• Journal of Wetlands Research
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• v.22 no.3
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• pp.194-199
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• 2020

Unlike in the past, the world is facing water shortages due to climate change and difficulties in simultaneously managing the risks of flooding. The Four Major Rivers project was carried out with the aim of realizing a powerful nation of water by managing water resources and fostering the water industry, and the construction period was relatively short compared to the unprecedented scale. Therefore, the prediction and analysis of how the river environment changes after the Four Major Rivers Project is insufficient. Currently, part of the construction section of the Four Major Rivers Project is caused by repeated erosion and sedimentation due to the effects of sandification caused by large dredging and flood-time reservoirs, and the head erosion of the tributaries occurs. In order to solve these problems, the riverbed maintenance work was installed, but it resulted in erosion of both sides of the river and the development of new approaches and techniques to keep the river bed stable, such as erosion and excessive sedimentation, is required. The water agent plays a role of securing a certain depth of water for the main stream by concentrating the flow so much in the center and preventing levee erosion by controlling the flow direction and flow velocity. In addition, Groyne products provide various ecological environments by forming a natural form of riverbeds by inducing local erosion and deposition in addition to the protection functions of the river bank and embankment. Therefore, after reviewing the method of determining the shape of the Groyne structure currently in use by utilizing the mobile limit flow rate and marginal reflux force, a new Critical Movement Velocity(${\bar{U}}_d$) and a new resistance coefficient formula considering the mathematical factors applicable to the actual domestic stream were developed and the measures applicable to Groyne installation were proposed.

• Clinical and Experimental Pediatrics
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• v.50 no.10
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• pp.1005-1010
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• 2007

Purpose : To determine the optimal time of high dose intravenous immune globulin (IVIG) treatment, we analysed the clinical characteristics and progress of a group of Kawasaki disease patients who had early treatment with IVIG. Method : A retrospective study was conducted of 188 patients with Kawasaki disease who were admitted to Yeungnam University Medical Center from January 2000 to December 2005. All patients were treated with a high dose IVIG and high dose aspirin for the initial acute phase treatment. The early treatment group consisted of 94 patients who received treatment before 5 days of fever, and the conventional group consisted of 94 patients who were treated on or after day 5. The patients' sex, age, laboratory findings, total duration of fever, duration of fever after initial IVIG, need for additional IVIG and coronary artery status were noted. Result : There were no significant differences between the two groups in sex ratio and age. No significant differences were noted in the level of WBC count, ESR, CRP, serum albumin, LDH, total duration of fever and coronary abnormality. But the value of ALT($151.8{\pm}17.3$ vs. $81.9{\pm}13.4$, P=0.002), duration of fever after initial IVIG ($3.8{\pm}0.5days$ vs. $2.1{\pm}0.2days$, P=0.003), and rate of additional IVIG (15.9% vs. 6.3%, P=0.037) were significantly higher in the early treatment group. There was no significant difference in initial dose of IVIG, but dosage of aspirin was lower in early treatment group (P=0.037). Conclusion : There is no evidence that early treatment of IVIG has greater efficacy in preventing cardiac sequelae than conventional treatment. In addition, early treatment is likely to result in a greater requirement for additional IVIG treatment.

• Journal of Korean Society of Forest Science
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• v.80 no.3
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• pp.279-286
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• 1991

