• International Journal of Highway Engineering
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• v.7 no.4 s.26
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• pp.163-171
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• 2005

Current roads were designed and constructed based on the design criteria and thus those were overly simplified drivers' needs. The road criteria do not suggest the desirable range of the design values but suggest the minimum requirements for the road design. Therefore, a completed road design based on the design criteria does not always guarantee the best design in terms of safety and it sometimes violates drivers' expectation. Therefore, the ROSSAV(ROad Safety Survey and Analysis Vehicle) is being developed by the KICT to evaluate road safety and increase driving safety. In this paper, the image capture system was described in detail. The image capture system is consisted of two front view cameras, two side down-looking cameras and a synchronization device. Two front view cameras were used to take a picture of road and road facilities at the driver's viewpoint. Also, two side down-looking cameras were used to capture road surface image to extract lane markings. A synchronization device were used to generate image capturing signal at the fixed distance spacing huck as every 10m. The front view images could be used to calculate and measure highway geometry such as shoulder width because every image is saved with it's locational information. And also the side down looking images could be used to extract median lane mark which representing road alignement efficiently.

• Applied Chemistry for Engineering
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• v.8 no.4
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• pp.568-574
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• 1997

The effect of microencapsulation of maetal hydride (MH) with copper on the electrode performance of a Ni/MH battery has been investigated. The MH electrodes were prepared with a combination of cold press and paste methods. The discharge capacity of the electrode increased with an addition of small amounts if CMC into the electrode, but decreased when heat-treated in an oxygen-free nitrogen flow. The capacity of a Cu-coated $LaNi_5$ electrode was higher than that of LaNi5electrode. The discharge capacity of the electrode prepared with Cu-coated $LaNi_5$ increased with the increase of copper content in the electrode. It is considered that the increase of copper content enhanced the current density on the electrode surface, leading to the increase of the discharge capacity The MH electrode coated by an acidic electroless plating method showed much higher discharge capacity than that using an alkaline electroless plating method. The discharge capacity of the $LaNi_{4.5}Al_{0.5}$ electrode was higher than that of the $LaNi_5$ electrode. Also, the effect of microencapsulation on the deactivation of $LaNi_5$ was studied using an absorption-desorption cycle in CO-containing hydrogen.

• Journal of the Korean Geographical Society
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• v.49 no.2
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• pp.200-220
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• 2014

This study reexamines the old concept and reviews prevalent statements on Cenozoic vertical motions of the peninsula that have been uncritically repeated in our academia. The contents of this paper are redefinition of the notion, tilted flexure or warping, and a suggestion for a new time set and properties of the deformation, followed by a new model on its influencing factors and processes. In conclusion, the Cenozoic vertical motion of the Korean peninsula can be reified further with an epeirogenic movement of uplift in the east side-subsidence in the west side of the peninsula since the Neogene (23 Ma). However, the regional boundary for areas of uplift and subsidence is not likely in the Korean peninsula but broader farther to East China and the southern part of Russia. It can be best understood that mantle convection produced by subducting activities in the Western Pacific Subduction Zone causes the uplift and subsidence of earth surface around NE Asia. In addition, faultings in the upper lithosphere induced by in-situ plate boundary stresses accelerate regional uplift in the peninsula since the Quaternary. Controversies that are still standing such as current uplift movements along the western coast of the peninsula during the late Quaternary could be precisely discussed with future research providing detailed information on it.

• Journal of Hydrogen and New Energy
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• v.7 no.1
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• pp.45-54
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• 1996

Electrochemical oxidation of hydrogen on PdOx and Pd electrodes were investigated in aqueous 30% KOH solution at different temperatures and hydrogen concentrations(partial pressures). Anodic reaction by hydrogen on PdOx electrode was mainly due to the oxidation of adsorbed hydrogen at -0.8V~-0.5V(vs. Hg/HgO). For Pd electrode, the anodic reaction was participated by the adsorbed hydrogen on surface, as well as by the metal hydride formed from direct reaction between Pd and hydrogen at -0.5V~0.0V(vs. Hg/HgO). With the increase of hydrogen concentration the charge transfer resistance decreased and the exchange current increased. The transfer coefficient of PdOx and Pd electrodes were found to be 0.78 and 0.72 respectively, which shows the superior reactivity of Pd electrode. The activation energies of PdOx and Pd electrodes decreased with the increase of overpotential and were found to be 23.9~20.3 kJ/mole and 7.2~3.0kJ/mole, respectively.

