• The Journal of Korean Institute of Communications and Information Sciences
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• v.37B no.9
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• pp.806-813
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• 2012

In a cloud computing environment, various solutions were introduced to provide the service to users such as Infrastructure as a Service (IaaS), Platform as a Service (PaaS), Software as a Service (SaaS) and Desktop as a Service (DaaS). Nowadays, Mobile as a Service (MaaS) to provide the mobility in a cloud environment. In other words, users must have access to data and applications even when they are moving. Thus, to support the mobility to a mobile Thin-Client is the key factor. Related works to support the mobility for mobile devices were Mobile IPv6 and Proxy Mobile IPv6 which showed performance drawbacks such as packet loss during hand-over which could be very critical when collaborating with cloud computing environment. The proposed model in this paper deploys middleware and replica servers to support the data transmission among cloud and PMIPv6 domain. It supports efficient mobility during high-speed movement as well as high-density of mobile nodes in local mobility anchor. In this paper, through performance evaluation, the proposed scheme shows the cost comparison between previous PMIPv6 and verifies its significant efficiency.

• The KIPS Transactions:PartA
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• v.18A no.4
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• pp.135-142
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• 2011

This research is to design an effective buffer structure and its management for flash memory based high performance SSDs (Solid State Disks). Specifically conventional SSDs tend to show asymmetrical performance in read and /write operations, in addition to a limited number of erase operations. To minimize the number of erase operations and write latency, the degree of interleaving levels over multiple flash memory chips should be maximized. Thus, to increase the interleaving effect, an effective buffer structure is proposed for the SSD with a hybrid address mapping scheme and super-block management. The proposed buffer operation is designed to provide performance improvement and enhanced flash memory life cycle. Also its management is based on a new selection scheme to determine random and sequential accesses, depending on execution characteristics, and a method to enhance the size of sequential access unit by aggressive merging. Experiments show that a newly developed mapping table under the MBA is more efficient than the basic simple management in terms of maintenance and performance. The overall performance is increased by around 35% in comparison with the basic simple management.

• The Journal of the Korea Contents Association
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• v.8 no.11
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• pp.412-425
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• 2008

One of the important elements for improving academic achievement of learners in education through e-learning is to support learners to study by finding questions they want with providing various evaluation questions. However, most of question retrieval systems usually depend on keyword search based on only a syntactical analysis and/or a hierarchical browsing system classified by the topics of subjects. In such a system it is not easy to find integrative questions associated with each other. In order to improve this problem, in this paper we proposed a question management and retrieval system which allows users to easily manage questions and also to effectively find questions for study on the Web. Then, we implemented a system that gives to access questions for the domain of C language programming. The system makes it possible to easily search questions related to not only a single theme but also questions integrated by interrelationship between topics and questions. This is done by supporting to be able to retrieve questions according to conceptual interrelationships between questions from user query. Consequently, it is expected that the proposed system will provide learners to understand the basic theories and the concepts of the subjects as well as to improve the ability of comprehensive knowledge utilization and problem-solving.

• Journal of the Korean Geographical Society
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• v.46 no.6
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• pp.707-723
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• 2011

The purpose of this study was to quantitatively evaluate the effectiveness of learning management systems (LMS) in the physical geography class. The study adopted the experimental design and three classes participated in this study. The first class was controlled using only classroom lectures, the second class used PPT slides along with the classroom lectures, and the third class used online video clips along with the lectures. The experiments were conducted from the Spring Semester 2007 to the Spring Semester 2008 for the introductory physical geography course. The study results showed that online learning tools help students improve academic performance and their attitudes towards the class and the instructor. Compared to simple PowerPoint slides, voice recording attached to the visual lecture slide materials enhanced students' motivation. Class lectures with lecture slides did not improve students' scores. However, when the visual materials were combined with voice recording, the number of internet access to online class materials increased, and class attendance and students' final grades were improved. Based on the results, the instructional design model that combines classroom and online learning was suggested.

