• Ocean and Polar Research
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• v.25 no.spc3
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• pp.353-360
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• 2003

Estimation of undrained shear strength $(S_u)$ of clayey soils from piezocone penetration test (CPTu), which has widely been known as one of very promising in situ test methods, requires piezocone factors. Empirical correlations are generally utilized to derive piezocone factors, but previous studies on the empirical piezocone factors are site-specific and in some cases need engineering characteristics, which should be obtained from additional laboratory tests. In this study, empirical cone factors were evaluated by comparing 6 CPTu results at Shihwa region in Korea with reference $S_u$ values obtained from field vane test (FVT). From previous CPTu results of other regions in Korea as well as the results herein, the correlations between piezocone factor, $N_{kT}$ and CPTu results were investigated and three simplified evaluation methods of $S_u$ using only CPTu results were presented. The $S_u$ values estimated by $(q_T-{\sigma}_v)/{\sigma}'_v$ method shows better matches with those obtained from laboratory tests for marine clays at Shihwa region.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2009.01a
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• pp.425-428
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• 2009

We have researched and developed the caricature generation system PICASSO. PICASSO outputs the deformed facial caricature by comparing input face with prepared mean face. We specialized it as PICASSO-2 for exhibiting a robot at Aichi EXPO2005. This robot enforced by PICASSO-2 drew a facial caricature on the shrimp rice cracker with the laser pen. We have been recently exhibiting another revised robot characterized by a brush drawing. This system takes a couple of facial images with CCD camera, extracts the facial features from the images, and generates the facial caricature in real time. We experimentally evaluated the performance of the caricatures using a lot of data taken in Aichi EXPO2005. As a result it was obvious that this system were not sufficient in accuracy of eyebrow region extraction and mouth detection. In this paper, we propose the improved methods for eyebrow region extraction and mouth detection.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.78.1-78.1
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• 2011

We report on a photometric study of star clusters in the circumnuclear star-forming region of nearby barred spiral galaxy NGC 1672. We use FUV to NIR imaging data (FUV, U, B, V, R, $H{\alpha}$, I, and H) in the Hubble Space Telescope (HST) archive. We have selected 89 star clusters with V<21.8 (MV<-9) mag in the central 600 pc region, and have derived their age & mass by comparing their colors with theoretical population synthesis models. Most of the star clusters are mildly reddened (E(B-V)~0.2 on average), but some star clusters suffer from severe reddening (E(B-V)>0.6). The mass of the star clusters are in the range from $10^4\;M_{\odot}$ to $10^7\;M_{\odot}$. About half of them are more massive than $10^5\;M_{\odot}$. Their ages range from 1 Myr to several 100 Myr, and concentrate at ~6 Myr and ~40 Myr. It indicates that the episodic starburst in the circumnuclear star-forming region lasted at least several 100 Myr. We find no obvious azimuthal age gradient, but we find a radial age gradient in some regions. We discuss these properties with theoretical expectations.

• Journal of Institute of Control, Robotics and Systems
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• v.16 no.1
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• pp.69-76
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• 2010

The segmentation of moving object in video sequence is a core technique of intelligent image processing system such as video surveillance, traffic monitoring and human tracking. A typical method to segment a moving region from the background is the background subtraction. The steps of background subtraction involve calculating a reference image, subtracting new frame from reference image and then thresholding the subtracted result. One of famous background modeling is Gaussian mixture model (GMM). Even though the method is known efficient and exact, GMM suffers from a problem that includes false pixels in ROI (region of interest), specifically shadow pixels. These false pixels cause fail of the post-processing tasks such as tracking and object recognition. This paper presents a method for removing false pixels included in ROT. First, we subdivide a ROI by using shape characteristics of detected objects. Then, a method is proposed to classify pixels from using histogram characteristic and comparing difference of energy that converts the color value of pixel into grayscale value, in order to estimate whether the pixels belong to moving object area or shadow area. The method is applied to real video sequence and the performance is verified.

• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.3166-3168
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• 2000

This paper proposed variable threshold dual rate ADPCM coding method which is modified from the standard ADPCM of ITU G.726 for speech quality improvement. The speech quality of variable threshold dual rate ADPCM is better than single rate ADPCM at noisy environment without increasing the complexity by using ZCR(Zero Crossing Rate). In this case, ZCR is used to divide input signal samples into two categories(noisy & speech). The samples with higher ZCR is categorized as the noisy region and the samples with lower ZCR is categorized as the speech region. Noisy region uses higher threshold value to be compressed by 16Kbps for reduced bit rates and the speech region uses lower threshold value to be compressed by 40Kbps for improved speech quality. Comparing with the conventional ADPCM, which adapts the fixed coding rate. the proposed variable threshold dual rate ADPCM coding method improves noise character without increasing the bit rate. For real time applications, ZCR calculation was considered as a simple method to obtain the background noise information for preprocess of speech analysis such as FFT and the experiment showed that the simple calculation of ZCR can be used without complexity increase. Dual rate ADPCM can decrease the amount of transferred data efficiently without increasing complexity nor reducing speech quality. Therefore result of this paper can be applied for real-time speech application such as the internet phone or VoIP.

