• Journal of radiological science and technology
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• v.44 no.3
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• pp.189-194
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• 2021

This study was conducted to reduce the exposure dose to the breast and adjacent organs as the number of Mammography increased. Therefore, it has been designed a shield in lead, bismuth + tungsten, and bismuth that does not require to be equipped by the patient, in which each type of shield was compared and analyzed of radiation exposure dose to breast, thyroid, and eye. Using a mammography machine, optically stimulated luminescent dosimeter(OSLD) was inserted to bilateral breast, thyroid, and eye of a dosimetry phantom to measure dose radiated onto the phantom. Shielding device was made in different thickness of 2mm, 3mm, and 5mm and dose evaluation was performed by measuring the dose while using lead, bismuth, and bismuth + tungsten prosthesis. When each shields combined with shielding device, were compared of dose, all showed similar does reduction in the dose to breast, thyroid, and eye in both cranialcaudal and mediolateraloblique view. Based on the current study, bismuth and bismuth + tungsten can replace conventional lead shield and it is anticipated to safely and conveniently reduce radiation exposure to breast, thyroid, and eye with the shield that does not require to be equipped.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.47 no.4
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• pp.269-278
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• 2021

Objectives: The purpose of this animal research was to compare bone regeneration in augmented rabbit maxillary sinuses treated with demineralized particulate human-tooth graft and anorganic bovine bone by immunohistochemical analysis. Materials and Methods: Piezoelectric bilateral sinus augmentation was performed in eight adult rabbits. In the control group, anorganic bovine was grafted in the maxillary sinus following elevation of the sinus membrane. In the experimental group, demineralized human particulate tooth bone was grafted in the sinus. Bone regeneration in augmented sinuses was evaluated by immunohistochemical analysis using various markers of osteoprogenitor cells. Results: The number of bromodeoxyuridine-labeled cells was significantly higher in the experimental group than in the control group at eight weeks. The immunoreactivity of proliferating-cell nuclear antigen was increased slightly in the experimental group relative to the control group at eight weeks. Other bone markers were expressed equally in the two groups. Conclusion: In the rabbit maxillary sinus, higher osteoinduction was correlated with demineralized human particulate tooth bone grafting than with anorganic bovine grafting.

• International Journal of Computer Science & Network Security
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• v.22 no.8
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• pp.242-248
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• 2022

The article presents the analysis of modern methods of automatic comparison of original and unoriginal text to detect textual plagiarism. The study covers two types of plagiarism - literal, when plagiarists directly make exact copying of the text without changing anything, and intelligent, using more sophisticated techniques, which are harder to detect due to the text manipulation, like words and signs replacement. Standard techniques related to extrinsic detection are string-based, vector space and semantic-based. The first, most common and most successful target models for detecting literal plagiarism - N-gram and Vector Space are analyzed, and their advantages and disadvantages are evaluated. The most effective target models that allow detecting intelligent plagiarism, particularly identifying paraphrases by measuring the semantic similarity of short components of the text, are investigated. Models using neural network architecture and based on natural language sentence matching approaches such as Densely Interactive Inference Network (DIIN), Bilateral Multi-Perspective Matching (BiMPM) and Bidirectional Encoder Representations from Transformers (BERT) and its family of models are considered. The progress in improving plagiarism detection systems, techniques and related models is summarized. Relevant and urgent problems that remain unresolved in detecting intelligent plagiarism - effective recognition of unoriginal ideas and qualitatively paraphrased text - are outlined.

