• Journal of Korean Society of Steel Construction
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• v.29 no.5
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• pp.389-400
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• 2017

Based on U-shaped composite beam, the new form of AU-composite beam were developed to create economical and efficient components reducing the cost and shortening the length of construction work. Because the U-shaped sections are open and needs to be fixed by topping concrete securely. Therefore, it is required to maintain the U-shaped sections in a structure and to work in the safe condition through construction. It also requires accessories that resist the horizontal shear force for synthesis between the top and bottom of the U-shaped section. To reinforce these shortcomings, a shear connector has been developed with various purposes of steel plate anchors. In this study, the steel plate anchors were directly tested and the shear force was evaluated by the horizontal shear force. The experiment was divided into two types, depending on the applicable deck plates. As a result of the experiment, the continuous type specimens showed greater resistance in both strength and displacement than the ones of stud anchor specimen. In discontinuous type case, due to shear simulations and simple element analysis, the less increase the ratio of width to height and the more shear strength decreased. Thus, the shear strength equation of the stud anchor was modified to suggest the new shear strength based on the testing results.

• Journal of the Korea Convergence Society
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• v.9 no.9
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• pp.309-317
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• 2018

The purpose of this study was to investigate the effect of bone age on physique and physical fitness in elementary school students. For this purpose, the structural equation model test was conducted based on the three-year longitudinal study. The results were as follows. First, bone age in boys and girls (1st~3rd grade) has a direct effect on the change of body size, but it does not affect the change of physical strength. Second, the bone age of the senior male students(4~6 grade) gave a direct effect on the change of physique, 50m running, and sit-up. On the other hand, it gave an indirect effect on push-ups, sitting basketball throws, and standing long jump. Third, the bone age of the female students(grades 4~6) affected directly on body size change, sit-up, side step and indirect effect on 50m running, half squat jump, and standing long jump. These results indicated that the evaluation of the bone age of the subjects should be included in the exercise ability evaluation items for the male and female students in elementary school over the fourth grade in relation to the myofunction.

• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.4
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• pp.10-21
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• 2014

The joint of prefabricated steel grid composite deck is composed of concrete shear key and high-tension bolts. The flexural and shear strength of the joint were experimentally evaluated only by the bending and push-out test of the joint element. In this study the lateral load transfer behavior of the joint in deck structure system is experimentally evaluated. Several decks connected by the joint are prefabricated and loaded centrically and eccentrically. In the case of centrically loaded specimens, the analysis results show that for the same loading step the rotation angle of the joint with 4 high-tension bolts is larger than the case of the joint with 9 high-tension bolts. Consequently, flexural stiffness of deck and lateral load transfer decrease in the case of specimen with 4 high-tension bolts. But, in the case of eccentrically loaded specimens, it is found that there are no significant differences in the load transfer behavior. The further analysis results about the structural behavior of the joint show that lateral load transfer can be restricted by the load bearing capacity of the joint as well as punching shear strength of the slab. Furthermore, considering that high-tension bolts in the joint didn't reach to the yielding condition until the punching shear failure, increase in the number of high-tension bolts from 4 to 9 has a greater effect on the flexural stiffness of the joint and deck system than the strength of them.

• Journal of Life Science
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• v.21 no.4
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• pp.521-528
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• 2011

The purpose of this study was to analyze the effects of Hatha Yoga exercise on the body composition, serum lipids, and health-related fitness of obese middle-aged women. The subjects in the Hatha Yoga exercise group (n=9) were 18 obese middle-aged women that trained for 16 weeks and a control group (n=9). Body composition, serum lipids, and health-related fitness were measured in all of the subjects before the start of the training program and at the end of the 16 weeks. The findings of this study were as follows. Body weight, %BF, BMI, WHR, VFA, TC, TG, LDL-C, FFA, and HOMA-IR significantly decreased, whereas LBM, HDL-C, grip strength, back strength, push-ups, sit-ups, Harvard step test, and sitting trunk flexion significantly increased in the Hatha Yoga exercise group after 16 weeks. Therefore, regular and continuous Yoga exercise was effective in improving body composition, serum lipids, and health-related fitness. Consequently, Yoga exercise could be effective for preventing cardiovascular disease caused by obesity in middle-aged women.

