• Imaging Science in Dentistry
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• v.46 no.1
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• pp.33-38
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• 2016

Purpose: Facial asymmetry has been measured by the severity of deviation of the menton (Me) on posteroanterior (PA) cephalograms and three-dimensional (3D) computed tomography (CT). This study aimed to compare PA cephalograms and 3D CT regarding the severity of Me deviation and the direction of the Me. Materials and Methods: PA cephalograms and 3D CT images of 35 patients who underwent orthognathic surgery (19 males and 16 females, with an average age of $22.1{\pm}3.3years$) were retrospectively reviewed in this study. By measuring the distance and direction of the Me from the midfacial reference line and the midsagittal plane in the cephalograms and 3D CT, respectively, the x-coordinates ($x_1$ and $x_2$) of the Me were obtained in each image. The difference between the x-coordinates was calculated and statistical analysis was performed to compare the severity of Me deviation and the direction of the Me in the two imaging modalities. Results: A statistically significant difference in the severity of Me deviation was found between the two imaging modalities (${\Delta}x=2.45{\pm}2.03mm$, p<0.05) using the one-sample t-test. Statistically significant agreement was observed in the presence of deviation (k=0.64, p<0.05) and in the severity of Me deviation (k=0.27, p<0.05). A difference in the direction of the Me was detected in three patients (8.6%). The severity of the Me deviation was found to vary according to the imaging modality in 16 patients (45.7%). Conclusion: The measurement of Me deviation may be different between PA cephalograms and 3D CT in some patients.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.17 no.1
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• pp.1-11
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• 2017

Recently that require digital signatures handwritten for personal use customer information and agree to the Terms of Service agreement or a general sign up. Signature system including an existing handwritten signature are a problem, which may be a platform-dependent, as well as the environment in which to perform the signature vary according to device Status of presence because it is being utilized is implemented on the service platform itself within each company. In this paper, we designed and implemented an integrated system handwritten signature as possible using a cross-browser way to store the handwritten two-dimensional coordinates based on the jQuery it is interspecific directly integrated browser environment. iOS, Android, was tested in an integrated web browser in heterogeneous environments, including PC, it was confirmed that all handwritten signature function is working properly.

• The Journal of the Acoustical Society of Korea
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• v.10 no.2
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• pp.52-60
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• 1991

Sound propagation in a sloping sea bed ocean environment demonstrates ray curvature in a direction parallel to the shoreline. The theoretical analysis of this shows that an ensonified region and a shadow region are formed, and their spatial extents depend on the spatial coordinates of source and receiver, a sloping angle and sourece frequency. The purpose of this experimental study using a sloping sea bed model is to check the theoretical prediction as a part of an ongoing investigation in the ocean environment. The sloping sea bed model used in this experiment had an ideal pressure-release boundaries and a sloping angle of $220.5{\circ}$ A single frequency signal and an impulsive signal were used as omnidirectional point sources. The spatial acoustic field characteristics in the across slope direction were measured using the former and the frequency dependent field characteristics in a specific point were obtained using the latter. It has been found that the analysis for the spatial extent of shadow zone and the frequency dependent field characteristics in the across slope direction, has a good agreement with the theoretical solution.

• Bulletin of the Korean Space Science Society
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• 2011.04a
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• pp.19.2-19.2
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• 2011

In 1861 Nam Byeong-Gil published a book called as "Seonggyeong" which contains a star catalogue (NBGC) with the positions, magnitudes, and star maps for 1449 stars. The NBGC lists only the traditional Chinese stars selected from "the sequel to the Qing Dynasty Star Catalogue and Star Map." To identify each star from the NBGC with modern counterpart, we correct the positions of the Hipparcos stars brighter than 6.5 mag for proper motion, then precess the coordinates to the epoch of the NBGC. For each star in the NBGC, we find the nearest counterpart in the Hipparcos Catalogue (HC). If a much brighter star is at a slightly larger angular distance, we select that star as the secure counterpart. As a result, 95.5% of the stars in the NBGC were identified. We find a very good overall agreement of our results with a previous analysis by Ahn et al. (1996, Journal of the Korean History of Science Society, vol. I). For securely identified stars, we analyse its accuracy on the basis of comparison with data from the HC. The correlation of the errors between right ascensions and declinations is significantly deviated from spherical distribution. The magnitudes recorded in the NBGC correlate well with modern values. The accuracy of position decreases slowly with magnitude. Right ascensions and declinations have error distributions with ${\sigma}$ = 2.0' for the former while the latter with ${\sigma}$ = 1.6', but with much more errors >5' than expected for a Gaussian distribution.

