• Spatial Information Research
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• v.16 no.3
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• pp.279-290
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• 2008

Landslide, one of the serious natural disasters, has Incurred a large loss of human and material resources. Recently, many forecasting or alarm systems based on various kinds of measuring equipment have been developed to reduce the damage of landslide. However, only a few of these equipments are guaranteed to evaluate the safety of whole side of land slope with their accessibility to the slope. In this study, we performed some experiments to evaluate the applicability of a terrestrial LiDAR as a surveying tool to measure the displacement of a land slope surface far a slope collapsing protection system. In the experiments, we had applied a slope stability method to a land slope and then forced to this slope with a load increasing step by step. In each step, we measured the slope surface with both a total station and a terrestrial LiDAR simultaneously. As the result of Slope Fracturing analysis using all targets, the LiDAR system showed that three was 1cm RMSE on X-axis, irregularity errors on Y-axis and few errors on Z-axis compare with Total Station. As the result of Slope Fracturing analysis using continuous targets, the pattern of Slope Fracturing was different according to the location of continuous targets and we could detect a continuous change which couldn't be found using Total station. The accuracy of the LiDAR data was evaluated to be comparable to that of the total station data. We found that a LiDAR system was appropriate to measuring the behaviour of land slope. The LiDAR data can cover the whole surface of the land slope, whereas the total station data are available on a small number of targets. Moreover, we extracted more detail information about the behavior of land slope such as the volume and profile changes using the LiDAR data.

• Elastomers and Composites
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• v.47 no.1
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• pp.43-53
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• 2012

A suspension copolymerization of styrene and butyl methacrylate (BMA) in the aqueous phase was conducted at a selected temperature between 65 and $95^{\circ}C$. Hydrophobic silica was selected as a stabilizer and azobisisobutyronitrile (AIBN) as an initiator. Optimum dispersion of silica in water was obtained at pH 10 while polymerization reaction was run at pH 7. TGA and EDS measurements revealed that 90% of silica functioned as a stabilizer and 10% were incorporated into polymeric particles. Average particle diameter decreased with increasing amounts of stabilizer. Molecular weights displayed an increase when the stabilizer concentration reached 1.67 wt%. An increase in the initiator concentration and/or reaction temperature raised the reaction rate but decreased molecular weights. Particle diameter was nearly independent of the initiator concentration and reaction temperature. An increase in the BMA proportion decreased the glass transition temperature and increased the particle diameter with irregularity in shape. Incorporation of carbon black into the particles composed of styrene and BMA prolonged the reaction time before reaching completion. We have confirmed that a suspension copolymerization of styrene and BMA with hydrophobic silica as a stabilizer can produce spherical composite particles with $1-30{\mu}m$ in diameter containing carbon black.

• Applied Microscopy
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• v.25 no.4
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• pp.26-51
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• 1995

The present study was designed to examine effect of long term weight-training on aging atrophy in the rat skeletal muscle. Male rats of 8, 15, and 24 month old were used. Each age groups included control and weight-training for 5 months by using body press apparatus. The histo- and cytochemical, ultrastructural and stereological changes in aging skeletal muscles of the rat were observed in the present study. During the training period the body weight and muscular weight in all groups except the rectus femoris and the gastrocnemius in young age groups remained constant, but muscular weights were increased in the rectus femoris and the gastrocnemius muscles in young age groups. In trained rat, the volume density of muscle fiber type IIA and IIB were increased, but those of type IIC was decreased. Type I remained constant in 8 and 15 month old age groups, but reduced in the tibialis anterior and the gastrocnemius muscles in the 24 month old groups. Some histotological and ultrastructural changes associated with age were found: numerical increase of cytiplasmic vacuoles, lysosomes, lipofuscins, and irregularity of myofibrils. At 24 month old groups some unusual formation of contraction band and muscle splitting were observed. After weight-training, ultrastructural degenerative changes occured in the type I muscle fiber, such as splitting of muscle fiber, disorganization of myofilaments, swelling of mitochondria, accumulation of many lipid droplets, appearance of many lysosomes and residual bodies and necrotic fibers, in the old age groups. But, in the type II muscle fibers hypertrophy of muscle fiber appeared without any noticible damage as the type I. The activities of $Mg^{++}$ -ATPase decreased with age and this enzyme activities in the trained rat were significantly decreased with age. Activities of the acid phosphatase were increased with age and significantly in the trained rat. In stereological analysis, volume density of the myofibrils and the tubular system were increased, on the other hand there mitochondrial capacity was decreased. These experimental results suggested that old rats are not susceptible to be affected by weight-training as young rats, and that physical capacity of the rats must be considered when old rats are exercised for training.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.23 no.4
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• pp.151-156
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• 1987

