• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.977-980
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• 2008

Recently, the study on the application of SCC(Self-Compacting Concrete) is actively underway, in order to solve the lack of flowability and the poor compacting which is one of the chronic problems of tunnel lining concrete. The aim of this study is that to verify the validity of the application of SCLC(Self-Compacting Lining Concrete) for tunnel lining concrete and to examine the characteristic of flowing and mechanics of SCLC in term of comparing before and after casting SCLC was developed by Packing Factor mix method and casted in field mix-design according to the condition of site and the characteristic of aggregate. Before casting, the tests of the capability of flowability and durability was performed by slump flow, air void and so on. Additionally, the slump flow loss is measured to evaluated the possibility of cast-in-place. Furthermore, considering on the first time SCLC casting applied to the tunnel lining in Korea, it is provided that the careful items and the correct way for construction when applied the SCLC on site.

• Smart Structures and Systems
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• v.17 no.1
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• pp.73-89
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• 2016

The stress dependence of ultrasonic wave velocity is known as the acoustoelastic effect. This effect is useful for stress monitoring if the acoustoelastic coefficient of a subject medium is known. The acoustoelastic coefficients of metallic materials such as steel have been studied widely. However, the acoustoelastic coefficient of concrete has not been well understood yet. Basic constituents of concrete are water, cement, and aggregates. The mix proportion of those constituents greatly affects many mechanical and physical properties of concrete and so does the acoustoelastic coefficient of concrete. In this study, influence of the water-cement ratio (w/c ratio) and the fine-coarse aggregates ratio (fa/ta ratio) on the acoustoelastic coefficient of concrete was investigated. The w/c and the fa/ta ratios are important parameters in mix design and affect wave behaviors in concrete. Load-controlled uni-axial compression tests were performed on concrete specimens. Ultrasonic wave measurements were also performed during the compression tests. The stretching coda wave interferometry method was used to obtain the relative velocity change of ultrasonic waves with respect to the stress level of the specimens. From the experimental results, it was found that the w/c ratio greatly affects the acoustoelastic coefficient while the fa/ta ratio does not. The acoustoelastic coefficient increased from $0.003073MPa^{-1}$ to $0.005553MPa^{-1}$ when the w/c ratio was increased from 0.4 to 0.5. On the other hand, the acoustoelastic coefficient changed in small from $0.003606MPa^{-1}$ to $0.003801MPa^{-1}$ when the fa/ta ratio was increased from 0.3 to 0.5. Finally, it was also found that the relative velocity change has a linear relationship with the stress level of concrete.

• Computers and Concrete
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• v.22 no.4
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• pp.419-437
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• 2018

The compressive strength of self-compacting concrete (SCC) containing fly ash (FA) is highly related to its constituents. The principal purpose of this paper is to investigate the efficiency of hybrid fuzzy radial basis function neural network with biogeography-based optimization (FRBFNN-BBO) for predicting the compressive strength of SCC containing FA based on its mix design i.e., cement, fly ash, water, fine aggregate, coarse aggregate, superplasticizer, and age. In this regard, biogeography-based optimization (BBO) is applied for the optimal design of fuzzy radial basis function neural network (FRBFNN) and the proposed model, implemented in a MATLAB environment, is constructed, trained and tested using 338 available sets of data obtained from 24 different published literature sources. Moreover, the artificial neural network and three types of radial basis function neural network models are applied to compare the efficiency of the proposed model. The statistical analysis results strongly showed that the proposed FRBFNN-BBO model has good performance in desirable accuracy for predicting the compressive strength of SCC with fly ash.

• Journal of Distribution Science
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• v.18 no.2
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• pp.17-28
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• 2020

Purpose: Human life is increasingly improved, so human needs are also growing more and more. One of the increasingly demanding industries is the fashion market. Fashion is an industry that produces essential items for human life, so manufacturers always need to know how to improve the relationship with customers, and make them repurchase. The study aims to discover the relationship between the factors that create a relationship with customers and the repurchase intention of designed fashion products. Research design, data, and methodology: The mix research method is applied to achieve research objectives. The qualitative research via the in-depth interview with 11 experts, and the quantitative research via the survey with 467 respondents was done in Ho Chi Minh city, the most developed city in Vietnam. Results: The research results point out that the fashion designer reputation, social media marketing, and the fashion store atmosphere have the positive impact on the relationship between the customer and fashion store, as well as the intention to repurchase of designed fashion products. In particular, customer relationship also affects the repurchase intention of designed fashion products positively. Conclusions: The study also proposed some managerial implications to develop a relationship with the customer and repurchase behavior of the customer in the fashion industry.

