• The Korean Journal of Nuclear Medicine Technology
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• v.13 no.3
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• pp.86-91
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• 2009

Purpose: The whole body scan in Nuclear Medicine is a widely accepted examination and procedure. Especially, it is mainly used in bone, I-131, MIBI, and HMPAO WBC scans. The diverse uses of the whole body scan range from the HMPAO WBC scan with a speed of 13cm/min, to a whole body bone scan using the Onco. Flash technique with a speed of 30cm/min. The accuracy of table movement has a strong correlation with the image quality, and inaccuracy of speed could negatively affect the image quality. The purpose of this study is to evaluate the accuracy of the table movement while considering the influence of the age of the equipment and the variability in the weight of the patients. Material and Methods: The study was conducted using two of Seoul Asan Medical Center's SIEMENS gamma cameras which are commonly used in our whole body study. The first one is the oldest gamma camera, an ECAM plus (installed in 2000), and the last is brand new one, a SYMBIA T2 (installed in 2008). Three trials were conducted with the tables moving at a different speed each time; 10, 15 and 30 cm/min. The tables' speeds were measured by checking how long it took for the table to move 10cm, and this was repeated every 10cm until the table reached 100 cm. With an average body weight of the patients of about 60~70 kg, the table speed was measured with weights of 0 kg, 66 kg and 110 kg placed on the table, then compared among conditions. Results: The coefficient of variance (CV) of the ECAM plus showed 1.23, 1.42, 2.02 respectively when the table movement speeds were set at 10, 15, and 30 centimeters per minute. Under the same conditions, the SYMBIA T2 showed 1.23, 1.83 and 2.28 respectively. As table movement speed more, the variance of CV as the speed increases. When the patient body weight was set to 0, 66 and 110kg, the CV values of both cameras showed 0.96, 1.45, 2.08 (0 Kg), 1.32, 1.72, 2.27 (66 Kg) and 1.37, 1.73, 2.14 (110 Kg). There was no significant difference (p>0.05) in 95 percent of confidence intervals and measured CV values were acceptable. However, the CV value of the SYMBIA T2 was relatively larger than the ECAM plus. Conclusion: The scan speed of the whole body scan is predetermined based on which examination is being performed. It is possible for the accuracy of the speed to be affected, such as the age of the equipment, the state of the bearings or the weight of a patient. These factors can have a negative impact on the diagnostic consistency and the image quality. Therefore, periodic quality control should be needed on the gamma cameras currently being used, focusing on the table movement speed in order to maintain accuracy and reproducibility.

• Fire Science and Engineering
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• v.27 no.1
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• pp.39-45
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• 2013

This study analyzes the explosion hazard of dry cleaning solvent recovery machine in laundry shop in two aspects, i.e. combustible and ignition source, and determines the explosive conditions of this machine by conducting mockup explosion tests repeatedly, varying conditions and using real dry cleaning solvent recovery machines. As to combustibles, two kinds of combustibles used widely in Korea have been selected and tested. The flash points, LEL's, and saturation vapor pressures of those combustibles have been measured, and their explosion specific curves have been drawn, based on the results of the measurements, so that the explosion risks of those materials may be determined, depending on the temperatures. Potential voltages generated from materials for laundry and foreign materials of metals have been assumed to be the ignition sources in this application, and their potential voltages have been measured, depending on temperature, humidity, and antistatic agent, by using real materials for laundry and a potential voltage measuring device. Tests have been conducted, varying the quantities, concentrations, and operating temperatures of materials for laundry. As a result, explosions have not been generated with potential voltages of materials for laundry, but explosions have been observed when applying artificial spark energy of 2.0 mJ.

• Composites Research
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• v.12 no.3
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• pp.75-83
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• 1999

The thermal properties of carbon/phenolic and silica/phenolic ablative composites were investigated by measuring the heat capacity, thermal diffusivity and thermal conductivity. The heat capacities of carbon/ phenolic and silica/phenolic composites were calculated from differential scanning calorimeter curve. The thermal diffusivities of carbon/phenolic and silica/phenolic composites were measured by the laser flash method with varying laminated direction, i.e., with laminar direction and across laminar direction. The thermal diffusivities decreased with increasing temperature. The thermal conductivities of carbon/phenolic and silica/phenolic composites were calculated using the heat capacity, density and thermal diffusivity. The thermal conductivities increased with increasing temperature. The thermal conductivity of with laminar direction is two times higher than that of across-laminar direction in carbon/phenolic composite due to the directionality of thermal conductivity of carbon fiber. The thermal conductivities of two dimensional fiber reinforced composites were analyzed using the conductivities of constituents and volume fraction of each constituent. The thermal conductivities of carbon fiber and silica fiber were calculated from thermal conductivities of carbon/phenolic and silica/phenolic composites. The thermal conductivities of carbon/phenolic and silica/phenolic composites at RT were predicted from thermal conductivities of fiber and resin with varying the volume fraction of fiber.

