• Title/Summary/Keyword: 자연방사선

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A Study on Neutron Resonance Energy of 180Ta below 1eV Energy (1 eV 이하 에너지 영역에서의 180Ta 동위원소의 중성자공명에 대한 연구)

  • Lee, Samyol
    • Journal of the Korean Society of Radiology
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    • v.8 no.6
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    • pp.287-292
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    • 2014
  • In this study, the neutron capture cross section of $^{180}Ta$(natural existence ratio: 0.012 %) obtain by measuring has been compared with the evaluated data for the capture data. In generally, the neutron capture resonance is defined as Breit-Wigner formula. The formula consists of the resonance parameters such as neutron width, total width and neutron width. However in the case of $^{180}Ta$, these are very poor experimental neutron capture cross section data and resonance information in below 10 eV. Therefore, in the study, we analyzed the neutron resonance of $^{180}Ta$ with the measuring the prompt gamma-ray from the sample. And the resonance was compared with the evaluated data by Mughabghab, ENDF/B-VII, JEFF-3.1 and TENDL 2012. Neutron sources from photonuclear reaction with 46-MeV electron linear accelerator at Research Reactor Institute, Kyoto University used for cross section measurement of $^{180}Ta(n,{\gamma})^{181}Ta$ reaction. $BGO(Bi_4Ge_3O_{12})$ scintillation detectors used for measurement of the prompt gamma ray from the $^{180}Ta(n,{\gamma})^{181}Ta$ reaction. The BGO spectrometer was composed geometrically as total energy absorption detector.

Measurement of MDA of Soil Samples Using Unsuppression System and Compton Suppression of Environmental Radioactivity in Processing Technology (환경 방사능 처리기술에서의 Compton suppression 및 Unsuppression system을 이용한 토양시료의 MDA 측정)

  • Kang, Suman;Im, Inchul;Lee, Jaeseung;Jang, Eunsung;Lee, Mihyeon;Kwon, Kyungtae;Kim, Changtae
    • Journal of the Korean Society of Radiology
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    • v.8 no.6
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    • pp.293-299
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    • 2014
  • Compton suppression device is a device by using the Compton scattering reaction and suppress the Compton continuum portion of the spectrum, so can be made more clear analysis of gamma ray peak in the Compton continuum region. Measurements above background occurs or, radioactivity counts of radioactivity concentration value of $^{40}K$ nuclides $^{137}Cs$ and natural radioactivity artificial radioactivity detected from the surface soil sample, unwanted non-target analysis and interference peak who dotted line you know the calibration of the measurement energy is allowed to apply the (Compton suppression) non-suppressed spectrum inhibition spectrum and (Compton Unsuppression) the background to the measured value of the activity concentration value of the standard-ray source is detected relative to the peak of By measuring according to the different distances cause $^{137}Cs$, and comparative analysis of the Monte Carlo simulation, in order to obtain a detection capability for efficient, looking at the Compton inhibitor, as the CSF value increases with increase in the distance, more It was found that the background due to Compton continuum of the measured spectrum suppression mode Compton unrestrained mode can know that the Compton suppression many were made, using a $^{137}Cs$ is reduced.

APEXOGENESIS OF A DENS EVAGINATUS (하악 소구치에 발생한 치외치의 치근단유도술)

  • Lee, Ji-Min;Choi, Yeong-Chul;Kim, Kwang-Chul;Choi, Sung-Chul
    • Journal of the korean academy of Pediatric Dentistry
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    • v.36 no.2
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    • pp.305-309
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    • 2009
  • Dens evaginatus is a dental anomaly most commonly seen in premolar teeth in which a tubercle or protuberance projects from either the center of the occlusal surface or the buccal triangular ridge. These tubercles are easily fractured from mastication as the tooth erupts and frequently leads to pulp necrosis as a common complication. To prevent these sequelae, prophylactic treatment soon after the tooth starts erupting is essential. These preventive treatments include, selective grinding and protection of the tubercle by pit and fissure sealant. When the tooth does shows signs of pulp necrosis and apical periodontitis, endodontic procedures are needed. Apexification and apexogenesis are usually the treatment of choice for the affected teeth which have immature apices. Apexogenesis is a vital pulp therapy procedure performed to encourage continued physiological development and formation of the root end. It involves removal of the inflamed pulp and the placement of calcium hydroxide on the remaining healthy pulp tissue. This case report describes an atypical apexogenesis of a mandibular premolar which showed to be a dens evaginatus. The tooth which was treated with calcium hydroxide shows good results and is planned for permanent root canal filling.

