• Composites Research
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• v.30 no.6
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• pp.338-342
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• 2017

In this paper, evaluation method of structural integrity of cylindrical composite lattice structures was conducted. A finite element analysis was used to evaluate the structural integrity of composite lattice structures. In order to verify the optimal finite element in the evaluation of the structural integrity, finite element models for cylindrical composite lattice structure were generated using beam, shell and solid elements. The results of the finite element analyses with the shell and solid element models showed a good agreement. However, considerable differences were found between the beam element model and the shell and solid models. This occurred because the beam element does not take into account the degradation of the mechanical properties of the non-intersection parts of cylindrical composite lattice structures. It was found that the finite element analysis of evaluation of structural integrity for cylindrical composite lattice structures have to use solid element.

• Journal of Biomedical Engineering Research
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• v.23 no.2
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• pp.119-130
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• 2002

The nonlinear finite element program has been developed to analyze the design performance of an artificial hip prosthesis and long term behavior of a treated femur with stems made of composite material after cementless total hip arthroplasty(THA). The authors developed the three dimentional FEM models of femoral bone with designed composite stem which was taken with elliptic cross section of 816 brick elements under hip contact load and muscle farce in simulating single leg stand. Using the program, density changes, stress distributions and micromotions of the material femoral bone were evaluated by changing fiber orientation of stems for selected manufacturing method such as plate cut and bend mold. The results showed that the composite materials such as AS4/PEEK and T300/976 gave less bone resorption than the metallic material such as cobalt chrome alloy, titanium alloy and stainless steal. It was found that increasing the long term stability of the prosthesis in the femur could be obtained by selecting the appropriate ply orientation and stacking sequence of composite.

• Journal of Fashion Business
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• v.21 no.2
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• pp.105-112
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• 2017

A string wallcovering is a kind of textile wallcovering which is made of cellulose fiber yarn laminated on base paper. Compared with normal paper or PVC wallpaper, a string wallcovering is preferred continually in the interior design market, as it is not only environmentally friendly but it also has less cost on mass production without the weaving process and has a natural visual effect, excellent functionality such as thermo keeping, permeability, sound absorption. However, in the dyeing process, it is not appropriate to use plenty of energy such as water, electricity, steam or chemicals considering the environmental trend and the government policy plenty of energy such as water, electricity, steam or chemicals. Currently, a string wallcovering is made of raw white yarn and padding with direct dye or pigment which includes toxic elements, especially the use of direct dye is restricted in a part of the developed country due to inclusion of azo. In this study, we researched dyeing based on cold pad batch dyeing of a string wallcovering with reactive dyestuff. The peel strength and bending depth test confirmed that the optimum adhesive type and spread amount improved the water resistance of the string wallcovering. Also, pad batch dyeing with optimum reactive dyestuff enhanced the color fastness to light and rubbing in dry and wet conditions. Additionally, for improvement of color fastness to rubbing in a wet condition, the additional treatment finishing without soaping process which is used water. The results of this study can be used as basic data for environmentally friendly and energy saving of the textile wallcovering.

• Journal of Plant Biology
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• v.35 no.3
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• pp.211-217
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• 1992

In order to elucidate the formation of reaction tissues during the transition from primary to secondary growth, the developmental anatomy was conducted in the first internode of Acer sacchan'num seedling in horizontal position. During the transition from primary to secondary growth, tension wood(gelatinous fiber) was gradually developed on the upper side only, And the tension wood formation in the upper side of the horizontal first internode proceeds acropetally from base to apical portion. Some of the anatomical features of tension wood start to be in the primary vascular tissue and a typical tension wood show during the secondary growth, Therefore, the procambium seems to respond to the gravity as well as vascular cambium. For this reason, both procambium and vascular cambium has to regard as the same meristem, On the other hand, the upper side vessels were longer than those of the lower side in the horizontal first internode. The lateral-wall pitting of vessel elements, however, showed no differences between upper and lower sides which have alternate type. The width and height of rayon the upper side of horizontal first internode was larger as compared with the lower side.r side.

• Korean Journal of Human Ecology
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• v.21 no.4
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• pp.791-803
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• 2012

This study intends to identify applicability of natural dye extracted from Aplysia kurodai, aiming to standardization of Aplysia kurodai natural dyeing through scientific validation by analyzing characteristics of pigment elements to review dyeability, colorfastness and antibacterial activity. Such material as silk fabrics that is animal fiber were used for this purpose, and derived following summarized results. UV/VIS spectrum analysis on the pigment of Aplysia kurodai that was extracted from purple gland showed that maximum absorbtion was near 540 nm. The silk fabric optimal dyeing can be achieved at a temperature of $55^{\circ}C$ with a colorant concentration of 5%. Dyed at $55^{\circ}C$ with interval of 10~90 minutes for identifying dye uptake over time to observed slow increase of dye uptake over time, and equilibrium occurred at 50 minutes. For dye uptake according to pH, while dye uptake was superior in acidity, it decreased rapidly in a base after pH 7. For color changes according to pH variation, it was reddish purple in acidity and was purplish red in a base. For color changes according to mordanting method, more clear color change had been obtained when process with aluminium pre-mordanting than non-mordanting and post-mordanting. The colorfastness to light, perspiration and washing was 1, 4~5, and 3~4 ratings respectively. The silk fabric dyed with Aplysia kurodai demonstrated excellent antimicrobial activity to Staphylococcus aureus and Klebsiella pneumoniae. The Aplysia kurodai can be used as a new colorant for the natural dyeing of silk.

