• Journal of Korean Society of Coastal and Ocean Engineers
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• v.20 no.5
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• pp.452-460
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• 2008

Anti-foaming agents and foam fences have been used to remove the foam at the outfall of power plants, but there are some problems as consumption of maintenance costs and insufficiency of effect. Therefore, development of the methods how to remove the foam by stable coastal structure has been required. In this study, numerical simulation of air entrainment was carried out to design the submerged outlet structure for reducing foam using curtain walls. The air entrainment rate and the discharge of entrained air change according to the shape of weir and curtain wall. Hence, it is necessary to design the optimum section through comparison of each case. The optimum section which has the maximum rate of foam reduction was determined by the simulation results. In addition, it was found that the flow velocity at the submerged outlet is to be smaller than 1 m/s and the submerged depth of curtain wall is to be taller than height of the submerged outlet section.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.3
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• pp.208-212
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• 1993

Since ramie suckers distribute soil surface layer within 10cm depth, some of them are dead from low soil temperature in winter. An experiment was conducted to investigate the effects of various mulching methods on safe overwintering of sucker at three or four years old, fully-grown ramie plots. The sprouting dates of ramie was March 28 in transparent vinyl mulching(TPEF), April 1 in transparent vinyl mulching over cover of straw, manure or rice hull at the amount of 500kg /10a (CM), and April 6 in black vinyl mulching(BDEF). These treatments showed earlier sprouting date from 9 to 18 days than the conventional mulching with 1000 kg straw /10a the sprouting date of which was April 15. TPEF treatment showed the earliest but ununiform sprouting. In contrast, sprouts in CM treatment was uniform but emerged somewhat later compared with the treatment of TPEF. The number of stems per unit area increased 50 percent more in TPEF, and 35 to 39 percent more in CM than the treatment of conventional mulching.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.6
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• pp.483-488
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• 1993

This study was conducted to obtain the basic information for easily judgement to level of salinity stress of the reclaimed land. Rice varieties used were Nakdongbyeo and Chilsungbyeo. In seedling stage, 13 day-old seedlings were subjected to salt solution (0, 30, 60, 90mM) for 8 days. In reproductive stage, 30 day-old seedlings were transplanted 3 hills(3 seedlings /hill) per plastic pot (diameter 28${\times}$depth 30cm). Salinity stress was given by immersing pot in the salt solution(sea water) with 4 concentrations(0, 30, 60, 90mM)for 8 days at booting stage. The stomatal resistance was increased with salinity concentrations. Salinity stress appeared to be more sensitive in seedling stage than in reproductive stage in each concentrations. The photosynthesis was decreased in salinity treatment. Salt-treated periods influenced unfavorably stomatal resistance in each stages. The leaf chlorophyll content was remarkably decreased by increasing salt concentrations. The absorption of Na+ and Cl￣ were increased as salt concentration in the culturing medium became higher, but there was no appearent difference in the absorption of K+, Mg++, and Ca++. The plant height and root length were decreased in salinity treatment. The inhibitory effect of salinity stress on root growth was more severe than in shoot growth. The stomatal resistance could have been used as bio-information.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.2
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• pp.150-156
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• 2001

To explore the feasibility of recycled paper mulching in spring-grown potato the changes of soil environments and the growth and yield of potato under non-mulched control and three mulching treatments of recycled paper (RPM), transparent polyethylene film (TPFM), and black polyethylene film (BPFM) were examined over two spring seasons in 1998 and 1999 at Suwon, Korea. The mulching materials were a recycled mulch paper with 110 g/$m^2$ and a thickness of 0.1mm, which was manufactured from old corrugated containers for this experiment and the commercial polyethylene films with a thickness of 0.01mm. RPM lowered the average soil temperature at 5-cm depth during the potato growing period by 03$^{\circ}C$ compared with the control, whereas TPFM and BPFM raised it by 2.$0^{\circ}C$, and 1.8$^{\circ}C$, respectively. On a sunny day during sprout emergence, RPM reduced the maximum soil temperature by about 5$^{\circ}C$, while TPFM and BPFM enhanced it by about 11$^{\circ}C$ and 6.$0^{\circ}C$, respectively. The temperature difference between the control and the mulching treatments decreased with the development of canopy. All the mulching treatments had an advantage in preserving the soil moisture over the control. RPM and BPFM resulted in the effective control of weed by obstructing light transmission onto soil surface, but TPFM had no control effect of weed. Sprout emergence started two to three days earlier in TPFM and BPFM, but one day later in RPM than in the control due to the altered soil temperature by the mulching treatments. However, the final percentage of emergence was notably lower in TPFM than that in the control because of too high soil temperature during daytime, but was not different among the control, RPM, and BPFM. During the early stage of potato growth, the shoot and root growth under RPM was lower compared with the control, but afterwards, RPM outpaced the control. In 1998 experiment, the tuber yield under RPM and BPFM were significantly higher than those of the control and TPFM. In 1999 experiment, there was no significant difference in tuber yield between RPM and the control.

