• Journal of Soil and Groundwater Environment
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• v.9 no.2
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• pp.11-19
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• 2004

Chlorinated and nitroaromatic compounds are non-degradable substances that are extremely toxic and are known to be carcinogens and mutation causing agents. Moreover, the half-lives of substances such as carbon tetrachloride, hexachloroethane and nitroaromatic compounds are several decades. In this study, the optimal conditions to detoxify chlorinated compounds by the reductive degradation were investigated. The following results were obtained in the reductive degradation of CCl$_4$, C$_2$Cl$\_$6/, C$_2$HCl$\_$5/, C$_2$Cl$_4$, and C$_2$HCl$\_$5/ by using Fe, FeS and FeS$_2$ as mediators. CCl$_4$ was reduced to CH$_2$Cl$_3$ and CH$_2$Cl$_2$in anaerobic conditions when FeS was used as a mediator. While the reduction of CCl$_4$ to CHCl$_3$ was rapidly proceeded, the reduction of CHCl$_3$ to CH$_2$Cl$_2$ was occurred slowly. Further reduction to CH$_3$Cl was not observed. Unlike CCl$_4$, C$_2$Cl$\_$6/ was degraded to C$_2$HCl$\_$5/, C$_2$Cl$_4$. C$_2$HCl$_3$ and cis-1,2-C$_2$H$_2$Cl$_2$ by complicated pathways such as hydrogenolysis, dehalo-elimination and dehydrohalogenation. A small amount of C$_2$HCl$\_$5/ was detected only in the early stages of the reduction. However, majority of the C$_2$Cl$\_$6/ was reduced to C$_2$Cl$_4$. cis-1,2-C$_2$H$_2$C1$_2$ was the only product among other possible isomers.

• Korean Journal of Environmental Agriculture
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• v.25 no.4
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• pp.306-315
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• 2006

Two different experiments, adsorption/desorption and runoff by rainfall simulation of four pesticides, such as alachlor, ethalfluralin, ethoprophos and pendimethalin were undertaken their runoff and erosion losses from sloped land and to assess the influence of their properties and environmental factors on them. The mobility of four pesticides and which phase they were transported by were examined in adsorption study, and the influence of rainfall pattern and sloping degree on the pesticide losses were evaluated in simulated rainfall study. Freundlich adsorption parameters (K) by the adsorption and desorption methods were 1.2 and 2.2 for ethoprophos, 1.5 and 2.6 for alachlor, respectively. And adsorption distribution coefficients (Kd) by the adsorption and desorption methods were 56 and 94 for ethalfluralin, and 104 and 189 for pendimethalin, respectively. K or Kd values of pesticides by the desorption method which were desorbed from the soil after thoroughly mixing, were higher than these ones by the adsorption method which pesticides dissolved in water were adsorbed to the soil. Another parameter (1/n), representing the linearity of adsorption, in Freundlich equation for the pesticides tested ranged from 0.96 to 1.02 by the desorption method and from 0.87 to 1.02 by the adsorption method. Therefore, the desorption method was more independent from pesticide concentration in soil solution than the adsorption method. By Soil Survey and Land Research Center (SSLRC)'s classification for pesticide mobility, alachlor and ethoprophos were classified into moderately mobile $(75{\leq}Koc<500)$, and ethalfluralin and pendimethalin were included to non-mobile class (Koc > 4000). Runoff and erosion loss of pesticides by three rainfall scenarios were from 1.0 to 6.4% and from 0.3 to 1.2% for alachlor, from 1.0 to 2.5% and from 1.7 to 10.1% for ethalfluralin, from 1.3 to 2.9% and from 3.9 to 10.8% for pendimethalin, and from 0.6 to 2.7% and from 0.1 % 0.3% for ethoprophos, respectively. Distribution of pesticides in soil profile were investigated after the simulated rainfall study. Alachlor and ethoprophos were leached to from 10 to 15 cm of soil layer, but ethalfluralin and pendimethalin were mostly remained at the top 5 cm of soil profile. The losses of the pesticides at 30% of sloping degree were from 0.2 to 1.9 times higher than those at 10%. The difference of their runoff loss was related with their concentration in runoff water while the difference of their erosion loss must be closely related with the quantity of soil eroded.

