• Restorative Dentistry and Endodontics
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• v.48 no.2
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• pp.16.1-16.11
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• 2023

Objectives: The aim of this study was to evaluate the influence of peak kilovoltage (kVp) and a metal artifact reduction (MAR) tool on image quality and the diagnosis of vertical root fracture (VRF) in cone-beam computed tomography (CBCT). Materials and Methods: Twenty single-rooted human teeth filled with an intracanal metal post were divided into 2 groups: control (n = 10) and VRF (n = 10). Each tooth was placed into the socket of a dry mandible, and CBCT scans were acquired using a Picasso Trio varying the kVp (70, 80, 90, or 99), and the use of MAR (with or without). The examinations were assessed by 5 examiners for the diagnosis of VRF using a 5-point scale. A subjective evaluation of the expression of artifacts was done by comparing random axial images of the studied protocols. The results of the diagnoses were analyzed using 2-way analysis of variance and the Tukey post hoc test, the subjective evaluations were compared using the Friedman test, and intra-examiner reproducibility was evaluated using the weighted kappa test (α = 5%). Results: The kVp and MAR did not influence the diagnosis of VRF (p > 0.05). According to the subjective classification, the 99 kVp protocol with MAR demonstrated the least expression of artifacts, while the 70 kVp protocol without MAR led to the most artifacts. Conclusions: Protocols with higher kVp combined with MAR improved the image quality of CBCT examinations. However, those factors did not lead to an improvement in the diagnosis of VRF.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.7 no.4
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• pp.355-362
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• 2017

Recently, UAV(Unmanned Aerial Vehicle) have been utilized in various fields, including surveys, mapping, and spatial analysis, depending on the increase in demand for spatial information and UAV is receiving a lot of attention due to rapid data acquisition and economic viability. In this study, the applicability of UAV image images was analyzed for urban disaster prevention. UAV images were acquired for the study area and digital surface model and ortho image were generated through data processing. Also, the process using PPK(Post Processed Kinematic) GNSS method is compared with existing method. Through the research, it was able to effectively deploy urban disaster prevention information about the target area, and displayed the effectiveness of the methods for efficient comparison with existing unmanned aerial photogrammetry. If the PPK technique is applied to thethe disaster prevention field, it is expected that the work flow in the field of rapid data acquisition and disaster prevention data construction can be greatly improved.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.38 no.6
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• pp.573-581
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• 2020

Using CCTV images and weather parameters, a method for estimating PM (Particulate Matter) index was proposed, and an experiment was conducted. For CCTV images, we proposed a method of estimating the PM index by applying a deep learning technique based on a CNN (Convolutional Neural Network) with ROI(Region Of Interest) image including a specific spot and an full area image. In addition, after combining the predicted result values by deep learning with the two weather parameters of humidity and wind speed, a post-processing experiment was also conducted to calculate the modified PM index using the learned regression model. As a result of the experiment, the estimated value of the PM index from the CCTV image was R2(R-Squared) 0.58~0.89, and the result of learning the ROI image and the full area image with the measuring device was the best. The result of post-processing using weather parameters did not always show improvement in accuracy in all cases in the experimental area.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2007.10a
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• pp.109-112
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• 2007

Definition-Enhancement of the digitalized image has been being made researches continuously due to application a camera to a mobile-apparatus and the advent of a digital camera. In particular, the inputted image from a sensor goes through the process of ISP(Image Signal Process) prior to output as a visual image. The high-frequency components are offset by LPF(Low Pass Filter) that eliminates the noise of high spatial-frequency at the moment. In this paper, we propose an algorithm that outputs more vivid image by using adaptive-HPF(High Pass Filter) that has apt coefficients for diverse conditions of an image edge, nevertheless we do not employ any Edge-Detection algorithm to enhance a blurred image.

• Journal of the Korean Home Economics Association
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• v.44 no.9
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• pp.41-50
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• 2006

This study examines the characteristics of the military look in modern fashion. The materials for the study are mainly precedent studies and related literature, although fashion portfolios and magazines, domestic and international, are used for the exploratory study. The results of the study are as follows. First, the military look for women dismantles the sexual symbolism endowed with the clothes by expressing a neutral charm out of dichotomy image between genders. The neutral expression of the military look, different from the military look of the 20th century, provides a chance to feature a new image by pursuing more individual freedom than human itself. Second, the military-look emphasizes feminine sensual charm through exposing, concealing, or decorating with ornaments which are transformed from the elements of the military clothes, This is different from the past military look that expressed masculine rigidity through simplifying the details and emphasizing the male body silhouette. Third, the military look produces a deconstruction image instead of just showing its intrinsic thoughts or symbolic message through combining design elements or symbolic details of the military look with other images, transforming and exaggerating the shapes, or mixing the time point of views reinterpreting the present or the future image.

• Journal of Biomedical Engineering Research
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• v.29 no.6
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• pp.431-435
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• 2008

Quantitative information of a three dimensional(3D) kinematics of joint is very useful in knee joint surgery, understanding how knee kinematics related to joint injury, impairment, surgical treatment, and rehabilitation. In this paper, an automated 2D/3D image matching technique was developed to estimate the 3D in vivo knee kinematics using dual X-ray images. First, a 3D geometric model of the knee was reconstructed from CT scan data. The 3D in vivo position and orientation of femoral and tibial components of the knee joint could be estimated by minimizing the pixel by pixel difference between the projection images from the developed 3D model and the given X-ray images. The accuracy of the developed technique was validated by an experiment with a cubic phantom. The present 2D/3D image matching technique for the estimation of in vivo joint kinematics could be useful for pre-operative planning as well as post-operative evaluation of knee surgery.