• Economic and Environmental Geology
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• v.33 no.2
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• pp.91-100
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• 2000

It has been more than ten years since Dukun mine was abandoned. Tailings of waste deposits and slime dumps in the abandoned Dukum mine have been left to be deserted for fifty years. The results of fifty years of neglecting are nothing short of major environmental problems. Slime dumps have been exposed to air and water in the mine over ten years and then soil profile has been formed well. Soil in the upper layer (A horizon) is the light gray color due to the leaching of cations. Soil in the lower layer (A2 horizon, 0.2∼0.3m)is tinted with reddish brown and yellowish brown color due to the development of iron oxides and iron hydroxides. Soil in the lower part of B horizon of (1.0∼3.0m) with the growth of copper and zinc oxides exposes to the bluish green, light blue, and dark gray. Ranging from 3m to 8m in depth, 85 samples were taken from 22 sampling sites with 50m intervals located on the slime dump area with hand auger and trench (open cut). As tailings was distributed, heavy metal elements extracted by the process of surface water and ground water move and disperse in to the hydrosphere. Waste dumps were distributed in and around the mine and water draining from those dumps be a potential source of contamination. Soils, thus, can be dispersed into downslope and downstream through wind and water by clastic movement. These materials may be deposited in another horizon if the water is withdrawn, or if the materials are precipitated as a result of differences in pH, or other conditions in deeper horizons. These were primarily associated with acid mine drainage. The characteristics and rate of release of acid mine drainage are influenced by various chemical and biological reactions at the source of acid generations. Prolonged extration of heavy metal elements has a detrimental effect on the agricultural land and residental area. Twenty soil samples were collected from the agricultural land in the area (0∼30 cm). Seventeen samples were also taken from the sediment in the stream running alongside the dumps. The dispersion patterns of heavy metal elements are as follows: The content of As ranged 2∼6 ppm in a horizon, 20∼125 ppm in B horizon with large amount of clay mineral is concentrated and the content of Cd ranged 1∼2 ppm in A horizon, 4∼22 ppm in B horizon. Like Cd, the content of As, Cu, Zn, Pb in B horizon is higher than that in A horizon (approximately 5∼100 times). When soil formation proceeds in stages, it is necessary to investicate the B horizon with the concentration of heavy metal and preventive measures will have to established.

• Cartoon and Animation Studies
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• s.27
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• pp.177-198
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• 2012

Development of digital media and interest in education bring big progress at digital device of education globally. UK which is advanced country of education is using digital education devices such as digital chalkboards, digital desks etc. and Japan plan digital text book's through the state. At 2011, Korea which is advanced country of internet adopted digital text book 2007 with mathematics, through science and English digital text book through the state. Korea's digital textbook is in a transition period, that needs case-study of advanced country of education for setting design guide and educational effect to Digital text book plan. All researches are based on LG europe design center at London, UK and target countries are UK and Sweden which is advanced country of education and a welfare state. Analysis by using FGI, KJ, survey of questionnaire, heuristic method, concentration observation. Through analytical researches prefer using digital text book with paper text book to using solo that can offer each advantage to user and teacher. Especially Interactive GUI design of digital text book to easy to access for teacher whom not friendly with digital device. When plan Digital text book content and design needs methodical design guide for target who students and teachers an in-depth study of the appraisal and method. The results of the research are introduce the design plan as a basic research and giving useful design plan to make digital text book and digital educational media in industrial aspect.

• Journal of the Korean Society of Earth Science Education
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• v.7 no.3
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• pp.338-346
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• 2014

In this study, find out of recognition of the effect of science, society and ethical aspects on natural disasters and understanding degree of knowledge applying for SSI class aimed at elementary pre-service teachers by developing SSI training program of the 'Earth and Space' field. Also, after SSI class application we examined the change perceptions of elementary pre-service teachers. SSI training program was that elementary pre-service teachers participated in the SSI class of a variety of subjects in the field of 'Earth and Space' and directly joined in the decision-making process and reflectional discussion with colleagues as conducted in this class reflective discussion with the pre-primary teachers pre-service teachers. Elementary pre-service teachers were understanding of the nature of the science and to understand in more depth about the SSI class characteristics. This study, second grade 115 people who was taking 'science and teaching materials' course in B National University of Education at B city participated. In order to apply for SSI class, one semester based on 15 weeks until seven weeks were science and teaching materials and based on the nature of science, after 8 weeks we set the theme of the contents related to the Earth and space and give lesson applied for SSI. During 8 weeks, test subjects 4 classes were taking 50 minutes a week 100 minutes. First time has theoretical lessons in topics related to the 'Earth and space' and on the second week, each classes participate in the decision-making processes respectivly by dicussing and debating on the first week's topic as regarding social and moral aspects of it. We obtained the following results. First, elementary pre-service teachers were acquiring the results of 67% in the knowledge aspects of the 'Earth and space'. This result was determined that most of the elementary pre-service teachers were liberal arts in high school. Second, while participating in the SSI class, elementary pre-service teachers were concretely aware of the nature of SSI and the characteristics of the class. Third, the elementary pre-service teacher are thaught that introduction education courses about 'Earth and space' are needed but most of the students responded that this would require a lot of effort of teachers. This was derived from not familiar class form that did not fulfill in the science teaching methods until now.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.2
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• pp.250-256
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• 2016