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The Study on Reduction of Hazardous Materials using Eco-friendly Charcoal Composite Sheet (친환경 활성탄 복합시트의 유해물질 저감 연구)

  • Choi, Il-Hong;Kang, Sang-Sik;Lee, Su-Min;Yang, Seung-Woo;Kim, Kyo-Tae;Park, Ji-Koon
    • Journal of the Korean Society of Radiology
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    • v.12 no.5
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    • pp.615-621
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    • 2018
  • Recently, various environmentally friendly products have been developed for improving the indoor air quality while pursuing a well-being nature-friendly healthy life as a core value. In this research, we not only solve the problems of existing environmentally friendly paints, but also developed a charcoal composite seats that can reduce radon, which is a natural radioactive substance, and evaluated the reduction effect of radon, formaldehyde and volatile organic compounds. In the charcoal composite seats, a sodium silicate emulsion and charcoal were mixed to prepare an charcoal liquid coating material, and the composite seats was fabricated by air-spray coating method. In order to analyze the hazardous substance reduction performance of the fabricated charcoal composite seats, radon was designed to comply with the Ministry of the Environment standard, formaldehyde and volatile organic compounds were designed to comply with KCL-FIR-1085 standard. As a result of the experiment, the fabricated charcoal composite seats was evaluated as having a radon reduction capability of about 90.8% from 20 hours, formaldehyde and volatile organic compounds were 3 hours, and the reduction capability of 96.7% and 96.6% was found respectively. It is considered that these results can be utilized as basic data at the time of product development for improvement of indoor air quality.

A Case of Atypical Pathogen Pneumonia, associated with Recurrent into Diffuse Pneumonic Consolidation (재발성 경과를 취한 비정형 병원균주 폐렴 환자 1예)

  • Oh, Jong-Kap
    • Journal of the Korean Society of Radiology
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    • v.5 no.6
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    • pp.391-400
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    • 2011
  • Pneumonia is an infection of the lungs and respiratory system and can be classified by a variety of factors such as infectious agents, etiology, infection area, and other criteria. From a 46-year-old male, who was suspected of being infected with atypical pathogen pneumonia and underwent such tests as serological testing, examination of sputum, urine examination, parasite examination, bronchoscopy, needle biopsy and so on, no significant abnormality was found. This patient also showed no specific symptoms like auscultatory abnormalities, high fever, nonproductive cough, muscle stiffness, sputum production, dyspnea. Prescription of broad-spectrum oral antibiotics and ant-parasitic didn't seem to be effective against bacterial and atypical pathogen. The patient's condition alternately repeated between natural cure and recurrence. The average healing process during which scarring, nodule recurrence and disappearance on the lungs happened was about 20 days. Chest radiography and chest high resolution computerized tomographic scans(HRCT scan) was performed to depict parenchymal aberrations and demarcate the extent and distribution of atypical pathogen pneumonia. As a result, chest radiography did not show the specific symptoms, whereas areas of opacity (seen as white) which represent consolidation were revealed in chest HRCT scan. This indicates that only chest radiography is not that useful for early diagnosis of atypical pathogen pneumonia in patients, since it can't show exactly what the symptom is because of the barriers such as diaphragm, liver, and spine. Therefore, it is desirable that chest HRCT should be used in the diagnosis to compare with the results of chest radiography. Here, report with literature investigations the case of recurrent atypical pathogen pneumonia.

