• Convergence Security Journal
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• v.6 no.3
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• pp.117-126
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• 2006

Bayesian inference and model selection method for software reliability growth models are studied. Software reliability growth models are used in testing stages of software development to model the error content and time intervals between software failures. In this paper, could avoid multiple integration using Gibbs sampling, which is a kind of Markov Chain Monte Carlo method to compute the posterior distribution. Bayesian inference for general order statistics models in software reliability with diffuse prior information and model selection method are studied. For model determination and selection, explored goodness of fit (the error sum of squares), trend tests. The methodology developed in this paper is exemplified with a software reliability random data set introduced by of Weibull distribution(shape 2 & scale 5) of Minitab (version 14) statistical package.

• Journal of the Institute of Electronics and Information Engineers
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• v.49 no.12
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• pp.113-123
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• 2012

Recently, various attempts have been made to apply Intelligent Transportation System under various environments and conditions. Consequently, an accurate license plate recognition regardless of vehicle location and viewing angle is required. In this paper, we propose a novel license plate recognition system which exploits a) the format of license plates to remove false candidates of license plates and to extract characters in license plates and b) the characteristics of Hangul for accurate character recognition. In order to eliminate false candidates of license plates, the proposed method first aligns the candidates of license plates horizontally, and compares the position and the shape of objects in each candidate with the prior information of license plates provided by Korean Ministry of Construction & Transportation. The prior information such as aspect ratio, background color, projection image is also used to extract characters in license plates accurately applying an improved local binarization considering luminance variation of license plates. In case of recognizing Hangul in license plates, they are initially grouped according to their shape similarity. Then a super-class method, a hierarchical analysis based on key feature points is applied to recognize Hangul accurately. The proposed method was verified with high recognition rate regardless of background image, which eventually proves that the proposed LPR system has high performance regardless of the vehicle location or viewing angle.

• Journal of Digital Convergence
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• v.14 no.6
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• pp.237-244
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• 2016

The purpose of this study examines the influence of anchoring and adjustment according to regularity of snack's shape. Especially this study choose 'choco chip' as a snack with regularity to compare with 2012's study. The results of this study are as follows. 1) The anchoring and adjustment also appears in 'choco chip' with regularity. But statistical meaning is different from the result of prior study. 2) The difference of anchoring effect reduced according to additional verbal information in 'choco chip' with regularity. but has no statistical meaning of interaction effect. However the causes of two results are different. 3) The interaction effect of cognitive load(without vs. moderate vs. high) is meaningful statistically. difference of anchoring effect reduced according to additional verbal information in 'choco chip' with regularity in 'choco chip' with regularity. This study provides strategic implication that it overcomes the limitation of the prior resuarch and may reinforce the biased judgement by cognitive overload.

• Journal of the Korean Society of Costume
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• v.55 no.4 s.94
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• pp.138-150
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• 2005

Phrygia headgear has an important meaning from the perspectives of costume history and cultural exchanges in ancient times. This study is to investigate the prototype of Phrygia headgear through analysis of its manufacturing methods and styles on the basis of prior studies on ancient sculptures and literatures conducted by European researchers and to examine its history and meanings. In these ways, this study will be helpful in understanding the importance of Phrygia headgear in cultural exchanges between the East and the West. Results of this study can be summarized as follows: Phrygia headgear was orn by eastern tribes, so it was a symbol of those from the east in ancient times. Phrygia headgear is frequently found in Greek artistic works of 5th to 4th century BC that depicted eastern tribes. Also, this headgear can be observed in artistic works for Mithras, Attis, or other gods. Since Phrygia headgear's shape is similar to that of Homer's helm, many researchers believe that it might be originated from Homer's helm. This headgear made of oxen scrotum(stierbeutel) or its surrounding skin has a long end at the top. This long end is round and drooping toward the front side. From such unique shape, we top. This long end is round and drooping toward the front side. From such unique shape, we top. This long end is round and drooping toward the front side. From such unique shape, we can draw a conclusion that Phrygia headgear was made of oxen scrotum and its surrounding skin. Dependingy on drooping patterns, there are various shapes, such as the round, tightly swollen one worn by Mithras, the tongue-shaped one found in Basilika S. Apolinare Nuovo's mosaic depicting three wise men, the balloon-shaped one frequently found in Greek vases depicting Scythian, and the one drooping to the side depicted in Alexandersarkophag. Further, some Phrygia headgear has covers for neck and ears. For example, Phrygia headgear worn by Persian Satrap tribe has such covers attached to the head part. Meanwhile, Phrygia headgear worn by Amazone tribe does not show such separate covers, Rather, one piece of oxen skin was tanned and finished to make such covers. Wearing Phrygia headgear can be interpreted in several ways. Use of animal's skin for wearing things is a unique aspect in ancient societies because they believed that wearing animal skin would give them power of the animal. Further, Phrygia headgear made of oxen scrotum was a symbol of reproductive power to women.

