• Title/Summary/Keyword: 방사선과학

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Evaluation of the Usefulness of Detection of Abdominal CT Kidney and Vertebrae using Deep Learning (딥러닝을 이용한 복부 CT 콩팥과 척추 검출 유용성 평가)

  • Lee, Hyun-Jong;kwak, Myeong-Hyeun;Yoon, Hye-Won;Ryu, Eun-Jin;Song, Hyeon-Gyeong;Hong, Joo-Wan
    • Journal of the Korean Society of Radiology
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    • v.15 no.1
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    • pp.15-20
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    • 2021
  • CT is important role in the medical field, such as disease diagnosis, but the number of examination and CT images are increasing. Recently, deep learning has been actively used in the medical field, and it has been used to diagnose auxiliary disease through object detection during deep learning using medical images. The purpose of study to evaluate accuracy by detecting kidney and vertebrae during abdominal CT using object detection deep learning in YOLOv3. As a results of the study, the detection accuracy of the kidney and vertebrae was 83.00%, 82.45%, and can be used as basic data for the object detection of medical images using deep learning.

Influence of Quaternary Ammonium Anion Exchange Moieties onto Mechanical Properties of Radiation-grafting Anion Exchange Membranes (방사선그라프팅 음이온교환막의 기계적 물성에 대한 4차 암모늄 음이온교환기의 영향)

  • Ko, Beom-Seok;Sohn, Joon-Yong;Shin, Junhwa
    • Journal of Radiation Industry
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    • v.6 no.1
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    • pp.49-54
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    • 2012
  • Various anion exchange membranes were prepared by radiation graft copolymerization of vinylbenzyl chloride onto fluorinated films and subsequent quaternization with various tertiary amines such as trimethylamine, N,N-dimethylbuthylamine, N,N-dimethylaniline, and N-methylpiperidine. The quaternizations of the anion exchange membranes were confirmed by measuring of the ion exchange capacities of the membranes. The mechanical properties and the water uptakes were also measured. The elongation at break was found to be largely dependent on the fluorinated film, the quateranry ammonium, and the degree of grafting. The results indicate that the poly (ethylene-alt-tetrafluoroethylene) with quaternized trimethylamine moiety exhibits higher flexible property compared to the other prepared anion exchange membranes.

Developments in Radiation Health Science and Their Impact on Radiation Protection (방사선 보건과학의 발전과 방사선방호에 미치는 영향)

  • Chang, Si-Young;Kim, In-Gyoo
    • Journal of Radiation Protection and Research
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    • v.23 no.3
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    • pp.185-196
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    • 1998
  • 현재의 방사선방호 원칙과 체계는 국제방사선방호위원회 (ICRP)의 권고에 기반을 두고 있 다. ICRP 의 권고는 대부분 히로시마/나카사키 원폭피해 생존자들에 대한 역학조사 및 수명 연구결과 그리고 관련 방사선생물학 연구결과를 바탕으로 전세계 5개 인구집단(일본, 미국, 푸에리토리코, 영국과 중국)에 대한 방사선위험계수의 예측 및 평가결과에 근거를 두고 있다. 이 저선량 방사선의 (확률적 영향) 위험계수는 인체피폭 방사선량과 그 영향간에는 선형 비례관계가 있으며 영향유발의 문턱값이 존재하지 않는다는 가정인 '선형 무문턱값 선량-영향 모델 (Linear No-Threshold Dose-Effect Model, 이른바 LNT 모텔)' 을 도입하여 유도된 것이다(譯者 밑줄). 그러나 이 LNT 가정의 과학적 근거와 정당성에 대한 비난이 원자력산업계나 일부 과학자들에 의해 제기된 이래, 최근에는 미국 보건물리학회 (HPS)에서 'LNT 가정이 선량과 영향의 관계를 단순화하며 낮은 선량의 위험음 과대평가한다'는 성명서를 발표하기도 했다. 이후 이에 대한 논쟁이 다시 시작되어, 1997 년에 스페인의 Sevill에서는 IAEA와 WHO의 공동주최와 UNSCEAR의 협조로 '저준위 방사선 영향에 대한 국제회의'가 개최되기도 하였으나 아직 어느 쪽에도 유리한 결론이 단정적으로 나지 않았으며, 실질적인 대안이 없는 현실에서 이 LNT 가정은 여전히 방사선방호의 철학적 기초로 남아 있다(譯者 밑줄). 한편, 저선량 방사선의 영향에 대해서는 우리나라에서도 '방사선방어학회, ‘98 년 춘계 심포지움' 및 '원자력학회, '98 년 춘계 학술발표회 워크??????'에서 한양대학교의 이재기 교수에 의하여 소개, 논의된 바 있다.이 논문은 이러한 논의의 후속으로 역자중 일인이 위원으로 있는 OECD/NEA 방사선방호위원회 (CRPPH)가 최근에 ('98.7.) 발간한 보고서를 번역, 주해한 것으로, 과학지식의 진보에 따라 방사선방호분야에서 관심이 되는 주제들에 대한 위원회의 검토의견을 소개하고 있다. 따라서 이 논문이 국내의 방사선방호분야 관계자들에게 최신정보 습득과 지식함양에 좋은 도움이 되기를 기대한다.