• Journal of Environmental Science International
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• v.18 no.12
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• pp.1437-1442
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• 2009

Recent studies have shown that alum addition to litter results in many environmental and economic advantages, such as reductions in metal runoff, lower ammonia emission and improved poultry performance. However, no research has been conducted to evaluate the effects of different types of alum on soluble metals in poultry litter. The objective of this study was conducted to investigate changes in soluble metal from poultry litter with different types of aluminum sulfate (alum) under laboratory condition. The treatments used in this study, which were mixed in the upper 1 cm of litter or sprayed onto the litter surface, were 4 g alum, 8 g alum, 8.66 g liquid alum, 17.3 g liquid alum, 11.2 g A7 (high acid alum), and 22.4 g A7 (high acid alum)/100 g litter. Applying different types of alum to poultry litter reduced (P<0.05) concentrations of soluble Fe (9 to 54%), Cu (9 to 49%) and Zn (11 to 40%), relative to untreated litter, whereas it increased Ca and Mg (P<0.05). Mean soluble Fe and Cu levels in poultry litter from different types of alum decreased in the order: 22.4 g A7 (54% and 49%) > 17.3 g liquid alum (48% and 42%) > 8 g alum (48% and 31%) > 4 g alum (28% and 10%) > 8.6 g liquid alum (10% and 9%) > 11.2 g A7 (8.6% and 9%). Additionally, the high reduction in soluble Zn concentration was 4 g alum (40%), followed by 8 g alum (26%), 22.4 g A7 (25%), 17.3 g liquid alum (23%), 8.66 g liquid alum (18%), and 11.2 g A7 (11%), respectively. In conclusion, the current studies suggest that treating poultry litter with different types of alum can be applied to reduce soluble metal (Fe, Cu, and Zn) and to develop a production to merchandise for poultry litter that would result in reduction in pollutants from these materials. Furthermore, in order to improve environmental management in the poultry industry, the use of alum, liquid alum and high acid alum all should be provided a valid means of reducing negative environmental impact.

• Journal of the Korean earth science society
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• v.36 no.6
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• pp.520-532
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• 2015

In order to understand the Holocene sea level changes in the eastern Yellow Sea, the west coast of Korea, and to compare the rates of sea level rise in each period of time, the geological proxy records for pre-instrumental era and measurement data for the present day were combined and analysed. The sea level in the Yellow Sea rose fast with a rate of about 10 mm/yr during the early Holocene, and decelerated down to 1 mm/yr since the mid to late Holocene. The rising rates of sea level in the 20th century were slightly higher than those in the late Holocene. The present-day rates of sea level rise, known as the 'rapid' rise, are in fact much lower or similar, compared to the early to mid Holocene sea levels in the study area. Recent tide-gauge data show that sea level rise in the eastern Yellow Sea has been accelerating toward the 21st century. These rising trends coincide well with global rising patterns in sea level. Additionally, the present-day rising trends of sea level in this study are correlated with increased rates of carbon dioxide concentrations and sea surface temperatures, further indicating a signal to global warming associated with the human effect. Thus, the sea level changes induced by current global warming observed in the eastern Yellow Sea and world's oceans can be considered as 'Anthropocene' sea level changes. The changes in sea level are based on instrumental measurements such as tide-gauges and satellite altimetry, meaning the instrumental era. The Holocene changes in sea level can thus be reconstructed from geological proxy records, whereas the Anthropocene sea-level changes can be solely based on instrumental measurements.

• Journal of the Korean earth science society
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• v.34 no.7
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• pp.669-680
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• 2013

Ozone sensitivity analysis with respect to $NO_x$ is conducted around the south-eastern area of the Korean Peninsula. WRF-CMAQ modeling system is used to simulate a local circulation and high ozone episode day. To analyze the sensitivity, the adjoint model for CMAQ is adopted in this study. The purpose of current study is to investigate the location that affects a day time ozone concentration of these receptors on the high ozone episode day. Adjoint sensitivity analysis for Daegu shows two areas of influence. One is the range from the neighboring location to Pohang and it affects mainly on the same day as receptor time. The other is the remote south-eastern area from Daegu. This remote influence area suggests that $NO_x$ emitted on the previous day can change the ozone concentration at receptor time. The influence area for Busan, on the other hand, is originated only from the emission on the previous day because the sea-breeze occurred on the episode day makes low influence of surrounding emission. The cross sectional analysis reveals that $NO_x$ advection is important not only near the surface of land but also around the height of boundary layer.