• Korean Journal of Remote Sensing
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• v.34 no.6_1
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• pp.1025-1032
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• 2018

Snow Cover is a form of precipitation that is defined by snow on the surface and is the single largest component of the cryosphere that plays an important role in maintaining the energy balance between the earth's surface and the atmosphere. It affects the regulation of the Earth's surface temperature. However, since snow cover is mainly distributed in area where human access is difficult, snow cover detection using satellites is actively performed, and snow cover detection in forest area is an important process as well as distinguishing between cloud and snow. In this study, we applied the Normalized Difference Snow Index (NDSI) and the Normalized Difference Vegetation Index (NDVI) to the geostationary satellites for the snow detection of forest area in existing polar orbit satellites. On the rest of the forest area, the snow cover detection using $R_{1.61{\mu}m}$ anomaly technique and NDSI was performed. As a result of the indirect validation using the snow cover data and the Visible Infrared Imaging Radiometer (VIIRS) snow cover data, the probability of detection (POD) was 99.95 % and the False Alarm Ratio (FAR) was 16.63 %. We also performed qualitative validation using the Himawari-8 Advanced Himawari Imager (AHI) RGB image. The result showed that the areas detected by the VIIRS Snow Cover miss pixel are mixed with the area detected by the research false pixel.

• Journal of the Korea Convergence Society
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• v.12 no.3
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• pp.177-186
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• 2021

The 2015 revised curriculum is structured around the core competencies of the 21st century, this is in line with the world's flow of education, such as OECD Education 2030. A future practical leading model was studied to provide a variety of creative teaching and learning experiences to elementary and Secondary students using intelligent information technology to cultivate core competencies such as ICT and computing thinking. In order for this practical model to stably settle the school field, the training was planned and operated to strengthen the creative convergence education capacity required by the teachers at the unit school through various types of the training. In particular, a nationwide administrators training program was operated for three years, reflecting the new curriculum, teaching and learning methods, and evaluation that can lead to future convergence talent training. In this paper, the perception of creative convergence education was investigated and analyzed considering the influence that administrators may have on the school field. Based on this, through the three-year operation results of the training, it was intended to establish a new training method for stable access to future creative convergence education under the post-corona era's social issues.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.3
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• pp.619-623
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• 2018

This paper aimed to design a computer course teaching-learning strategy for (m-learning?) to be used in a Problem Based Learning (PBL) environment. The research findings were as follows. Firstly, learning contents were provided as educational tools for mobile device usage. The educational contents provided were designed for effective usage on mobile devices, such as smartphones, thereby making mobile devices suitable for use as learning tools. Secondly, learning contents for PBL were provided. PBL problems (for computer engineering courses) were made with the principles of teaching plans. The learning objectives were achieved through the problem-solving progress of the learners and their self-directed and cooperative learnings. Thirdly, learning resources were provided that were easily accessible through smartphones, laptops and PDAs. This study is about the PBL instructional design of creative engineering design subjects, which aims to foster talent. The PBL model developed in this study consists of Analysis, Design, Development, Implementation, and Evaluation. We made a plan for creative engineering design subjects based on PBL, and focused on the process of PBL. This research was able to establish the basis for PBL usage in Engineering Schools and help achieve its ultimate goal of endowing professional intellectuals with creative problem-solving abilities.

