• Journal of Oral Medicine and Pain
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• v.25 no.1
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• pp.41-51
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• 2000

This study was performed to investigate the effect of three modalities commonly used for reduction of oral malodor and to review the contributing factors for halitosis. For this study, 45 subjects of good general health in their third decades were selected, and they were divided into three groups by each modality, that is, tongue scraping, $ZnCl_2$ mouth rinse, and periodontal treatment. Subjective sense of halitosis, diets, Oral hygiene index based on tooth brushing and tongue brushing habit, resting salivary flow rate, gingival index, degree of tongue coating were recored in the Halito-Chart designed by the author. Oral malodor converted from volatile sulfur compound was measured by the Halimeter$^{(R)}$(Interscan Co., USA), and the correlation between the oral factors and pre-treatment halimeter score were analysed. Data obtained were analysed by the SPSS windows program and the results of this study were as follows : 1. There were no significant correlation between oral factors such as oral hygiene index, salivary flow rate, gingival index, degree of tongue coating and pre-treatment halimeter score. 2. Difference between pre- and post-treatment halimeter score by the three modalities were significant, but correlation between pre- and post-treatment score within group was most significant in the periodontal treatment group followed by the tongue scraping group and lowest in the $ZnCl_2$ mouth rinse group. 3. Reduction of halimeter score was significant only in subjects with relatively more tongue coating in the tongue scraping group, but in the $ZnCl_2$ mouth rinse group and in the periodontal treatment group, the modality applied to each group had same significant effects without regard to the degree of oral hygiene index or gingival index. 4. Men had more tongue coating than women, and reduction of halimeter score was significant in men, but not in women.

• Journal of Environmental Impact Assessment
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• v.19 no.1
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• pp.99-106
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• 2010

The project of Cheonggyecheon revived the 5.8 kilometer stream and it removed the cover of stream and Cheonggye elevated road. It was begin October of 2003 and completed October of 2005. The purpose of this study is to analyze the air pollution change of Cheonggyecheon area and neighboring area from before and after the project. The change of concentration is compared with an air monitoring station data and measurement data. The analyzed pollutants are $NO_2$, $PM_{10}$, heavy metal, VOC which are measured at Cheonggyecheon and neighboring area. As the results, $NO_2$ concentration shows 10 % decreases in Cheonggyecheon area and neighboring area shows 16 % decreases by Chenoggyecheon restoration, and $PM_{10}$ concentration shows 15 % decreases in Cheonggyecheon area and neighboring area shows 16 % increases. One of VOC, benzene is increased in Cheonggyecheon area compared with neighboring area but Toluene, Ethylbenzene, m+p Xylene increased in neighboring area. After the Cheonggyecheon restoration, The heavy metals are not shows the improvement, but $PM_{10}$ and $NO_2$ concentration improved more than the changes of neighboring area. These improvements of pollution due to reduction of transportation and clearing of elevated road by Cheonggyecheon restoration project.

• Journal of Korea Soil Environment Society
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• v.4 no.1
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• pp.75-83
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• 1999

The purpose of this study is to investigate the chemical characteristics of the leachate for the open(illegal) dumping waste. In this study, the open dumping waste were mixed with 0, 5, 10, 15% of bentonite in each Iysimeter as a rate of weight. The simulation was evaluated by CODcr, ${NO_3}^-$, ${SO_4}^{2-}$, $Cl^-$ and heavy metals in leachate. As a result, the mixed waste with bentonite in all Iysimeters showed the reduction of CODcr and heavy metals were hardly detected. The removal rate of ${NO_3}^-$, ${SO_4}^{2-}$, $Cl^-$ was increased with the mixing rate of bentonite.

• Journal of Korean Society for Atmospheric Environment
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• v.23 no.4
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• pp.498-506
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• 2007

To reduce the vehicular emissions of air pollutants, various traffic control programs (TCPs) have been used. In 2002, two TCPs have been implemented in Seoul and Busan, respectively. In this study, based on the study results on the effectiveness of the TCP in Seoul (Kim et al., 2005) and Busan (Lee et al., 2006), emission reduction by the TCP in Seoul was estimated and their contribution to the ambient air pollutants' concentrations was discussed. During the TCP period in 2002 at Seoul, emissions of air pollutants were reduced by 35% for CO and $NO_2$, 80% for HC, 23% for $PM_{10}$, and 24% for $SO_2$. Vehicular emission reduction affected the ambient concentrations significantly for $NO_2$. However, for $SO_2$, vehicular emission reduction did not affect the ambient concentration significantly. For $PM_{10}$, vehicular emission reduction did not affect the ambient concentration significantly if considering fugitive emissions.

