• Journal of the Korea Concrete Institute
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• v.16 no.3 s.81
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• pp.375-382
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• 2004

The compressive strength of concrete is used as the most basic and important material Property when reinforced concrete structures are designed. It has become a problem to use this value, however, because the control specimen sizes and shapes are different from every country. In this study, the effect of specimen sizes and shapes on compressive strength of concrete specimens was experimentally investigated based on fracture mechanics. Experiments for the Mode I failure was carried out by using cylinder, cube, and prism specimens. The test results are curve fitted using least square method(LSM) to obtain the new parameters for the modified size effect law(MSEL). The analysis results show that the effect of specimen sizes and shapes on ultimate strength is apparent. In addition, correlations between compressive strengths with size, shape, and casting direction of the specimen are investigated. For cubes and prisms the effect of placing direction on the compressive strength was investigated.

• Fashion & Textile Research Journal
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• v.16 no.1
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• pp.128-136
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• 2014

The virtual try-on technologies of the current level have limitations with material expression as well as some difficulties with commercialization. There are differences in simulation results and subjective evaluations perceived by consumers according to the types and physical characteristics of materials used in virtual try-on simulations. This study were to analyze the exterior clothing shapes and visual images from 3D virtual try-on simulations with materials whose drapability was differentiated and then test the accuracy of the expression of the drapability of the materials. The study carried out 3D virtual try-on simulations by selecting flared skirts as an item to best express differences in drapability along with five materials of different physical properties and offered some basic data for greater utilization of virtual try-on simulations by comparing and analyzing them with the exterior shapes and visual images of actual flared skirts. The analysis results of hemline shapes between actual and virtual try-on according to the types of materials showed no match among the quantitative items of exterior shapes factors. There were no significant differences in the visual images except for "soft" according to the simulation methods, which means that the items can serve as part of a scale for visual image comparison. It is necessary to reflect quantitative numbers regarding "drapability" proposed in the study simulation software and to continue to build a systematic database for virtual simulations by investigating and testing various materials.

• Structural Engineering and Mechanics
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• v.65 no.6
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• pp.679-687
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• 2018

In composite materials technology, the fiber-reinforced polymers (FRP) have opened up new horizons in infrastructural engineering field for strengthening existing structures and components of structure. The Carbon fiber reinforced polymer (CFRP) sheets are well suited for RC columns to this application because of their high strength to weight ratio, good fatigue properties and excellent resistance to corrosion. The main focus of present experimental work is to investigate effect of shapes on axial behavior of CFRP wrapped RC columns having same cross-sectional area and slenderness ratio. The CFRP volumetric ratio and percentage of steel are also adopted constant for all the test specimens. A total of 18 RC columns with slenderness ratio four were cast. Nine columns were control and the rest of nine columns were strengthened with one layer of CFRP wrap having 35 mm of corner radius. Columns confined with CFRP wrap were designed using IS: 456:2000 and ACI 440.2R.08 provisions. All the test specimens were loaded for axial compression up to failure and failure pattern for each shaped column was investigated. All the experimental results were compared with analytical values calculated as per the ACI-440.2R-08 code. The test results clearly demonstrated that the axial behavior of CFRP confined RC columns is affected with the change in shapes. The axial deformation is higher in CFRP wrapped RC circular column as compared to square and rectangular columns. Stress-strain behaviour revealed that the yield strength gained from CFRP confinement was significant for circular columns as compare to square and rectangular columns. This behaviour may be credited due to effect of shape on lateral deformation in case of CFRP wrapped circular columns at effective confinement action.

• Structural Engineering and Mechanics
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• v.75 no.4
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• pp.415-424
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• 2020

Recently, many structural damage detection (SDD) methods have been proposed to monitor the safety of structures. As an important modal parameter, mode shape has been widely used in SDD, and the difference of vectors was adopted based on sensitivity analysis and mode shapes in the existing studies. However, amplitudes of mode shapes in different measured points are relative values. Therefore, the difference of mode shapes will be influenced by their amplitudes, and the SDD results may be inaccurate. Focus on this deficiency, a multi-strategy SDD method is proposed based on the included angle of vectors and sparse regularization in this study. Firstly, inspired by modal assurance criterion (MAC), a relationship between mode shapes and changes in damage coefficients is established based on the included angle of vectors. Then, frequencies are introduced for multi-strategy SDD by a weighted coefficient. Meanwhile, sparse regularization is applied to improve the ill-posedness of the SDD problem. As a result, a novel convex optimization problem is proposed for effective SDD. To evaluate the effectiveness of the proposed method, numerical simulations in a planar truss and experimental studies in a six-story aluminum alloy frame in laboratory are conducted. The identified results indicate that the proposed method can effectively reduce the influence of noises, and it has good ability in locating structural damages and quantifying damage degrees.

• Clean Technology
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• v.14 no.4
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• pp.265-270
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• 2008

In this study, the flow and heat transfer of the aligned pin-fin array of the air cooling module for electronic packaging application were numerically analyzed with various fin shapes. The geometric cross-sectional shapes of pin-fins considered in this study were ellipse, wing and circle. The fins had same cross-sectional area and height, but they had different surface areas. As the results, the surface area, the heat transfer coefficient, and the heat transfer performance of pin-fins greatly depended on their shapes. Of the three types of pin-fins, the wing type pin-fin with suitable shape produced the best heat transfer performance. This result implies that the cooling capacity of the pin-fin cooler can be significantly enhanced only by the change of fin shape without increasing air flow-rate or fin density.

