• Journal of Korean Society of Steel Construction
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• v.13 no.6
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• pp.651-659
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• 2001

The main purpose of this paper is to present an analytical method for free vibration of stepped horizontally curved members on two-parameter elastic foundation. The ordinary differential equations governing the free vibration of such beams are derived as non-dimensional forms including the effects of rotatory inertia and shear deformation. The governing equations are solved numerically for the circular, parabolic, sinusoidal and elliptic curved beams with hinged-hinged, hinged-clamped and clamped-clamped end constraints. As the numerical results, the lowest four natural frequency parameters are presented as the functions of various non-dimensional system parameters. Also the typical mode shapes are presented.

• Journal of Fashion Business
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• v.14 no.4
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• pp.41-57
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• 2010

DongDaeMoon fashion retail market, or so-called the new western market, has been playing an important role in DongDaeMoon area's success from 1997 to early 2000's. However, the unique and successful fashion merchandising system of DongDeaMoon retail market has been seriously threatened by consumer need changes as well as by an increased competition from new types of retail stores such as discount stores and online shopping malls. Moreover, its performance has been deteriorated due to the increased number of undifferentiated, small and medium-sized retail stores within the area. In this paper, attempts are made in building revitalization strategies for DongDeaMoon fashion retail market on the basis of analyzing fast fashion and consumers. As results, we found that DongDaeMoon fashion retail market needs cooperated area management plan from related market members. This will help DongDaemoon's image change from deal-oriented market to relationship-oriented market with consumers. Through Focus Group interview, we found DongDeaMoon fashion retail market is confronted with insufficient shopping infrastructure and new challenge from global fast fashion brand. Moreover, to overcome this situation, consumers require repaired communication activities by DongDeaMoon fashion market members on consumer relationship management basis. At the end, this paper try to provide strategic implications for DongDeaMoon fashion retailers.

• Wind and Structures
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• v.31 no.3
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• pp.185-196
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• 2020

A method to reduce the wind pressure at the leading edge of a noise barrier was investigated by gradually lowering the height of a member added to the end of the noise barrier. The shape of the lowered height of the added member was defined by its length and slope, and the optimal variable was determined in wind tunnel testing via the boundary-layer wind profile. The goal of the optimal shape was to reduce the wind pressure at the leading edge of the noise barrier to the level suggested in the Eurocode and to maintain the base-bending moment of the added member at the same level as the noise-barrier section. Using parametric wind tunnel investigation, an added member with a slope of 1:2 that protruded 1.2 times the height of the noise barrier was proposed. This added member is expected to simplify, or at least minimize, the types of column members required to equidistantly support both added members and noise barriers, which should thereby improve the safety and construction convenience of noise-barrier structures.

• Journal of Engineering Education Research
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• v.13 no.3
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• pp.18-33
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• 2010

This paper describes two capstone senior design courses for the Mechanical Engineering program at University of the Pacific. The first course taught in the Fall semester is entitled "Engineering Design/Senior Project I." The second course taught in the Spring semester is entitled "Engineering Design/Senior Project II." All Mechanical Engineering students with senior standing are required to take these two classes in this sequence. At the end of every Spring semester, industrial advisors are invited to assess the final senior projects during an annual Senior Project Day. This assessment is performed using the Program Outcomes and Program Educational Objectives established for Pacific's Mechanical Engineering program. Since all Mechanical Engineering students are required to complete senior projects, this is a 100% evaluation process. After the evaluations are done, the data sets are compiled and reviewed by the faculty for assessment purposes. It is important to note that the industrial advisors perform the evaluations, but the faculty members assess the information to determine if modifications need to be made to the program or courses. In addition to the senior project evaluations, general feedback from Mechanical Engineering Industrial Advisory Committee (MEIAC) members is also useful for the outcomes-based assessment process in addition to the definition and evaluation of Program Outcomes and Program Educational Objectives.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05a
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• pp.479-482
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• 2005

The concrete box girder members are extensively used as a superstructure in bridge construction. The load carrying capacity of concrete box girders in lateral direction is generally influenced by the sizes of haunch and web. The internal upper decks are restrained by the webs and exhibit strength enhancement due to the development of aching action. The current codes do not have generally consider the arching action of deck slab in the design because of complexity of the behavior. However, there are significant benefits in utilizing the effects of arching action in the design of concrete members. The main objective of this paper is to propose a rational method to predict the ultimate load of deck slab by considering various haunch sizes and web restraint effect of concrete box girder bridges. To this end, a comprehensive experimental program has been set up and seven large-scale concrete box girders have been tested. A transverse analysis model of concrete box girders with haunches is proposed and compared with test data. The results of present study indicate that the ultimate strength is significantly affected by haunch dimension. The increase of strength due to concrete arcing action is reduced with an increase of prestressing steel ratio in laterally prestressed concrete box girders and increases with a larger haunch dimension. The proposed theory allows more realistic prediction of lateral ultimate strength for rational design of actual concrete box girder bridges.

