• Journal of Computing Science and Engineering
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• v.7 no.3
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• pp.168-176
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• 2013

Long-term evolution (LTE) is emerging as a major candidate for 4G cellular networks to satisfy the increasing demands for mobile broadband services, particularly multimedia delivery. Multiple-input multiple-output (MIMO) technology combined with orthogonal frequency division multiple access and more efficient modulation/coding schemes (MCS) are key physical layer technologies in LTE networks. However, in order to fully utilize the benefits of the advances in physical layer technologies, the MIMO configuration and MCS need to be dynamically adjusted to derive the promised gains of 4G at the application level. This paper provides a performance evaluation of video traffic with variations in the physical layer transmission parameters to suit the varying channel conditions. A quantitative analysis is provided using the perceived video quality as a video quality measure (evaluated using no-reference blocking and blurring metrics), as well as transmission delay. Experiments are performed to measure the performance with changes in modulation and code rates in poor and good channel conditions. We discuss how an adaptive scheme can optimize the performance over a varying channel.

• The Journal of the Acoustical Society of Korea
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• v.31 no.4
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• pp.225-234
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• 2012

The anechoic chamber is essential tool to measure the various acoustic parameters with high precision. The chamber provides the climate controlled indoor environments but requires the dedicated room at a great cost in order to isolate and absorb sound field. Provided the purpose of the chamber is specific to the experiments of sound localization, the performance requirements excluding free field can be alleviated for cost effective solution. This paper designs low cost and profile anechoic chamber based on acoustic pyramids and evaluates the performance specified by the Annex of ISO 3745. Data analysis is employed to measure the free and hemi-free field performance over five straight paths for working areas and four paths for non-working areas. The identical two measurement campaigns were conducted for free and hemi-free field chamber which is easily interchangeable by simple labor in this chamber design. In the working area with conventional speaker, the results of these analyses demonstrate that lab-designed anechoic chamber is in conformance with ISO 3745 for 250 Hz - 16 kHz one-third octave band at free field chamber and for 1 kHz - 16 kHz one-third octave band at hemi-free field chamber.

• Journal of Biomedical Engineering Research
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• v.38 no.3
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• pp.89-94
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• 2017

In order to improve national competitiveness through technological research and development, the government puts in R&D budget every year and manages to improve the R&D results. Accordingly, various R&D project management methods have applied for successful advancement of technology and product. TRL is a measurement system developed by NASA to assess the maturity of technology since the 1970s. To apply medical device, the characteristics such as regulation, clinical trials are considered as a significant influence. In this study, we would like to derive PMI(performance measures index) for medical device R&D projects by using TRL and stage-gate model. As a result of this study, it is possible to use the PMI for decision making and evaluation in the R&D projects and believed that the objectivity can be ensured by the approval or certification of regulatory authority.

• Journal of the Korean Society of Systems Engineering
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• v.10 no.2
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• pp.59-69
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• 2014

In the bidding stage of turn-key based plant construction contracts, owners provide design and performance basis for contractors instead of giving design drawing. To win the bid for a plant construction, the contractors should be obliged to satisfy and ensure owners'requirements such as design and performance basis in a plant construction project, In other words, owners imposes technical risk of the design to the contractors by specifying responsibility for the analysis and verification of the plant construction. Thus, it is very important that contracters make accurate and realistic basic design plan in a short period of time. To deal with such a situation, we propose a systems engineering approach for the analysis and management of the technical risk. Specifically, we first: 1) Analyzes technical risk related with the plant design information for the bidders, followed by 2) Developing stakeholder requirements for the basic engineering design, and 3) System requirements for dealing with technical risk. Also, in this paper, we proposed converting method from MOE(Measure of Effectiveness) to MOP(Measure of Performance) in the risk analysis. To show the effectiveness of the proposed method, we carried out a case study.

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.3
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• pp.473-478
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• 2020

The communication between train and it's moving environments is considered as a necessity factor to support accuracy and safety for operation of train. Communication structure and performance between sensor and train used to measure and monitor between train and it's moving environments is required in operation of the train. In this paper, railway sensor network based on LTE-R is described and analyzed for moving train to support effective measure operation and environment data from various sensor devices located through railway and then transfer the data to data control center. Finally, implementation requirement for railway sensor network is suggested.

