• Nuclear Engineering and Technology
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• v.48 no.3
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• pp.785-794
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• 2016

The Argonne National Laboratory of the United States and the Kharkov Institute of Physics and Technology of the Ukraine have been collaborating on the design, development and construction of a neutron source facility at Kharkov Institute of Physics and Technology utilizing an electron-accelerator-driven subcritical assembly. The electron beam power is 100 kW using 100-MeV electrons. The facility was designed to perform basic and applied nuclear research, produce medical isotopes, and train nuclear specialists. The biological shield of the accelerator building was designed to reduce the biological dose to less than 5.0e-03 mSv/h during operation. The main source of the biological dose for the accelerator building is the photons and neutrons generated from different interactions of leaked electrons from the electron gun and the accelerator sections with the surrounding components and materials. The Monte Carlo N-particle extended code (MCNPX) was used for the shielding calculations because of its capability to perform electron-, photon-, and neutron-coupled transport simulations. The photon dose was tallied using the MCNPX calculation, starting with the leaked electrons. However, it is difficult to accurately tally the neutron dose directly from the leaked electrons. The neutron yield per electron from the interactions with the surrounding components is very small, ~0.01 neutron for 100-MeV electron and even smaller for lower-energy electrons. This causes difficulties for the Monte Carlo analyses and consumes tremendous computation resources for tallying the neutron dose outside the shield boundary with an acceptable accuracy. To avoid these difficulties, the SOURCE and TALLYX user subroutines of MCNPX were utilized for this study. The generated neutrons were banked, together with all related parameters, for a subsequent MCNPX calculation to obtain the neutron dose. The weight windows variance reduction technique was also utilized for both neutron and photon dose calculations. Two shielding materials, heavy concrete and ordinary concrete, were considered for the shield design. The main goal is to maintain the total dose outside the shield boundary less than 5.0e-03 mSv/h during operation. The shield configuration and parameters of the accelerator building were determined and are presented in this paper.

• Journal of Korean society of Dental Hygiene
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• v.9 no.4
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• pp.874-884
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• 2009

Objectives : This study was to investigate the level of oral health concern and the purchase behavior of environmental friendly agricultural products and to determine the relationship between oral health concern and the purchase behavior of environmental friendly agricultural products. Methods : The subjects were 99 male(29.7%) and 234 female(70.3%), who were over 20 years with mean age of 39.6 years. The data was collected using personal interviews and a self administrated questionnaire from August 1 to September 30, 2008. Oral health concern was measured using the 7-items, and the purchase behavior of environmental friendly agricultural products was measured using the 7-items. The data were analysed with t-test, one-way ANOVA and multiple logistic regression using the SPSS 15.0 windows. Results : Regarding oral health concern, the subjects was a mean of 2.86 out of a maximum 5 points. There were differences in the level of oral health concern according to the purchase behavior of environmental friendly agricultural products(experience, period, frequency, price, weight). Conclusions : These results suggest that the strategies of habitual use environmental friendly agricultural products to put in practice oral health promoting behavior is needed to improve quality of life in people.

• Korean Journal of Community Nutrition
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• v.6 no.5
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• pp.819-829
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• 2001

The purpose of this study was to investigate the difference of general characteristics, menopause status, dietary patterns and nutrient intakes between women aged from 30 to 65 years old with a hypercholesterolemia group and normocholesterolemia group. The subjects were classified as belonging to the hypercholesterolemia group or normocholesterolemia group barred on The Guidelines for Korean Hyperlipidemia. Dietary intakes of fatty acids were measured by means of a 24-hr recall method with food models and measuring tools. We analyzed both data sets together using analysis of variance chi-square test and student's t-test(SPSS for WINDOWS, version 7.5). Significance was defied as a p value < 0.05. The results obtained are summarized as follows. Mean age and BMI of the hypercholesteroemia group were significantly higher than those of the normocholesterolemia group. Intakes of cereal, vegetables, mushrooms and sea food in the normocholesterolemia group were significantly higher than those in the hypercholesterolemia group. Most of the nutrient intakes were not significantly different between the normocholesterolemia group and the hypercholesterolemia group. However, vitamin E intake of the normocholesterolemia group was significantly higher than that of the hypercholesterolemia group. There was a significant negative correlation between vitamin E intake and serum TC(r = -.363, p < 0.001) and LDL-C(r = -.359, p < 0.001). In addition, Serum TG had significantly correlation with carbohydrate(r = 0.137, p < 0.001) and vitamin E intake(r = -0.134, p < 0.001). Therefore, women who suffered from hypercholesterolemia were recommended to control body weight, and to consume foods containing high vitamin E and foods containing high dietary fiber such as vegetables, mushrooms, and sea food.

