• Journal of the Korea Concrete Institute
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• v.13 no.5
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• pp.430-437
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• 2001

Recently, there have been increased much concerns about repair and rehabilitation works for aged concrete structures. It is in particular known that due to repeated overburden vehicles, there are significantly increasing number of aged concrete bridge slabs, which are strongly needed to construct and rehabilitate by innovative construction method. The objective of this research is to develop the new construction method of concrete slab in bridge superstructure, which can contribute to minimize a traffic congestion during repair and rehabilitation works of aged concrete slab, and can sufficiently assure the quality through the minimization of in-situ works at the site. I-beams with punch holes, which are substituted instead of main reinforcing steels in concrete slabs, can be manufactured in accordance with the specification in the factory, and be preassembled into the panel. After erecting the preassembled panels in the site, concrete will be poured into the slab panel. This research is to investigate mechanical properties of I-beam with punch holes itself, and then to investigate structural properties of assembled I-beam panels through static test, of which result can be utilized for the development of the new constructional method for concrete slab in bridge superstructure.

• Structural Engineering and Mechanics
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• v.45 no.4
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• pp.455-470
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• 2013

RC flat plates that have no flexural stiffness by boundary beams may be governed by a serviceability as well as a strength condition. A construction sequence and its impact on the distributions of construction loads among slabs tied by shores are decisive factors influencing immediate and long term performances of flat plate. Over-loading and tensile cracking in early-aged slabs significantly increase the deflection of a flat plate system under construction. A reshoring work may be helpful in reducing slab deflections by controlling the vertical distributions of construction loads in a multi-shored flat plate system. In this study, a change of construction loads by reshoring works and its effects on deflections of flat plate systems under construction are analyzed. The slab construction loads with various reshoring schemes are defined by a simplified method, and the practical calculation of slab deflections with considering construction sequences and concrete cracking effects is applied. From parametric studies, the reshoring works are verified to reduce construction loads and slab deflections.

• Proceedings of the Korea Concrete Institute Conference
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• 1995.10a
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• pp.219-223
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• 1995

Since the mid of 1970's, the construction of infrastructure has been booming and accelerating to keep up with rapid economic growth. Fast achievement of most construction activities has caused unfavorable effects of civil petitions associated with damages and nuisances due to last hasty works. it is well known that the falling down of Sungsoo bridge and the collapse of Sampoong department and other structures have occurred because of the construction not conforming with the specification, and thereby incurred enormous loss of life and property. Now a days. a periodic inspection and maintenance have been strongly interested on aged RC structures, of repair and reinforcement technique in the country, most repairing and reinforcing works have been performed on the basis of the guidance of few experienced local company in this field.

• Journal of Korean Academy of Nursing
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• v.25 no.2
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• pp.295-315
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• 1995

This qualitative nursing research used a hermeneutic phenomenological approach to discover meaning in mid - aged women's experience of mastectomy. The ultimate aim of the inquiry was to discover the essence of mid-aged women's experience and promote understanding. The study was guided by Van Manen's method for doing research. The method of inquiry included. turning to phenomenon of interest ; inquiring and investigating experience as it was lived rather than as conceptualized ; reflecting and analyzing essential themes which characterize phenomenon : and describing phenomenon through art of writing and rewriting. Multiple strategies for data collecting were needed : in depth face-to-face interview ; analysis of women's writings ; artistic works : and analysis of examples of phenomenon in art, litera lure, and drama. Although the experience was different for all of the women interviewd, essential themes of experience emerged : Self-discovering of vicious disease, Divining punishment-unfortunate women, loss of self though the scar, a night-mare, change of life values and attitudes, rediscovering living alone, living through with fearing of death. Findings from artistic and creative inquiry further validated findings and meaning descovered. The study illuminated meaning and simultaneously validated the phenomenological research process. Essential themes for understanding women's experience, implications for education, research, and practice, direction and need for continuing inquiry were identified.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.801-806
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• 2001

In the latest, the construction period became the most important factor in the domestic building works because buildings is higher and larger gradually. Accordingly, cold-weathering concrete constructions are performed more and more. So, the demands of concrete quality management methods are increased in cold-weathering concrete constructions. In this study, the mock-up experiment was performed to correct input data in the kimpo H construction field. Using the results of this experiment, the method of temperature analysis was presented to prevent early aged freezing damage and to control thermal crack in this study.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.4D
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• pp.345-356
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• 2012

Road pavement requires repetitive maintenance works to maintain satisfactory service level to the public. However, the repetitive maintenance works upon deteriorated pavement structure make negative effects to deterioration speed. It often leads to inefficient use of limited budget. For that reason, the pavements require reconstruction work to recover their original performance. Recently, construction demands in the Korean national highway have already been reached to maximum level, and the aged pavements start to demand much more reconstruction works. However, in the real world, road agencies have often been confused when they determine maintenance design for such aged road sections due to budget constraint. It is because there is no reliable long-term maintenance strategy that supports their decision making. To support their decision making, this paper aimed to suggest the best maintenance strategy considering changing process of pavement performance by repetitive maintenance works. As an analysis method, probability distribution and hazard function to estimate the life expectancy were adopted, and then the results were used for long-term life cycle cost analysis with deterministic or Monte-Carlo method under various scenarios. As an empirical study, the Korean national highway data that has long-maintenance history data since 1986 has been applied. Last, this paper considered quality assurance of maintenance work to improve maintenance quality. These could be important information as a part of long-term maintenance strategy of pavement.

