• Journal of the Korean GEO-environmental Society
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• v.19 no.7
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• pp.5-11
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• 2018

Instead of a single pile, group piles are usually used for the pile foundation. If the earthquake occurs in the ground where group piles are installed, dynamic behavior of group piles are affected not only by interaction of piles and the ground movement but also by the pile cap. However, in Korea, the pile cap influence is not taken account into the design of group piles. Research on dynamic behavior of group piles has been performed only to verify interaction of piles and the ground and has not considered the pile cap as a factor. In this research, 1g shaking table model tests were performed to verify the thickness of the pile cap affects dynamic behavior of group piles that were installed in the ground where the earthquake would occur. The test results show that, as thickness of the pile cap increased, acceleration and horizontal displacement of the pile cap decreasd while vertical displacement of the pile cap increased. The results also showed that, among the group files tested, acceleration, horizontal displacement, and vertical displacement of the bearing pile are smaller than those of the friction pile.

• Composites Research
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• v.26 no.4
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• pp.207-212
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• 2013

In this study, the thickness optimization for uni-directional (UD) glass fiber reinforced polymer (GFRP) laminates of the spar cap of composite tidal blades was performed under the tip deflection constrains. The spar cap was composed of GFRP composites and carbon fiber reinforced polymer (CFRP) composites. The stress distributions in the blade as well as its material costs for the optimized results were additionally investigated. The optimized thickness was obtained by interacting a sequential quadratic programming (SQP) algorithm and an ABAQUS software to calculate an objective function. It was confirmed that the thickness of UD GFRP increased with a decrease of the restrained tip deflection when a thickness of UD CFRP laminates was constrained to 9 mm. The weight of the optimized spar-cap increased up to 96.2% while the maximum longitudinal tensile stress decreased up to 24.6%. The thickness of UD GFRP laminates increased with a decrease of the thickness of UD CFRP laminates when the tip deflection was constrained to 126.83 mm. The weight increased up to 40.1%, but the material cost decreased up to 16.97%. Finally, the relationships among the weight, internal tensile stress, and material costs were presented based on the optimized thicknesses of the spar cap.

• Journal of the Korean Geotechnical Society
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• v.23 no.9
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• pp.39-49
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• 2007

The load deformation behavior of the cap-pile-soil system is investigated, based on numerical analysis. Special attention is given to consideration of pile cap flexibility. Rigid pile cap analysis and flexible cap analysis were conducted for comparison. A numerical method that takes into account the coupling between the rigidities of the piles, the cap, and the column has been introduced to analyze the response of pile group supported columns. The prediction of the lateral loads and bending moments in the pile cap is much more conservative for a flexible cap than for a rigid cap.

• Journal of the Korean Home Economics Association
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• v.41 no.8
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• pp.201-212
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• 2003

This study aims to improve the comfort and fit of womens swimsuits. Based on the results of the survey, trial suits were designed. In terms of the breast cap, there are five variations based on the feature, size, and thickness and two variations according to the connection mode of the cap. Total 17 trial swimsuits were made, ease of movement and wearing comfort were evaluated. The results of this study were as follows: 1. In terms of movement according to the type of breast cap, the round type shelved much less movement than the triangular type at the lower part of the cap. According to size, the cap that was manufactured on the basis of brassiere cup size showed much less movement than the ordinary cap size in the same round type of cap. In terms of the connection mode between breast caps and swimsuits, there was less cap movement when they were connected by power nets compared to the ordinary models which were connected by conventional rope. 2. Analysis of the differences in wearing comfort. The round type proved to be more convenient than the triangular type at the lower circumference of the caps, the power net collection was rated more positively by the respondents.

• YAKHAK HOEJI
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• v.33 no.5
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• pp.312-318
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• 1989

Microcapsule of Propranolol HCl with Cellulose Acetate Phthalate (CAP) by coacervation-phase separation method was studied. Encapsulation was carried out in the CAP-liquid paraffin-acetone ethanol solvent system. The optimum weight ratio for microencapsulation in the CAP-liquid paraffin-solvent system was 1.32:89.18:9.50 or 1.65:89.42:8.93. The wall thickness of microcapsules increased according to increasing of CAP concentration, but dissolution rate decreased. The dissolution of propranolol-HCl in simulated gastric and intestinal fluid test solution was completed within 3 min., but T50% of propranolol HCl from 10.0% CAP-microcapsules were 390 min. and 210 min. respectively. The released amount from 12.5% CAP-microcapsules was 41.8% within 720 min. in simulatd gastric fluid test solution and T50% of those in simulated intestinal fluid test solution was 250 min.

