• Magazine of the Korean Society of Agricultural Engineers
• /
• v.43 no.5
• /
• pp.116-123
• /
• 2001

This paper represents results of an effort to seismically rehabilitate a 12-story nonductile reinforced concrete frame building. The frame located in the most severe seismic area, zone 4, is assumed to be designed and detailed for gravity load requirements only. Both pushover and nonlinear time-history analyses are carried out to determine strength, deformation capacity and the vulnerability of the building. The analysis indicates a drift concentration at the $1^{st}$ floor level due to inadequate strength and ductility capacity of the ground floor columns. The capacity curve of the structure, when superimposed on the average demand response spectrum for the ensemble of scaled earthquakes indicates that the structure is extremely weak and requires a major retrofit. The retrofit of the building is attempted using viscoelastic (VE) dampers. The dampers at each floor level are sized in order to reduce the elastic story drift ratios to within 1%. It is found that this requires substantially large dampers that are not practically feasible. With practical size dampers, the analyses of the viscoelastically damped building indicates that the damper sizes provided are not sufficient enough to remove the biased response and drift concentration of the building. The results indicate that VE-dampers alone are not sufficient to rehabilitate such a concrete frame. Concrete buildings, in general, being stiffer require larger dampers. The second rehabilitation strategy uses concrete shearwalls. Shearwalls increased stiffness and strength of the building, which resulted in reducing the drift significantly. The effectiveness of VE-dampers in conjunction with stiff shearwalls was also studied. Considering the economy and effectiveness, it is concluded that shearwalls were the most feasible solution for seismic rehabilitation of such buildings.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.56 no.2
• /
• pp.47-57
• /
• 2014

This study was conducted to predict greenhouse gas (GHG) emission from paddy by future climate change scenario in Korea. Chuncheon city in Kangwon province were selected as study area. A1B Special Report on Emission Scenario (SRES) of the IPCC (Intergovernmental panel on climate change) was used to assess the future potential climate change. The rainfall and temperature was projected to increase by 8.4 % and 1.9 % (2040s), 35.9 % and 27.0 % (2060s), 19.2 % and 30.8 % (2090s), respectively, compare to the 2010s value. Under the climate change, Denitrification-Decomposition (DNDC) predicted an increase in $N_2O$, $CO_2$ and $CH_4$ emissions from paddy. The simulations resulted in annual net emissions of 0.4~2.4, 500.5~734.5 and 29.4~160.4 kg/ha/year of $N_2O-N$, $CH_4-C$ and $CO_2-C$, respectively, with a cumulated global warming potential (GWP) of $14.5{\sim}21.7t{\cdot}CO_2/ha/year$ were affected by rainfall, temperature, manure amendment and fertilizer amount. The simulation results suggested that implementation of manure amendment or reduction of water consumption instead of increased fertilizer application rates would more efficiently mitigate GHG emissions.

• The Journal of the Petrological Society of Korea
• /
• v.13 no.4
• /
• pp.201-213
• /
• 2004

The Precambrian amphibolites in the central Gyeonggi massif, Yangsuri, Gyeonggido and southeastern Okcheon metamophic belt, Mungyeonggun, Gyeongsangbukdo, Korea, were studied on the geochemical characteristics of major and trace elements, and discussed petrogenetically and geotectonically. The characteristics of major elements of the amphibolites in these study areas are igeous origin such as tholeiitic-, subalkaline and alkaline basalt. Geotectonic distinction diagrams of trace elements such as Ti-Zr-Y and Zr-Nb-Y show basaltic igneous activity of island arc and mid ocean ridge environment at central Gyunggi massif, and within plate environment at southeastern Okcheon metamorphic belt. This result shows that genetic environments of study areas are different. Especially, origin of amphibolites in central Gyeonggi massif is similar with that of western Gyeonggi massif but different with the amphibolites of Chuncheon area. Genetic environment estimated of fractional crystallization of plagioclase has no particular effect on the origin of magma because value of LREE is higher than that of HREE and Eu anomaly definitely don't be exposed.