• Smart Structures and Systems
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• v.24 no.6
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• pp.769-781
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• 2019

Dynamic displacement response of civil structures is an important index for in-construction and in-service structural condition assessment. However, accurately measuring the displacement of large-scale civil structures such as high-rise buildings still remains as a challenging task. In order to cope with this problem, a vision-based system with the use of industrial digital camera and image processing has been developed for long-distance, remote, and real-time monitoring of dynamic displacement of supertall structures. Instead of acquiring image signals, the proposed system traces only the coordinates of the target points, therefore enabling real-time monitoring and display of displacement responses in a relatively high sampling rate. This study addresses the in-situ experimental verification of the developed vision-based system on the Canton Tower of 600 m high. To facilitate the verification, a GPS system is used to calibrate/verify the structural displacement responses measured by the vision-based system. Meanwhile, an accelerometer deployed in the vicinity of the target point also provides frequency-domain information for comparison. Special attention has been given on understanding the influence of the surrounding light on the monitoring results. For this purpose, the experimental tests are conducted in daytime and nighttime through placing the vision-based system outside the tower (in a brilliant environment) and inside the tower (in a dark environment), respectively. The results indicate that the displacement response time histories monitored by the vision-based system not only match well with those acquired by the GPS receiver, but also have higher fidelity and are less noise-corrupted. In addition, the low-order modal frequencies of the building identified with use of the data obtained from the vision-based system are all in good agreement with those obtained from the accelerometer, the GPS receiver and an elaborate finite element model. Especially, the vision-based system placed at the bottom of the enclosed elevator shaft offers better monitoring data compared with the system placed outside the tower. Based on a wavelet filtering technique, the displacement response time histories obtained by the vision-based system are easily decomposed into two parts: a quasi-static ingredient primarily resulting from temperature variation and a dynamic component mainly caused by fluctuating wind load.

• Journal of radiological science and technology
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• v.36 no.2
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• pp.123-129
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• 2013

This study investigated the rate of setup variance by the rotating unbalance of gantry in image-guided radiation therapy. The equipments used linear accelerator(Elekta Synergy TM, UK) and a three-dimensional volume imaging mode(3D Volume View) in cone beam computed tomography(CBCT) system. 2D images obtained by rotating $360^{\circ}$and $180^{\circ}$ were reconstructed to 3D image. Catpan503 phantom and homogeneous phantom were used to measure the setup errors. Ball-bearing phantom was used to check the rotation axis of the CBCT. The volume image from CBCT using Catphan503 phantom and homogeneous phantom were analyzed and compared to images from conventional CT in the six dimensional view(X, Y, Z, Roll, Pitch, and Yaw). The variance ratio of setup error were difference in X 0.6 mm, Y 0.5 mm Z 0.5 mm when the gantry rotated $360^{\circ}$ in orthogonal coordinate. whereas rotated $180^{\circ}$, the error measured 0.9 mm, 0.2 mm, 0.3 mm in X, Y, Z respectively. In the rotating coordinates, the more increased the rotating unbalance, the more raised average ratio of setup errors. The resolution of CBCT images showed 2 level of difference in the table recommended. CBCT had a good agreement compared to each recommended values which is the mechanical safety, geometry accuracy and image quality. The rotating unbalance of gentry vary hardly in orthogonal coordinate. However, in rotating coordinate of gantry exceeded the ${\pm}1^{\circ}$ of recommended value. Therefore, when we do sophisticated radiation therapy six dimensional correction is needed.