• 제목/요약/키워드: External irradiation

검색결과 240건 처리시간 0.026초

Modelling of effective irradiation swelling for inert matrix fuels

  • Zhang, Jing;Wang, Haoyu;Wei, Hongyang;Zhang, Jingyu;Tang, Changbing;Lu, Chuan;Huang, Chunlan;Ding, Shurong;Li, Yuanming
    • Nuclear Engineering and Technology
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    • 제53권8호
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    • pp.2616-2628
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    • 2021
  • The results of effective irradiation swelling in a wide range of burnup levels are numerically obtained for an inert matrix fuel, which are verified with DART model. The fission gas swelling of fuel particles is calculated with a mechanistic model, which depends on the external hydrostatic pressure. Additionally, irradiation and thermal creep effects are included in the inert matrix. The effects of matrix creep strains, external hydrostatic pressure and temperature on the effective irradiation swelling are investigated. The research results indicate that (1) the above effects are coupled with each other; (2) the matrix creep effects at high temperatures should be involved; and (3) ranged from 0 to 300 MPa, a remarkable dependence of external hydrostatic pressure can be found. Furthermore, an explicit multi-variable mathematic model is established for the effective irradiation swelling, as a function of particle volume fraction, temperature, external hydrostatic pressure and fuel particle fission density, which can well reproduce the finite element results. The mathematic model for the current volume fraction of fuel particles can help establish other effective performance models.

GaAsP 다이오드 조사에 따른 창상치유 효과

  • 김태곤;김영표;이호식;박용필;천민우
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2009년도 추계학술대회 논문집
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    • pp.240-240
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    • 2009
  • We developed the low level laser therapy(LLLT) apparatus for external injury cure using a GaAsP Diode. This equipment was fabricated by using GaAsP diode and a microcontroller, and designed to enable us to control light irradiation timer, and frequency. In this paper, the designed device was used to find out how GaAsP diode light source affects the skin wound of RAT. In the experiment, $1cm^2$ wounds on the External injury of RAT were made. Light irradiation RAT and none light irradiation RAT divided, each RAT was irradiated 20 min a day for 9 days. In result, compared with none light irradiation RAT, the lower incidence of inflammation and faster recovery was shown in light irradiation RAT.

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고 선량률 강내 치료기를 이용한 식도암 치험 1례 (One Case of Esophageal Cancer Treated with High Dose Rate ICR)

  • 김경애;김성규;신세원;김명세
    • Journal of Yeungnam Medical Science
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    • 제5권1호
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    • pp.147-151
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    • 1988
  • 식도암 환자에서 외부 방사선 치료와 고 선량률 강내 치료를 병용하여 자각 증상의 호전은 물론 식도 촬영상에서도 좋은 반응을 보인 환자에서 장기간이 경과후에 발생한 식도 출혈과 식도 기관루를 경험하였기에 문헌 고찰도 함께 하였다

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체외 상처 치유를 위한 4-채널 광 치료기 (4-channel Light Medical Therapy Apparatus for External Injury Cure)

  • 천민우;김성환;소금영;문영래;문성표;박용필;이호식;김태곤
    • 한국전기전자재료학회논문지
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    • 제20권8호
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    • pp.731-735
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    • 2007
  • We developed the 4channel Light Medical Therapy Apparatus for External Injury Cure using a high brightness LED. This equipment was fabricated using a micro-controller and a high brightness LED, and designed to enable us to control light irradiation time, intensity, frequency and so on, Especially, to control the light irradiation frequency, FPGA was used, and to control the change of output value, TLC5941 was used. Control stage is divided into 4 levels by program. Consequently, the current value could be controlled by the change of level in Continue Wave(CW) and the output of a high brightness LED could be controlled stage by stage. Compared with one LED irradiation, several LEDs irradiation could increase optical power.

470nm LED 광이 RAT 피부결손에 미치는 효과 (The effect of 470nm LED Irradiation on skin injury of RAT)

  • 천민우;김성환;박용필;이호식;김영표;김태곤;이희갑
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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    • pp.416-417
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    • 2008
  • This paper performed the basic study for developing the Photodynamic Therapy Equipment for medical treatment. We developed the 4channel light medical therapy apparatus for external injury cure using a LED light source. This equipment was fabricated by using microcontroller, and designed to enable us to control light irradiation timer, intensity and reservation. In this paper, the designed device was used to find out how 470nm LEDs light source affects the skin wound of RAT. In the experiment, $1cm_2$ wounds on the External injury of RAT were made. Light irradiation RAT and none light irradiation RAT divided, each RAT was irradiated one hour a day for 15 days. In result, compared with none light irradiation RAT, the lower incidence of inflammation and faster recovery was shown in light irradiation RAT.

