• Journal of Positioning, Navigation, and Timing
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• v.7 no.4
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• pp.189-203
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• 2018

In this paper, a Software Defined Radio (SDR) architecture was designed and implemented for rapid prototyping of GNSS receiver. The proposed SDR can receive various GNSS and direct sequence spread spectrum (DSSS) signals without software modification by expanded input parameters containing information of the desired signal. Input parameters include code information, center frequency, message format, etc. To receive various signal by parameter controlling, a correlator, a data bit extractor and a receiver channel were designed considering the expanded input parameters. In navigation signal processing, pseudorange was measured based on Coordinated Universal Time (UTC) and appropriate navigation message decoder was selected by message format of input parameter so that receiver position can be calculated even if SDR is set up various GNSS combination. To validate the proposed SDR, the software was implemented using C++, CUDA C based on GPU and USRP. Experimentation has confirmed that changing the input parameters allows GPS, GLONASS, and BDS satellite signals to be received. The precision of the position from implemented SDR were measured below 5 m (Circular Error Probability; CEP) for all scenarios. This means that the implemented SDR operated normally. The implemented SDR will be used in a variety of fields by allowing prototyping of various GNSS signal only by changing input parameters.

• Journal of Korea Society of Digital Industry and Information Management
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• v.9 no.2
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• pp.81-87
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• 2013

In this paper, we present an implementation of Long Term Evolution (LTE) Uplink (UL) system on a Software Defined Radio (SDR) platform using a conventional Personal Computer (PC), which adopts Graphic Processing Units (GPU) and Universal Software Radio Peripheral2 (USRP2) with URSP Hardware Driver (UHD) for SDR software modem and Radio Frequency (RF) transceiver, respectively. We have adopted UHD because UHD provides flexibility in the design of transceiver chain. Also, Cognitive Radio (CR) engine have been implemented by using libraries from UHD. Meanwhile, we have implemented the software modem in our system on GPU which is suitable for parallel computing due to its powerful Arithmetic and Logic Units (ALUs). From our experiment tests, we have measured the total processing time for a single frame of both transmit and receive LTE UL data to find that it takes about 5.00ms and 6.78ms for transmit and receive, respectively. It particularly means that the implemented system is capable of real-time processing of all the baseband signal processing algorithms required for LTE UL system.

• Journal of The Korean Association of Information Education
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• v.22 no.6
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• pp.701-710
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• 2018

In the 4th Industrial Revolution, it is a time when all the devices and people interact to create new added value. Software education is necessary in elementary school because what is more important is software. However, until now there is a lack of teaching and learning methods for software education in elementary school. In this paper, IDOL model is proposed as a method to solve this problem. statements for elementary students. The idol model is learning through observe, to implement, to diversify. In the implementation, the elementary students are to make it quickly, In the diversification, it is variously changing the things that have been made, and observation how the changed things are different. A model is verified by a group of experts consisting of elementary school teachers.

• Proceedings of the IEEK Conference
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• 2003.07a
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• pp.422-425
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• 2003

Software reconfigurable radio will give future users a number of benefits like global roaming, multi mode, multi band, and multi standard. It will also offer complete programmability and reconfigurability to both multi mode and multi functional communication terminal and network nodes. This configuration will be implemented by application of different combination of radio configurable software. In this paper, It proposes the algorithm needed for reconfiguration with basic explanation of the software download. A description of an implementation such reconfiguration processes as partial download and full download and critical and non-critical download installation using the registration table in included.

• International Journal of Computer Science & Network Security
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• v.21 no.2
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• pp.130-141
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• 2021

This paper is in the intersection of software engineering and system engineering, two intimately intertwined disciplines. A dominating theme in this paper is the integral conceptualization of systems at large, as well as an underlying concern with software systems. In the software development life cycle, challenges still exist in translating requirements into a design artifact and then into an implementation (e.g., coding), then validating the results. From our perspective, software engineering requires an integrating paradigm toward a unified modeling orientation. Many methodologies, languages, and tools exist for facilitating system development processes. This paper is a venture into project development. To focus the materials, we concentrate on Harel's novel (and classic) development environment, which integrates a scenario-based engineering object orientation and statecharts through developing a railcar system. The railcar system is used as a detailed sample of translating requirements into a design artifact and then into an implementation, then validating the result. The project is re-cased as a single integrated modeling endeavor to be contrasted with the scenario and statecharts' development. The result of this scheme is an enriched understanding through experimenting with and contrasting various development methods of software projects.

• The Journal of Information Technology and Database
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• v.8 no.2
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• pp.137-159
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• 2001

This study provides a thorough methodology for IT Investment evaluation. A software tool to support the evaluation process was introduced along with a case study. The software supports the methodology that consists of 7 phases : Target analysis, ldentifying IT measures, Measuring IT impact, Assessing business value, Analyzing the decree of realization, Cost-benefit analysis, and Reporting. The case study showed that the software (CAFA) was a very useful tool supporting both decision-making and post-implementation reviews of IT investment.

• Journal of Satellite, Information and Communications
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• v.4 no.1
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• pp.8-13
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• 2009

Software-Based GNSS Simulation Tool is being developed by ETRI as a part of development of software-based GNSS Test & Evaluation Facility which will provide test and evaluation environment for various software level application and navigation algorithm in GNSS. The simulation tool will provide digitized GNSS signal generator and receiver including GPS and Galileo. The detailed design and module implementation for the Software GNSS signal generation and signal processing simulation tool and its modular implementation is presented in this paper.

• IEMEK Journal of Embedded Systems and Applications
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• v.7 no.2
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• pp.113-120
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• 2012

In this paper we describe the integrated development environment for embedded software education. Our environment uses a cheap and widely available portable game console, Nintendo DS-lite. We have integrated open source development tools, and have implemented download shell, remote debugger. The results are all open source, and were used for university class for real embedded software education.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2004.11a
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• pp.254-254
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• 2004

• Journal of Institute of Control, Robotics and Systems
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• v.4 no.1
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• pp.113-122
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• 1998

This paper presents an implementation method of Profibus interface software using FMS(Fieldbus Message Specification). The Profibus interface software is implemented on PC which is widely used as an industrial computer as well as a commercial embedded controller called IUC(Intelligent Universal Controller). In order to enable the Profibus interface software to handle many application tasks and communication services, two kinds of real-time/multi-tasking operating system, OS-9 and CTask, are utilized. We also develop an experimental model of Profibus-based automation system, and evaluate the performance of the Profibus network. Through experiments, the user layer level message latency is measured with respect to the change of message length, message generation interval and TRT(Target Rotation Time). The results of experiment are compared with those of a simulation model which comprises only the physical and data link layers of Profibus. The results of this study shows that the message latency in the user layer level occupies fairly a large part of the total message latency.