This study was carried out to investigate relationships between atmospheric $SO_2$ concentration and both soluble sulphur contents in the tree leaves and bark pH to test the possibility of using them as bioindicators for air pollution. Mt. Kwanak, Mt. Nam, Mt. Bukhan (located in Seoul) and Mt. Paldal (located in Suwon, Kyonggi-do) as polluted areas and Pyongchang, Kwangwon-do as an unpolluted area were selected for this study. Soluble sulphur contents in the leaves and hark pH of two tree species (Pines densiflora S. et Z. and Quercus mongolica Fisch.) were analyzed in May, August, and October, 1990 by $BaSO_4$ precipitation method and pH measurement, respectively. In both species, concentration of soluble sulphur in the leaves increased with increasing concentration of atmospheric $SO_2$ (correlation coefficient : 0.52). Soluble sulphur contents in the 2-year-old needles of Pines densiflora (0.170%) and current year leaves of Quercus mongolica (0.081%) in Mt. Nam in the center of Seoul were higher than those in unpolluted Pyongchang area (0.023% and 0.034%, respectively). Bark pH decreased with increasing atmospheric $SO_2$ concentration (correlation coefficient : -0.52). Bark pH of P. densiflora (pH 3.42) and Q. mongolica (pH 3.63) in Mt. Nam were lower than those in Pyongchang area (pH 3.94 and pH 4.93, respectively). Both soluble S content in the leaves and bark pH were recognized as suitable bioindicators for air pollution by $SO_2$. Especially, bark pH showed more sensitive response to air pollution by $SO_2$ than soluble S concentration in the leaves. The lowest concentration of soluble sulphur and the highest bark pH in August were considered to be due to heavy rain during the rainy season. Soluble S content in the leaves and bark pH were not significantly different at 5% level between the two species in polluted areas.

• Journal of the Korean Applied Science and Technology
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• v.20 no.1
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• pp.33-43
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• 2003

$LiMn_2O_4$ catalyst for $CO_2$ decomposition was synthesized by oxidation method for 30 min at 600$^{\circ}C$ in an electric furnace under air condition using manganese(II) nitrate $(Mn(NO_3)_2{\cdot}6H_2O)$, Lithium nitrate ($LiNO_3$) and Urea $(CO(NH_2)_2)$. The synthesized catalyst was reduced by $H_2$ at various temperatures for 3 hr. The reduction degree of the reduced catalysts were measured using the TGA. And then $CO_2$ decomposition rate was measured using the reduced catalysts. Phase-transitions of the catalysts were observed after $CO_2$ decomposition reaction at an optimal decomposition temperature. As the result of X-ray powder diffraction analysis, the synthesized catalyst was confirmed that the catalyst has the spinel structure, and also confirmed that when it was reduced by $H_2$, the phase of $LiMn_2O_4$ catalyst was transformed into $Li_2MnO_3$ and $Li_{1-2{\delta}}Mn_{2-{\delta}}O_{4-3{\delta}-{\delta}'}$ of tetragonal spinel phase. After $CO_2$ decomposition reaction, it was confirmed that the peak of $LiMn_2O_4$ of spinel phase. The optimal reduction temperature of the catalyst with $H_2$ was confirmed to be 450$^{\circ}C$(maximum weight-increasing ratio 9.47%) in the case of $LiMn_2O_4$ through the TGA analysis. Decomposition rate(%) using the $LiMn_2O_4$ catalyst showed the 67%. The crystal structure of the synthesized $LiMn_2O_4$ observed with a scanning electron microscope(SEM) shows cubic form. After reduction, $LiMn_2O_4$ catalyst became condensed each other to form interface. It was confirmed that after $CO_2$ decomposition, crystal structure of $LiMn_2O_4$ catalyst showed that its particle grew up more than that of reduction. Phase-transition by reduction and $CO_2$ decomposition ; $Li_2MnO_3$ and $Li_{1-2{\delta}}Mn_{2-{\delta}}O_{4-3{\delta}-{\delta}'}$ of tetragonal spinel phase at the first time of $CO_2$ decomposition appear like the same as the above contents. Phase-transition at $2{\sim}5$ time ; $Li_2MnO_3$ and $Li_{1-2{\delta}}Mn_{2-{\delta}}O_{4-3{\delta}-{\delta}'}$ of tetragonal spinel phase by reduction and $LiMn_2O_4$ of spinel phase after $CO_2$ decomposition appear like the same as the first time case. The result of the TGA analysis by catalyst reduction ; The first time, weight of reduced catalyst increased by 9.47%, for 2${\sim}$5 times, weight of reduced catalyst increased by average 2.3% But, in any time, there is little difference in the decomposition ratio of $CO_2$. That is to say, at the first time, it showed 67% in $CO_2$ decomposition rate and after 5 times reaction of $CO_2$ decomposition, it showed 67% nearly the same as the first time.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.60 no.1
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• pp.63-69
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• 2015