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국소적으로 진행된 갑상선 유두암에서의 방사선치료의 역할 (The Role of External Irradiation for the Locally Advanced Papillary Thyroid Cancers)

  • 김태현;양대식;김철용;최명선
    • Radiation Oncology Journal
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    • 제17권3호
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    • pp.187-194
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    • 1999
  • 목적: 국소적으로 진행된 갑상선 유두암환자에서 수술 후 방사선치료의 성적을 분석하고, 수술과 방사선 동위원소치료를 받은 환자의 치료성적과 비교하여 방사선치료의 효과를 알아보고자 하였다. 대상 및 방법: 본 연구는 1981년 8월부터 1997년 9월까지 국소적으로 진행된 갑상선 유두암(capsular Invasion, extracapsular Invasion or LN metastasis) 환자 91명을 대상으로 하였다. 방사선치료군(23명)의 연령분포는 18세부터 71세였고, 평균연령은 44세였으며, 여자 21명, 남자 2명였다. 원발병소는 주변조직의 침습이 있는 경우(capsular invasion, extracapsular extension)가 22명, 림프절 전이는 16명에서 있었고, 원격전이는 2명에서 있었다. 모든 환자에서 근치적 수술를 시행하였고, 1-125치료는 12명에서 시행하였다. 방사선치료는 Co-60 과 4 MV X-ray를 이용하여 일일선량 $1.8\~2.0$ Gy씩 주 5회 치료하였고 원발병소에 $50\~70$ Gy의 방사선을 조사하였다. 수술과 방사선 동위원소치료군(68명)의 연령분포는 10세부터 74세였고, 평균연령은 43세였으며, 여자 51명, 남자 17명였다. 원발병소는 주변조직의 침습이 있는 경우 51명, 림프절 전이는 45명에서 있었고, 원격전이는 없었다. 모든 환자에서 근치적 수술과 방사선 동위원소치료를 시행하였다. 전체환자의 평균 추적기간은 55.7개월이었다. 결과: 방사선치료군은 국소재발이 2명, 원격전이가 2명(폐전이, 다발성 골전이)에서 있었고, 5년 국소제어율은 $95.2\%$였고, 수술과 동위원소 치료군은 국소재발이 16명, 원격전이가 4명(폐전이) 에서 있었으며, 5년 국소제어율은 $67.5\%$였다. 결론: 국소적으로 진행된 갑상선 유두암 환자에서 방사선치료는 국소재발을 감소시킬 수 있는 효과적인 치료 방법이 될 수 있음을 확인할 수 있었다.

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방사선조사에 의해 피질이형성증 백서의 전기행동학적, 병리조직학적 특징 (Electrobehavioral and Pathological Characteristics in Cerebral Cortical Dysplasia Induced by External Irradiation in the Rat)

  • 최하영
    • Journal of Korean Neurosurgical Society
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    • 제29권7호
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    • pp.861-867
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    • 2000
  • Purpose : Neuronal migration disorder(NMD) is a major underlying pathology of patients with intractable epilepsy. The role of NMD on seizure susceptibility or epileptogenecity, however, has not been documented. Methods : External irradiation of total amount of 250 cGY was performed to the fetal rats on days 16(E16) and 17(E17) of gestation. After delivery, the rats of 230-260g were decapitated for the histopathologic study. Epileptog-enecity of the NMD was studied by observing electroclinical events after intraperitoneal kainic acid(KA) injection in the control rats and NMD rats. Results : Histopathologic findings revealed focal and/or diffuse cortical dysplasia consisting of dyslamination of the cerebral cortex and appearance of the cytomegalic neurons, neuronal heterotopia in the periventricular white matter, dispersion of the pyramidal layer and the dentate gyrus of the hippocampus, and agenesis of the corpus callosum. Abnormal expression of neurofilaments protein(NF-M/H) was characteristically observed in the dysplastic neurons of the neocortex and hippocampus. Early ictal onset and prolonged ictal activity on EEG and clinical seizures were observed from the NMD rats unlike with the control rats. Conclusions : Exteranl irradiation on the fetal rats produced NMD. And the rats with NMD were highly susceptible to kainic acid provoked seizures. This animal model would be useful to study the pathophysiology of clinically relevant NMDs.

