• Proceedings of the Korea Concrete Institute Conference
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• 2010.05a
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• pp.189-190
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• 2010

Yeoju-Bo is a large massive concrete structures that require the reduction of working period of construction. In this study, we optimized the mix proportion of internal/external concrete and physical properties like compressive strength, semi adiabatic temperature rise in laboratory. And we also performed thermal analysis to verify the thermal cracking. Lastly we measured the hydration heat and the thermal cracking in site to verify the safety of massive concrete structure.

• International Journal of Highway Engineering
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• v.11 no.1
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• pp.1-12
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• 2009

A new mix design procedure for cold in-place recycling using foamed asphalt (CIR-foam) has been developed for Iowa Department of Transportation. Some strengths and weaknesses of the new mix design parameters were considered and modified to improve the laboratory test procedure. Based on the critical mixture parameters identified, a new mix design procedure was developed and validated to establish the properties of the CIR-foam mixtures. As part of the validation effort to evaluate a new CIR-foam mix design procedure, dynamic moduli of CIR-foam mixtures made of seven different reclaimed asphalt pavement (RAP) materials collected throughout the state of Iowa were measured and their master curves were constructed. The main objectives of this study are to provide: 1) standardized testing procedure for measuring the dynamic modulus of CIR-foam mixtures using new simple performance testing (SPT) equipment; 2) analysis procedure for constructing the master curves for a wide range of RAP materials; and 3) impacts of RAP material characteristics on the dynamic modulus. Dynamic moduli were measured at three different temperatures and six different loading frequencies and they were consistent among different RAP sources. Master curves were then constructed for the CIR-foam mixtures using seven different RAP materials. Based upon the observation of the constructed master curves, dynamic moduli of CIR-foam mixtures were less sensitive to the loading frequencies than HMA mixtures. It can be concluded that at the low temperature, the dynamic modulus is affected by the amount of fines in the RAP materials whereas, at the high temperature, the dynamic modulus is influenced by the residual binder characteristics.

• Journal of the Korean Society of Clothing and Textiles
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• v.29 no.9_10 s.146
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• pp.1253-1264
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• 2005

The background, concept, and design characteristics of the Caports style, which comes into new domestic fashion trend of sportism, are discussed in this article. Analysis are performed with utilizing pictures, advertizements of fashion magazine such as Vogue Korea, Fashionbiz, Ceci, etc., and photographs from internet sites, domestic papers since 2002. The result of this study is as followings: New life style, arose from the change of social and cultural environment, such as increase in leisure time, fusion and well-being trend, begins to be reflected in caports style in the form of stress on utility and functionality. The caports style is a fusion style based on sports wear with character and fashion. And, it can be adapted as a sports wear and daytime wear. With respect to the form, it emphasizes healthy body line, and as for the material, it strikingly utilizes various and functional materials. It also shows active and cheerful image using bright color, and utilizes functional and decorative details such as line-tape, zipper, hood. The most important characteristic of the caports style is to present a new liberal style by mix & match, layering, and exposing

• The Research Journal of the Costume Culture
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• v.22 no.6
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• pp.873-889
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• 2014

The goals of this study are to analyze how fashion professionals' attitudes toward Grunge style have changed since the 1990s and to compare aesthetic features of 1990s Grunge style and the style since 2000. By searching Vogue and Women's Wear Daily articles from 1992 to 2014 according to the keyword "Grunge", three collections from the 1990s and 59 collections since 2000 were selected for analysis. Although Grunge collections of the 1990s were harshly criticized by critics and retailers as ugly, the more recent collections have been highly praised for both design and profitability. The common aesthetic features of Grunge style in the 1990s and beyond include loose silhouettes, mix-and-match layerings, plaid patterns, floral prints, and striped patterns. However, Grunge style since 2000 has new features such as ornate fabrics, handcrafted details, a formal and dressy look, and faux plaid flannel shirts in chiffon or organza. These features give the style a more luxurious, feminine, and refined appearance. The results of this study indicate that Grunge style of the 1990s changed high fashion beauty standards and today's designers and consumers prefer to mix various styles to create new ones. They typically do not consider the original spirit or identities of the varied styles.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.445-448
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• 2006

Mix design of C80A which is applied to the vertical members of The Burj Dubai Tower, the tallest building of the world, was performed so as to meet the requirements of rheological property, mechanical properties & construction sequences based on material analysis in Dubai, UAE. Experimental investigations were carried out to evaluate & optimize the quantities of total binders, the proportions of Micro Silica, Dune Sand & PFA, changes of S/a and the comparison of chemical admixture, etc. Approximately $65,000m^3$ of C80A concrete has been poured to the vertical members since 16-Apr-2006. In the actual application, it was showed that C80A has proper early strength achievement, excellent mechanical properties and satisfactory flowability & workability. The results of extensive site testing can be summarized that the average compressive strength at 28days is 98.8MPa, the average elastic modulus at 28days is 47.8GPa, the flow of concrete after pumping at the height of 250m (L72) was over 500mm.

