• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.13 no.3
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• pp.211-218
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• 2015

The reaction rates of ZIRLO cladding hulls with cross-section openings were investigated using a thermo-gravimetric analysis system in order to identify whether selective recovery of Zr from oxidized cladding hulls is possible. The experimental results showed that an oxidized ZIRLO cladding hull was not reactive with chlorine gas at 400℃. However, providing fresh cross-sections on one or both ends of the ZIRLO hulls enabled a chlorination reaction. This reaction was completed after 8 hours; a 14% increase on the 7 hours seen with a bare ZIRLO cladding hull. The Sharp-Hancock plot analysis results revealed that the contracting volume model is the best for describing the reaction between the cross-section opened ZIRLO hulls and chlorine gas under the condition of this work. It was concluded that the chlorination process can be employed for oxidized ZIRLO cladding hulls by providing cross-section openings.

• Journal of the Korean Institute of Landscape Architecture
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• v.43 no.5
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• pp.55-64
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• 2015

In this study, negative air ions, which can increase comfort and positively influence human health, was set as an evaluative factor for school forests. The characteristics, location and microclimate of school forests were examined to determine an effective school forest model for maximum negative air ion generation. It also aimed to provide basic data for the development of urban green fields. The negative air ion concentrations were different according to the green types. The order from the highest to the lowest was: single-layer structure($934ea/cm^3$) > multi-layer structure($794ea/cm^3$) > grass($553ea/cm^3$) > bare ground($529ea/cm^3$). As for the correlation with microclimate, negative air ion concentration was negatively correlated with temperature. The negative air ion concentration was significantly different according to planting type. The negative air ion concentration was higher at single-layer structure sites than at multi-layer structure sites, which appears to indicate that the temperature is higher when the vegetation structure was single-layer compared to multi-layer. Wind speed was higher at the single-layer planted site than at the multi-layer planted site. The vegetation wind shielding effect was lower at single-layer planted sites than at multi-layer planted sites. The single-layer planted site provided more favorable conditions for the generation and dispersion of negative air ions.

• Korean Journal of Applied Biomechanics
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• v.18 no.1
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• pp.245-253
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• 2008

The purpose of this study was to analyze the effects of shoes with curved out-sole on the posture variation and its control strategy. At first, Target shoes(s) was made by evaluating the static postures of 7-female university students via 'New York State Posture Test' on shoes which made the relative angle between foot surface and ground surface of shoe change. At second, we evaluated muscle activity for 30-female university students(10 persons-3 groups) on shoes which were s(target), m shoes with curved out-sole and n shoes with flat out-sole. 1. The posture scores on New York State Posture Test were statistically different according to the relative angle changes, and the best angle for score was -7 degree but, the scores charts were like two humped camel at -2, -7degree. we made the shoe with -7 degree and curved out-sole. 2. s, m shoes with curved out-sole had graded muscle activities but, static posture on bare foot, there were the graded activity on gastrocnemius for s shoes and tibialis anterior for m shoes, but on shoes, only Gastrocnemius for s shoes.

• Proceedings of the Materials Research Society of Korea Conference
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• 2009.11a
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• pp.41.1-41.1
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• 2009

Aerosol Deposition (AD) is anovel way to fabricate bioactive ceramic coatings in biomedical implants and prostheses applications. In the present work, silicon-substituted hydroxyapatite (HA) coatings on commercially pure titanium were prepared by aerosol deposition using Si-HA powders. The incorporation of silicon in the HA lattice is known to improve the bioactivity of the HA, makingsilicon-substitute HA an attractive alternative to pure HA in biomedical applications. Si-HA powders with the chemical formula $Ca_{10}(PO_4)_6-x(SiO_4)x(OH)_2-x$, having silicon contents up to x=0.5 (1.4 wt%), were synthesized by solid-state reaction of $Ca_2P_2O_7$, $CaCO_3$, and $SiO_2$. The Si-HA powders were characterized by X-ray diffraction (XRD), X-ray fluorescence spectrometry (XRF), and Fourier transform infrared spectroscopy(FT-IR). The corresponding coatings were also analyzed by XRD, scanning electron microscopy (SEM), and electron probe microanalyzer (EPMA). The results revealed that a single-phase Si-HA was obtained without any secondary phases such as $\alpha$- or $\beta$-tricalcium phosphate (TCP) for both the powders and the coatings.The Si-HA coating was about $5\;{\mu}m$ thick, had a densemicrostructure with no cracks or pores. In addition, the proliferation and alkaline phosphatase (ALP) activity of MC3T3-E1 preosteoblast cells grown on the Si-HA coatings were significantly higher than those on the bare Ti and pure HA coating. These results revealed the stimulatory effects induced by siliconsubstitution on the cellular response to the HA coating.

