• Structural Engineering and Mechanics
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• v.55 no.6
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• pp.1261-1278
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• 2015

Due to their low intrinsic damping, stay cables in cable-stayed bridges have often exhibited unanticipated and excessive vibrations which result in increasing maintenance frequency and disruption to normal operations of the entire bridges. Mitigation of undesired cable vibration can be achieved by attaching an external damping device near the anchorage. High Damping Rubber (HDR) dampers have many advantages such as compact size, better aesthetics, easy maintenance, temperature stability, and cost benefits; therefore, they have been widely used to increase cable damping. Although a single damper has been shown to reduce cable vibrations, it is not the most effective method due to geometric constraints. This paper proposes the use of two HDR dampers to improve effectiveness and robustness in suppressing cable vibration. Oscillation parameters of the cable-dampers system were investigated in detail by modeling the stay cable as a taut string and each HDR damper as complex-valued impedance and by using an analytical formulation of the complex eigenvalue problem. The problem of two HDR dampers arbitrarily located along a cable is solved and the solution is discussed. Asymptotic formulas to calculate the damping ratios of the cable with two HDR dampers installed near the anchorage(s) are proposed and compared with the exact solutions. Further, a design example is presented in order to justify the methodology. The results of this study show that when the two HDR dampers are installed close to each other on the same end of the cable, some interaction between the dampers leads to reduced damping ratio. When the dampers are on the opposite ends of the cable, they are effective in increasing damping ratio and can provide better vibration reduction to multiple modes.

• Steel and Composite Structures
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• v.42 no.4
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• pp.427-446
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• 2022

Cutouts in the beams or plates are often unavoidable due to inspection, maintenance, ventilation, structural aesthetics purpose, and sometimes to lighten the structures. Therefore, there will be a substantial reduction in the strength of the structure due to the introduction of the cutouts. However, these cutouts can be reinforced with the different patterns of ribs (stiffener) to enhance the strength of the structure. The present study highlights the influence of the elliptical cutout reinforced with a different pattern of ribs on the stability performance of such stiffened composite panels subjected to non-uniform edge loads by employing the Finite element (FE) technique. In the present formulation, a 9-noded heterosis element is used to model the skin, and a 3-noded isoparametric beam element is used to simulate the rib that is attached around a cutout in different patterns. The displacement compatibility condition is employed between the plate and stiffener, and arbitrary orientations are taken care by introducing respective transformation matrices. The effect of shear deformation and rotary inertia are incorporated in the formulation. A new mesh configuration is developed to house the attached ribs around an elliptical cutout with different patterns. Initially, a study is performed on the panels with different stiffener schemes for various ply orientations and for different stiffener depth to width ratios (d_s/b_s) to determine an optimal stiffener configuration. Further, various parametric studies are conducted on an obtained optimal stiffened panel to understand the effect of cutout size, cutout orientation, panel aspect ratio, and boundary conditions. Finally, from the analysis, it can be observed that the arrangement of the stiffener attached to a panel has a major impact on the buckling capacity of the stiffened panel. The stiffener's depth to width ratio also significantly influences the buckling characteristic.

• Journal of the Korean Society of Clothing and Textiles
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• v.36 no.4
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• pp.456-471
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• 2012

This study creates a method with more scientific patterns for use in designing golfwear slacks patterns that better reflect the unique characteristics of body types for elderly women aged 60 or older. This study investigates (when designing human-engineering golfwear slacks for elderly women) the body types of elderly women and design slacks patterns suitable for golf actions in order to design golfwear slacks that show excellence in function and aesthetics as well as for exercise and everyday wear conditions. The study indicated that "total crotch length" was the design element for most considerations when manufacturing golf slacks. A survey on the production of golf slacks for elderly women aged 60 or older showed that the 6 firms participating have not produced an exclusive product for women 60 years of age or older and have only manufactured an enlarged size up to 85. All 6 firms participating replied "No" two the question "Do you produce in consideration of the body types of women over 60 years of age?" Polyester-polyurethane composites were the most widely used (among golf slacks materials) as spring-autumn applications.

• Journal of the Korea Fashion and Costume Design Association
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• v.18 no.2
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• pp.145-159
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• 2016

This study developed the learning criteria for Science, Technology, Engineering, Arts & Mathematics to establish the theoretical background of the education pursued by STEAM. The learning criteria was developed on a basis of 6 kinds of Technology Home Economics textbooks by 2009 Amended Curriculum, and the factors of STEAM were extracted according to related contents. From the results of this study, the unit 'Dress and Self-expression' assimilated T.E.A.M with learning related to clothing psychology, consumer behavior, fashion design, and Korean fashion. The unit 'eco-friendly clothing and fixing clothes' was found to assimilate S.T.E.A.M. with learning related to clothes science and dress structure. Accordingly we can understand this unit also consists of the S. T. E. A. M assimilation such as clothes science, fashion marketing, dress structure, dress aesthetics, design and so on. Both units 'dress and self-expression' and 'eco-friendly clothing and fixing clothes' were found to consist of suggesting situations, creative planning and emotional experience following the learning criteria of STEAM. Therefore, these units will be the basic material for developing STEAM programs centering upon 'Home Economics' among the curriculum.

