• Journal of Digital Contents Society
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• v.5 no.3
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• pp.234-238
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• 2004

The system facilities in mobile communications networks are mainly classified into the coverage and usage in the viewpoint of the investments requirements. Based on the classification criterion, the interconnection charging between the wired operators art wireless operators is determined. In this paper, to decide the scale of the interconnection charging a new classification method is proposed by using the system capacity(Erlang, throughput) and subscriber`s estimated demand. The coverage ratio is first evaluated for each facility, and then more efficient interconnection charging model will be presented.

• Journal of Korea Society of Digital Industry and Information Management
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• v.15 no.4
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• pp.137-148
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• 2019

This paper is designed to examine the effectiveness of Computational Thinking and programming awareness by designing and applying programming classes using Havruta. In the present society, where the Fourth Industrial Revolution was in full swing, the capacity to be equipped has changed, and the education has been changed accordingly. Programming education is logically capable of thinking and improves comprehensive problem solving skills. This direction of programming education allows us to get ideas for solving problems based on computing thoughts and to create our own creative results. However, because they require the grammar of the programming language and many additional abilities, they are not easy for learners, and individual differences in competencies make learning less immersive and interesting. In this paper, to solve the problems of the uniform programming class, this study is designed and applied to the class applying the Jewish traditional teaching method, Havruta's teaching method, to find out the effect of computing thinking and programming perception.

• Proceedings of the IEEK Conference
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• 2002.06d
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• pp.231-234
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• 2002

As control programs are becoming larger and more complex, the capacity of a microprocessor in a TV set needs to have a CPU with 32 bits or more. Also the embedded system such like a digital TV set uses RTOS (Real Time Operating System)[1]. LGE Co. has developed a digital TV system that displays HD (High definition) signal with the AR7TDMI CPU and the commercial RTOS[2]. This thesis made improvements on problems caused by porting embedded LiNUX in limited size memory (2 mega byte) instead of RTOS[3]. The advantages of changing to embedded LiNUX take away running OS royalty that needed to make TV sets[4].

• Journal of Digital Convergence
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• v.7 no.1
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• pp.125-136
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• 2009

SK Communications entered Korean instant messenger market as a late-mover in 2001 and its instant messenger service "NateOn" was placed in competition with Microsoft's "MSN Messenger", the leading service provider at the time. NateOn studied the nature of users accurately and gradually increased its market share through various services, and in September 2005, it succeeded in overtaking MSN as No.1 in the market. The success of NateOn is a case where a late-mover overcame the buddy-list network, a powerful competitive advantage, of the incumbent. By studying the changes in the instant messenger market of Korea, we try to examine the causes of NateOn's victory and MSN's loss. Through this, we wish to give implications for managers who endeavor to discover the internal and external strategies the leading business has to implement to remain ahead, and how a late-mover can overcome the lack of resources and capacity to leave a mark in the market.

• Journal of Digital Contents Society
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• v.14 no.2
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• pp.199-206
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• 2013

Various methods of data compression have been developed to handle data within limited storage capacity and limited transmission speed. Recompression technology, a technology most recent among them, is a technology that can embed data regardless of the information entropy of a data. Recompression technology separates original multimedia data in to blocks and embeds 0 or 1 according to whether each block is flipped or not. In this paper, this technology has been applied on audio files. And was able to implement reversible watermarking for audio files.

• Journal of Digital Convergence
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• v.3 no.1
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• pp.27-44
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• 2005

Nowadays, demand for human resource for the e-learning industry is rapidly increasing along with the expansion of e-learning market capacity. However. there are numerous difficulties in expansion and industrialization of e-learning due to insufficient supply of human resources to meet the demand. Therefore, the goal of this study is to present various policy directions that can supplement the supply or e-learning manpower. Overall contents of this study focus on presenting the long-term directions for fostering of human resources for e-learning industry. Among these, role of government policies for fostering of human resources for e-learning industry is being particularly emphasized because e-learning industry is still at its infant stage.

• ETRI Journal
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• v.28 no.3
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• pp.311-319
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• 2006

This paper presents a terminal-assisted frame-based packet reservation multiple access (TAF-PRMA) protocol, which optimizes random access control between heterogeneous traffic aiming at more efficient voice/data integrated services in dynamic reservation TDMA-based broadband access networks. In order to achieve a differentiated quality-of-service (QoS) guarantee for individual service plus maximal system resource utilization, TAF-PRMA independently controls the random access parameters such as the lengths of the access regions dedicated to respective service traffic and the corresponding permission probabilities, on a frame-by-frame basis. In addition, we have adopted a terminal-assisted random access mechanism where the voice terminal readjusts a global permission probability from the central controller in order to handle the 'fair access' issue resulting from distributed queuing problems inherent in the access network. Our extensive simulation results indicate that TAF-PRMA achieves significant improvements in terms of voice capacity, delay, and fairness over most of the existing medium access control (MAC) schemes for integrated services.

• Journal of Digital Contents Society
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• v.8 no.4
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• pp.425-430
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• 2007

Depends on the running dry of the radio resources for the next generation of wireless communication system the estimated possibilities of the visible light which used for the devices such as signal light, the electric display board, guide board and so on applied for the next generation wireless network is the topic to be explored in this paper. Since radiation efficiency utilization for the wireless network has its capacity to become a trend direction we will study also on its application as well as the technique standardization.

• Journal of The Korean Digital Architecture Interior Association
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• v.3 no.2
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• pp.47-54
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• 2003

A Steel plate shear wall can be used as one of the lateral force resistant elements in buildings. It have many advantages from a structural point of view such as ductility, energy absorption capacity and initial stiffness etc. In this study to grasp the behavior of steel plate shear wall considering material and geometrical non-linearity, the FEM analyses were carried out using ANSYS(ver. 5.6) program. The analysis results were fully discussed and compared with test results to verify the validity of analysis method. The object of this study is to find out analytically the elasto-plastic behavior of un-stiffened steel plate shear wall.

• Proceedings of the KIPE Conference
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• 2001.07a
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• pp.308-311
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• 2001

Most of the battery charger for electric powered forklift truck are controlled by the method of 3-phased constant current and constant voltage. However, these chargers have several disadvantages like a large charger capacity, and a short battery life time. This paper presents a digital type battery charger based on multi-mode control adding a constant power control and several assistant controls in the conventional control. The whole control system is performed by a low cost one-chip micro-controller and completely digitize. So we can get a high precision control and a good reliability.