• Journal of the Computational Structural Engineering Institute of Korea
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• v.27 no.4
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• pp.215-222
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• 2014

The objective of this research is to evaluate the seismic performance of steel intermediate moment frames(IMFs) with different heights. The seimic performance is conducted according to ATC-63. Three-, six, nine- and twelve-story IMFs are designed according to KBC 2009. The connection is modeled to have a drift capacity of 0.02rad, which is required for IMF connections. This study shows that the probability of collapse increases with an increase in the height of the frame. Nine- and twelve-story frames did not satisfy the requirement specified in ATC-63.

• The Korean Journal of Nuclear Medicine
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• v.28 no.1
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• pp.124-132
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• 1994

Radioactive iodine has been widely used in patients with thyroid cancer combined with surgical treatment. However, due to individual variations in absorption and excretion and uptake by tumor tissue of radioactive iodine, there are differences in therapeutic effect and adverse effects even if the same doses are administrated. So this study compared the therapeutic effect and radiation hazard by measuring internal radiation dose. Of total 27 patients with well differentiated thyroid cancer who had been thyroidectomized, we administered radioactive iodine 100 mCi, 150 mCi, 200 mCi. According to BEL DOSIMETRY PROTO-COL, beta and gamma ray dose were estimated from a pelt of the logarithm of the percent of dose per liter of whole blood versus day, and percent dose retained versus day using somilogarithmic paper, respectively. 1) Physical dose to whole blood averaged $56.54{\pm}13.02$ rad in 100 mCi administered group, $76.83{\pm}19.97$ rad in 150 mCi administered group, $95.08{\pm}25.51$ rad in 200 mCi administered group and there has been a significant correlation among the groups. 2) Mean percent dose retained 48 hours later was 26.34%. 3) There was no significant correlation of physical dose between absence and presence of metastasis. 4) 17 of 19 patients who has been followed up with TSH and serum throglobulin, Thallium scan were successfully ablated by radioactive iodine. 5) Leukocyte, lymphocyte, neutrophil, platelet counts all deelined in 4.6 weeks and most of all were restored 3 months later. 6) There was no significant correlation between physical dosimetry and biologic dosimetry. Generally administered doses of radioactive iodine (100-200 mCi) to patients with thyroid cancer postoperatively had developed transient bone marrow suppression and minimal chromosomal aberration, but they were within safety dose to blood (200 rad). And there has been no significant differences in residual dose 48 hours later between Korean and western people.

• Radiation Oncology Journal
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• v.2 no.1
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• pp.81-86
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• 1984

The preliminary analysis has been made of 63 Patients who were treated in the Department of Radiation Therapy at Korea University Hospital for the lung cancer from April 1981 to December 1983. The patients were treated via Co-60 teletherapy unit and the doses were 5,400 rad/ 6 week for the curative, $3,600\~4,500\;rad/2\;1/2\;\~3$ week for the Palliative treatment. Thirty two $(32/63=51\%)$ patients have been for curative, $25/63 (40\%)$ were for Palliative, and $6/63 (9\%)$ were for post-operative radiation. A post-radiation treatment, $28/63 (53\%)$ were able to follow from 2 months to 3 yrs. During the follow up, chest X-rays and/or CT scans were taken and $22/27 (81.4\%)$ of patients were responded more than $50\%$ of tumor regression one month following completion of radiation.

• Korean Journal of Remote Sensing
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• v.27 no.2
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• pp.171-180
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• 2011

MAI (multiple aperture SAR interferometry) method has been recently developed to improve the measurement accuracy of along-track surface deformation. By means of split-beam SAR processing, this novel technique produces forward- and backward-looking interferograms, which are combined to generate an MAI interferogram. The along-track surface deformation can then be derived from the MAI interferogram. The achieved accuracy of the along-track surface deformation is approximately 8 cm for interferograms with a coherence of 0.6. It is commonly recognized that the topographic phase on an MAI interferogram can be ignored. However, in this paper, we have generated an MAI interferogram from an ALOS P ALSAR interferometric pair spanning the 2010 Haiti earthquake, and shown that the topographic phase distortion on the MAI interferogram can reach to about $3.45{\times}10^{-4}$ rad./m. This distortion corresponds to an along-track surface deformation of about 98 cm. We have proposed an efficient method to remove the topographic phase distortion. After correcting the distortion, the topographic phase distortion on the MAI interferogram is reduced to about $7.82{\times}10^{-6}$ rad./m. This means that the proposed method can effectively remove the topographic distortion on the MAI interferogram to improve along-track surface deformation measurement.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.13
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• pp.5311-5317
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• 2015

