• Computers and Concrete
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• v.11 no.6
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• pp.541-569
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• 2013

There is a wide variety of existing Genetic Algorithms (GA) operators and parameters in the literature. However, there is no unique technique that shows the best performance for different classes of optimization problems. Hence, the evaluation of these operators and parameters, which influence the effectiveness of the search process, must be carried out on a problem basis. This paper presents a comparison for the influence of GA operators and parameters on the performance of the damage identification problem using the finite element model updating method (FEMU). The damage is defined as reduction in bending rigidity of the finite elements of a reinforced concrete beam. A certain damage scenario is adopted and identified using different GA operators by minimizing the differences between experimental and analytical modal parameters. In this study, different selection, crossover and mutation operators are compared with each other based on the reliability, accuracy and efficiency criteria. The exploration and exploitation capabilities of different operators are evaluated. Also a comparison is carried out for the parallel and sequential GAs with different population sizes and the effect of the multiple use of some crossover operators is investigated. The results show that the roulettewheel selection technique together with real valued encoding gives the best results. It is also apparent that the Non-uniform Mutation as well as Parent Centric Normal Crossover can be confidently used in the damage identification problem. Nevertheless the parallel GAs increases both computation speed and the efficiency of the method.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.7
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• pp.2328-2333
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• 2010

A direct boundary element method(DBEM) is widely applied for various acoustic wave problems. But this method has numerically non-unique solutions around the eigenfrequencies of the interior Dirichlet problem for the region enveloped with the acoustic boundary. A CHIEF method had been generally adopted to resolve the non-uniqueness problem and a new technique called ICA-Ring method has been suggested recently. In this paper, the characteristics of two techniques for avoiding the non-uniqueness of DBEM are examined and numerical codes embodying both techniques are developed. Numerical calculations are also carried out for an uniformly pulsating sphere, of which the results are investigated by including the comparisons with theoretical solutions.

• Computers and Concrete
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• v.16 no.2
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• pp.287-309
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• 2015

FormWorks-Plus is a generalized public domain user-friendly preprocessor developed to facilitate the process of creating finite element models for structural analysis programs. The lack of a graphical user interface in most academic analysis programs forces users to input the structural model information into the standard text files, which is a time-consuming and error-prone process. FormWorks-Plus enables engineers to conveniently set up the finite element model in a graphical environment, eliminating the problems associated with conventional input text files and improving the user's perception of the application. In this paper, a brief overview of the FormWorks-Plus structure is presented, followed by a detailed explanation of the main features of the program. In addition, demonstration is made of the application of FormWorks-Plus in combination with VecTor programs, advanced nonlinear analysis tools for reinforced concrete structures. Finally, aspects relating to the modelling and analysis of three case studies are discussed: a reinforced concrete beam-column joint, a steel-concrete composite shear wall, and a SFRC shear panel. The unique mixed-type frame-membrane modelling procedure implemented in FormWorks-Plus can address the limitations associated with most frame type analyses.

• The Journal of the Korea institute of electronic communication sciences
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• v.18 no.1
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• pp.11-22
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• 2023

A radiating elements fault diagnosis method with simplified radiation pattern measurement procedure was presented for planar active phased array antenna system. For presenting the mentioned method, the technique for linear approximation based on the radiation characteristics of a planar array configuration and a technique for solving a unique solution problem that occur in process of diagnosing a fault in a radiating elements were presented. Based on the presented method and a genetic algorithm, experimental simulations were performed for radiating element defect diagnosis according to various planar active phased array antenna configurations. As a result, it was confirmed that the presented radiating element fault diagnosis method can be smoothly applied to planar active phased antennas having various configurations.

• Wind and Structures
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• v.34 no.3
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• pp.313-319
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• 2022

The resiliency of electricity transmission and distribution lines towards natural and man-made hazards is critical to the operation of cities and businesses. The extension of these lines throughout the country increases their risk of extreme loading conditions. This paper investigates a unique extreme loading condition of a 100-year old distribution line segment that passes across a river and got entangled with a boom of a ship. The study adopts the Applied Elements Method (AEM) for simulating 54 cases of the highly deformable structural behaviour of the tower. The most significant effects on the tower's structural integrity were found to occur when applying the load with components in all three of the cartesian directions (i.e., X, Y and Z) with the full capacities of the four cables. The studied extreme loading condition was determined to be within the tower's structural capacity, attributed to the shear failure of the anchor bolts, which acted as a sacrificing element that fails to protect the transfer of tensioning load to the supporting tower.

• Steel and Composite Structures
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• v.18 no.1
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• pp.255-271
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• 2015

This paper presents the natural frequency of a composite girder with corrugated steel web (CGCSW). A corrugated steel web has negligible in-plane axial stiffness, due to the unique characteristic of corrugated steel webs, which is called the accordion effect. Thus, the corrugated steel web only resists shear force. Further, the shear buckling resistance and out-of-plane stiffness of the web can be enhanced by using a corrugated steel web, since the inclined panels serve as transverse stiffeners. To take these advantages, the corrugated steel web has been used as an alternative to the conventional pre-stressed concrete girder. However, studies about the dynamic characteristics, such as the natural frequency of a CGCSW, have not been sufficiently reported, and it is expected that the natural frequency of a CGCSW is different from that of a composite girder with flat web due to the unique characteristic of the corrugated steel web. In this study, the natural frequency of a CGCSW was investigated through a series of experimental studies and finite element analysis. An experimental study was conducted to evaluate the natural frequency of CGCSW, and the results were compared with those from finite element analysis for verification purpose. A parametric study was then performed to investigate the effect of the geometric characteristics of the corrugated steel web on the natural frequency of the CGCSW. Finally, a simplified beam model to predict the natural frequency of a CGCSW was suggested.