• Journal of Internet Computing and Services
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• v.13 no.4
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• pp.63-71
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• 2012

This paper presents a design and implementation of U-Seum(Ubiquitous Museum) system based on the LBS(Location Based Service) and mobile augmented reality technique. The mobile services under the smart space of the ubiquitous environments have been expanded in the various fields. In this study, we introduce U-Seum which supports tourists in the museum. U-Seum is developed by use of the position tracking technique based on Wi-Fi and mobile augmented reality. The GPS which is widely used in the position tracking has a difficulty to be utilized in the inside of the building because it requires the Line-of-Sight between a sender and a receiver. Therefore, in this paper, we develop a realtime tour-supported service through experience and evaluate the performance of the system in the world famous UNESCO's Hwa-Seong Museum by measuring the distance from the Wi-Fi signal which is suitable to track the position interior of the museum. U-Seum provides various push services such as mobile augmented reality service for explanation of the artifacts of the museum, game services and the statistics information of the tourist when the tourist approach a specific AP. U-Seum is developed in the Haw-Seong Museum by the support of the Swon Haw-Seong Cultural Foundation. With a field test, we prove that the excellence and expandability of the system.

• Management & Information Systems Review
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• v.38 no.3
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• pp.127-136
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• 2019

With frequent incidents of unethical practices and acts in organizations, organizational leaders need to understand some of the causes that facilitate such negative organizational behaviors to lessen the chances of unethical behaviors from occurring. In an effort to understand some of the causes of unethical behavior, this study looks at competitive atmosphere and results-focused performance evaluation as some of the influencing factors on employees' tendency to decide to behave unethically. Competition culture can spur unethical behavior and evaluation culture with emphasis on results-focused which can create a perception among employees of a narrow view of work and how it is defined. The argument of this paper is that such characteristics can create environment for unethical behaviors and serve as an added push upon employees to choose to behave unethically. Collection of survey results from those working in Busan area were used to test the hypotheses using regression. Data analysis showed that in organizational atmosphere that is overly competitive and results-focused can influence employees to behave unethically. Implications and future research suggestions are discussed in conclusions.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.6
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• pp.129-137
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• 2020

In performing the structural analysis, the foundation is considered to be a fixed end as a plastic hinge model. In this study, the displacements of the foundation, pier, and shoe were compared when the foundation modeled as a fixed end, a shallow foundation constructed on bedrock of 2m depth, and a pile foundation constructed in the 10m to 20m depth of bedrock. The shear force was also compared, and the probability of damage was calculated and compared for the critical condition. When calculated as a fixed end, the displacement of the foundation converged to 0mm, but the shallow foundation built on the bedrock with a depth of 2m caused relatively displacement, and the pile foundation constructed to contact the bedrock with a depth of 18m caused a larger displacement. In addition, it was analyzed that the displacement of the foundation, which is the lower structure, affects the displacement of the super structure, but the difference in shear force applied to the foundation was insignificant in the three cases. There was no difference between the shallow foundation and the pile foundation in the influence on the displacement of the top of the pier, but there was a big difference from the analysis assuming as a fixed end.

• Journal of the Korea Concrete Institute
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• v.26 no.2
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• pp.151-157
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• 2014

Since recently developed Ultra-High-Performance-Concrete (UHPC) provides very high strength, stiffness, and durability, many studies have been made on the application of the UHPC to bridge decks. Due to high strength and stiffness of UHPC bridge deck, the structural contribution of top flange of steel girder composite to UHPC deck would be much lower than that of conventional concrete deck. At this point of view, this study proposes a inverted-T shaped steel girder composite to UHPC deck. This girder requires a new type of shear connector because conventional shear connectors are welded on top flange. This study also proposes three different types of shear connectors, and evaluate their ultimate strength via push-out static test. The first one is a stud shear connector welded directly to the web of the girder in the transverse direction. The second one is a puzzle-strip type shear connector developed by the European Commission, and the last one is the combination of the stud and the puzzle-strip shear connectors. Experimental results showed that the ultimate strength of the transverse stud was 26% larger than that given in the AASHTO LRFD Bridge Design Specifications, but a splitting crack observed in the UHPC deck was so severe that another measure needs to be developed to prevent the splitting crack. The ultimate strength of the puzzle-strip specimen was 40% larger than that evaluated by the equation of European Commission. The specimens combined with stud and puzzle-strip shear connectors provided less strength than arithmetical sum of those. Based on the experimental observations, there appears to be no advantage of combining transverse stud and puzzle-strip shear connectors.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.8 no.1
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• pp.9-17
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• 2010

