• Journal of the Korean Society for Nondestructive Testing
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• v.25 no.1
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• pp.1-8
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• 2005

This paper presents the experimental results measured by photoelastic 4-step phase shifting method for the isochromatic fringe distribution in a TV glass panel. In the conventional photoelastic method, the isochromatic fringe orders are measured manually point by point. The 4-step phase shifting method uses four images obtained from a circular polariscope by rotating the analyzer to $0^{\circ},\;45^{\circ},\;90^{\circ}$, and $135^{\circ}$. In order to use the 4-step phase shifting method, the elements of a polariscope should be aligned to isoclinic direction at a point and/or along a line where isochromatic fringe distribution is measured. Experimental results obtained from the 4-step phase shifting method are compared with those measured by the Senarmont compensation method. Both results are well agreed. Then, isochromatic fringe distributions in the TV glass panel that is heat-treated before and after are compared. Maximum and minimum isochromatic fringe orders in the TV glass panel with before- and after-heat treatment are changed approximately two times.

• Korean Journal of Acupuncture
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• v.29 no.1
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• pp.23-36
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• 2012

Objectives : This study was conducted to investigate effective treatment point selection method using oppressive pain in acupoints as elementary attempt for standard methodology of clinical acupuncture studies. Methods : Twenty seven subjects with hypertension or within prehypertension category - systolic and diastolic blood pressure (BP) over 120/80mmHg - were divided into two groups, oppressive pain point treatment group and oppressive painless point treatment group. In oppressive pain point treatment group, single point acupuncture (SPA) was conducted for 16 sessions during 8 weeks on most oppressive painful point among 6 selected acupuncture points used in previous trials and clinic. As a SPA intervention, 15 minutes with deqi sensation- elevating manipulation was conducted on the treatment acupoint. Same process was conducted in oppressive painless point treatment group on most oppressive painless point with subject blinding. Results : Significant reduction was observed in both systolic and diastolic BP after short time intervention (15.5/8.8 mmHg, 10.7/7.1 mmHg, P<0.05, respectively at 1 week) and maintained for 8 weeks intervention period in all groups (12.8/8.0 mmHg, 19.4/12.6 mmHg, P<0.05, respectively). No significant difference of BP change between oppressive pain point treatment group (N=10) and oppressive painless point treatment group (N=9) was observed during 8 weeks study period. Conclusions : SPA treatment as used in this pilot study was effective for lowering BP in mild hypertensive population, but oppressive pain in acupoint had no effect on treatment. This present result suggests the possibility of SPA for hypertension treatment regardless of oppressive pain.

• Journal of the Institute of Electronics and Information Engineers
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• v.49 no.12
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• pp.124-130
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• 2012

In this paper, we propose a feature point selection method for MPEG CDVS CE-7 which is processing on International Standard task. Among a large number of extracted feature points, more important feature points which is used in image matching should be selected for the compactness of image descriptor. The proposed method is that remove the feature point in the extraction phase which is filtered by nearest neighbor distance ratio matching in the matching phase. We can avoid the waste of the feature point and employ additional feature points by the proposed method. The experimental results show that our proposed method can obtain true positive rate improvement about 2.3% in pair-wise matching test compared with Test Model.

• Advances in concrete construction
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• v.1 no.4
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• pp.319-340
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• 2013

This paper presents a comparative study on the double-K fracture parameters of concrete obtained using four existing analytical methods such as Gauss-Chebyshev integral method, simplified Green's function method, weight function method and simplified equivalent cohesive force method. Two specimen geometries: three point bend test and compact tension specimen for sizes 100-500 mm at initial notch length to depth ratios 0.25 and 0.4 are used for the comparative study. The required input parameters for determining the double-K fracture parameters are derived from the developed fictitious crack model. It is found that the cohesive toughness and initial cracking toughness determined using weight function method and simplified equivalent cohesive force method agree well with those obtained using Gauss-Chebyshev integral method whereas these fracture parameters determined using simplified Green's function method deviates more than by 11% and 20% respectively as compared with those obtained using Gauss-Chebyshev integral method. It is also shown that all the fracture parameters related with double-K model are size dependent.

• Korean Journal of Remote Sensing
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• v.35 no.6_1
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• pp.973-985
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• 2019

In this paper, we propose a method to separate the ground and building areas and generate building models automatically through planarity analysis using UAV (Unmanned Aerial Vehicle) based point cloud. In this study, proposed method includes five steps. In the first step, the planes of the point cloud were extracted by analyzing the planarity of the input point cloud. In the second step, the extracted planes were analyzed to find a plane corresponding to the ground surface. Then, the points corresponding to the plane were removed from the point cloud. In the third step, we generate ortho-projected image from the point cloud ground surface removed. In the fourth step, the outline of each object was extracted from the ortho-projected image. Then, the non-building area was removed using the area, area / length ratio. Finally, the building's outer points were constructed using the building's ground height and the building's height. Then, 3D building models were created. In order to verify the proposed method, we used point clouds made using the UAV images. Through experiments, we confirmed that the 3D models of the building were generated automatically.