• Structural Engineering and Mechanics
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• v.69 no.4
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• pp.417-426
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• 2019

Buckling is one of the major causes of failure in thin-walled plate members and the presence of cracks with different lengths and locations in such structures may adversely affect this phenomenon. This study focuses on the buckling stability assessment of centrally and non-centrally cracked plates with small-, intermediate-, and large-size cracks, and different aspect ratios as well as support conditions, subjected to uniaxial compression. To this end, numerical models of the cracked plates were created through singular finite element method using a computational code developed in MATLAB. Eigen-buckling analyses were also performed to study the stability behavior of the plates. The numerical results and findings of this research demonstrate the effectiveness of the crack length and location on the buckling capacity of thin plates; however, the degree of efficacy of these parameters in plates with various aspect ratios and support conditions is found to be significantly different. Overall, careful consideration of the aspect ratio, support conditions, and crack parameters in buckling analysis of plates is crucial for efficient stability design and successful application of such thin-walled members.

• International Journal of High-Rise Buildings
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• v.7 no.4
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• pp.313-325
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• 2018

Concrete-filled steel tubular (CFST) members are commonly used as composite columns in modern construction. However, the current guidelines for members' fire design (EN1994-1-2) have been proved to be unsafe in case the relative slenderness is higher than 0.5. In addition, the simplified design methods of Eurocode 4 are limited to circular and square CFST columns, while in practice columns with rectangular and elliptical hollow sections are being increasingly used because of their architectural aesthetics. In the last years a large experimental research has been carried out at Coimbra University on the topic. They have been tested concrete filled circular, square, rectangular and elliptical hollow columns with restrained thermal elongation. Some parameters such as the slenderness, the type of cross-section geometry as well as the axial and rotational restraint of the surrounding structure to the column have been tested in order to evaluate their influence on the fire resistance of such columns. In this paper it is evaluated the influence of the boundary conditions (pin-ended and semi-rigid end-support conditions) on the behavior of the columns in case of fire. In these tests it could not be seen a marked effect of the tested boundary conditions but it is believed that the increasing of rotational stiffness increases the fire resistance of the columns.

• The Korean Journal of Health Service Management
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• v.13 no.3
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• pp.39-51
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• 2019

Objectives: This study aimed to investigate the effect of satisfaction among convalescent hospital staff members on patient safety and quality of care after the certification of the medical institution. Methods: A survey was conducted on seven convalescent hospitals in Gwangju, South Jeolla Province, and North Jeolla Province, which were certified as medical institutions for convalescent hospitals by the end of May 2017, The study period lasted from July 24, 2017 to August 22, 2017. Results: There was a statistically significant correlation between staff member satisfaction and patient safety and quality of care (r = 0.586, p<0.001). Regression analysis showed that staff member satisfaction (${\beta}=0.531$, p<0.001) had a statistically significant effect on patient safety and quality of care and showed 46.9% explanatory power. Conclusions: The satisfaction of the convalescent hospital staff after the certification of the medical institution positively affected patient safety and quality of care.

• Structural Engineering and Mechanics
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• v.77 no.6
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• pp.735-744
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• 2021

In recent years, the use of new materials and technologies with the aim of developing high-performing and cost-effective structures has greatly increased. Application of high-strength concrete (HSC) has been found effective in reducing the dimensions of frame members; nonetheless, such reduction in dimensions of structural elements in the most cases may result in the lack of accountability in the tolerable drift capacity. On this basis, strengthening of frame members using fiber reinforced polymers (FRPs) may be deemed as an appropriate remedy to address this issue, which albeit requires comprehensive and systematic investigations. In this paper, the performance of properly-designed, two-dimensional frames made of high-strength concrete and strengthened with Carbon Fiber Reinforced Polymers (CFRPs) is investigated through detailed numerical simulation. To this end, nonlinear dynamic time history analyses have been performed using the Seismosoft software through application of five scaled earthquake ground motion records. Unstrengthened (bare) and strengthened frames have been analyzed under seismic loading for performance assessment and comparison purposes. The results and findings of this study show that use of CFRP can be quite effective in seismic response improvement of high-strength-concrete structures.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.1433-1439
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• 2009

Best value is the ultimate goal of the owner and can thus have diverse meanings according to the project characteristic, owner's purpose, user groups' payment capability, etc.. Recently, resettlement problems of the marginalized members in the urban regeneration area have been issued in Korea because they have no capability to purchase (or lease) redeveloped housing (or apartment). It means that a minimized production cost for reducing supply price of housing is a key factor in establishing the best value of the marginalized members. The lowest-price bidding system serves the purpose of ensuring a minimized production cost, but due to the low-cost investments, it creates various problems, such as sloppy construction, lowered quality, an increased LCC, and worsening profitability for builders. Thus, to help them resettle, it is necessary to supply affordable housing geared towards a certain appropriate quality and minimum construction costs. Towards this end, this study aimed to propose a cost reduction bidding system based on a technical proposal. The proposed technical-proposal-based cost reduction bidding system consists of the following components: work-unit-based, project-unit-based, and construction-period-reducing technical proposals. These components are evaluated to select the best bidder for a given project. The technical proposal based cost reduction bidding system proposed herein is expected to provide facilities with appropriate supply prices and appropriate quality levels, to bolster the technological competitiveness of builders.