• Journal of Periodontal and Implant Science
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• v.33 no.1
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• pp.1-11
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• 2003

Hydroxyapatite(HA) has been extensively used as bone graft materials and tooth implant surface coating materials because of its biocompatibility and osteoconductive properties. However, as HA is intrinsically poor in mechanical properties, zirconia($ZrO_2$) was incorporated with HA as reinforcing phases for improvement of mechanical properties. The purpose of this study was to investigate the biological activities of HA-coated zirconia through the cell proliferation test, measurements of alkaline phosphatase activity, and histologic examination. Four kinds of tested blocks were prepared according to the pore size (300-500${\mu}m$/500-700${\mu}m$) and the porosity (70%/90%). Cell proliferation and alkaline phosphatase activity was measured at 1, 7, 14 days. The number of cells proliferate after 7, 14 days were significantly increased in all groups when compared with that of the first day, but there was no significant difference between the 4 groups at each time period. At the 7 day, alkaline phosphatase activities of cells cultured in 4 groups were higher than that of the first day, but there was no significant difference between the 4 groups at each time period. The human gingival fibroblast and MG 63 cell was used to evaluate the cell cytotoxicity using MTT test. The materials tested in the current study turned out to be non-cytotoxic. In histologic examination(SEM), at 1 day there were many cells attached on the surfaces of all kinds of tested blocks. The number of cells were increased over time. At the 14 day, there were more cells proliferated than 1 day and some of the pores of blocks were partially filled with the proliferated cells. The in vitro response of osteoblast-like cells to the HA-coated zirconia showed comparable effect on transformation comparable to hydroxyapatite.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07b
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• pp.851-856
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• 2003

We have investigated the material and electrical properties of $Bi_{4-x}La_xTi_3O_{12}$ (BLT) ferroelectric thin film for ferroelectric nonvolatile memory applications of capacitor type and single transistor type. The 120nm thick BLT films were deposited on $Pt/Ti/SiO_2/Si$ and $SiO_2/Nitride/SiO_2$ (ONO) substrates by the sol-gel spin coating method and were annealed at $700^{\circ}C$. It was observed that the crystallographic orientation of BLT thin films were strongly affected by the excess Bi content and the intermediate rapid thermal annealing (RTA) treatment conditions regardeless of two type substrates. However, the surface microstructure and roughness of BLT films showed dependence of two different type substrates with orientation of (111) plane and amorphous phase. As increase excess Bi content, the crystallographic orientation of the BLT films varied drastically in BLT films and exhibited well-crystallized phase. Also, the conversion of crystallographic orientation at intermediate RTA temperature of above $450^{\circ}C$ started to be observed in BLT thin films with above excess 6.5% Bi content and the rms roughness of films is decreased. We found that the electrical properties of BLT films such as the P-V hysteresis loop and leakage current were effectively modulated by the crystallographic orientations change of thin films.

• Journal of the Korea Concrete Institute
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• v.19 no.2
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• pp.189-197
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• 2007

Concrete tunnel lining must be designed to having the fireproof performance because the lining are sometimes exposed to very high temperature due to traffic accident. Such fire temperature may cause explosion of concrete, or collapse of tunnel structure. The purpose of this study is to obtain the fundamental fireproof behavior of fire resistance-engineered cementitious composites(FR-ECC) under fire temperature in order to use the fire protection material in tunnel lining system. The present study conducted the experiment to simulate fire temperature by employing 2 types of FR-ECC and investigated experimentally the explosion and cracks in heated surface of these FR-ECC. Employed temperature curve were hydro carbon(HC, ECl) criterion, which are severe in various criterion of fire temperature. The numerical analysis is carried out the nonlinear transient heat flow analysis and verified against the experimental data. The complex features of behavior in fire conditions, such as thermal expansion, plasticity, cracking or crushing, and material properties changing with temperature are considered. By the use of analytical model, the concrete tunnel subjected to fire loads were analyzed and discussed. With comparison of current concrete materials and FR-ECC, the experimental and analytical results of FR-ECC shows the better fire resistance performance than the other.