A study on the relationship between jaw size and tooth size (치아크키와 악골크기의 상관관계에 관한 연구)

  • Ahn, Hyo-Beom;Nahm, Dong-Seok
    • The korean journal of orthodontics
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    • v.33 no.3 s.98
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    • pp.157-167
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    • 2003
  • The purpose of this study was to find whether there is a correlation between tooth size and jaw size. Dental stone models and cephalometric radiographic films of 87 untreated individuals were evaluated. Repeated measurements of the maximum mesiodistal width of the teeth were taken by means of a digital vernier caliper. Linear measurements of jaw size were assessed by means of a digitizer and Visual C++ program. All measurements were taken separately according to the subject's gender. To determine the relationship between jaw and tooth size, the Pearson correlation was used. The results were as follows: 1. Male and female subjects showed a statistical difference in regard to tooth size and jaw size 2. In contrast to the results of the male subjects, there were no statistically significant correlations between maxillary size and maxillary teeth size in female subjects 3. In male subjects, the two maxillary sizes of PTM vert-ANS vert (FH plane) and PTM vert-A yen (palatal plane) were significantly correlated with themaxillary teeth size. Especially, the size of the upper central incisor showed significant correlation with all maxillary sizes. 4. In both male and female subjects, mandibular size B vert- Point J vert (mandibular plane) showed significant correlation with mandibular teeth size. As gleaned kom the results of this study, the relationship between jaw size and tooth size was fair or little in natural occurring good occlusion.

A Radiographic Study on the Horizontal Angle of the Mandibular Condyle in Relation to Temporomandibular Disorders (하악과두의 수평각과 측두하악장애와의 연관성에 관한 방사선학적 연구)

  • Park, Sang-Gyun;Suh, Bong-Jik;Kim, Do-Yun
    • Journal of Oral Medicine and Pain
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    • v.24 no.1
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    • pp.25-36
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    • 1999
  • 저자는 이하두정방사선사진 (願下頭頂放射線寫眞, submentovertex radiographs)을 이용하여 하악과두의 수평각과 측두하악장애와의 연관성을 평가하고자 측두하악장애의 병력 및 증상이 없고, 자연치열로 형성된 정상교합을 가진 성인 34명과 전북대학교병원 구강내과에 내원한 측두하악장애환자 38명을 대상으로, 환자군을 임상검사 및 방사선학적 검사를 통해 편측 정복성 관절원판 전방변위 환자군, 양측 정복성 관절원판 전방변위 환자군 및 편측 비정복성 관절원판 전방변위 혹은 골관절염 환자군으로 세분한 후, 좌우측 외이도의 위치를 확인할 수 있도록 소강구 (小鋼球)가 내재된 장치물을 이용하여 채득한 규격화된 이하두정방사선사진상에서 하악과두의 내측극과 외측극을 이은 선과 양측 외이공에 위치한 소강구를 이은 선으로부터 하악과두의 수평각을 측정하였다. 평가 결과 정상군에서의 좌(평균 25.3도), 우(평균 24.8도)측 하악과두의 수평각 (평균 25.0도)은 유의한 차이를 보이지 않았으며 환자군에서는 이환측 하악과두의 수평각 (평균 28.5도)이 비이환측 하악과두 (평균 26.2도)보다 유의성있게 증가된 수치를 보였다 (p<0.05). 또한 환자군 (평균 27.55도)에서의 하악과두의 수평각이 정상군 (평균 25.0도)에서 보다 유의하게 증가된 수치를 보였다 (p<0.05). 임상적으로 세군으로 구분된 환자군의 경우, 각군의 이환측 또는 비이환측, 각 군을 합한 이환측 또는 비이환측의 경우에 있어서도 정상군에서 보다 하악과두 수평각이 유의성있게 증가된 수치를 보였다 (p<0.05). 세가지로 구분된 환자군 각각의 상호 비교에 있어서는 유의성있는 차이를 나타내지 않았다. 그리고 편측으로 이환된 환자군에서의 이환된 수평각 (평균 29.1도)은 비이환측 (평균 26.2도)보다 유의성있게 증가된 수치를 보였으나 (p<0.05), 양측으로 이환된 환자군에서의 좌우측 수평각은 유의한 차이를 보이지 않았다. 이로써 측두하악장애의 진단 차원에서 측두하악장애를 유발하는 여러 요소 중외 하나로 하악과두 수평각에 대한 평가가 고려되어야 할 것으로 사료된다.