• Journal of the Korean Chemical Society
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• v.59 no.5
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• pp.407-412
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• 2015

A preconcentration procedure for determination of palladium by laser thermal lens spectrometry (TLS) is proposed. It is based on cloud point extraction of palladium(II) ions as 2-(3,5-dichloro-2-pyridylazo)-5-dimethylaminoaniline (3,5-diCl-PADMA) complexes using octylphenoxypolyethoxyethanol (Triton X-114) as surfactant. The effects of various experimental conditions such as pH, concentration of ligand and surfactant, equilibration temperature and time on cloud point extraction were studied. Under the optimized conditions, the calibration graph was linear in the range of 0.15~6 ng mL⁻¹, and the detection limit was 0.04 ng mL⁻¹ with an enrichment factor of 22. The sensitivity was enhanced by 846 times when compared with the conventional spectrophotometric method. The recovery of palladium was in the range of 96.6%~104.0%. The proposed method was applied to the determination of palladium in water samples.

• Journal of the Korean Data and Information Science Society
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• v.20 no.1
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• pp.1-9
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• 2009

Let us consider that the variance function in regression model has a discontinuity/change point at unknown location. Yu and Jones (2004) proposed the local polynomial fit to estimate the log-variance function which break the positivity of the variance. Using the local polynomial fit, Huh (2008) estimate the discontinuity point of the log-variance function. We propose a test for the existence of a discontinuity point in the log-variance function with the estimated jump size in Huh (2008). The proposed method is based on the asymptotic distribution of the estimated jump size. Numerical works demonstrate the performance of the method.

• Journal of the Semiconductor & Display Technology
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• v.15 no.4
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• pp.61-66
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• 2016

This paper presents the implementation for a network structure of railway cars using a point to point communication. Most of network's representative specifications for a train are the FIP (Field Bus), MVB (Multifunction Vehicle Bus), CAN and WTB (Wire Train Bus) which is used by ALSOM, SIEMENS and BOMBADIER as major in this field. These networks in a physical layer use a multi-drop method, connected from $1^{st}$ car to $n^{th}$ car of a train through a cable without any extra services such as an electric part, amplifier. However waveforms which is passed through a long cable in the multi-drop are distorted by a capacitance or resistance of the cable or environments. Also since using a cable connected directly from $1^{st}$ car to $n^{th}$ car, if over two trains make double head, it isn't easy to distinguish ID for each railway cars. So by using the point to point network per each car, it is able to reduce a distortion. Also since reducing distortion, this communication speed can be been higher and transmit and receive any packets more stably. Using proposed token in a packet, this can make ID per each railway car automatically. Finally experimental results show the good performance and effectiveness of the proposed method.

• Journal of the Korean Vacuum Society
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• v.17 no.6
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• pp.487-494
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• 2008

The numerical simulation of point-to-plane discharge of nitrogen at medium pressure has been achieved by a quasi-2d numerical model. In the model, we calculate the distributions of electric charges which are varying as temporal and space and determine the electric field depending on space charge distribution by solving Poisson's equation. The continuity equations are treated numerically by using FCT (Flux-Corrected Transport) Algorithm and FEM (Finite Element Method). The numerical simulation results make us to understand the physical characteristics of nitrogen discharge at 50 torr. The comparison with experimental results[1] shows a good qualitative agreement.

• 한국정보통신설비학회:학술대회논문집
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• 2005.08a
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• pp.141-145
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• 2005

In this paper, UWB system did research about effect that interference effect with neighborhood single equipment or nearby group equipment gets In DMB service. 2.6425GHz satellite digital multimedia broadcasting service(SDMB) that electric wave interference special quality is contiguity frequency-band including interference of signal by unnecessary radiation level that is radiated in UWB system, and 3.4125GHz broadcasting relay net that is In-band frequency-band and interference effect degree that get in service did comparative analysis. SDMB system was BER $1{\times}10^{-4}$ that interference effect happens from 6.5m point and broadcasting signal reception is possible at 4m point. Also, it was BER $1{\times}10^{-4}$ that interference effect begins to happen from 5.0m point about center frequency 3.4126GHz and broadcasting signal reception is possible at 2m point. And, confirmed that UWB system of impulse method is less interference effect about 2 dB than UWB system of OFDM method, to electric wave of UWB system that is small output