• Communications of Mathematical Education
• /
• v.32 no.2
• /
• pp.147-174
• /
• 2018

The purpose of this study was to verify the effect of mathematical disposition and attitude through the foster self-confidence and learning motivation by STAD cooperative learning. For this purpose, we made up an experimental class. And then we investigated the students' change in these aspects after the foster self-confidence and learning motivation by STAD cooperative learning. As a result of the experiment, we find that significant changes on the students' mathematical disposition and attitude utilizing the foster self-confidence and learning motivation by STAD cooperative learning. Therefore, in this study, I want to solve the particular problems that follow. First, what is the reaction of utilizing the foster self-confidence and learning motivation by STAD cooperative learning mathematical program for students? Is it effective utilizing the foster self-confidence and learning motivation by STAD cooperative learning to improve students' mathematical disposition? Third, does utilizing the foster self-confidence and learning motivation by STAD cooperative learning have a positive impact on students' mathematical attitude?

• Journal of the Korean Solar Energy Society
• /
• v.27 no.2
• /
• pp.111-119
• /
• 2007

The annual mean temperature of South Korea has risen by $1.3^{\circ}C$ for last 100 years by urbanization and industrialization. Especially, the frequency of unusual hot weather in summer increases for a long time and the frequency of unusual cold weather in winter clearly decreases. In recently, The considerable portion of curtain wall system is appled to building skin in domestic. As related to this, the Korea Institute of Construction Technology devised the box typed double skin facade(It is occasionally called as FDFS : Functional Double Facade System) as an alternative that reflects the distinctive local climate and saves cooling energy. Two mock-ups($49m^*4.9m$) applied to single skin(curtain wall) and double skin each were monitored under the outdoor condition. Therefore, the characteristics of natural ventilation and cooling energy consumption of each window had been analyzed in real time. The results of this study are summarized as follow, Analysis of the experiment on an air conditioner: the indoor temperature of the chamber with FDFS is lower than that of the chamber with single skin facades by $3{\sim}6$ degrees(C). A temperature variation of about $1{\sim}2$ degrees between the 0.2m and 1.7m height of the mock-up occurs in FDFS, while that of about maximum 7 degrees occurs in single skin facade at noon with abundant intensity of solar accident. Also, 67 percent of energy consumption for air conditioning has been saved.

• Nuclear Engineering and Technology
• /
• v.48 no.4
• /
• pp.881-892
• /
• 2016

Following the Fukushima accident and its extended station blackout, attention was brought to the importance of the spent fuel pools' (SFPs) behavior in case of a prolonged loss of the cooling system. Since then, many analytical works have been performed to estimate the timing of hypothetical fuel uncovery for various SFP types. Experimentally, however, little was done to investigate issues related to the formation of a flammable gas mixture, distribution, and stratification in the SFP building itself and to some extent assess the capability for the code to correctly predict it. This paper presents the main outcomes of the Experiments on Spent Fuel Pool (ESFP) project carried out under the auspices of Swissnuclear (Framework 2012-2013) in the PANDA facility at the Paul Scherrer Institut in Switzerland. It consists of an experimental investigation focused on hydrogen concentration build-up into a SFP building during a predefined scaled scenario for different venting positions. Tests follow a two-phase scenario. Initially steam is released to mimic the boiling of the pool followed by a helium/steam mixture release to simulate the deterioration of the oxidizing spent fuel. Results shows that while the SFP building would mainly be inerted by the presence of a high concentration of steam, the volume located below the level of the pool in adjacent rooms would maintain a high air content. The interface of the two-gas mixture presents the highest risk of flammability. Additionally, it was observed that the gas mixture could become stagnant leading locally to high hydrogen concentration while steam condenses. Overall, the experiments provide relevant information for the potentially hazardous gas distribution formed in the SFP building and hints on accident management and on eventual retrofitting measures to be implemented in the SFP building.

