• Smart Structures and Systems
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• v.13 no.6
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• pp.901-925
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• 2014

The reliability of a Bridge management System depends on the quality of visual inspection and the reliable estimation of bridge condition rating. However, the current practices of visual inspection have been identified with several limitations, such as: they are time-consuming, provide incomplete information, and their reliance on inspectors' experience. To overcome such limitations, this paper presents an approach of automating the prediction of condition rating for bridges based on digital image analysis. The proposed methodology encompasses image acquisition, development of 3D visualization model, image processing, and condition rating model. Under this method, scaling defect in concrete bridge components is considered as a candidate defect and the guidelines in the Ontario Structure Inspection Manual (OSIM) have been adopted for developing and testing the proposed method. The automated algorithms for scaling depth prediction and mapping of condition ratings are based on training of back propagation neural networks. The result of developed models showed better prediction capability of condition rating over the existing methods such as, Naïve Bayes Classifiers and Bagged Decision Tree.

• Journal of the Earthquake Engineering Society of Korea
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• v.20 no.5
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• pp.331-340
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• 2016

It is important to select proper ground motions for obtaining accurate results from response history analyses. The purpose of this study is to propose an accurate and efficient method that does not require excessive computation for selecting and scaling ground motions to match target response spectrum mean and variance. The proposed method is conceptually simple and straightforward, and it does not use a simulation algorithm that requires a sophisticated subroutine program. In this method, the desired number of ground motions are sequentially scaled and selected from a ground motion library. The proposed method gives the best selection results using Sum of Square Error and has the smallest value(=0.14). Also, The accuracy and consistency of the proposed method are verified by comparing the selection results of the proposed method with those of existing methods.

• Journal of Periodontal and Implant Science
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• v.44 no.3
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• pp.118-125
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• 2014

Purpose: The present split mouth study evaluates the effect of nonsurgical periodontal treatment on the gingival crevicular fluid (GCF) leptin level in chronic periodontitis. Methods: Ninety sites from 30 nonobese chronic periodontitis patients were selected and divided as follows: group I, 30 healthy sites receiving no treatment; group II, 30 periodontitis sites receiving scaling and root planing (SRP); and group III, 30 periodontitis sites receiving SRP with tetracycline local drug delivery. At baseline, after GCF sampling and clinical parameter recording, the assigned treatment was performed for the study groups. During recall visits, GCF sampling followed by clinical parameter recording was done for groups II and III. Results: Reductions in the probing depth and the clinical attachment level (CAL) were highly significant at different time intervals (except between day 0 and 45) in both groups II and III. Upon comparison, group III showed significant gain in CAL between day 0 and 15 and between day 0 and 45. After treatment, the reduction in the GCF leptin level was more significant in group III than in group II at day 15 but re-elevated almost to the pretreatment levels at day 45. Conclusions: Nonsurgical periodontal therapies were not effective in maintaining stable reduction in the GCF leptin level during the study period.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.81.2-81.2
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• 2016

Many signals in the nature have power-law behaviors, namely they are "scale-free". The method of detrended fluctuation analysis (DFA), as one of the popular methods (e.g., Rescaled range analysis and Spectral analysis) for determining scale-free nature of time series, has a very important advantage that the DFA can be applied to both stationary and non-stationary signals. The analysis of time series using the DFA has been broadly used in physiology, finance, hydrology, meteorology, geology, and so on. We performed the DFA of 16 Spaceweather HMI Active Region Patch (SHARP) parameters for 38 HMI Active Region Patches (HARPs) obtained by Solar Dynamics Observatory (SDO) from May 2010 to June 2014. The main results from this study are as follows. (1) The most of the time series data are non-stationary. (2) The DFA scaling exponents of "mean vertical current density" for 38 HARPs have a negative correlation coefficient (-0.41) with flare index. (3) The DFA scaling exponents of parameters such as "Sum of the absolute value of net currents per polarity", "Absolute value of the net current helicity", and "Mean photospheric excess magnetic energy density" for the most active HARPs having more than 10 major flares, have positive correlation coefficients (0.64, 0.59, and 0.53, respectively) with the ratio of "the number of CMEs associated with major flares" to "the number of major flares". Physical interpretations on our results will be discussed.

• The KIPS Transactions:PartA
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• v.16A no.1
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• pp.27-34
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• 2009

Recently, power saving with high performance is one of the hot issues in the mobile systems. Various technologies are introduced to achieve low-power processors, which include sub-micron semiconductor fabrication, voltage scaling, speed scaling and etc. In this paper, we introduce a new method that reduces of energy loss at the data cache. Our methods take the benefits in terms of speed and energy loss using selective way precharging of way prediction with concurrent way selecting. By the simulation results, our method achieves 10.2% energy saving compared to the way prediction method, and 56.4% energy saving compared to the common data cache structure.

