• Title/Summary/Keyword: alpha track

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Chemical Methods Used in Petrological Analysis of Koongarra Uranium Ore Samples in ASSAR Natural Analogue Program

  • Park, Yong-Joon;Pyo, Hyung-Ryul;Kim, Ji-Young;Kim, Won-Ho
    • Nuclear Engineering and Technology
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    • v.30 no.6
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    • pp.518-530
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    • 1998
  • A natural analogue study has been performed for the Koongarra uranium ore deposit in Australia as an international agreement of the Analogue Studies in the Alligator Rivers Region (ASARR). Rocks obtained from the Koongarra deposit, Northern Territory of Australia, were examined in order to understand uranium migration processes of primary and secondary ore-body in both weathered and unweathered zones. Total alpha activities of rock samples were measured to compare the relative amount of uranium in the sample. Uranium distributions have been investigated by means of both the alpha-autoradiography and the fission track registration technique after irradiation in a flux of thermal neutrons (~10$\times$$10^{13}$nㆍ$cm^{-2}$ㆍs$^{-1}$) for 2 minutes. The mineral phases corresponding to the registered alpha-tracks and fission tracks were identified by petrological observation with optical microscope as well as X-ray diffraction and electron microprobe analysis (EPMA). Uranium was found mostly inside of the fracture of the quartzite and its mineral phase was identified as sklodowskite. The mineral phase associated with high uranium concentration was found as illeminite by petrological observation with optical microscope as well as EPMA.

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Comparison of Indoor Radon Concentrations in Areas of Jeollabuk-do Province (전라북도 일부지역의 라돈 농도 비교 연구)

  • Yoo, Juhee;Lee, Kyusun;Seo, Sooyun;Kim, Seonhong;Lee, Jeongsub
    • Journal of Environmental Health Sciences
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    • v.45 no.6
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    • pp.658-667
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    • 2019
  • Objective: This study was designed to compare construction types and seasonal radon concentrations in dwellings in Jeollabuk-do Province in Korea. Methods: The measurement of indoor radon concentrations in 79 dwellings using alpha-track detectors was performed every three months (seasonally) over one year between 2015 and 2016. Also, Radon concentrations in soil were measured in spring to investigate the correlations between the concentrations in soil and indoor air. Results: The annual average concentration of indoor radon for dwellings was 89.7±72.1(GM: 72.4) Bq/㎥, with a range (min-max) of 17.2 to 505.4 Bq/㎥. The highest indoor radon concentration was measured in winter and the lowest was shown in summer. The geometric mean of radon concentration in winter was 1.03-2.58 times higher than other seasons. Radon concentrations in soil were investigated at the depth of 1 m, and the concentrations ranged from 1,780 Bq/㎥ to 123,264 Bq/㎥. This showed low correlations with indoor radon concentrations.

Cytotoxicity of Diesel Exhaust Particles from Various Vehicles toward Macrophage Cells (국내 디젤 차량 배기 입자가 쥐 대식세포에 미치는 세포독성 평가)

  • Lee, Jang-Han;Lee, Yong-Kwon;Lee, Ji-Young;Lee, Seung-Bok;Kim, Sun-Hwa;Bae, Gwi-Nam;Lee, Hak-Sung;Lim, Cheol-Soo;Chung, Nam-Hyun
    • Environmental Analysis Health and Toxicology
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    • v.25 no.2
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    • pp.111-120
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    • 2010
  • DEPs (diesel exhaust particles) like any other particles can be also inhaled into lung to participate in a damaging reaction to the organ. Possible damages might be apoptosis and inflammatory responses to the cells in respiratory track. The aim of this study was cytotoxicity evaluation of DEPs from five in-use diesel vehicles using a murine macrophage cell (RAW 254.7). We found that most DEPs have a considerable cytotoxicity compared to the control and SRM 2975. When measured by MTT assay and extents of apoptosis, DEPs of two highmileage vehicles had higher toxicity than those of the other three low-mileage vehicles tested. Although mRNA expression level of TNF-${\alpha$ somewhat explains the trend of cytotoxicity and apoptosis, that of IL-1$\beta$ did not. Correlation studies among the extents of MTT assay, apoptosis, and TNF-$\alpha$ expression showed that the extents between apoptosis and TNF-$\alpha$ expression was most highly correlated (r=0.96). These results suggest that cytotoxicity of various DEPs could be compared easily by measuring the extent of apoptosis or TNF-$\alpha$ expression by DEPs.