• Journal of the Korea institute for structural maintenance and inspection
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• v.16 no.3
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• pp.99-108
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• 2012

In this paper, to intend anticorrosive effect and weight reduction of conventional reinforced concrete slab, lightweight concrete slab reinforced with glass fiber reinforced polymer(GFRP) bar was considered and some basic behaviour of the slab were investigated. Measurement of splitting tensile strength and fracture energy of the concrete, a number of flexural experiment of the slab, numerical analysis using nonlinear finite element analysis, and comparison of the experimental results to the numerical analysis, were conducted. As a result, even the weight of the lightweight concrete slab could be reduced by about 28% than the normal concrete slab, failure load of the lightweight concrete slab was 36% smaller than the normal concrete slab. Such a thing can be attributed to the lower axial stiffness and lower bond strength of GFRP bar. In the numerical analysis, to consider decreasing property of bond strength of the lightweight concrete, interface element was used between the concrete and the GFRP bar elements and this method was shown to be a better way for the numerical analysis to approach the experimental results.

• Journal of the Korean Home Economics Association
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• v.17 no.3
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• pp.13-21
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• 1979

The purpose of this study were : (1) to analyze the commercial sizes in Korea , (2) to investigate the designs and materials of one-piece dresses, and (3) to ascertain the prices and tendency to sale of dresses. A questionaire and the interviews with some producers were used for this study. The questionaire was made with many items after the pretest. For the statistical analysis, 99 dresses were used among 141 dresses which were examined. The observation of ten observers was made in markets(group A), department stores (group B), and commercial agents of manufacture (group C). The period of observation was from April 10 to May 4 , 1979. The results of this study indicated that : (1) According to makers , the commercial sizes in Korea were different. The sizes were based on only waist in group A , body measurements in group B, and either of them in group C. (2) In dress style, the box dresses were popular in three groups. (3) The type of sleeve in group A, B and C showed in following order : set in sleeve > dropped shoulder > raglan sleeve. (4) The most necklines were finished with collars. The shirtwaist collars were popular in group A and C and the flat collars in group C. (5) In dress material , cotton/polyester was popular in group A, wool in group B, and silk in group C. The use of natural fiber and color in three groups decreased in following order : C>B>A. (6) The prices of dresses were from 10,000 to 35,000 won in group A, form 23,8000 to 49, 800 won in group B, and from 12,500 to 90,000 won in group C. (7) In case of group C, the elements which had influence on sale were color, design, and price.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.1
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• pp.51.1-51.1
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• 2014

DOTIFS is a new multi-object Integral Field Spectrograph (IFS) being designed and fabricated by the Inter-University Center for Astronomy and Astrophysics, Pune, India, (IUCAA) for the Cassegrain side port of the 3.6m Devasthal Optical Telescope (DOT). The telescope is constructed by the Aryabhatta Research Institute of Observational Sciences, Nainital (ARIES). Its main scientific objectives are the physics and kinematics of the ionized gas, star formation and H II regions in nearby galaxies. It is a novel instrument in terms of multi-IFU, built in deployment system, and high throughput. It consists of one magnifier, 16 integral field units (IFUs), and 8 spectrographs. Each IFU is comprised of a microlens array and 144 optical fibers, and has $7.4^{\prime\prime}{\times}8.7^{\prime\prime}$ field of view with 144 spaxel elements with a sampling of 0.8" hexagonal aperture. The IFUs can be deployed on the telescope side port over an 8' diameter focal plane by x-y actuators. 8 Identical, all refractive, dedicated fiber spectrographs will produce 2,304 R~1800 spectra over 370-740nm wavelength range with single exposure. Currently, conceptual and baseline design review had been done, and is in the critical design phase with a review planned for later this year. Some of the components have already arrived. The instrument will see its first light in 2015.

• Resources Recycling
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• v.10 no.4
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• pp.34-41
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• 2001

A research was performed to evaluate a use of shredder residue to currently dispose of at landfills. Laboratory analyses were conducted to determine especially the fuel characteristics of shredder residue. For this aim, shredder residue was classified by the particle size as well as by the type of material and the content of Cl, S, ash, and calorific value were determined. Due to the chlorinated plastic content of shredder residue, mean concentration of Cl was found to exceed 4wt% except one sample while that of S was ranged from 0.25 to 0.39 wt%. As far as calorific value was concemed, plastic was observed to be more than 10,000 kcal/kg while wood/paper and fiber accounted for approximately 4,000 kcal/kg. Shredder residue was found to contain varying trace amounts of metal elements, including Fe of 6∼8.5 wt%. Hg and Cr(VI) were not detected, however, while Cd was contained as small as 0.0004-0.0009 wt%.

• Journal of the Korean Society for Nondestructive Testing
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• v.23 no.3
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• pp.237-245
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• 2003

Since the velocity is dependent on the fiber orientation in anisotropic composites, the application of traditional acoustic emission (AE) source location techniques based on the constant velocity to composite structures has been practically impossible. The anisotropy makes the source location procedure complicated and deteriorates the accuracy of the location. In this study, we have divided the region of interest(ROI) into a set of finite elements, taken each element as a virtual source, and calculated the arrival time differences between sensors by using the velocities at every degree from 0 to 90. The calculated and the experimentally measured values of the arrival time difference aye then compared to minimize the location error. The results from two different materials, namely AA6061-T6 and CFRP(uni-directional; UD, $[0]_{32}4$) laminate confirmed the practical usefulness of the proposed method.