• The Journal of Korean Institute of Communications and Information Sciences
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• v.38A no.1
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• pp.58-67
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• 2013

In this paper, a mobile relay station(MRS) for vehicles with a beamforming antenna is considered to increase the reliability of a transmission link, especially for the MRS at cell boundary. Cell searching and direction-of-arrival(DoA) estimation methods for an MRS with a uniform linear array(ULA) are proposed for a multipath environment in OFDM-based cellular systems. Performances of the proposed methods(Method1 and Method2) are evaluated by computer simulation with the standard profile of IEEE 802.16e.

• Journal of Environmental Science International
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• v.19 no.2
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• pp.255-260
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• 2010

A stabilization/solidification (S/S) process for lead (Pb) contaminated soils was evaluated using waste cow bone containing apatite like compounds. Soil samples obtained form firing range were treated with waste cow bone. The effectiveness of stabilization was evaluated based on the Korean Standard Leaching Test (KSLT) and soil pH. The leached concentration reduced with increased in dose of waste cow bone. Overall, the KSLT results showed that Pb concentration in soils are significantly affected by amount of waste cow bone. When soil amended with 20 % of waste cow bone, less than 0.1 mg/kg was leached, and soil pH was increased from 6.5 to 8.4. Same results were obtained when finer waste cow bone was applied. The reachable concentration of Pb in soil showed in inversely proportional to solid/liquid ratio. Aging periods indicate improving mix design was applied. Relatively high lead concentrations was observed at the first 1 days, however leaching profile are reduced significantly over time for all mix designs.

• ETRI Journal
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• v.28 no.6
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• pp.721-731
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• 2006

A fast intra skip detection algorithm based on the ratedistortion (RD) cost for an inter frame (P-slices) is proposed for H.264/AVC video encoding. In the H.264/AVC coding standard, a robust rate-distortion optimization technique is used to select the best coding mode and reference frame for each macroblock (MB). There are three types of intra predictions according to profiles. These are $16{\times}16$ and $4{\times}4$ intra predictions for luminance and an $8{\times}8$ intra prediction for chroma. For the high profile, an $8{\times}8$ intra prediction has been added for luminance. The $4{\times}4$ prediction mode has 9 prediction directions with 4 directions for $16{\times}16$ and $8{\times}8$ luma, and $8{\times}8$ chrominance. In addition to the inter mode search procedure, an intra mode search causes a significant increase in the complexity and computational load for an inter frame. To reduce the computational load of the intra mode search at the inter frame, the RD costs of the neighborhood MBs for the current MB are used and we propose an adaptive thresholding scheme for the intra skip extraction. We verified the performance of the proposed scheme through comparative analysis of experimental results using joint model reference software. The overall encoding time was reduced up to 32% for the IPPP sequence type and 35% for the IBBPBBP sequence type.

• The Journal of Korean Physical Therapy
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• v.21 no.1
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• pp.41-48
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• 2009

Purpose: The examine the Reliability and Validity of the modified Emory Functional Ambulation Profile (mEFAP), Tinetti. Gait (TG), Timed Up & Go Tes t (TUG), Comfortable Gait Speed (CGS), Berg Balance Scale (BBS) in assessing gait function and balance in elderly person. Methods: The 45 community-dwelling subjects were participated in this study. Reliability was determined by intra-class correlation coefficient (ICC$_{3,1}$), Bland and Altman method (Standard Error of Measurement (SEM), Smallest Real Difference (SRD)). Results: Validity was examined by correlation the mEFAP, TG, TUG, CGS, BBS. The intra-rater reliability were High (ICC$_{3,1}$ : mEFAP=0.95, TG=0.96, TUG=0.94, CGS=0.96, BBS=0.92) and Absolute reliability were excellent (SEM: mEFAP=1.90, TG=0.21, TUG=0.28 CGS=0.25, BBS=0.52), (SRD: mEFAP=5.26, TG=0.58, TUG=0.77, CGS=0.69, BBS=1.44). There were significant correlations between assessment tool (r=.0.58$\sim$0.78, p<0.01) indicating good validity. Our results provide strong evidence that the assessment tool has good reliability, validity for assessing elderly person undergoing rehabilitation. Conclusion: The gait assessment tool is a useful scale for measuring walking function and recovery in elderly person.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.38 no.1
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• pp.69-78
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• 2001

MPEG-4 visual conformance standard specifies methods to verify whether bitstreams and decoders meet the requirements at the specified profile and level. The test of decoders can be divided into two parts: the static test and the dynamic test. The static test can be performed by examining the decoder output with that of a reference decoder. This paper proposes design methods of test bitstreams for static test of texture decoding, and shows the test results.

