• Journal of the Korean earth science society
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• v.39 no.2
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• pp.178-192
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• 2018

The purposes of this study were to develop and apply on learning on geological field trip utilizing the social construction of scientific model. We developed field trip places by considering not only Orion (1993)'s novelty space but also the achievement standards of 2015 national curriculum. The subjects of the study were 8 in the 'G' science gifted education center. We conducted a study using the theme of 'How was formed Mt. Gwanak?' on 5 lessons including a series of 2 field trip lessons and 3 lessons utilizing the social construction of scientific model. Students participated in pre- and post-test on the understanding of scientific knowledge about formation of mountain. Semi-structured interview was used to analyze students' learning about geological field trip in terms of affective domain. Results were as follows. First, there were 2 places of upper-stream valley and down-stream valley separately. They contained outcrops gneiss, granite, joint in the valley, xenolith, fault plane, mineral in the valley. Second, pre- and post-test and semi-structure interview were analyzed in terms of what scientific knowledge students learned about and how Mt. Gwanak was formed. Seven students explained that Mt. Gwanak was volcano during pretest. Seven students described how granite was formed to form Mt. Gwanak. They also understood geological time scale, i.e., metamorphic rock. Third, the geological field trip was effective to low achievement geoscience students as they engaged in the activities of field trip. Using positive responses on affective learning was effective on learning on geological field trip when utilizing the social construction of scientific model. This study suggests that teachers use an example 'model' on geoscience education. This study also suggests that teachers apply the social construction of scientific model to geological field trip.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.5
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• pp.867-879
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• 2016

Since the 1970s, the region of its own pedestrian center and environmental pollution caused by exhaust gases have been reduced gradually in a continuous increase of the vehicle, school route the central business district, around the school, the sidewalk where the vehicle do not pass, facilities of minimum for the safety of pedestrians and systematic management of an area where an unspecified number and alleys impassable is insufficient. Recently, in response to the "Law for convenience enhancing safety and walking" is enforced in Korea, research on Pedestrian only Street has been actively about the government, the standard for calculating the weights of evaluation associated with it. it is a actuality, however, there are insufficient, evaluation for business promotion is being conducted evaluation polite manner by using, for example, scale residence time and purpose of the passengers as there is no car that has been carried out on a voluntary basis through the municipality have. In this study, by suggesting a method for the selection of the street without a car, make a survey by placing a purpose in the selection method presentation of the street with no car to be construction future, was researching. F.G.I (Focus Group Interview) survey, professors, staff in urban, traffic field of experts in order to present the weights for the evaluation of the Pedestrian only Street by using the evaluation index by type of Pedestrian only Street, was interviewed about the evaluation index for the conducted for professionals engaged in the engineering company, and randomly selected 200 peoples, weighted evaluation of the street with Pedestrian only Street was proposed. By classifying the items purpose and goals of the evaluation type by this by applying the weight, and present the weight of the detailed indicators each corresponding to each item, and scored on the basis of the result, in this paper it can be so that one methodology for the selection standard for the construction as Pedestrian only Street, and the weight of the evaluation of the type that has been derived, the selection and evaluation methods and then added to these criteria to settle careful study of the reference should be performed further.

• 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.

• Journal of Animal Science and Technology
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• v.53 no.1
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• pp.59-66
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• 2011