• Journal of the Korean Society of Costume
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• v.67 no.3
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• pp.66-80
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• 2017

The headdress is one of the most important clothing characters in China, as it was used to distinguish the 55 minority groups in China. Each minority group has a unique headdress culture. Among the 55 minority groups, the Zang, the Yi, and the Miao focus their ethnic costumes on the headdress, and have a more distinctive headdress culture compared to be other nationality groups. The Yi is one of the minority groups that linvd in Southwest China. They usually lived in compact communities in Sichuan, Yunnan, and Guizhou provinces, as well as the Guangxi Zhuang Autonomous region. The total population of the Yi is the sixth largest among the 55 minority groups. Modern scholars believe that the Yi people are descendants of the ancient Qiang people, which is a group that lived in Northwest China six or seven thousand years before. It is believed that the Qiang went down to the southern part of China and allied with the aboriginals in that region, and this group of people became the Yi, Due to its long history, cultural background, and the large number of people and settlements, they have produced a unique costume culture. The women's headdress culture is considered to be the one of the most important characteristics of their costume culture. There are four forming element of the Yi women's headdress, religious faith, myths, geographical distribution and customs & festivals. The first three elements play an important role in the protection and spread of headdress, while the fourth element provides potential for the modern headdress development. Because of much influence factors, more than 100 types of Yi women headdresses have developed. Depends on categories, Yi woman headdress can be divided into kerchief, hat, fascinator and other accessories wore on the hand. This study investigated the development of the Yi women's headwear, and screened and analyzed representative Yi women accessories, such as the headscarf, hat, and fascinator. This analysis will provide basic materials for further studies of Yi women's headdress or costume.

• Journal of Korean Society of Rural Planning
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• v.18 no.4
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• pp.61-67
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• 2012

Recently, brick walls are being widely introduced in rural areas. Walls are a very important design element of space. However, most brick wall works do not consider the human psychological characteristics. The purpose of this study was to investigate psychological characteristics on brick wall bonds such as the stack bond, running bond, english bond, flemish bond, america bond. The results of the research can be summarized as follows: 1)There is no statistical difference of psychological evaluation results among student groups using the semantic differential scale method using 10 adjectives. 2)Stack bonds have an uninspiring, artificial, simple, restful, boring and ordered psychological characteristic. Running bonds have an uninspiring, restful and ordered psychological characteristic. America bonds have a unique and modernistic psychological characteristic. English bonds have a unique, modernistic, complex and chaotic psychological characteristic. Flemish bonds have no critical psychological characteristics. 3)The running bond earned the highest score in preference, while the stack bond scored the lowest. Employment of brick wall bonds on this study was not highly preferred, hence it is necessary to develop a new brick wall bond design. 4)In conclusion, the proper selection of brick wall bonds is very important and we should consider human psychological characteristics in the design of rural areas.

• Journal of the Korean Institute of Rural Architecture
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• v.16 no.1
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• pp.1-8
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• 2014

This study investigated the characteristics of the establishment of an architectural guideline which is an important element of a urbanscape plan in basic landscape plans established by four local governments(a county level) in Jeollanam-do since the enactment of the landscape law. The results were as follows. The guideline for landscape plan elements was closely associated with shapes, materials, harmony, and coherence. For the detailed guideline for landscape plan elements, an architectural guideline on the arrangement, height, facade, and roof shapes of buildings, which is one of important elements related to urbanscape, was similar in local governments, showing a standard and uniform tendency. It indicates the limitation of forming urbanscape to enhance local identity and unique features and complementary contents are needed. The color guideline was classified into base color, sub color, and accent color in consideration of local features. In particular, natural material color was commonly used for base and sub color in all local governments. Therefore, it is necessary to develop unique material color and distinctive local color for each region.

• Korean Institute of Interior Design Journal
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• v.17 no.2
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• pp.30-38
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• 2008

It has been stated that the outer skin of an architecture should be related to and express the interior programs. It was rather moral issue than practicality. In contemporary urban cities, this nicely-linked relationship between exterior and interior has become much more complex and, in many cases, is no more valid. It tends that contemporary architectural skin is somehow separately developed and has its own logic to be independent from what is inside. This research focuses on these sort of logical design process to make unique image of skin in which conceptual thinking, spatialization and materialization are mixed together. More specifically this study articulates' expandable patternization process' based on the notion that it has a crucial role to systematically construct an image of skin. Expandable patternization has a couple of stages to complete an architectural skin. The first element is a single unit and the second is organization or arrangement of units based on a logical process. Lastly, the third is spatialization after relating the skin to the interior programs as well as environmental surroundings. It is found that, although, in most related projects, the architect or designer has followed his or her own preference or design tendencies, many skin projects has based the given unique characteristics from the beginning. This study concludes that skin design is not just an image making, but has an important role to amalgamate various aspects of an architectural projects: programs, concept of architect, environment, structure as well as image.