• Economic and Environmental Geology
• /
• v.41 no.1
• /
• pp.81-92
• /
• 2008

Fonualei Rift and Spreading Center(FRSC) and Mangatolu Triple function(MTJ) caldera are located in northeastern part of Lau basin which is the active back-arc basin. Deep-tow and surface-tow magnetic surveys are carried out in FRSC. In deep-tow magnetic survey, to compensate for influence of uneven distance between bathymetry and sensor height, magnetic anomaly is continued upward to a level plane by using the Guspi method. We calculate crustal magnetization using Parker and Huestis's inversion algorithm, and try to find the hydrothermal vent and understand the structure of ocean floor crust. The result of deep-tow magnetic survey at FRSC showed that Central Anomaly Magnetization High(CAMH) recorded the max value of 4.5 A/m which is associated with active ridge. The direction of SSW-NNE corresponds with the direction of the principal spreading ridge in Lau basin. The low crustal magnetizaton$(174^{\circ}35.1'W,\;16^{\circ}38.4'S)$ of -4.0 A/m is supposed to correlate with submarine hydrothermal vent. Surface-tow magnetic data were collected in MTJ caldera$(174^{\circ}00'W,\;15^{\circ}20'S)$. The prevailing SSW-NNE direction of collapsing walls and the presence of CAMH at the center of caldera strongly indicate the existence of active spreading ridge in ancient times.

• Korean Journal of Environmental Agriculture
• /
• v.13 no.1
• /
• pp.10-17
• /
• 1994

To investigate differences with the polluted sources on Cu contents in soils and paddy rices under water pollutions, soils with the distance, the surface(0-15㎝ depth) and subsurface(15-30㎝ depth) in 1982 and 1990, and rice plants at the soil sampling sites in 1990 were separately sample at Mangyeong River area under the influence of municipal and industrial waste water from Jeonju city. Soil samples were extracted with $4M-HNO_3$ and plant samples were digested with mixture of $HNO_3$ and $HClO_4$ for analyzing Cu, Cd, Zn, Pb by atomic absorption spectrophotometry. Cu contents in soils ranged from 5.20 to 71.70 mg $kg^{-1}$. Average Cu level in 1990 was higher than that in 1982. Variation of Cu content with the distances from the source of waste water in 1990 was more regularly decreased than that in 1982. A significant correlation was observed between Cu contents in leaf sheath of rice plant and Cu, Zn and Pb contents in soils. Cu contents in soil was correlated with Zn and Pb in soil at area affected by waste water, regardless of years and soil depths. Cu contents in brown rice ranged from 0.4 to 10 mg $kg^{-1}$, and it was the lowest in parts of rice plant, and Cu content in panicle axis was 2.3 times higher than that in brown rice.

• Journal of Astronomy and Space Sciences
• /
• v.14 no.2
• /
• pp.330-346
• /
• 1997

Korea Multi-Purpose Satellite I (KOMPSAT-I, the first multi-purpose Korean satellite) will be launched in the third quarter of 1999, which is operated on the sun-synchronous orbit for cartography, ocean color monitoring, and space environment monitoring. The main mission of Electro-Optical Camera(EOC) which is one of KOMPSAT-I sensors is to provide images for the production of scale maps of Korea. EOC collects panchromatic imagery with the ground sample distance of 6.6m at nadir through visible spectral band of 510~730nm. For determining KOMPSAT-I crossing time over Korea, this study examines the diurnal variation of solar and atmospheric variables that can exert a great influence on the EOC imagery. The results are as follows: 1) After 10:30 a.m. at the winter solstice, solar zenith angle is less than $70^{\circ}$ and expected flux of EOC spectral band over land for clear sky is greater than about $2.4mW/cm^2$. 2) For daytime the distribution of cloud cover (clear sky) shows minimum (maximum) at about 11:00 a.m. Although the occurrence frequency of poor visibility by fog decreases from early morning toward noon, its effect on the distribution of clear sky is negligible. From the above examination it is concluded that determining KOMPSAT-I crossing time over Korea between 10:30 and 11:30 a.m. is adequate.