• KIEAE Journal
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• v.17 no.1
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• pp.43-48
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• 2017

Purpose: Building owners or residents have concerns to strive for energy-saving and environmental conservation by utilizing with eco-friendlier energy resources for their physical environment. In this paper, an algae façade system is proposed as an energy-friendly building component to improve energy productivity and indoor environmental quality, and this study aims at verifying alternative technologies for implementing building elevations that contain various colors equipped with algae façade systems and suggesting design guidelines to enhance both building performance and design values. Method: The color of algae is basically ranged about the saturation green, and it is hardly converted to other variations. Such a problem can be resolved through the artificial lights like LED (Light Emitting Diode) lamps to mix the color from the algae and buildings could possibly change the elevation in many ways under the influence of daylight. Result: As a result, the suggested system may increase the aesthetic aspect of the building in response to environmental changes. The system cannot possibly be applied for only new construction, but also it can be utilized with the existing buildings as well. The proposed system is expected to be applied not only a new construction and any existing buildings as well, and it will cover from the environmentally friendly energy generation in the industry to a new application system for increasing energy efficiency and the beauty of building envelopes.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.52 no.11
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• pp.536-543
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• 2003

In this paper, we describe a unique self oscillating and mixing (SOM) down-converter design using a modified defected ground structure (DGS). The proposed SOM converter is consisted of self-oscillator, which can produce negative resistance and select resonance frequency, RF matching circuit, and IF low pass filter. As the advantage of this SOM converter can mix LO and RF signals as well as inducing LO signal with only one active device. it is designed as a simple structure and the low cost. Also, there is easy advantage to be applied in RFIC/MMIC technology because it offers excellent phase noise performance in spite of using micro-strip structure. The LO signal for the proposed SOM converter is designed at 1㎓ and RF frequency was chosen to be 800MHz. The achieved conversion loss and phase noise performances of the implemented SOM converter are 15㏈ and -95dBc/Hz at 100KHz offset frequency respectively. The equivalent circuit parameters for DGS are extracted by using a three dimensional EM simulator and simple circuit analysis method.

• Journal of Distribution Science
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• v.11 no.11
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• pp.19-32
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• 2013

Purpose - This study examines the effects of art marketing management of the marketing mix in fashion, focusing on the cases of the leading global fashion brands in art marketing management. Research Design, Data, and Methodology - This study was implemented using the content analysis method. Criteria, including product differentiation, promotion strategies, store strategies, and social contributions, were based on previous research, brand promotional references, and critical reviews in newspapers or professional magazines for various cases of art marketing management by fashion brands. Results - To achieve product differentiation, art marketing management has borrowed images from artworks, and employed parodies and collaboration with artists; this has facilitated the pleasure derived from utilizing the artistic value of products. Promotion strategies were integrated with art performances, advertisements, and runway shows. Store strategies developed emotional feelings and a longing for brands among consumers. Reputational marketing of the social contributions made by corporations elevated the corporate brand image perceived by consumers. Conclusions - This study's findings revealed that consumers can derive emotional satisfaction through art marketing that seeks to profit effectively by stimulating consumers' emotions. From an economic perspective, a convergence of art and marketing plays an important role in profit-making and satisfying consumers' emotions.

• Journal of the Korea Concrete Institute
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• v.13 no.4
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• pp.346-353
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• 2001

This research investigates the mixture proportioning of waste newsprint paper fiber for thin-cement product. Waste newsprint paper fibers obtained through shredded mechanically by a dry process. Waste newsprint paper fiber reinforced cement composites was manufacted by slurry-dewatering method. The waste newsprint paper fiber reinforcement conditions (fiber mass fraction, level of substitution of virgin fibers, level of fiber beating) and processing variables (pressed, unpressed) are optimized through experimental studies and statistical analyses based on factorial design of experiments and analyses of variance. The optimized recycled waste newsprint paper fiber reinforced cement composites were technically evaluated. The results are shown to possess acceptable properties and strong potentials of the recycling of waste newsprint paper of the reinforcement of thin-cement products.

• KIEAE Journal
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• v.10 no.5
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• pp.23-30
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• 2010

The residence means a given place. It is repeated that process of overcome, protection, assimilation and adaptation has applied to environmental condition. Architecture is part of environment and various. Thus there are lots of types. We need the place with uniqueness, and it is suitable for biological and humanistic environment. The living space turned to be meaningful place with design, and people start to live with nature together. Therefore design restructures whole environment and makes people to be closed with nature. We have to understand nature of environment to connect one place with the other place, and people start to put down roots certain place. Coping with social needs, we have to develop the architectural alternative which can be applied to natural condition. This study suggest sound high-density urban residential model as it function social mix.

• Proceedings of the KIEE Conference
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• 2003.07c
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• pp.1958-1960
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• 2003

Here we describe a unique self-oscillating mixer (SOM) design using a modified defected ground structure (DGS) for down-converter. Proposed SOM is consisted of self-oscillator, which can produce negative resistance and select resonance frequency, and input/output matching filter. As the advantage of this SOM can be reused by module that mix signals with transistor that is used to oscillator, it is simply and low-costly designed Also, there is easy advantage to be applied in RFIC/ MMIC technology because it offers excellent high Q value in spite of using micro-strip structure. Designed self-oscillating frequency is 1.04GHz and RF frequency established is 0.8GHz. It was achieved 20dB conversion loss and phase noise of -95dBc/Hz at 100KHz offset frequency over intermediate frequency (IF). The equivalent circuit parameters for DGS are extracted by using a three dimensional EM simulator and simple circuit analysis method.