The LCC (Liquid Cadmium Cathode) structure to be developed for inhibiting the formation and growth of the uranium dendrite has been known as a key part in the electrowinning process for the simultaneous recovering of uranium and TRU (TRans Uranium) elements from spent fuels. A zinc-gallium (Zn-Ga) experimental system which is able to be functional in aqueous condition and normal temperature has been set up to observe the formation and growth phenomena of the metal dendrites on liquid cathode. The growth of the zinc dendrites on the gallium cathode and the performance of the existing stirrer type and pounder type cathode structure were observed. Although the mechanical strength of the dendrites appeared to be weak in the electrolyte and easily crashed by the various cathode structures, it was difficult to effectively submerge the dendrite into the bottom of the liquid cathode. Based on the results of the aqueous phase experiments, a lab-scale electrowinning experimental apparatus which are applicable to the development of LCC srtucture for the electrowinning process was established and the performance tests of the different types of LCC structure were conducted to prohibit the uranium dendrite growth on LCC surface. The experimental results of the stirrer type LCC structures have shown that they could not effectively remove the uranium dendrites growing at the inner side of the LCC crucible and the performances of the paddle and harrow type LCC structure were similar. Therefore a mesh type LCC structure was developed to push down the uranium dendrites to the bottom of the LCC crucible growing on the LCC surface and at the inner side of the crucible. From the experimental results for the performance test of the mesh type LCC structure, the uranium was recovered over 5 wt% in cadmium without the growth of uranium dendrites. After completion of the experiments, solid precipitates of the bottom of the LCC crucible were identified as an intermetallic compound (UCd11) by the chemical analysis.

• Journal of Intelligence and Information Systems
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• v.26 no.3
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• pp.149-169
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• 2020

"The Urban Renewal New Deal project", one of the government's major national projects, is about developing underdeveloped areas by investing 50 trillion won in 100 locations on the first year and 500 over the next four years. This project is drawing keen attention from the media and local governments. However, the project model which fails to reflect the original characteristics of the area as it divides project area into five categories: "Our Neighborhood Restoration, Housing Maintenance Support Type, General Neighborhood Type, Central Urban Type, and Economic Base Type," According to keywords for successful urban regeneration in Korea, "resident participation," "regional specialization," "ministerial cooperation" and "public-private cooperation", when local governments propose urban regeneration projects to the government, they can see that it is most important to accurately understand the characteristics of the city and push ahead with the projects in a way that suits the characteristics of the city with the help of local residents and private companies. In addition, considering the gentrification problem, which is one of the side effects of urban regeneration projects, it is important to select and implement urban regeneration types suitable for the characteristics of the area. In order to supplement the limitations of the 'Urban Regeneration New Deal Project' methodology, this study aims to propose a system that recommends urban regeneration types suitable for urban regeneration sites by utilizing various machine learning algorithms, referring to the urban regeneration types of the '2025 Seoul Metropolitan Government Urban Regeneration Strategy Plan' promoted based on regional characteristics. There are four types of urban regeneration in Seoul: "Low-use Low-Level Development, Abandonment, Deteriorated Housing, and Specialization of Historical and Cultural Resources" (Shon and Park, 2017). In order to identify regional characteristics, approximately 100,000 text data were collected for 22 regions where the project was carried out for a total of four types of urban regeneration. Using the collected data, we drew key keywords for each region according to the type of urban regeneration and conducted topic modeling to explore whether there were differences between types. As a result, it was confirmed that a number of topics related to real estate and economy appeared in old residential areas, and in the case of declining and underdeveloped areas, topics reflecting the characteristics of areas where industrial activities were active in the past appeared. In the case of the historical and cultural resource area, since it is an area that contains traces of the past, many keywords related to the government appeared. Therefore, it was possible to confirm political topics and cultural topics resulting from various events. Finally, in the case of low-use and under-developed areas, many topics on real estate and accessibility are emerging, so accessibility is good. It mainly had the characteristics of a region where development is planned or is likely to be developed. Furthermore, a model was implemented that proposes urban regeneration types tailored to regional characteristics for regions other than Seoul. Machine learning technology was used to implement the model, and training data and test data were randomly extracted at an 8:2 ratio and used. In order to compare the performance between various models, the input variables are set in two ways: Count Vector and TF-IDF Vector, and as Classifier, there are 5 types of SVM (Support Vector Machine), Decision Tree, Random Forest, Logistic Regression, and Gradient Boosting. By applying it, performance comparison for a total of 10 models was conducted. The model with the highest performance was the Gradient Boosting method using TF-IDF Vector input data, and the accuracy was 97%. Therefore, the recommendation system proposed in this study is expected to recommend urban regeneration types based on the regional characteristics of new business sites in the process of carrying out urban regeneration projects."