• Korean Journal of Human Ecology
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• v.17 no.5
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• pp.975-987
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• 2008

The purpose of this thesis is to conduct a thorough research on shoes of 2000s, understand the changes and analyze the differences and the characteristics of the shoe designs of the past and present in order to predict and indicate the future direction of the women shoe designs. The shoes of the millennium not only kept the old fashioned shapes but also showed futuristic shapes. With the increasing importance of shoes in fashion, shoes with various images were created. As far as the materials are concerned, natural materials and artificial materials were both used. The colors were vivid and the futuristic colors. On the other hand, pastel toned colors and romantic colors were used in many different designs and shapes regardlees of the seasons. Straps and hills differed from the oldies. Heavy decorations were added to strap shoes to form a whole new design and hills show geometrical platforms or the avantgarde like heights. Feminine images overwhelmed the shoe designs of the millennium. To elaborate, Pumps displayed feminine images the most for it showed a high frequency number regardless of the seasons. Shoes are presented in aesthetical perspective rather then functional or practical perspectives that are based on human nature. Cultural, social, environmental and some part religious factors had a great influence on the evolution on the shoes. Especially in the 2000s, future oriented concepts were implemented on shoe designs, resulting a wider range of expressiveness and in the end leading to a more creative shoe designing. Changes in shoe designs could be pointed out in many ways according to the shapes materials, colors, modeling of decorations or also with the diverting trends.

• Journal of the Korean Applied Science and Technology
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• v.33 no.1
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• pp.23-29
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• 2016

Zinc oxide of hexagonal wurzite, is known as n-type semiconductor. It has a wide band gap energy of 3.37 eV and large exciton binding energy of 60 meV. It can be widely applied to gas sensors, laser diodes, dye-sensitized solar cells and degradation of dye waste. The use of microwave hydrothermal synthesis brings a rapid reaction rate, high yield, and energy saving. Amine additives control the different particle shapes because of the chelate effect and formation of hydroxide ion. In this study, zinc nitrate hexahydrate was used as zinc precursor. In addition, ethanolamine, ethylenediamine, diethylenetriamine, and hexamethylenetetramine are used as shape control agent. The pH value was controlled as 11 by NaOH. The shapes of zinc oxide are star-like, rod, flower-like, and circular cone. In order to analyze physical, chemical, and optical properties of ZnO with diverse amine additives, we used XRD, SEM, EDS, FT-IR, UV-Vis spectroscopy, and PL spectroscopy.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.26 no.4
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• pp.181-192
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• 2014

Light-shelf is one of the most efficient natural lighting systems due to the improved function of the inflow level of the outdoor natural light. However, the existing research on the light shelf limits to the rectangular parallelepiped space, so do not provide sufficient data for various shapes of spaces. Thus, this study aims at deriving proper plan and relationship of the light shelf through its performance assessment depending on the indoor space shapes and utilizing them as basic data of light shelf design. The conclusions are as follows : 1) for 6m space depth, standard intensity of illumination satisfaction depth has shown 8.3%~26.3% improvement through the adjustment of the angle and width when installing light shelf compared to no light shelf installation; 2) $-30^{\circ}$, $-20^{\circ}$ and $-10^{\circ}$ light shelves set by this study play only as a blind regardless of the shape of ceiling on the summer solstice, and it is unsuitable; and 3) this study has derived proper plan of light shelf upon space shapes based on energy reduction and indoor evenness. The study results provide expanded data of the performance assessment of the light shelves according to the different space shapes and light shelf factors, which serves as a basis of the light shelves designing.

• Fashion & Textile Research Journal
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• v.5 no.3
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• pp.235-243
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• 2003

This study is to figure out where the current satisfaction with ready-to-wear clothes based on middle-aged women's body shapes is at and to propose basic considerations in its production for coming up with a better sizing system to maximize customer's satisfaction. The data obtained from measurement and questionnaire by 126 middle- aged (35-59) women which were located in Gwangju. Followings are summary of this research, 1)The satisfaction level with lower -wear is relatively lower-wear than that of upper-wear in most parts of body. 2) The results by way of putting score show three different groups. Group 1 has characteristics of front body silhouette in the small ratio of shoulder width/bust width, shoulder width/waist width and big ratio of shoulder width/hip width. And Group 3 has characteristics of front silhouette, small ratio of hip girth/thigh girth. Group 2 has a standard shape. 3) The satisfaction level with lower-wear based on middle-aged women's body shapes shows slight difference. In this category, Group 2 has higher satisfaction level than that of Group 1, while Group 1 has better shape than Group 3. 4) The items of clothes which should be considered current less satisfaction on their size and pattern are skirt and pants. In the meantime, specific body parts for the same criteria are hip girth, thigh girth. And the 43.7% of middle-aged women who responded to this study requires improvement on the fit of lower-wear.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.54 no.11
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• pp.508-514
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• 2005

In this paper, it was investigated the characteristics of PD(partial discharge) pulse shapes in oil and the possibility of TF(Time-Frequency) analysis for the discrimination of air corona in on-site PD measurement of oil transformers. For the purpose, single and multiple discharges combined with oil discharges and air corona were generated and measured by use of artificial models through the HFPD pulse detector and the oscilloscope. PD pulse shapes were different according to the type of defects, especially including air corona- pulses. Also, through the TF analysis, data clusters could be classified each other in the TF Map, even in the case of multiple discharges. Therefore, it is known that TF analysis could be aprlied for the improvement of on-site PD measurement in oil transformers.