For the improvement of productivity of beekeepers and to develop new management strategy through the analysis of current honeybee-keeping management types and evaluation of related skills and basis in Korea were surveyed. The serial surveys were carried out in 2008 for a total of 253 beekeepers from different localities in Korea. The results revealed that 145.9 colonies of honeybee were managed by each beekeeper in Korea. The beekeepers group who were younger than 55 years possessed 191.7 colonies. The older age group of beekeepers kept rather smaller number of colonies. The career groups over 15 years in apiculture were keeping 176.0 colonies in average. The numbers of bee colonies were not significantly different among localities and educational backgrounds. The migratory apiaries with 145.9 hives were dominant than those fixed ones with 83.0 (p<0.01). It was observed that 57.8% of apiaries were located in the vicinity of farmer's house, whereas 30.3% were managed in mountain area; however older group (65.4%) preferred to keep it near their houses (p<0.05). The proportion (35.7%) of part-time fixed apiary was the highest among four apiary management types. The younger group and high career group operated full-time migratory apiary (38.8% and 40.3%) (p<0.05), respectively. However, the older group and low career group preferred as part-time fixed one (43.2% and 46.6%), respectively (p<0.001). There was no significant difference among localities. The surveyed beekeepers produced propolis, commercial colonies, pollen, royal jelly, and pollination hives in addition to honey. The group of less than 15 years career and mountain apiary mainly produced propolis and pollen. However, those who dwell in small and middle areas mainly produced propolis and commercial colonies. The levels related to beekeeping skills and basis were evaluated as intermediate from 3.11 and 2.86 points on 5 points scale, respectively. More careered group having skill level of 3.33 point and basis level of 3.02 showed higher levels than less careered one. The levels of skill and basis evaluated from age groups and localities were similar with each other with no significance.

• Journal of Dental Rehabilitation and Applied Science
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• v.34 no.4
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• pp.270-279
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• 2018

Purpose: The aim of this study was to assess the patients' perception, acceptance, and preference of the difference between a conventional impression and digital impression through questionnaire survey. Materials and Methods: Thirteen (6 male, 7 female) subjects who experienced both digital and conventional impression at the same day were enrolled in this study. Conventional impression were taken with polyvinylsiloxane and digital impression were performed using a newly developed intra-oral scanner. Immediately after the two impressions were made, a survey was conducted with the standardized questionnaires consisting of the following three categories; 1) general dental treatment 2) satisfaction of conventional impression 3) satisfaction of digital impression. The perceived source of satisfaction was evaluated using Likert scale. The distribution of the answers was assessed by percentages and statistical analyses were performed with the paired t-test, and P < 0.05 was considered significant. Results: There were significant differences of the overall satisfaction between two impression methods (P < 0.05). Digital impression showed high satisfaction in less shortness of breath and odor to participants compared to conventional impression. The use of an oral scanner resulted in a discomfort of TMJ due to prolonged mouth opening and in lower score of the scanner tip size. Conclusion: It was confirmed that the preference for the digital impression using intraoral scanner is higher than the conventional impression. Most survey participants said they would recommend the digital impression to others and said they preferred it for future prosthetic treatment.

• Plant Journal
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• v.18 no.4
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• pp.58-65
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• 2023

In this study, to increase the methane content of biogas supplied from Nanji Water Regeneration Center and to purify impurities, a three-stage membrane purification process was designed and installed to demonstrate operation. The methane concentration of biomethane produced in the 2 Nm3/h purification process was set to three cases: 95%, 96.5%, and 98%, and the membrane area ratio of the membrane was 1:1, 1:2, 1:1:1, The optimum conditions for the membrane area of the separator were derived by changing to five of 1:2:1 and 1:2:2. 3 stage separation membrane process of 30 Nm3/h was installed to reflect the optimum condition of 2 Nm3/h, and biomethane production of 98% or more of methane concentration was demonstrated. As a result of the operation of the 2 Nm³/h refining device, the methane recovery rate at the 98% methane concentration was 95.6% when the membrane area ratio was 1:1 as the result of the two-stage operation of the separator, and the recovery rate of methane at 1:2 was increased to 96.8%. The methane recovery rate of the membrane three-stage operation was highest at 96.8% when the membrane area ratio was operated at 1:2:1. The carbon dioxide removal rate was 16.4 to 96.4% and the 2:2 to 95.7% film area ratio in the two-step process. In the three-step process, the film area ratio was 1:2:1 to 95.4%, and the two-step process showed higher results than the three-step process. In the 30 Nm3/h scale biogas purification demonstration operation, the methane concentration after purification was 98%, the recovery rate of methane was 97.1%, the removal rate of carbon dioxide was 95.7%, and hydrogen sulfide, the cause of corrosion, was not detected, and the membrane area ratio was 1:2:1 demonstration operation, biomethane production with a methane concentration of 98% or higher was possible.