• The Journal of Advanced Prosthodontics
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• v.5 no.2
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• pp.110-117
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• 2013

PURPOSE. Polymethyl methacrylate (PMMA) is the most commonly used denture base material despite typically low in strength. The purpose of this study was to improve the physical properties of the PMMA based denture base resins (QC-20, Dentsply Ltd., Addlestone, UK; Stellon, AD International Ltd, Dentsply, Switzerland; Acron MC; GC Lab Technologies Inc., Alsip, Japan) by copolymerization mechanism. MATERIALS AND METHODS. Control group specimens were prepared according to the manufacturer recommendations. In the copolymer groups; resins were prepared with 5%, 10%, 15% and 20% acrylamide (AAm) (Merck, Hohenbrunn, Germany) content according to the moleculer weight ratio, respectively. Chemical structure was characterized by a Bruker Vertex-70 Fourier transform infrared spectroscopy (FTIR) (Bruker Optics Inc., Ettlingen, Germany). Hardness was determined using an universal hardness tester (Struers Duramin, Struers A/S, Ballerup, Denmark) equipped with a Vickers diamond penetrator. The glass transition temperature ($T_g$) of control and copolymers were evaluated by Perkin Elmer Diamond DSC (Perkin Elmer, Massachusetts,USA). Statistical analyses were carried out using the statistical package SPSS for Windows, version 15.0 (SPSS, Chicago, IL, USA). The results were tested regarding the normality of distribution with the Shapiro Wilk test. Data were analyzed using ANOVA with post-hoc Tukey test (P<.01). RESULTS. The copolymer synthesis was confirmed by FTIR spectroscopy. Glass transition temperature of the copolymer groups were higher than the control groups of the resins. The 10%, 15% and 20% copolymer groups of Stellon presented significantly higher than the control group in terms of hardness. 15% and 20% copolymer groups of Acron MC showed significantly higher hardness values when compared to the control group of the resin. Acrylamide addition did not affect the hardness of the QC-20 resin significantly. CONCLUSION. Within the limitation of this study, it can be concluded that copolymerization of PMMA with AAm increased the hardness value and glass transition temperature of PMMA denture base resins.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.8
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• pp.344-349
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• 2017

Wall-climbing robots have been developed for various purposes, such as cleaning skyscraper windows, maintaining large structures, and welding vessels. Conventional wall-climbing robots use movement systems based on wheels or legs. However, wheeled robots suffer from slipping effects, while legged systems require many actuators and control systems for the complex linkage structure, which also increases the weight of the robot. To overcome these disadvantages, we propose a new wall-climbing robot that walks based on gorilla locomotion. The proposed robot consists of a DC drive motor, a vacuum pump for adsorption, and a micro controller for controlling the system. The performance of the robot was experimentally verified on vertical and horizontal flat surfaces. The robot could be used for various functions in industrial sites or disaster areas.

• The Journal of Korean Obstetrics and Gynecology
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• v.25 no.2
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• pp.174-184
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• 2012

Objectives: The purpose of this study was to observe the early postpartum low back pain and pelvic girdle pain in the Korean medical hospital for 2-weeks. Methods: Fifty-one postpartum women who admitted for postpartum care in Korean hospital from December 3rd, 2011 to January 31st, 2012 had written out pain measurement questionnaires(SF-MPQ, VAS, ODI) three times for 2-weeks. SPSS 18.0 for Windows was used to analyse the data and the independent samples t-test, paired T-test were used to verify the results. Results: 1. Evaluation of low back pain within the first week after birth was as follows: SF-MPQ sensory area was $5.06{\pm}4.41$ points; SF-MPQ emotional areas was $0.86{\pm}1.34$ points; VAS mean was $3.79{\pm}2.02$ points; and ODI mean was $10.27{\pm}6.69$. 2. Early postpartum low back pain and pelvic girdle pain were significantly decreased in SF-MPQ, VAS, and ODI after 2-weeks(p < 0.01). 3. Age, birth type, parity, weight, and BMI increased during pregnancy does not affect the postpartum low back pain and pelvic girdle pain. Conclusions: The top 10% of postpartum low back pain scale was 10.8 points or more in the sensory area of SF-MPQ, and 3 points or more in the affective area of SF-MPQ. In the case of VAS, it was more than 7 points, and ODI was more than 21.8 points. Postpartum back pain with oriental medical treatment was significantly improved.

• Nuclear Engineering and Technology
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• v.50 no.6
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• pp.989-995
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• 2018

Argonne National Laboratory of the United States and Kharkov Institute of Physics and Technology (KIPT) of Ukraine have cooperated on the development, design, and construction of a neutron source facility. The facility was constructed at Kharkov, Ukraine, and its commissioning process is underway. The facility will be used for researches, producing medical isotopes, and training young nuclear specialists. The neutron source facility is designed with a provision to include a cryogenically cooled moderator system-a cold neutron source (CNS). This CNS provides low-energy neutrons, which will be used in the scattering experiment and material structures analysis. Cold neutron guides, coated with reflective material for the low-energy neutrons, will be used to transport the cold neutrons to the experimental site. The cold neutron guides would keep the cold neutrons within certain energy and angular space concentrated inside, while most of the gamma rays and high-energy neutrons are not affected by the cold neutron guides. For the KIPT design, the cold neutron guides need to extend several meters outside the main shield of the facility, and curved guides will also be used to remove the gamma and high-energy neutron. The neutron guides should be installed inside a shield structure to ensure an acceptable biological dose in the facility hall. Heavy concrete is the selected shielding material because of its acceptable performance and cost. Shield design analysis was carried out for the CNS guide hall. MCNPX was used as the major computation tool for the design analysis, with neutron and gamma dose calculated separately. Weight windows variance reduction technique was also used in the shield design. The goal of the shield design is to keep the total radiation dose below the $5.0{\mu}Sv/hr$ guideline outside the shield boundary. After a series of iterative MCNPX calculations, the shield configuration and parameters of CNS guide hall were determined and presented in this article.