• 한국지구과학회:학술대회논문집
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• 2005.02a
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• pp.203-212
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• 2005

The purpose of this study was to develop e-learning contents and to examine how ICT-powered instruction using the developed e-learning contents affects the science achievements of students and how the students respond to that. After an experiment in the 7th class of the weather condition unit in high school earth science, e-learning contents were prepared by using the videotaped material and flash animation to teach key learning points. The selected two different classes, experimental and control groups, shows almost the same final scores in the first semester. The experimental group received ICT-powered instruction with the contents developed in the study, and the control group received a typical expository lesson. And then the achievement test was done to these two groups, separately. The major findings of the study were as follows: As for the effects of ICT-powered instruction on the academic achievement, the average scores of the experimental group is higher than that of the control group, but the difference is insignificant. When each group was subdivided into the upper and lower groups, the upper group got higher average scores and the difference was significant. But there was no significant disparity between the lower groups. Therefore, the ICT-powered instruction using the e-learning contents gives a good effect on the students whose levels are higher than the average. In the questionaike about the ICT instruction, they generally had a positive opinion about its impact on learning interest and class participation and its learning effects.

• The Journal of Korean Obstetrics and Gynecology
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• v.32 no.4
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• pp.132-143
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• 2019

Objectives: The purpose of this study is to provide basic information on Korean medical research and treatment through analysis of breast cancer patients, who visited ${\bigcirc}{\bigcirc}$ university Korean medicine hospital. Methods: To analyze characteristics of breast cancer patients who visited korean medicine hospital, we searched medical records from January 1, 2016 to May 13, 2019, and 86 breast cancer patients were analyzed. Results: 1. The general characteristics of the subjects are as follows. The average age was $47.65{\pm}9.62years$ and 40's was the most (46.51%). The average height was $159.78{\pm}4.91cm$ and the average weight was $57.29{\pm}9.34kg$. The average body mass index (BMI) of the patients was $22.40{\pm}3.50kg/m^2$. 2. The stage distribution record indicated stage０ (9.72%), stageI (31.94%), stageII (34.72%), stageIII (20.83%) and stageIV (2.78%). 14 patients with unknown stage were excluded. 3. Before coming to the korean medicine hospital, of the 86 patients, 72 (83.72%) patients received surgical therapy, 55 (63.95%) patients received chemotherapy and 44 (51.16%) patients received radiotherapy. 11 (12.79%) patients chose oriental medicine as their primary treatment option. 4. The mean duration from diagnosis to hospital visit was $13.87{\pm}15.53months$. Among the total 86 patients, 46 (53.49%) patients visited for symptom relief during the follow-up period. 5. The most common symptom was general weakness in 29 (33.72%) patients, followed by hot flash, myalgia, insomnia, digestion disorder, numbness, edema, arthralgia, operation site pain, cold sensation and mastalgia. 6. Among 86 patients, 55 (63.95%) patients received acupuncture and moxibustion together. The most prescribed herbal medicine to subjects was Sibjeondaebo-tang-gamibang and Cheonhye-dan (25%). Conclusions: These results could be helpful to provide basic data on the Korean medical approach of breast cancer patients.

• Journal of the Korean Geographical Society
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• v.41 no.1 s.112
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• pp.106-120
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• 2006

Natural or man-made disaster has been expected to be one of the potential themes that can integrate human geography and physical geography. Typhoons like Rusa and Maemi caused great loss to insurance companies as well as public sectors. We have implemented a natural disaster management system for a private insurance company to produce better estimation of hazards from high wind as well as calculate vulnerability of damage. Climatic gauge sites and addresses of contract's objects were geo-coded and the pressure values along all the typhoon tracks were vectorized into line objects. National GIS topog raphic maps with scale of 1: 5,000 were updated into base maps and digital elevation model with 30 meter space and land cover maps were used for reflecting roughness of land to wind velocity. All the data are converted to grid coverage with $1km{\times}1km$. Vulnerability curve of Munich Re was ad opted, and preprocessor and postprocessor of wind velocity model was implemented. Overlapping the location of contracts on the grid value coverage can show the relative risk, with given scenario. The wind velocities calculated by the model were compared with observed value (average $R^2=0.68$). The calibration of wind speed models was done by dropping two climatic gauge data, which enhanced $R^2$ values. The comparison of calculated loss with actual historical loss of the insurance company showed both underestimation and overestimation. This system enables the company to have quantitative data for optimizing the re-insurance ratio, to have a plan to allocate enterprise resources and to upgrade the international creditability of the company. A flood model, storm surge model and flash flood model are being added, at last, combined disaster vulnerability will be calculated for a total disaster management system.