• Journal of the Korea Concrete Institute
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• v.13 no.6
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• pp.584-592
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• 2001

The cracks are developed in reinforced concrete(RC) beams at the early stage of service load because of the relatively small tensile strength of concrete. The structural strength and stiffness are decreased by reduction of tensile resistance capacity of concrete due to the developed cracks. Using the fiber reinforced concrete that is increased the flexural strength and tensile strength at tensile part can enhance the strength and stiffness of concrete structures and decrease the tensile flexural cracks and deflections. Therefore, the RC beams used of the fiber reinforced concrete at. tensile part ensure the safety and serviceability of the concrete structures. In this work, analytical model of a dual concrete beams composed of the normal strength concrete at compression part and the high tension strength concrete at tensile part is developed by using the equilibrium conditions of forces and compatibility conditions of strains. Three groups of test beams that are formed of one reinforced concrete beam and two dual concrete beams for each steel reinforcement ratio are tested to examine the flexural behavior of dual concrete beams. The comparative study of total nine test beams is shown that the ultimate load of a dual concrete beams relative to the RC beams is increased in approximately 30%. In addition, the flexural rigidity, as used here, referred to the slope of load-deflection curves is increased and the deflection is decreased.

• Journal of Fashion Business
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• v.15 no.1
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• pp.103-114
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• 2011

This study is to provide basic information on clothing fitness necessary to develop apparel products for Korean companies that want to enter or have already made inroads into the Chinese market. In an effort to serve this purpose, a standard upper torso body model for Chinese women was established by applying the Rohrer Index and Size Designation of Clothes - Women of GB/T 1335.2-1997 to Chinese women in their 20s to determine body types and its characteristics. First, according to the result of applying the Rohrer Index to categorize body types, Type 1 showed the longest vertical body length and a short horizontal length with the lowest degree of flatness. Type 2 was a standard body type with a height of 158.73cm, weight of 53.02kg and the Rohrer Index of 1.32. Type 3 had a thick and flat body shape that had the highest degree of flatness and the shortest vertical length in its upper torso among all three types of body. Second, F-test was conducted on 4 distinctive body types obtained from comparing obesity scores to verify differences in body shapes for different degree of obesity. The test result indicated significant differences in 3 of the 4 body types and showed different structural components for different degree of obesity. Third, the result of comparing correlational distributions of body types and height range, and body types and degree of obesity for all and specified age groups revealed that about 33.30% of the body types appeared in Type2-A followed by 20.18% in Type1-A, 18.40% in Type2-Y and 7.91% in Type1-Y respectively. Body types and degree of obesity for two different age groups were most frequent in Type2-A. For the group of young women in their early 20s appeared the most in Type2-A, Type1-A, Type2-Y and Type 1-Y respectively and young women in late 20s were frequent in the order of Type2-A, Type2-Y, Type1-A and Type1-Y.

• Trans-
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• v.6
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• pp.97-127
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• 2019

This study investigated the specific effects of dance themed movies on dance students in their passion for dance and affect. The related data is generated by choosing a method of Convenience Sampling and used a sample of 112 dance students in high school of arts which located in Seongnam-si, South Korea. The dance students divided into 3 group of school year and also 2 group of gender. The dance themed movies which are used in this research are First Position, Billy Elliot and Mao's Last Dancer. Also, the dance students were asked to answer the survey which are based on the Self-administration. In order to obtain several findings below, Frequency analysis, Exploratory factor analysis, Reliability analysis, t-test, ANOVA, Correlation analysis and Linear structural relation model were applied to the gathered data using statistics utility SAS 9.4. First, there was a significant difference between the school years in the passion for dance and affect of students after watching movies. Second, there was a significant difference in students' affect depended on their majors (dance major is divided into three specialized major which are ballet, korean dance and modern dance). Third, there was a significant difference in the passion for dance and students' affect which is irreverent to their dance career (such as years they have learned dance). Forth, there was a significant difference in the passion for dance and negative affect of 'dance' students after watching movies. To summarize, the findings demonstrate that there is a partial difference, specially significant effects on their negative affect in the dance passion and affect of dance students depended on their characteristics after watching dance themed movies.

• Journal of Korean Society of Steel Construction
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• v.28 no.1
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• pp.23-34
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• 2016

Concrete filled steel tube system has two major advantages. First, the confinement effect of steel tube improves the compressive strength of concrete. Second, the load capacity and deformation capacity of members are improved because concrete restrains local buckling of steel tube. It does, however, involve workability problem of using stud bolts or anchor bolts to provide composite effect for larger cross-sections. While the ribs inside the columns are desirable in terms of compressive behavior, they cause the deterioration in load capacity upon in-plane deformation resulting from thermal deformation. Since the ribs are directly connected with the concrete, the deformation of the ribs accelerates concrete cracking. Thus, it is required to improve the toughness of the concrete to resist the deformation of the ribs. Welding built-up tubular square columns can secure safety in terms of fire resistance if the problem are solved. This study focuses on mixing steel fiber in the concrete to improve the ductility and toughness of the columns. In order to evaluate fire resistance performance, loaded heating test was conducted with 8 specimens. The behavior and thermal deformation capacity of the specimens were analyzed for major variables including load ratio. The reliability of heat transfer and thermal stress analysis model was verified through the comparison of the results between the test and previous study.

