• 제목/요약/키워드: Rays

검색결과 2,317건 처리시간 0.025초

Controlling Botrytis elliptica Leaf Blight on Hybrid Lilies through the Application of Convergent Chemical X-ray Irradiation

  • Hong, Sung-Jun;Koo, Tae-Hoon;Yun, Sung-Chul
    • The Plant Pathology Journal
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    • 제32권2호
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    • pp.77-84
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    • 2016
  • X-ray irradiation with convergent chemicals such as nano-silver particles or sodium dichloroisocyanurate (NaDCC) has been used to control leaf blight on cut lilies. The oriental hybrid lily cultivars Siberia, Le Reve, and Sorbonne were irradiated five times by 200 Gy of X-rays in 2014. In 2015, Siberia and Sorbonne were irradiated three times by 150 Gy of X-rays. After artificial infection with Botrytis elliptica on the leaves and petals of cut lilies, this study used convergent chemical X-ray irradiation of 200 Gy or 150 Gy. Leaf and petal blight was measured in terms of incidence and severity at 8 days after infection using total 552 cuttings. Results indicate that the treatments of X-ray irradiation and NaDCC in 2014 and 2015 slightly decreased the severity of petal blight on Siberia and Sorbonne. However, the results were not significant and severity did not decrease as NaDCC concentration increased. Vase-life was observed separately after X-ray irradiation of 270 cut lilies in 2014 and 108 cut lilies in 2015. Chlorophyll content was not affected by either 200 Gy or 150 Gy of X-rays. The number of days of fully opened flowers at Siberia of 150 Gy and Le Revu of 200 Gy increased by 1-2 days. In addition, the relative fresh weights of the X-rayed flowers were 10% drier than the non-irradiated controls. Overall, leaf blight control by X-ray was inferior to the control by gamma rays, and petal color was bleached in Sorbonne and Le Reve cvs. by 150 Gy of X-rays.

The CREAM Experiment in the International Space Station

  • 이직;전진아;이현수;이혜영;임희진;박일흥;;김홍주;박한배;이무현;서은석
    • 천문학회보
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    • 제37권2호
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    • pp.206.1-206.1
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    • 2012
  • The NASA Antarctica balloon experiment CREAM has successfully collected the data of energetic cosmic rays during six flights in past years. It recently observed the unexpected discrete hardening in energy spectra of comic rays. However high-statistics data of energetic cosmic rays are required for the further investigation of the unexpected hardening in comic-ray energy spectra. The International Space Station (ISS) is an ideal platform for the CREAM experiment to investigate the unexpected hardening and explore the fundamental issues like the acceleration mechanism and the origin of energetic cosmic rays because of the high duty cycle of the experiment in the ISS platform. We will present the design of the ISS-CREAM experiment, and the development and fabrication status of the detector components including the 4-layer silicon charge detector which will measure the charge constitution of cosmic rays with unprecedented accuracy.

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투시 검사 시 체위 변화에 따른 입사표면선량의 평가 연구 (An Evaluative Study on ESD(Entrance Surface Dose) by Posture Changes for Fluoroscopy)

  • 양해두;홍선숙;박은성;성민숙;하동윤
    • 대한디지털의료영상학회논문지
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    • 제13권4호
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    • pp.177-183
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    • 2011
  • This study intends to investigate patients' exact exposure doses by comparatively measuring ESD (Entrance Surface Dose) with the DAP meter, which excludes scattered rays, and ESD with the Xi multifunction meter, which includes scattered rays, by posture changes for Esophagography test and UGI test. The materialwere examined through Sonialvision-SafireII SPEC overtube system. ESD was measured by using the DAP meter, and as a tool to measure ESD including scattered rays on the plane of incidence of human phantom, the Xi multifunction meter was used. The average fluoroscopic time of Esophagography test was 4.192 minutes and the average number of images was 47.7, while the average fluoroscopic time of UGI test was 6.881 minutes and the average number of images was 37.8. The ratios of the incident dose of DAP meter and the ESD of Xi meter were calculated bydividing the fluoroscopic time and the number of images by each posture change. As for Esophagography test, the dose increased by 21.6~55.5% in the fluoroscopic test and by 4.8~24.7% in the spot test. In the front spot test, however, the does increased by as little as 5.3%. As for UGI test, the dose increased by 21.1~49.5% in the fluoroscopic test and by 10.1~34.9% in the spot test. It is expected that measuring doses in consideration of scattered rays by posture changes will be an important index in evaluating and managing patients' exact exposure doses for each test above. Furthermore, it is judged that this sort of study is inevitable and desirable to reduce patients' exposure doses after all.