• The Transactions of the Korea Information Processing Society
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• v.3 no.5
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• pp.1215-1228
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• 1996

The purpose of benchmark program is to measure the performance of a computer system. The performance of a computer system is determined by the amount of execution time of user application programs. Thus, it is assumed that a benchmark program must have the same features with user application programs to test. In this paper, we have designed and implemented CMFstone which is consisted of Chaustone, Mchaustone and Fhsstone. After applied the CMFstone, designed and implemented in this paper, to the real situations, the results of comparison show that CMFstone is similar to geometric mean of other benchmarks results. Thus, we have concluded that CMFstone is good enough to measure the performance of a computer system.

• IEMEK Journal of Embedded Systems and Applications
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• v.12 no.4
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• pp.231-238
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• 2017

Detecting small infrared targets from the low-SCR images at a long distance is very hard. The previous Local Contrast Method (LCM) algorithm based on the human visual system shows a superior performance of detecting small targets by a background suppression technique through local contrast measure. However, its slow processing speed due to the heavy multi-scale processing overhead is not suitable to a variety of real-time applications. This paper presents a lightweight real-time small target detection algorithm, called by the Improved Selective Local Contrast Method (ISLCM), to reduce the scale-invariant computational overhead. The proposed ISLCM applies the improved local contrast measure to the predicted selective region so that it may have a comparable detection performance as the previous LCM while guaranteeing low scale-invariant computational load by exploiting both adaptive scale estimation and small target feature feasibility. Experimental results show that the proposed algorithm can reduce its computational overhead considerably while maintaining its detection performance compared with the previous LCM.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.27 no.3
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• pp.97-105
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• 2004

The purpose of this study is to design and implement web-based quality cost management system to measure the performance of quality improvement activities in the business firms. The designed web-based quality cost management system which is also known as WQCMS (Web-based Q-Cost Management System) utilized newly classified objective performance indicator items to measure quality related activities. Well-classified performance measurement Indicator item lists which are played key role in the system was researched and standardized according to size and business categories of enterprise. Its code standards are based from fundamental PAF Model. Developed WQCMS have ability to collect and analyze quality data generated from various different departments in the inside or outside of the enterprise without any limitations, if end-users are able to access wide area network. It provides the capability to integrate quality information from database and to generate various easy analysis reports to management's needs using built-in analysis tool modules with real-time. The proposed system was developed using Microsofi's .Net technology, ASP.NET and MS-SQL Server 2000. By web-enabling Q-cost management system, the effectiveness of the system management and utilization was realized by easiness of information Integration and economical efficiency.

• Journal of applied mathematics & informatics
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• v.30 no.5_6
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• pp.699-717
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• 2012

In this paper, we deal with the robust mixed $H_2/H_{\infty}$ guaranteed-cost control problem involving uncertain neutral stochastic distributed delay systems. More precisely, the aim of this problem is to design a robust mixed $H_2/H_{\infty}$ guaranteed-cost controller such that the close-loop system is stochastic mean-square exponentially stable, and an $H_2$ performance measure upper bound is guaranteed, for a prescribed $H_{\infty}$ attenuation level ${\gamma}$. Therefore, the fast convergence can be fulfilled and the proposed controller is more appealing in engineering practice. Based on the Lyapunov-Krasovskii functional theory, new delay-dependent sufficient criteria are proposed to guarantee the existence of a desired robust mixed $H_2/H_{\infty}$ guaranteed cost controller, which are derived in terms of linear matrix inequalities(LMIs). Furthermore, the design problem of the optimal robust mixed $H_2/H_{\infty}$ guaranteed cost controller, which minimized an $H_2$ performance measure upper bound, is transformed into a convex optimization problem with LMIs constraints. Finally, two simulation examples illustrate the design procedure and verify the expected control performance.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.42 no.1
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• pp.46-49
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• 2017

In this letter, we investigate the impact of image downsampling on the performance of background subtraction in Full-HD soccer videos. To this end, we evaluated the performance of background subtraction in terms of both accuracy and computational time. Furthermore, for the sake of completeness, we used two different background subtraction methods under the same experimental setup. For the quantitative comparison, we employed the F-measure and FPS(frames per second). We believe that this study serves as a practically useful benchmark for researchers and practitioners in developing a fast background subtraction algorithm adopted for building real-time intelligent soccer video analysis systems.