• Proceedings of the KSRS Conference
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• 2008.10a
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• pp.224-227
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• 2008

Land cover and its changes, affecting multiple aspects of the environmental system such as energy balance, biogeochemical cycles, hydrological cycles and the climate system, are regarded as critical elements in global change studies. Especially in arid and semiarid regions, the observation of ecosystem that is sensitive to climate change can improve an understanding of the relationships between climate and ecosystem dynamics. The purpose of this research is analyzing the ecosystem surrounding the Gobi desert in North Asia quantitatively as well as qualitatively more concretely. We used Normalized Difference Vegetation Index (NDVI) derived from SPOT-VEGETATION (VGT) sensor during 1999${\sim}$2007. Ecosystem monitoring of this area is necessary because it is a hot spot in global environment change. This study will allow predicting areas, which are prone to the rapid environmental change. Eight classes were classified and compare with MODerate resolution Imaging Spectrometer (MODIS) global land cover. The time-series analysis was carried out for these 8 classes. Class-1 and -2 have least amplitude variation with low NDVI as barren areas, while other vegetated classes increase in May and decrease in October (maximum value occurs in July and August). Although the several classes have the similar features of NDVI time-series, we detected a slight difference of inter-annual variation among these classes.

• Journal of Agricultural Extension & Community Development
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• v.22 no.3
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• pp.321-332
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• 2015

For the purpose of enhancing the use of social service in classrooms, this research focuses on the relationships between presence and learning flow, key words in the analysis of college classes using Facebook. The results of this study are as follow. First, social presence(${\ss}=.33$, p=.000), emotional presence(${\ss}=.29$, p= .000), cognitive presence(${\ss}=.20$, p= .010) were found to be significant according to cognitive flow experience the result of analysis of multiple regression. all regression coefficients were positive. Second, emotional presence(${\ss}=.42$, p=.000) and social presence(${\ss}=.27$, p=.000), cognitive, presence(${\ss}=.17$, p=.015) were found to be significant according to emotional flow experience the result of analysis of multiple regression. all regression coefficients were positive. Third, social presence(${\ss}=.37$, p=.000) of the three variables were found to be significant according to behavioral flow experience the result of analysis of multiple regression.

• Geotechnical Engineering
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• v.11 no.2
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• pp.71-78
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• 1995

In this paper, a study was performed on classifying a rock mass into multiple classes as in rock mass classification systems, such as RMR system and Q system etc. In a situation with only limited quantitative data available, it was sought to employ a way of incorporating qualitative data in a systematical and reasonable manner. It is based on the realm of Geostatistics. In particular, indicator kriging technique, which is one of non-parametric approaches, was used. As a selection criterion for an optimal classification, the cost of errors was adopted. As a result, the binary rock classification method developed before was extended and generalized for multiple rock classification with its total number of classes unlimited.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.1A
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• pp.59-66
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• 2008

This paper presents a spectrum sharing and allocation problem in multiple network operators(NOs). Most of previous works as to dynamic spectrum allocation(DSA) schemes have presented the DSA gain achieved by utilizing the time or regional variations in traffic demand between multi-network operators(NOs). In this paper, we introduce the functionalities required for the entities related with the spectrum sharing and allocation and propose a spectrum allocation algorithm while considering the long-term priority(or fairness) between NOs, the prioritybetween multiple class services, and the urgent bandwidth request. It was shown that the proposed algorithm with priorities between multiple class services could sustain better satisfaction ratio(SR) than the fixed allocation schemes or one without priority under different traffic patterns. Therefore, we conclude that the proposed DSA with priorities between multiple class services and network operators could provide the fairness between service classes of network operators and effective negotiation procedure for urgent bandwidth request by users.

• Journal of Korea Entertainment Industry Association
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• v.13 no.6
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• pp.187-202
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• 2019

The main goal of this study is to investigate influence of trust in physical education (PE) teachers and immersion experience in PE classes on attitude and satisfaction during PE classes. Total 863 middle school students in Gwang-ju metropolitan area were recruited by utilizing a convenience sampling method. All data were analyzed by using SPSS statistic program ver. 25.0 (frequency analysis, exploratory factor analysis, reliability analysis, correlation analysis, multiple regression analysis). Alpha was set at 0.05. The results of this study is summarized as in the following. First, all sub-factors of trust in the PE teachers partially positively or negatively influence sub-factors of attitude during PE classes. Second, sub-factors of satisfaction during PE classes were partially positively affected to trust in the PE teachers. Third, Attitude during PE Classes were found to have partial positive influence on immersion experience in PE classes. Fourth, sub-factors of immersion experience in PE classes have partial positive effect on the sub-factors of satisfaction during PE classes. Thus, in order to the positive attitude and greater satisfaction during PE classes, it is important to establish the trust of PE teachers through maintaining interaction with students, constructing better systemic class, and creating the class conditions based on considering students' ability. In addition, in order to enhance immersion experiences of students during PE classes, it is necessary to set up learning goals and tasks based on ability of students, to study various teaching method, and to make only focusing on the performance based PE classes without grading.