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Cobalt-60 gamma 선(線) 외부전신조사(外部全身照射)가 생쥐의 태아(胎兒)에 미치는 영향(影響) (Effects of External Whole-Body gamma-Irradiation on Embryos in Mice)

  • 성재기
    • 대한수의학회지
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    • 제15권1호
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    • pp.9-13
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    • 1975
  • In oder to investigate the effects of cobalt-60 gamma irradiation on the postnatal body gains and the other influece of the pregnant mice were subjected to single whole-body gamma irradiation externally. The results obtained were as follows: 1. The all mice of 400, 600, and 800 Rads gamma-irradiated groups showed abortion after prenatal gamma irradiation within 4 to 9 days. 2. There were significant differences of the postnatal body gains of mice between the control and treated groups (100 Rads and 200 Rads gamma irradiation). 3. The relation between gamma-irradiated doses and the postnatal growth rates of mice were inversly proportional.

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태양광 시스템에서 전압-전류 특성의 일사량 의존성 (Irradiation Dependance of I-V Characteristics of Photovoltaic System)

  • 박세준;황준원;최용성;이경섭
    • 전기학회논문지P
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    • 제58권4호
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    • pp.521-525
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    • 2009
  • Solar, as an ideal renewable energy, has inexhaustible, clean and safe characteristics. However, solar energy is an extreme intermittent and inconstant energy source. In order to improve the photovoltaic system efficiency and utilize the solar energy more fully, and the DC current vary with the irradiation, it is necessary to study the characteristics of photovoltaic I-V according to the external factors. This paper presents the analysis of characteristics of photovoltaic I-V according to the irradiation. The results show that the DC current of the photovoltaic system are increased along with the increasing values of irradiation.

마우스 소뇌과립층의 apoptosis를 지표로 한 진단용 초음파의 안전성 검증 (The evaluation on the biological safety of diagnostic ultrasound using radiation-induced apoptosis in the external granular layer of mouse cerebellum)

  • 오헌;이송은;양정아;조성기;정치영;손창호;김성호
    • 대한수의학회지
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    • 제39권3호
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    • pp.628-634
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    • 1999
  • We have studied, by a nonisotopic in situ end-labeling(ISEL) technique, frequency of apoptosis in the external granular layer(EGL) of the cerebellum of immature mice by ${\gamma}$-rays irradiation from $^{60}Co$ or diagnostic ultrasound exposure. The total number of normal cells and cells showing morphological features of apoptosis were counted. The frequency of apoptotic cells was expressed as a percentage of the total number of cells in EGL. The extent of changes following 200 cGy(1090 cGy/min) was studied at 2, 4, 6, 8, 12, or 24 hours after exposure. The maximal frequency was found 6~8 hours after exposure. The immature mice that received 18, 36, 54, 108, 198, 396 cGy of ${\gamma}$-rays or diagnostic ultrasound(7.5MHz, 4.2mW, $I_{SPTA}=7.9mW/cm^2$, $I_{SPTA}=114.3W/cm^2$) for 10 or 30 minutes were examined 6 hours after irradiation. Measurements performed after ${\gamma}$-ray 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 EGL was y = $(0.1349{\pm}0.01175)D$+$(-0.0001522{\pm}0.0000334)D^2$+0.048($r^2$ = 0.981, D = dose in cGy). In the experiment of ultrasound exposure, the frequency of apoptotic cell was $0.106{\pm}0.130$(10 minutes exposure) and $0.167{\pm}0.220$(30 minutes exposure). We estimated the relative dose of the yield from the experiment with ultrasound by substituting the yield from ultrasound exposure into the curve from the ${\gamma}$-irradiation. The relative dose of ultrasound exposure compared with ${\gamma}$-irradiation were 0.432 cGy(10 minutes exposure) and 0.885 cGy(30 minutes exposure). We have found that there is no evidence to indicate that diagnostic ultrasound involves a significant risk.

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