• Journal of information and communication convergence engineering
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• v.12 no.2
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• pp.67-74
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• 2014

In multi-hop communication systems, two-way relaying is one of the solutions to mitigate the spectral efficiency loss caused by a half-duplex transmission. In this paper, a simple two-way relaying scheme is proposed for two-hop two-user multiple input multiple output (MIMO) systems. In the proposed system, a base station and a relay station (RS), both equipped with two antennas, form a point-to-point MIMO channel, while the RS and two single-antenna mobile users form a point-to-multipoint multiuser (MU)-MIMO channel. Numerical examples show that the proposed system achieves a significant sum rate gain as compared to a one-way relaying system as the distance between a relay and the two users decreases. We also show that although we can expand the proposed scheme to more than two users, its performance gain as compared to that of one-way relaying decreases with an increase in the number of users.

• The Korean Journal of Applied Statistics
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• v.23 no.6
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• pp.1201-1208
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• 2010

In teaching probability and statistics classes, we should increase efforts to develop examples that enhance teaching methodology in delivering more meaningful knowledge to students. Sports is one field that provides a variety of examples and World Cup Soccer events are a treasure house of many interesting problems. Teaching, using examples from this field, is an effective way to enhance the interest of students in probability and statistics because World Cup Soccer is a matter of national interest. In this paper, we have suggested several examples pertaining to counting the number of cases and computing probabilities. These examples are related to many issues such as possible scenarios in the preliminary round, victory points necessary for each participant to advance to the second round, and the issue of grouping teams. Based on a simulation using a statistical model, we have proposed a logical method for computing the probabilities of proceeding to the second round and winning the championship for each participant in the 2010 South Africa World Cup.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1984.10a
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• pp.25-27
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• 1984

Using LED sources, the system that performs optical logic function of the input data arrays will be presented. Sixteen possible functions of two binary data arrays, such as AND, OR, NOR and XOR are simply obtained in parallel by controlling LED switching mode. Experimental result and some examples of application will be given.

• Journal of Korean Institute of Industrial Engineers
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• v.36 no.2
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• pp.138-145
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• 2010

In this paper, we consider the information processing system, which organizes the collected data to meaningful information when the number of data collected from multiple sources reaches to a predetermined number, and performs any action by processing the collected data, or transmits to other devices or systems. We derive an analytical model to calculate the time until it takes to process information after starting to collect data. Therefore, in order to complete the processing data within certain time constraints, we develop some design criteria to control various parameters of the information processing system. Also, we analyze the discrete time model for packet switching networks considering data with no particular arrival nor drop pattern. We analyze the relationship between the number of required packets and average information processing time through numerical examples. By this, we show that the proposed model is able to design the system to be suitable for user's requirements being complementary the quality of information and the information processing time in the system with time constraints.

• International Journal of Computer Science & Network Security
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• v.21 no.8
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• pp.51-54
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• 2021

The article is devoted to the study of the features of administrative liability for offenses in the informational sphere, the definition of the concept and features. Based on the examples of implementation of instruments of European legislation into the national legal system and examples of national legal practice, the authors have identified the features of informational and legal sanctions aimed at restricting the rights of access of subjects to information, prohibiting them to disseminate certain information, restricting the rights to disseminate certain information, and suspending informational activities. It has been substantiated that the administrative liability for informational offenses as a protective legal institution is created to contribute to the solution of such acute problems of legal support of human and society interests in the new informational dimensions.

• The Journal of the Korea institute of electronic communication sciences
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• v.19 no.2
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• pp.403-408
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• 2024

Software development methods have continued to evolve in response to changes in the environment. Structural methodology, information engineering methodology, and object-oriented methodology are the major trends of this change. Each methodology has its own characteristics and advantages, and its applied fields are different. Engineers performing practical work are familiar with applying each methodology, but are not familiar with applying structural methodologies or information engineering methodologies in an integrated manner. Therefore, the maximum effect of the methodology cannot be obtained. With this in mind, we would like to organize and present examples of how to integrate and apply structural methodology and information engineering methodology to the target of each methodology.

• International Journal of Computer Science & Network Security
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• v.21 no.12
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• pp.41-44
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• 2021

This article proposes to consider the experience of using information and communication technologies in educational processes and social practices of Ukrainian universities. The history of the introduction of information and communication technologies in the development of the higher education system is considered, the system of organizing the information space of universities is investigated. The distinctive features of the structure of a single information space, as well as distance e-learning technologies are highlighted. Empirical material obtained in the course of sociological research is used to discuss specific examples of the use of ICT in universities.

• Proceedings of the Korean Geotechical Society Conference
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• 2000.03b
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• pp.297-302
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• 2000

This paper reports the application of GPS (Global Positioning System) technique into the geotechnical information system. Typical example of such application can be the database of logging data. Other examples can be found from the surveying for road work, excavation work, landslide mapping and image processing of slope face. This paper also reports the enhancement method of the accuracy. The results from this study confirms that GPS could be a powerful tool for the future geotechnical investigation works in Korea.

• Journal of the Korea Society of Computer and Information
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• v.22 no.8
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• pp.41-46
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• 2017

In this paper, we investigate the D2D Transmitter(Tx) and Receiver(Rx) pair assignment problem in the cellular system where D2D users share the uplink resource of the cellular system. Sharing the uplink resource of the cellular system may cause interference to the cellular system, though it is beneficial to improve the D2D user Capacity. Therefore, to protect the cellular users, D2D transmit power should be carefully controlled. In this work, we focus on optimal Tx-Rx assignment in such a way that the total transmit power of users is minimized. First, we consider the optimum Tx-Rx assignment in general and the corresponding complexity. Then, we propose an iterative D2D Tx-Rx assignment algorithm with low complexity that can minimize total transmit power of users. Finally, we present the numerical examples that show the complexity and the convergence to the unique transmit power level.

• Journal of the Korea Society of Computer and Information
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• v.20 no.7
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• pp.49-56
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• 2015

In this paper, we introduce recent cloud system security technologies categorizing them according to Reliability, Availability, Serviceability, Integrity, and Security (RASIS), terms that evaluate robustness of the computer system. Then we describe examples of security attacks and corresponding security technologies for each of them. We introduce security technologies based on Software Defined Network (SDN) for Reliability, security technologies based on hypervisor and virtualization for Availability, disaster restoration systems for Serviceability, authorization and access control technologies for Integrity, and encryption algorithms for Security. We believe that this paper provide wise view and necessary information for recent cloud system security technologies.