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Study for Valuing of Residential Water when Drought Conditions (가뭄상황시 생활용수 가치 추정)

  • Park, Doo-Ho;Park, Yoon-Shin
    • Proceedings of the Korea Water Resources Association Conference
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    • 2007.05a
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    • pp.487-492
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    • 2007
  • 최근 잦은 기상이변으로 인한 자연재해는 그 빈도와 강도가 점차 증가하고 있다. 이러한 기상이변은 결국, 극단적인 가뭄이 닥칠 가능성이 농후할 것이고, 만일 극단적인 가뭄상황이 도래할 경우 제한급수 또는 절수로 인한 일반인이 느끼는 피해정도는 매우 늘어날 것이다. 본 연구는 가뭄상황시 제한급수를 고려한 소비자의 지불의사를 알아보고자, 7대 특 광역시와 32개 가뭄상습지역에 거주하는 일반인을 대상으로 생활용수 수요패턴과 가뭄상황을 고려한 생활용수의 가치를 추정하였다. 조사결과, 수돗물 수질 관련에 대해서는 가뭄상습지역보다 7대광역시가 더 민감하였고, 수돗물 수량에 대해서는 가뭄상습지역이 더 민감한 것으로 나타났다, 지불의사 추정은 양분선택형과 개방형을 혼합하여 지불의사액을 설문하였고, Tobit모형을 이용하여 지불의사액을 추정하였다. 추정결과, 교육수준이 높을 수록, 가구수가 많을수록, 소득이 높을수록 지불의사가 높은 것으로 나타났다. 또한, 가뭄으로 인해 생활용수의 25% 제한시에는 약 2010원, 50% 제한시에는 2,395원의 추가적인 지불의사가 있는 것으로 추정되었다. 결국, 조사가구의 평균 수돗물 사용량과 절감량등을 추정하여 계산한 결과, 생활용수 25% 제한시 $1m^3$당 추가적인 지불의사 금액은 약 534원으로 추정된다. 지불의사가 기대했던 것보다 낮은 이유는 소비자가 그 정도의 가뭄을 경험하지 못한데서 오는 조세저항으로 여겨진다. 그러나 이 같은 결과는 가뭄을 회피하기 위해 소비자가 기꺼이 지불할 수 있는 비용은 현재의 물 값보다 훨씬 높다는 것을 의미한다. 알 수 있었다.수 없는 실제 방사선작업 환경에서의 선량평가 수행시, 본 논문에서 제시한 선량평가방법을 적용할 경우 계획된 피폭과 예상하지 못한 방사선장에 대한 피폭을 구분할 수 있어 보다 심도 있는 피폭선량평가 및 방사선관리가 가능할 것으로 판단된다.황산기(黃酸基)의 함량은 가장 적었다내고 있었고, in vivo에서는 복강(復腔)(i. p.) 투여(投與)에서는 $12.9{\sim}22.2%$. 경구(經口)(p.o.) 투여(投與)에서는 $11.2{\sim}21.6%$의 높은 활성(活性)을 나타내고 있었다. 단 peroxidase 활성(活性)은 복강(復腔)(i. p.) 투여(投與)에서는 $129.0{\sim}188.6%$, 경구(經口)(p. o.) 투여(投與)에서는 $111.4{\sim}139.6%$의 활성(活性)을 나타내고 있었다.rucic acid를 다량함유(多量含有)하고 있는 목포단교 12는 다른 두 품종(品種)에 비(比)하여 장쇄지방산에 속하는 eicoseuoic acid가 11.7%로 많이 함유(含有)되어 있었다. 그리고 3품종(品種) 모두 중성지질(中性脂質) 획분(劃分)의 지질(脂質)은 전체지방산(全體脂肪酸) 조성(組成)의 비(比)와 별다른 차이(差異)를 나타내지 않았다.수 있으나 본원에서 사용 중인 장비에서 극히 적은 MU의 사용이 현저한 선량적 오차를 유발하진 않는 것으로 사료되어진다. 그러나 정도 관리 시 그 오차를 확인하는 과정은 장비의 사용과 수명에 따라 지속적으로 관리되어져야 할 것이다.>로 평균