• Science of Emotion and Sensibility
• /
• v.17 no.2
• /
• pp.91-100
• /
• 2014

This study was to examine how visual angle of matrix corresponding to the physical properties of P300 speller and eye gaze corresponding to the user's personal characteristics influence on the accuracy of P300. Visual angle of the matrix was operated as the distance between the user and the matrix and three groups were composed: 60 cm group, 100 cm groups, and 150 cm group. Eye gaze methods was consisted three conditions. Head moving condition was putting eye gaze using head, pupil moving condition was moving pupil with the head fixed, while the eye fixed condition is to fix the eye gaze at the center of the matrix. The results showed that there was significant difference in the accuracy of P300 speller according to the eye gaze method. The accuracy of the head moving condition was higher than the accuracy of pupil moving conditions, accuracy of pupil moving conditions was higher than the accuracy of the eye fixed conditions. However, the effect of visual angle of matrix and interaction effect were not significant. When P300 amplitude of target character was measured depending on how you stare at the target character, P300 amplitude of the head moving condition was greater than P300 amplitude of the pupil moving condition. There was no significant difference in the error distribution in head moving condition and pupil moving condition, while there was a significant difference between two eye gaze conditions and fixed gaze condition. The error was located at the neighboring characters of the target character in head moving condition and pupil moving condition, while the error was relatively distributed widely in fixed eye condition, error was occurred with high rate in characters far away from the center of matrix.

• Korean Journal of Remote Sensing
• /
• v.32 no.6
• /
• pp.551-566
• /
• 2016

In the satellite remote sensing, the operational environment of the satellite sensor causes image degradation during the image acquisition. The degradation results in noise and blurring which badly affect identification and extraction of useful information in image data. Especially, the degradation gives bad influence in the analysis of images collected over the scene with complicate surface structure such as urban area. This study proposes a multi-stage image restoration to improve the accuracy of detailed analysis for the images collected over the complicate scene. The proposed method assumes a Gaussian additive noise, Markov random field of spatial continuity, and blurring proportional to the distance between the pixels. Point-Jacobian Iteration Maximum A Posteriori (PJI-MAP) estimation is employed to restore a degraded image. The multi-stage process includes the image segmentation performing region merging after pixel-linking. A dissimilarity coefficient combining homogeneity and contrast is proposed for image segmentation. In this study, the proposed method was quantitatively evaluated using simulation data and was also applied to the two panchromatic images of super-high resolution: Dubaisat-2 data of 1m resolution from LA, USA and KOMPSAT3 data of 0.7 m resolution from Daejeon in the Korean peninsula. The experimental results imply that it can improve analytical accuracy in the application of remote sensing high resolution panchromatic imagery.

• Korean Journal of Ecology and Environment
• /
• v.34 no.2 s.94
• /
• pp.119-125
• /
• 2001

Total bacterial density was investigated in the main stream and tributaries of the Kyongan Stream and inlet parts of Paltang Reservoir from September 2000 to February 2001 by acridine orange direct count (AODC) method. Total bacterial number in the Kyongan Stream was mainly under influence of the effluent discharge of sewage wastewater treatment plant (SWTP) located in the upstream or downstream. Decreasing rate with water flowing distance (km) in the main stream is $0.13\;{\time}\;10^6$ cells/ml, and it was estimated to much accumulating quantity on the stream bed during transport to downstream. Average values of total bacterial number in September${\sim}$October, November and December${\sim}$February were range $1.74{\sim}3.10{\time}10^6$, $1.86{\sim}7.30{\time}10^6$ and $4.56{\sim}8.75{\time}10^6$cells/ml, respectively, and were high at low temperature than that of high temperature period. Total bacterial number was more abundant at below $10^{\circ}C$ with $2.1{\sim}3.0$ folds than at above $10^{\circ}C$. Water quality by total bacterial number was classify to eutrophic and the potential of wastewater treated effluent for the microbial contamination assessed to very high. The results of this study indicate that the management of point source, SWTP effluent, is urgent to mitigate bacterial impact of Paltang Reservoir as well as the Kyongan Stream.