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The Inhibitory Potency of Hesperidin on Protein Kinase C Activity Using a Biochip (바이오칩을 이용한 Protein Kinase C의 활성에 대한 헤스페리딘의 저해 효과)

  • Kang, Jung Ae;Rho, Jong Kook;Choi, Mi Hee;Jung, Young Jin;Park, Sang Hyun
    • Journal of Radiation Industry
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    • v.5 no.1
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    • pp.15-20
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    • 2011
  • Protein kinases are the most important drug targets for the treatment of numerous diseases. The involvement of protein kinase C (PKC) in many biological processes such as development, memory, cell differentiation, and proliferation has been demonstrated. PKC is recognized as an important player in carcinogenesis. Thus, a variety of PKC inhibitors have been investigated. Among them, flavonoids have been demonstrated to affect the activity of many mammalian in vitro enzyme systems. The recent investigation was performed to evaluate the inhibitory effects of hesperidin, which is a flavonoid, on the proliferation and carcinogenesis of many cancers. In this study, an efficient kinase assay based on a biochip using radio-phosphorylation was established and performed for an examination of the inhibitory effects of hesperidin on PKC activity at different concentrations of 50, 200, 500 nM. It was found that hesperidin shows inhibitory potency on PKC, and that the biochip can be used to rapidly screen kinase inhibitors resulting in the therapeutic agents.

Effects of Gamma Ray Irradiation on the Struvite Crystallization of Livestock Wastewater (축산폐수를 이용한 스트러바이트 합성에 감마선 조사가 미치는 영향)

  • Yoo, Byeong-Hak;Jo, Seong-Hui;Lee, Myun-Joo;Kim, Tak-Hyun
    • Journal of Radiation Industry
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    • v.4 no.4
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    • pp.313-317
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    • 2010
  • The struvite crystallization was applied to remove $NH_4{^+}$ in livestock wastewater. The ammonium ions can be very toxic to the aquatic creatures. In this experiments, the livestock wastewater from Gongju livestock wastewater treatment plant was used. The behaviors of various parameters such as pH, mole ratio of $Mg^{2+}$ : $NH_4{^+}$ : $PO{_4}^{3-}$ and reaction temperature for struvite crystallization of livestock wastewater and the effect of gamma ray irradiation were evaluated. As results, for the pH variation, the $NH_4{^+}$ removal efficiency showed the highest, 88%, at pH 9~9.25. The removal efficiency of $NH_4{^+}$, $Mg^{2+}$ and $PO{_4}^{3-}$ was showed highest when same molar ratio of $Mg^{2+}$ and $PO{_4}^{3-}$ were applied. The $NH_4{^+}$ removal efficiency showed 82% at $7^{\circ}C$, and 90% at $30^{\circ}C$ with temperature. When the wastewater was irradiated with 20 kGy of gamma ray, $NH_4{^+}$ was removed as much as 83%.

A Study of Interface Layer on CdZnTe Radiation Sensor for Potable Isotope Identifier (이동형 핵종 분석 장치용 CZT 반도체 검출기의 완충전극에 대한 연구)

  • Cho, Yun Ho;Park, Se-Hwan;Kim, Yong Kyun;Ha, Jang Ho
    • Journal of Radiation Industry
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    • v.5 no.1
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    • pp.95-99
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    • 2011
  • The electrical and mechanical properties of electrode for radiation detection are very important. In general, Au electrode and CZT crystal are combined to form ohmic contacts, and the best energy resolution is shown at the Au electrode. The metal contacts are fabricated by electroless deposition method, sputtering deposition method and thermal evaporation method. The electrode fabrication is easy with use of the thermal evaporation method, while an adhesive strength is weak. Thus interface materials such as Ag, Al and Ni were investigated to overcome defects generated by the this method. The thickness of the interface material between the Au electrode and the CZT crystal was 100 Angstroms, the Au electrode with thickness of 400 Angstroms was deposited. The Al+Au electrode is shown that the results of current-voltage and radiation response are similar to results of Au electrode.