• Korean Journal of Applied Biomechanics
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• v.28 no.4
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• pp.227-236
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• 2018

Objective: The purpose of this study was to investigate the effects of a 12-week combined exercise program on gait parameters in elderly women with osteoarthritis. Method: The subjects of this study were 11 elderly women (age: $67.09{\pm}2.47$, height: $157.35{\pm}4.30cm$, weight: $62.49{\pm}6.36kg$) with knee osteoarthritis. The combined exercise program of this study was divided into aerobic exercise and lower extremity strengthening exercises. The exercises were performed for 60 minutes per session, three times a week, for a total of 12 weeks. The maximum joint moments of the hip, knee, and ankle joints with walking were obtained with 8-3D cameras (MX-T20, Vicon, USA) and 2-force plate (AMTI OR6-7-400, AMTI, USA). SPSS Windows version 23.0 was used for statistical analysis. A paired t-test was used for pre-post comparison. An alpha level of .05 was utilized in all tests. Results: The maximum extension moment was significantly higher in the hip joint after P1 on the X axis. The maximum joint moment of P3 in extension was statistically significantly lower after intervention. On the Z axis, the maximum joint moment was significantly lower after the exercise intervention at P3. There was a statistically significant increase in the extension moment of the left and right knee joints in the X axis after exercise intervention. In the right ankle joint, P1 (plantar flexion moment) showed a statistically significant high moment after exercise intervention. Conclusion: These results suggest that combined exercise, including lower limb and aerobic exercise, may have a positive effect on mobility and walking moments in patients with osteoarthritis of the knee.

• Journal of Broadcast Engineering
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• v.27 no.4
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• pp.538-547
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• 2022

Recently introduced image classification methods using Transformers show remarkable performance improvements over conventional neural network-based methods. In order to effectively consider regional features, research has been actively conducted on how to apply transformers by dividing image areas into multiple window areas, but learning of inter-window relationships is still insufficient. In this paper, to overcome this problem, we propose a transformer structure that can reflect the relationship between windows in learning. The proposed method computes the importance of each window region through compression and a fully connected layer based on self-attention operations for each window region. The calculated importance is scaled to each window area as a learned weight of the relationship between the window areas to re-calibrate the feature value. Experimental results show that the proposed method can effectively improve the performance of existing transformer-based methods.

• Journal of radiological science and technology
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• v.38 no.3
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• pp.267-276
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• 2015

The gallbladder(GB) polyps have malignant potential and nowadays are increasing due to the extended use of ultrasonography. Even though there are various reports on the risk of GB polyps, there is few study on the relationship between the presence of metabolic syndrome including serum biochemistry, lifestyle and the development of gallbladder polyps in korean population. The aim of this study is to establish a relationship between the presence of metabolic syndrome including serum biochemistry and the development of gallbladder polyps in korean population. This study conducted on 151 men and 167 women who visited a musculoskeletal hospital in Gyeonggido to have an ultrasound scan of the abdomen from November 2, 2012 to January 31, 2014. They are randomly selected to evaluate the prevalence risk factors were analyzed by comparing various variables between the GB polyp positive and negative. The collected data were analyzed using the personal computer program SPSS version 20.0 for windows. The mean size of the GB polyps was 3.92mm in diameter. Size of GB polyps were less than 10mm in diameter. As to frequency in the people with the GB polyps, the number of patients with the GB polyps was 184(57.9%): the number of metabolic syndrome of them was 114(26.4%); these results showed that risk of the GB polyps got higher at patients with metabolic syndrome. As to the risk of the GB polyps, people with the GB polyps had significantly higher risk than those without the GB polyps, as follows: The risk was significantly 1.061 times higher by weight; 1.186 by BMI; 1.060 by systolic blood pressure; 1.030 by diastolic blood pressure; 1,009 by Total cholesterol; 2.736 by metabolic syndrome; 1.011 by blood sugar on an empty stomach; 1.064 by ESR. The risk factors of GB polyps were found to be weight, BMI, total cholesterol, Triglycerol, Glucose, systolic blood pressure, diastolic blood pressure, ESR and metabolic syndrome. This study has a possibility to be used an indicator to identify the GB polyps, and in the future larger-scale study will have to be conducted to objectify it.