• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.47 no.9
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• pp.617-628
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• 2019

The currently considered pyrotechnic separation nut is separated through the complicated process, because it has many internal moving parts and two variable-volume chambers connected by the vent hole. Therefore, it has many design parameters. Some of these are the contact angles between internal moving parts, the masses of the internal moving parts, the inner diameter of the push rod protrusion, the initial volumes of the chambers, the mass of the explosive charge, and the diameter of the vent hole. To improve the pyrotechnic separation nut, it is necessary to understand how the behavior of the separation nut is changed according to design parameters. In this point of view, parametric studies are carried out using the previously proposed prediction model for pyrotechnic separation nut behaviors. In each case, the parameter of the interest is changed while the others are kept unchanged. From the results, it is investigated how each design parameter influences the separation behavior.

• The korean journal of orthodontics
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• v.53 no.6
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• pp.358-364
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• 2023

Objective: This study aimed to three-dimensionally evaluate the pharyngeal airway space (PAS) of patients with anterior open bite (AOB) by using cone-beam computed tomography (CBCT) and compare the findings with those obtained in individuals with normal occlusion. Methods: The open bite group (OBG, n = 25) consisted of patients with an anterior overbite of -3 mm or less, while the control group (n = 25) consisted of age- and sex-matched individuals with an anterior overbite of 1-3 mm, Angle Class I malocclusion (1° ≤ point A-nasion-point B angle ≤ 4°), and a normodivergent profile (22° ≤ Frankfort mandibular plane angle ≤ 28°). After the CBCT data were reconstructed into a three-dimensional image, the PAS was segmented into four parts, and the volume of each part was measured. Pharyngeal airway length (PAL) and the area and transverse width of the part showing minimal constriction were also measured. Pearson's correlation analysis was used to evaluate the correlation between changes in the PAS and the amount of anterior overbite. Results: The OBG showed a significantly narrower airway space in the nasopharyngeal, hypopharyngeal, and total airway volumes. The OBG also showed a significantly smaller area and transverse width of the part with minimal constriction. The OBG showed a significantly longer PAL, but there was no correlation between the amount of anterior overbite and the changes in PAS. Conclusions: The PAS was associated with AOB. Patients with AOB had a narrower PAS and a smaller part showing minimal constriction.

• IEMEK Journal of Embedded Systems and Applications
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• v.18 no.6
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• pp.267-275
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• 2023

This paper presents the development of specialized software for annotating volume-of-interest on ¹⁸F-FDG PET/CT images with the goal of facilitating the studies and diagnosis of head and neck cancer (HNC). To achieve an efficient annotation process, we employed the SE-Norm-Residual Layer-based U-Net model. This model exhibited outstanding proficiency to segment cancerous regions within ¹⁸F-FDG PET/CT scans of HNC cases. Manual annotation function was also integrated, allowing researchers and clinicians to validate and refine annotations based on dataset characteristics. Workspace has a display with fusion of both PET and CT images, providing enhance user convenience through simultaneous visualization. The performance of deeplearning model was validated using a Hecktor 2021 dataset, and subsequently developed semi-automatic annotation functionalities. We began by performing image preprocessing including resampling, normalization, and co-registration, followed by an evaluation of the deep learning model performance. This model was integrated into the software, serving as an initial automatic segmentation step. Users can manually refine pre-segmented regions to correct false positives and false negatives. Annotation images are subsequently saved along with their corresponding ¹⁸F-FDG PET/CT fusion images, enabling their application across various domains. In this study, we developed a semi-automatic annotation software designed for efficiently generating annotated lesion images, with applications in HNC research and diagnosis. The findings indicated that this software surpasses conventional tools, particularly in the context of HNC-specific annotation with ¹⁸F-FDG PET/CT data. Consequently, developed software offers a robust solution for producing annotated datasets, driving advances in the studies and diagnosis of HNC.

