• Transactions of the Korean Society of Automotive Engineers
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• v.23 no.4
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• pp.410-419
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• 2015

In this study, the roadability, fuel economy and emission characteristics were evaluated for a natural gas converted vehicle. The results are as follows; Not only the shortage of power was observed in stall test, but also large deterioration of acceleration performance was exposed in roadability. Compared to the original LPG system, the acceleration is 76% in start acceleration and 45 ~ 65% in overtaking acceleration, especially the decline became larger when air conditioner is at work. Furthermore, because the mapping data, which controls the injection depending on driving condition, do not match up with injection system, the failure of air-fuel ratio feedback control occurs resulting from the large gap between the required and the really supplied amount of fuel. This failure cause the exhaust gas to emit without catalytic conversion and the fuel economy based on the fuel heat value to get worse 22% in the mode test and 16% in road test respectively. In addition, the existing injection system does not secure enough fuel at the starting so that it may lead to the fail of clod start, the deterioration of hot start and inharmonic of engine at the idle after start.

• Transactions of the Korean Society of Automotive Engineers
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• v.24 no.4
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• pp.463-470
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• 2016

In this paper, the characteristics analysis of LMD track, such as including track structure, track wear resistance and track thickness, were analyzed to enhance the deposition efficiency using a diode-pumped disk laser. SKD61 hot work steel plate and Fe based AISI M2 alloy were used as a the substrate and powder for the LMD process, respectively. The laser power, track pitch and powder feed rate among LMD parameters were adopted to estimate the deposition efficiency. As the laser power is increased, heat input and melting pool on the substrate is grown also increases, so resulting in the increased LMD track thickness was increased. Through EPMA mapping analysis of the cross-section in the LMD track, it was observed that all the elements are evenly distributed inside. Therefore, the entire hardness in the LMD track is expected to be almost uniform regardless of location. The characteristics of the LMD specimen were excellent compared to the STD11 specimen in terms of the wear track width and the wear rate as well as the coefficient of friction. Especially the wear rate of LMD specimen has been significantly reduced by 60 % or more. From Based on the experimental results, the prediction formula of LMD thickness was calculated by using laser power, track pitch and powder feed rate.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.05a
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• pp.87-88
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• 2016

In order to assess the design value of engineering work from the point of view of LCC (Life Cycle Cost) in Korea, it is mandatory for all construction works that the total construction costs are over 10 billion won. The LCC includes initial construction costs, maintenance & operation costs, energy costs, end-of-life costs, and so on. Among these, the portion for maintenance & operation costs for a building is sizeable, as compared to the initial construction costs. Furthermore, the paradigm for construction industry has rapidly shifted from 2D to BIM, which includes design planning and data management. However, the study of BIM-based LCC analysis is not adequate today, even though all domestic construction projects ordered by the Public Procurement Service have to adopt BIM. Therefore, this study suggests a methodology of BIM-based LCC analysis that is particularly focused on repair and replacement (R&R) cost. For this purpose, we defined requirements of calculating R&R cost and extracted X from the relevant IFC data. Thereafter, we input them to the ontology of calculating the initial construction costs to obtain an objective output. Finally, in order to automatically calculate R&R cost, mapping with R&R criteria was performed. We expect that our methodology will contribute to more efficiently calculate R&R cost and, furthermore, that this methodology will be applicable to all range of total LCC. Thus, the proposed process of automatic BIM-based LCC analysis will contribute to making LCC analysis more fast and accurate than it is at present.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.25 no.4
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• pp.235-263
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• 2014

Library of Congress introduced BIBFRAME as a new bibliographic framework to enhance web accessibility of bibliographic records and their integration to Web of data. This study introduces BIBFRAME model and its current status, reviews BIBFRAME classes and properties, and presents a mapping between MARC21 and BIBFRAME. The study aims to help the understanding the deployment of BIBFRAME in bibliographic description. BIBFRAME categorizes bibliographic entities into Work-Instance, and employs RDF/XML and URIs to identify resources and specify semantics of the resources on the Web. It also suggests an Annotation entity to provide additional information produced by users and external organizations. BIBFRAME is significant in that it presents a new paradigm of bibliographic description and expands users' information discovery in the context of Linked Data. Continuous researches are required to support its content model agnostic application to diverse resource type, which may entail a modification of BIBFRAME model and vocabulary. It also calls for guidelines for using the complicated vocabulary in a coherent way.

