• Journal of the Semiconductor & Display Technology
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• v.7 no.4
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• pp.23-28
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• 2008

A high speed automated pitch variation unit (HAPU) related to semiconductor category sorting movement of the test handler system was developed. In the design process, 'DMADOV' step of 6-Sigma method has been applied. The design result for the desirable pitch variation was a 3:1 reduction rack-pinion and a linkage which are operated by servomotors. The realization and reliability of the mechanism was obtained at the design stage by FEM analysis, and by robust design using Taguchi orthogonal array against weight and deformation. Finally, the validity of the high speed variation mechanism was confirmed via inspection using a high speed camera while performing pitch variation.

• Journal of the Korean Society of Mechanical Technology
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• v.13 no.3
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• pp.73-79
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• 2011

In this study, an analytical realization of end-milling system was introduced using recursive parametric modeling analysis. Also, the numerical mode analysis of end-milling system with different conditions was performed systematically. In this regard, a recursive least square modelling algorithm and the natural mode for real part and imaginary one was discussed. This recursive approach (RLSM) can be adopted for on-line end-milling identification. After experimental practice of the end-milling, the end-milling force was obtained and it was used for the calculation of FRF (Frequency response function) and mode analysis. Also the FRF was analysed for the prediction of a end-milling system using recursive algorithm.

• Spatial Information Research
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• v.15 no.1
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• pp.1-14
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• 2007

u-City is a new concept and phenomena of applying Information & Communications Technology(ICT) into real cities in Korea. In order to effectively integrate a city with high-tech ICT infrastructure, cutting-edge ICT is being integrated into physical urban environments from the planning and construction stage of a city. There are positive expectations regarding its effect on urban planning and citizens' lives. However, construction of u-city has technical limitations as well as institutional obstacles. This paper aims at identifying problems of current u-city practices and suggesting appropriate solutions for those problems. To do so, it first collects opinions from diverse experts. Then, it draws problems and suggests solutions in terms of u-infrastructure, u-service, policy and implementation process.

• Journal of the Korean Society for Railway
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• v.10 no.4
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• pp.393-397
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• 2007

During the complex systems development, a great deal of data are generated from both the systems engineering process and project management process, and also some data are required to be prepared for the system engineering management plan (SEMP). For the successful completion of the project, it is necessary to effectively manage all the data in order to maintain data consistency and traceability. To fulfill the necessity, this paper introduces the concept of an integrated data architecture and discusses its realization with $Cradle^{(R)}$(a computer aided systems engineering tool). Also, it was described how to automate the production of the SEMP in that working environment. The result of the approach, managing complex data efficiently in the systems engineering view, has been successfully applied in the Railway Safety Development Program.

• Proceedings of the KIEE Conference
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• 1989.07a
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• pp.138-141
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• 1989

In resent years, aided by the power and capability of digital computation, the techniques of Walsh Transform have been exploited for applications in commun- ication and signal processing. This paper presents an approach of FWT by using a 16- bit word-length micro- computer. This FWT implements an in-placed decimation-in-sequency algorithm which improves processing speed and memory storage. Several examples illustrate the process and demonstrate the power spectrum of FWT and that of FFT for the waveforms

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.475-475
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• 2014

Dye sensitized solar cells (DSSCs) are regarded as potential inexpensive alternatives to conventional solid-state devices. The flexible version, employing conductive-plastic-film substrates, is appealing for commercialization of DSSCs because it not only reduces the weight and cost of the device but also extends their applications. However, the need for high temperature does not permit the use of plastic-film substrate. So, development of low-temperature methods is therefore realization of flexible DSSCs. In this work, the electrophoretic deposition combined with hydrothermal treatment was employed to prepare nanocrystalline $TiO_2$ thin film at low temperature. We confirmed the prepared $TiO_2$ thin films with different voltages and deposition times in the electrophoretic deposition process. Properties of the $TiO_2$ films were investigated by various analysis method such as X-ray diffraction, field emission scanning electron microscopy (FESEM) and UV-visible spectrophotometer.

• KIEAE Journal
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• v.11 no.6
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• pp.63-69
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• 2011

To propose the evaluation criteria of substantial sustainable low-carbon long-life housing, this study subdivided an existing planning item composed of the simple enumeration type by coding system of high/middle/low classification according to the core technology, and it was subdivided by a total 203 piece item. In other words, it subdivided 4 divisions by apartment unit, building, park and equipment, and classified elemental technology and system were divided by passive/active elemental technology and system according to the design process of long-life housing. Besides that, this paper presents the restructure results of checklist with quantitative criteria that classified by the weighting factor and compatibility between law system and current planning criteria in domestic long-life housing.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2005.11a
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• pp.133-136
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• 2005

While reconstruction has been criticized since 1990 for its tendency of resource over-usage and negative impact on the surrounding environments, remodeling has begun drawing attention as its new alternative. Through examining the recent legal and systematic conditions such as Construction Law, Common Housing Administration Ordinance, and Housing Law, etc. this research analyzes problems on the current legal systems on remodeling, and it aims to suggest systematic and policy-driven schemes which could revitalize remodeling on its software and hardware sides. Careful consideration in regards to remodeling should be given from the initial design stage and throughout the maintenance stages of construction to achieve lengthy durability of buildings, and realization of long-term maintenance costs should also be pursued during this process. This will set in place the practice of remodeling in longer than 50-years intervals since the construction rather than the current 20 or 30 years.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.35 no.3
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• pp.110-117
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• 2012

A product family design has received much attention over the last several decades, since a product family-based development shortens lead-times and reduces cost, as well as increases efficiency and effectiveness of the product realization process. It is challenging work, however, to define the product family design in the heterogeneous product development environments, due to myriads of products related information described in different ways across products in any companies. In this paper, we provided a way of defining product family design framework using formal concept analysis and ontology language. Based on this, the specific product family can be derived by ontological reasoning, and the new product concept can be also expanded in the framework. The proposed framework is formalized using OWL (Web Ontology Language) and implemented in $Prot{\acute{e}}g{\acute{e}}$. Actual product family design algorithm is carried out using FaCT++ engine, a plug-in to $Prot{\acute{e}}g{\acute{e}}$, and the benefits of the proposed method are also demonstrated through a case study.

• Journal of Power System Engineering
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• v.15 no.5
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• pp.54-60
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• 2011

In this study, an analytical realization of end-milling system was introduced using recursive parametric modeling analysis. Also, the numerical mode analysis of end-milling system with different conditions was performed systematically. In this regard, a recursive least square(RLS) modeling algorithm and the natural mode for real part and imaginary one was discussed. This recursive approach (RLSM) can be adopted for the on-line system identification and monitoring of an end-milling for this purpose. After experimental practice of the end-milling, the end-milling force was obtained and it was used for the calculation of FRF(Frequency response function) and mode analysis. Also the FRF was analysed for the prediction of a end-milling system using recursive algorithm.