This study was conducted to measure the effect of PE film mulching and irrigation methods on the growth, yield and antioxidant activity of potatoes tubers, in order to examine the possibility of cultivating potatoes in winter season in vinyl greenhouse on the reclaimed tidal land with weak ground inside the sea wall currently completed. The test was conducted on the sandy loam soil (Munpo series), and its salt concentration was 0.42% at the time of planting. The emergence speed per kind of PE film mulching was in the order of black > coloration > transparent > green color, with the black color showing the fastest speed. The temperature change during a day per kind of PE film mulching was in the order of transparent > coloration > green > black color. As for the salt concentration in the soil for each different way of water management, the salt concentration in the treatment of drip irrigation with 1 week interval was lower than that drip irrigation with 2 weeks interval. As for the growth of above-aerial part, plant length was higher, number of tiller and leaves were more and dry weight of above-aerial part was larger in the treatment of drip irrigaton with 1 week interval than drip irrigation with 2 weeks interval. As for the yield of potatoes depending on each way of water management, the yield in the treatment of drip irrigation with 1 week interval was more than drip irrigation with 2 weeks interval. The yield for each different kind of PE film mulching in the weekly drip-irrigation management section was in the order of transparent ${\geq}$ black ${\geq}$ coloration ${\geq}$ green color. In both of total phenol content and DPPH free radical activity experiments, the content and activity were higher with pear color vinyl treatment.

• Journal of the Society of Disaster Information
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• v.16 no.1
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• pp.163-177
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• 2020

Purpose: While it is very important to maintain facilities recently, the introduction and its application of high technology in the facility maintenance industry has increased. It is necessary for high technology to secure reliability through the verification and certification system of diagnostic equipment to have an effective impact in the field, but there is difference between the industry's perspective and realistic level of technology apart from social demand for the system of the system. This paper dealt with the introduction of a verification and certification system for rational facility diagnostic equipment with the opinion survey on managers about the current situation. Method: Survey is carried out targeting managers in the maintenance and construction regarding the necessity and urgency of introducing a verification and certification system to promote the introduction and its application of high technology of diagnostic equipment and facility inspection. Also, the introduction to a verification and certification system was reviewed for advanced facility diagnostic equipment through foreign research about similar systems and comparative analysis of similar systems related to the certification of 21 domestic equipment. Result: It showed that, regarding the application of high technology, it is necessary for most managers to introduce high technology such as drones, robots, etc., in the maintenance industry, and when high technology is introduced, it will have a considerable effect in the field. On the other hand, the current technology level in Korea is relatively low, so it turned out to take a certain amount of time for the application of technology. Also, it was found that the management of reliable facility diagnostic equipment will be possible through the introduction of the verification and certification system for facility diagnosis equipment. Meanwhile, the survey is conducted on similar systems about foreign and domestic diagnosis and measuring equipment, etc., but there is no system to verify and certify equipment applied with high technology directly to facility diagnosis maintenance. However, because Japan has a system of verifying the performance of diagnostic equipment and South Korea has 21 similar inspection and diagnostic equipment certification systems among 186 certification systems, it is considered to be possible to design systems which utilize them. Conclusion: According to the managers' opinion, it seems that the introduction of the system supporting the application of 4th industrial technology for the equipment and the use of the equipment with high reliability has sufficient validity. However, because our high technology level is undervalued compared to the urgency, the system for checking high technology facilities and certifying diagnostic equipment should be to be implemented in form of escalation considering technical use and verification level. Apart from the introduction of the verification and certification system, it is necessary for special investment, support and efforts to promote advanced facility diagnostic equipment.

