• Journal of Korean Society of Water and Wastewater
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• v.32 no.5
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• pp.435-443
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• 2018

Most of aged water supply pipes have been replaced by the open cut method. However, this method has some limitations because water pipes, in many cases, are buried together with other underground facilities or are buried in the middle of high-traffic roads or in narrow alleyways where boring machines cannot be used. This research developed a pipe bursting device for small diameter pipes that enables pipe replacement without excavating the ground, by the busting of existing buried pipes followed by the traction and insertion of new pipes. As a results of examining the field applicability of the developed device, PE pipes and PVC pipes required the tractive force of 413.65~665.69 kgf and 457.43~791.35 kgf respectively, plus an additional 30 % tractive force per elbow. The proper number of bursting head was demonstrated that the connection of more than 2 heads could secure a stable bending radius of 15D. The developed device can be improved through field experiments involving various pipe types and pipe diameters, as well as presence/absence of elbow, so as to be utilized regardless of diverse variables according to the conditions of the soils surrounding existing pipes.

• Journal of Ocean Engineering and Technology
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• v.29 no.5
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• pp.366-372
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• 2015

Ocean energy is one of the most promising renewable energy resources. In particular, South Korea is one of the countries where it is economically and technically feasible to develop tidal current power plants to use tidal current energy. In this study, based on the design code for HARP_Opt (Horizontal axis rotor performance optimizer) developed by NREL (National Renewable Energy Laboratory) in the United States, and applying the BEMT (Blade element momentum theory) and GA (Genetic algorithm), the optimal shape design and performance evaluation of the horizontal axis rotor for a 200-kW-class tidal current turbine were performed using different numbers of blades (two or three) and a pitch control method (variable pitch or fixed pitch). As a result, the VSFP (Variable Speed Fixed Pitch) turbine with three blades showed the best performance. However, the performances of four different cases did not show significant differences. Hence, it is necessary when selecting the final design to consider the structural integrity related to the fatigue, along with the economic feasibility of manufacturing the blades.

• Journal of Family Resource Management and Policy Review
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• v.21 no.1
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• pp.45-63
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• 2017

The purpose of this study was to emphasize the household financial education as a part of family life education, especially when provided at local community level; it also examines diverse measures by which to deliver such education. To this end, the current study focuses on the education programs of a healthy family support center, which has been established as a representative transmission system. The current status of its operations was examined, and practical measures by which to stimulate the delivery of financial education within that center were derived. In more detail, previous studies inside and outside of Korea were examined, and the current status of financial education included in the area of family life education was assessed; as a result of these assessments, the definition and objectives of financial education as family life education were adjusted. The limits of financial education that has been delivered thus far were reviewed, with the aim of proposing measures by which to sufficiently stimulate the delivery of financial education programs-programs that ultimately reflect the healthy family philosophy. This study proposes four specific measures by which to stimulate financial education. The first is the application of 'life cycle perspectives' to educational terms. The second is the activation of financial education programs that involve the family unit as educational subjects. Third, the delivery of lectures which related to the financing and nurturing of program coordinators was proposed. The fourth is drawing a connection between online and offline education in terms of effectively applying teaching methods. Ultimately, the results of this study can be used as basic data to inform the planning, development, and operational stages of financial education programs within family life education, which can be performed in healthy family support centers in the future.

• Journal of Information Management
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• v.41 no.1
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• pp.43-67
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• 2010

We examine several citation information services to analyze their functional items and resources as interests and concerns on citation information services have been increasing. Based on our analysis, we suggest a blueprint and model for national citation information services. As a result, We find that there are different service items and resources among the type of the citation information services. We also suggest three principles and personal services scenarios for developing national scholarly information service using citation information. And expert survey shows the priority of the services. This study would be a fundamental material for drawing big pictures on national citation information services.

• Journal of the Korean Society for information Management
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• v.14 no.2
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• pp.105-122
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• 1997

A library for the civil engineering field goes on increasing in quantity because of the growth in construction technology and the enlargement in applicable fields of civil engineering. Most of libraries and information centers in construction companies are using Dewey Decimal Classification (DDC) or Korean Decimal Classification (KDC) to classify a library in civil engineering field. It is necessary for the library classification system to be equipped with a more standardized code system, which corresponds to the academical and technical classification for the civil engineering works. This study analyzes the defects of existing classification systems, and then suggests a new classes and divisions classification system, which facilitates to link academic information with technical data, for the civil engineering field. The proposed system is expected to make practical application of information classification system in the construc ion industry and to be applied for the revised edition of KDC.