• The Research Journal of the Costume Culture
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• v.9 no.1
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• pp.33-43
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• 2001

In this study, both kinds of materials, that is, leather and woolen fabrics, which have similar thickness, have been adopted. To determine proper length of ease, not only sleeve cap height but also sleeve width has been adjusted mainly based on 5cm length of the ease, which follows maximum sleeve cap height, and then different length of ease, for example, 4cm, 3cm, 2cm and 1cm of ease, have been made. As a result, eighteen kinds in total of sleeves have been made: In other words, each nine kinds of both leather and woolen fabrics have different ease lengths. In addition, each sleeve has been inspected visually and functionally. Following conclusion has been gotten based on outcome of the study: 1. Proper ease length for manufacture of leather garment is said to be 1∼2 cm. As a result, ease length with higher sleeve cap height shall be 1∼2cm, while the length with lower sleeve cap height shall be 1cm or less. 2. Wider sleeve width has better function. Considering relations with sleeve cap height, sleeve width shall exceed +4cm of bicep line. 3. to satisfy a variety of those conditions while manufacturing leather garment, sleeve cap height, which is used for the manufacture of full dress and street wear garment, To lessen the ease length, body A.H shall be relatively loose under the arms, or pad shall be supplemented on the shoulder, so that the difference had better be lessened to solve such problems.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.7
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• pp.481-492
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• 2018

The steel-plate concrete composite beam is composed of a steel plate, concrete and shear connector to combine two inhomogeneous materials. In general, the steel plate is assembled by welding an existing composite beam. In this study, the SPC beam was composed of folding steel plates and concrete, without a headed stud. The folding steel plate was assembled by a high strength bolt instead of welding. To improve the workability in a field construction, a hat-shaped cap was attached to the junction with a slab. Monotonic load testing under two points was conducted under displacement control mode to analyze the flexural strength of the SPC beam using a cap as the shear connector. Five specimens with shear connector types, protrusion length, and different thickness of steel plates were constructed and tested. The experimental results were analyzed through the relationship between the shear strength ratio and flexural strength in KBC 2009. The test results showed a shear strength ratio of more than 40 %. In the case of using a cap-like specimen as the shear connector, the flexural strength was 70% of the value calculated as a fully composite beam. In addition, the cap showed a smaller shear strength than the stud, but the cap served as a shear connection. When the thickness of the steel plate was taken as a variable, the steel plate exhibited a bending strength of approximately 70% compared to a fully formed steel plate, and exhibited similar deformation performance. Local buckling occurred due to incomplete composite behavior, but local buckling occurred at a 5% higher strength for a relatively thick steel plate. The buckling width also decreased by 15%.

• Geomechanics and Engineering
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• v.9 no.2
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• pp.219-241
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• 2015

In this paper, a series of repeated load tests were carried out on a 150 mm diameter plate simulative of vehicle passes, to demonstrate the benefits of soil-rubber shred mixture in decreasing the soil surface settlement of road embankment. The results show that the efficiency of rubber reinforcement is significantly a function of the rubber content, thickness of rubber-soil mixture and soil cap thickness over the mixture. Minimum surface settlement is provided by 2.5% of rubber in rubber-soil mixture, the thickness of mixture layer and soil cap of 0.5 times the loading surface diameter, giving values of 0.32-0.68 times those obtained in the unreinforced system for low and high values of amplitude of repeated load. In this installation, in contrast with unreinforced bed that shows unstable response, the rate of enhancement in settlement decreases significantly as the number of loading cycles increase and system behaves resiliently without undergoing plastic deformation. The findings encourage the use of rubber shreds obtained from non-reusable tires as a viable material in road works.

• Journal of the Korean Society of Radiology
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• v.12 no.7
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• pp.801-806
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• 2018

Germanium crystals have a dead layer that causes efficiency deterioration because the layer is not useful for detection but strongly weakens the photons. Thus, when the data provided by the manufacturer is used in the detector simulation model, there is a slight difference between the calculated efficiency and the measured efficiency.The shape and dimensions of the high purity germanium (HPGe) detector were determined by CT scans to accurately characterize the shape for the Monte Carlo roll simulation. It is found that the adjustment of the dead layer is a good match with the relative deviation of ${\pm}3%$ between the measurement efficiency and the simulation efficiency at the energy range of 50 - 1500 keV. Simulation data were compared by varying the thickness of the dead layer. The new Monte Carlo simulations were compared with the experimental results to obtain new blank layer thicknesses. The difference in dead layer results for the 1.5 mm thick end cap simulation model in 1.4 and 1.6 mm thick End Cap simulation models was a systematic error due to the accuracy of the end cap dimensions. After considering all errors including statistical errors and systematic errors, the thickness of the detector was calculated as $1.02{\pm}0.14mm$. Therefore, it was confirmed that the increase in the thickness of the dead layer causes the effect to be effected on the efficiency reduction.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.153-153
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• 2009

We investigated the dependence of the memory margin of the Cap-less memory cell on the strain of top silicon channel layer and also compared kink effect of strained Cap-less memory cell with the conventional Cap-less memory cell. For comparison of the characteristic of the memory margin of Cap-less memory cell on the strain channel layer, Cap-less transistors were fabricated on fully depleted strained silicon-on-insulator of 0.73-% tensile strain and conventional silicon-on-insulator substrate. The thickness of channel layer was fabricated as 40 nm to obtain optimal memory margin. We obtained the enhancement of 2.12 times in the memory margin of Cap-less memory cell on strained-silicon-on-insulator substrate, compared with a conventional SOI substrate. In particular, much higher D1 current of Cap-less memory cell was observed, resulted from a higher drain conductance of 2.65 times at the kink region, induced by the 1.7 times higher electron mobility in the strain channel than the conventional Cap-less memory cell at the effective field of 0.3MV/cm. Enhancement of memory margin supports the strained Cap-less memory cell can be promising substrate structures to improve the characteristics of Cap-less memory cell.