• Korean journal of applied entomology
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• v.16 no.2 s.31
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• pp.79-86
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• 1977

Four experiments were carried out under farmer's field conditions to determine economic threshold levels of major rice pests aad attempt a reduction in the number of insecticide applications. In the experiments were included check treatments, insecticide schedules representing the official recommendations to farmers, and several corrective treatments. A careful record was kept of insect pest densities and disease incidence. i) In the north at Suweon and Icheon where Chilo suppresalis. (Walk.), the striped rice borer, was active in the first generation, no significant yield differences were obtained between plots receiving several insecticide applications and those left totally unprotected. The mean yields were high (5.2-7.6t/ha). ii) First generation borer activity rising to $8.6\%$ injured tillers was below the economic threshold since no yield reduction was recorded in either japonica varieties or the high-yielding Tongil variety. iii) Evidence was obtained thst berer damage was made good by replacement of infested tillers (compensatory growth), C. suppressalis populations were always low in the second generation. iv) The experimental results obtained at Suweon and Icheon do not justify the present official recommendations of 6-7 pesticide applications. v) further south at Iri a substantial yield reduction occurred due to an early outbreak of stripe disease transmitted by Laodelphax striatellus (Fallen), the small brown planthopper; a mean of 1-2 individuals/hill was recorded immediately after transplanting. C. suppressalis probably contributed to this yield reduction. vi) Several applications against the vector failed to prevent the rapid spread of stripe to the susceptible variety in the Iri experiment: in surrounding fields the resistant Tonsil varivety was ralatively unaffected. vii) Pests of lesser importance were Nephotettix cinctieps (Uhler), Nilaparvata lugens (Stil), Sogatella furcifera (Horv..), and leaf miners.

• Journal of Korean Society for Atmospheric Environment
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• v.28 no.5
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• pp.506-517
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• 2012

Electronic Toll Collection System (ETCS), so called "Hi-Pass" in Korea, has improved traffic flow at toll gate of highways. It is known that the improvement of traffic flow should reduce air pollutants and $CO_2$ from vehicles. In this study, real driving emission of a light duty truck with Portable Emission Measurement System(PEMS) has been measured to evaluate the emission reduction effect due to ETCS. The correlations between driving variables and emissions have been analyzed to verify its effect on traffic flow improvement and emission reduction at toll gate. We considered average vehicle speed, Relative Positive Acceleration (RPA), and the distance of queue as driving variables. Compared to passing Manual Toll Collection System (MTCS) lane without queue, ETCS was able to reduce 38.7% of $NO_x$, 21.6% of soot, and 27.7% of $CO_2$. The results showed that the higher the average vehicle speed, the lower RPA and no queue in ETCS contributed to the emission reductions. Linear equation models with RPA and queue have been established by the multiple linear regression method. The linear models resulted in the higher coefficient of determination than those with only average vehicle speed used for establishing vehicle emission factors.

• Journal of Korean Physical Therapy Science
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• v.5 no.2
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• pp.595-602
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• 1998

The purpose of this study was to investigate the effect of sequential intermittent pneumatic compression in patients with lymphedema who were hospitalized for three days at Samsung Medical Center. Thirty-three subjects with lymphedema was selected by physician referral. A selection of the patients was made according to the following criteria : 1) no known metastases, 2) no infection after the a difference of at least 10% in the volumes of edematous limb. All patients were treated with the Lympha-Press(Model 103-A). Circumferential limb mesurements was done before and after a 3-day treatment period. As a result of sequential intermittent pneumatic compression therapy. All extremity showed a decrease in circumferential measurements with the maximal reduction occurring at the wrist(55.75 %) for the upper extremities and at the lower 1/3 of calf (40.61%) for the lower extremities. Upper extremity arm was reduced by 42.1% and lower extremity leg by 33.61%. In contrast with this, the proximal levels of arm patients and leg showed comparatively poor reduction than distal levels. Almost 44.44% of arm patients and 5.26% of leg patients experienced significant reduction(> 50%) after compression therapy. These data clearly indicates that Sequential Intermittent Pneumatic Compression Therapy was effective treatment for reducing of extremity volume in patients with lymphedema. but this was variable degree and dependent on the amount of pre-existing lymphedema. Other factors such as duration of edema, etiology, previous history of radiology, age did not appear to influence the extend of improvement. Further sutdies will be necessary to determine long term benefit of this therapy.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.19 no.1
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• pp.44-51
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• 2005