• Korean Journal of Agricultural and Forest Meteorology
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• v.13 no.2
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• pp.69-78
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• 2011

Rice is one of the world's staple foods. Paddy rice fields have unique biophysical characteristics that the rice is grown on flooded soils unlike other crops. Information on the spatial distribution of paddy fields and the timing of irrigation are of importance to determine hydrological balance and efficiency of water resource management. In this paper, we detected the timing of irrigation and spatial distribution of paddy fields using the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor onboard the NASA EOS Aqua satellite. The timing of irrigation was detected by the combined use of MODIS-based vegetation index and Land Surface Water Index (LSWI). The detected timing of irrigation showed good agreement with field observations from two flux sites in Korea and Japan. Based on the irrigation detection, a land cover map of paddy fields was generated with subsidiary information on seasonal patterns of MODIS enhanced vegetation index (EVI). When the MODISbased paddy field map was compared with a land cover map from the Ministry of Environment, Korea, it overestimated the regions with large paddies but underestimated those with small and fragmented paddies. Potential reasons for such spatial discrepancies may be attributed to coarse pixel resolution (500 m) of MODIS images, uncertainty in parameterization of threshold values for discarding forest and water pixels, and the application of LSWI threshold value developed for paddy fields in China. Nevertheless, this study showed that an improved utilization of seasonal patterns of MODIS vegetation and water-related indices could be applied in water resource management and enhanced estimation of evapotranspiration from paddy fields.

• Clinical and Experimental Pediatrics
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• v.45 no.9
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• pp.1126-1133
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• 2002

Purpose : Prader-Willi syndrome(PWS) is a complex disorder affecting multisystems with characteristic clinical features. Its genetic basis is an expression defect in the paternally derived chromosome 15q11-q13. We analyzed the clinical features and genetic basis of PWS patients for early detection and treatment. Methods : We retrospectively studied 24 patients with PWS in Department of Pediatrics, Samsung Medical Center, from September 1997 to September 2001. We performed cytogenetic and molecular genetic techniques using high resolution GTG banding techniques, fluorescent in situ hybridization and methylation-specific PCR for CpG island of SNRPN gene region. Results : The average birth weight of PWS patients was $2.67{\pm}0.47kg$ and median age at diagnosis was 1.3 years. The average height and weight of PWS patients under one year at diagnostic time were located in a 3-10 percentile relatively, and a rapid weight gain was seen between two and six years. Feeding problems in infancy and neonatal hypotonia were the two most consistently positive major criteria in over 95% of the patients. In 18 of the 24 cases(75%), deletion of chromosome 15q11-q13 was demonstrated and one case among 18 had an unbalanced 14;15 translocation. In four cases without any cytogenetic abnormality, it may be considered as maternal uniparental disomy and the rest showed another findings. Conclusion : We suggest diagnostic testing for PWS in all infants/neonates with unexplained feeding problems and hypotonia. It is necessary for clinically suspicious patients to undergo an early genetic test. As the genetic basis of PWS was heterogenous and complex, further study is required.

• Journal of Korean Society for Atmospheric Environment
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• v.10 no.E
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• pp.332-342
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• 1994

Hierarchical cluster and factor analyses were used to identify various influences on free tropospheric air samples at Mauna Loa Observatory in Hawaii during MLOPEX. The cluster analysis separated thirteen chemical and meteorological variables into three characteristic groups (1)clean air, (2)anthropogenically influenced air, (3)marine and volcanic influenced air. The cluster analysis results compared well with those of factor analysis. Six independent components were identified in factor analysis. We have related these components to (1)volcano influenced air, (2)stratosphere-like air, (3)boundary-layer air with recent anthropogenic influence, (4)photochemical haze, (5)marine boundary- layer air, and (6)modified marine tropospheric air. Excluding local influence, we could calculate the nighttime free tropospheric values for $O_3$(41$\pm$10 ppbv), HN $O_3$(94$\pm$45 pptv), N $O_3$$^{[-10]}$ (16$\pm$10 ppbv), S $O_4$$^{[-10]}$ (60$\pm$0 pptv), N $H_4$$^{＋}$(71$\pm$6 pptv), N $a^{＋}$(5$\pm$1 pptv), PAN(13$\pm$9 pptv), MeN $O_3$(3.5$\pm$1.5 pptv), 2-butyl N $O_3$(0.6$\pm$0.1 pptv), $H_2O$$_2$(1015$\pm$44 pptv), $C_2$C $l_4$(3.3$\pm$0.1 pptv), condensation nuclei(249$\pm$13c $m^{-3}$), and dew point(-8.5$\pm$5.3$^{\circ}C$) during this experiment..

