• The Journal of the Korea institute of electronic communication sciences
• /
• v.17 no.6
• /
• pp.1213-1220
• /
• 2022

This study was conducted to understand how to derive educational methods to efficiently improve class satisfaction for 130 college students who experienced non-face-to-face classes during the last Covid-19. The appropriateness of class time, improvement of learning effect, continuity of non-face-to-face classes, and use of educational media were set as items corresponding to class satisfaction. Research was attempted to derive an educational method for efficient class satisfaction improvement by grasping the difference and relationship between variables.

• The Journal of Engineering Geology
• /
• v.26 no.1
• /
• pp.101-115
• /
• 2016

We carried out laboratory material tests on two cements (KS-1 ordinary Portland and Class G) with changing W/S (Water/Solid) and the content of fly ash in order to evaluate their physical and mechanical properties. The specimens of KS-1 ordinary Portland cement were prepared with varying W/S (Solid=cement) in weight, while those of Class G cement were prepared with changing the content of fly ash in volume but maintaining W/S (Solid=cement+fly ash). The results of the material tests show that as the W/S in KS-1 ordinary Portland cement and the content of fly ash in Class G cement increase, the properties (density, sonic wave velocity, elastic constants, compressive and tensile strengths, thermal conductivity) decrease, but porosity and specific heat increase. In addition, an increase in confining pressure and in the content of fly ash leads to plastic failure behavior of the cements. The laboratory data were then used in a stability analysis of cement sheath for which an analytical solution for computing the stress distribution induced around a cased, cemented well was employed. The analysis was carried out with varying the injection well parameters such as thickness of casing and cement, injection pressure, dip and dip direction of injection well, and depth of injection well. The analysis results show that cement sheath is stable in the cases of relatively lower injection pressures and inclined and horizontal wells. However, in the other cases, it is damaged by mainly tensile failure.

• Journal of architectural history
• /
• v.13 no.1 s.37
• /
• pp.35-51
• /
• 2004

The object of this study is upper class house in Yang-dong village with the purpose of spatial-sociological study of traditional Korean architecture. Space is the basic element of architecture and is fundamental for understanding architecture. Space, however, can be better understood through its social context rather than through its physical or psychological attributes. Space exists in a society, providing the physical environment which frames it Social environment affects the thoght of people who are members of that society. Space is built by the people in a society and is affected by their thought. Spatial-sociological study can explain a mutual relation between people and space through context. It defines characteristics of space based on mutual relations which exist among the people, the culture of society and the environment of society but also having a sociological component, study of architectural space should consider the social context. Since architectural space is built on social and cultural bases, to understand it requires various methods of study Spatial-sociological analysis is one alternative. Using space syntax, this study analyzes houses in Yang-dong village by not only defining attributes of individual houses, but also common attributes of houses in the village. Based on common attributes of houses in the village, the attributes of Yang-dong village houses can be re-defined within the social context. the results from a spatial-sociological analysis of upper class housing of the Yang-dong village are as follows; (1) Related to confucian ideas in Chosun Dynasty : A house has a dualistic center organized with 'an-chae' and 'sarang-chae'. 'an-chae' space is organized unsociably from outside. (2) Related to various space pattern of Yang-dong village House in the Chosun Dynasty period :As variations in the types of space pattern, the village house exhibit different attributes.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.25 no.6
• /
• pp.13-24
• /
• 2022

The purpose of this study is to evaluate the applicability of Ecosystem Service Matrix method in Songnisan and Hannamgeumbukjeongmaek Boeun-gun area. The assessment was carried out with 25 land cover types by 7 ecosystem values. The research area was divided by 30m x 30m cell unit and the each cell value was classified into 5 grades. The total number of cell under the investigation was 433,910 units in Songnisan and 84,975 in Boeun-gun. Class I and II area were widely spread and Class V area is narrowly distributed inside of Class III area in Songnisan. I area, II area and separately managed zone belong to Ecological Zoning map and Environmental Conservation Value Assessment Map(Environment + Ecology) were assessed Class I in Ecosystem service matrix. In conclusion, Ecosystem Service Matrix assessment based on land cover map is a rapid assessment methodology which reflecting ecosystem functions in a larger area. If it is supported with more ecosystem functions, the more precise nature value can be calculated.

• Hwankyungkyoyuk
• /
• v.20 no.3
• /
• pp.45-62
• /
• 2007

The purpose of this study was to analyze the status of environment-related teaching in elementary and secondary schools. A questionnaire survey was conducted for the study. Items in the questionnaire were developed based on the theory of environmental education and integrated education. The questionnaire was responded to 501 elementary school teachers, 273 middle school teachers, and 210 high school teachers in the city of Seoul and Kyunggi Province. The survey analysis revealed that elementary and secondary school teachers recognized 'environmental action skills' as the most important objective for school environmental education. Contrary to the teachers' expectations, it was found that there is insufficient teaching and learning materials for teaching in the domain of 'environmental action skills' and they could not confidently teach the skills in environment-related classes. For professional development of teachers in integrated environmental education, pre- and in-service programs will be developed systematically in a workshop to give teachers an opportunity to analyze teaching materials, design instruction plan, perform class trial, and evaluate the class situation for feedback. The results of this study can serve as a basic reference for improvement of environment-related subject education.

