• Journal of the Institute of Electronics Engineers of Korea SP
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• v.47 no.1
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• pp.91-96
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• 2010

In this paper, a deformation measurement technology of the nuclear fuel rod is proposed. The deformation measurement system include high definition CCD or CMOS image sensor, lens, semiconductor laser line beam marker, and optical & mechanical accessories. The basic idea of the deformation measurement is to illuminate the outer surface of the fuel rod with collimated laser line beam at an angle of 45 degrees or higher. The relative motion of the fuel rod in the horizontal direction causes the illuminated laser line beam to move vertically along the surface of the fuel rod. The resulting change of laser line beam position in the surface of the fuel rod is imaged as the parabolic beam in the high definition CCD or CMOS image sensor. From the parabolic beam pattern, the ellipse model is extracted. And the slope of the long and the short axis of the ellipse model is found. The crossing point between the saddle point of the parabolic beam and the long & short axis of the ellipse model is taken as the feature of the deformed fuel rod. The vertical offset between feature points before and after fuel rod deformation is calculated. From the experimental results, $50\;{\mu}m$ inspection resolution is acquired using the proposed method, which is three times enhanced than the conventional criterion ($150\;{\mu}m$) of the guide for the inspection of the nuclear fuel rod.

• Elastomers and Composites
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• v.47 no.1
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• pp.36-42
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• 2012

More than 3 wt% of polycyclic aromatics (PCAs) in process oil is known to cause skin cancer. The criterion of distinguishing between low PCA oil and high PCA oil is based on 3 wt% of PCA. High PCA oil is called as a carcinogen like distillate aromatic extract (DAE). Low PCA oil is considered as safety oils like treated distillate aromatic extract (TDAE), mild extract solvate (MES), and paraffinic oil. Four types of process oils such as DAE, TDAE, MES, and paraffinic oil purified by solvent extraction and separation skills from SBR vulcanizates were measured by FT-IR techniques. The effects of rubber chemicals such as N-1,3-dimethylbutyl-N'-phenyl-p-phenylnenediamine (HPPD), polymerized 2,2,4-trimethyl-1,2-dihydroquinoline (TMDQ), paraffin wax as antidegradants, and processing aid like Structol 40MS on paraffinic oil from SBR vulcanizates were also studied. The type of low or high PCA was identified by the relative abundance of absorbance at the aromatic substitution patterns of 864, 810, and $754cm^{-1}$ and at the paraffinic or naphthenic pattern of $721cm^{-1}$.

• Horticultural Science & Technology
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• v.32 no.4
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• pp.473-483
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• 2014

In this work, the effects of shade combination, shade height and wind regime on greenhouse climate were quantified. A two-dimensional (2-D) computational fluid dynamics (CFD) model was developed based on an 11-span plastic greenhouse in eastern China for wind almost normal to the greenhouse orientation. The model was first validated with air temperature profiles measured in a compartmentalized greenhouse cultivated with mature lettuce (Lactuca sativa L., 'Yang Shan'). Next, the model was employed to investigate the effect of shade combinations on greenhouse microclimate patterns. Simulations showed similar airflow patterns in the greenhouse under different shade combinations. The temperature pattern was a consequence of convection and radiation transfer and was not significantly influenced by shade combination. The use of shade screens reduced air velocity by $0.02-0.20m{\cdot}s^{-1}$, lowered air temperature by $0.2-0.8^{\circ}C$ and raised the humidity level by 0.9-2.0% in the greenhouse. Moreover, it improved the interior climate homogeneity. The assessment of shade performance revealed that the external shade had good cooling and homogeneity performance and thus can be recommended. Furthermore, the effects of external shade height and wind regime on greenhouse climate parameters showed that external shade screens are suitable for installation within 1 m above roof level. They also demonstrated that, under external shade conditions, greenhouse temperature was reduced relative to unshaded conditions by $1.3^{\circ}C$ under a wind speed of $0.5m{\cdot}s^{-1}$, whereas it was reduced by merely $0.5^{\circ}C$ under a wind speed of $2.0m{\cdot}s^{-1}$. Therefore, external shading is more useful during periods of low wind speed.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.1 no.2
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• pp.59-72
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• 1996

The stratigraphy of the Gomso-Bay tidal flat consists of basement, preHolocene oxidized unit, and Holocene tidal sequence in ascending order. The oxidized unit is a yellowish brown stiff mud of the last stadial (or subglacial) stage before 12,000 yr B.P. This yellowish brown preHolocene unit does not contain any marine fossils, but contains plant roots, plant fragments, and also vertical and horizontal microfractures indicating soil-formation when exposed. It is regarded as interfluve deposits. The Holocene tidal sequence is composed of lower mud facies (upper-flat muds), upper sand and muddy sand facies (middle to lower-flat sands). This coarsening-upward and retrograding pattern of Holocene tidal deposits reflects a Holocene sea-level rise. The plots of $\^$14/C-age versus depth of dated samples (peats and shells) show that the sea level of 7,000 yr B.P. was located about 6.5 m below the present mean sea level, and the sea levels of 4,000 yr B.P. and 2,000 yr B.P. were also situated about 3 m and 2.5 m below the present mean sea level, respectively.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.4 no.3
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• pp.237-245
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• 1999