• Journal of Science of Art and Design
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• v.6
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• pp.81-99
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• 2004

For making something to use as a tool since the emergence of mankind, the initial pragmatic purpose has transformed into a new genre of art over time. Things defined like this have rooted in our culture as tradition so far. In the midst of today's various trends, a reflection of tradition and a modern search for tradition by re-creating it are much more needed. To any people in any time, a new trend would undeniably develop on the basis of its previous tradition in any form. The colors appearing in such artwork are also an expression of each people's unconscious potentiality as essential grounds for human aesthetic. The traditional Korean Bojaki, which was made out of women's pragmatic mind trying to recycle trashy pieces of cloth in the 19th century of Chosun Dynasty, appears as a symbolization of our nation's original form in unconsciousness. It includes Confucianism, Buddhism, Zen and the Yin-Yang and Five Elements thought, which have been together with naturalism. The five colors appearing in the Yin-Yang and Five Elements are the basis. Fourteen selected samples around the five colors seen in the color scheme of the Chosun era's Bojaki were measured and their color values were found by analyzing them based on HCV(Hue, Chroma, Value)of the five primary colors as well as the five secondary colors. After choosing a few colors with bare eyes close to traditional Primary Colors and Secondary Colors amongst 14 pieces of data which particularly used traditional Five Colors and examining them using spectrophotometer(JX777), the following conclusions were drawn. Comparing only colors in Primary Colors, the result was red 7.11R 4.59/10.69, blue 6.71PB 3.18/6.45, yellow 3.91Y 7.56/6.12, respectively. With regard to Secondary Colors, it was reported that red 7.96RP 5.42/10.3, blue 7.8B 5.16/5.53, green 8.03GY 6.05/4.34, yellow 2.73Y 7.47/4.07, purple 2.39RP 4.69/4.56, respectively. (diagram) As a result, the standard of Five Colors can be used in modern fiber color. There are differences in dyeing material, methods and kinds of fiber of that time, but women of Chosun Dynasty combined and made fabric which was circulated. Consequently, an applicable attribute of the aye-color values was considered.

• Journal of Ocean Engineering and Technology
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• v.25 no.2
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• pp.85-91
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• 2011

Many protection methods such as surface coating, electric protection, or other methods have been applied to the numerous steel structures widely used in continental and marine areas to control their corrosion, which is done from an economic point of view. Most of these steel structures are primarily protected by coating methods. However, some steel piles under seawater are protected by the electric protection method, that is, either using an impressed current or a sacrificial anode method. Furthermore, environmental contamination may cause a severely corrosive environment, which, in turn, causes the accelerated corrosion of steel structures. Subsequently, coated steel structures could deteriorate more rapidly than the designed lifetime because of the acid rain caused by air pollution, etc. Therefore, a coating of marine paint exposed to seawater, that is, underwater hardening painting, is increasingly required to be fast drying as well as highly corrosion resistant. In this study, five types of underwater hardening paints were prepared with different resin series and additives. Their corrosion and water resistances were investigated using electrochemical methods such as corrosion potential, polarization curves, impedance and cyclic voltammogram measurements, etc. Even though it is generally accepted that the corrosion resistance of bare steel tends to increase with a shift of the corrosion potential in the noble direction, the corrosion resistance of a sample with a coating exhibited a relatively better tendency when it had a lower corrosion potential in this study. The corrosion current density was also decreased with a decrease in the diffusion limiting current density, which may mean that there is some relationship between corrosion and water resistance. The S sample of the ceramic resin series showed the relatively best corrosion and water resistance among those of samples, while the worst corrosion and water resistance were observed for the R sample of the epoxy resin series. The corrosion and water resistance of those samples tended to deteriorate with an increase in the immersion days, and their corrosion and water resistances were considered to be apparently improved by the types of resin and additives.

• Journal of Radiation Protection and Research
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• v.21 no.2
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• pp.125-129
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• 1996

The energy response of HPGe detector for low energy Photons was determined by using three Monte Carlo codes. MCNP4A. EGS4, and CYLTRAN in ITS3. In this study. bare HPGe detector$(100 mm^2{\times}10mm)$ was used and a pencil beam was incident perpendicularly on the center of the detector surface. The photopeak efficiency, $K_{\alpha}$ and $K_{\beta}$ escape fractions were calculated as a function of incident X-ray energies ranging from 12 to 60 keV in 2-keV increments. Since the Compton. elastic. ana penetration fraction were negligible in this energy range. they were ignored in the calculation. Although MCNP. EGS, and CYLTRAN codes calculated slightly different energy response of HPGe detector for low energy Photons, it appears that the three Monte Carlo codes can Predict the low energy Photon scattering Processes accurately. The MCNP results, which are generally known as to be less accurate at low energy ranges than the EGS and ITS results. are comparable to the results of EGS and ITS and are applicable to the calculation of the low energy response data of a detector.