• Journal of Nutrition and Health
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• v.43 no.4
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• pp.382-394
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• 2010

The purpose of this study was to evaluate the effects of a nutrition education program as part of health promoting projects in an elementary school. A total of 168 students in the 4th grade were enrolled in the program for 6 months. A self-administered questionnaire was developed to assess nutrition knowledge and dietary habit. Nutrient intakes and body shape perceptions were measured using 24-hour recall method and self-ratings of body shape figures, respectively. The education program was conducted in various ways, focused on healthy dietary behavior, nutrients' roles and sources, and proper body shape perceptions, etc. After the education program, nutrition knowledge and dietary habit were significantly improved. Dietary habit scores were significantly and positively related to nutrition knowledge levels. Body shape perceptions were significantly and properly changed after the program. Dissatisfaction with perceived current body shape and discrepancy between shapes desired and considered healthy were significantly decreased. But girls still indicated a desire to be leaner than shapes which were perceived current and considered healthy. Nutrient intakes were partly improved by the program, but some nutrients, such as calcium, folate, zinc, sodium and niacin, were still remained deficient or excessive. These findings indicate that enhancement of nutrition knowledge is extended to the improvement of dietary habit. In addition, establishment of proper body shape perception is closely related to healthy dietary habits and is required to good nutrition and health.

• The Korean Journal of Pesticide Science
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• v.16 no.3
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• pp.217-221
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• 2012

This study was carried out to evaluate residual characteristics of tolclofos-methyl in ginseng and elucidate the reason for its high detection rate from fresh ginseng selling at markets. Seeds of ginseng were sowed after seed dressing with tolclofos-methyl and after a year of growth, the young seedlings were transplanted to field. They were then harvested annually until three-years of growth and the pesticide residue was analyzed in them. LOD and LOQ of the pesticide were 0.001 and 0.003 mg/kg, respectively. Recovery test was carried out to validate the analytical method for tolclofos-methyl in ginseng. The ginseng seedlings were fortified with the test pesticide at the level of LOQ, ten times of LOQ and maximum residue concentration of tolclofos-methyl. Its recovery ranged from 77.37 to 100.16%. Residual concentration of tolclofos-methyl in ginseng seedlings just before transplanting and two-year-old ginseng were from 7.58 to 8.05 and from 6.46 to 6.79 mg/kg, respectively. In case of three-year-old ginseng, it was found to be from 4.18 to 4.35 mg/kg. As a result of annual pesticide residue analysis, concentration of the pesticide was found to decrease time-coursely in ginseng. This may be due to decomposition and increasing of fresh weight of the ginseng during the cultivation periods of three years.

• The Journal of Engineering Geology
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• v.23 no.3
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• pp.201-216
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• 2013

Ground penetrating radar (GPR) surveys were conducted in a sand tank model in a laboratory and at an alluvial field site to detect the groundwater table and to investigate the influence of saturation on GPR response in the unsaturated zone. In the sand tank model, the groundwater table and saturation in the sand layer were altered by injecting water, which was then drained by a valve inserted into the bottom of the tank. GPR vertical reflection profile (VRP) data were obtained in the sand tank model for rising and lowering of the groundwater table to estimate the groundwater table and saturation. Results of the lab-scale model provide information on the sensitivity of GPR signals to changes in the water content and in the groundwater table. GPR wave velocities in the vadose zone are controlled mainly by variations in water content (increased travel time is interpreted as an increase in saturation). At the field site, VRP data were collected to a depth of 220 m to estimate the groundwater table at an alluvial site near the Nakdong river at Iryong-ri, Haman-gun, South Korea. Results of the field survey indicate that under saturated conditions, the first reflector of the GPR is indicative of the capillary fringe and not the actual groundwater table. To measure the groundwater table more accurately, we performed a GPR survey using the common mid-point (CMP) method in the vicinity of well-3, and sunk a well to check the groundwater table. The resultant CMP data revealed reflective events from the capillary fringe and groundwater table showing hyperbolic patterns. The normal moveout correction was applied to evaluate the velocity of the GPR, which improved the accuracy of saturation and groundwater table information at depth. The GPR results show that the saturation information, including the groundwater table, is useful in assessing the hydrogeologic properties of the vadose zone in the field.