• Korean Journal of Veterinary Service
• /
• v.30 no.3
• /
• pp.467-472
• /
• 2007

Eurasian black vulture (Aegypius monachus) belongs to family Accipitridae and is a raptor preying small birds and mammals. It is a wintering bird residing from the mid of November to the late of March in Korea. Although Eurasian black vulture population wintering at Korea is gradually increased, the efficient rescue and treatment for injured Eurasian black vultures are still problematic, due to lack of basic data. Therefore, in this survey, to obtain basic resources for establishing more efficient rescue system, we surveyed the number of Eurasian black vultures wintering at Gangwon province, wintering ecology and injury state of Eurasian black vulture. Survey area was Togyo reservoir at Cheorwon, Seonan basin at Yangoo and Wolsong reservoir at Chuncheon from November 2004 to March 2005. From 12 rescued Eurasian black vultures, physical examination, total plasma protein (TPP) and packed cell volume (PCV) were measured. To survey injury state of Eurasian black vultures wintering at Gangwon province, we surveyed the cause, morbidity and mortality from 103 Eurasian black vultures, based on medical records from animal rescue teams. The number of eurasian black vultures were gradually increased from November, peaked at Feburary, then steeply decreased at March. Eurasian black vultures showed the most vigorous activity around 1 PM within a day. In physical examination, mean body weight was $9.6{\pm}1.22kg$, body length was $1130{\pm}45.4mm$. No statistically significant difference in body weight and length between male and female eurasian black vultures was observed. Mean PCV was $40.2{\pm}2.7%$, while mean TPP was $5.86{\pm}0.8mg/dl$. The most common cause of injury and mortality was intoxication, while that of morbidity was fatigue.

• Journal of Korean Home Economics Education Association
• /
• v.30 no.1
• /
• pp.79-97
• /
• 2018

The purpose of this study was to analyze the democratic civic competencies of the activity tasks in 'the Family Life' part in Middle School Technology Home Economics textbooks according to the 2015 revised national curriculum. In order to achieve the purpose of this study, the activity tasks of six types of middle school Home Economics textbooks (for a total 12 of volumes) were analyzed. As a result, the use of the citizenship competency group was the most often recorded out of the three democratic civic competency groups and the subset of trust and value competencies also were frequently observed. Additionally, democratic civic competency was the seen most within the 'human development and family' area by the national curriculum, and showed the highest frequency in big idea, 'the relationship'. Activity tasks in the 'KH' textbooks were dealing with democratic civic competency the most. Based on the relationship between Home Economics education and democratic civic competencies, it is necessary to study the practice of classroom instruction so that students can develop democratic civic competence in 'the Family Life' by means of a Home Economics curriculum.

• Journal of The Korean Association of Information Education
• /
• v.13 no.2
• /
• pp.145-158
• /
• 2009

This study has developed indicators and criteria for measuring educational informatization level of students, teachers and parents with regard to the national educational policy. The criteria for indicator of each group are also set up. As the results of the analysis, first, 4 areas, 10 elements, 24 sub-indicators are generated as the result of development of indicator for level measure of educational informatization. And different weights are established for each area, element and sub-indicator considering the characteristics of each category. Second, generated criteria are evaluated by specialists based on the indicator of education informatization and on a scale of 100. The criteria for students are evaluated to be 80.64, the criteria for teachers to be 80.90 and the criteria for parents to be 76.52 which was found to be the lowest. Therefore, this research was completed to determine which aspect should be supported more intensively when setting the directions of future educational informatization.

• Journal of Climate Change Research
• /
• v.8 no.2
• /
• pp.109-123
• /
• 2017

The effects of recent climate change on hydrological systems could affect the Winter Olympic Games (WOG) because the event is dependent on suitable snow and ice conditions to support elite-level competitions. We investigate the long-term variability and change in winter total precipitation (P), snowfall water equivalent (SFE), and ratios of SFE to P during the period 1973/74~2015/16 in Gangwon province. The climatological percentages of SFE relative to winter total precipitation were 71%, 28%, and 44% in Daegwallyeong, Chuncheon, and Gangneung, respectively. The winter total P, SFE, and SFE/P has decreased (but not significantly), although significant increases of winter maximum and minimum temperature were detected at a 95% confidence level. Notably, a significant negative trend of SFE/P at Daegwallyeong in February, the month of the WOG, was attributable to a larger decrease in SFE related to the increases in maximum and minimum temperature. Winter wet-day minimum temperatures were warmer than climatological minimum temperatures averaged over the study period. The 20-year return values of daily maximum P and SFE decreased in Yongdong area. Since the SFE/P decrease with increasing temperature, the probability of rainfall rather than snowfall can increase if global warming continues.