Cigarette smoke derivatives like NNK (4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone) and NNAL (4-(methylnitrosamino)-1-(3-pyridyl)-1-butan-1-ol) are well-known carcinogens. We analyzed the interaction of enzymes involved in the NER (nucleotide excision repair) pathway with ligands (NNK and NNAL). Binding was characterized for the enzymes sharing equivalent or better interaction as compared to +Ve control. The highest obtained docking energy between NNK and enzymes RAD23A, CCNH, CDK7, and CETN2 were -7.13 kcal/mol, -7.27 kcal/mol, -8.05 kcal/mol and -7.58 kcal/mol respectively. Similarly the highest obtained docking energy between NNAL and enzymes RAD23A, CCNH, CDK7, and CETN2 were -7.46 kcal/mol, -7.94 kcal/mol, -7.83 kcal/mol and -7.67 kcal/mol respectively. In order to find out the effect of NNK and NNAL on enzymes involved in the NER pathway applying protein-protein interaction and protein-complex (i.e. enzymes docked with NNK/NNAL) interaction analysis. It was found that carcinogens are well capable to reduce the normal functioning of genes like RAD23A (HR23A), CCNH, CDK7 and CETN2. In silico analysis indicated loss of functions of these genes and their corresponding enzymes, which possibly might be a cause for alteration of DNA repair pathways leading to damage buildup and finally contributing to cancer formation.

• The Korean Journal of Pain
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• v.27 no.2
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• pp.162-167
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• 2014

Background: Although a physician may be the nearest to the radiation source during C-arm fluoroscope-guided interventions, the radiographer is also near the fluoroscope. We prospectively investigated the radiation exposure of radiographers relative to their location. Methods: The effective dose (ED) was measured with a digital dosimeter on the radiographers' left chest and the side of the table. We observed the location of the radiographers in each procedure related to the mobile support structure of the fluoroscope (Groups A, M and P). Data about age, height, weight, sex, exposure time, radiation absorbed dose (RAD), and the ED at the radiographer's chest and the side of the table was collected. Results: There were 51 cases for Group A, 116 cases for Group M and 144 cases for Group P. No significant differences were noted in the demographic data such as age, height, weight, and male to female ratio, and exposure time, RAD and ED at the side of the table. Group P had the lowest ED ($0.5{\pm}0.8{\mu}Sv$) of all the groups (Group A, $1.6{\pm}2.3{\mu}Sv$; Group M, $1.3{\pm}1.9{\mu}Sv$; P < 0.001). The ED ratio (ED on the radiographer's chest/ED at the side of the table) of Group A was the highest, and the ED radio of Group P was the lowest of all the groups (Group A, $12.2{\pm}21.5%$; Group M, $5.7{\pm}6.5%$; Group P, $2.5{\pm}6.7%$; P < 0.001). Conclusions: Radiographers can easily reduce their radiation exposure by changing their position. Two steps behind the mobile support structure can effectively decrease the exposure of radiographers by about 80%.

• The Korean Journal of Pain
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• v.27 no.2
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• pp.145-151
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• 2014