• Computers and Concrete
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• v.23 no.2
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• pp.97-106
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• 2019

This paper describes the design of a new interlocking masonry system, the production of designed interlocking units and mechanical properties of interlocked masonry assemblages with mortar. In this proposed system, units have horizontal and vertical locks to integrate the units to the wall and have a channel to enable the use of horizontal reinforcements in the wall. Using these units, unfilled, filled or reinforced walls can be constructed with or without mortar. In the production of the interlocking units, it was decided to use foamed concrete. 12 trial productions have been carried out at different mix proportions to obtain the optimum concrete mix. At the end of the mentioned productions, the units were produced with foam concrete which is selected as the most suitable in terms of compressive strength and specific gravity. Then, axial compression, diagonal tension and bed joint shear tests were carried out to determine the mechanical properties of the interlocked masonry assemblages with mortar. Results from the tests showed that interlocks designed to strengthen the system against shear stresses by creating discontinuity throughout the joints have been successful to achieve their aim. Obtained data will enable structural analysis of walls to be constructed with these new units.

• International Journal of Highway Engineering
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• v.19 no.5
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• pp.77-88
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• 2017

PURPOSES : It is necessary to clarify the rheological properties of cement paste as a basic research in the development of mechanistic concrete mix design. The rheological properties of cement paste with different binder types, mix propositions, and with/without high range water reducers have been analyzed. METHODS : In this study, ordinary Portland cement, fly-ash, blast furnace slag, silica fume, and limestone powder were used as binders. The range of water-binder ratio was 0.3-0.5, and a total of 30 different mixes have been tested. The slump flow test, V-funnel test, and Dynamic Shear Rheometer (DSR) test were performed to analyze the rheological properties of cement paste. RESULTS : As a result of the slump flow test, it was found that the composition ratio of the binder contents greatly affected the paste flow when the high range water reducers were added. The results of V-funnel test showed that when the water-binder ratio was decreased without high range water reducers, the binder composition ratio had a large effect on the passing time of the V-funnel tester, but with high range water reducers the impact of the binder composition ratio was decreased. The slump flow and V-funnel have a certain relationship with the rheological factors (yield stress and plastic viscosity), but the correlation was not significant. Finally, we proposed the M-value considering the density and specific surface area of the binder. The correlation between rheological factors and M-value were better demonstrated than experimental values, but there is still a limit to predict the rheological factor in general mix design. CONCLUSIONS :In this study, the rheological properties of cement paste were analyzed. The binder type, composition ratio of binder, and with/without high range water reducers have combined to provide the complex effects on the rheological properties of cement paste. The correlation between the proposed M-value and rheological factor was found to be better than experimental results, but needs to be improved in the future.

• The Research Journal of the Costume Culture
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• v.26 no.3
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• pp.296-312
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• 2018

In this study, we analyzed the whole design of the necklace in detail, which reflects the artistic sense of handicraft in couture. The purpose of the study was to identify the characteristics of the design based on the analysis findings and to provide basic data to help fashion designers. The research method entailed analyzing trends in necklace design - viewed in fashion magazines and on websites - by year, season, brand, kind, material, color, and image. The identified necklace design characteristics were as follows. First, artistry and originality are dramatically expressed through the use of a broad range of materials. Second, due to the necklace's role as an object of perfect beauty, in a number of images, the necklaces were presented in convergence and contrast with overall costumes. Third, the dramatic effects of layering revealed a strong presence and individualized styling. Necklaces are created with diverse sculptures by realizing the creative imagination of fashion designers. Even though they looked a little different every year, there were designs in the collections constantly. Round shape and princess length were preferred. In particular, the mix type was used to express dramatic effect by focusing neck part in entire styling which different length of necklaces were layered and worn. As a result, it meets the needs of consumers who emphasize brand differentiation and diversity, and it is believed that the role of necessities in fashion will continue and it creates economic demand in the fashion industry.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.6
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• pp.751-757
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• 2011

Subminiature devices such as Lab-on-a-chip and p-TAS(Micro Total Analysis System) have been intensively studied in biotechnology and chemistry, In many cases, a micromixer was widely used to mix different solutions for synthesizing novel materials. However, in microfluidic system, there is generally a laminar flow under very small Reynolds number so it is difficult to mix each solution perfectly. To settle this problem, we propose a new mixing mechanism which generates a horizontal and vertical multi-mixing (HVM) flow for effective mixing within a short mixing section. We evaluated the proposed mechanism using CFD analysis, and the results showed that the HVM mechanism had a relative high-effectiveness comparing to the existing methods.

• Korean Journal of Computational Design and Engineering
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• v.11 no.5
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• pp.359-364
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• 2006

Industrial Agitators are used in various industrial fields where they are necessary to intimately mix two reactants in a short period of time. However, despite their widespread use, complex unsteady flow characteristics of industrial mixers are not systematically investigated. The present study aims for clarify unsteady flow characteristics induced by various impellers in agitator's tank. Impellers are Pitched blade turbine(PBT) types, Screw type and Rushton turbine type(RUT). In this study is numerical analysis of the Industrial agitator's Impeller types. The rotating speed of impellers fixed about 100RPM. Numerical analysis results show that differential flow characteristics of each type Impeller and Rushton turbine type(RUT) is suitable for mixing powder.