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CZT 반도체 검출기를 활용한 중성자 및 감마선 측정과 분석 기술에 관한 연구 (A Study on the Technology of Measuring and Analyzing Neutrons and Gamma-Rays Using a CZT Semiconductor Detector)

  • 진동식;홍용호;김희경;곽상수;이재근
    • 대한방사선기술학회지:방사선기술과학
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    • 제45권1호
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    • pp.57-67
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    • 2022
  • CZT detectors, which are compound semiconductors that have been widely used recently for gamma-ray detection purposes, are difficult to detect neutrons because direct interaction with them does not occur unlike gamma-rays. In this paper, a method of detecting and determining energy levels (fast neutrons and thermal neutrons) of neutrons, in addition of identifying energy and nuclide of gamma-rays, and evaluating gamma dose rates using a CZT semiconductor detector is described. Neutrons may be detected by a secondary photoelectric effect or compton scattering process with a characteristic gamma-ray of 558.6 keV generated by a capture reaction (113Cd + 1n → 114Cd + 𝛾) with cadmium (Cd) in the CZT detector. However, in the case of fast neutrons, the probability of capture reaction with cadmium (Cd) is very low, so it must be moderated to thermal neutrons using a moderator and the material and thickness of moderator should be determined in consideration of the portability and detection efficiency of the equipment. Conversely, in the case of thermal neutrons, the detection efficiency decreases due to shielding effect of moderator itself, so additional CZT detector that do not contain moderator must be configured. The CZT detector that does not contain moderator can be used to evaluate energy, nuclide, and gamma dose-rate for gamma-rays. The technology proposed in this paper provides a method for detecting both neutrons and gamma-rays using a CZT detector.

Daily adaptive proton therapy: Feasibility study of detection of tumor variations based on tomographic imaging of prompt gamma emission from proton-boron fusion reaction

  • Choi, Min-Geon;Law, Martin;Djeng, Shin-Kien;Kim, Moo-Sub;Shin, Han-Back;Choe, Bo-Young;Yoon, Do-Kun;Suh, Tae Suk
    • Nuclear Engineering and Technology
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    • 제54권8호
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    • pp.3006-3016
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    • 2022
  • In this study, the images of specific prompt gamma (PG)-rays of 719 keV emitted from proton-boron reactions were analyzed using single-photon emission computed tomography (SPECT). Quantitative evaluation of the images verified the detection of anatomical changes in tumors, one of the important factors in daily adaptive proton therapy (DAPT) and verified the possibility of application of the PG-ray images to DAPT. Six scenarios were considered based on various sizes and locations compared to the reference virtual tumor to observe the anatomical alterations in the virtual tumor. Subsequently, PG-rays SPECT images were acquired using the modified ordered subset expectation-maximization algorithm, and these were evaluated using quantitative analysis methods. The results confirmed that the pixel range and location of the highest value of the normalized pixel in the PG-rays SPECT image profile changed according to the size and location of the virtual tumor. Moreover, the alterations in the virtual tumor size and location in the PG-rays SPECT images were similar to the true size and location alterations set in the phantom. Based on the above results, the tumor anatomical alterations in DAPT could be adequately detected and verified through SPECT imaging using the 719 keV PG-rays acquired during treatment.

A field determination method of D-T neutron source yields based on oxygen prompt gamma rays

  • Xiongjie Zhang;Bin Tang ;Geng Nian;Haitao Wang ;Lijiao Zhang ;Yan Zhang ;Rui Chen ;Zhifeng Liu ;Jinhui Qu
    • Nuclear Engineering and Technology
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    • 제55권7호
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    • pp.2572-2577
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    • 2023
  • A field determination method for small D-T neutron source yield based on the oxygen prompt gamma rays was established. A neutron-gamma transport equation of the determination device was developed. Two yield field determination devices with a thickness of 20 mm and 50 mm were made. The count rates of the oxygen prompt gamma rays were calculated using three energy spectra processing approaches, which were the characteristic peak of 6.13 MeV, the overlapping peak of 6.92 MeV and 7.12 MeV, and the total energy area. The R-square of the calibration curve is better than 94% and the maximum error of the yield test is 5.21%, demonstrating that it is feasible to measure the yield of D-T neutron source by oxygen prompt gamma rays. Additionally, the results meet the requirements for field determination of the conventional D-T neutron source yield.