• Archives of Plastic Surgery
• /
• v.38 no.2
• /
• pp.173-181
• /
• 2011

Purpose: Masseter muscle is an important muscle of mastication. Because it has a great influence on the shape of low facial contour, patients who have masseteric hypertrophy show square-shaped jaw appearance. As aesthetic procedures for the reduction of the masseter muscle volume, radiofrequency ablation or botulinum toxin injection is at the center of attention. Authors studied the anatomical measurement of the thickness and width of masseter muscle and the surface mapping of the maximal thickness point using computed tomography (CT) scan to identify the useful guide for the injection of botulinum toxin in masseteric hypertrophy patients. Methods: We analyzed 2 mm-thickness OMU (ostiomeatal unit) CT of 112 normal people (224 masseter muscles) taken from June 2009 to May 2010. First, we measured the thickness, width and depth of the masseter muscle from the skin surface and analysed each by side, sex and age, respectively. The distribution of the thickness of the muscle and the correlation of thickness and width of the muscle were studied also. Second, we underwent surface mapping of the maximal thickness point using CT analysis by means of checking the vertical and horizontal distance from the angle of the mandible. Results: The average thickness and width of the masseter muscle was 17.73 mm and 40.78 mm in the male patients and were 14.33 mm and 37.42 mm in the female patients. Statistically, both figures of the male patients were larger than those of the female patients. However, the depth of the muscle from the skin surface in female patients (7.37 mm) was larger than that of the male patients (6.15 mm). There were no statistical difference in side or age. The width and thickness of the masseter muscle were in the positive correlation. The location of maximal thickness point of the masseter muscle was 27.77 mm vertically and 27.68 mm horizontally in the male patients, and 25.19 mm vertically and 25.42 mm horizontally in the female patients from the angle of mandible. Conclusion: We were able to present statistical evidence of the diagnosis and treatment of the masseteric hypertrophy regarding the anatomical measurements such as the thickness and width. And the maximal thickness point of the masseter muscle may be a useful guide for the clinical procedures of botulinum toxin injection.

• International Journal of Automotive Technology
• /
• v.4 no.2
• /
• pp.77-86
• /
• 2003

How to compare the environmental damage caused by vehicles with different foe]s and drive trains\ulcorner This paper describes a methodology to assess the environmental impact of vehicles, using different approaches, and evaluating their benefits and limitations. Rating systems are analysed as tools to compare the environmental impact of vehicles, allowing decision makers to dedicate their financial and non-financial policies and support measures in function of the ecological damage. The paper is based on the "Clean Vehicles" research project, commissioned by the Brussels Capital Region via the BIM-IBGE (Brussels Institute for the Conservation of the Environment) (Van Mierlo et at., 2001). The VriJe Universiteit Brussel (ETEC) and the universite Libre do Bruxelles (CEESE) have jointly carried out the workprogramme. The most important results of this project are illustrated in this paper. First an overview of environmental, economical and technical characteristics of the different alternative fuels and drive trains is given. Afterward the basic principles to identify the environmental impact of cars are described. An outline of the considered emissions and their environmental impact leads to the definition of the calculation method, named Ecoscore. A rather simple and pragmatic approach would be stating that all alternative fuelled vehicles (LPG, CNG, EV, HEV, etc.) can be considered as ′clean′. Another basic approach is considering as ′clean′ all vehicles satisfying a stringent omission regulation like EURO IV or EEV. Such approaches however don′t tell anything about the real environmental damage of the vehicles. In the paper we describe "how should the environmental impact of vehicles be defined\ulcorner", including parameters affecting the emissions of vehicles and their influence on human beings and on the environment and "how could it be defined \ulcorner", taking into account the availability of accurate and reliable data. We take into account different damages (acid rain, photochemical air pollution, global warming. noise, etc.) and their impacts on several receptors like human beings (e.g., cancer, respiratory diseases, etc), ecosystems, or buildings. The presented methodology is based on a kind of Life Cycle Assessment (LCA) in which the contribution of all emissions to a certain damage are considered (e.g. using Exposure-Response damage function). The emissions will include oil extraction, transportation refinery, electricity production, distribution, (Well-to-Wheel approach), as well as the emission due to the production, use and dismantling of the vehicle (Cradle-to-Grave approach). The different damages will be normalized to be able to make a comparison. Hence a reference value (determined by the reference vehicle chosen) will be defined as a target value (the normalized value will thus measure a kind of Distance to Target). The contribution of the different normalized damages to a single value "Ecoscore" will be based on a panel weighting method. Some examples of the calculation of the Ecoscore for different alternative fuels and drive trains will be calculated as an illustration of the methodology.