• Journal of Chest Surgery
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• v.38 no.5 s.250
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• pp.357-365
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• 2005

Background: Patients with mitral regurgitation (MR) in the setting of coronary artery disease have a dismal long-term prognosis whether treated medically or surgically. Moreover, the optimal management of moderate ischemic MR at the time of coronary artery bypass grafting (CABG) remains the subjects of controversy. Thus, the present retrospective study was undertaken to determine whether mitral valve surgery for moderate ischemic MR at the time of CABG would be preferable to CABG alone in terms of clinical outcome. Material and Method: Between January 1997 and December 2003, 34 patients with moderate (Gr 3/4) ischemic MR underwent CABG alone (Group I, n=23) or CABG plus mitral valve surgery (Group II, n=11). Operative mortality, long-term survival and echocardiographic parameters were used to evaluate the efficacy of mitral valve surgery in patients with moderate ischemic MR. The mean follow-up durations of each group were $69.3\pm4.3$ months and $53.1\pm4.9$ months respectively. Result: There was no hospital mortality in both groups. There was one case of late mortality in Group I. The mean number of bypass graft was similar ($3.8\pm1.2\;vs\;3.7\pm1.3$ respectively). Cardiopulmonary bypass time was longer in group II (p=0.014). In group II, all of the patients received mitral annuloplasty using ring. On immediate postoperative echo-cardiogram, mitral regurgitation was reduced more in group II (p=0.002). Echocardiogram performed at last follow-up state showed no difference except the grade of MR between the two groups. Actuarial survival of both groups at 5 years was similar ($95.5\%\;vs\;100\%$, p=0.48). Conclusion: This study shows that in selected patients with moderate ischemic MR, CABG without mitral valve surgery might be sufficient. However, patients with low EF and NYHA functional class pre-operatively had tendency of significant residual MR, so mitral valve surgery should be necessary in these patients, and moreover, MR severity and left ventricle volume decreased more in mitral valve surgery group. Therefore, more large-scale studies are necessary to determine these effects on the ventricular function and long-term survival.

• Microbiology and Biotechnology Letters
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• v.39 no.1
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• pp.56-62
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• 2011

We investigated quality characteristics of Seoktanju (one of the Korean traditional rice wine) which was fermented using five kinds of Korean commercial Nuruks. The purpose of this study was to research what effects on the quality of Seoktanju by using different Nuruks. We analyzed general component such as each mash's temperature change patterns, pH, titrable acidities, reducing sugar contents, volatile acids, and sugar contents during fermentation periods and studied sensory evaluation of produced Seoktanju (10 days). On the whole, temperature change patterns in the each mashes were depend on room temperature. All Seoktanju's pH was reduced rapidly up to three days after first mashing (pH 3.13-3.57) and after that was increased gradually. The end of fermentation pH was pH 3.6-4.05. Mostly, acidities were indicated high(0.59%) and Nuruk-B was showed highest acid value. These results seems to be different as occasion organic acids producing activity depend on the number of yeast, material contents, optimal temperature in the each mashes by fungi and lactic acid bacteria in Nuruks. In reducing sugar contents and sugar contents, Nuruk-C treatment were showed the highest value with 5.36%, $23^{\circ}brix$, respectively and alcohol content was lowest with 8.6%. In the five kinds of reproduced Seoktanju, alcohol content was the highest in the treated Nuruk-A group. Volatile acid value was the highest with 132.6~263.7 ppm at the 3 day after first mashing day but as the fermentation time goes on, it was reduced sharply by 5.25~5.94 ppm. Sensory evaluation was performed with 5 point scale, the Seoktanju using Nuruk-D was presented by 4 point, while Nuruk-A was presented lowest by 2.77 point on overall acceptability.

