• Steel and Composite Structures
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• v.17 no.5
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• pp.601-621
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• 2014

Repairing and strengthening structural members by bonding composite materials have received a considerable attention in recent years. The major problem when using bonded FRP or steel plates to strengthen existing structures is the high interfacial stresses that may be built up near the plate ends which lead to premature failure of the structure. As a result, many researchers have developed several analytical methods to predict the interface performance of bonded repairs under various types of loading. In this paper, a numerical solution using finite - difference method (FDM) is used to calculate the interfacial stress distribution in beams strengthened with FRP plate having a tapered ends under thermal loading. Different thinning profiles are investigated since the later can significantly reduce the stress concentration. In the present theoretical analysis, the adherend shear deformations are taken into account by assuming a parabolic shear stress through the thickness of both beam and bonded plate. The shear correction factor for I-section beams is also included in the solution. Numerical results from the present analysis are presented to demonstrate the advantages of use the tapers in design of strengthened beams.

• Korean Journal of Environmental Agriculture
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• v.29 no.2
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• pp.102-108
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• 2010

The effects of foliar spray of calcium hydroxide ($Ca(OH)_2$) during fruit growth period was investigated by changes of the shoot growth and fruit quality in 'Daewol' peach (Prunus persica). Since foliar spray of $Ca(OH)_2$ 1, 2, 5, and 10 $g{\cdot}L^{-1}$ at 7 day-intervals after fruit thinning, shoot growth was remarkably decreased compared with control group. An average SPAD value of fifth leaf from proximal part of the shoot was higher as 42.1 specific color difference sensor value (SCDSV) of $Ca(OH)_2$ foliar spraying treatments than 40.9 SCDSV of control group. Photosynthesis rates were also significantly increased by treating $Ca(OH)_2$ of higher concentration. Among fruit characteristics affecting quality, fruit weight was increased depending on concentration of $Ca(OH)_2$ treatment. The soluble solids content was lowest in control group (8.78 $^{\circ}Brix$) compare with higher concentrations of $Ca(OH)_2$ foliar spraying treatment in each 9.17, 9.22, 9.71, 10.58 $^{\circ}Brix$. The acidity and anthocyanin contents were no significant differences among treatment, but firmness of pericarp and flesh of fruits was significantly increased by $Ca(OH)_2$ foliar spray treatment. As a results of morphological observation of leaf, thickness of palisade parenchyma was thinner in control group (63.5 ${\mu}m$) than those of each 86.5, 87.5, 93.6, 107.4 ${\mu}m$ in $Ca(OH)_2$ foliar spraying treatment. Higher $Ca(OH)_2$ foliar spray also increased the thickness of cell wall of epidermis and hypodermis in 'Daewol' fruit.

• Proceedings of the Korean Society of Rheology Conference
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• 2006.06a
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• pp.81-84
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• 2006

Slot coating process, in continuous and patch modes, has been applied for the many precise coating products, e.g., flat panel displays and second batteries. However, manufacturing uniform coating products is not a trivial task at high-speed operations because various flow instabilities or defects such as leaking, bubbles, ribbing, and rivulets are frequently observed in this process. It is no wonder, therefore, that many efforts to understand the various aspects of dynamics and coating windows of this process have been made both in academia and industry. In this study, as the first topic, flow dynamics within the coating bead in slot coating process has been investigated using the one-dimensional viscocapillary model by lubrication approximation and two-dimensional model by Flow-3D software. Especially, operability windows in both 1D and 2D cases with various slot die lip designs have been successfully portrayed. Also, effects of process conditions like viscosity and coating gap size on slot coating window have been analyzed. Also, some experiments to find minimum coating thickness and coating windows have been conducted using slot die coater implemented with flow visualization device, corroborating the numerical results. As the second topic, flow dynamics of both Newtonian and Non-Newtonian fluids in patch or pattern slot coating process, which is employed in manufacturing IT products such as secondary batteries, has been investigated for the purpose of optimal process designs. As a matter of fact, the flow control in this system is more difficult than in continuous case because od its transient or time-dependent nature. The internal die and die lip designs for patterned uniform coating products have been obtained by controlling flow behaviors of coating liquids issuing from slot. Numerical simulations have been performed using Fluent and Flow-3D packages. Flow behavior and pressure distribution inside the slot die has been compared with various die internal shapes and geometries. In the coating bead region, efforts to reduce irregular coating defects in head and tail parts of one patterned coating unit have been tried by changing die lip shapes. It has been concluded that optimal die internal design gas been developed, guaranteeing uniform velocity distribution of both Newtonian and shear thinning fluids at the die exit. And also optimal die lip design has been established, providing the longer uniform coating layer thickness within one coating unit.