• Journal of Sasang Constitutional Medicine
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• v.29 no.1
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• pp.29-39
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• 2017

Objectives Facial features can be utilized as an indicator of Korean medical diagnosis. They are often measured by using the diagnostic device for an objective diagnosis. Accordingly, it is necessary to verify the reliability of the features which are obtained from the device for the accurate diagnosis. In this study, we attempt to evaluate the repeatability of facial feature variables using the Sasang Constitutional Analysis Tool(SCAT) for the Sasang Constitutional face diagnosis. Methods Facial pictures of two subjects were taken 24 times respectively for two days according to a standard guideline. In order to evaluate the repeatability, the coefficient of variation was calculated for the facial features extracted from frontal and profile images. Results The coefficient of variation was less than 10% in most of the facial features except the upper lip, trichion, and chins related features. Conclusions It was confirmed that the coefficient of variation was small in most of the features which enables the objective and reliable analysis of face. However, some features showed the low reliability because the location of facial landmarks related to them is ambiguous. In order to solve the problem, a clear basis for the location discussion is required.

• Transactions on Electrical and Electronic Materials
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• v.12 no.3
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• pp.93-97
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• 2011

In this paper, we discuss design considerations for an n-channel metal-oxide-semiconductor field-effect transistor (MOSFET) with a lateral asymmetric channel (LAC) doping profile. We employed a 0.35 ${\mu}M$ standard complementary MOSFET process for fabrication of the devices. The gates to the LAC doping overlap lengths were 0.5, 1.0, and 1.5 ${\mu}M$. The drain current ($I_{ON}$), transconductance ($g_m$), substrate current ($I_{SUB}$), drain to source leakage current ($I_{OFF}$), and channel-hot-electron (CHE) reliability characteristics were taken into account for optimum device design. The LAC devices with shorter overlap lengths demonstrated improved $I_{ON}$ and $g_m$ characteristics. On the other hand, the LAC devices with longer overlap lengths demonstrated improved CHE degradation and $I_{OFF}$ characteristics.

• ALGAE
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• v.32 no.3
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• pp.245-259
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• 2017

We report on the culture growth and stress-induced secondary carotenogenesis in a biotechnologically promising but largely unexplored chlorophyte Coelastrella rubescens strain Vinatzer/Innsbruck V 195. Changes in the cell morphometry, biomass accumulation, its carotenoid and fatty acid profiles were followed in the cultures supplemented with either inorganic ($CO_2$) or organic (sodium acetate) carbon on the background of low-pH stress. Collectively, the results of the study characterize C. rubescens as a biotechnologically promising, potentially double-purpose organism. It produces several secondary keto-carotenoids with a considerable proportion of astaxanthin and canthaxanthin. At the same time, the cell lipid fatty acid profile of this microalga is suitable for obtaining a high-quality biodiesel complying with the strictest EN14214 European standard.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.04a
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• pp.629-634
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• 2000

Generally, the accuracy of motion control systems is strongly influenced by both the mechanical characteristics and servo characteristics of feed drive systems. In the fed drive systems of machine tools that consist of mechanical parts and electrical parts, a torsional vibration is often generated because of its elastic elements in torque transmission. Especially, a torsional vibration caused by the elasticity of mechanical elements might deteriorate the quick movement of system and lead to shorten the life time of the mechanical transmission elements. So it is necessary to analyze the electromechanical system mathematically to optimize the dynamic characteristics of the feed drive system. In this paper, based on the simplifies feed drive system model, radius errors due to position gain mismatch and servo response characteristic have been developed and an optimal criterion for tuning the gain of speed controller is discussed. The proportional and integral parameter gain of the feed drive controller are optimal design variables for the gain tuning of PI speed controller. Through the optimization problem formulation, both proportional and integral parameter are optimally tuned so as to compensate the radius errors by using the genetic algorithm. As a result, higher performance on circular profile tests has been achieved than the one with standard parameters.

• Architectural research
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• v.16 no.1
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• pp.17-25
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• 2014

This research is to restructure the public assessment of housing management in a standardized fashion, and a self-administered questionnaire survey was employed for data collection and analysis. In doing so, all the assessment tools nationwide were identified and assembled to extract the items included in the survey form. The survey form was mailed out to local officers in charge of housing management and professional housing managers in the nation, and the responses were statistically analyzed in order to structure the standard assessment tool of housing management. This research classified 3 main areas (General Maintenance, Operation and Community Living) in evaluating the housing management performance, and identified 35 essential items and 52 optional items. The 35 essential items were drawn from the 16 categories of the 3 areas (11 items of 5 categories for General Maintenance, 7 items of 4 categories for Operation, and 17 items of 7 categories for Community Living), and the rest 52 optional items were from the 16 categories of the 3 areas (24 items of 7 categories for General Maintenance, 26 items of 7 categories for Operation, and 2 items of 2 categories for Community Living). While all the items in the research are quantifiable, it's suggested that qualitative measurements be complementarily utilized in the assessment not only to explore the best practices of housing management but also to refine and modify the standardized tool in response to various environmental changes. As the public assessment of housing management is context-sensitive and critically related to local housing profile, the continuous implementation of the assessment will facilitate shifting the housing paradigm from production and consumption to management and reproduction.