The author carried out an experiment to find out the response of sea-bass, Epinephelus septemfasciatus (Thunberg) to the color lights. The experimental tank (360L$\times$50W$\times$55H cm) was set up in a dark room. Six longitudinal sections with 60 cm intervals are marked in the tank to observe the location of the fish. Water depth in the tank was kept 50 cm level. Light bulbs of 20 W at the both ends of the tank projected the light horizontally into the tank. Two different colored filters were selected from four colors of red, blue, yellow, and white, and they were placed in front of the light bulbs to make different colors of light. Light intensity were controlled by use of auxiliary filters intercepted between the bulb and the filter. The fishes were acclimatized in the dark for 50 minutes before they were employed in the experiment. Upon turning on the light, the number of fish in each section was counted 40 times in 30 second intervals, and the mean of the number of fish in each section was given as the gathering rate of the fish. The colors favourited by the fish was found in the order of blue, red, white and yellow in day time, and red, blue, yellow and white at night time. The gathering rate of fish on illumination period was not constant and fluctuated with irregularity. The difference of the gathering rate on two different colors of light was small and the difference was larger in night time then in day time.

• Korean Journal of Community Nutrition
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• v.7 no.6
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• pp.749-761
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• 2002

This study investigated the anthropometric and biochemical indices, and the health and nutritional factors influencing the two indices among 194 middle-aged and elderly subjects (108 middle-aged and 86 elderly) residing in a medium sized city for more than 10 years. In the examination of their dietary habits, 8.3% of the middle-aged subjects and 14.0% of the elderly subjects had two meals a day, and more female subjects had two meals per day. Of the subjects who ate meals at regular times, 75.0% were middle-aged and 79.1% were elderly, and the degree of irregularity of meals was greater for female subjects. The study of the dietary behavior of the subjects indicated that 71.3% and 66.3% of the middle-aged and elderly, respectively responded that the amount of food in each meal was sufficient. The subjects ate alone comprised 19.7% of the middle-aged females and 31.5% of the elderly females. The prevalence of smoking among the subjects was 28.1% for the middle-aged, 18.8% for the elderly male and 7.4% for the elderly females. The percentage of the subjects who drank alcohol was 34.4% of the middle-aged males and 13.2% of the middle-aged females. Slightly less than half of the subjects exercised more than once a week, with the male subjects showing a higher rate than the female subjects. The average body mass indices (BMI) were 24.5 and 24.6 for the middle-aged male and female, respectively, and 22.6 and 24.0 for the elderly male and female, respectively. BMI assessment showed that underweight subjects (BMI ＜ 20) comprised 3.7% of the middle-aged, 14.0% of the elderly, and that 40.7% of the middle-aged and 24.4% of the elderly were overweight (25 ＜ BMI ＜ 30) , and 0.9% of the middle-aged and 1.2% of the elderly were classified as obese (BMI $\geq$ 30) . A waist/hip ratio (WHR) greater than 0.8 was found in 89.5% of the middle-aged females and 90.7% of the elderly females, showing high abdominal fat deposition in the majority of females. The average systolic blood pressure of females was 121.1 $\pm$ 17.1 mmHg for the middle-aged and 129.6 $\pm$ 21.3 mmHg for the elderly subjects. The systolic blood pressures showed a significantly difference between the two age groups. Those defined as anemic subjects based on hemoglobin values comprised 13.0% of the middled-aged group and 16.3% of the elderly group. There was a tendency for higher fasting glucose levels among the elderly subjects. An increase in total plasma cholesterol levels with age was shown. The female subjects had higher cholesterol levels than the males'The study of the correlation between the daily habits and health status showed that the amount of food eaten at each meal, the frequency of eating out, and the use of dietary supplements appeared to influence BMI, WHR, the plasma triglyceride and plasma cholesterol levels; omitting one meal had a positive correlation with the systolic blood pressure and plasma cholesterol. These results suggest that desirable dietary habits and concerns for health are contributing factors for maintaining good health, as indicated by normal blood lipid levels.