• Journal of Korean Society of Transportation
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• v.29 no.2
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• pp.111-121
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• 2011

This paper discusses a method for optimizing the semi-actuated traffic signal control system by adjusting the initial interval according to the number of vehicles waiting for the green light in the actuated phase. We also present a Left-Turn actuated traffic signal control strategy that examines the vehicular noise in the detection area and determines the phase extension and the gap-out. In order to detect the vehicles in real-time, an image detector's Video Image Tracking technology was adopted. A 'Zone in Zone'method was implemented, and the image detection area is segmented into three zones: 1) Zone1 for verifying a vehicles obligatory presence, 2) Zone2 for counting the standby vehicles, and 3) Zone3 for examining the number of vehicles that have passed. The on-site assessment of the Left Turn Actuated Control is carried out using CORSIM, and the results show that the Control Delay decreased by 23.10%, 15.06%, and 4.34% compared to the delays resulted from pre-timed control, semi-actuated control-1 and semi-actuated control-2 traffic signal control systems respectively. The Queue Time also decreased by 36.24%, 20.10% and the Total Time by 14.36%, 7.02% for the same scenario. Which clearly demonstrates the operational efficiency. A sensitivity analysis reveals that the improvement from the propose traffic control strategy tends to increase as the through traffic volume reaches a saturated condition and the left-turn traffic volume decreases.

• Journal of the Korea Computer Graphics Society
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• v.24 no.4
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• pp.29-38
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• 2018

In this paper, we propose an automatic segmentation method of meniscus in knee MR images by automatic meniscus localization, multi-atlas-based locally-weighted voting, and patch-based edge feature classification. First, after segmenting the bone and knee articular cartilage, the volume of interest of the meniscus is automatically localized. Second, the meniscus is segmented by multi-atlas-based locally-weighted voting taking into account the weights of shape and intensity distribution in the volume of interest of the meniscus. Finally, to remove leakage to the collateral ligaments with similar intensity, meniscus is refined using patch-based edge feature classification considering shape and distance weights. Dice similarity coefficient between proposed method and manual segmentation were 80.13% of medial meniscus and 80.81 % for lateral meniscus, and showed better results of 7.25% for medial meniscus and 1.31% for lateral meniscus compared to the multi-atlas-based locally-weighted voting.

• Investigative Magnetic Resonance Imaging
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• v.9 no.1
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• pp.2-8
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• 2005

Purpose : The purpose of this study was to implement a software to visualize tumor and its surrounding fiber tracts simultaneously using diffusion tensor imaging and examine the feasibility of our software for investigating the influence of tumor on its surrounding fiber connectivity. Material and Methods : MR examination including T1-weigted and diffusion tensor images of a patient with brain tumor was performed on a 3.0 T MRI unit. We used the skull-striped brain and segmented tumor images for volume/surface rendering and anatomical information from contrast-enhanced T1-weighted images. Diffusion tensor images for the white matter fiber-tractography were acquired using a SE-EPI with a diffusion scheme of 25 directions. Fiber-tractography was performed using the streamline and tensorline methods. To correct a spatial mismatch between T1-weighted and diffusion tensor images, they were coregistered using a SPM. Our software was implemented under window-based PC system. Results : We successfully implemented the integrated visualization of the fiber tracts with tube-like surfaces, cortical surface and the tumor with volume/surface renderings in a patient with brain tumor. Conclusion : Our result showed the feasibility of the integrated visualization of brain tumor and its surrounding fiber tracts. In addition, our implementation for integrated visualization can be utilized to navigate the brain for the quantitative analysis of fractional anisotropy to assess changes in the white matter tract integrity of edematic and peri-edematic regions in a number of tumor patients.