• Journal of dental hygiene science
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• v.11 no.2
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• pp.121-127
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• 2011

This study was conducted to improve patients satisfaction by comparing patients expectation prior to the implant therapy to patient satisfaction after the implant therapy. The data of 158 patients with dental implant in Seoul, Gyeonggi-Do and Cheonan city was obtained. The results are as follows : 1. 40.5% of patients placed one implant and 36.1 % of patients answered that the average cost for each implant is from 1,500,000 to 2,000,000won. 23.4% of them answered they decided to have implant because no tooth preparation is required. 2. Overall, the expectation level for implant therapy in general properties, women showed higher level of expectation than men. Especially, 'Implant has a longer life than other denture' showed significant difference between women(4.29) and men(3.87). Expectation by age, 'Implant has similar color and shape' was found the highest in age 20(4.38). Satisfaction by general properties, 'No tooth preparation required' was found the highest in age 20(4.57) and was statistically significant(p<.002). 3. Comparing patients' expectation prior to implant therapy to satisfaction afterward, 'Implant prevents jawbone resorption and keeps facial appearance' showed 3.7 of expectation but satisfaction was found increased to 3.87(p=.020). No tooth preparation required' was found 3.95 in expectation prior to implant therapy but after therapy it was found 4.23 in satisfaction (p<.001). 4. Overall satisfaction in implant therapy was found 4.25, recommendation to other patients was found 4.18 and repurchase was found 4.17.

• Journal of KIISE:Software and Applications
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• v.36 no.11
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• pp.936-946
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• 2009

A graph cuts method has recently attracted a lot of attentions for image segmentation, as it can globally minimize energy functions composed of data term that reflects how each pixel fits into prior information for each class and smoothness term that penalizes discontinuities between neighboring pixels. In previous approaches to graph cuts-based automatic image segmentation, GMM(Gaussian mixture models) is generally used, and means and covariance matrixes calculated by EM algorithm were used as prior information for each cluster. However, it is practicable only for clusters with a hyper-spherical or hyper-ellipsoidal shape, as the cluster was represented based on the covariance matrix centered on the mean. For arbitrary-shaped clusters, this paper proposes graph cuts-based image segmentation using mean shift analysis. As a prior information to estimate the data term, we use the set of mean trajectories toward each mode from initial means randomly selected in $L^*u^*{\upsilon}^*$ color space. Since the mean shift procedure requires many computational times, we transform features in continuous feature space into 3D discrete grid, and use 3D kernel based on the first moment in the grid, which are needed to move the means to modes. In the experiments, we investigate the problems of mean shift-based and normalized cuts-based image segmentation methods that are recently popular methods, and the proposed method showed better performance than previous two methods and graph cuts-based automatic image segmentation using GMM on Berkeley segmentation dataset.

• Journal of the Korean Society for Heat Treatment
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• v.32 no.5
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• pp.212-223
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• 2019