• Tuberculosis and Respiratory Diseases
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• v.84 no.3
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• pp.209-216
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• 2021

Background: Endobronchial lung cancer (EBLC) and bronchial anthracofibrosis (BAF) share similar symptoms and radiological findings. The aim of this study was to describe clinical and radiological differences between BAF and EBLC, both of which were confirmed by bronchoscopy. Methods: This was a retrospective study of patients with BAF or EBLC from 2008 to 2014. Data were derived from a bronchoscopy registry made since January 1, 2008. Clinical and radiological characteristics of both diseases were analyzed. Results: Among 3,214 patients who underwent bronchoscopy, 167 and 117 patients were enrolled in BAF and EBLC groups, respectively. BAF occurred more predominantly in older non-smoking female patients with a higher chance of tuberculosis (38.3%) than EBLC (6.0%). Cough, sputum, and dyspnea were common symptoms reported for both groups. Bronchoscopic findings revealed that BAF lesions were more common in multiple lobar bronchi (85.0%) or bilateral bronchi (73.7%). Radiologic findings revealed that bronchial stenosis was the most commonly found lesion in both groups (49.1% and 78.6%, respectively). Rates of peribronchial calcification and bronchial wall thickening were higher in the BAF group. The number of patients with lymph node calcification was also higher in the BAF group. Conclusion: Results of this study demonstrated characteristics of clinical and radiologic findings of BAF and EBLC. Increasing the awareness of both diseases may help clinicians differentiate these two diseases from each other, thus avoiding unnecessary invasive diagnostic procedures.

• Childhood Kidney Diseases
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• v.1 no.1
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• pp.24-30
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• 1997

Purpose: To evaluate the diagnositc value of the absolute and relative renal uptake rates on $^{99m}Tc-DMSA$ renal scan of children with febrile UTI. Method: The absolute and relative renal uptake rates of $^{99m}Tc-DMSA$ were checked in 68 children with febrile urinary tract infection (35 with unilateral focal defect; 13 with bilateral focal defect; and 20 with diffuse bilateral defect) and 49 children with afebrile UTI and normal $^{99m}Tc-DMSA$ renal scan as control. Results: The renal absolute uptake rate in the control group were $21.8{\pm}3.9%(right),\;22.2{\pm}3.9%(left),\;and\;44.2{\pm}7.8%(total)$. The absolute uptake rate gradually increased until the age 12 months and then was stationary. In febrile UTI with unilateral focal defect on the $^{99m}Tc-DMSA$ renal scan, both relative and absolute uptake rates were similarly diagnostic ($41.2{\pm}9.7%,\;16.5{\pm}5.4%$ vs $50.0{\pm}2.6%,\;22.0{\pm}3.9%$, p<0.01). In acute pyelonephritis with bilateral focal defect on the $^{99m}Tc-DMSA$ renal scan, the absolute uptake rate was significantly more diagnostic than the relative uptake rate[$17.3{\pm}5.3%$ (right), $17.4{\pm}5.3%\;(left),\;vs\;21.8{\pm}3.9%,\;(right)\;22.2{\pm}3.9%$, (left)% p<0.01]. In febrile UTI with bilateral diffuse defects on the $^{99m}Tc-DMSA$ renal scan, the absolute uptake rate was significantly diagnostic than the relative uptake rate [$18.1{\pm}3.9%\;(right),\;18.4{\pm}3.8%\;(left),\;vs\;21.8{\pm}3.9%,\;(right)\;22.2{\pm}3.9%$(left), p<0.01]. Conclusion: In the $^{99m}Tc-DMSA$ renal scan, the absolute uptake rate was more useful than the relative uptake rate to evaluate bilateral acute pyelonephritis.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.35 no.4
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• pp.211-220
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• 2013