• Journal of Advanced Marine Engineering and Technology
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• v.41 no.4
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• pp.302-309
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• 2017

If a hydrogen explosion occurs in a containment building, its multiplex defense wall may be destroyed and a large amount of radioactive material may be released. The hydrogen occurred interacting with melting fuel rods must be effectively controlled and removed. however, the countermeasures for reducing explosion risk are difficult to carry out, due owing to the various variety of accident scenarios causes and the irregularity of hydrogen distribution and behavior. In this study, We examine the guide structures while considering the ambient flows, in order to improve the efficiency of PAR the widely used Passive Autocatalytic Recombiner(PAR). We simulate the fluid behavior and the hydrogen reduction rate were simulated when a guide is attached to the two-step catalyst PAR. For an upward flow, the consisting of a height of 150mm, a gap of 0mm, and a performs $60^{\circ}$ showed the best. In contrast, for a sideways flow, a consisting of the height of 150mm, a gap of 100mm, and a performs $60^{\circ}$ showed the best in the case of side ward flow. for a downward flow, a consisting of the height of 50mm and a directly attached guide produce the best in the case of down ward flow results.

• The Korean Journal of Nuclear Medicine
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• v.19 no.2
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• pp.25-41
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• 1985

간흡충증은 한국 및 동남아세아에 널리 분포되어 있는 중요한 풍토병의 하나로서 진단은 전통적으로 분변검사에 의존하여 오고 있다. 최근 들어 담관내 간흡충 및 이의 합병증의 진단을 위해 ERCP 및 contrast cholangiogram등이 시도되었으나 실제에 이용하기에는 많은 제약이 있다 하겠다. 저자는 간흡충증에 있어서 최근 소개된 $^{99m}Tc-DISIDA$ hepatobiliary scintigraphy의 진단적 의의를 규명하고자 1982년부터 1983년까지 고신의대 부속 복음병원에서 검진한 간흡충증 환자 90명을 대상으로 하여 $^{99m}Tc-DISIDA$ hepatobiliary scintigraphy와 formalin-ether 원침법에 의한 분변검사를 시행하였다. $^{99m}Tc-DISIDA$ scintigram소견은 간내 담관 bile flow 및 총수담관 bile flow defect, 그리고 간세포기능의 정도에 따라 자료를 분석하였고 그외 합병증의 진단은 병록 기록, 수술 소견, ERCP 등에 의존하여 결론을 얻었다. $^{99m}Tc-DISIDA$ scintigraphy는 특이한 양상의 bile flow dynamics를 나타내었으며 간내 주담관의 intermittent irregular focal bile flow defect 및 tile flow stasis를 나타내고 말초담관의 bile flow defect는 경미하고 60분 내에 담관 bile flow activity의 완전한 배설을 나타내는 경우를 mild pattern, 간내 담관의 심한 irregular bile flow dynamics 및 간내담관의 심한 irregularity (담관내벽의 심한 불규칙성), 총수담관, 간내 주담관 및 말초 담관까지 심하게 irregular bile flow stasis를 나타내며 bile flow activity의 완전 베설이 $60\sim90$분사이 혹은 90분이상까지 인지된 경우를 moderate-severe pattern으로 분류하였다. 1) 분변검사상 간흡충증은 95검사중 70검사(환자 86명중 67명)에서 양성을 보여 분변 충난검사의 양성율은 73.7%였고 음성율은 26.3%였다. 2) $^{99m}Tc-DISIDA$ hepatobiliary scintigraphy는 90명중 70명에서 특이한 Cs-bile flow양성을 보였으며 양성율은 77.8%였으며 음성율은 22.2%였다. 3) $^{99m}Tc-DISIDA$ hepatobiliary scintigram양성율을 나타낸 환자 70명중 11명은 mild pattern, 59명은 moderate-severe pattern을 나타냈으며 그중 21명은 여러가지 간세포 기능 및 담관에 영향을 미치는 질환과 합병했지만 특이한 Cs-bile flow pattern을 dominent하게 나타내었으며 합병된 여러 질환들도 bile flow pattern상 인지 할 수 있었다. 4) $^{99m}Tc-DISIDA$ hepatobiliary scintigram 음성율을 나타낸 환자 20명중 8명은 만성간염, 5명은 간경변증, 3명은 재발성 농양성담관염(recurrent pyogenic cholangitis)과 간내담도의 stricture 및 담관담석증이 합병되었으며 scintigram상 합병증의 pattern을 나타냈고 4명에서는 low CBD obstruction을 나타내었으며 후에 CBD stone, CBD carcinoma, gall bladder Ca.의 porta hepatis 전이 및 clonorchis worms의 cluster에 의한 obstruction이 operation 및 ERCP로서 진단 되었다. 5) $^{99m}Tc-DISIDA$ hepatobiliary scintigraphy pattern은 현재의 자각증상과 관계된 dominent disease를 나타내었으며, 공간 점유병소도 multiple project images를 시행하므로서 쉽게 발견할 수 있었다. 이와 같이 간흡충증에 있어서 $^{99m}Tc-DISIDA$ hepatobiliary scintigram은 환자의 자각증상과 관계된 질환을 규명하는 데 필요한 정보를 얻었을 수 있었으며 간내담관의 damage정도를 규명하는데 필요한 procedure임이 판명되었다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.9
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• pp.643-651
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• 2020

