• Radiation Oncology Journal
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• v.20 no.2
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• pp.172-178
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• 2002

Purpose : X-ray film over responds to low-energy photons in relative photon beam dosimetry because its sensor is based on silver bromide crystals, which are high-Z molecules. This over-response becomes a significant problem in clinical photon beam dosimetry particularly in regions outside the penumbra. In intensity modulated radiation therapy (IMRT), the radiation field is characterized by multiple small fields and their outside-penumbra regions. Therefore, in order to use film dosimetry for IMRT, the nature the source of the over-response in its radiation field need to be known. This study is aimed to verify and possibly improve film dosimetry for IMRT. Materials and Method : Modulated beams were constructed by a combination of five or seven different static radiation fields using 6 MeV X-rays. In order to verify film dosimetry, we used X-ray film and an ion chamber were used to measure the dose profiles at various depths in a phantom. In addition, in order to reduce the over-response, 0.01 inch thick lead filters were placed on both sides of the film. Results : The measured dose profiles showed a film over-response at the outside-penumbra and low dose regions. The error increased with depths and approached 15% at a maximum for the field size of $15{\times}15cm^2$ at 10 cm depth. The use of filters reduced the error to 3%, but caused an under-response of the dose in a perpendicular set-up. Conclusion : This study demonstrated that film dosimetry for IMRT involves sources of error due to its over-response to low-energy Photons. The use of filers can enhance the accuracy in film dosimetry for IMRT. In this regard, the use of optimal filter conditions is recommended.

• Journal of the Korean Orthopaedic Association
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• v.56 no.1
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• pp.68-75
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• 2021

Purpose: The purpose of this study was to analyze the motion of the shoulder joint dynamically through a depth sensor-based motion analysis system for the normal group and patients group with shoulder disease and to report the results along with a review of the relevant literature. Materials and Methods: Seventy subjects participated in the study and were categorized as follows: 30 subjects in the normal group and 40 subjects in the group of patients with shoulder disease. The patients with shoulder disease were subdivided into the following four disease groups: adhesive capsulitis, impingement syndrome, rotator cuff tear, and cuff tear arthropathy. Repeating abduction and adduction three times, the angle over time was measured using a depth sensor-based motion analysis system. The maximum abduction angle (θ_max), the maximum abduction angular velocity (ω_max), the maximum adduction angular velocity (ω_min), and the abduction/adduction time ratio (t_abd/t_add) were calculated. The above parameters in the 30 subjects in the normal group and 40 subjects in the patients group were compared. In addition, the 30 subjects in the normal group and each subgroup (10 patients each) according to the four disease groups, giving a total of five groups, were compared. Results: Compared to the normal group, the maximum abduction angle (θ_max), the maximum abduction angular velocity (ω_max), and the maximum adduction angular velocity (ω_min) were lower, and abduction/adduction time ratio (t_abd/t_add) was higher in the patients with shoulder disease. A comparison of the subdivided disease groups revealed a lower maximum abduction angle (θ_max) and the maximum abduction angular velocity (ω_max) in the adhesive capsulitis and cuff tear arthropathy groups than the normal group. In addition, the abduction/adduction time ratio (t_abd/t_add) was higher in the adhesive capsulitis group, rotator cuff tear group, and cuff tear arthropathy group than in the normal group. Conclusion: Through an evaluation of the shoulder joint using the depth sensor-based motion analysis system, it was possible to measure the range of motion, and the dynamic motion parameter, such as angular velocity. These results show that accurate evaluations of the function of the shoulder joint and an in-depth understanding of shoulder diseases are possible.

• The Journal of Korean Society for Radiation Therapy
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• v.28 no.2
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• pp.87-99
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• 2016

Purpose : This study will evaluate the clinical utility by applying clinical schematic that uses monoenergy or dual energy as according to the location of tumors to the stereotactic radiotherapy to compare the change in actual dose given to the real tumor and the dose that locates adjacent to the tumor. Materials and Methods : CT images from a total of 10 patients were obtained and the clinical planning were planned based on the volumetric modulated arc therapy on monoenergy and dual energy. To analyze the change factor in the tumor, Comformity Index(CI) and Homogeneity Index(HI) and maximum dose quantity were each calculated and comparing the dose distribution on normal tissues, $V_{10}$ and $V_5$, first ~ fourth ribs closest to the tumor ($1^{st}{\sim}4^{th}$ Rib), Spinal Cord, Esophagus and Trachea were selected. Also, in order to confirm the accuracy on which the planned dose distribution is really measured, the 2-dimensional ion chamber array was used to measure the dose distribution. Results : As of the tumor factor, CI and HI showed a number close to 1 when the two energies were used. As of the maximum dose, the front chest wall showed 2% and the dorsal tumor showed equivalent value. As of normal tissue, the front chest wall tumors were reduced by 4%, 5% when both energies were used in the adjacent rib and as of trachea, reduced by 11%, 17%. As of the dose in the lung, as of $V_{10}$, it reduced by 1.5%, $V_5$ by 1%. As of the rear chest wall, when both energies were used, the ribs adjacent to the tumors showed 6%, 1%, 4%, 12% reduction, and in the lung dose distribution, $V_{10}$ reduced by 3%, and $V_5$ reduced by 3.1%. The dose measurement in all energies were in accordance to the results of Gamma Index 3mm/3%. Conclusion : It is considered that rather than using monoenergy, utilizing double energy in the clinical setting can be more effectively applied to the superficial tumors.