The objective of this study was to investigate the effects of graded levels of isomaltooligosaccharides (IMO) on the performance, immune function and intestinal microflora and intestinal mucosal morphology of weaned pigs. In a 28-day experiment, one hundred eighty, twenty eight-day-old, crossbred (Duroc${\times}$Large White${\times}$Landrace), weaned pigs, with an initial body weight of $8.19{\pm}1.45kg$, were fed either an unsupplemented corn-soybean meal based diet or similar diets supplemented with 0.2%, 0.4%, 0.6%, or 0.8% IMO added at the expense of corn. Each treatment was replicated six times with six pigs (three barrows and three gilts) per pen. From day 0 to 14, weight gain was linearly increased (p<0.05), while gain:feed (p<0.05) was linearly improved and diarrhea rate (p = 0.05) linearly declined as the IMO level increased. On d 14, the level of the immunoglobulins IgA, IgM, and IgG in the serum of pigs were linearly increased (p<0.05) with increasing IMO supplementation. Interleukin-6 (IL-6) was linearly (p<0.05) and quadratically (p<0.05) decreased as IMO intake increased. From day 15 to 28, there was a trend for weight gain to be linearly increased, and IL-2 was linearly (p<0.05) increased as IMO supplementation increased on d 28. Over the entire experiment, weight gain was linearly increased (p<0.05), while gain:feed (p<0.05) was linearly improved and diarrhea rate (p<0.05) was linearly decreased as the IMO level increased. Supplementation with IMO had no effect on the intestinal microflora of pigs in the ileum and cecum of pigs, as well as the villus height and crypt depth in the ileum and jejunum (p>0.05). These results indicate that dietary inclusion of IMO increases weight gain, gain:feed and enhanced the immune status of pigs, and could be a valuable feed additive for use in weaned pigs, particularly during the period immediately after weaning.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.9
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• pp.918-924
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• 2008

This research investigates the influences of the presence of aquatic macrophytes on the changes of biogeochemistry in the sediments through the comparative analysis of porewater and sediments. From the in situ measurements, elevated SO$_4{^{2-}}$ concentrations were observed in the rhizosphere during the growing season, which was resulted from the oxidation of reduced sulfide in the sediments by the oxygen release from the plant roots. There was sufficient AVS in the sediments to induce observed SO$_4{^{2-}}$ concentrations. The amount of oxygen in the oxidation of AVS to produce observed SO$_4{^{2-}}$ concentrations is 0.85 g/m$^2$ day which is relevant to the results of other researches. The AVS concentrations in the vegetated sediments increased with the depth whereas there is higher mass of AVS in the surface of the non-vegetated sediments. This shows that evapotranspiration induces the transportation of SO$_4{^{2-}}$ in the surface water into the anaerobic sediments. In addition, the elevated organic content caused by the presence of plants increased $\beta$-glucosidase activities which play an important role in the carbon cycle of the sediments.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.5
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• pp.275-284
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• 2018

This study was a descriptive study to investigate the effects of nursing students' consciousness of biomedical ethics, good death recognition, and self-esteem on attitudes toward withdrawal of life-sustaining treatment. The subjects of this study were 204 nursing students attending university. The data were collected from October 24 to October 31, 2017 and analyzed using the SPSS Win. 22.0 program. Attitudes toward withdrawal of life-sustaining treatment scored $2.97{\pm}0.29$ out of 4, $3.01{\pm}0.31$ for biomedical ethics, $3.24{\pm}0.38$ for good death recognition and $3.23{\pm}0.41$ for self-esteem. There was a significant positive correlation between attitudes toward withdrawal of life-sustaining treatment and good death recognition, and there was a significant positive correlation between attitudes toward withdrawal of life-sustaining treatment and self-esteem. As a result of multiple regression analysis, it was found that good death perception affected nursing students' attitudes toward the withdrawal of life-sustaining treatment. In other words, elevated perception of good death was associated with more positives attitudes toward withdrawal of life-sustaining treatment. Based on the above results, it is necessary to develop a systematic education program for nursing college students. In addition, this researcher proposes an in-depth study to explore the variables that influence nursing students' attitudes toward withdrawal of life-sustaining treatment.