• Journal of the Korean Society for information Management
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• v.31 no.4
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• pp.7-28
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• 2014

This study analyses the questions addressed to the collaborative digital reference service run by the National Library of Korea. The data consist of 661 question entries to the 'Ask a Librarian' service during first 6 months in 2014. Each entry includes average 1.17 questions, and 77.82% of the total questions are real reference in nature. Questions are analyzed by classification division, context of the questioner, desired end product, activities of librarians, and the resources used to respond them. Each category is subdivided and analyzed in detail. Results revealed interesting findings and problems, and suggestions for further endeavor are provided.

• Journal of the Korean Vacuum Society
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• v.6 no.1
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• pp.1-8
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• 1997

The contamination structure and process on SUS 316 under various exposure conditions were investigated using x-ray photoelectron spectroscopy. The metal-oxide, metal-H-oxides, CO, COH, and $C_xH_y$ are the main components of contaminants on the SUS surface. The compositional profiles of the contaminants are shown to be $C_xH_y$/CO(COH)/metal-oxide on SUS. The contamination proceeds in two steps. The oxidation of the metallic constituents followed by adsorption of hydrocarbons. Under UHV conditions the contamination is mainly due to the oxidation, and, as the exposure time increases, the oxidation continues. In HV or higher pressure, most of the oxides are formed almost immediately after exposure and as the exposure time increases the contamination of hydrocarbons continues to grow. For the SUS sample exposed to atmosphere, the metal oxide is distributed deep inside the surface with an exponentially decreasing concentration, and its thickness is nearly in the order of photoelectron mean free path. It is also seen that the Fe oxide is segregated over Cr oxide in the highly oxidized samples.

• Journal of the Korean Society for Library and Information Science
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• v.33 no.1
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• pp.87-111
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• 1999

This article investigates the functions, needs, and developments of the MARC format for classification data. and recommends the development for the KORMARC format for classification data. It ae analyzes the record structure, content designation and the content of it mainly based on USMARC format. Structure and content designation are almost same with those of the bibliographic and authority formats. The data fields divided into functional blocks based on their functions. Record contents of the data in the fixed-length fields include more elements on the classification numbers, including type of number, classification validity, standard or optional number, synthesized number. Variable fields can be grouped into several blocks, inducing those for numbers and codes: for classification numbers and terms; for references and tracings; for notes fields: for index terms fields, and for number building fields. Data in each fields of this format have the same contents with those in other related fields as soon as possible. This article analyzes the content in each data fields in detail.

• Journal of the Korean Society for Library and Information Science
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• v.48 no.1
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• pp.415-439
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• 2014

The purpose of this study is to analyze mobile web accessibility of public libraries. To achieve this, accessibility checklists were driven from mobile web and application guidelines. The study also conducted automatic and manual evaluations. As results, the study found that text alternatives for resource image, main menu, image for text contents were mainly missing. In addition, focus for retrieval, operating system accessibility for retrieval, and id & password label, color difference for library calendar and seat reservation, brightness difference for main manu and resource display, and space between controls for retrieval were mainly missing. The study also suggested focal missing areas for main library services. It will be utilized as checklists for development of mobile services.

• Journal of the Korean Society for Library and Information Science
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• v.48 no.1
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• pp.75-95
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• 2014

The purpose of this study was to propose the improvements for high quality of National Library of Korea (NLK) Subject Headings List which was developed as a subject access tool in 2002. For this study, literature review, case study for subject headings lists of national libraries, and data analysis of headings and relationships were performed. Several problems were found as follows: inconsistency of subject headings descriptions, unclear and unnecessary relationships among headings, inconsistency of hierarchical relationships, lack of currency, incorrectness of classification numbers, duplication of newly requested terms, and assignment of non-preferred and unregistered terms in bibliographic records. Focusing on these problems, modifications of subject headings and bibliographic records, installation and operation of an review committee on subject headings, and supplementation of a manual were suggested to improve NLK Subject Headings List.