This study is to investigate the relationship between microstructural factors and tensile properties after aging heat treatment of the 15-5PH stainless steel at the temperature range of $450^{\circ}C$, $500^{\circ}C$ and $550^{\circ}C$ for various time. For the aging time of 2 hours, hardness showed maximum at $450^{\circ}C$ and then decreased with increasing aging temperature. While, hardness decreased gradually during aging $450^{\circ}C$, $500^{\circ}C$ and $550^{\circ}C$ from 1 hour to 5 hours but the hardness nearly unchanged until the 100 hours after 5 hours aging. When aging at $450^{\circ}C$, Cu atoms preferentially aggregated at the prior austenite grain boundaries and martensite lath boundaries, and Cu concentration at those boundaries was nearly unchanged even after aging for 100 hours. Therefore it was suggested that the coherency is still maintained after 100 hours aging at $450^{\circ}C$. Aging at $500^{\circ}C$ and $550^{\circ}C$ results in an increase in the concentration of Ni at the martensite lath boundaries and prior austenite grain boundaries, resulting in the formation of reversed austenite. Especially, when aged at $550^{\circ}C$ for 100 hours, the concentration of Ni remarkably increased at those boundaries, and thus the microstructure of herring bone shape was appeared. Considering the migration of Ni atom to the lath boundaries and prior austenite grain boundaries, Ni atoms contributed greatly to the formation of reversed austenite. On the other hand, it was found that Cu atoms hardly moving to those boundaries may not be contributed to the formation of reversed austenite. When aging at $450^{\circ}C$, the coarsening of the precipitated Cu atoms proceeded very slowly with increasing aging time, therefore the decrease in strengths were small but the reduction area was considerably increased due to the softening of the matrix. At the aging temperature of $500^{\circ}C$ and $550^{\circ}C$, the strengths decreased and the elongation and reduction area increased due to the appearance of the reversed austenite. Especially, the increase of reduction area was remarkable.

• Journal of the Korea institute for structural maintenance and inspection
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• v.17 no.3
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• pp.56-64
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• 2013

The wind resistant capacity of bridges with a span of less than 200m is typically evaluated by Wind Resistant Design Manual for Highway Bridges in Japan. Also, the first vertical frequency plays an important role in the evaluation of their aerodynamic performance. An unexpected vortex-induced vibration of Nielsen arch bridge with span of 183m designed by this manual has been measured by monitoring system during typhoon. The amplitude of vibrations was about 2 times than the allowable vibration displacement. This paper presents the feature of vortex-induced vibration of this Nielsen arch bridge based on measured wind velocity, wind direction, and responses at midspan of main girder. From the result of FFT, the $1^{st}$ mode shape of the bridge is antisymmetric and the $2^{nd}$ is symmetric. Also, the dominant vibration of the bridge is the $2^{nd}$ vertical mode. According to these results, the $2^{nd}$ vertical vibration mode of this Nielsen arch bridge is prior to the first for the estimation of wind resistance capacity.

• Archives of Craniofacial Surgery
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• v.10 no.2
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• pp.71-75
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• 2009

Purpose: Recently, orbital wall fracture is common injuries in the face. Facial CT is essential for the accurate diagnosis and appropriate treatment to reconstruct of the orbital wall. The objective of this study was to report the method for accurate measurement of area and shape of the bony defect in the blow-out fractures using facial CT in prior to surgery. Methods: The authors experienced 46 cases of orbital wall fractures and examined for diplopia, sensory disturbance in the area of distribution of the infraorbital nerve, and enophthalmos in the preoperation and followed 1 months after surgery, from August 2007 to May 2008. Bony defect was predicted by measuring continuous defect size from 3 mm interval facial CT. Copying from the defect model (template), we reconstructed orbital wall with resorbable sheet (Inion $CPS^{(R)}$ Inion Oy, Tampere, Finland). Results: One months after surgery using this method, 26 (100%) of the 26 patients improved in the diplopia and sensory disturbance in the area of distribution of the infraorbital nerve. Also 8 (72.7%) of the 11 patients had enophthalmos took favorable turn. Conclusion: This accurate and time-saving method is practicable for determining the location, shape and size of the bony defect. Using this method, we can reconstruct orbital wall fracture fastly and precisely.

• Journal of KIISE
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• v.42 no.10
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• pp.1222-1230
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• 2015

Segmentation of the anterior cruciate ligament (ACL) in knee MRI remains a challenging task due to its inhomogeneous signal intensity and low contrast with surrounding soft tissues. In this paper, we propose a multi-atlas-based segmentation of the ACL in knee MRI with locally-aligned probabilistic atlas (PA) in an iterative graph cuts framework. First, a novel PA generation method is proposed with global and local multi-atlas alignment by means of rigid registration. Second, with the generated PA, segmentation of the ACL is performed by maximum-aposteriori (MAP) estimation and then by graph cuts. Third, refinement of ACL segmentation is performed by improving shape prior through mask-based PA generation and iterative graph cuts. Experiments were performed with a Dice similarity coefficients of 75.0%, an average surface distance of 1.7 pixels, and a root mean squared distance of 2.7 pixels, which increased accuracy by 12.8%, 22.7%, and 22.9%, respectively, from the graph cuts with patient-specific shape constraints.