• Imaging Science in Dentistry
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• v.47 no.2
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• pp.117-122
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• 2017

Purpose: The aim of this study was to compare the use of 3-dimensional (3D) laser scanning and cone-beam computed tomography (CBCT) as methods of root surface measurement. Materials and Methods: Thirty teeth (15 maxillary first premolars and 15 mandibular first premolars) from 8 patients who required extractions for orthodontic treatment were selected. Before extraction, pre-treatment CBCT images of all the patients were recorded. First, a CBCT image was imported into simulation software (Mimics version 15.01; Materialise, Leuven, Belgium) and the root surface area of each tooth was calculated using 3-Matic (version 7.01, Materialise, Leuven, Belgium). After extraction, all the teeth were scanned and the root surface area of each extracted tooth was calculated. The root surface areas calculated using these 2 measurement methods were analyzed using the paired t-test (P<.05). Correlations between the 2 methods were determined by calculating the Pearson correlation coefficient. The intraclass correlation coefficient(ICC) was used to assess intraobserver reliability. Results: The root surface area measurements ($230.11{\pm}41.97mm^2$) obtained using CBCT were slightly greater than those ($229.31{\pm}42.46mm^2$) obtained using 3D laser scanning, but not significantly (P=.425). A high Pearson correlation coefficient was found between the CBCT and the 3D laser scanner measurements. The intraobserver ICC was 1.000 for 3D laser scanning and 0.990 for CBCT. Conclusion: This study presents a novel CBCT approach for measuring the root surface area; this technique can be used for estimating the root surface area of non-extracted teeth.

• Korean journal of communication and information
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• v.28
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• pp.141-169
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• 2005

This study considered the factor of the adoption of the satellite DMB. This study focus on the TV audience's demographic traits and media usage. The results are follows : 1) the elder-aged group, high-educated group and car driver group have high intention to be subscriber for the satellite DMB service. 2) the white collar group and the middle income group have high intention to be subscriber for the satellite DMB service. 3) the many media use group and the many function use of mobile phone group have high intention to be subscriber for the satellite DMB service. 4) the local TV audience like the entertainment genre in video and audio service and the information genre in data service 5) the local TV audience don't mind of the re-transmission territorial broadcasting by the satellite DMB service.

• The Journal of the Acoustical Society of Korea
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• v.21 no.1
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• pp.82-88
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• 2002

In this paper, we proposed a audio indexing method that is used wavelet transform for audio data retrieval. It is difficult for audio data to make a efficient audio data index because of its own particular properties, such as requirement of large storage, real time to transfer and wide bandwidth. An audio data in del using wavelet transform make it possible to index and retrieval by using the particular wavelet transform properties. Our proposed indexing method doesn't separate data to several blocks. Therefore we use both high-pass and low-pass parts of last level coefficient of wavelet transform. Audio data indexing is made by applying the string matching algorithm to high-pass part and zero-crossing histogram to low-pass part. These are transformed to the continued strings, Through this method, we described a retrieval efficiency. The retrieval method is done by comparing the database index string to the query string and then data of minimum values is chosen to the result. Our simulation decided proper comparative coefficient and made known changing of retrieval efficiency versus audio data length. The results show that the proposed method improves retrieval efficiency compared to conventional method.

• Journal of the Korean Arthroscopy Society
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• v.5 no.1
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• pp.41-44
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• 2001

The muscular button holing of vastus medialis is a very rare case of irreducible knee dislocations, and rapid reduction of this can diminish the complications which delayed reduction accompanies. We diagnosed a patient who appeared posterolateral dislocation of the knee and protrusion of the medial femoral condyle with MRI grossly. That was reduced by open arthrotomy, followed the reconstruction of both cruciate ligaments and repair of medial collateral ligament. Patient didn't show joint instability except minor posterior sagging and had full range of motion postoperatively after 10 months.

• Korean Journal of Psychosomatic Medicine
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• v.9 no.1
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• pp.37-48
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• 2001

Objectives : The purpose of this study was to evaluate the difference of psychometric analysis among patients with Post-traumatic organic mental disorder according to the lesion of MRI finding of traumatic brain injury. Methods : We divided 35 patients into 4 groups according to the lesion of MRI finding of brain injury. We evaluated the difference of the subscales of MMPI and K-WAIS among 4 groups with Post-traumatic organic mental disorder by ANOVA. Results : We found no significant difference of all subscales of MMPI and K -WAIS among 4 groups by ANOVA. Compared Rt hemispheric injury group with Lt hemispheric injury group by independent t-test, the depression scale in MMPI scored significantly higher in Lt hemispheric injury group, and the block design in K-WAIS scored significantly lower in Rt hemispheric injury group. Conclusion : This study suggests that Lt hemispheric injury be significantly related to depression, and Rt hemispheric injury be significantly related to visuospatial ability.

