• Proceedings of the Korean Nuclear Society Conference
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• 1996.11a
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• pp.79-84
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• 1996

The robust controller for the nuclear reactor power control system is designed. The reactor model is set up by use of the point kinetics equations and the singly lumped energy balance equations. Since the model is different from the actual plant, the controller which makes the system robust is necessary. The perturbation of the actual plant is investigated with respect to several possible sources of uncertainty. Then the overall system is configured into the two port model and the $H_{\infty}$ controller is designed. The loop shaping and the permissible control rod speed are considered as the design constraints. The designed $H_{\infty}$ controller provides the sufficient margins for the robustness, and the system output as well as the control input satisfy their relevant requirements.

• Proceedings of the KSRS Conference
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• 1999.11a
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• pp.405-410
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• 1999

Topographic maps can be made and updated with satellite images, but it requires many human interactions that are inefficient and costly. Therefore, the automatizing of the road extraction procedures could increase efficiency in terms of time and cost. Although methods of extracting roads, railroads and rivers from satellite images have been developed in many studies, studies on the road extraction from satellite images of urbanized area are still not relevant, because many artificial components In the city makes the delineation of the roads difficult. So, to extract roads from high resolution satellite images of urbanized area, this study has proposed the combined use of wavelet transform and multi-resolution analysis. In consequence, this study verifies that it is possible to automatize the road extraction from satellite images of urbanized area. And to realize the automatization more completely, various algorithms need to be developed.

• Journal of Technologic Dentistry
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• v.33 no.2
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• pp.137-145
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• 2011

Purpose: To evaluate the accuracy of zirconia copings in terms of clinical verified for the clinical application of CAD/CAM. Methods: Zirconia copings (n=5) were prepared using CAD/CAM system and were sintered using the relevant electrical induction furnace, which uses a 2h sintering program with a maximum temperature of $1500^{\circ}C$. The copings placed at the models and the interval values were measured. Results: The meas interval values between the die and the zirconia copings were $44.14{\mu}m$(A), $44.57{\mu}m$(B), $44.72{\mu}m$(C). 51.05 ${\mu}m$(D). Conclusion: The maximum interval values between the die and the zirconia copings were $51.3{\mu}m$ which is acceptable for clinical use. ${\mu}m$ Proper understanding of the test conditions will help enhancing the accuracy of zirconia coping.

• The Journal of Society for e-Business Studies
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• v.8 no.1
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• pp.103-111
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• 2003

Nowadays XML is used for exchanging information in e-Commerce, especially B2B. Necessity of XML DBMS has being increased to efficiently process XML data. So a lots of database products for supporting XML are rapidly appeared in the market. In this paper, we made an XML DBMS system based on Generic Data Model. First we developed XML Adaptor based on Generic Data Model and added it on relational DBMS for developing XML DBMS. XML Adaptor is composed of Query Convertor and XML Repository System. The Query Convertor parse commands that are for XML data manipulation and then call the relevant component of XML Repository System for relational database operation. The XML Repository System handles relational database operations such as create, delete, store, and etc. In this way we can use a relational DBMS for manipulation XML data. Therefor we can build more economically XML DBMS.

• Journal of the Korean Society of Safety
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• v.28 no.5
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• pp.83-89
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• 2013

Occupational Safety and Health Act provides that industrial safety helmets are personal protective equipment(PPE) to protect heads against falls from a height. Relevant domestic regulations are distinguished and different from other countries' cases. This study investigated industrial safety helmet's protective purposes and characteristics related to falls and the notion of fall prevention. A comparative analysis of regulations on safety helmets and fall prevention as well as standards on safety helmet's impact test requirements is followed by a literature review. It is also suggested that the term "fall" related to safety helmets should be changed to "impact on the upper part of head" in domestic regulations and standards.

• Communications for Statistical Applications and Methods
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• v.22 no.1
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• pp.41-54
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• 2015

In this article, we propose nonconcave penalties on a reduced-rank regression model to select variables and estimate coefficients simultaneously. We apply HARD (hard thresholding) and SCAD (smoothly clipped absolute deviation) symmetric penalty functions with singularities at the origin, and bounded by a constant to reduce bias. In our simulation study and real data analysis, the new method is compared with an existing variable selection method using $L_1$ penalty that exhibits competitive performance in prediction and variable selection. Instead of using only one type of penalty function, we use two or three penalty functions simultaneously and take advantages of various types of penalty functions together to select relevant predictors and estimation to improve the overall performance of model fitting.

• BMB Reports
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• v.37 no.1
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• pp.59-74
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• 2004

The study of whole patterns of changes in protein expression and their modifications, or proteomics, presents both technological advances as well as formidable challenges to biological researchers. Nutrition research and the food sciences in general will be strongly influenced by the new knowledge generated by the proteomics approach. This review examines the different aspects of proteomics technologies, while emphasizing the value of consideration of "traditional" aspects of protein separation. These include the choice of the cell, the subcellular fraction, and the isolation and purification of the relevant protein fraction (if known) by protein chromatographic procedures. Qualitative and quantitative analyses of proteins and their peptides formed by proteolytic hydrolysis have been substantially enhanced by the development of mass spectrometry technologies in combination with nanoscale fluidics analysis. These are described, as are the pros and cons of each method in current use.

• Journal of Technology Innovation
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• v.23 no.3
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• pp.317-340
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• 2015

Firms and individuals who have invented new technologies have options to keep them secret, to apply for patents or to defensively publish them. Defensive publication is strategic use of patents by withdrawing patent applications to make the relevant information public. This paper empirically analyzes the determinants of patent withdrawals and finds that withdrawal of patents before examination of patent office squares with the implication from the defensive publication theory. The paper also shows the importance of applicant type which has been overlooked in previous studies of the patent withdrawal.

• Environmental Analysis Health and Toxicology
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• v.24 no.3
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• pp.261-270
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• 2009

To make measurable regulatory decisions of chemicals, it is necessary to consider their effect on the human health and ecosystem. In principle, this is based on relevant toxicity studies conducted by accepted guidelines. However, current regulatory programs in various countries confront challenges related to risk assessment of large numbers of chemicals within the restricted resources and time. Therefore there is a need for more efficient approach to limit the number of tests to be conducted. This promotes the development of powerful nontesting methods (e.g. (Q)SARs) and permits to use the predicted data for regulatory purpose. In this article, current status of non-testing methods in various chemical regulatory programs was reviewed in terms of their application and research activity on them. Finally, their usefulness associated with development of domestic regulatory program was suggested.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.27 no.7
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• pp.101-107
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• 2013

IEC Standards on lightning protection system specify the use of natural components as down conductors. This paper provides an analysis of problems revealed from our field investigation and survey conducted for the relevant experts in the construction site where natural components are used as down conductors. It also considers a suitable condition for installing natural components as down conductors in accordance with the latest version of the standard. As a result, when rebars of reinforced concrete are used as down conductors, vertical bars consisting of rebars of which thickness is not less than D13($127mm^2$) should be connected by welding, clamps or bound joints, using appropriate connection components conforming to IEC Standards. The lashed joints, however, shall not be applied for down conductors.