A capsule train runs inside a sub-vacuum tube and can reach very high speed due to the low air resistance. A capsule train uses a superconducting electrodynamic suspension (SC-EDS) method for levitation, which allows for a large levitation gap and does not require gap control. However, SC-EDS has inherent characteristics such as the large gap variation and a small damping effect in the levitation force, which can degrade the running stability and ride comfort. To overcome this, a stability improvement device should be designed and applied based on dynamic analysis. In this study, a 1/10 small-scale testbed was developed to replicate the dynamic characteristics of a capsule train and investigate the performance of stability improvement devices. The testbed is composed of a 6-degree-of-freedom Stewart platform for the realization of bogie motion, a secondary suspension with a running stabilization device, and a carbody. Based on the dynamic similarity law proposed by Jaschinski, the small-scale testbed was manufactured, and a bogie motion algorithm was applied with the consideration of guideway irregularity and levitation stiffness. The experimental results from the testbed were compared with simulation results to investigate the performance of the testbed.

• Journal of Conservation Science
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• v.27 no.4
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• pp.381-393
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• 2011

This study focus on the surface deterioration diagnosis based on the material characteristics of Taean Dongmunri Maaesamjonbulipsang(rock-carved standing triad Buddha Statue) and the weathering environment analysis. Rock materials of the triad Buddha is coarse-grained biotite granite which is composed mainly of quartz, K-feldspar, plagioclase, biotite and muscovite. The triad Buddha was serious surface irregularity(13.5%), exfoliation(12.3%) and discoloration(46.6%), and the physical characteristics using ultrasonic velocity appeared fourth grade (0.59, highly weathered). Korean style wooden shelter of the triad Buddha(closed type) maintained high humidity environment (daily mean; 86.6%) than exterior environment, and appeared the possibility of deterioration by freezing-thawing because the temperature showed below zero temperatures in winter. The shelter was changed from closed-type to open-type to relieve the moisture problem recently. But the moisture problem is yet to be solved because surface water flowing along northern wayside is flowed into triad Buddha. Therefore, environmental control will need to stop inflow of water into triad Buddha.

• Journal of Periodontal and Implant Science
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• v.32 no.3
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• pp.523-537
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• 2002

The present study was performed to evaluate the effect of tetracycline - HCl on the change of implant surface microstructure according to application time. Implants with pure titanium machined surface, SLA surface and $TiO_2blasted$ surface were used. Implant surface was rubbed with 5Omg/ml tetracycline - HCl solution for ${\frac}{1}{2}$ min., 1 min., $1{\frac}{1}{2}$ min., 2 min., and 3min. respectively in the test group and with no conditioning in the control group. Then, the specimens were processed for scanning electron microscopic observation. The following results were obtained. 1. In the pure titanium machined surfaces, the control specimen showed a more or less rough machined surface composed of alternating positive and negative lines corresponding to grooves and ridges. After treatment, machining line was more pronounced for the control specimens. but in general, test specimens were similar to control. 2. In the SLA surfaces, the control specimen showed that the macro roughness was achieved by large-grit sandblasting. subsequently, the acid-etching process crated the micro roughness, which thus was superimposed on the macro roughness. 3. In the SLA surfaces, irrespective of the application time of 50mg/ml tetracycline-HCl solution, in general, test specimens were similar to control. 4. In the $TiO_2blasted$ surfaces the control specimen showed the rough surface with small pits. The irregularity of the $TiO_2blasted$ surfaces with 50mg/ml tetracycline-HCl solution was lessened and the flattened areas were wider relative to the application time of tetracycline - HCl solution. In conclusion, pure titanium machined surfaces and SLA surfaces weren't changed irrespective of the application time of tetracycline-HCl solution. And the $TiO_2blasted$ surfaces conditioned with tetracycline - HCl solution began to be changed from $1{\frac}{1}{2}$ min. This results are expected to be applied to the regenerative procedures for peri-implantitis treatment.