• Journal of Korean Society of Steel Construction
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• v.15 no.2
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• pp.117-124
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• 2003

Wind-induced motions, like acceleration for instance, often influence designs for high-rise buildings. As a consequence, correct assessment of natural frequency becomes important. The empirical expressions used to quantify this parameter at the design phase tend to yield values that are significantly different from each other. This paper is concerned with the natural periods of steel buildings. It describes the vibration measurement methods that were employed for testing buildings. This paper will also present reliable methods of assessing the natural period from ambient vibration tests. Data from measurements on 21 buildings in Seoul were provided while 21 buildings were tested by ambient vibration measurements to obtain the natural periods. While regression formulas of natural periods for steel-frarried tall buildings were suggested,the obtained formula was compared with the empirical expressions of structural standards and the Eigen-value analysis.

• Tunnel and Underground Space
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• v.7 no.4
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• pp.323-333
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• 1997

A rock mass is usually classified by the results of geological survey and laboratory tests on rock specimens in order to obtain the adequate properties for the numerical analysis. For these purposes a rock mass strength is estimated based on the empirical criterion proposed by Hoek and Brown and a modulus of deformation is taken with the empirical relations developed by Bieniawski, Serafim and Pereira. In addition, the $K_o$ value which is the ratio of the horizontal stress to the vertical stress is one of the most important input data in the numerical analysis. Its role on a tunnel stability analysis could be verified with the numerical results taken by a finite difference code or a distinct element code. However, a deduced value used to be applied for the $K_o$ value in most of tunnel designs, even though the patterns of stress tensor are variable with regions and depths. Thus in situ stresses were measured by a hydraulic fracturing technique on several tunnel sites and applied directly to the tunnel design for the enhancement of its precision. With those informations on in situ stresses, the safe design should be obtained economically on the road or subway tunnels.

• Proceedings of the KSME Conference
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• 2001.11b
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• pp.533-538
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• 2001

In general, shape optimization design of the flow system has done to obtain the effects, which are required in the engineering fields. Most of these designs are accomplished by empirical or numerical analysis. But, in empirical analysis case, it is difficult to obtain an optimal shape in the feasible design region. And, in numerical method case, it usually needs many design parameters, because of the required object-function. In this paper, we present a newly numerical analysis, the growth-strain method having only one design parameter. That optimizes a shape by distributing a design parameter such as dissipation energy to be uniformed in the flow system. Also, we apply this shape design process to the three-flow systems, and then we identify that the resulting shape approaches the known optimal shape in the numerical values. Consequently, we confirm that the proposed method is very efficient and practical in the shape optimization of the flow system.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.26 no.7
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• pp.945-950
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• 2002

Shape optimization of a flow system is done to obtain the required effects, in the engineering fields. Most of these designs are accomplished by empirical or numerical analysis. In empirical analysis, it is difficult to obtain an optimal shape in the feasible design region. And, in numerical method, it usually needs much calculation expenses for shape optimization, because of design sensitivity analysis. In this study, we used the growth-strain method having only one distributed parameter such as a design variable. It optimizes a shape by making a distributed parameter such as dissipation energy uniform in a flow system, and then applied to two-flow systems. In order to overcome the stability occurred in numerical analysis performed by Azegami, the equation of volumic strain has been modified. Also, the shapes were compared with the known optimal shapes for the flow systems. Consequently, we confirm that the modified growth-strain method is very efficient and practical in shape optimization of the flow systems.

• International Journal of Naval Architecture and Ocean Engineering
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• v.7 no.4
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• pp.699-707
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• 2015

The ice-resistance estimation technique for icebreaking ships had been studied intensively over recent years to meet the needs of designing Arctic vessels. Before testing in the ice model basin, the estimation of a ship's ice resistance with high reliability is very important to decide the delivered power necessary for level ice operation. The main idea of previous studies came from several empirical formulas, such as Poznyak and Ionov (1981), Enkvist (1972) and Shimansky (1938) methods, in which ice resistance components such as icebreaking, buoyancy and clearing resistances were represented by the integral equations along the Design Load Water Line (DLWL). The current study proposes a few modified methods not only considering the DLWL shape, but also the hull shape under the DLWL. In the proposed methodology, the DLWL shape for icebreaking resistance and the hull shape under the DLWL for buoyancy and clearing resistances can be directly considered in the calculation. Especially, when calculating clearing resistance, the flow pattern of ice particles under the DLWL of ship is assumed to be in accordance with the ice flow observed during ice model testing. This paper also deals with application examples for a few ship designs and its ice model testing programs at the AARC ice model basin. From the comparison of results of the model test and the estimation, the reliability of this estimation technique has been discussed.