• Proceedings of the Korean Environmental Health Society Conference
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• 2003.06a
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• pp.24-25
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• 2003

Lead is ubiquitous in the human environment as a result of industrialization. China's rapid industrialization and traffic growth have increased the potential for lead emissions. Lead poisoning in children is one of the most common public health problems today, and it is entirely preventable. Children are more vulnerable to lead pollution and lead in their bodies can affect their nervous, circulatory, and digestive systems. Children are exposed to lead from different sources (such as paint, gasoline, and solder) and through different pathways (such as air, food, water, dust, and soil). Although all children are exposed to some lead from food, air, dust, and soil, some children are exposed to high dose sources of lead. Significant sources of lead for China's children include industrial emissions (often close to housing and schools), leaded gasoline, and occupational exposure that occurs when parents wear lead-contaminated clothing home from work, burning of coal for home heat and cooking, contaminated food, and some traditional medicines. To assess the blood lead level in children in China, a large-scale study was conducted in 19 cities among 9 provinces during 1997 to 2000. There were 6502 children, aged 3-5 years, were recruited in the study The result indicates that the mean blood lead level was 8.83ug/dl 3-5 year old living in city area. The mean blood lead level of boys was higher than that of girls (9.1l ug/dl vs 8.73ug/dl). Almost 30 percent childrens blood lead level exceeded 10ug/dl. The average blood lead level was higher than that of in 1985 (8.83ug/dl vs 8.lug/dl). An epidemiological study was carried on the children living around the cottage industries recycling the lead from battery. Nine hundreds fifty nine children, aged 5-12 years, living in lead polluted villages where the lead smelters located near the residential area and 207 control children live in unpolluted area were recruited in the study. The lead levels in air, soil, drinking water and crops were measured. The blood lead and ZnPP level were tested for all subjects. The results show that the local environment was polluted. The lead levels both in the air and crops were much higher than that of in control area. In the polluted area, the average blood level was 49.6ug/dl (rang 19.5-89.3ug/dl). Whereas, in the unpolluted area, the average blood level was 12.4ug/dl (rang 4.6-24.8ug/dl). This study indicates that in some countryside area, some cottage industries induce seriously lead pollution and cause children health problem. For the introducing of unleaded gasoline in some large cities, such as Beijing and Shanghai, the blood lead level showed a declined trend since 1997. By 2000, the use of leaded gasoline in motor vehicles has been prohibited in China. The most recent data available show that levels of lead in blood among children in Shanghai decreased from 8.3ug/dl in 1997 to 7.6ug/dl in 1999. The prevalence rate of children lead poisoning (blood lead >10ug/dl) was also decreased from 37.8% to 24.8%. In children living in downtown area, the blood lead level reduced dramatically. To explore the relationship between gene polymorphisms and individual susceptibility of lead poisoning, a molecular epidemiological study was conducted among children living in lead polluted environment. The result showed that the subjects with ALAD2 allele has higher ZPP level, and the subjects with VDR B allele has larger head circumference than only with b allele. In the present study, we demonstrated that ALAD genotypes modify lead effects on heme metabolism and VDR gene variants influence the skull development in highly exposed children. The polymorphism of ALAD and VDR genes might be the molecular inherited factor modifying the susceptibility of lead poisoning. Recently, Chinese government pays more attention to lead pollution and lead poisoning in children problem. The leaded gasoline was prohibited used in motor vehicles since 2000. The government has decided to have a clampdown on the high-polluted lead smelters for recycling the lead from battery in countryside. It is hopeful that the risk of lead poisoning in children will be decreased in the further

• Journal of Embryo Transfer
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• v.22 no.1
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• pp.63-67
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• 2007

This study was performed to evaluate the efficacy of sodium carboxymethylcellulose (SCMC) for the prevention of postoperative uterus and ovary adhesion formation in the Korean black goats. Twenty adult female Korean black goats randomly were divided into five groups with four animals in each group. After the routine laparotomy, catheter for injection was inserted into the abdomen. Before abdominal closure, saline, 1% SCMC, 2% SCMC or 0.4% HA solution (50ml/10kg of body weight/head) were injected in the abdominal cavity in each group. Three weeks after surgery, second laparotomy was performed and the adhesions were scored on a scale of 0 to 10 according to their vascularity and adhesion size in uterus and ovary. This trial was repeated the four times with the interval of three weeks. In the first and second trial, the group treated with 2% SCMC significantly reduced the adhesion formation than other treatment groups (P<0.05). In the third trial, the adhesion formation was significantly reduced in 2% SCMC and 1% SCMC (P<0.05). In the fourth trial, 2% SCMC reduced the adhesion formation. However, there was no significant difference among other groups. This study showed that the 2% SCMC administered at the end of the surgery reduced the adhesion formation in the Korean black goats.