• Communications of Mathematical Education
• /
• v.33 no.2
• /
• pp.123-139
• /
• 2019

This study analyzed how problem-posing tasks included in Korean middle school mathematics textbooks were distributed in terms of content area, task type, and context of task to investigate that the mathematics textbooks are giving students ample opportunities for problem-posing activities. The analysis of 10 mathematics textbooks for first grade in middle school according to the revised mathematics curriculum in 2015 found that the problem-posing tasks contained in the textbooks are insufficient in quantity and not evenly distributed in terms of content areas. There were also more problem-posing tasks with relatively moderate constraints than those with strong or weak constraints in terms of mathematical constraints. In addition, there were more problem-posing tasks that were not requiring students to make a new context, and more often camouflage contexts were used. Based on this, implications for improving mathematics problem-posing tasks in mathematics textbook were suggested.

• 한국노년학
• /
• v.30 no.4
• /
• pp.1377-1392
• /
• 2010

The purpose of this study was to understand the meaning and essence of leisure activities experienced by older females in rural communities and, in reference to that, to provide basic data to help develop health-promoting nursing intervention programs by investigating the indications of leisure and its effects on older individuals' life process. The qualitative research method of van Manen's Hermeneutical analysis and Phenomenological research are useful to study the true meaning and nature of experiences inherited from their language, belief, culture and social traditions. Consequently, the leisure that the women from the rural community were found to have experienced came down to a total of seven themes or activities: (a) to overcome loneliness through social interaction and get-togethers; (b) to achieve balance between body and mind by engaging in physical activities; (c) to try and help ease the burden on one's children; (d) to simply kill time; (e) to find oneself small pleasures; (f) to learn something new and feel proud; and (g) to live one's life as maintaining communication with the outside world. The study herein confirmed that the female elderly in rural area spend their free time on appreciating the nature, maintaining health and social interaction and hanging around with the peers of similar age to overcome economic woes and the feeling of estrangement unique in the social and economic context of rural communities.

• Journal of the Korean Society of Radiology
• /
• v.10 no.8
• /
• pp.619-627
• /
• 2016

The purpose of this study is to investigate the effect of CT contrast agent and MRI contrast agent on the area dose in the body when using automatic exposure control system in general radiography. After making rectangular holes in the center of the abdominal thickness paraffin phantom, CT contrast agent and MRI contrast agent were respectively diluted with physiological saline solution for contrast medium dilution ratio of 10:0, 9:1, 8:2, 7:3, 6:4, 5:5, 4:6, 3:7, 2:8, 1:9, 0:10%. Each experiment was set to 78 kVp, 320 mA, which is the proper condition for KUB photography, and thereafter a total of 30 inspections were made for each dilution ratio using an automatic exposure control device, and the area dose corresponding to the dilution ratio of each contrast agent, Average comparison and correlation analysis were performed on the exposure index. As a result, the CT contrast agent and the MRI contrast agent appeared different in area dose according to the dilution ratio(p<0.05), and as the dilution ratio increased, the area dose increased for CT contrast agent and MRI contrast agent(P<0.05). In each test, the exposure index showed the manufacturer's recommendation of 200-800 EI value, and the exposure index and area dose increased as the area dose increased(p<0.05). In conclusion, CT contrast agent and MRI contrast agent confirmed to increase the area dose by general imaging test using all automatic exposure control device. Therefore, it is considered that it is necessary to perform it after the contrast medium has been excreted sufficiently when using usual imaging test after using the contrast agent in CT and MRI examination.