• Economic and Environmental Geology
• /
• v.53 no.4
• /
• pp.397-411
• /
• 2020

The Cretaceous Yucheon Group is volcano-sedimentary successions that are formed by volcanic activities of the Gyeongsang Volcanic Arc. Lack of the detailed field researches on the Yucheon Group results in poor understanding of the formation time and the tempo-spatial development of the volcanic arc. Also, this causes difficulties to reconstruct the depositional history from the Sindong and Hayang groups to the Yucheon Group. In this study, we conducted field research targeting to the interface between topmost part of the Hayang Group and the lowermost part of the Yucheon Group from Hyeonpoong to Bugok areas. We also identified depositional timing of the lowermost part of the Yucheon Group using SHRIMP U-Pb zircon age dating. This Yucheon Group is composed of tuff and lapilli tuff, conformably overlying the Jindong Formation. The results of SHRIMP U-Pb zircon age are 97 to 96 Ma, indicating cessation of deposition of the Hayang Group at 97 to 96 Ma by input of pyroclastic materials into the Jinju Subbasin during the explosive volcanic eruptions from the Gyeongsang Volcanic Arc. In comparison with field researches and results of LA-ICP-MS zircon U-Pb age dating (88-85 Ma) of the lowermost part of the Yucheon Group in Gyeongju areas, the volcanic activities that formed Yucheon Group and their influence ranges varied tempo-spatially. This is probably due to distance difference from the volcanic arc or establishment of the paleo-drainage system from the Gyeongsang Volcanic Arc to nearby lowlands.

• Transactions of the Korean hydrogen and new energy society
• /
• v.9 no.4
• /
• pp.151-160
• /
• 1998

The variation of the hydrogen-storage properties of Mg contained in the mechanically-allyed mixture with the weight percentage of nickel in the sample is investigated. The weight percentage of nickel transformed into the Mg2Ni phase, on the basis of the nickel weight, is highest in the Mg-10 wt.%Ni sample. For the first hydriding cycle, the effect of mechanical alloying on the hydriding rate of Mg is highest in the Mg-25 wt.%Ni sample. After activation, the effects of mechanical alloying and hydriding-dehydriding cycling on the hydriding rate of Mg are highest in the Mg-10 wt.%Ni sample. After sufficient hydriding-dehydriding cycling, the effects on the hydrogen-storage capacity of Mg are highest in the Mg-10 wt.%Ni sample. The effects on the hydriding and dehydriding rates of Mg are highest in the Mg-25wt.%Ni sample. Mg-25wt.%Ni, followed by Mg-10 wt.%Ni, is the optimum composition which has the best effects on the hydrogen-storage properties of Mg contained in the sample. The mechanical alloying and the hydriding-dehydriding cycling produce many defects, which can act as active nucleation sites, and increase the specific surface area, shortening the diffusion distance of hydrogen.