• Journal of the Korea Society for Simulation
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• v.14 no.1
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• pp.33-42
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• 2005

Service Level Agreement (SLA) is a service providing scheme by a service class agreement between a user and a service provider SLA allows that a user can select an expected service class in various service classes provided from a service provider. Recently, SLA management is adapted to support the end-to-end Qos for service users in Beyond 3 Generation (B3G) networks. In B3G networks, SLA provides multiple service classes on access networks so that service classes should be managed to assure the service satisfaction for users. In this paper, we propose a dynamic Qos management scheme by IP traffic class controlling based on SLA in B3G networks. Also, to manage dynamic traffic service, we consider Differentiated services (Diffserv) mechanism for the resource management by SLA. An If service traffic class on SLA can be dynamically changed by Diffserv traffic management to support dynamic end-to-end Qos. Hence, in this paper, we consider the buffer threshold scheme for controlling traffic loads and the traffic level control scheme for implementing the dynamic traffic management by the SLA.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.12
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• pp.4324-4342
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• 2014

Previous papers analyzed the throughput performance of the CDMA ALOHA system in Rayleigh fading channel, but they assume that the channel coefficient of Rayleigh fading was the same in the whole packet, which is not realistic. We recently proposed the finite-state Markov channel (FSMC) model to the throughput analysis of DS uncoded CDMA/unslotted ALOHA networks for fixed length data traffic in the mobile environment. We now propose the FSMC model to the throughput analysis of coded DS CDMA/unslotted ALOHA networks with variable length data traffic and one or two user classes in the mobile environment. The proposed DS CDMA/unslotted ALOHA wireless networks for two user classes with access control can maintain maximum throughput for the high priority user class under high message arrival per packet duration.

• International Journal of Contents
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• v.17 no.2
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• pp.9-19
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• 2021

The purpose of this survey-based study was to investigate high school students' perceptions of mathematics teachers' implementation of Universal Design for Learning (UDL)-based practices and technology in their mathematics classes in 2017. A total of 303 high school students in South Korea participated in this online survey on teachers' use of technology for instructional practices, the frequency of technology tool use, and the meeting of UDL guidelines in mathematics instruction. According to frequency analysis, high school students generally perceived their teachers' mathematics teaching as somewhat positive in providing multiple means of representation, action and expression, and engagement. However, mathematics teachers' implementation of technology tools in their mathematics classes was generally limited. This study indicated significant and positive relationships between variables regarding the use of technology tools and teachers' efforts to follow the UDL guidelines. Applying the Chi-squared test, we further examined how each survey result differed according to high school students' academic achievements and grade levels.

• The Journal of the Convergence on Culture Technology
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• v.9 no.3
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• pp.471-480
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• 2023

The purpose of this study is to confirm the effect of recording online classes and real-time video classes on other behaviors, lecture satisfaction, and lecture flow in during the COVID-19 period. Data were collected and analysis using a structured questionnaire from May 20th to June 4th in 2021 for 550 nursing students in the D University. As a result of the study, it was found that there were more others behaviors in record online classes than in real-time online classes (t=-2.00, p=.046), lecture satisfaction(t=-1.54, p=.124) and lecture flow in real-time online classes it was higher in the record online classes (t=-.63, p=.529), but it was not statistically significant. However, the 2nd year students who participated in the two types of online classes showed statistically significantly higher lecture satisfaction (t=13.55, p=.000) and lecture flow(t=4.48, p=.004). And 4 th grade students of others behaviors was statistically significantly lower (t=4.68, p=.003). In the multiple regression analysis, the main factor affecting lecture flow was lecture satisfaction, and the explanatory power of the model was 55.1% in record online classes (F=128.49, p <.01), and in real-time classes 47.2%(F=77.24, p<.01). In the future, research should be conducted to confirm the difference between the two types of online classes of the same instructor and the difference in other things, lecture satisfaction, and class commitment that appear after applying learner-centered learning.

• The Mathematical Education
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• v.47 no.4
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• pp.405-419
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• 2008

The purpose of this study is to find oui the effects of teaching mathematical concepts by designing and applying teaching and learning programs that takes into consideration the students' strong intelligence, through the teaching and learning strategies based on the multiple intelligences theory. For this study, developmental and experimental research was conducted. In the developmental research part of the study, teaching and learning programs for teaching the concept of multiplication were designed and the activities based on the multiple intelligences were chosen. On the other hand, in the experimental research part, the data acquired from the application of nonequivalent control group pretest-posttest design in the actual classes was processed and analyzed. The results above indicate that the teaching and learning program based on the multiple intelligences theory improved the students' overall understanding of mathematical concepts by providing various types of activities. In addition, this program helped students to increase their confidence and generate a positive attitude towards learning math.