• Journal of Radiation Protection and Research
• /
• v.42 no.1
• /
• pp.48-55
• /
• 2017

Background: Simultaneous detection of neutrons and gamma rays have become much more practicable, by taking advantage of good gamma-ray discrimination properties using pulse shape discrimination (PSD) technique. Recently, we introduced a commercial CLYC system in Korea, and performed an initial characterization and simulation studies for the CLYC detector system to provide references for the future implementation of the dual-mode scintillator system in various studies and applications. Materials and Methods: We evaluated a CLYC detector with 95% $^6Li$ enrichment using various gamma-ray sources and a $^{252}Cf$ neutron source, with validation of our Monte Carlo simulation results via measurement experiments. Absolute full-energy peak efficiency values were calculated for gamma-ray sources and neutron source using MCNP6 and compared with measurement experiments of the calibration sources. In addition, behavioral characteristics of neutrons were validated by comparing simulations and experiments on neutron moderation with various polyethylene (PE) moderator thicknesses. Results and Discussion: Both results showed good agreements in overall characteristics of the gamma and neutron detection efficiencies, with consistent ~20% discrepancy. Furthermore, moderation of neutrons emitted from $^{252}Cf$ showed similarities between the simulation and the experiment, in terms of their relative ratios depending on the thickness of the PE moderator. Conclusion: A CLYC detector system was characterized for its energy resolution and detection efficiency, and Monte Carlo simulations on the detector system was validated experimentally. Validation of the simulation results in overall trend of the CLYC detector behavior will provide the fundamental basis and validity of follow-up Monte Carlo simulation studies for the development of our dual-particle imager using a rotational modulation collimator.

• Korean Journal of Digital Imaging in Medicine
• /
• v.10 no.1
• /
• pp.5-6
• /
• 2008

In this study, using an experiment, in certified an error between each system of SUV (standardized uptake value) that is one of the main analyses to diagnose a tumor in PET/CT, so, it would assure reliability and help to diagnose any lesions accurately. That is, a detailed analysis progressed. as all images reconstructed every setting time, then, clinical reliability between each system was expressed numerically at MBq/mL and SUV. Therefore, this study is considered that flexibility of follow-up using diverse system was insured, and it helps to offer accurate and beneficial information for diagnosis of various fields.

• Hwankyungkyoyuk
• /
• v.24 no.3
• /
• pp.1-17
• /
• 2011

The purpose of this study was to develop and apply the pro-environmental housing life educational program to improve of pro-environmental attitude for upper grade of elementary school and to verify its effectiveness and influence. To achieve the purpose, documentary and investigatory research was conducted and thereafter the program developed and implemented following 5 stages of analysis, design, development, implement and evaluation. The experiment was made progress as two-group pretest-posttest design, and the program was applied to a class for two hours every week in discretionary activity class for 6 weeks. A reconstructed questionnaire through Kim et al.(2000)'s test tool was used to survey the effects of students's attitudes on environment. The major results were as follows. First, the developed program focused on the main contents of pro-environmental housing life based on ESD. Second, this program had a positive effect on elementary school students' environmental attitude. Third, this program had a positive correlation(.588~.712) among the 3 subdomains of verbal commitment, actual commitment and affect. Fourth, according to qualitative analysis, students appear to be more concerned and interested in the pro-environmental housing life and environmental problem. In conclusion, the pro-environmental housing life educational program based ESD has a positive effect on elementary school students' environmental attitude. Therefore, more intensive research and follow-up study on teaching and learning methods should be highly considered.

• Environmental and Resource Economics Review
• /
• v.30 no.1
• /
• pp.1-26
• /
• 2021

This paper aims to examine economic values of green spaces for non-Capital areas that have been rarely studied. Choice experiments were applied to two dissimilar but adjoining areas: The City of Jeonju and Wanju County. Split-sample surveys allowed to compare between apartment dwellers and single- or multi-family house dwellers, and across differing types of green spaces. According to the results, significant and substantial preferences might prevail not only for large cities, but also for agricultural areas. The mean willingness-to-pay (WTP) values of apartment dwellers for the view of a river/lake or mountain were generally smaller than those of Seoul, while the overall access values showed the opposite relationships. House dwellers in Jeonju showed substantially larger economic values for green spaces than those of the counterparts in Seoul, except for the access value of a river/lake. The findings grant follow-up studies investigating the reasons for the anomalous preferences particularly in Jeonju and identifying new management policies for non-Capital areas.