• Journal of Oral Medicine and Pain
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• v.35 no.2
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• pp.135-147
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• 2010

In this study, the objective masticatory efficiency of two groups of temporomandibular disorder patients, pain and sound groups, was compared with that in a normal group using the MAI (mixing ability Index). The subjective chewing ability was evaluated using questionnaires, such as the Food Intake Ability Index (FIA) and Visual Analogue Scale (VAS). The Oral Health Impact Profile (OHIP)-49K of the patients was also examined to measure the oral health-related quality of life. The results were as follows: 1. The MAI, FIA and VAS in the pain group were significantly lower than in the normal and sound groups. This shows that the chewing efficiency of the pain group was lower than the normal and sound groups (P<0.05). However, there was no significant difference between the sound and normal groups. 2. The OHIP-49K for the oral health-related quality of life showed a significant increase in both the pain and sound groups compared with normal group. This means that the oral health-related quality of life was lower in both the pain and sound groups. 3. There was a correlation between the MAI, FIA and VAS (P<0.01) in all subjects (71 persons). The OHIP-49K was associated with the FIA and VAS. 4. There was a correlation between the FIA and VAS (P<0.05) in the sound group but no correlation in the other groups. 5. There was a correlation between the FIA and VAS in all groups. 6. The VAS was increased significantly in the pain group according to the level of pain reduction after treatment (P<0.05). However, there was no significant increase in the MAI, even though there was an improvement in masticatory efficiency. In addition, there was no difference in the FIA and OHIP-49K according to the level of pain reduction after treatment. In this study, it is believed that pain is a main factor decreasing the masticatory efficiency in patients with temporomandibular disorders. Moreover, TMJ sounds decrease the quality of life but do not decrease the masticatory efficiency. Therefore, it is important to control the pain in order to improve the masticatory efficiency in temporomandibular disorder patients. Moreover, managing both pain and sound can improve the quality of life.

• Radiation Oncology Journal
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• v.26 no.4
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• pp.263-270
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• 2008

Purpose: This study aimed to quantitatively measure the movement of tumors in real-time and evaluate the treatment accuracy, during the treatment of a liver tumor patient, who underwent radiosurgery with a Synchrony Respiratory motion tracking system of a robot CyberKnife. Materials and Methods: The study subjects included 24 liver tumor patients who underwent CyberKnife treatment, which included 64 times of treatment with the Synchrony Respiratory motion tracking system ($Synchrony^{TM}$). The treatment involved inserting 4 to 6 acupuncture needles into the vicinity of the liver tumor in all the patients using ultrasonography as a guide. A treatment plan was set up using the CT images for treatment planning uses. The position of the acupuncture needle was identified for every treatment time by Digitally Reconstructed Radiography (DRR) prepared at the time of treatment planning and X-ray images photographed in real-time. Subsequent results were stored through a Motion Tracking System (MTS) using the Mtsmain.log treatment file. In this way, movement of the tumor was measured. Besides, the accuracy of radiosurgery using CyberKnife was evaluated by the correlation errors between the real-time positions of the acupuncture needles and the predicted coordinates. Results: The maximum and the average translational movement of the liver tumor were measured 23.5 mm and $13.9{\pm}5.5\;mm$, respectively from the superior to the inferior direction, 3.9 mm and $1.9{\pm}0.9mm$, respectively from left to right, and 8.3 mm and $4.9{\pm}1.9\;mm$, respectively from the anterior to the posterior direction. The maximum and the average rotational movement of the liver tumor were measured to be $3.3^{\circ}$ and $2.6{\pm}1.3^{\circ}$, respectively for X (Left-Right) axis rotation, $4.8^{\circ}$ and $2.3{\pm}1.0^{\circ}$, respectively for Y (Crania-Caudal) axis rotation, $3.9^{\circ}$ and $2.8{\pm}1.1^{\circ}$, respectively for Z (Anterior-Posterior) axis rotation. In addition, the average correlation error, which represents the treatment's accuracy was $1.1{\pm}0.7\;mm$. Conclusion: In this study real-time movement of a liver tumor during the radiosurgery could be verified quantitatively and the accuracy of the radiosurgery with the Synchrony Respiratory motion tracking system of robot could be evaluated. On this basis, the decision of treatment volume in radiosurgery or conventional radiotherapy and useful information on the movement of liver tumor are supposed to be provided.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.13 no.2
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• pp.177-192
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• 2018

