• 한국기계연구소 소보
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• s.9
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• pp.169-181
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• 1982

This paper presents three methods for ship hull form improvement on the basis of wave pattern analysis. These methods are primarily based on the assumption that a linear relation exists between the small difference of hull sections and the difference of the wave amplitude functions. The improved hull form of ship is made by superposing a thin hull form on that of a parent model. The first method use the simplification of framelines and Michell's Theory to the formula of wave resistance for superposed thin ship. The second method use tent functions and Michell's Theory to that. And the third is experimental method.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10a
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• pp.401-404
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• 1996

A new method for the electrostatic suspension of disk-shaped objects is proposed which is based on a switched-voltage control scheme. It operates according to a relay feedback control and deploys only a single high-voltage power supply capable of delivering a dc voltage of positive and/or negative polarity. In addition to the unique feature that no high-voltage amplifiers are needed, this method provides a remarkable system simplification relative to conventional methods. It is shown that despite the inherent limit cycle property of relay feedback based control, an excellent performance in vibration suppression is attained due to the presence of a relatively large squeeze film damping. In this paper, the functional principle of the switched voltage control scheme, numerical analysis, stator electrode design, and a nonlinear dynamic model of the suspension system are described. Experimental results will be presented for a 4-inch silicon wafer that clearly reveal the capability of the proposed control structure to suspend the wafer stably at an airgap length of 50 .mu.m.

• Computers and Concrete
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• v.9 no.5
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• pp.357-374
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• 2012

The aim of this paper is to develop a procedure able to calculate the long-term stress and strain patterns in modern prestressed composite structures which are largely influenced by creep and shrinkage and whose final static configuration is the result of many phases of loading and restraints conditions. The introduction of equivalent moduli, depending on the viscous and elastic features of materials, can guarantee a significant simplification of the problem presented above. The proposed calculation model has been used to design the "Quattroquercie Viaduct" located on the highway "A3" Salerno-Reggio Calabria, Italy.

• Journal of the Korean Society of Combustion
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• v.20 no.2
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• pp.14-27
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• 2015

Calcination, which represents thermal decomposition of $CaCO_3$, is the key reaction in a cement process. Some reactions including heating-up also take place simultaneously in the calcination reactors. Basic thermal performance and dimensions of the reactors in two cases, which are a rotary kiln wih a four-stage cyclone pre-heater and a simple single rotary kiln, were compared. To employ the heat transfer, mass transfer and reaction rate as well as calcination, one-dimensional modeling was conducted in each case. Some simplification about the reactors was described, however, the reliable Nusselt number and heat transfer coefficients on the reactors were used to make results reliable.

• Journal of Distribution Science
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• v.13 no.2
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• pp.25-33
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• 2015

Purpose - This study aims to disclose the problems of both the government and the logistics industry regarding fourth-party logistics, and to provide various solutions at the level of enterprises as well as the government for the introduction of fourth-party logistics in China. Research design, data, and methodology - This study aims to reveal how a shipping company recognizes the creation of partnerships with fourth-party logistics providers, and it reveals several related implications. Results - Fourth-party logistics organizations can be used to achieve maximum business performance as professional logistics companies by incorporating the benefits of outsourcing and insourcing. Outsourcing logistics services through focusing on core competencies and improving customer service can have financial effects and advantages such as the simplification of labor issues. Conclusions - This study did not investigate Korean enterprises through an empirical analysis and provided fourth-party logistics concepts and promotional plans according to domestic and foreign literature. Further studies shall investigate not only the Korean fourth-party logistics model but also the training of logistics professionals to generate profits for both shippers as well as logistics enterprises.

• 한국디지털정책학회:학술대회논문집
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• 2006.06a
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• pp.113-123
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• 2006

The purpose of this paper is twofold; 1) to evaluate the efforts of participatory government in regulatory reform, 2) to propose the strategies and tasks for future regulatory reform in Korea. An ex-post evaluation model for regulatory performance is applied to process, output, and outcome of the regulatory reform. The results of the evaluation show that there is still room for improvement in many aspects of regulatory reform. While there has been substantial advance in regulatory quality and management, carefully planned strategies are essential for Korean regulatory reform to move to the next stage of regulatory reform. Thus, based on the evaluation, future strategies and tasks for regulatory reform are presented as short-term tasks, mid to long range tasks, and continuous tasks.

• Journal of Information Technology Applications and Management
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• v.15 no.1
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• pp.271-282
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• 2008

Database administrators are demanded to acquire much knowledges and take great efforts for keeping consistent performance in system. Various principles, methods, and tools have been proposed in many studies and commercial products in order to alleviate such burdens on database administrators, and it has resulted to the automation of DBMS which reduces the intervention of database administrator. This paper suggests a resource selection method that estimates the status of the database system based on the workload characteristics and that recommends tuneable resources. Our method tries to simplify selection information on DBMS status using data-mining techniques, enhance the accuracy of the selection model, and recommend tuneable resource. For evaluating the performance of our method, instances are collected in TPC-C and TPC-W workloads, and accuracy are calculated using 10 cross validation method, comparisons are made between our scheme and the method which uses only the classification procedure without any simplification of informations. It is shown that our method has over 90% accuracy and can perform tuneable resource selection.

• International Journal of Advanced Culture Technology
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• v.2 no.1
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• pp.25-29
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• 2014

China and South Korea have effectively reached a free trade agreement. The deal now faces legal and parliament reviews in the two countries. We need to discuss the recommendations on XML conversion with UN / CEFACT electronic documents. To solve this problem of interworking between these standards, Two kinds of translation rules is proposed for exchanging to UN / CEFACT Tag smoothly. For development and distribution of electronic documents to be conformed to international standards, it is enough to have the role of international activities continue to supply part of the domestic industry and the trends in participation and international standard. Our principal focus is on facilitating national and international transactions, through the simplification and harmonization of processes, procedures and information flows, and so contributing to the growth of global commerce. The agreement with South Korea will be China's ninth bilateral FTA.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.30 no.5 s.248
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• pp.488-495
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• 2006

The demand for the use of 3D CAD data over the Internet environment has been increased. However, transmission of 3D CAD data has delayed the communication effectiveness because of the CAD data size. Lightweight CAD file design methodology is required for rapid transmission in the distributed environment. In this paper, to derive lightweight CAD files from commercial CAD systems, a file translation system producing a native file is constructed first by using the InterOp and API of the ACIS kernel. Using the B-rep model and mesh data extracted from the native file, the lightweight CAD file with topological information is constructed as a binary file. Since the lightweight CAD file retains topological information, it is applied to the dimensional verification, digital mock-ups and visualization of CAD files. Effectiveness of the proposed lightweight CAD file is confirmed through various case studies.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.11 no.3
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• pp.154-159
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• 2012

For numerical analysis of the plate heat exchanger, a lot of time are required in modeling work and calculation. Whereas, this paper was purposed to identify characteristic of the plate heat exchanger through simplification of modeling by interpreting the numerical analysis proximity with the actual model. This study was also examined temperature difference between inlet side and outlet side, inner pressure drop, heat transfer area of plate and change of heat transfer coefficient on the plate depending on the inner corrugation angle and corrugation pitch of a herring bon pattern of the plate heat exchanger among chevron types of the plate exchanger.