• Journal of Applied Reliability
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• v.18 no.1
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• pp.80-86
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• 2018

Purpose: This article provides a mathematical model for the accelerated degradation test when the performance degradation characteristic follows the lognormal distribution. Method: For developing test plans, the total number of test units and the test time are determined based on the minimization of the asymptotic variance of the q-th quantile of the lifetime distribution at the use condition. Results: The mathematical model for the accelerated degradation test is provided. Conclusion: Accelerated degradation test method is widely used to evaluate the product lifetime within a resonable amount of cost and time. In this article. a mathematical model for the accelerated degradation test method is newly developed for this purposes.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.36 no.6
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• pp.381-389
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• 1987

This paper presents a method for optimal load shedding in preserving a system security following abnormal condition as well as a sudden major supply outage. The method takes account of static characteristic of generators control and voltage and system frequency characteristic of loads. The optimization problem is solved by a gradient technique to get the maximal effect by the least quantity of load shedding considering line overloads as well as voltage disturbances and system frequency. The method is illustrated on a 8-bus system. It has been found that the use of the proposed algorithm for model systems alleviate the line overload more efficiently than the former method. It is believed that this method will be useful in security studies and operational planning.

• Proceedings of the Safety Management and Science Conference
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• 2000.05a
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• pp.481-490
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• 2000

First, in order to improve selecting method of quality characteristic level desired by customers, S/H(Signal-to-Noise) ratio of Taguchi in larger-the-better characteristics was applied. Second, the Matrix classification standard of ACE(Attribute Categorization Evaluation) is presented using KANO model on difference analysis of importance and satisfaction through questionnaire from customers. This is for reflecting the diverse EC which customers want in EC quality sufficiently. Also, establishing sales point will be helpful in business strategy through presenting types that are able to decide planning quality. Third, the important measure of EC about correlation among quality characteristics and a new weight o( EC are calculated depending on importance of EC and the weight of customer attribute and materials of relationship matrix through correlation matrix analysis.

• Journal of Institute of Control, Robotics and Systems
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• v.17 no.2
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• pp.108-115
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• 2011

This paper describes a new sensor system for mobile robot motion estimation using stereo infrared light sources and a camera. Visibility is being applied to robotic obstacle avoidance path planning and localization. Using simple visibility computation, the environment is partitioned into many visibility sectors. Based on the recognized edges, the sector a robot belongs to is identified and this greatly reduces the search area for localization. Geometric modeling of the vision system enables the estimation of the characteristic pixel position with respect to the robot movement. Finite difference analysis is used for incremental movement and the error sources are investigated. With two characteristic points in the image such as vertices, the robot position and orientation are successfully estimated.

• Journal of The Korea Institute of Healthcare Architecture
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• v.10 no.2
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• pp.125-133
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• 2004

Safety, accessibility and distinguishment as the concept of architectural planning and design are demanded in staircases due to increase of the old aged people and disabled people's enlarged social participation. In this research is tried to provide the importance of vertical walking function at the design for the staircases. For this reason, structural elements of the staircases are studied in the ergonomic aspect for barrier-free environment and a comparative study is made on the regulations of the staircases in the inside and outside of the country in disabled & aged people's view. Based on this study, the quality of the staircases in public facilities and Apartments is analyzed. As the result, it has been proved that the vertical walking function of the staircases is the most fundamental characteristic of the staircases design before everything else.

• Journal of the Korean Institute of Rural Architecture
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• v.10 no.1
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• pp.75-82
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• 2008

This study is about land use and site plan for resident redevelopment for districts with existing residents. The study suggests development direction focusing on preserving the regional characteristics, and presentation of suburban-style housing complex reflecting on the future tenant's individuality and demand. The preexisting development approach for suburban-style housing complex which was planned by the developer, failed to recognize taste of the future tenants. Profitability being the priority, it also resulted in a serious environmental disruption. In this development however, through a systematic direction for site development and site analysis, conducting surveys through future tenants, attempted for a continuous growth of the community. The study is presented covering the following areas; site's pathway system, nature conservation plan, lot plan, land use and arrangement plan, and community facility.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.984-987
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• 2003

In order to rapidly catch up urban region’s detailed land-use or land-cover information; this research used the post-classification algorithm (Spatial Reclassification Kernel: SPARK) to create a land-use map of Taichung City. We discussed the urban land-use classification model with the IKONOS images. The conclusions may be distinguished as follows:(a) Using the Maximum-Likelihood algorithm to classify seven broad land-cover categories. The overall accuracy in this stage achieves 92.72% and Kappa coefficient will be obtained 0.91; and (b) Using the SPARK method to classify images for detect the land-use, the overall accuracy achieves higher 89.64% and Kappa coefficient will be 0.86. To conclude, the research process in this study can fully and carefully describe local land-use pattern and assist the demand of land management and resources planning reference.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.64 no.4
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• pp.634-639
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• 2015

In order to understand phenomenon of the electric railway power feeding system in the construction planning step, analysis of the overall system including electric characteristic of electric railway power feeding system, train running characteristic and power consumption pattern and train operation plan and gradients of railroad and curve radius is required. This paper study the feeder system by analysis of comprehensive system according to train operation plans, line impedance, running characteristic of train, electrical properties of the feeder system. In order to understand phenomenon to the feeder system of tram exactly regarding export of the field railroad preceeding actively recently.

• Journal of The Korea Institute of Healthcare Architecture
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• v.24 no.4
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• pp.59-67
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• 2018

Purpose: The concept of the Barrier-Free Design has steadily expanded into a basic principle of design, which can provide safe and convenient lives not only limited to the disables, elders, and pregnant women, but also to all members of the society. This is what we now know as the Universal Design. In other words, Barrier-Free Design for all is Architectural Approach of Universal Design. Thus, as a future-oriented alternative to school facilities according to social change, this study suggests basic direction of school building planning and concept of universal design considering school facilities characteristics. Methods: The characteristics of school facilities are understood from the perspective of Universal Design. In addition, a survey is conducted to identify the current state of school facilities. Result: Findings from this study are as follows. First, Universal Design of School Building is an integrated characteristic. Integration is intended to create and manage an integrated environment instead of an individual and one-time approach to installation and maintenance of convenience facilities. Second, It is a flexible characteristic to be sustainable. In other words, they aim to be selectable to respond to change. Third, It is a characteristic of accumulation of outstanding cases. This means that not only individual schools but also entire school spaces will be applied to Universal Design to form a virtuous circle of environment improvement. Implications: The results of this study may serve as a basic concept in the design of school buildings.

• Proceedings of the KSR Conference
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• 2004.10a
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• pp.1646-1651
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• 2004

This primary study describes some proposition of restoration and rehabilitation of rail station and station impact area for efficient use. Therefore, I reviewed the functions and roles about rail station and other railway facilities related with urban structures and development, and also analysed the case studies about realignment of rail station, and then, suggested primary management plan of efficient railway installation. This study has some bounds and limits owing to the descriptive reviews but not detailed analyses. Hereafter, I am planning to consider the management plan for efficient railway installation use as coinciding with specific city characteristic and comprehensive plan such as rearrangement of the station.