• Radiation Oncology Journal
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• v.20 no.4
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• pp.381-390
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• 2002

Purpose : To develop a dose calibration program for the IAEA TRS-277 and AAPM TG-21, based on the air kerma calibration factor (or the cavity-gas calibration factor), as well as for the IAEA TRS-398 and the AAPM TG-51, based on the absorbed dose to water calibration factor, so as to avoid the unwanted error associated with these calculation procedures. Materials and Methods : Currently, the most widely used dosimetry Protocols of high energy photon beams are the air kerma calibration factor based on the IAEA TRS-277 and the AAPM TG-21. However, this has somewhat complex formalism and limitations for the improvement of the accuracy due to uncertainties of the physical quantities. Recently, the IAEA and the AAPM published the absorbed dose to water calibration factor based, on the IAEA TRS-398 and the AAPM TG-51. The formalism and physical parameters were strictly applied to these four dose calibration programs. The tables and graphs of physical data and the information for ion chambers were numericalized for their incorporation into a database. These programs were developed user to be friendly, with the Visual $C^{++}$ language for their ease of use in a Windows environment according to the recommendation of each protocols. Results : The dose calibration programs for the high energy photon beams, developed for the four protocols, allow the input of informations about a dosimetry system, the characteristics of the beam quality, the measurement conditions and dosimetry results, to enable the minimization of any inter-user variations and errors, during the calculation procedure. Also, it was possible to compare the absorbed dose to water data of the four different protocols at a single reference points. Conclusion : Since this program expressed information in numerical and data-based forms for the physical parameter tables, graphs and of the ion chambers, the error associated with the procedures and different user could be solved. It was possible to analyze and compare the major difference for each dosimetry protocol, since the program was designed to be user friendly and to accurately calculate the correction factors and absorbed dose. It is expected that accurate dose calculations in high energy photon beams can be made by the users for selecting and performing the appropriate dosimetry protocol.

• Journal of Veterinary Clinics
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• v.27 no.5
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• pp.533-539
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• 2010

Stem cell-based therapy is under intensive investigation to treat acute renal failure (ARF). The purpose of this study was to evaluate available ARF models, and suggest a model appropriate to therapeutic evaluation of the stem cells in preclinical approach by determining the optimum concentration of nephrotoxic agents and duration of ischemia induction. Three different types of available acute kidney injury (AKI) animal models were analyzed using rats: Cisplatin (saline, 5 and 7.5 mg/kg, IP) or glycerol (saline, 8 and 10 ml/kg, IM)-induced nephrotoxicity as toxic models and ischemia-induced (sham, 35 and 45 minutes) nephropathy as an ischemic model. The relevance and applicability to investigate especially the regenerative ability of stem cells were evaluated regarding morphology, renal function and survival at this time point. In the point of renal function, 10 ml glycerol/kg and 7.5 mg cisplatin/kg model in toxic models and 45 min model in ischemia models showed significant decrease for the longer observation time compared to 8 ml glycerol/kg, 5 mg cisplatin/kg and the 35 min ischemia models, respectively. All groups were observed no mortality except 45 min-ischemia model with 50% survival. Histological significant alterations including cast formation in the tubular lumen, tubular necrosis and apoptosis were revealed on the second day in either ischemiaor glycerol-induced models, and on day 5 in cisplatin-induced models. The results indicate that ischemia 35 min-, cisplatin 7.5 mg/kg- and glycerol 10 ml/kg-induced AKI would be ideal animal models to monitor a outcome parameter related to the therapeutic effects on renal function with noninvasive techniques in the same animal at multiple time points. Our findings also suggest that the best time points for the functional or histological interpretation of renal will be on day 2 in both glycerol- and ischemia-induced AKI models and on day 5 in cisplatin-induced AKI.

• Cartoon and Animation Studies
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• s.46
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• pp.85-106
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• 2017