Background: The physician's hands are close to the X-ray field in C-arm fluoroscopy-guided pain interventions. We prospectively investigated the radiation attenuation of Proguard RR-2 gloves. Methods: In 100 cases, the effective doses (EDs) of two dosimeters without a radiation-reducing glove were collected. EDs from the two dosimeters-one dosimeter wrapped with a glove and the other dosimeter without a glove-were also measured at the side of the table (Group 1, 140 cases) and at a location 20 cm away from the side of the table (Group 2, 120 cases). Mean differences such as age, height, weight, radiation absorbed dose (RAD), exposure time, ED, and ratio of EDs were analyzed. Results: In the EDs of two dosimeters without gloves, there were no significant differences ($39.0{\pm}36.3{\mu}Sv$ vs. $38.8{\pm}36.4{\mu}Sv$) (P = 0.578). The RAD ($192.0{\pm}182.0radcm^2$) in Group 2 was higher than that ($132.3{\pm}103.5radcm^2$) in Group 1 (P = 0.002). The ED ($33.3{\pm}30.9{\mu}Sv$) of the dosimeter without a glove in Group 1 was higher than that ($12.3{\pm}8.8{\mu}Sv$) in Group 2 (P < 0.001). The ED ($24.4{\pm}22.4{\mu}Sv$) of the dosimeter wrapped with a glove in Group 1 was higher than that ($9.2{\pm}6.8{\mu}Sv$) in Group 2 (P < 0.001). No significant differences were noted in the ratio of EDs ($73.5{\pm}6.7%$ vs. $74.2{\pm}9.3%$, P = 0.469) between Group 1 and Group 2. Conclusions: Proguard RR-2 gloves have a radiation attenuation effect of 25.8-26.5%. The radiation attenuation is not significantly different by intensity of scatter radiation or the different RADs of C-arm fluoroscopy.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.13 no.1
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• pp.27-34
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• 2020

Human access is restricted to environment where radiation sources are used, however observation equipment should be radiation-resistant as it is exposed. Therefore, if tungsten with the highest specific gravity and melting point and the lowest lead were selected to reduce the dose to the Cobalt 60 radiation source to 1/8, Tu had a volume of 432.6cm3, a thickness of 2.4cm, and Pb had a volume of 961cm3,, a thickness of 3.6cm. By applying this method, produced a radiation resistant CMOS camera with a camera module using a CMOS Image sensor and a radiation shielding structured housing. As a result of applying the head detachable 2M AHD camera (No. ①) that survived the experiment to select the optimal shielding thickness, when shielding the associated equipment such as cameras, adapters, etc. is achieved, it was confirmed that the design of the structure is appropriate by operating well at doses higher than 1.88×106rad. Therefore, it is expected to secure the camera technology and business feasibility that can be applied to high radiation environments.

• Journal of radiological science and technology
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• v.27 no.2
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• pp.35-43
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• 2004

Radioprotective effects of ginseng extracts on liver damage induced by high energy x-ray were studied. To one group of ICR male mice were given white(50 mg/kg/day for 7days, orally) and fermenta ginseng extracts(500 mg/kg/day for 7days, orally) before irrdiation. To another group were irradiated by 5 Gy dose of high energy x-ray. Contrast group were given with saline(0.1 ml). This study also investigated the radioprotective effect between SOD, CAT, hydrogen peroxide and ginseng extracts on hepatic damage. This study measured the level of superoxide dismutase(SOD), catalase(CAT), hydrogen peroxide($H_2O_2$) in liver tissue. Administrating orally white (50 mg/kg/day for 7days, orally) and fermenta ginseng extracts(500 mg/kg/day), the activity of SOD, CAT were generally increased and the hydrogen peroxide($H_2O_2$) was decreased. After irradiation, the activity of SOD, CAT were generally decreased and the hydrogen peroxide($H_2O_2$) was increased. Therefore, ginseng extracts increased antioxidative enzyme activity. And We know that the antioxidatant effect of extracts from white and fermenta ginseng protect radiation damage by direct antioxidant effect involving SOD, CAT. It was included that ginseng can protect against radiation damage through its antioxidatant properties.

• Journal of the Korean Institute of Telematics and Electronics
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• v.27 no.10
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• pp.154-160
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• 1990

System modeling for Heterodyne/Coherent Optical BFSK receiver is described and its receiver performance is evaluated. Receiver performance is deteriorated due to both shot noise and laser phase nois. Therefore, to minimize these noise impacts PLL loop natural frequency is selected optimally. For different power penalty due to phase error, required phase error variance to achieve $BER=10^{-9}$, nomalized loop power, and laser linewidth/bit rate(${\Delta\nu}s/Rb$) are derived. For 0.5dB power penalty, phase error variance=0.035(${rad^2}$), photon numbers=20.0, nomalized loop power = $3.8{\times}10^{-3}$(electron/s per herz), and ${\Delta\nu}s/Rb=5.24{\times}10^{-3}$ are obtained.