• Journal of Science of Art and Design
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• v.8
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• pp.63-94
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• 2005

ChangSayng-Do in the late Chosun dynasty was a kind of traditional painting which sublimated the philosophy and emotion of everyday life into an aesthetic consciousness through a long history of Korean people . It would represent a human wish and desire to live a long and healthy life, which was implicated by way of Taoism. The major themes of ChangSayng-Do - mountains, the sun, cloud, water, rock, deer, tortoises, cranes, pine trees, bamboos, peaches, and herbs of eternal youth - were all symbols used. to wish for a long-life and immortality in real world. All or some of these items were represented in paintings, which resulted in the various kinds of ChangSayng-Do. The main concern of this thesis will be centered around the naturalistic subjects shown in ChangSayng-Do. This thesis consists of four chapters. The first chapter describes the purpose of and need for the research, and its method and scope. The second chapter deals with the origin and style of ChangSayng-Do, and the background of its formation. It is found out that the formative characteristic of ChangSayng-Do lies in the archetype, the unity of man and nature following the traditional view of nature. It is also found out that ChangSayng-Do implied the notions of Supernatural Being, Yin-Yang and Five Elements, Taoism, and Confucianism as well as Korean shamanism. Third chapter is largely about an analytic investigation into symbolic visualization of ChangSayng-Do. Firstly, the subject matters shown in ChangSayng-Do consist of items of wishful omen for long-life and good luck, and any motif in a picture implies a symbolism of eternal youth and long-life. Secondly, the view of colors shown in ChangSayng-Do is closely connected to Five Elements and Five Direction, a traditional oriental philosophy of universe, and these symbolic colors are based on shamanism and Yin/Yang-Five Elements. According to an iconological analysis, it is confirmed that these viewpoints are consistent with formative principles and expressive methods of ChangSayng-Do to some extent. The fourth chapter is one of the most important elements for visualization of ChangSayng-Do. The symbolic meaning of long life and good luck is the major source of its popularity inside the palace as well as among the people in general. The fact that ChangSayng-Do was used to ornament the palace was documented in $\lceil$UiGuey(documents about Chosun dynasty$\rfloor$. Also during the late period of Chosun dynasty, the appreciators of arts had begun to spread from high level class to lower level class, and many pictures represented in $\lceil$Hanyang-Ga$\rfloor$ were the ones produced and circulated for those increased consumers. As for the folk-artistic characteristics, the anonymity and arbitrary naturalness of ChangSayng-Do demonstrates that the folk-artistic elements were fully soaked into the life styles of people in general. ChangSayng-Do further shows that a human being is located in the center of the universe, and that all the natural phenomena and ecology are observed to happen around human beings, and that the results of those happenings are connected to man's course of life. It is discovered that the subject matters of ChangSayng-Do in the late Chosun dynasty imply another idea inside metaphors and symbols. With regard to the arrangement of time and space, the unity or oneness of oneself with the world is more highly regarded than one's individual subjectivity: there exist multiple times and spaces in a single picture This reveals a wholistic view of oneness which does not permit the division between phenomenon and substance. To conclude, this thesis inquired into ChangSayng-Do in the late Chosun dynasty focusing on the expression of archetype-symbols. And through the analysis and demonstration, this thesis re-established constructional principles and formative characteristics of ChangSayng-Do and then settled a new phase of ChangSayng-Do, with a deep under-standing of fundamental thoughts of Korean people underlying ChangSayng-Do.