Purpose: The purpose of this study was to compare the changes in the pharyngeal airway space, tongue and hyoid bone positions according to the orthognathic surgical methods of mandibular prognathism. Methods: The subjects included 30 patients (16 males, 14 females) with the skeletal class III malocclusion. Group 1 (10 patients) underwent bilateral sagittal split ramus osteotomy (BSSRO) only; group 2 (10 patients) underwent BSSRO with genioplasty; and group 3 (10 patients) underwent BSSRO, Le Fort I osteotomy. We measured the lines between the selected upper air way, hyoid bone and tongue landmarks on the lateral cephalometric x-ray films of skeletal class III. The measurements were made preoperation, within 1 week after the operation, 3~6 months after the operation and 1 year after the operation. We compared and analyzed the measurements with matched paired t-test and independent samples t-test. Results: There were no postoperative changes in the nasopharyngeal airway space in group 3. The measurements of group 3 also increased during the follow-up period as compared to the preoperative measurements. In group 1, 2 and 3, the immediate postoperative oropharyngeal and hypopharyngeal airway spaces were decreased. In the following period, the hypopharyngeal airway space returned to the preoperative positions, but the oropharyngeal airway space was not significantly changed. The upper and lower tongue was posteriorly repositioned immediately after the surgery. During the follow-up period, the lower tongue position returned to the preoperative position, and the upper tongue position was not significantly changed. Immediately after the surgery, the B point was moved to the posterior position, and a slight anterior advancement was found in the follow-up period. Conclusion: Patients who received the mandibular setback surgery showed a decrease in the posterior airway space, and those who underwent maxillary advancement showed a significant increase of the nasopharyngeal airway space, which remained stable during the evaluation period. The change of the airway space, position of the hyoid bone and tongue did not differ according to the presence or absence of genioplasty.

• Journal of Trauma and Injury
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• v.26 no.3
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• pp.170-174
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• 2013

Purpose: A flail chest is one of most challenging problems for trauma surgeons. It is usually accompanied by significant underlying pulmonary parenchymal injuries and mayled to a life-threatening thoracic injury. In this study, we evaluated the treatment result for a flail chest to determine the effect of trauma localization on morbidity and mortality. Methods: Between 2004 and 2011, 46 patients(29 males/17 females) were treated for a flail chest. The patients were divided into two group based on the location of the trauma in the chest wall; Group I contained patients with an anterior flail chest due to a bilateral costochondral separation (n=27) and Group II contained patients with a single-side posterolateral flail chest due to a segmental rib fracture (n=19). The location of the trauma in the chest wall, other injuries, mechanical ventilation support, prognosis and ISS (injury severity score) were retrospectively examined in the two groups. Results: Mechanical ventilation support was given in 38 patients(82.6%), and 7 of these 38 patients required a subsequent tracheostomy. The mean ISS for all 46 patients was $19.08{\pm}10.57$. Between the two groups, there was a significant difference in mean ventilator time (p<0.048), but no significant difference in either trauma-related morbidity (p=0.369) or mortality (p=0.189). Conclusion: An anterior flail chest frequently affects the two underlying lung parenchyma and can cause a bilateral lung contusion, a hemopneumothorax and lung hemorrhage. Thus, it needs longer ventilator care than a lateral flail chest does and is more frequently associated with pulmonary complications with poor outcome than a lateral flail chest is. In a severe trauma patient with a flail chest, especially an anterior flail chest, we must pay more attention to the pulmonary care strategy and the bronchial toilet.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.34 no.2
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• pp.100-105
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• 2012

Purpose: In general, the surgical treatment for mandibular retrognathism is represented by two methods, distraction osteogenesis (DO) and mandibular osteotomy surgery. The DO is mostly preferred when the degree of advancement of mandible is large. However, the postoperative stability of mandibular advancement using DO have not been actively investigated. Therefore, in the present study we have compared the postoperative stability between DO and bilateral sagittal split ramus osteotomy (BSSRO) in mandibular retrognathism. Methods: Seven patients who had been treated by DO and thirteen patients with BSSRO were included in this study. Serial lateral cephalograms were analyzed by manual tracing and the amount of the mandibular elongation was measured. To evaluate the postoperative stability, positional changes of the condylar position and B point were analyzed. Results: Mean amount of mandibular advancement was $6.51{\pm}3.57mm$ for BSSRO group and $12.43{\pm}4.35mm$ for DO group, respectively. There was no significant difference in age between the two groups (P>0.05). Mean follow up periods were 10.77 months for BSSRO group and 11.28 months for DO group, respectively. After mandibular advancement, mean positional changes in the condyle were $0.56{\pm}1.43mm$ horizontally and $0.72{\pm}1.61mm$ vertically for BSSRO group and $0.53{\pm}1.56mm$ horizontally and $0.56{\pm}1.75mm$ vertically for DO group, respectively. Mean change of distance from B point to Y-axis was $-1.76{\pm}0.83mm$ for BSSRO group and $-2.14{\pm}1.82mm$ for DO group, respectively. According to the condylar position and B point, there were no significant differences in postoperative stability between the two groups (P>0.05). Conclusion: There was no significant difference in postoperative stability between DO and BSSRO group according to condylar position and B point. Based on the results of the present study, it is hypothesized that DO would be a good treatment choice for severe mandibular retrognathism because DO could achieve more mandibular advancement and concurrent soft tissue elongation.