Livestock Wastewater Treatment by Zeolite Ion Exchange and Gamma-ray Irradiation (제올라이트와 감마선을 이용한 축산 폐수 처리)

  • Lee, Sang-Ryul;Kim, Tak-Hyun;Lee, Myun-joo
    • Journal of Radiation Industry
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    • v.2 no.1
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    • pp.9-14
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    • 2008
  • Livestock wastewater containing high concentrations of organic matters and ammonia-nitrogen has been known as one of the recalcitrant wastewater. It is difficult to treat by conventional wastewater treatment techniques. This study was carried out to evaluate the feasibility of zeolite ion exchange and gamma-ray irradiation treatment of livestock wastewater. The removal efficiencies of $SCOD_{Cr}$ and $NH_3-N$ were significantly enhanced by gamma-ray irradiation after zeolite ion exchange as a pre-treatment. However, the effects of zeolite particle size on the $SCOD_{Cr}$ and $NH_3-N$ removal efficiencies were insignificant. These results indicate that the combined process of zeolite ion exchange and gamma-ray irradiation has potential for the treatment of livestock wastewater.

The Effects of Electron Beam Irradiation on Thermal and Mechanical Properties of Electrospun Nylon 66 Nano-web (전기방사된 나일론66 나노웹의 열적·기계적 특성에 전자선 조사가 미치는 영향)

  • Jeun, Joon Pyo;Kang, Hyo-Kyoung;Kang, Phil Hyun
    • Journal of Radiation Industry
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    • v.5 no.1
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    • pp.69-73
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    • 2011
  • Polyamide 66 (PA66) nanofibers with Triallyl cyanurate (TAC) were obtained by electrospinning of formic acid and chloroform solution. Electron beam irradiation of PA66 nanofiber with and without TAC was carried out over a range of absorbed doses (20~100 kGy) in nitrogen. The characterization of the irradiated PA66 nanofibers and PA66 nanofibers with TAC was done by scanning electron microscopy (SEM), nuclear magnetic resonance (NMR), thermogravimetric analysis (TGA) and universal testing machine (UTM). The results of the SEM image analysis confirmed that the morphology of PA66 nanofibers was not altered by electron beam. The amount of TAC in PA66 nanofiber with TAC was identified by $^1H-NMR$ analysis. The degradation temperature of PA66 nanofibers with TAC at an absorbed dose of 20~100 kGy was higher than the irradiated PA66 nanofiber without TAC. On the other hand, the decreasing rate of modulus of irradiated PA66 nanofibers with TAC was less than PA66 nanofibers.

Evaluation of Artificial Intelligence Accuracy by Increasing the CNN Hidden Layers: Using Cerebral Hemorrhage CT Data (CNN 은닉층 증가에 따른 인공지능 정확도 평가: 뇌출혈 CT 데이터)

  • Kim, Han-Jun;Kang, Min-Ji;Kim, Eun-Ji;Na, Yong-Hyeon;Park, Jae-Hee;Baek, Su-Eun;Sim, Su-Man;Hong, Joo-Wan
    • Journal of the Korean Society of Radiology
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    • v.16 no.1
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    • pp.1-6
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    • 2022
  • Deep learning is a collection of algorithms that enable learning by summarizing the key contents of large amounts of data; it is being developed to diagnose lesions in the medical imaging field. To evaluate the accuracy of the cerebral hemorrhage diagnosis, we used a convolutional neural network (CNN) to derive the diagnostic accuracy of cerebral parenchyma computed tomography (CT) images and the cerebral parenchyma CT images of areas where cerebral hemorrhages are suspected of having occurred. We compared the accuracy of CNN with different numbers of hidden layers and discovered that CNN with more hidden layers resulted in higher accuracy. The analysis results of the derived CT images used in this study to determine the presence of cerebral hemorrhages are expected to be used as foundation data in studies related to the application of artificial intelligence in the medical imaging industry.