• The Journal of the Convergence on Culture Technology
• /
• v.8 no.5
• /
• pp.241-249
• /
• 2022

This study intended to explore the instructional effects of e-PBL which means an expansion of availability of PBL using technology. To achieve the goal of this study, a major selective subject was redesigned systematically so that e-PBL activities could be implemented for 4-weeks during the entire semester. Participants' reactions to the e-PBL experience during the experiment period were collected and analyzed. Results of analysis showed that participants could overcome the difficulties and frustrations at an early stage, adapted and assimilated to the e-PBL based instructional environment progressively, and satisfied at the e-PBL activity experiences in overall. They participated in solving the authentic problems with ownership and could solve them effectively and efficiently through frequent communication and collaboration with teammates. Results of this study showed the possibility of instructional innovation of a teacher development institute through e-PBL. Follow-up studies which extend the analyses of the effects of e-PBL based on this study are necessary to additionally verify the effects of e-PBL.

• Journal of People, Plants, and Environment
• /
• v.22 no.3
• /
• pp.255-268
• /
• 2019

Horticultural therapy, as a kind of complementary alternative therapies using nature as a medium, is an intervention method that can be applied to various subjects by utilizing horticultural activities that anyone can enjoy as a leisure activity. This research defined the resilience of individuals as a personal characteristic, and examined differences in the intervention effect of horticultural activities depending on the level of resilience. The results obtained in this study can be utilized in planning a horticultural activity program and setting the purpose and goals of horticultural activity programs. The subjects of this study were divided into the high resilience experimental group (Group A), the low resilience experimental Group (Group C), the high resilience control group (Group B), and the low resilience control group (Group D). The experiment was conducted in the campus of G University from September to November 2017, and the experimental group participated in the program once per week, a total of 10 sessions. The Korean version of the Connor-Davidson Resilience Scale, autonomic nervous assessment, and the interpersonal relationship change scale were carried out as pre- and post-assessment. Statistical analysis was performed using a non-parametric test. Group A showed statistically significant positive changes in relaxation of physical tension and stability. In conclusion, those with high resilience showed the higher intervention effects of horticultural activities on physical relaxation and stability than those with low resilience. However, there were some possible limitations in this study. Since the number of subjects was small and subjects were limited to college students, it is impossible to generalize the results of this study. Therefore, it is necessary to conduct follow-up studies to address and overcome these limitations.

• Korean Journal of Soil Science and Fertilizer
• /
• v.45 no.6
• /
• pp.877-881
• /
• 2012

This research was carried out to investigate the interaction effect of slope gradient and rainfall intensity on soil loss with rainfall simulator. The soils used in this experiment were saprolite, Chahang series which distributed extensively in Daegwanryong. Slope gradient applied was 0.5, 7, 15 and 30%. Rainfall intensity applied was 20, 60 and $90mm\;hr^{-1}$. The result obtained can be summarised as follow; Overall, Chahang series suffered more losses than saprolite. Chahang series shows the immediately large increase of soil loss with the increasing soil gradient and rainfall intensity. However, saprolite shows a little increasing loss up to 7% gradient and abruptly increasing loss logarithmically over 7% gradient in soil slope. In combination of slope gradient 15, 30% and rainfall intensity 60, $90mm\;hr^{-1}$ processing, both soil erosion happened significantly. And there was no significant difference between the two soils. Because Chahang series have the danger of soil loss with low slope gradient and rainfall intensity, we should give greater attention to soil management in Chahang series.