• Journal of Korean Society for Quality Management
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• v.49 no.3
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• pp.359-374
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• 2021

Purpose: This study attempted to verify which factor affects the intention to use of the connected car that has recently emerged. Methods: Based on prior researches, this study derives the characteristics of connected car that affects user intention and designs research model for empirical analysis. A structured questionnaire was conducted for those who drive cars, and a total of 292 usable responses were collected and empirically analyzed using SPSS and PLS. Results: The results of this study are as follows; service quality, hedonic motivation, and social influence have a significant effect on perceived value, but system quality, information quality, user innovation, experience and facilitating condition did not. In addition, it was found that system quality, information quality, service quality, user innovation, facilitating conditions and social influence have a significant effect on satisfaction, but hedonic motivation and experience did not affect satisfaction. Conclusion: The findings of this empirical analysis have implications for effectively recognizing the value of connected cars based on the technology of information systems to users and establishing sustainable growth strategies for connected car producers and suppliers.

• Architectural research
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• v.23 no.3
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• pp.39-48
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• 2021

Inspiration plays an essential role in architectural design process that compels architects to bring their ideas into final product by engaging in creative thinking. The relation in between architecture and music has been one of combination throughout architectural history used as inspirations for façade's forms and shapes, space configurations and arrangements, and etc. Applying music in architecture produces creative and scientific design methods, provides attractions for visitors, and reflects the social and cultural identities and changes of the particular period. This research aims to analyze the correlations between architecture and music in depth, and examine the perception of musically inspired architecture by empirical study. Five buildings that applied musical rhythms were chosen for survey questionnaires in order to observe how people majoring in architecture, music, and other fields perceive musically inspired architecture differently by matching the music with the building that correlate to each other. By examining the reasons that the respondents have selected such music with a building from the questionnaires, the keywords are extracted and interpreted. The results showed that it is possible for people to perceive music from architecture, and that it is suitable to use music as a source of inspiration in architectural designs.

• Asia-Pacific Journal of Business
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• v.11 no.4
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• pp.37-48
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• 2020

Purpose - This study empirically investigates whether the risk property included in fat-tails of return distributions is systematic or unsystematic based on the devised statistical methods. Design/methodology/approach - This study devised empirical designs based on two traditional methods: principal component analysis (PCA) and the testing method of portfolio diversification effect. The fatness of the tails in return distributions is quantitatively measured by statistical probability. Findings - According to the results, the risk property in the fat-tails of return distributions has the economic meanings of eigenvalues having a value greater than 1 through PCA, and also systematic risk that cannot be removed through portfolio diversification. In other words, the fat-tails of return distributions have the properties of the common factors, which may explain the changes of stock returns. Meanwhile, the fatness of the tails in the portfolio return distributions shows the asymmetric relationship of common factors on the tails of return distributions. The negative tail in the portfolio return distribution has a much closer relation with the property of common factors, compared to the positive tail. Research implications or Originality - This empirical evidence may complement the existing studies related to tail risk which is utilized in pricing models as a common factor.

• Journal of the Korea Fashion and Costume Design Association
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• v.23 no.2
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• pp.67-78
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• 2021

This study aims to analyze how students' design work functions affect consumer attitudes and purchase intentions toward clothes designed by students, while exploring the moderating effect of price sensitivity in such a relationship. Data was acquired from 351 responses of an online questionnaire (www.sojump.com). A two-step approach was employed to analyze our hypotheses using structural equation modeling (SEM) in SPSS 22.0 and AMOS 22.0 statistical packages. First, significant empirical evidence was secured regarding the effects of design functions (assurance, fashion, camouflage, individuality, and comfort) on consumer attitudes toward clothes, which can lead to purchasing intention. Fashion, individuality, and comfort functions can enhance consumer attitude significantly, but assurance and camouflage have no significant influence. Among the functions, comfort has the greatest effect on consumer attitudes, indicating that when students market works as commodities, comfort should be highlighted in their designs. In this way, such products can draw the interest of many consumers. Second, empirical evidence showed that price sensitivity negatively moderates the association between attitude and purchase intention. Thus, design courses should be careful when setting student works' prices given consumer sensitivity. The optimization of the student works' cost structure can help minimize price sensitivity. Overall, the findings and their implications can serve as a basis for the commercial application of design curriculum works and provide feasible support for developing student design curriculum in the future.

• Science of Emotion and Sensibility
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• v.13 no.1
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• pp.91-102
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• 2010

This study investigates the dominant degree of product design factors through the process of change of design factors. The previous research suggested a concrete measurement method of dominant designs, but it did not investigate empirically the degree of dominance due to the limited data for changes of designs. In this research, thus, after collecting design data of mobile phones and we measured the dominance and structure change of the designs by year. The analyses showed the following two things. First, in design factors of mobile phone the dominance on the body form and the edge grows more and both of them as dominant design factors tend to converge into the rectangular body form and the round edge, respectively. Second, the dominance on other design factors(e.g. the button type, the open type, whether or not to have digital multimedia broadcasting(DMB) and video telephony functions, the combination of colors and the body color) increases and decreases; and hence, design levels tend to diverge. In conclusion, the measurement of dominance on product design factors contributes to marketing managers and designers who are required to establish a strategy for products under the rapidly changing circumstances of market. This research aims to provide those managers and designers with a guide line for a successful development of new product to prepare for the dominant design from this empirical study.