• Journal of dental hygiene science
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• v.2 no.2
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• pp.69-73
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• 2002

The purpose of this study was to obtain baseline data for developing oral health education program. The questionaire about oral health knowledge and behaviors were given to 1419, 12 year-old children who lived in Seongnam City. The results were obtained as follows; 1) Of respondents, 46.2% visited dental offices within a year. And 33% of them were for the purpose of routine examinations and prevention. 2) 67.1% of them exhibited toothbrushing before bedtime and only 11.3% and 8.9% of them toothbrushed after between-meal intake and lunch. 3) 47.7% of them experienced dental health education programs and 72.3% of the programs had been during elementary school days. 4) 56.2% of them chose dentifrices without standards and 21.6% of them considered the presence of fluoride. 5) Of respondents, 57.4% and 46.4% knew the importances of toothbrushing and dietary pattern. But only 18.7% and 8.5% of them knew the methods of using fluoride and scaling. 6) 33% of them replied negatively to the probabilities of preventing dental caries. 7) Also, it is necessary to expand the oral health education programs for 12 year-old children in Seongnam City and include the annual screening dental examination, toothbrushing, dentifrice selection, using fluoride and scaling.

• Journal of Fisheries and Marine Sciences Education
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• v.29 no.2
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• pp.526-536
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• 2017

This study intended to understand similarity of image between games and position of image attribute perceived by consumers according to the games of marine sports using MDS (Multidimensional Scaling). Through the foregoing, this study aims to provide preliminary data for establishing marketing strategies for games of marine sports by accurately understanding images of marines sports perceived by consumers. For survey targets, this study selected students of K University located in Gyeonggi-do as a population, and extracted samples using convenience sampling out of non-probability sampling methods targeting 200 students who showed intention of participation in this study, and total 188 sheets of questionnaire were used as final data excepting 12 sheets that are filled up unfaithfully or considered unreliable. For data processing, this study conducted Frequency Analysis, Descriptive Statistical Analysis, Reliability Analysis, MDS (Multidimensional Scaling) and Multiple Regression Analysis, and study results show that water ski and wakeboard(.602) have the most similar image attribute, indicating that image attributes of scuba diving and water ski(2.031) are positioned farthest with each other. As for image attribute, image attribute of water ski has appearance and progressiveness, windsurfing has an image attribute of positive, scuba diving has an image attribute of negation, and marin rafting has an image attribute of friendliness.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.1
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• pp.259-264
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• 2006

It is well known that the uncertainty of the covariance parameters of the process noise (Q) and the observation errors (R) has a significant impact on Kalman filtering performance. Q and R influence the weight that the filter applies between the existing process information and the latest measurements. Errors in any of them may result in the filter being suboptimal or even cause it to diverge. The conventional way of determining Q and R requires good a priori knowledge of the process noises and measurement errors, which normally comes from intensive empirical analysis. Many adaptive methods have been developed to overcome the conventional Kalman filter's limitations. Starting from covariance matching principles, an innovative adaptive process noise scaling algorithm has been proposed in this paper. Without artificial or empirical parameters to be set, the proposed adaptive mechanism drives the filter autonomously to the optimal mode. The proposed algorithm has been tested using road test data, showing significant improvements to filtering performance.

• KIPS Transactions on Computer and Communication Systems
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• v.2 no.8
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• pp.343-348
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• 2013

We proposes a power-aware fixed-priority real-time scheduling algorithm for multimedia service, called static voltage scaling algorithm with multi-granularity resource reservation (STATIC-MULTIRSV). The multi-granularity resource reservation was introduced to deliver higher system utilization and better temporal isolation than the traditional approaches in [2]. Based on this, our STATIC-MULTIRSV is designed to reduce the power consumptions while guaranteeing that all I-frames of each video stream meet their deadlines. We implemented the proposed algorithm on top of ChronOS Real-time Linux [6]. We experimentally compared STATIC-MULTIRSV with other existing methods which showed that STATIC-MULTIRSV reduce power consumption by maximum 15% compared to its experimental counterparts.

• Korean Journal of Ecology and Environment
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• v.54 no.3
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• pp.221-228
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• 2021

Recently, environmental DNA (eDNA)-based metabarcoding approaches have been proposed to evaluate the status of freshwater ecosystems owing to various advantages, including fast and easy sampling and minimal habitat disruption from sampling. Therefore, as a case study, we applied eDNA metabarcoding techniques to evaluate the effects of an abandoned mine land located near a headwater stream of Nakdonggang River, South Korea, by examining benthic macroinvertebrate diversity and compared the results with those obtained using the traditional Surber-net sampling method. The number of genera was higher in Surber-net sampling (29) than in the eDNA analysis (20). The genus richness tended to decrease from headwater to downstream in eDNA analysis, whereas richness tended to decrease at sites with acid-sulfated sediment areas using Surber-net sampling. Through cluster analysis and non-metric multidimensional scaling, the sampling sites were differentiated into two parts: acid-sulfated and other sites using Surber-net sampling, whereas they were grouped into the two lowest downstream and other sites using eDNA sampling. To evaluate freshwater ecosystems using eDNA analysis in practical applications, it is necessary to constantly upgrade the methodologies and compare the data with field survey methods.