• Childhood Kidney Diseases
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• v.6 no.1
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• pp.48-55
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• 2002

Purpose: Thin glomerular basement membrane nephropathy (TGBMN) is recognized as the leading cause of microscopic hematuria in both children and adults. However thinning of glomerular basement membrane (TCBM) has been found in healthy adult and also is known to be associated with various renal diseases such as Alport syndronh, IgA nephropathy and mesangial proliferative glomerulonephritis. The association of TGBM with minimal change nephrotic syndrome (MCNS) has been very rare so that the present study was undertaken to determine the relationship between TGBM and MCNS. Methods: The study population consisted of 49 children with biopsy- proven MCNS who have been admitted to the pediatric department of Kyungpook University Hospital during the past 5 years from 1997 to 2001. Group I consisted of 8 children associated with TGBM and Group II 41 children without TCBM. Various parameters such as age of illness, duration from discovery of illness to the time of biopsy, family history of hematuria and other laboratory tests were compared between these two groups and the following results were obtained. Results: Age distribution showed slightly older age in Group I ($7.1{\pm}3.5$ years) compared to Group II ($4.8{\pm}2.9$ years). However this was not statistically different (P=0.056). Family history of hematuria was noted in 2 cases in Group II. Though statistically not significant, hematuria was seen in 2 out of 8 cases ($25\%$) in MCNS children with TGBM, compared to 7 out of 41 cases ($17\%$) with MCNS children without TGBM. Other parameters such as BUN, creatinine, 24 hours urine protein excretion, serum protein, albumin, cholesterol, and T4/T8 ratio, showed no difference. Also renal biopsy finding showed no significant difference and the thickness of glomerular basement membrane in Croup I was $188{\pm}30nm$. Conclusion: TGBM was found in 8 out of 49 children with MCNS ($16.3\%$). And this high frequency of occurrence indicates that these association is not an incidental findings. Typical clinical findings of TCBMN was not noted in all of the 8 children with MCNS associated with TGBM, suggesting that thinning of glomerular basement membrane (TCBN) is secondary to rather than the cause of MCNS. (J Korean Soc Pediatr Nephrol 2002;6: 48-55)

• Journal of Animal Science and Technology
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• v.48 no.2
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• pp.219-226
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• 2006

The wastes (the needle leaves and branches) produced from thinning the forest were fermented under an anaerobic condition (pine silage) to utilize as a forage source of ruminants. An in situ trial was conducted with two ruminally fistulated Korean native cows by 4 replicates (2 bags per cow), and in vivo digestibility of pine silage was estimated with five Korean native steers by 5 replicates in incomplete double turn-over design. In order to investigate feed efficiency and carcass traits, forty eight Korean native bulls were assigned to four treatments (0%, 25%, 50%, 75% of pine silage) with a completely randomized design in 12 pens accommodating 4 animals per pen. The amounts of concentrate and roughage allowed to experimental animals were in the range of 2.5% and 0.6% of body weight, respectively. Animals had freely accessed to mineral block and water in stanchion barn.An in situ crude protein digestibility of the roughage sources when suspended for 48 hrs in the rumen was higher for feeding the pine silage than the rice straw, whereas NDF digestibility was vice versa. No differences between the treatments were observed in in vivo digestibilities of dry matter, crude protein and NDF. Daily body weight gain was significantly (P<0.01) higher for the pine silage substitutions compared with the rice straw feeding except for the 25% silage feeding. The pine silage feeding did not affect feed efficiency.In carcass traits, marbling score tended to be higher for the 50% pine silage treatment than the other treatments while back fat thickness tended to be the thinnest for the rice straw feeding. From these results, it may be recommended to substitute pine silage, as a forage source, for rice straw by 50 percent.

• Horticultural Science & Technology
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• v.32 no.1
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• pp.41-45
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• 2014

This study was conducted to investigate the effects of crown numbers on growth and yield of ever-bearing strawberry (Fragaria ${\times}$ ananassa Duch.) 'Goha' cultivar. Strawberry seedlings were planted with $55{\times}30cm$ distance on April 29, and the randomized block experimental was designed by putting the crown numbers by 1, 3, 5 and crown-unremoved as the control. At the early growth stage, as the numbers of crown decreased, the size of leaf became larger and inflorescence diameter became thicker. Plant height became higher as the number of crown increased at the final harvesting time. Fresh weight of crown-unremoved plants was 118 g, showing 77.2 g higher than that of plants with one crown. Numbers of the developed inflorescence of plants with five crowns and crown-unremoved was 20.1, whereas 6.8 of plants with one crown, resulted in 13.3 more crowns. However, crown number did not significantly affect the fruit quality. As the crown number increased, the average fruit weight was lighter and the marketable fruit rate was shown to decrease significantly. The marketable yield of crown-unremoved plants was $17,372kg{\cdot}ha^{-1}$, showing 68% higher than plants with one crown. Therefore, crown management without thinning crowns was recommended and inflorescence thickness less than 3 mm should be removed for successful production of ever-bearing strawberry 'Goha' cultivar during summer season.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.46 no.6
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• pp.35-43
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• 2009