• Journal of Broadcast Engineering
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• v.26 no.3
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• pp.283-295
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• 2021

This paper proposes a method for generating dense depth map using information of color images and depth map generated based on lidar based on self-organizing map. The proposed depth map upsampling method consists of an initial depth prediction step for an area that has not been acquired from LiDAR and an initial depth filtering step. In the initial depth prediction step, stereo matching is performed on two color images to predict an initial depth value. In the depth map filtering step, in order to reduce the error of the predicted initial depth value, a self-organizing map technique is performed on the predicted depth pixel by using the measured depth pixel around the predicted depth pixel. In the process of self-organization map, a weight is determined according to a difference between a distance between a predicted depth pixel and an measured depth pixel and a color value corresponding to each pixel. In this paper, we compared the proposed method with the bilateral filter and k-nearest neighbor widely used as a depth map upsampling method for performance comparison. Compared to the bilateral filter and the k-nearest neighbor, the proposed method reduced by about 6.4% and 8.6% in terms of MAE, and about 10.8% and 14.3% in terms of RMSE.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.49 no.3
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• pp.125-134
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• 2023

Objectives: The aim of the study was to quantify and compare craniofacial asymmetry in subjects with and without symptoms of temporomandibular joint disorders (TMDs). Materials and Methods: A total of 126 adult subjects were categorized into two groups (63 with a TMDs and 63 without a TMDs), based on detection of symptoms using the Temporomandibular Joint Disorder-Diagnostic Index (TMD-DI) questionnaire. Posteroanterior cephalograms of each subject were traced manually and 17 linear and angular measurements were analyzed. Craniofacial asymmetry was quantified by calculating the asymmetry index (AI) of bilateral parameters for both groups. Results: Intra- and intergroup comparisons were analyzed using independent t-test and Mann-Whitney U test, respectively, with a P<0.05 considered statistically significant. An AI for each linear and angular bilateral parameter was calculated; higher asymmetry was found in TMD-positive patients compared with TMD-negative patients. An intergroup comparison of AIs found highly significant differences for the parameters of antegonial notch to horizontal plane distance, jugular point to horizontal plane distance, antegonial notch to menton distance, antegonial notch to vertical plane distance, condylion to vertical plane distance, and angle formed by vertical plane, O point and antegonial notch. Significant deviation of the menton distance from the facial midline was also evident. Conclusion: Greater facial asymmetry was seen in the TMD-positive group compared with the TMD-negative group. The mandibular region was characterized by asymmetries of greater magnitude compared with the maxilla. Patients with facial asymmetry often require management of temporomandibular joint (TMJ) pathology to achieve a stable, functional, and esthetic result. Ignoring the TMJ during treatment or failing to provide proper management of the TMJ and performing only orthognathic surgery may result in worsening of TMJ-associated symptoms (jaw dysfunction and pain) and re-occurrence of asymmetry and malocclusion. Assessments of facial asymmetry should take into account TMJ disorders to improve diagnostic accuracy and treatment outcomes.