• YAKHAK HOEJI
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• v.54 no.4
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• pp.258-269
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• 2010

As people are easy to access the National Health Insurance, medical health service has been increased. It contributed to extend human's average life expectancy and to get better health care. But also increased unnecessary health service or inappropriate drug use. Therefore, DUR (Drug Use Review) is needed to induce appropriate drug use. The purpose of this study is to evaluate outpatient prescriptions by General Practitioner (GP) and Specialized Practitioner, especially indication for ENT referral including common cold which is the frequent indications that have patient see doctor. This study was reviewed retrospectively prescriptions for ENT referral collected at the A pharmacy for ENT Clinic in Cheong-Ju, B pharmacy for GP Clinic in BoEun from Feb 2nd, 2009 to Feb 28th, 2009. Each pharmacy located closed to the each enrolled clinic. The numbers of collected prescriptions were each A pharmacy (n=2501), B pharmacy (n=1343). This study was classified Drug Related Problems (DRPs) those prescriptions had as total 6 groups according to following 6 categories; 1) Unnecessary Drug, 2) Wrong Drug, 3) Low Dose, 4) Overdose, 5) Wrong Instruction, 6) Wrong Combination. In results, Specialized Practitioner's prescriptions had more DRPs than General Practitioner's prescriptions (ENT 155.34% vs GP 130.01%). In detail, Specialized Practitioner's prescriptions had more DRPs in Low Dose (ENT 16.95% vs GP 4.77%), Overdose (ENT 6.72% vs G.P 5.51%), Wrong Instruction (ENT 7.91% vs GP 5.81%), Wrong Combination (ENT 29.31% vs GP 25.09%). These DRPs would be caused from lack of consideration for dosage and drug interaction. General Practitioner's prescriptions had more DRPs in Unnecessary Drug (ENT 70.37% vs GP 78.85%), Wrong drug (ENT 4.12% vs GP 9.98%). These DRPs would be associated with drug selection. This study was assumed that Specialized Practitioner is better prescriber than General Practitioner because Specialized Practitioner complete additional intern and residency training. But, Specialized Practitioner is not always better prescriber than General Practitioner. Furthermore, prescriptions of both Specialized Practitioner and General Practitioner had many problems. In conclusion, It could be cut down the excessive medical expense and expected more efficient medical care by reducing DRPs, thus contributing to the improvement of national health. In order to pharmacist must have good professional ability of pharmacotherapy to help the physician for the drug selection.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2008.10a
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• pp.106-112
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• 2008

Personalization is user oriented dynamic method based on user preferences for easy access to what users want to view or get. It has become more important in mobile domain with rapid growth of wireless Internet and mobile phone market after success of web based market and therefore, it can be applied to service of spatial analysis result. In this paper, spatial analysis using user profile and notification service methods are proposed as one of personalized spatial data service methods for mobile users. A service system for spatial analysis with user profile is designed to prove possibility of spatial analysis based on user preferences and notification service is also designedto show generated output can be sent to user's mobile devices efficiently to make users informed of preferred information. Prototype system is implemented and it is applied to real estate data that has many selectable conditions by users. Information service based on user preferences can be applied to spatial data by using proposed system and it is efficient when cache module is used to shorten response time. Various user models for application domains and performance evaluation methods need to be developed in the future.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.5
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• pp.697-708
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• 2016

As the needs for fast wireless communication technology in various fields, including companies, individuals, etc., grows, many research projects related to the coverage of propagation are being carried out for plaining optimized communication services. On the other hand, there are some limitations in surveying and analyzing propagation in highland areas. To provide a better communication service of a new service, a range of radio environment conditions based on a wide radio bandwidth (selection of propagation model, correction of value in accordance with radio bandwidth, etc.) should be considered. In particular, radio environment conditions are becoming increasingly sophisticated. By the early detection of real-time changes in the radio spectrum, which is based on an examination and research of regional occupied band width condition, proper measures should be established. To make a proper solution of above, the basic real-time analysis of spectrum distribution status by regional groups is necessary. In addition, the establishment of prompt measures should be enable by stored or analyzed radio data. In an attempt to predict reliable propagation coverage, this thesis examines the limited propagation data with HTZ Warfare, which were collected from domestic high land sites faced with limited access. Furthermore, a comparative result value evaluation for an optimized propagation model was performed through testing simulations, and frequency-dependent and propagation model-dependent analysis.