In the Computer Aided Diagnosis(CAD) System, the efficient way of classifying nodules from chest CT images of a patient is to perform the classification of the remaining part after the pulmonary vessel extraction. During the pulmonary vessel extraction, due to the small difference between the vessel and nodule features in imaging studies such as CT scans after having an injection of contrast, nodule maybe extracted along with the pulmonary vessel. Therefore, the pulmonary vessel extraction method plays an important role in the nodule classification process. In this paper, we propose a nodule reclassification method based on vessel thickness analysis. The proposed method consist of four steps, lung region searching step, vessel extraction and thinning step, vessel topology formation and correction step and the reclassification of nodule in the vessel candidate step. The radiologists helped us to compare the accuracy of the CAD system using the proposed method and the accuracy of general one. Experimental results show that the proposed method can extract pulmonary vessels and reclassify false-positive nodules accurately.

• The korean journal of orthodontics
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• v.30 no.2 s.79
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• pp.185-196
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• 2000

Patients who want to reduce their lip protrusion usually estimate the severity of the lip protrusion on the frontal aspect. Most orthodontists have a perplexed experience of a reduced thin line of vermilion border on the frontal aspect as incisors we retracted, even though the lip protrusion is thought to be reduced favorably on the sagittal aspect. Some patients also look older after orthodontic treatment because of severe lip thinning. This unaesthetic reduction of vermilion border urges us to study the vertical lip change during orthodontic procedure. The purpose of this study was to evaluate the vertical lip and perioral soft tissue changes in respect to incisor retraction in an effort to analyze which factors might be responsible for their vertical changes, using the multiple regression analysis. The results were as follows. 1. Upper and lower lip philtrum length(SnLs, LiB') were increased after retraction of anterior teeth, where as upper and lower vermilion height(LsSuls, StmiLi), and vermilion length(LsLi) were decreased. 2. Upper and lower lip length(SnStms, StmiB'), and soft tissue lower anterior facial height(SnMe') did not show any significant difference after treatment. 3. The increase of the upper lip philtrum length was mainly influenced by the extrusion of upper anterior teeth(${\Delta}U1V$), and the increase of the lower lip philtrum length was mainly influenced by the initial overjet before treatment. 4. The decrease of the upper and lower lip vermilion height was mainly influenced by the decrease of upper lip thickness.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.9
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• pp.1469-1475
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• 2004

Skin is the most frequently exposed tissues to oxidative stress from exogenous and endogenous sources. Dietary antioxidants, which suppress oxidative stress including reactive oxygen metabolites, play an important role in protecting skin from deleterious reactive oxygen species. Kimchi containing lots of antioxidative compounds shows anti-aging effect on skin. Therefore the morphologic changes on the skin of hairless mice fed diets containing Korean cabbage, mustard leaf, and buchu kimchi for 16 weeks were determined. Although epidermal thickness was decreased with age, kimchi prevented this thinning of epidermis compared to control group. In kimchi groups, the staining area of cytokeratin was smaller and stratum corneum was thinner than control group. It suggests that various kinds of kimchi diets prevent the increase of keratinization in epidermis with aging. Type Ⅳ collagen, a major structural protein of basement membrane supporting matrices, existed greater amount in kimchi groups than control group, especially in mustard leaf kimchi group. Rough endoplasmic reticulum (RER) of fibroblast was well developed in dermis of Korean cabbage and mustard leaf kimchi groups, which means collagen synthesis at dermis increased in those kimchi groups. This morphological changes of skin suggest that kimchi consumption can retard skin aging due to the presence of antioxidant and anti-aging compounds, especially some components of mustard leaf kimchi may largely affect on the skin rejuvenescence.

• Journal of the Korean Society for Nondestructive Testing
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• v.34 no.5
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• pp.349-355
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• 2014

Wall thinning defects can occur in the pressure vessels used in a variety of industries. Such defects are related to the flow velocity. Considering the fact that such vessels constitute up to 70 or 80% of the plant structures in a power plant, it is important to measure internal defects as part of a safety evaluation. In this study, optical measurement were applied in a non-destructive evaluation using shearography to ensure the safety and improve the reliability of a power plant through the non-contact, non-destructive evaluation of pressure vessels. In order to verify whether the pressure vessels contained faults, experimental and analytical investigation were conducted to measure any internal defects and out-of-plane deformation from inner temperature changes and pressure changes in the piping of the circulation system. The most important factors in this research were the thickness, width, and length of a defect. An increase in these could confirm an increase in the deformation. Thus, internal defects in a pressure vessel were measured using shearography, which made it possible to ensure the reliability and integrity of the pipe.