• Journal of Distribution Science
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• v.13 no.4
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• pp.65-76
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• 2015

Purpose - This article aims to present and test a model regarding franchisors' supporting activities that may positively influence franchisees' attitude toward the franchising headquarter and their own business performance. Moreover, the authors examine the moderating effect of competitive intensity between franchisee attitude and business performance. Most previous research focused on behavioral performance measurements such as satisfaction, trust, and commitment. There are few empirical studies that focus on financial performance data because it is difficult to determine a relational mechanism between behavioral and financial performance. Moreover, financial data is confidential and difficult to collect in many cases. However, this study measures financial performance (e.g., sales revenue per square meter) differently than most previous research, which is mostly focused on the behavioral performance measurements. Research design, data, and methodology - To test our hypotheses, we selected 137 franchisee managers who are running chains of one of the foremost bakery franchise brands in South Korea. This study carefully investigated the reliability, content validity, convergent validity, and discriminant validity of the proposed instrument by analyzing the data obtained from the samples. The data was analyzed using the AMOS structural equation modeling program. Results - The results indicated that: non-financial support activities (e.g., information exchange and communication) had a positive impact on the franchisee attitude toward the franchising headquarter. The franchisee attitude in turn had a positive effect on the headquarters' business performance. Furthermore, competitive intensity could enhance the relationship between franchisee attitude toward franchising headquarter and business performance in a local franchise market. However, financial support activities (e.g., rewards and promotional support) and training had no relationship with either franchisee attitude or business performance. Conclusions - This study provides some practical implications to franchisors in terms of franchise operation and store opening strategies. With respect to the franchise operation strategy, franchisors need to focus on non-financial rather than financial support. Most franchisees consider the necessity of financial support activities and not their sufficiency because these activities are specified in their franchise contract. In addition, it is important for franchisees to maintain a positive attitude for the franchise headquarters. The franchisees with a positive attitude for the franchisor can show a high degree of solidarity for various support activities, and it consequently determines franchisees' sales performance. In terms of franchise store opening strategy, this study suggests an additional criterion that can be considered in determining the location of direct and non-direct management stores (e.g., franchisees' stores). In this research, franchise stores located within high level of competitive intensity are shown to have a high relationship between franchisee attitudes of franchisor support activities and business performance compared to the franchisees located within low competitive intensity level. This result shows that opening non-direct franchise stores is more effective than direct stores in higher competitive market situations. Research contribution, implications, and further research directions are discussed at the end of the paper.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.9
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• pp.596-603
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• 2020

'Electro-Mechanical Brake (EMB) is a novel braking system for automobiles and railway vehicles, and research in this area is actively underway. The current braking system for railway vehicles generates a braking force using a pneumatic cylinder, but the EMB system generates the force through a combination of an electric motor and gears. In this study, the design of an EMB system that meets the domestic standards was conducted through the finite element modeling and fatigue analysis of an eccentric rotating shaft-based EMB system capable of generating a high clamping force. At this time, to improve the accuracy of fatigue analysis, three types of fatigue test specimens, which were subjected to the same heat treatment as the materials used in the prototype, were produced, and the fatigue tests were performed for each material. The fatigue properties (S-N curves) were obtained from the fatigue test results for each material and reflected in the analysis model. The results of fatigue analysis confirmed that the design of the EMB prototype could satisfy the maximum commercial braking/relaxation of 530,000 times, which was the endurance life condition for domestic railway vehicles. In addition, based on this design, a prototype will be manufactured, and endurance testing will be completed to demonstrate the durability characteristics of the developed prototype.