• Journal of Internet of Things and Convergence
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• v.6 no.1
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• pp.17-22
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• 2020

This paper is about IoT(Internet of Things)-based smart trash can. In modern society, waste disposal creates several social problems. In particular, large floating populations cause a problem in the city center on weekends as the waste disposal capacity cannot keep up with the amount of waste discharged. There are problems such as stinks, unpleasant aesthetics, and insects caused by overflowing garbage. To solve this problem, a smart trash can was proposed. The proposed smart trash can provide a garbage compression function, an automatic opening and closing of the trash can lid, a display of the amount of garbage, and monitoring and control of the trash can. It is expected that the proposed 'smart trash can' can be usefully used for outdoor waste disposal with a large floating population.

• Journal of Korean Society for Quality Management
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• v.36 no.2
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• pp.59-66
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• 2008

Dental implant has recently become one of the most viable treatment options for regaining the oral function and dental aesthetics compared with conventional fixed or removable dentures. Dental implants vary in material, dimensions, geometries, surface properties, and interface geometries. It has been reported that there has been a proliferation of manufacturers who produce implants using various materials and surface treatments, and the dentist needs to select from over 2,000 different dental implants and abutments in a specific treatment situation. Unfortunately, however, no metrics have been specifically identified for the purpose of quality assessment and selection of an appropriate dental implant. This study aims to provide practical guidelines for quality assessment of dental implant based on clinical data. Like other medical devices and materials, the superiority related to specific characteristics of the dental implant needs to be verified through extensive clinical studies. The procedures of clinical monitoring for dental implants have been proposed along with a case study to exemplify the usefulness of clinical monitoring for the purpose of continuous quality improvement in medical industry.

• KIEAE Journal
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• v.15 no.2
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• pp.79-86
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• 2015

Purpose: The concept of the tectonic has researched to find out the identify of modern architecture. The meaning of traditional tectonic knowledge to emphasize structural joints and attention to detail in creativity has developed in various ways in contemporary architecture. The purpose of this study is to analyze the tectonic characteristics and architectural expressions of the light appeared in the works of Santiago Calatrava. Major features in his works could be found is to maximize structural beauties through deducing the architectural images from the nature and expressing the material properties and the kinetic structures, and thus, to ultimately create the functional space and form by connecting the light to the tectonic structure. Method: Accordingly, I tried to analyze the three works of Santiago Calatrava (the Milwaukee Art Museum, the Bodegas Ysios Winery and the City and Arts and Sciences) as following categories - the structural aesthetics, the expression of material properties, the relationship between he kinetic structures and the light. Result: According to the results of the study, Santiago Calatrava tried to create his own architectural aesthetic by combining structural tectonic with nature, material, regional place and culture. He also sought to express the tense and dynamic tectonic rather than the stable one in his works.

• Solar Energy
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• v.17 no.4
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• pp.35-43
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• 1997

An increase in the design of commercial buildings with daylighting is beginning to receive more attention, claimed by some as a second revolution in architecture. The benefits of daylighting may vary significantly because a characteristic of daylight is the way in which it varies. Indirect sunlight, however, received in the interior of a building after reflection, can serve a useful purpose as the main source of illumination. In a cloudy climate it can serve as an occasional welcome addition to the available skylight. Also, site constraints or surrounding urban context may necessitate using reflected light sources, or such sources may be an integral part of the overall design objectives and aesthetics of the proposed projects. When reflected sunlight is introduced into a space, its role in general illumination is what is of interest in this study. Results show that reflected sunlight may help the general illumination in almost same level of significance as daylight from diffuse sky. It is also summarized that the contribution of reflected sunlight to general illumination through the year round may be even and uniform regardless of the season. Consequently, introduction of reflected sunlight should be regarded as one of the successful means to enhance the visual environment in quantitative and qualitative way.

• Journal of Korean Society of Rural Planning
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• v.25 no.4
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• pp.129-149
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• 2019

This study is to give a three-dimensional view of the concept of rurality and ruralness in terms of time-span, perceived object and awareness level. In the precedent studies ruralness or rurality has been approached as the category of usefulness resources called amenity. This overlooked the perceived representation, institutional reference and rurality of ideological values. Rurality appears as a cumulative representation of being rural from the past to the present, but ruralness exists as a desirable form or value for the future. Through this study, it has been analyzed that ruralness consists of six realms such as environment, community, self-reliance, aesthetics, enjoyable amenity and settlement, and of three or four sub-realms by each amounting to 20 in total. According to the vocabulary listing by the survey to 30 experts, rurality for the past-present is mainly imagined as of natural environment, agriculture, landscape, and community history, while ruralness for the future is frequently described as of communities, settlement and self-reliance by number of references. Through the vocabulary extraction, 17 words in the level of mid-conception are induced including ecology, comfort, history, agriculture, landscape, place, culture, convenience, etc. In conclusion the concept of ruralness along with rurality could be organized into three different layers of perception consisting of representation, norms and usefulness.

• Journal of the Korean Society of Industry Convergence
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• v.13 no.3
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• pp.161-168
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• 2010

Recently, bridges have been momenttous as not only regarding function but also concerning aesthetics. However, when beauty is considered in the bridge, it is also essential that stability and economics be considered. Besides, when considering stability, an arch bridge is one of the most stable structures. The most important element is a rise ratio when regarding beauty and economics of arch bridges. The effect of dead load and DB24 load have been considered to decide proper rise ratio. Therefore, in this study, examined the value of moment, displacement and member forces, in the variation of the rise ratio of arch bridges. The most optimum shape of Nielsen arch bridges has determined by analyzing member forces, moments and displacement with parameters of rise ratio and angle of vertical members. By comparison between values, the hanger types have been also considered to derive the optimum shape of Nielsen arch bridge.