The mission of the university is to grow young people who will be responsible for the next generation nation to mature society. In particular, the role of universities in the 4th Industrial Revolution era is to foster creative talents. Therefore, innovative changes are required for existing infusion education and employment-oriented college education contents and teaching methodology. In the high youth unemployment rate, entrepreneurship education is spreading to universities to innovate existing organizations and create new jobs. Until now, however, the effects of university entrepreneurship education have been studied mainly in the field of start-up. Therefore, it is very difficult to study various effects on entrepreneurship education. In this study, empirical analysis of the effect of entrepreneurship training on career preparation behaviors of university students who are about to enter the society is verified. The sample of this study was surveyed from August, 2016, and the questionnaire was applied to 393 university students who selected 5 universities and entrepreneurship education. As a result of the analysis, the ability of communicative communication and creative problem solving cultivated through entrepreneurship education had a positive effect on entrepreneurship and self - efficacy, Entrepreneurship and self - efficacy had a positive (+) positive effect on career preparation behavior. However, cooperative communication ability, creative problem solving ability, and effective work behavior ability by entrepreneurship education were not directly related to career preparation behavior. On the other hand, in verifying the mediating effect of entrepreneurship and self - efficacy, it proved that mediating role of positive communication between collaborative communication ability, creative problem solving ability and career preparation behavior. The implications of this study are as follows This study examines the effects of university entrepreneurship education on career preparedness behaviors.In other words, the university proved the direct effect and the mediating effect that affects positively (+) effect on career preparation behaviors by encouraging entrepreneurship and self - efficacy, rather than quantitative extension based on competency. Also, the implication of the parameters (entrepreneurship, self - efficacy) as a key variable for the effect and performance of career preparation behavior was derived.It also suggests that it is necessary to improve the creativity ability of entrepreneurship education so that it can have a direct and meaningful influence on career preparation behavior. First of all, it is urgent to develop a qualitative evaluation index for entrepreneurship education in order to measure these effects. Therefore, further study is required to verify the various implications for future entrepreneurship education, as well as the implications that entrepreneurship education is indispensable for the preparation of university students' careers.

• Progress in Medical Physics
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• v.19 no.4
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• pp.269-275
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• 2008

Although MR imaging is generally applicable to depict knee joint deterioration it, is sometimes occurred to mis-read and mis-diagnose the common knee joint diseases. In this study, we employed magnetization transfer ratio (MTR) method to improve the diagnosis of the various knee joint diseases. Spin-echo (SE) T2-weighted images (TR/TE 3,400-3,500/90-100 ms) were obtained in seven cases of knee joint deterioration, FSE T2-weighted images (TR/TE 4,500-5,000/100-108 ms) were obtained in seven cases of knee joint deterioration, gradient-echo (GRE) T2-weighted images (TR/TE 9/4.56/$50^{\circ}$ flip angle, NEX 1) were obtained in 3 cases of knee joint deterioration, In six cases of knee joint deterioration, fat suppression was performed using a T2-weighted short T1/tau inverse recovery (STIR) sequence (TR/TE =2,894-3,215 ms/70 ms, NEX 3, ETL 9). Calculation of MTR for individual pixels was performed on registration of unsaturated and saturated images. After processing to make MTR images, the images were displayed in gray color. For improving diagnosis, three-dimensional isotropic volume images, the MR tristimulus color mapping and the MTR map was employed. MTR images showed diagnostic images quality to assess the patients' pathologies. The intensity difference between MTR images and conventional MRI was seen on the color bar. The profile graph on MTR imaging effect showed a quantitative measure of the relative decrease in signal intensity due to the MT pulse. To diagnose the pathologies of the knee joint, the profile graph data was shown on the image as a small cross. The present study indicated that MTR images in the knee joint were feasible. Investigation of physical change on MTR imaging enables to provide us more insight in the physical and technical basis of MTR imaging. MTR images could be useful for rapid assessment of diseases that we examine unambiguous contrast in MT images of knee disorder patients.