The Next Generation Apartment Model Far Infrared Rays Radiant Heater using Quasi-Resonant Soft Switching PWM Inverter

  • Kwon, Soon-Kurl;Mun, Sang-Pil
    • 조명전기설비학회논문지
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    • 제22권11호
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    • pp.15-22
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    • 2008
  • This paper presents an innovative prototype of a new conceptual electromagnetic induction heated type far infrared rays radiant heating appliance using the voltage-fed quasi-resonant ZVS-PWM high frequency inverter using IGBTs for food cooking and processing which operates under a constant frequency variable power regulation scheme. This power electronic appliance with soft switching high frequency inverter using IGBTs has attracted special interest from some advantageous view points of safety, cleanliness, compactness and rapid temperature response, which is more suitable for consumer power electronics applications.

부석사 조사당 벽화조사에 따른 적외선 T.V카메라 이용 (On the Mural Paintings Detectedc by through the Infrared T.V.Camera at Josadang, Busuk Temple)

  • 정광용
    • 보존과학연구
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    • 통권7호
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    • pp.218-236
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    • 1986
  • In the fields of the cultural properties, the Infrared TV camera is being initiated to use instead of the Infrared photo film fo a better means to detect the description of drawings of the paintings. Seeing from the effect of transillumination, the Infrared TV camera with its long wave of visible spectrum that makes less absorption by the pigments and with the reflection rays passing through the base of colour layers makes it able to findbase drawing and letters. The detection range of transillumination by the infrared rays depends on the kinds of pigments, lines of the base drawing and wave length of the infrared rays. In our country, it was the first time to detect by our Conservation Science Dep't of The Research Institute of Cultural Properties by means of using Infrared TV camera to determine the mural paintings on the Josadang, Busuk Temple, resulted in an epoch-making success, that we have come to know the painting technique methods, how to treat for its conservation and making replica, reproduction, etc.

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제주도 연안에서 처음 출현한 동갈돔과 유어 Apogon semiornatus (First Occurrence of a Juvenile Halfband Cardinalfish, Apogon semiornatus (Apogonidae: Perciformes) from Jeju Island, Korea)

  • 김병직;박태서
    • 한국어류학회지
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    • 제24권3호
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    • pp.227-229
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    • 2012
  • 제주도 연안에서 처음 채집된 동갈돔과 유어 1개체(체장 20.7 mm)를 근거로 Apogon semiornatus를 한국미기록종으로서 기재하였다. 본 종은 등지느러미 기조수 VI-I, 9, 가슴지느러미 기조수 12; 뒷지느러미 기조수 II, 8, 채색은 황적색 바탕으로 체측에 2개의 흑색 사행대가 있는 점에서 국내의 동속 유사종과 쉽게 구별되며, 국명은 '검은두줄붉은동갈돔'으로 명명하였다.

Mass and energy of erupting plasma associated with a coronal mass ejection in X-rays and EUV

  • Lee, Jin-Yi;Raymond, John C.;Reeves, Katharine K.;Moon, Yong-Jae;Kim, Kap-Sung
    • 천문학회보
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    • 제40권1호
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    • pp.85.1-85.1
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    • 2015
  • We investigate the mass and energy of erupting plasma observed in X-rays and EUV, which is associated with a coronal mass ejection (CME) and an X-class flare. The erupting plasma was observed by both the X-ray telescope (XRT) on Hinode and the Atmospheric Imaging Assembly (AIA) on Solar Dynamic Observatory (SDO). We estimate the emission measures of the erupting plasma using a differential emission measure method. The plasma erupts with a loop-like structure in X-ray and EUV. We estimate the mass of erupting plasma assuming a cylinder structure. In addition, we estimate the radiative loss, thermal conduction, thermal, and kinetic energies of the eruptive hot plasma. We find that the thermal conduction timescale is much shorter than the duration of the eruption. This result implies that additional heating during the eruption may be required to explain the hot plasma observations in X-rays.

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