• Proceedings of the Korean Nuclear Society Conference
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• 2005.05a
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• pp.411-412
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• 2005

There are some differences as a result of comparison between internal and external standard method. Thin-film XRD was used to measure the thin damaged layer by proton irradiation. Experiment was performed by external standard method to measure bulk sample accurately. A little changes of crystallite size and lattice parameter by small dose were observed. X-ray penetrates too deeply above damaged layer of graphite despite of small X-ray incident angle.

• The Journal of Korean Society for Radiation Therapy
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• v.3 no.1
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• pp.11-18
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• 1989

Brachytherapy is known to be a good modality to achieve local control as a boost treatment following limited external irradiation, which may reduce the external beam related complication particularly in head and neck cancer. The authors developed iridium-192 ribbons recently to replace the radium needles in the field of brachytherapy. Total of 48 cases of head and neck and pelvic-perineal cancer patients had been treated with Ir-192 ribbons during last two years from October 1986 to September 1988, and the results were analyzed to assess the applicability of the fabricated sources. The conclusion is as follows; 1. Iridium implant resulted excellent tumor control effect in clinical application. 2. Iridium is superior than radium and cecium in brachytherapy because of easier to use and lesser exposure to the personnel. 3. Afterloading technique is useful to modify dose distribution, to expand treatment site and method, and to develop interstitial hyperthermia.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.910-913
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• 2002

We have achieved an improved stability of an analog electro-optic effect in FLC/polymer composite films. The optimization of device depends on both the composition of the FLC/polymer mixture and the energy of UV irradiation. This device exhibits continuous gray scales and the mechanical stability against external forces.

• Korean Journal of Veterinary Research
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• v.38 no.4
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• pp.679-685
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• 1998

We have studied, by a nonisotopic in situ DNA end-labeling (ISEL) technique, frequency of apoptosis in the external granular layer (EGL) of the cerebellum after whole-body irradiation of newborn mice and intestinal crypt cell of adult mice by gamma-rays from $^{60}Co$. The extent of changes following 2 Gy(10.9 Gy/min) was studied at 2, 4, 6, 8, 12, or 24h after exposure. The maximal frequency was found 4-8h after exposure. The mice that received 0.18, 0.36, 0.54, 1.08, 1.98, or 3.96 Gy were examined 6h after irradiation. Measurements performed after irradiation showed a dose-related increase in apoptotic cells in each of the mice studied. The dose-response curves were analyzed by a linear-quadratic model; frequency(%) of apoptotic cell in the newborn mice cerebellum was ($13.49{\pm}1.175$)D+$(-1.52{\pm}0.334)D^2$+0.048($r^2=0.981$, D = dose in Gy) and frequency(number per crypt) of apoptotic cell in the intestinal crypt of adult mice was ($3.857{\pm}0.420$)D+$(-0.535{\pm}0.120)D^2$+0.155($r^2=0.952$, D = dose in Gy). It provides the basis required for a better understanding of results which will be obtained in any further studies for biological responses of radiation using newborn and adult mice.

• Journal of Yeungnam Medical Science
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• v.6 no.2
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• pp.103-111
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• 1989

The object of this study was to determine the radiation effect on the urinary bladder and to establish the basic data for optimal fraction schedule on the whole abdominal irradiation of the mice. Although radiation damage of the urinary bladder is one of the dose-limiting factor for treatment of lower abdominal cancer, such as uterine cervical or rectal cancer, systematic histopathological study of total dose and recovery duration is very rare, especially in conventional fractionation regimen of clinical use. Authors used 198 mice and analyzed histopathological findings according to total dose(40 & 50GY) and recovery duration(1-15 weeks after completion of irradiation). The results were summarized as follows : 1. No definite difference of radiosensitivity was noted between male and female group. 2. Most of mucosal injuries were recovered within 14 weeks in 40 GY irradiated group. 3. Vascular injury and change of connective tissue were prominent and persisted even mild degree until 15 weeks after completion of irradiation in 50 GY irradiated group. 4. Although follow up duration of this study(105 days) was not enough to compare life span of mice, this study emphasized that precious schedule for treatment planning was necessary for preventing or reducing of later complication.