• Korean Journal of Veterinary Research
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• v.14 no.1
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• pp.9-16
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• 1974

The literature on the hematology of dairy cattle contains very important information of physiological and clinical field, but a comprehensive survey on the blood picture of Holstein cows has not been made yet in Korea. The object of the present investigation was to make good this deficiency, and to suggest standards for the blood picture of Holstein cows kept under average farming condition in this country. Observations were made on the blood picture of 30 healthy non-pregnant Holstein cows aging from 6 to 10 years. All of them were selected at random from 15 livestock farms of Deajeon area in order to determine the hematological values from January to Feburary, 1974. The ranges and mean values of erythrocyte count, hemoglobin in blood, hematocrit value, mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, and total and differential leukocyte count were determined. The result obtained in this work were summerized as follows: 1. Ranges and mean values(with standard error) of erythrocyte count, hemoglobin in blood and hematocrit values were 4.90~7.82 and $5.83{\pm}0.12{\times}10^6/mm^3$, 7.8~10.3 and $8.7{\pm}0.11g/100ml$, and 26~38 and $30.2{\pm}0.53$ mI/100 ml, respectively. 2. Mean corpuscular hemoglobin, mean corpuscular volume, and mean corpuscular hemoglobin concentration showed ranges and mean values(with standard error) of 13.2~17.4 and $14.8{\pm}0.22$ pg, 46.0~71.8 and $52.3{\pm}0.31{\mu}m^3$, and 21.6~32.7 and $28.6{\pm}0.47$ g/100 ml, respectively. 3. Total leukocyte count showed a range of 6,300~13,600 and a mean value(with standard error) of $10,035{\pm}346/mm^3$. 4. Ranges and mean values(with standard error) of differential leukocyte counts of total neutrophil were 21~40 and $36.4{\pm}0.7%$, 1,638~4,080 and $3,233{\pm}111/mm^3$, of band neutrophil 0~9 and $3.9{\pm}0.5%$, 0~1,028 and $390{\pm}54/mm^3$, of segmented neutrophil 18~35 and $28.4{\pm}0.7%$, 1,386~3,672 and $2,842{\pm}103/mm^3$, of lymphocyte 46~69 and $55.3{\pm}1.1%$, 3,380~8,976 and $5,535{\pm}263/mm^3$, of monocyte 0~4 and $1.7{\pm}0.2%$, 0~324 and $116{\pm}21/mm^3$, of eosinophil 4~15 and $10.8{\pm}0.6%$, 540~1,725 and $1,082{\pm}72/mm^3$. No basophil was observed in this work.

• Korean Journal of Veterinary Research
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• v.30 no.2
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• pp.157-162
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• 1990

The hematologic values were examined from 74 healthy mixed breed dogs in the area of Seoul. The results obtained are summarized as follows; 1. Mean${\pm}$SD values and ranges of red blood cell(RBC) count were $6.16{\pm}0.92{\times}10^6/{\mu}l$ and $4.40{\sim}8.62{\times}10^6/{\mu}l$, of hemoglobin(Hb) content $14.90{\pm}2.42g/100ml$ and 8.7~19.2g/100ml, of packed cell volume(PCV) $45.47{\pm}6.16ml/100ml$ and 30~57ml/100ml, of mean corpuscular volume (MCV) $74.80{\pm}6.83fl$ and 54.08~90.90fl, of mean corpuscular hemoglobin (MCH) $24.41{\pm}3.91pg$ and 14.19~32.97pg, of mean corpuscular hemoglobin concentration (MCHC) $32.07{\pm}3.24g/100ml$ and 22.23~39.76g/100ml, respectively. 2. The RBC count value in the age group of 3~4 years was higher (p<0.05) than the total RBC count value. The Hb content value in the age group of less than 6 months was lower (p<0.01) but in the age group of 1~2 years and the age group of 3~4 years were higher (p<0.05, p<0.01) than the total Hb content value. The PCV value in the age group of less than 6 months was lower (p<0.05) than the total PCV value. The MCHC values in the age group of 1~2 years and the age group of 3~4 years were higher (p<0.01, p<0.05) than the total MCHC value. 3. Mean${\pm}$SD values and ranges of white blood cell (WBC) count were $11.26{\pm}3.05{\times}10^3/{\mu}l$ and $6.30{\sim}18.4{\times}10^3/{\mu}l$, of band neutrophil $2.97{\pm}1.44%$ and 1~10%, of segmented neutrophil $62.81{\pm}4.92%$ and 42~70, of lymphocyte $30.55{\pm}5.69%$ and 17~50%, of monocyte $2.49{\pm}0.84%$ and 1~5%, of eosinophil $1.81{\pm}1.175$ and 1~8%, respectively. 4. The WBC count value in the age group of 7~12 months was lower (p<0.05) but in the age group of 3~4 years was higher (p<0.05) than the total WBC count value. The band neutrophil values in the age group of 1~2 years and the age group of 3~4 years were higher (p<0.05, p<0.01) than the total band neutrophil value.