Rates of photosynthesis and respiration of Laminaria japonica sporophytes cultivated on the southeastern coast of Korea were monthly measured in situ and under constant temperature and nitrogen concentration in laboratory from February to July 1996 in order to understand the seasonal photosynthetic performance of this alga. P-I (the relationship between photosynthsis and irradiance) parameters measured in situ varied seasonally. Photosynthetic capacity ($P_{max}$) reached its maximum in March (6.64 mg $O_2{\cdot}gdw^{-1}{\cdot}h^{-1}$) and gradually decreased thereafter. Photosynthetic efficiency (${\alpha}$), which ranged from 0.026 to 0.106, generally showed a similar pattern with the $P_{max}$, curve. Correlation between respiration and $P_{max}$, was not significant (Spearman's rank correlation, p>0.05); respiration rate, which varied between 0.25 and 0.83 mg $O_2{\cdot}gdw^{-1}{\cdot}h^{-1}$, showed no gradual decline from March. $P_{max}$ in situ significantly correlated with the relative growth rate of frond weight (Spearman's rank correlation, p<0.01) and this result means that the amount of accumulated materials in body increased with the increment of $P_{max}$. Compared $P_{max}$, in situ with that in the laboratory. The lower $P_{max}$ in February was probably caused by the effect of lower seawater temperature at this time. The decrease in $P_{max}$ after March, however, was primarily attributable to the thickness of blade as the plants got old. Comparison of P-I parameters measured for different size groups in April, explained the negative relationship between $P_{max}$ and frond thickness.

• Journal of environmental and Sanitary engineering
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• v.7 no.2
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• pp.95-110
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• 1992

Much progress has been made in understanding the subcellular events of the human lung injuries after acute exposure to environmental air pollutants. Host of those events represent oxidative damages mediated by reactive oxygen species such as superoxide, hydrogen peroxide, and the hydroxy, free radical. Recently, nitric oxide (NO) was found to be endogenously produced by endothelial cells and cells of the reticulo-endothelial system as endothelialderived relaxation factor (EDRF) which is a vasoactive and neurotransmitter substance. Together with superoxide, NO can form another strong oxidant, peroxonitrite. The relative importance of exogenous sources of $N0/N0_2$ and endogenous production of NO by the EDRF producing enzymes in the oxidative stresses to the heman lung has to be elucidated. The exact events leading to chronic irreversible damage are still yet to be known. From chronic exposure to oxidant gases, progressive epithelial and interstitial damages develop. Type I epithelial cells become thicker and cover a smaller average alveolar surface area while thee II cells proliferate instead. Under acute damages, the extent of loss of the alveolar epithelial cell lining, especially type II cells appears to be a good predictor of the ensuing irreversible damage to alveolar compartment. Interstitial matrix undergo remodeling during chronic exposure with increased collagen fibers and interstitial fibroblasts. However, Inany of these changes can be reversed after cessation of exposure. Among chronic lung injuries, genetic damages and repair responses received particular attention in view of the known increased lung cancer risks from exposure to several air pollutants. Heavy metals from foundry emission, automobile traffics, and total suspended particulate, especially polycystic aromatic hydrocarbons have been positively linked with the development of lung cancer. Asbestos in another air pollutant with known risk of lung cancer and mesothelioma, but asbestos fibers are nonauthentic in most bioassays. Studies using the electron spin resonance spin trapping method show that the presence of iron in asbestos accelerates the production of the hydroxy, radical in vitro. Interactions of these reactive oxygen species with particular cellular components and disruption of cell defense mechanisms still await further studies to elucidate the carcinogenic potential of asbestos fibers of different size and chemical composition. The distribution of inhaled pollutants and the magnitude of their eventual effects on the respiratory tract are determined by pollutant-independent physical factors such as anatomy of the respiratory tract and level and pattern of breathing, as well as by pollutant-specific phyco-chemical factors such as the reactivity, solubility, and diffusivity of the foreign gas in mucus, blood and tissue. Many of these individual factors determining dose can be quantified in vitro. However, mathematical models based on these factors should be validated for its integrity by using data from intact human lungs.