In this paper, reduction characteristics of the AC and DC flashover voltage in the horizontal air gap of sphere-sphere electrode system were investigated when the combustion flame was present near the high voltage electrode. The voltage and current waveforms were measured, when the flashover is occurred, in order to examine the flashover polarity by flame. The reduction characteristics of AC flashover voltage were discussed with the thermal ionization process, the relative air density and the deflection phenomena in the shape of flames that caused by the coulomb's force. As the results of an experimental investigation, It was found that the reduction of flashover voltages in sphere-sphere system, in comparison with the no flame case, are $79.9[\%]$ for k=0, $82.9[\%]$ for k=0.5, $87.5[\%]$ for k=1.0, $85.0[\%]$ for h=0[cm], $40.8[\%]$ for h=5[cm] and $28.2[\%]$ for h=9[cm] when ac voltage is applied. The influence for thermal ionization process of the combustion flame in small scale no particular change is recognized.

• Journal of The Korean Society of Clinical Toxicology
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• v.17 no.2
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• pp.66-78
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• 2019

Purpose: Thallium (TI+) autometallography is often used for the imaging of neuronal metabolic activity in the rodent brain under various pathophysiologic conditions. The purpose of this study was to apply a thallium autometallographic technique to observe changes in neuronal activity in the forebrain of rats following acute carbon monoxide (CO) intoxication. Methods: In order to induce acute CO intoxication, adult Sprague-Dawley rats were exposed to 1100 ppm of CO for 40 minutes, followed by 3000 ppm of CO for 20 minutes. Animals were sacrificed at 30 minutes and 5 days after induction of acute CO intoxication for thallium autometallography. Immunohistochemical staining and toluidine blue staining were performed to observe cellular damage in the forebrain following intoxication. Results: Acute CO intoxication resulted in significant reduction of TI+ uptake in major forebrain structures, including the cortex, hippocampus, thalamus, and striatum. In the cortex and hippocampal CA1 area, marked reduction of TI+ uptake was observed in the cell bodies and dendrites of pyramidal neurons at 30 minutes following acute CO intoxication. There was also strong uptake of TI+ in astrocytes in the hippocampal CA3 area following acute CO intoxication. However, there were no significant histological findings of cell death and no reduction of NeuN (+) neuronal populations in the cortex and hippocampus at 5 days after acute CO intoxication. Conclusion: The results of this study suggest that thallium autometallography can be a new and useful technique for imaging functional changes in neural activity of the forebrain structure following mild to moderate CO intoxication.

• Journal of The Korean Society of Agricultural Engineers
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• v.57 no.4
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• pp.51-59
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• 2015

Various Best Management Practices (BMPs) have been suggested to reduce soil erosion and non point source (NPS) pollutant loads from agricultural fields. However, very little research regarding water quality improvement with No-till (NT) has been performed in Korea. Thus, effects of NT were investigated in this study. The objective of the study was to investigate the effect of NT on the surface runoff and sediment discharge in a field. Eight experimental plots of $5{\times}30m$ in size and 3 % or 8 % in slope prepared on gravelly sandy loam soil were treated with Conventional-till (CT) and NT. Runoff and NPS pollution discharge were monitored and compared the treatments. The amounts of rainfall from 13 monitored events ranged from 28.7 mm to 503.5 mm. The runoff amount was reduced by 17.6~59.2 % in 3 % NT and 29.6~53.2 % in 8 % NT. The average NPS pollution loads of the 3 % NT plots and 8 % NT plot were reduced about 45.1~89.2 % and 47.7~98.0 % compared to those of the CT plots, respectively. This research revealed that NT can reduce the NPS pollution loads substantially as well as increase the crop yield. Runoff and NPS pollution loads reduction by NT method could be contribute to improve the water quality of streams in agricultural regions.