• Korean Journal of Ecology and Environment
• /
• v.42 no.4
• /
• pp.495-501
• /
• 2009

The study was conducted in 2007~2008 in order to understand preference of physical microhabitat on the $1^{st}$-class endangered species, Gobiobotia naktongensis inhabiting the Gam Stream, tributary of Nakdong River. The total number of fish caught from the study sites was 3,671 representing 7 families 24 species. There were 8 Korean endemic species including Odontobutis platycephala, and 2 introduced species (Carassius cuvieri, Micropterus salmoides) were found. According to investigation and analysis of physical microhabitat on Gobiobotia naktongensis caught in the Gam Stream, a total of 57 individuals were found at shallow depth (0.14~0.46 m) and run (0.239~0.585m $sec^{-1}$). As a result of sieve analysis, stream beds consisted of about 1% gravel and 99% sand (83.4% coarse sand, 15.6% find sand). Therefore, Gobiobotia naktongensis seemed to inhabit shallow-run with coarse sand bed than deep-pool microhabitat. The findings indicate preference of physical microhabitat on Gobiobotia naktongensis, and it is important to enhance efficiency of fish conservation and ecological restoration with understanding species-specific characteristics in microhabitat including protected species.

• The Transactions of the Korea Information Processing Society
• /
• v.2 no.5
• /
• pp.746-756
• /
• 1995

This paper describes the intractive visual programming environment using multi-view which shows the tools of visualization for called and the visualizations for called member-function flow in C＋＋ language. This research defines new visual symbols for class and constructs interactive visual programming environment of various views by using visual symbols. Our proposed interactive multi-view visual programming environment can represent visualization for representation of class and execution relationships between objects in the object-oriented language, which is easy to understand the structure of object-oriented program, therefore our proposed interactive visual programming environment enables easy program development, and can use of education and trainning for beginner in useful.

• Hwankyungkyoyuk
• /
• v.24 no.1
• /
• pp.12-25
• /
• 2011

The purpose of this study was intended to identify the difference of two sample groups for the student's awareness on the environment after ecological education in elementary school. For the elementary school participated in this study, we studied how the education influences the student's awareness on the environment using survey. The result showed that even though various kinds of environmental education programs were given to the participated group, there was no significance compared with the other group who did not participate. This was probably because the students not participated in the education program were frequently exposed to other similar types of environmental activities. In terms of the change of the student's awareness on the environment and their desire for continuing environmental education in future, 95.8% of students who participated in the survey showed positive answers. Considering the current environmental education that has mostly been made in class and the lack of variety of the education program, various types of environmental education programs are required, so schools, education system, and social groups should work together to compensate for the lack of the in-class education. In addition, the change of students awareness and altitude toward the environment proved the positive effect of the environmental program and showed the appropriateness increasing the opportunity for the environmental education.

• Korean Journal of Environment and Ecology
• /
• v.1 no.1
• /
• pp.35-45
• /
• 1987

To survey trail damage and vegetational change around trail at Bukhan Mountain National Park in Korea, field survey was executed over Bukhan mountain district during August, 1987. Trail damage was surveyed for he section of 7.18km from Ui valley to Jeongnung valley in which user's density was high. Ground vegetation was surveyed with a belt-transect method from trail edge to forest and edge species were surveyed with a belt method along trail edge. Interrelation between trail damage and user's density was not dear. Damage class II of trail showed 23.9% of the surveyed section and class III showed 8.0% and class II and III of natural trail showed 19.7% and those of facilitated trail showed 12.3%. The length of damage class II and III requiring readjustment were estimated as 3.65 km and 1.22km from the main trail course of 15.3km at Bukhan mountain district. In case of no intervention to forest by users, vegetational change around trails was appeared up to 6-8 m from trailside. But in case of intervention to forest by users, vegetational change was not coincident with the change of soil hardness and was diverse locally. Quercus mongolica, Lespedeza cyrtobotrya and Rbo-dodendron mucronulatum were appeared as Raunkiaer frequency class E, and Weigela subsessilis. Lespedeza maximowiczii, Rhododendron schlippenbachii and Sorbus alnifolid were appeared as class D at trail edge of ridge-Quercus mongolica was appeared as class E and Rhododenderon mucrounulatium. Stephanandra incisa were appeared as class D at trail edge of midslope. Rhododenron mucronulatum. Lespedeza maximowiczii and Stepanandra incisa were appeared as class D at trail edge of valley. Lespedeza cyrtobotrya. Lespedeza maximowiczii and Stephanandra incisa were appeared as class D at trail edge of valley beside motorway.

• Toxicological Research
• /
• v.25 no.3
• /
• pp.132-139
• /
• 2009

The toxicity test of ammonium persulfate was conducted to ensure of its potential toxic effects according to the single-dose acute oral toxicity study (OECD Guideline 423) and 90-day repeated dose sub-chronic oral toxicity study guideline (OECD Guideline 408) for establishing national chemical management system, and matching in the Globally Harmonized Classification System (GHS) category. In acute oral toxicity study, pasty stool, perineal contamination and temporary body weight decrease were observed after dosing 1st and 2nd challenge (300 mg/kg body weight). All test animals were dead within 6 hours after dosing at 3rd challenge (2000 mg/kg body weight). Therefore, the GHS class of test substance is considered class 4. In sub-chronic toxicity study, body weight changes, food consumptions, hematological, biochemical and pathological examination did not show any noticeable and significant differences between the administered (5, 20, 80 mg/kg body weight) and control (vehicle only) group animals. Based on these results, the no observed adverse effect level (NOAEL) is considered above 80 mg/kg body weight.