• The Research Journal of the Costume Culture
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• v.16 no.1
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• pp.70-87
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• 2008

The purpose of this study is to examine how the entertainment culture has influenced the fashion of the college students since the year 2000, and to analyze the fashion trends of those who enjoy their entertainment culture. The entertainment culture is, therefore, perceived in the most sensitive way by the college students, who belong to the latter period of their adolescence, while influencing them. Especially recently, the entertainment culture of the college students has emerged as a new symbol of the overall fashion. And its effect on the fashion has become conspicuous. The 21st entertainment culture is comprised of "club culture", which is an off-line fad, and "on-line game culture". The result of this study is as follows: Firstly, the formative way that the so-called "club culture" influenced the fashion of the college students shows that their overall fashion trends are characterized by a 'caports image' and a 'childlike-amusing image'. Secondly, the formative fashion style, influenced by the so-called "on-line game culture", presents a 'post- structural image' by using heterogeneous material in order to introduce a new point of view, and by transforming the creation style and design. And it also presents a 'homosexual image' by crossing the attractiveness of both genders. This study is baseds on the documents study.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.658-663
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• 2003

A process of 3-D stereo particle image velocimetry(PIV)was developed for the measurement of an illuminated sliced section field of 3-D complex flows. The present method includes modeling of camera by a calibrator based on the homogeneous coordinate system, transformation of the oblique-angled image to the right-angled image, identification of 2-D velocity vectors by 2-D cross-correlation equation, stereo matching of 2-D velocity vectors of two cameras, accurate calculation of 3-D velocity vectors by homogeneous coordinate system, removal of error vectors by a statistical method followed by a continuity equation criteria, and finally 3-D display as the post processing. An experimental system was also used for the application of the proposed method. Two high speed digital CCD cameras and an Argon-Ion Laser for the illumination were adopted to clarify the time-dependent characteristics of the leading edge extension(LEX) in a highly swept shape applied to a delta wing found in modern air-fighters.

• The Journal of Korean Academy of Prosthodontics
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• v.47 no.1
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• pp.53-60
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• 2009

Statement of problem: At present, as the esthetic demands are on the increase, there are many ongoing studies for tooth-colored post and cores. Most of them are about fiber post and prefabricated zirconia post, but few about one-piece milled zirconia post and core using CAD/CAM (computer-aided design/computer-aided manufacturing) technique. Purpose: The objective of this study was to compare microleakage of endodontically treated teeth restored with three different tooth-colored post and cores. Material and methods: Extracted 27 human maxillary incisors were cut at the cementoenamel junction, and the teeth were endodontically treated. Teeth were divided into 3 groups (n=9); restored with fiber post and resin core, prefabricated zirconia post and heat-pressed ceramic core, and CAD/CAM milled zirconia post and core. After the preparation of post space, each post was cemented with dual-polymerized resin cement (Variolink II). Teeth were thermocycled for 1000 cycles between $5-55^{\circ}C$ and dyed in 2% methylene blue at $37^{\circ}C$ for 24 hours. Teeth were sectioned (bucco-lingual), kept the record of microleakage and then image-analyzed using a microscope and computer program. The data were analyzed by one-way ANOVA and Scheffe's multiple range test (${\alpha}=0.05$). Results: All groups showed microleakage and there were no significant differences among the groups (P>.05). Prefabricated zirconia post and heat-pressed ceramic core showed more leakage in dye penetration at the post-tooth margin, but there was little microleakage at the end of the post. Fiber post and resin core group and CAD/CAM milled zirconia post and core group indicated similar microleakage score in each stage. Conclusion: Prefabricated zirconia post and heat-pressed ceramic core group demonstrated better resistance to leakage, and fiber post and resin core group and CAD/CAM milled zirconia post and core group showed the similar patterns. The ANOVA test didn't indicate significant differences in microleakage among test groups. (P>.05)

• The Journal of Art Theory & Practice
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• no.15
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• pp.51-79
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• 2013

This paper examines the characteristics of post-modern self-portrait photography. Characteristics of postmodernism associated with the "loss of centeredness," such as the death of the author, interdisciplinarity, and intertextuality, brought about a number of changes within the self-portrait. The distinction between post-modern and modern self-portraiture can be characterized by the following qualities: appropriation, the use of photography, and the utilization of the human body as an art. The characteristics of post-modern self-portrait photography can be represented through the works of Cindy Sherman, Orlan, and Morimura Yasumasa. By presenting prototypical women in her works, Cindy Sherman not only represents images of those women, but also exposes her fictitious role in the work. She creates a distance between herself in the works and herself in reality and discloses a paternalistic gaze. Meanwhile, Orlan transforms her face into a distorted image and presents it as an alternative identity that is representative of postmodernism. She corrodes the standard concept of identity through plastic surgery and treats the face not as a place where the identity stays, but as a simple body part or fragment of skin. Orlan's post-human face is malleable according to the artist's desire to raise the issue of what the human face is, and opposes the structure of modernism. Morimura Yasumasa also appropriates images from masterpieces and presents a hybrid identity between Eastern and Western, male and female, original and replica, and subject and object. In order to dissect social prejudice, he puts forth every single structural dichotomy that coexists in his self-portrait and suppresses a strong ego. He also studies the relationship between 'seeing' and being 'seen' by trading the painter's role from that of the subject to that of the object.