• Journal of Broadcast Engineering
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• v.6 no.1
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• pp.82-97
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• 2001

In this paper, we describe a software implementation of a digital TV stream analyzer that can be used for analyzing and verifying digital TV bitstreams on personal computes. It accepts as input MPEG-2 transport streams (TS's) already stored on hard disks and doesn't require any special hardware. After classifying TS packets into program specific information(PSI) TS section auido, video, program clock reference (PCR) private data and null packets, it displays their contents through a graphic user interface along with the syntax elements of the TS header. Also it displays the decoded I frame nearest in time axis the TS packet currently shown This feature helps pin pointing the specific location of problematic parts in bitstreams. The bitsteam analyzer provides the compliance test of MPEG-2 Systems standard and the data injection functionality with which one can easily insert additional data to existing MPEG-2 bitstreams. Using the resulting system one can produce at low test streams for interactive broadcasting and data broadcasting for laboratory use.

• Journal of Yeungnam Medical Science
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• v.9 no.2
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• pp.269-274
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• 1992

Authers retrospectively analyzed ultrasonographic findings of 12 cases of breast carcinomas which were proven pathologocally at Yeungnam University Hospital from March 1992 to August 1992. Classically, breast carcinomas were described as irregular and lobulated hypoechoic solid masses with inhomogenous internal echoes and frequent attenuation of the sound beam. And other additional ultrasonographic findings were echogenic rim, disruptions of superficial layer, microcalcification, skin thickening and so on. In our studies, not all of these findings of breast carcinomas were found in each case, but most of these findings were noted. However, several studies have demonstrated considerable overlap in the ultrasonographic appearance of benign lesions and carcinoma. Thus, accurate sonographic determination of the type of solid mass is not possible with current ultrasonographic imaging techniques and criteria. For more accurate diganosis of breast lesions, sonographic and other imaging techniqes are interpreted together.

• Journal of Chest Surgery
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• v.29 no.3
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• pp.360-364
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• 1996

Chylothorax is denned by extravasation of the milky fluid to pleural cavity from the thoracic duct or it's main branches due to operative trauma, congenital lesions, diagnostic procedures, tumor, etc. Another rare cause is diffuse pulmonary Iymphangiomatosis which is uncommon and not well charact rized. We experienced a case of the bilateral chylothorax caused by the diffuse pulmonary Iymphangiomatosis. The patient was at years old girl with symptoms of coughing and febrile sensation, and the chest radiographs showed bilateral pleural effusion and interstitial infiltrates. The laboratory data of the pleural effusion was identified as chile. Uncontrollable with closed tube thoracostomy, division of tHe thoracic duct and biopsy were decided. Biopsy showed anastomosing endothelial lined spaces along the pulmonary Iymphatic routes especially in pleural and interlobar septum, and smooth muscle at the proliferative interstitium of the Iymphatic duct was observed. Postoperatively, chylothorax was controlled with several trial of chemical pleurodesis. Af'leer discharge from the hospital, she was well for ten months follow up.

• Journal of Korean Society of Transportation
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• v.29 no.3
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• pp.73-82
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• 2011

Recent advancement in traffic surveillance systems has allowed the researchers to obtain more detailed vehicular movement such as individual vehicle trajectory data. Understanding the characteristics of interactions between leading and following vehicles in the traffic flow stream is a backbone for designing and evaluating more sophisticated traffic and vehicle control strategies. This study proposes a methodology for estimating rear-end crash potential, as a probabilistic measure, in real-time based on the analysis of vehicular movements. The methodology presented in this study consists of three components. The first predicts vehicle position and speed every second using a Kalman filtering technique. The second estimates the probability for the vehicle's trajectory to belong to either 'changing lane' or 'going straight'. A binary logistic regression (BLR) is used to model the lane-changing decision of the subject vehicle. The other component calculates crash probability by employing an exponential decay function that uses time-to-collision (TTC) between the subject vehicle and the front vehicle. The result of this study is expected to be adapted in developing traffic control and information systems, in particular, for crash prevention.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.40 no.4
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• pp.275-285
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• 2003

The now video coding standard H.264 employs variable block size motion compensation, multiple references, and quarter-pel motion vector accuracy. These techniques are key features to accomplish higher coding gain, however, at the same time main factors that increase overall computational complexity. Therefore, in order to apply H.264 to many applications, key techniques are requested to improve their speed. For this reason, we propose a fast motion estimation which is suited for variable block size motion communication. In addition, we propose a fast mode decision method to choose the best mode at early stage. Experimental results show the reduction of the number of SAT SATD calculations by a factor of 4.5 and 2.6 times respectively, when we compare the proposed fast motion estimation and the conventional MVFAS $T^{［8-10］}$. Besides, the number of RDcost computations is reduced by about 45%. Therefore, the proposed methods reduces significantly its computational complexity without noticeable coding loss.