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Batch Scale Storage of Sprouting Foods by Irradiation Combined with Natural Low Temperature -V. Cooking Qualities of Irradiated Chestnut after Long-term Storage- (방사선조사(放射線照射)와 자연저온(自然低溫)에 의한 발아식품(發芽食品)의 Batch Scale저장(貯藏)에 관(關)한 연구(硏究) -제5보(第五報) : 장기저장(長期貯藏)된 조사(照射)밤의 조리적성(調理適性)에 대하여-)

  • Yang, Ho-Sook;Kim, Jong-Gun;Cho, Han-Ok;Byun, Myung-Woo;Kwon, Joong-Ho
    • Korean Journal of Food Science and Technology
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    • v.15 no.3
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    • pp.238-244
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    • 1983
  • The cooking quality of irradiated chestnut after longterm storage were evaluated. 1. Color degree and tannin content of irradiated chestnut were slightly increased with the storage, but there was a little difference according to the radiation dose after nine months storage. 2. The main component of free sugars in the irradiated chestnut were identified as sucrose, glucose, fructose and the amino acids of chestnut were identified in the decreasing order of glutamic acid, aspartic acid, leucine, arginine, glycine, alanine, serine, pheylalanine, threonine, valine, isoleucine, tyrosine, methionine and cystein. Free sugars and amino acids of 25 Krad irradiated group showed a little difference compared with those of control group after nine months storage. 3. The calorie of candied chestnut prepared from nine months stored was marked 199 Kcal/100g of edible parts compared with 159 Kcal of raw chestnut. 4. Texture and sensory evaluation of candied chestnut prepared from nine months stored were better in 20-25 Krad irradiated group than in control group.

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Measuring Circuit Design of RI-Gauge for Compaction Control (성토시공관리용 방사성 동위원소 이용계기의 측정회로설계)

  • Kil, Gyung-Suk;Song, Jae-Yong;Kim, Ki-Joon;Whang, Joo-Ho;Song, Jung-Ho
    • Journal of Sensor Science and Technology
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    • v.6 no.5
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    • pp.385-391
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    • 1997
  • An objection of this study is to develop a measuring circuit of a gauge using radioisotope for compaction control. The gauge developed in this study makes use of radioisotope with the activity exempted from domestic atomic law and consists of measuring circuits for gamma-rays and thermal neutrons, a high voltage supply unit, and a microprocessor. To obtain meaningful numbers of pulse counts, parallel five and two circuits are provided for gamma-rays and thermal neutrons, respectively. Being simple in electrical characteristics of G-M detector for gamma-rays, pulses are counted through only a shaping circuit. Very small pulses generated from He- 3 proportional detector for thermal neutrons are amplified to the maximum of 50 [dB] and a window comparator accepts only pulses with meaning. To minimize effects of natural environmental radiation and electrical noise, circuits are electrostatically shielded and pulses made by ripples are eliminated by taking frequency of high voltage supplied to the circuit and pulse height of ripples into consideration. One-chip microprocessor is applied to process various counts, results are stored and the gauage is made capable to communicate with PC. Enough and meaningful numbers of pulses are counted with the prototype gauage for compaction control.

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