• Journal of Positioning, Navigation, and Timing
• /
• v.9 no.3
• /
• pp.169-173
• /
• 2020

Location-based services are used as core services in various fields. In particular, in the field of public services such as emergency rescue, accurate location estimation technology is very important. Recently, the technology of tracking the location of self-isolation subjects for COVID-19 has become a major issue. Therefore, location estimation technology using personal smart devices is being studied in various ways, and the most widely used method is to use GPS. Other representative methods are using Wi-Fi, Pedestrian Dead Reckoning (PDR), Bluetooth Low Energy (BLE) beacons, and LTE signals. In this paper, we introduced a positioning technology using deep learning based on LTE Channel State Information-Reference Signal (CSI-RS) data, and confirmed the possibility through an outdoor location estimation experiment using a commercial LTE signal.

• The Journal of Korean Association of Computer Education
• /
• v.11 no.3
• /
• pp.57-65
• /
• 2008

In the web- based educational system, how to improve interaction among learners are very important by the Internet. Therefore interpersonal interaction is essential for a good educational environment. In this paper, a web-based PBL(Problem-Based Learning) system is designed and implemented to improve learner's interaction. I investigated how the method for improving interaction affect PBL activities and how students perceive the web-based PBL learning experience. The result of experiment showed that the suggested system facilitated learners' self-directed learning process and interaction.

• Structural Engineering and Mechanics
• /
• v.57 no.4
• /
• pp.763-783
• /
• 2016

A methodology based on Teaching Learning-Based Optimization (TLBO) algorithm is proposed for optimum design of reinforced concrete retaining walls. The objective function is to minimize total material cost including concrete and steel per unit length of the retaining walls. The requirements of the American Concrete Institute (ACI 318-05-Building code requirements for structural concrete) are considered for reinforced concrete (RC) design. During the optimization process, totally twenty-nine design constraints composed from stability, flexural moment capacity, shear strength capacity and RC design requirements such as minimum and maximum reinforcement ratio, development length of reinforcement are checked. Comparing to other nature-inspired algorithm, TLBO is a simple algorithm without parameters entered by users and self-adjusting ranges without intervention of users. In numerical examples, a retaining wall taken from the documented researches is optimized and the several effects (backfill slope angle, internal friction angle of retaining soil and surcharge load) on the optimum results are also investigated in the study. As a conclusion, TLBO based methods are feasible.

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.10 no.3
• /
• pp.61-70
• /
• 2014

The government supports the various systems on the premise of life-long education for improving the qualification of its people and supporting the lifelong career system. These systems help the educational activities for every generation from the teens. Each government department supports the learning activities for those who are related. In addition, each government department systemizes the regular education for advancing the performance of civil servant, by obliging a self-directed system to their member as well as by reflecting this educational activities in a promotion. This style of learning is provided not only offline but also online. However, not all necessary educational contents is furnished within the department. It is sometimes necessary to cooperate with the commissioned education and a professional educational institution. This thesis suggests three model systems while comparing one another. This paper suggests three system model. The first model is e-contents open place. The second model is e-contents open place. Finally, the suggest model is mixed form.

• Journal of Advanced Marine Engineering and Technology
• /
• v.26 no.5
• /
• pp.581-588
• /
• 2002

A fuzzy learning control algorithm is proposed in this paper. In this method, two fuzzy controllers are used as a feedback and a feedforward type. The fuzzy feedback controller can be designed using simple knowledge for the controlled system. On the other hand, the fuzzy feedforward controller has a self-organizing mechanism and therefore, it does not need any knowledge in advance. The effectiveness of the proposed algorithm is demonstrated by experiment on the position and force control problem of a parallelogram type robot manipulator with two degrees of freedom. It is shown that the rapid learning and the robustness can be achieved by adopting the proposed method.

• Journal of the Korean Institute of Educational Facilities
• /
• v.7 no.1
• /
• pp.57-66
• /
• 2000

Learning for educating creative thinking and problem solving abilities and for future-oriented method should have appropriate laboratory, experimental equipments and appliances. Technology laboratory model pertinent to experiment or activity for educating creative persons is suggested in the following : (1) It is considered that many problems of current education result from an overcrowded classes. The number of students per laboratory should be $30{\sim}40$ persons. (2) There should be sufficient activity spaces for students. Unlike normal classrooms laboratory should have various tools and materials, information, facility and equipment. (3) Flexible activity spaces for various activities should be provided for groups and individuals. (4) Safety facilities should be provided sufficiently. (5) Learning experiences of collection, analysis and utilization of information should be given. (6) Laboratories should be designed to be a place for self-propelled learning. They should be designed to be able to learn by individuals and small groups after taking into consideration the individual differences as students differ in interest, curiosity and ability.

• Journal of Engineering Education Research
• /
• v.17 no.6
• /
• pp.77-83
• /
• 2014

This paper deals with the practical experience and lessons to develop the criteria for evaluating projects in Computer Science & Information Engineering. In engineering education, project-based learning is different from problem-based learning. Project tasks are closer to professional reality. And self-direction is stronger in project work. In this paper, the development of project evaluation criteria is introduced with consideration of these differences. It is explained through running examples of basic project courses in Computer Science & Information Engineering.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.3 no.2
• /
• pp.134-146
• /
• 2009

Traffic classification seeks to assign packet flows to an appropriate quality of service(QoS) class based on flow statistics without the need to examine packet payloads. Classification proceeds in two steps. Classification rules are first built by analyzing traffic traces, and then the classification rules are evaluated using test data. In this paper, we use self-organizing map and K-means clustering as unsupervised machine learning methods to identify the inherent classes in traffic traces. Three clusters were discovered, corresponding to transactional, bulk data transfer, and interactive applications. The K-nearest neighbor classifier was found to be highly accurate for the traffic data and significantly better compared to a minimum mean distance classifier.

• East Asian mathematical journal
• /
• v.32 no.2
• /
• pp.175-192
• /
• 2016

This study aimed to understand the needs of changes in the teaching-learning environment in the university and to develop the liberal art subject of mathematics. The changes of mathematical belief in the university students were investigated to understand how the liberal art subject of mathematics affected them related to mathematics. Upon the study results, the significant changes were occurred from the utility factor on the subject of mathematics in mathematical belief, the importance factor of the answers in the teaching-learning belief, teaching activity factor of the teachers, and inborn capability factor in the belief on the self-concept. The meaningful learning environment and teaching method for the liberal art subject of mathematics are suggested further by these results.

• Journal of the Korean Institute of Rural Architecture
• /
• v.16 no.4
• /
• pp.67-74
• /
• 2014

Departmentalized Classroom System is new school operating system to apply social needs. Recent social needs are characterized as learning environment and self-learning system. The purpose of this study is to provide basic data for equal learning environment condition in middle school applying departmentalized classroom system. This study has progressed through analyzing on 11 remodelling case of middle school in Gangwon-Do. The method of this study is visiting middle schools that operate the system, grasping the condition for environment composition, and investigating and analyzing practical use of the environment. The results of this study are summarized as follows: 1) The space compositions for departmentalized classroom system are generally desirable, but some schools take irrational space composition, especially on home base-teacher laboratory, classroom-teacher laboratory. 2) The space area distributions are different in every school. This result is based on not taking standard criterion on space area distribution.