With the media's shift into the digital era in the 2000s, comic book publishers attempted a transition into the new medium by establishing a distribution structure using internet networks. But that effort shied from escaping the parallel-page reading structure of traditional comics. On the other hand, webtoons are showing divers changes by redesigning the structure of traditional sequential art media; they tend to separate and allot spaces according to the vertical scroll reading method of the internet browser and include animations, sound effects and background music. This trend is also in accordance with the preferences of modern readers. Modern society has complicated social structures with the development of various media; the public is therefore exposed to different stimuli and shows characteristics of differentiated perceptions. In other words, webtoons display more relevant and entertaining characteristics by inserting sounds and using moving texts and characters in specific frames, while traditional comics require an appreciation of withdrawal and immersion like other published media. Motions in webtoons are partially applied for dramatic tension or to create an effective expression of action. For example, hand-drawn animation is adopted to express motions by dividing motion images into many layers. Sounds are also utilized, such as background music with episode-related lyrics, melodies, ambient sounds and motion-related sound effects. In addition, webtoons provide readers with new amusement by giving tactile stimuli via the vibration of a smart phone. As stated above, the vertical direction, time-based nature of animation motions and tactile stimuli used in webtoons are differentiated from published comics. However, webtoons' utilization of innovative techniques hasn't yet reached its full potential. In addition to the fact that the software used for webtoon effects is operationally complex, this is a transitional phenomenon since there is still a lack of technical understanding of animation and sound application amongst the general public. For example, a sound might be programmed to play when a specific frame scrolls into view on the monitor, but the frame may be scrolled faster or slower than the author intended; in this case, sound can end before or after a reader sees the whole image. The motion of each frame is also programmed to start in a similar fashion. Therefore, a reader's scroll speed is related to the motion's speed. For this reason, motions might miss the intended timing and be unnatural because they are played out of context. Also, finished sound effects can disturb the concentration of readers. These problems come from a shortage of continuity; to solve these, naturally activated consecutive sounds or animations, like the simple rotation of joints when a character moves, is required.

• Journal of the Korean earth science society
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• v.30 no.6
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• pp.699-708
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• 2009

Recently as the interest in the development of domestic ore deposits has increased, we can easily find some studies on exploration geophysics-based ore-deposit survey in literature. Based on the fact that mineralized zone are generally more conductive than surrounding media, electrical resistivity survey among several geophysical surveys has been applied to investigate metallic ore deposits. Most of them are grounded on 2-D survey. However, 2-D inversion may lead to some misinterpretation for 3-D geological structures. In this study, we investigate the feasibility of the 3-D electrical resistivity survey to 3-D vein-type ore deposits. We first simulate 2-D dipole-dipole survey data for survey lines normal to the strike and 3-D pole-pole survey data, and then perform 3-D inversion. For 3-D ore-body structures, we assume a width-varying dyke, a wedge-shaped, and a fault model. The 3-D inversion results are compared to 2-D inversion results. By comparing 3-D inversion results for 2-D dipole-dipole survey data to 3-D inversion results for 3-D pole-pole survey data, we could note that the 2-D dipole-dipole survey data yield better inversion results than the 3-D pole-pole data, which is due to the main characteristic of the pole-pole array. From these results, we are convinced that if we have certain information on the direction of the strike, it would be desirable to apply 2-D dipole-diple survey for the survey lines normal to the strike. However, in most cases, we do not have any information on the direction of the strike, because we already developed the ore deposit with the outcrops and the remaining ore deposits are buried under the surface. In that case, performing 3-D pole-pole electrical resistivity survey would be a reasonable choice to obtain more accurate interpretation on ore body structure in spite of low resolution of pole-pole array.

• The Korean Journal of Air & Space Law and Policy
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• v.25 no.1
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• pp.159-203
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• 2010

Together with the development of space science outer space law has become one of the most rapidly developing branches of international law. This reflects a general realization that these new activities must be subject to reasonable legal regulation if they are to serve the peaceful purposes of mankind without undue confusion and disorder. The exploration and use of outer space introduces many novel opportunities and dilemmas, and inspired insights are needed in the development of this new resource. In particular, the settlement of space law disputes is a relatively new discussion in international law. However, the significance of the settlement of space law disputes was acknowledged in various colloquia organized by legal academicians and practitioners around the world. Analysis of the dispute settlement provisions in space agreements plainly reveals the degree to which States persist to be mistrustful of any impingement to their sovereignty. They are reluctant to submit disputes to adjudication and binding arbitration, particularly when these provisions are negotiated between States which have dissimilar political, economic and social interests and demography. However, there is a slow but clear shift in this attitude as States realize the contemporary political, economic and technical pressures necessitating the lifting of the veil of State sovereignty. The development of an effective mechanism for the settlement of disputes arising in relation to the development of the exploration and exploitation of outer space has been the subject of global study by highly qualified publicists and international institutions. The 1972 Liability Convention is the space treaty with the most elaborate provisions for dispute settlement. However, it fails to ensure binding decisions. In this point, the 1998 Taipei Final Draft Convention may be a useful instrument for further consideration on whether an independent sectorialized dispute settlement mechanism should be established. Considering these circumstances it seemed essential to take legislative action to implement a system as comprehensive as the relevant legal framework are in the Law of the Sea and International Criminal Law mechanisms for dispute settlement and conflict avoidance from outer space activities.