• Journal of Korean Society of Steel Construction
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• v.26 no.4
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• pp.323-334
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• 2014

In this paper, experimental program and associated numerical study were carried out to evaluate the fire resistance of unprotected concrete-filled rectangular steel tubular (CFT) columns subjected to the standard fire. The key testing parameters included the length effect, the load ratio, and the sectional dimensions of the CFT columns. Temperature distribution and axial deformation of the CFT column specimens were measured and analyzed. Rather early local buckling of steel tubes was observed in all the specimens. This caused subsequent load transfer from steel tube to concrete, and eventually triggered concrete crushing, or complete loss of the load bearing capacity of the column. This implies that the limit state of local buckling as well as overall flexural buckling should be incorporated in fire design procedure. As expected, the fire resistance time of specimen with higher load ratio consistently lessened. The prediction of fire resistance time of unprotected CFT columns based on the limiting steel temperature in current design codes or the formula proposed by previous studies is slightly conservative compared to the fire test results available. To establish the finite element analysis model that can be used to predict the thermal and structural behaviour of unprotected CFT columns in fire, the fully coupled thermal-stress analysis was also tried by using the commercial code ABAQUS. The numerical results showed a reasonable global correlation with the experimental results.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.39.2-39.2
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• 2011

The new and renewable energy today has a great interest in all countries around the world. In special it has need more limit of the fossil fuel that needs of low carbon emission among the social necessary conditions. Recently, the high-rise building demand the structural safety, the economic feasibility and the functional design. The high-rise building spends enormous energy and it satisfied the design in solving energy requirements. The requirements of energy for the building depends on the partly form wind energy due to the cladding of the building that came from the surroundings of the high-rise building. In this study of the wind energy, the cladding of the building was assessed a tentative study. The wind energy obtains from several small wind powers that came from the building or the surrounding of the building. In making a cladding the wind energy forms with wind pressure by means of energy transformation methods. The assessment for the building cladding was surrounded of wind speed and wind pressure that was carried out as a result of numerical simulation of wind environment and wind pressure which is coefficient around the high-rise building with the computational fluid dynamics. In case of the obtained wind energy from the pressure of the building cladding was estimated by the simulation of CFD of the building. The wind energy at this case was calculated by energy transform methods: the wind pressure coefficients were obtained from the simulated model for wind environment using CFD as follow. The concept for the factor of $E_f$ was suggested in this study. $$C_p=\frac{P_{surface}}{0.5{\rho}V^{2ref}}$$ $$E_c=C_p{\cdot}E_f$$ Where $C_p$ is wind pressure coefficient from CFD, $E_f$ means energy transformation parameter from the principle of the conservation of energy and $E_c$ means energy from the building cladding. The other wind energy that is $E_p$ was assessed by wind power on the building or building surroundings. In this case the small wind power system was carried out for wind energy on the place with the building and it was simulated by computational fluid dynamics. Therefore the total wind energy in the building was calculated as the follows. $$E=E_c+E_p$$ The energy transformation, which is $E_f$ will need more research and estimation for various wind situation of the building. It is necessary for the assessment to make a comparative study about the wind tunnel test or full scale test.

• Journal of the Korea Concrete Institute
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• v.29 no.1
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• pp.23-32
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• 2017

The joints between precast PSC slabs of the intermediate road slab in double deck tunnel are inevitably generated in the road traffic vehicle traveling direction. Therefore, it is important to make the behavior of parts on the joint in one piece. The imtermediate road slab system of double deck tunnel in great depth proposed in this study will be constructed with precast PSC slab in order to minimize the construction period. And the joint connection between the precast slab has been developed in two methods: the 'Transverse tendon reinforcement method' and 'High strength bolts connection method'. Also, the experiments were performed for the full scale model in order to evaluate the performance of the intermediate road deck slab with two type joints systems, the structural stability was verified through the F.E.M analsysis. The results of static loading test and F.E.M analysis investigated a very stable behavior of intermediate road deck slab in double deck tunnel applying the joint methods developed in this study, in the cracks and deflections to satisfy the design standards of Highway Roads Bridges (2011), it was determined that there is no problem even servicebility.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.5
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• pp.478-489
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• 2016

Recently, there has been increasing interest in the remodecycling options of idle spaces around the central city through the urban regeneration. Various studies to create new added value through this way are ongoing. This study aims to analyze the impact relationship and structure on the regeneration of idle space by types affecting the quality of residents' life and local economy revitalization. The hypothesis was verified by a suitability test for setting the hypothesis and statistical significance test from the PLS 3.0 package. The results of this study drew 6 hypotheses from a total of 11 on the 'idle space regeneration of economy based type of PLS-SEM' and 4 hypotheses from a total of 11 on the 'idle space regeneration of neighborhood regeneration type PLS-SEM'. The results can be summarized into several parts. First, if cultural aspects should be considered, the regeneration of idle space (economy-based type and neighborhood-regeneration type) could meet 2 parts, such as the quality of residents' life and local economy revitalization at the same time. Second, improving the 'physical aspects' only affects the 'idle space regeneration of the economy-based type of PLS-SEM'. Third, improving the 'social aspects' only affects the 'idle space regeneration of neighborhood regeneration type of PLS-SEM'. This study has significance in that it provides the empirical analysis for the regeneration of idle space and there are differences according to types of PLS structural model.