• (The)Study of the Eastern Classic
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• no.36
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• pp.375-402
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• 2009

In this study, the researcher put together the changing process of Chinese Confucian into Korean Confucian Thought in the dimension of Chiin 'Governing of Others. By analyzing 'Seonghak jibyo' which is reinterpretation of 'Daehak' and also academic enrichment, the researcher investigated the aspects of acceptance of 'Daehak' in Joseon Period. 'Daehak' was the basic textbook for 'Emperorship Learning'(帝王學, 'Jewang Hak') as well as 'Sage Learning'(聖學, 'Seong Hak') over the whole Joseon Period, and it can be understood that 'Seonghak jibyo'- the Essentials of Sagely Learning compiled by Yulgok(栗谷) is the totalization of such learning. Yulgok organized the system of 'Seonghak jibyo' largely in five volumes and placed Samgangnyeong(三綱領, Three Doctrines or Essential Principles) and Paljomok(八條目, Eight Articles) of 'Daehak' in an appropriate manner. Among those, 'Chiin' was discussed intensively in the Volume Three, 'Jeonga'(正家-Family in Correct State) and also the Volume Four, 'Uijeong'(爲政 the king exercises government by means of his virtue). In the volume, 'Jeonga', Yulgok clearly arranged the core virtues for which the family is obliged to put into practice in everyday life having segmented the contents of the doctrine of Jega(齊家-to order family relationships) in 'Daehak', and, in 'Uijeong', Yulgok deepened the contents of 'Chiguk Pyeongcheonha'(治國平天下, ordering the state, bringing peace to the whole world) and presented consciousness on the spirit of contemporary as well as the practice of the state managements in an affirmative manner. These prove the validity of learning steps by presenting the practice guideline to fit the situation while well preserving the basic system of Confucian thought that leads to 'Chiin' (治人-'Governing of Others' or Governance of humankind) based on 'Sugi'(修己, the cultivation of the self). And such viewpoints feature the characteristics of Joseon Confucian Thought which had been through more abundant enrichment process than Chinese Confucian. Therefore, Yulgok's thoughts expounded in The Essentials of Sagely Learning(聖學輯要, 'Seonghak jibyo') can be regarded as criteria to understand humanity and arts cherished by Joseon people, as well as the distinctive features of politics.

• Journal of Radiation Protection and Research
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• v.26 no.2
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• pp.93-99
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• 2001

Voxel head phantom for overcoming the limitation of mathematical phantom in depleting anatomical details was constructed and example dose calculation for BNCT was performed. The repeated structure algorithm of the general purpose Monte Carlo code, MCNP4B was applied for yokel Monte Carlo calculation. Simple binary yokel phantom and combinatorial geometry phantom composed of two materials were constructed for validating the voxel Monte Carlo calculation system. The tomographic images of VHP man provided by NLM(National Library of Medicine) were segmented and indexed to construct yokel head phantom. Comparison of doses for broad parallel gamma and neutron beams in AP and PA directions showed decrease of brain dose due to the attenuation of neutron in eye balls in case of yokel head phantom. The spherical tumor volume with diameter, 5cm was defined in the center of brain for BNCT dose calculation in which accurate 3 dimensional dose calculation is essential. As a result of BNCT dose calculation for downward neutron beam of 10keV and 40keV, the tumor dose is about doubled when boron concentration ratio between the tumor to the normal tissue is $30{\mu}g/g$ to $3{\mu}g/g$. This study established the voxel Monte Carlo calculation system and suggested the feasibility of precise dose calculation in therapeutic radiology.