• Journal of the Korea Concrete Institute
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• v.18 no.4 s.94
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• pp.543-552
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• 2006

The current design for crack width control in concrete bridges is incomplete in analytical models. As one of the important serviceability limit states, the crack width be considered with the quantitative prediction of the initiation and propagation of corrosion and corrosion-induced cracking. A serviceability limit state of cracking can be affected by the combined effects of bond, slip, cracking, and corrosion of the reinforcing elements. Considering life span of concrete bridges, an improved prediction of crack width affected by time-dependent general corrosion has been proposed for the crack control design. The developed corrosion models and crack width prediction equation can be used for the design and the maintenance of prestressed and non-prestressed reinforcements by varying time, w/c, cover depth, and geometries of the sections. It can also be used as the rational criteria for the maintenance of existing concrete bridges and the prediction of remaining life of concrete structures.

• Journal of the Korea Concrete Institute
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• v.18 no.4 s.94
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• pp.469-477
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• 2006

Models to predict the ultimate strength of simply supported or continuous deep beams with web openings are proposed. The derived equations are based on upper-bound theorem. The concrete is assumed as a perfectly plastic material obeying the modified Coulomb failure criteria with zero tension cutoff. Reinforcing bar is considered as elastic-perfectly plastic material and its stress is calculated from the limiting principal compressive strain of concrete. The governing failure mechanisms based on test results are idealized as rigid moving blocks separated by a hyperbolic yield line. The effective compressive strength of concrete is calculated from the formula proposed by Vecchio and Collins. Comparisons with existing test results are performed, and they show good agreement.

• Journal of the Korea Concrete Institute
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• v.15 no.2
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• pp.297-304
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• 2003

This paper presents the test results of RCS(Reinforced Concrete Steel) beam-column joint with various types of transverse reinforcements such as small-column-type transverse reinforcements, four-piece ㄱ-shape assembled hoops and four-piece ㄱ-shape welded hoops. Five interior beam-column joint specimens were tested to examine the seismic performance and the shear strengths. From the test results, it was found that all the specimens sustained their strength at large levels of story drift(${\theta}$=0.035) without significant loss of strength and stiffness. Therefore it was concluded that the seismic performance and shear strength of the proposed RCS joint are at least the same as those of the specimen with conventional reinforcing details. Also, the contribution of the outer panel to the shear strength of the joint should be evaluated by the compression strut mechanism rather than compression field mechanism.

• Journal of the Korean Geosynthetics Society
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• v.19 no.3
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• pp.23-33
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• 2020

The lateral bearing characteristics are important factors in the case of large diameter drilled shafts and the measures to increase this are to improve the adjacent ground of the pile to increase the rigidity and to increase the rigidity of the pile itself. There are many suggestions for increasing rigidity by reinforcing casing on the pile, but few studies have been done related to this. Therefore, in this study, the lateral bearing characteristics according to casing reinforcement length were studied for each ground condition using non-linear analysis to evaluate the appropriate casing reinforcement length of the large diameter drilled shafts depending on the ground conditions. As a result, the lateral bearing characteristics of the large diameter drilled shafts are most effective if the casing reinforcement length ratio is 1.2, and depending on the ground conditions, the more loose the ground, the greater the reinforcement effect.

• Journal of the Korean Society of Hazard Mitigation
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• v.7 no.2 s.25
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• pp.7-12
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• 2007

This study has been conducted to present reform recommendations for Standardization of Construction Materials, based on a study on the Investigation of Demander's Consciousness for Construction Materials Quality and Information Standardization in Korea. Upon investigation, it was found that the quality of Korea Industrial Standards (KS) was given 67 points (out of 100) by respondents. In addition, 38% of the respondents showed that they had problems with a lack of Standardized Information. Good examples were found to be non-standardized materials, e.g. admixtures, waterproof agents, reinforcing fibers, concrete, aggregates, adhesives, wood, temporary materials, thermal-insulating materials, etc. Upon results from the investigation of demander's consciousness for infrastructure of standardization of information, 71.2% of respondents thought that it is necessary to informatize construction materials. They made following demands on the informatization to be, in order: Quality, Standard, Price (Cost), Operation, Drawing, Law, and Information.

• Journal of the Korean Society of Clothing and Textiles
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• v.34 no.5
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• pp.740-753
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• 2010

This study analyzes the motives of Korean women for choosing breast augmentation in a cultural and relational context; in addition, it investigates their evaluations after surgery. Data was collected through in-depth interviews with 10 Korean women in their 20s and 30s who have received cosmetic breast augmentation. Enlarged and made-up breasts are a form of clothing that symbolizes the socio-economic status of women. In the vertical and individualized Korean society, the desire of women for a fashionable body invigorated the appearance management market. Fashion consumers have passively internalized the ideal body trends as the concept of the ideal body-image, which has been constructed by the social structure, markets, and the media. The analysis was rooted in post-modern feminist perspectives on the female body. The ideal body-image internalization process through the social interactions of participants was the main cultural factor to choose breast surgery. The self-image and conformity/individuality of participant were categorized as relational factors for the motivation to undergo breast surgery. The result showed that after surgery the participants achieved positive feedback from their social relationships. They expressed or hid their socio-economic statuses through their purchased fashion bodies. They also showed higher self-esteem and feelings of satisfaction by pursuing individuality and conformity as a member of society. Moreover, they achieved wider fashion options and greater controls over their public/private/secret clothing choices for certain occasions. Cosmetic breast surgery positively empowered individual women while reinforcing the socially manipulated body ideals that oppress women at the same time. Participants internalized socially constructed values and justified their surgery choices.