• Journal of Korean Society of Forest Science
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• v.81 no.3
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• pp.287-298
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• 1992

The main purpose of this study is to obtain information on the factors influencing forest scenic beauty in order to make and manage scenic forest of recreation areas. 62 slides were taken for the study. Each photograph was independently judged by college students in 10 different major fields, with a total 264 observers after reliability test in the study. The ratings were scaled using a computer program developed by Brown & Daniel(1990). The results of rating scale analysis indicate that respondents' major field difference affects visual preference for forest scenic beauty. Similarly, with different sexual, forest visit frequency, and community type in childhood, people tend to rate their preference differently. The respondents' rating scale of relative scenic beauty of near-view forest scenes can largely be explained in terms of forest physical characteristics of forest landscape. Bare ground area and stash area are represented negative esthetic effects, while DBH, number of trees per hectare, sky area showed positive esthetic effects. These 6 variables in the model can be accounted for 74% of total variance in perceived forest scenic beauty. With this study result, it can be concluded that forest physical characteristics are significantly related to visual preference for near-view forest scenes.

• Annals of Clinical Neurophysiology
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• v.4 no.2
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• pp.119-124
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• 2002

Background : Guillain-$Barr{\acute{e}}$ syndrome(GBS) is a neurologically emergent condition, leading to respiratory insufficiency without an early and appropriate treatment. Thus, the treatment of GBS requires early diagnosis but it is difficult due to the low sensitivity of laboratory tools in the initial stage. Hoffman reflex (H-reflex) and its facilitation by Jendrassik maneuver (JM) are sensitive tools evaluating the central circuit of motor system on the spinal cord level. The aim of this study is to test whether the change of H-reflex and F-wave under the JM is able to detect the early stage of GBS and whether GBS involves the central nervous system (CNS). Material and Methods : All 7 GBS patients who showed normal or nearly normal nerve conduction study were included. The facilitation of H-reflex and changes of F-wave were calculated by measuring the percent difference of H-reflex or F-wave amplitude under JM compared to basal H-reflex of F-wave amplitude. The changes of F-wave and H-reflex in the GBS patients were compared with them of 8 healthy controls. Results : The F-wave amplitudes of both healthy controls and GBS patients did not changed under the influence of JM ($102.4{\pm}24.9%$, $108.7{\pm}29.0%$ respectively). However, the facilitation of H-wave by JM in the GBS patients was absent ($98.8{\pm}5.8%$), even though the H-reflex amplitude I the healthy controls increased under the influence of JM ($124.8{\pm}12.1%$). Conclusions : The loss of H-reflex facilitation in GBS implies that this phenomenon might be the most early change detected in the electrophysiological study and support the early diagnosis, and that GBS might include lesion in the spinal motor CNS.

• Korean Journal of Environmental Agriculture
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• v.32 no.1
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• pp.35-41
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• 2013

BACKGROUND: In organic agriculture, various cover crops have been used to control weeds. In this study, we investigated the suppressive effects of Vicia tetrasperma (L.) Schred (Eolchigi wandu) on the occurrence of major insect pests and their natural enemies in pepper. METHODS AND RESULTS: To estimate the effect of cover-crop on arthropod diversities and occurrences of insect pest in pepper. V. tetrasperma was sowed as cover-crop plot October, 2008 and 2009. Control plot was kept bare in winter season and mulched with black plastic-film before transplanting red pepper seedlings. Pepper seedlings, Capsicum annuum, were transplanted on the 19th of May, 2009 and on the 20th of May, 2010, respectively. Five Yellow sticky traps were set and changed at 7 days interval. Densities of aphids and thrips and damaged fruit rates by oriental tobacco budworm, Helicoverpa assulta, were counted. CONCLUSION(S): Populations of aphids, thrips and braconid wasps were maintained high on V. tatrasperma before transplanting pepper seedlings and in early season of pepper. However, the densities of aphids on pepper in the control plot were much higher than in the cover-crop plot in the early stage of pepper. Damaged fruit rates by both of thrips and oriental tobacco budworm were not significantly different between the two experimental plots.