• Bulletin of the Korean Space Science Society
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• 2010.04a
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• pp.32.5-32.5
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• 2010

We present the FUV continuum map of The Taurus-Auriga-Perseus complex, which is one of the largest local association of dark clouds. The map is well consistent with the dust extinction and the CO emission map of the T-P-A region. The region is divided into 3 sub-regions by diffuse FUV intensities and the spectra of each region imply that the radiation field due to the Per OB2-association can be a main source of the H2 fluorescent emission of the nearby cloud region. We used the PDR H2 model, named CLOUD, developed by van Dishoeck &Black for the sake of comparing our results to the H2 model.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.43 no.5 s.311
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• pp.30-36
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• 2006

In this paper, a new type of written image segmentation based on relative comparison of region areas is proposed. The original image is composed of two distinctive regions; information and background. Compared with this binary original image, the observed one is the gray scale which is represented with complex regions with speckles and noise due to degradation or contamination. For applying threshold or statistical approach, there occurs the region-deformation problem in the process of binarization. At first step, the efficient iterated conditional mode (ICM) which takes the lozenge type block is used for regions formation into the binary image. Secondly the information region is estimated through selecting action and restored its primary state. Not only decision of the attachment to a region but also the calculation of the magnitude of its area are carried on at each current pixel iteratively. All region areas are sorted into a set and selected through the decision parameter which is obtained statistically. Our experiments show that these approaches are effective on ink-rubbed copy image (拓本 'Takbon') and efficient at shape restoration. Experiments on gray scale image show promising shape extraction results, comparing with the threshold-segmentation and conventional ICM method.

• Wind and Structures
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• v.22 no.2
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• pp.211-234
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• 2016

Super long-span bridges provide people with great convenience, but they also bring traffic safety problems caused by strong wind owing to their high decks. In this paper, the large eddy simulation together with dynamic mesh technology in computational fluid dynamics (CFD) is used to explore the mechanism of a moving vehicle's transient aerodynamic force in crosswind, the regularity and mechanism of the vehicle's aerodynamic forces when it passes through a bridge tower's wake zone in crosswind. By comparing the calculated results and those from wind tunnel tests, the reliability of the methods used in the paper is verified on a moving vehicle's aerodynamic forces in a bridge tower's wake region. A vehicle's aerodynamic force coefficient decreases sharply when it enters into the wake region, and reaches its minimum on the leeward of the bridge tower where exists a backflow region. When a vehicle moves on the outermost lane on the windward direction and just passes through the backflow region, it will suffer from negative lateral aerodynamic force and yaw moment in the bridge tower's wake zone. And the vehicle's passing ruins the original vortex structure there, resulting in that the lateral wind on the right side of the bridge tower does not change its direction but directly impact on the vehicle's windward. So when the vehicle leaves from the backflow region, it will suffer stronger aerodynamic than that borne by the vehicle when it just enters into the region. Other cases of vehicle moving on different lane and different directions were also discussed thoroughly. The results show that the vehicle's pneumatic safety performance is evidently better than that of a vehicle on the outermost lane on the windward.

• KIEAE Journal
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• v.15 no.2
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• pp.103-107
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• 2015

Purpose: Since September 1st, 2013, subjects of the evaluation have been expanded, and the evaluation standard has been detailed to enable Building energy rating system for all buildings. Accordingly, the new evaluation program (ECO2) has been developed, and therefore, apartment applied after September 1st, 2013 were evaluated with the new evaluation program. Therefore, this research suggests the improvement plan to figure out reasons for the evaluation result calculation and to calculate the evaluation results close to the actual energy usage by analyzing and comparing primary energy consumption as a result of the new evaluation program (ECO2) and actual heating energy usage on the same building. Method: When comparing evaluation results of the new evaluation program (ECO2) and actual heating energy usage, the tendency was similar but different. Also when comparing seasonally, the tendency was similar, but the different between actual heating energy usage and primary energy consumption during winter is greater than during spring or fall, and when comparing seasonal electric usage, heating alternatives were used through increased electrical usage during winter compared to during spring or fall. Result: Therefore, when evaluating apartment with the new program (ECO2) in the future, evaluation items relevant to the use of heating alternatives should be added, and the modification factor should be added according to the region. Based on the evaluation results of the research and actual energy usage, the Modification factors of the central part and the southern part were calculated respectively as 0.5 and 0.8.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.3 no.1
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• pp.19-28
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• 1973

The author has studied maxillo-facial anatomical landmarks using Status X with two methods. The one has performed by application of contrast media on the human dry skull, the other has performed on living human skull as control group. Comparing the panagraphs taken by two methods, the author has drawn following results: 1. The panagraphs revealed the undistorted, highly sharp panoramic shadows of each jaw on a film. 2. Diminishing the inserted anode tube overlapping-free representation of the anterior teeth was taken. 3. Alternating the head position of the objects, direction of anode tube and film placing, the shadows of temporo-mandibular joint and zygomatic arch were taken without overlapping the other bone tissues. 4. In the panagraphs applied various shaped contrast media to each anatomical landmark, a radio-anatomical atlas which is necessary to interpret various bone tissues was taken. 5. In order to interpret panagraphic shadows easily, the author has tried this study by comparing the films of the living human skull with the films of the human dry skull applied contrast media.