• Journal of Electrical Engineering and Technology
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• v.10 no.1
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• pp.355-363
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• 2015

HVDC technology has become popular as an economic mode of bulk power transmission over very long distances. Polymeric insulators in HVDC power transmission lines are affected by surface tracking and erosion problems due to contamination deposit, which pose a greater challenge in maintaining the reliability of the HVDC system. In addition, polymeric insulators are also naturally affected by aging due to various environmental stresses, which in turn accelerates the surface tracking and erosion problems. Research works towards the improvement of tracking and erosion resistance of polymeric insulators by adding nano-sized fillers in the base material are being carried out worldwide. However, surface tracking and erosion performance of nano-filled aged polymeric insulators for HVDC applications are not well reported. Hence, in the present work, tracking and erosion resistance of the nano $Al(OH)_3$ filled silicone rubber insulation material has been evaluated under DC voltages at different filler concentrations and aged conditions, as per IEC 60587 test procedures. Leakage current and contact angle measurements were carried out to understand the surface hydrophobicity. Moving average technique was used to analyze the trend followed by leakage current. Water aged specimen shows less tracking resistance when compared with thermal aged specimen. It is observed that nano-filler concentration of 5% is even sufficient to get better tracking/erosion resistance under DC voltages.

• Journal of The Korean Digital Architecture Interior Association
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• v.11 no.1
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• pp.73-81
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• 2011

The purpose of this research is to analyze the emotional characteristics of community space with recently constructed apartment complexes. The designated subjects of this research are located in Dongtan the first New Town, with 500 to 1000 households and constructed as single buildings for community space are 14 apartment. The results are as follows: 1)The space for day care planned for children's emotional comfort and stability measured by symbolizing image of nature. Also, allowing children to recognize their own space by decorating the walls with the works of themselves and their friends was shown to break down extraneous feelings against other spaces, and allow intimacy for spaces. 2)The space for the aged was shown to give a secure and friendly feeling by considering the psychological and physical traits of the elderly. It can replenish the depressed bodies of aged people with vigor and stimulate their emotion. 3)The space for indoor exercise utilized various visual facilities, such as graphics and images, to bring out specific areas and create affiliation in stimulating the emotion of residents.

• Journal of Electrical Engineering and Technology
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• v.9 no.5
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• pp.1660-1669
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• 2014

Partial discharge (PD) detection plays a major role in the life time assessment of liquid insulation in power transformers. Many research works are being carried out to replace conventional mineral oil insulation in transformers by vegetable oils. It is necessary to understand the PD characteristics of vegetable oils before recommending them as an alternate for mineral oil. In this paper, the breakdown strength and PD characteristics of palm and corn oil were investigated in both unaged and thermally aged conditions. Laboratory experiments were performed as per IEC test procedures. PD signals were measured using wide band detection system. Phase resolved PD pattern of vegetable oils and mineral oil were compared. Effect of increase in voltage stress on the PD pattern of palm and corn oil were studied. Time and frequency domain analysis of PD pulses at needle-plane electrode configuration was carried out. Statistical analysis of PD pattern i.e. skewness and shape parameter variations with respect to applied thermal stress were also carried out. From the results, it is observed that palm and corn oils have better breakdown strength and PD characteristics even under long-term thermal stress and hence they can be used for power transformer applications.

• Fashion & Textile Research Journal
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• v.13 no.6
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• pp.848-855
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• 2011

The purpose of this study is to develop design for daily hanbok with Jacquard textile design developed by using the traditional patterns that suit the needs and lifestyles of the middle and old aged group. This study will also develop Jacquard textile design that has elaborate and luxurious patterns and abundant expression of colors using the traditional patterns that suit the needs and lifestyles of the middle and old aged group. Developing daily hanbok design for woman's casual and formal occasion will contribute to fashion business significantly by popularization of daily hanbok as one of the important fashion genre. The "Texpro Design CAD V8.21" program was used for the textile design. A total of 2 designs were developed as the Jacquard textile design with traditional patterns using flower motifs. One type of fabric was produced for each of the textile design with a color selected from "Pantone Color Chips". And finally, four woman's daily hanbok design for either casual or and formal style were developed and these daily hanboks were consisted of one set of jacket and trouser, durumagi, one set of jacket and skirt and one set of vest and trouser. And the actual garments were constructed and the design procedure and the photos of these works were presented. This study showed the possibility of producing highly sensible daily hanbok that suits the fashion trend of middle aged women and the widening of consumer range and the creation of new market by developing Jacquard textile design.