• Journal of Korean society of Dental Hygiene
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• v.8 no.3
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• pp.73-84
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• 2008

This study conducted an interview questionnaire survey of 245 old people in some halls for the aged in the Daejeon Metropolitan City from June 1 to 31, 2008. on their attitudes toward and practice items for oral health, resulting in the following findings. 1. In terms of socio-demographic characteristics of the subjects, males females were 48.2% and 51.8% respectively, and in the educational level, no-education, elementary school graduation, middle school graduation, and high school graduation and higher were 27.8%, 33.9%, 26.5%, and 11.8%, respectively, showing the statistically significant difference (p=0.009). 2. In terms of attitudes toward oral health management by oral health care education, regarding questions of use of oral and dental hygiene products (p=0.016), experience in scaling, and whether or not they wear false teeth (p=0.018), a group having received the education rather than a group not having received it showed more positive oral health management attitudes, indicating the statistically significant difference. 3. In daily living inconvenience of acute oral health diseases according to oral health care education, acute oral diseases presents in a group with the education ($2.30{\pm}0.72$) lower than in a group without the education ($2.49{\pm}0.63$), indicating the statistically significant difference(p=0.031). 4. Factors of oral health diseases showed the significant relation with types of health insurance, subjective systemic health status, acute diseases and subjective oral health status (p<0.01), and the explanatory power or the final model was 38%. Accordingly it is thought that there is the indicated need for analyzing and grasping factors related to oral health diseases among the elderly through considering their attitudes toward and practice for oral health, and developing programs of enhancing the oral health of the elderly in order for them to change their attitudes and habits, and also reinforcing oral health care education for the elderly focused on making them perform oral health behaviors in a right way.

• Journal of Conservation Science
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• v.36 no.4
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• pp.284-295
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• 2020

This study focuses on reinforcement agents for wall damage, such as cracks, breakage, or delamination, for mural paintings from the Payathonzu temple. Experiments were conducted with filling and grouting agents based on the reinforcing method. In the filling reinforcement experiment, different mixing ratios of lime to sand, and additives (jaggery, seaweed glue, and Primal SF-016) were used. In the grouting reinforcement experiment, the mixing ratio of lime and pozzolan was the same, and the additive types were identical to the filling reinforcement experiment. The filling reinforcement experiment showed that there were fewer physical changes such as contraction, with a greater mixing ratio of lime to sand, however, the compressive strength decreased as the mixing ratio increased. With additives, the change in volume of agent decreased and the compressive strength increased, which was especially prominent for jaggery and Primal SF-016. The grouting reinforcement experiment showed that there was a remarkable contraction with an increased amount of moisture that originates from the characteristic of grouting agents that requires flowability. With additives, the water content of the agent decreased, whereas the compressive strength and adhesion increased. Among the additives, Primal SF-016 exhibited the highest compressive strength, and seaweed glue exhibited the most considerable viscosity and adhesion. The study results showed that the characteristics of reinforcement agents vary according to the mixing ratio and additives of the filling and grouting agents. Therefore, it is necessary to selectively apply the mixing ratio and additives for different reinforcement agents considering the wall damage for conservation treatments.

• Explosives and Blasting
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• v.20 no.4
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• pp.17-28
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• 2002

Safety concern is one of the most important parameters in the design of building demolition by explosive blasting, Accidents were sometimes reported due to the flying chips of fragmented materials In building demolition work in urban area. Laboratory experiments were performed to investigate the failure behavior of reinforced concrete pillars under blast loading and to develop an effective protection technique. Sixteen reinforced concrete pillars were constructed. The failure behavior and the flying chip velocities were observed by means of a high-speed camera. Protection scheme was designed and the effects of several protection materials were investigated. Two kinds of non-woven fabrics and wire net were tested as protection materials. The results showed that reinforcing bar was one of the important factors to determine specific charges, and that mesh size of wire net and tied-up method affected the protection of flying chips. Control of gas effects is also a key to the control of flying chips. It was recommended to use both wire net and non-woven fabrics as primary and secondary protection materials. Such protection scheme was successfully applied to the explosive demolition of apartment buildings.

• The Journal of Internal Korean Medicine
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• v.23 no.1
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• pp.117-122
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• 2002

Objective : We conducted this study to analyze some of the trends of treatments from the recent Chinese medical journals and contribute them to the oriental medical experiments and clinical research for the future. Methods : By referring to the Chinese medical journals that were published in China from 1999 to March, 2002, we analyzed the effective rates on frequency, methods, medical treatment, and diseases. Result : The average effective rate was 90.93%, which was very high. Lately, there have been no big changes in the methods of treatment. The methods of coordinating stomach-Qi, supplying Yin element, replenishing bone marrow, tonifying essence of life, and removing blood stasis are used by means of reinforcing Qi, producing blood, tonilying spleen, and replenishing the kidney. Conclusions : The decreased in bone marrow and leucopenia, and the side effects of radiotherapy and chemotherapy were more effectively treated when we used Korean oriental medical treatments. In addition, more Korean oriental medical experiments and clinical studies are needed in Korea, in the future.