazing occurs on the surface of the pad. This paper introduces the basic concept and fabrication technique of the next generation CMP pad using micro-molding method to obtain uniform protrusions and pores on the pad surface.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.5
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• pp.64-72
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• 2004

An extension of interaction matrix formulation to the problem of system and disturbance identification for a plant that is corrupted by both process and output disturbances is presented. The teaming control develops controllers that learn to improve their performance at executing a given task, based on experience performing this task. The simplest forms of loaming control are based on the same concept as integral control, but operating in the domain of the repetitions of the task. This paper studies the use of such controllers in a decentralized system, such as a robot moving on the vertical plane with the controller for each link acting independently. The basic result of the paper is to show that stability and iterative precision of the learning controllers for all subsystems when the coupling between subsystems is turned off, assures stability of the decentralized teaming in the coupled system, provided that the sample time in the digital teaming controller is sufficiently short. The methods of teaming system are shown up for the iterative precision of each link.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.29 no.1 s.232
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• pp.22-29
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• 2005

A material cloud method, which is a new topology optimization method, is presented. In MCM, an optimal structure can be found out by manipulating sizes and positions of material clouds, which are lumps of material with specified properties. A numerical analysis for a specific distribution of material clouds is carried out using fixed background finite element mesh. Optimal material distribution can be element-wisely extracted from material clouds' distribution. In MCM, an expansion-reduction procedure of design domain for finding out better optimal solution can be naturally realized. Also the convergence of material distribution is faster and well-defined material distribution with fewer intermediate densities can be obtained. In addition, the control of minimum-member sizes in the material distribution can be realized to some extent. In this paper, basic concept of MCM is introduced, and formulation and optimization results of MCM are compared with those of the traditional density distribution method(DDM).

• Asia pacific journal of information systems
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• v.11 no.4
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• pp.99-111
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• 2001

The prediction of stock price index is a very difficult problem because of the complexity of stock market data. It has been studied by a number of researchers since they strongly affect other economic and financial parameters. The movement of stock price index has a series of change points due to the strategies of institutional investors. This study presents a two-stage forecasting model of stock price index using change-point detection and artificial neural networks. The basic concept of this proposed model is to obtain intervals divided by change points, to identify them as change-point groups, and to use them in stock price index forecasting. First, the proposed model tries to detect successive change points in stock price index. Then, the model forecasts the change-point group with the backpropagation neural network(BPN). Finally, the model forecasts the output with BPN. This study then examines the predictability of the integrated neural network model for stock price index forecasting using change-point detection.

• Asia pacific journal of information systems
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• v.1 no.1
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• pp.31-47
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• 1991

The purpose of this study is to assess and develop effective MIS planning method by applying the CSF method. With the comparative analysis of the Rockart's basic concept of CSF and the examples of the corporations which employed CSF methodology, a new CSF method more suitable to Korean business environment is proposed and applied to another company for evaluation. The new CSF methodology consists of three steps. The first step is to preexamine the business conditions. The second step contains an Introductory Workshop, interview with the managers, survey questionnaire, Focusing Workshop, and decision of the priorities for system development. The third step is a real development of an information system out of the first and second steps. As a result of this study, it is found that revised CSF method can induce top management to participate more in the activities of information system development and that it can make top management to focus on the critical area. The fulfillment of the information requirement out of the enhanced MIS planning will lead to more successful management activities.

• Journal of the Korean Society of Industry Convergence
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• v.5 no.4
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• pp.339-346
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• 2002

As characteristic of construction industries, the Issues of construction management have been pointed out because of time and space limit among construction project participants (owner, supervisor, builder, experiment specialty institute, specialty construction company, material supplier and equipment supplier). To improve these issues, procurement system has been introduced by using internet and intranet. Procurement system that was developed by some of large construction companies was considered only internal supply on closed system method. They also restricted to article supply as supply concept. In this paper, we suggest a plan to establish integrated construction procurement system that expands to the article, service and construction work supplies by utilizing the bi-directional and real-time contact system and presents related following research program.