• Journal of radiological science and technology
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• v.18 no.2
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• pp.75-86
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• 1995

Embryos and fetuses are more sensitive to various environmental agents than adults of children biological effects following the exposure, such as intrauterin, malformation, have intimate conception with the prenatal exposure. There have been many studies on radiation and other agent. However, imformation about the ultrasound effects is limited. It is very important to study the effect of ultrasound with these kinds of fatera in consideration of ultrasound protection and safty. In this study, embryonic and fefal effects of ICR mouse embryos irradiated on 24, 48, 12 and 192 hpc of preimplantation and organogenesis period at the intensity of $0.5{\sim}3\;W/cm^2$ were investigated. Many type of external malformation observed in mouse irradiated on 72 hpc and 192 hpc. However, the embryos irradiated on 24 hpc and 48 hpc, at witch embryos had less then 6 cells and were pre-compaction stage, had no sensitivity for external malformation. The threshold doses of external malformation in mouse irradiated on 72 hpc and 192 hpc, at which embryos were consisted of $16{\sim}32$ cells and neural formation stage, were $1\;W/cm^2$ and $0.5\;W/cm^2$.

• Journal of the Korea Institute of Military Science and Technology
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• v.17 no.2
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• pp.197-203
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• 2014

In this paper, the effect of unsteady radiation on the horizontal fin of an external fuel tank by flame of a flying flare was analysed to see the temperature increase of the fin and the thermal impact on the fin. Radiation between two surfaces was calculated using the concept of radiation resistance of surface and space including radiation, irradiation and shape factor for two flying trajectories of a flare, maximum temperature of 2200 K, emissivity of 0.95, flying velocity of 30 m/s, and thermal surface area of $0.01m^2$. The result shows that the temperature increase of the fin is 0.236 K, and the thermal effect on the fin is ignorable. And it was found that temperature is increased a little because small amount of heat energy can be radiated due to the short exposure time to the heat source.

• Radiation Oncology Journal
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• v.8 no.2
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• pp.231-239
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• 1990

From May 1979 through December 1981 a total of 524 patients with carcinoma of the uterine cervix were treated by radiation therapy with curative intent. Among the 524 patients, 350 were treated with a high-dose-rate (HDR), remote-controlled, afterloading intracavitary irradiation (ICR) system using a cobalt source (Ralstron), and 168 patients received a low-dose-rate (LDR) ICR using a radium source. External beam irradiation with a total dose of 40-50 Gy to the whole pelvis followed by intracavitary irradiation with a total dose of 30-39 Gy in 10-13 fractions to point A was the treatment protocol. ICR was given three times a week with a dose of 3 Gy per fraction. Five-year actuarial survival rates in the HDR-ICR group were $77.6{\%}$ in stage IB (N=20), $68.2{\%}$ in stage II (N=182), and $50.9{\%}$ in stage III (N=148). In LDR-ICR group, 5-year survival rates were $87.5{\%}$ in stage IB (N=22), $66.3{\%}$ in stage II (N=91), and $55.4{\%}$ in stage III (N=52). Survival rates showed a statistically significant difference by stage, but there was no significant difference between the two ICR groups. Late bowel complications after radiotherapy were noted in $3.7{\%}$ of the HDR-ICR group and $8.4{\%}$ of the LDR-ICR group. There was no severe complication requiring surgical management. The incidence of bladder complications was $1.4{\%}$ in the HDR-ICR group and $2.4{\%}$ in the LDR-ICR group. The application of HDR-ICR was technically simple and easily performed on an outpatient basis without anesthesia, and the patients tolerated it very well. Radiation exposure to personnel was virtually nil in contrast to that of LDR-ICR. Within a given period of time, more patients can be treated with HDR-ICR because of the short treatment time. Therefore, the HDR-ICR system is highly recommended for a cancer center, particularly one with a large number of patients to be treated. In order to achieve an improved outcome, however, the optimum dose-fractionation schedule of HDR-ICR and optimum combination of intracavitary irradiation with external beam irradiation should be determined through an extensive protocol.