• Journal of Sericultural and Entomological Science
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• v.46 no.1
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• pp.23-27
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• 2004

We were investigated the cognitive ability enhancement in rats using B. mori fibroin molecular controlled hydrolysate by preparative recycle HPLC system. Also, some of its physicochemical properties and free amino acid components were investigated, too. Nuclear magnetic resonance (NMR) spectrum are measured different pattern between high (HF) and low (LF) molecular controlled B. mori fibroin samples, respectively. The in vitro test by neuron primary cell culture are showed dependent on molecular weight (Mw) of B. mori fibroin in the order of LF > MF > HF, too. However, the memorial effects in rats by in vivo test are large dependent molecular weight on that maximum 50% than control. Also, the memorial effect was higher than the enzymatic relative and acid hydrolysate, which was 50.0$\pm$2.1 and 25.9$\pm$0.32%, respectively.

• Journal of Sericultural and Entomological Science
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• v.30 no.1
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• pp.25-32
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• 1988

In order to examine a physiological role of juvenile(JH) binding proteins in the hemolymph of the silkworm larva, Bombyx mori, [3H] JH I incubated hemolymph was separated by polyacrylamide gel electrophoresis in the fifth-instar larva and the activity of the binding protein was analyzed using charcoal binding assay. The results obtained were as follows; 1. The JH was bound by two protein fractions in the hemolymph of the fifth-instar larva; One was JH binding lipoprotein(JH-LP), the other was JH speific binding protein(JHBP). Their relative mobility values(Rm) were 0.3∼0.33 and 0.81∼0.84, respectively. There were no valid differences in those values from developmental stages of both male and female silkworms. 2. Total protein contents of the hemolymph were gradually increased during the fifth-instar larva, while at the prepupa decreased. The maximum ones were observed at the spinning period and the contents from female were much higher than those from the male. 3. JH binding activity per ml of the hemolymph was low in the early stage of the fifth-instar larva and its activity was maximized at the psinning period and at the prepupa slightly decreased. 4. There was a similar pattern between changes of the JH binding activity per ml of the hemolymph and of the total protein contents of the hemolymph. 5. The JH binding activity per mg of the hemolymph proteins was high in the early stage of the fifth-instar larva, while from the 6th day of the fifth-instar larva to the prepupa its activity showed the lowest levels.

• Korean Journal of Social Welfare
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• v.57 no.3
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• pp.195-222
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• 2005

This study was a comparative analysis by youth's internet addiction types. Distribution of internet addiction types, relative influence of risk and protective factors in each addiction type, and common and different risk and protective factors among the internet addiction types were investigated. And, the level of youth's mental health and the effect of internet to youth's mental health were identified. A total of 1,830 youth were surveyed, and the findings were as below: Firstly, 62.3% of the surveyed youth were addicted to internet. In detail, 15.9% had internet game addiction and 10.9% had internet sex addiction. Secondly, in all types of internet addiction, the risk factors gave severer influence than the protective factors did, and the protective factors gave compensation effect to each type of addiction. Thirdly, among the internet addiction types, the common risk factors were depression, aggression, parents' control, and friends' influence, while the protective factor was self control. Among the internet addiction types, a different risk factor was PC access, and the different protective factors included self-efficacy, teacher's support, friend's support, and parents' relationship. Fourthly, in all the three addiction pattern, the addicted adolescents had experienced more psychological symptoms than general internet users had. Finally, in the aspects of psychiatric symptoms, sex addiction gave the worst negative effect, and then game addiction, and internet addiction came in order. And the adolescents who had the higher degree of addiction were more likely to experience psychiatric symptoms.

• The Journal of the Korean bone and joint tumor society
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• v.3 no.1
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• pp.18-25
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• 1997

Prosthetic replacement is one of the most common methods of reconstruction after resection of malignant tumor around the knee. Gait analysis provides a relative objective data about the gait function of patients with prosthesis. The purpose of this study was to compare the gait pattern of the patients who underwent limb salvage surgery with prosthesis for distal femur and that of patients with prosthesis for proximal tibia. This study included ten patients (4 males, 6 females, mean age 22.7 years, range 14-36) who underwent a wide resection and Kotz hinged modular reconstruction prosthesis replacement and six normal adult(Control). The site of bone tumor was the distal femur (Group 1) in six patients and proximal tibia (Group 2) in 4 patients. The follow-up period ranged from 15 to 82 months (mean : 33 months). The evaluation consisted of clinical assessment, radiographic assessment, gait analysis using VICON 370 Motion Analysis System. The gait analysis included the linear parameters such as, walking velocity, cadence, step length, stride length, stance time, swing time, single support and double support time and the three-dimensional kinematics (joint rotation angle, velocity of joint rotation) of ankle, knee, hip and pelvis in sagittal, coronal and transverse plane. For the kinetic evaluation, the moment of force (unit: Nm/kg) and power (unit: Watt/kg) of ankle, knee and hip joint in sagittal, coronal and transverse plane. In the linear parameters, cadence, velocity, step time and single support were decreased in both group 1 and group 2 compared with control. Double support decreased in group 2 compared with control significantly(p<.05). In contrast to our hypothesis, there was no significant difference between group 1 and group 2. In Kinematics, we observed significant difference (p<.05) of decreased knee flexion in loading response (G2