• Journal of Preventive Medicine and Public Health
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• v.20 no.2 s.22
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• pp.312-321
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• 1987

To investigate the maternal and child factors associated with early detection of cerebral palsy, 74 mothers of cerebral palsy children who were born since January 1, 1980 and being treated at Taegu Rehabilitation Center for the Handicapped, Rehabilitiation Center of Taegu University, St. Paul Children's House and Pusan Welfare Association of Cerebral Palsy Children were interviewed from February to April 1987. There is no association between age of child when parents noticed the child's abnormality and educational level of father but it tend to be detected earlier when education level of mother is college or above compared with high school or under. There is a trend of earlier detection of child's abnormality although statistically not significant in case father is professional or managerial worker, monthly income of father is over \610,000, child is first-born, age of the parents is 34 years or under, child is a boy, and child has periodic well-baby check-up. The child's abnormality is detected earlier when mothers had 7 prenatal visits or more compared with those who had 6 visits or less (p<0.05). Parents noticed the child's abnormality first in 85.1% of the cases whereas doctors detected it first in 2.7% and this percentage was not different whether the child had periodic well-baby check-up or not. The first physician's diagnosis of the children was cerebral palsy in 36.5% and the rest was normal, need for observation, uncertain, etc. Parents took the child to doctor for diagnosis 2-3 months after they noticed the child's abnormality and after the child was diagnosed as cerebral palsy parents either took no therapeutic measure or brought the child to physiotherapy or acupuncture or gave herb medicine before they started specific rehabilitative therapy. For early detection of the cerebral palsy children, teaching of evaluation method for child development should be reinforced both in medical school and clinical training course and should train the specialist for diagnosis and treatment of crippling conditions. Also, public education is needed for the importance of early detection of crippling conditions and currently available methods for diagnosis and treatment.

• The Journal of Korean Academy of Prosthodontics
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• v.48 no.2
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• pp.135-142
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• 2010

Purpose: This study was aimed to compare the margin and internal fitness of single anterior all-ceramic crown zirconia core made by three deferent CAD/CAM systems. Material and methods: Five single zirconia cores were manufactured by three deferent CAD/CAM systems($Cerasys^{(R)}$system, KaVo $Everest^{(R)}$system, $LAVA^{TM}$system). The manufactured zirconia cores were duplicated through the use of replica technique, and a replicated sample was sectioned in the center of bucolingual and mesiodistal direction to measure the marginal and internal gap. Measurement was carried out by using measuring microscope ($AXIO^{(R)}$) and $I-Solution^{(R)}$ and analysed through the use of ANOVA. Results: As for the mean marginal fitness of the zirconia core, it was $84.74{\pm}27.57{\mu}m$, in $Cerasys^{(R)}$, $80.23{\pm}21.07{\mu}m$ in KaVo $Everest^{(R)}$ and $96.37 {\pm}11.45{\mu}m$ in $LAVA^{TM}$, and as for the mean internal gap, it was $94.11{\pm}30.07{\mu}m$ in $Cerasys^{(R)}$, $92.31{\pm}25.18{\mu}m$ in KaVo $Everest^{(R)}$, and $94.99{\pm}18.74 {\mu}m$ in $LAVA^{TM}$. There was no significant statistically deference among the total average gap of three systems. The internal gap in KaVo $Everest^{(R)}$ seemed to be smaller than $LAVA^{TM}$ (P < .05). The internal gap in the incisal area was larger in all of the three systems. Conclusion: There was no difference in marginal fitness in $Cerasys^{(R)}$, KaVo $Everest^{(R)}$ and $LAVA^{TM}$. As for the internal fitness, it was smaller in KaVo $Everest^{(R)}$ system than $LAVA^{TM}$ system. In all of the three systems, there was a larger gap in incisal area. The marginal and internal gap was within the clinically allowed range in all of the three systems.

• Journal of Food Hygiene and Safety
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• v.28 no.4
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• pp.360-366
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• 2013

The objective of this study is to investigate the effect of multivitamin on macrophage activity in Raw 264.7 cell and repeated oral dose toxicity in Sprague-Dawely rat of multivitamin. Raw 264.7 cells were treated with 50 and $100{\mu}g/mL$ multivitamin for 24 h. To measure the activity of macrophages, NO and TNF-${\alpha}$ assays were performed in Raw 264.7 cells. Treatment with 50 and $100{\mu}g/mL$ multivitamin for 24 h significantly increased production of NO and TNF-${\alpha}$ compared with control groups, indicating activation of macrophages. The female rats were treated with multivitamin of control group, low group (0.24 g/kg), medium group (1 g/kg) and high group (2 g/kg) intragastrically for 4 weeks, respectively. We examined the body weight, the feed intake, the clinical signs and serum biochemical analysis. We also observed the histopathological changes of liver, ovary, brain, adrenal gland, spleen, kidney, heart and lung in rats. No significant differences in body weights, feed intake, biochemical analysis and histopathological observations between control and multivitamin treatment group were found. In conclusion, multivitamin is physiologically safe and improve macrophage activity.