• The Journal of the Korean bone and joint tumor society
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• v.5 no.1
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• pp.9-16
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• 1999

A new method of limb sparing by resection, extracorporeal irradiation and reimplantation has several theoretical advantages. This method preserves the mobility of a joint and avoids the problem of loosening or breakage of tumor prosthesis. This study involved using extracorporeal irradiated autogenous joint transplantation for reconstruction after en bloc resection, and observed the periods of functional union and histological changes in irradiated tissue of the knee joint. This study also aimed to clarify whether the degeneration of articular cartilage is induced in rabbits by a single 50Gy dose of irradiation at the knee joint. Twenty New Zealand rabbits about three kilograms were randomized into two groups of 10 rabbits each. In group 1, as control, we resected the knee joint followed by reimplantation without irradiation. Group 2 received extracorporeal irradiation on the resected knee joint followed by reimplantation. Following are the results of these observations. The osteotomy site showed external callus formation in the roentgenographic finding eight weeks after reimplantation. There was marked degenerative changes in the collagen fiber of the irradiated anterior cruciate ligament and meniscus during the fourth week, but new blood-vessel formation was observed in the vicinity. There was degenerative changes in the collagen fiber of articular cartilage treated extracorporeal irradiation at four and eight weeks in the scanning electron micrographic findings. These findings was in contrast to those of subchondral bone which showed decreased cellularity and empty lacuna at four and eight weeks. Autoradiography demonstrated active [$^3H$]uridine incorporation by irradiated chondrocyte at eight weeks after reimplantation. These results indicate that when destruction of the articular cartilage and soft tissue of the knee joint is not severe, extracorporeal irradiation and reimplantation can be used with several advantage in maintaining movement of the joint while avoiding problems of tumor prosthesis and rejection, and therefore extracorporeal irradiated autogenous joint transplantation can be used as a limb-sparing procedure for temporary biological spacer in the childhood bone tumor around the knee.

• Korean Journal of Veterinary Research
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• v.13 no.1
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• pp.85-102
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• 1973

In the event a population of animals is exposed to ionizing radiation, proper disposition of animals will minimize loss to the farmer and protect the public from unwholesome meat and dairy products. Clinical response is an important factor in considering salvage of animals for food following exposure to ionizing radiation whether the dose is lethal or not. It is the purpose of this report to present the discussions of blood picture and growth of y ung growing rabbits exposed to cobalt-60 gamma-irradiation. The experimental animals were Hyrnalayan rabbits of 65 days old. The body weight for all animals of the time of irradiation was approximately 450g. The 96 rabbits used in the experiment were allotted t groups of eight. Rabbits in one group served as controls and the others were exposed to single doses of 100, 200, 300, 400, 500, 600 and 700 Roentgens (R). The exposure does rate averaged 15 R per minute. Central blood was obtained by heart puncture. Erythrocyte and leukocyte enumerations and, determinations of hemoglobin in blood and hematocrit value were made in the usual manner. Erythrocyte counts, concentrations of hemoglobin in blood, and hematocrit readings dropped to the lowest value between 1 and 4 weeks postirradiation, returning towards the control values. But recovery was not complete at the time of the last determination on 6 weeks postirradiation. There was a progressive decrease with increasing radiation does in the above values. Mean corpuscular volume, mean corpuscular hemoglobin and mean corpuscular hemoglobin concentration were not affected by the irradiation. After irradiation of each does the numbers of total leukocyte and the absolute numbers of various types of white cell began to decrease rapidly, and reached a minimum after 2 weeks, returning towards normal levels. But recovery was not complete at the time of the last determination on 6 weeks postirradiation. The reductions in total leukocyte and differential counts as the radiation does increases were apparent. Relative neutrophilia was observed in each irradiated group because of more expense of lymphocytes after irradiation. Growth rate of the rabbits was not affected by 100 R of whloe-body irradiation, while rabbits irradiated with 200, 300, 400 and 500 R showed marked depression of growth rate. As the radiation does increases, a depression of growth rate was apparent. The rabbits exposed to 600 and 700 R ceased from growing and recovery was not recognized during the experimental period.