• Journal of Korean Academy of Nursing Administration
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• v.11 no.3
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• pp.289-301
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• 2005

Purpose: This study was to examine the ego-identity of nursing students and their adjustment to home and university in an effort to identify the correlation of their ego-identity to their adjustability and lay the foundation for providing better personality education to them. Method: The subjects in this study were 400 nursing students at H and S universities in south Chungcheong province. The instruments used in this study were Park A-cheong(2003)'s Korean-version Ego-Identity Inventory and Jeong Jonggweon(1998)'s Home and School Adjustment Inventory. For data analysis, SPSS/PC+ Package was used, and statistical data on frequency and percentage were obtained. Besides, t-test, one-way ANOVA and Pearson correlation coefficient were employed. Result: The findings of the study were as follows: The nursing students investigated got a 3.46 and 3.53 in ego-identity and family life adjustment respectively out of possible five points, which were both above the average. Their score in school adjustment was 2.89, which wasn't high. As for connections between general characteristics and ego-identity, their academic school year, their type of residence, presence or absence of parents and their birth order made no statistically significant differences to their ego-identity. But as to motivation of choosing nursing, the students who chose their major at their own option were the best in that regard. Their adjustment to family life made no significant differences, and regarding school adjustment, ego-identity was better among those who lived in a lodging house or dormitory(F=4.01, p<.05) and who chose their major at their own option(F=4.88, p<.01). In addition, those with better ego-identity were better adjusted to home and school. Conclusion: As the above-mentioned findings suggested that nursing educators should teach students by mapping out specific plans to enhance the ego-identity of students and facilitate their school adjustment, and full-fledged nurses should be produced by teaching students to build the right work ethics and become qualified as a professional.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.12
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• pp.2636-2641
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• 2010

To support anti-collision between ship to ship and sea-search and sea-rescue work, ship automatic identification system(AIS) that can both send and receive messages between ship and VTS Traffic control have been adopted. And port control system can control traffic vessel service which is co-operated with AIS. For more efficient traffic vessel service, ship recognition and display system is required to cooperated with AIS. In this paper, we propose ship detection system which is co-operated with AIS by using background estimation based on image processing for on the sea or harbor image extracted from camera. We experiment with on the sea or harbor image extracted from real-time input image from camera. By computer simulation and real world test, the proposed system show more effective to ship monitoring.

• Journal of Electrical Engineering and Technology
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• v.13 no.2
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• pp.902-910
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• 2018

In recent times, development of nanofluid insulation for power transformers is a hot research topic. Many researchers reported the enhancement in dielectric characteristics of nano modified mineral oils. Considering the drawbacks of petroleum based mineral oil, it is necessary to understand the dielectric characteristics of nanofluids developed with natural ester based oils. Palm oil has better insulation characteristics comparable to mineral oil. However very few research reports is available in the area of nanofluids based on palm oil. Partial discharge (PD) is one of the major sources of insulation performance degradation of transformer oil. It is essential to understand the partial discharge(PD) characteristics by collecting huge data base of PD performance of nano modified palm oil which will increase its confidence level for power transformer application. Knowing these facts, in the present work, certain laboratory experiments have been performed on PD characteristics of nano $SiO_2$ modified palm oil at different electrode configurations. Influence of concentration of nano filler material on the PD characteristics is also studied. Partial discharge inception voltage, Phase resolved partial discharge (PRPD) pattern, PD signal time-frequency domain characteristics, PD signal equivalent timelength-bandwidth mapping, Weibull distribution statistical parameters of PRPD pattern, skewness, repetition rate and phase angle variations are evaluated at different test conditions. From the results of the experiments conducted, we came to understand that PD performance of palm oil is considerably enhanced with the addition of $nano-SiO_2$ filler at 0.01%wt and 0.05%wt concentration. Significant reduction in PD inception voltage, repetition rate, Weibull shape parameter and PD magnitude are noticed with addition of $SiO_2$ nanofillers in palm oil. These results will be useful for recommending nano modified palm oil for power transformer applications.

• Journal of the HCI Society of Korea
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• v.10 no.2
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• pp.65-71
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• 2015

In this paper, we present binocular augmented reality system with smartphones. With improvements of performance and resolution of recent smartphones, various virtual reality devices using smartphones and applications are appearing in the market. But the augmented reality system with smartphones are not that popular because of the lack of required technologies. In our work, we discuss about 3D mapping and tracking using computer vision. Also, we provide hybrid tracking using sensors in the smartphone which can handle the computer vision failure cases. Bare hand 3D interaction method in our system will be also presented.

• Journal of KIISE:Computer Systems and Theory
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• v.32 no.4
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• pp.168-176
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• 2005

We propose a method for 3-dimensionally reconstructing an object using a line that includes the midpoint information from a single image. A pre-defined polygon is used as the primitive and the recovery is processed from a single image. The 3D reconstruction is processed by mapping the correspondence point of the primitive model onto the photo. In the recent work, the reconstructions of camera parameters or error minimizing methods through iterations were used for model-based 3D reconstruction. However, we proposed a method for the 3D reconstruction of primitive that consists of the segments and the center points of the segments for the reconstruction process. This method enables the reconstruction of the primitive model to be processed using only the focal length of various camera parameters during the segment reconstruction process.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.1377-1379
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• 2003

Satellite and aerial remote sensing (RS) techniques have been provided to collect spatial data globally over the last few decades. However in developing countries such as China, there is still an urgent need for low cost and high resolution RS data. As an emerging RS platform, commercial Unmanned Aerial Vehicle (UAV) integrated with state-of-the-art sensors and information technologies has the potential to become a low cost tool to meet application demands. In this paper, the architecture of UAV RS operation system is mentioned. Moreover, key technologies in UAV RS system are analyzed and current work is reported.