Comparative studies of various transfection processes for the optimal luminescence signal analysis (최적의 luminescence 신호 분석을 위한 유전자 전달 방법의 비교연구)

  • Park, Seohyun;Lee, Sunghou
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.11
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    • pp.640-647
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    • 2016
  • By minimizing fluorescence interference phenomena, aequorin-based luminescence technology can provide a relatively sensitive detection platform with integration of $G{\alpha}16$ protein in order to track internal calcium mobilization by G protein-coupled receptors (GPCR). In this type of cell-based functional assay format, it is essential to optimize the transfection process of a receptor and $G{\alpha}16$ protein. For this study, corticotropin releasing factor receptor subtype 2(CRF2) was set as a model system to generate three stable cells with CRF2 and $G{\alpha}16$ in addition to transiently transfected cells under three different conditions. Agonist (sauvagine) and antagonist (K41498) responses in those cells were analyzed to develop the optimum transfection process. As a result, the effective signal ratio in the dose response experiments of sauvagine and K41498 were at least 10-fold higher (z'=0.77) in CRF2-$G{\alpha}16$ stable cells. For the transient transfection cells, stable expression of $G{\alpha}16$ prior to the CRF2 represented a two-fold higher signal (z'=0.84) than the other cases of transient transfection. In conclusion, for the utilization of transient transfection processes to develop a cell-based GPCR functional assay system, it is suggested to introduce various target receptors after stable expression of $G{\alpha}16$ protein.

Poststructural Curriculum and Topic-centered Framework of The New Science Curriculum (후기 구조주의 교육과정과 새 과학과 교육과정의 주제 중심 내용 구성)

  • Kwak, Young-Sun;Lee, Yang-Rak
    • Journal of the Korean earth science society
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    • v.28 no.2
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    • pp.169-178
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    • 2007
  • In this research we diagnosed the actual status of the 7th National science elective curriculum and suggested a way to select and organize the content of the new science elective curriculum. The first science education reform was grounded in the structuralism where the structure of discipline was valued above everything else. On the other hand, the second science education reform suggested alternative interpretations of students' opportunity to learn, putting a brake on the structuralist thinking. According to the survey result, the majority of the science elective courses are in need for revision because the contents are overcrowded, too difficult in light of students' learning readiness, failed to draw students' interest in science, and are overlapped and repeated among the 10th grade science, high school science I and II. In particular, Earth Science II and physics II are the most unfavorable courses among students. Thus, we recommended a fundamental change be made in the new curriculum in addition to the optimization of the content. In this paper, we suggested 'topic-centered content organization' for the science elective course I, i.e., Physics I, Chemistry I, Biology I and Earth Science I that is designed for both science track and non-science track students. Since curriculum provides students with an 'opportunity to learn', a curriculum study should focus on what the 'opportunity to learn' is that students ought to be offered. Based on the result of this study, we recommended one way to select and organize the content of high school elective curriculum.

Kogan's Attitude Toward Old People: Evaluation of validity and reliability assessment among nursing students in Thailand, Myanmar, and Indonesia

  • Runkawatt, Viliporn;Kerdchuen, Kanyanat;Tipkanjanaraykha, Kitsanaporn;Ubolwan, Kanyarat;Tawetanawanich, Yadchol;Nasirin, Chairun;Win, Mar Lar
    • Asian Journal for Public Opinion Research
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    • v.3 no.3
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    • pp.145-155
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    • 2016
  • Background: Asia is on track to become the region with the most elderly people in the world. The elderly population will reach 922.7 million by the middle of this century. Therefore, they will be cared for by the today's youth. Negative attitudes toward older people can make adolescents more uncomfortable relating to them. Objectives: The objective of this study was to evaluate validity and reliability of Kogan's attitude toward old people among nursing students in Thailand, Myanmar, and Indonesia. Methods: Content validation of the 34-item Kogan's attitude toward old people was examined by three geriatric nursing experts. The reliability was evaluated on 600 nursing students, from nursing colleges in Thailand (200), Myanmar (200), and Indonesia (200). Findings: The attitude scores towards the elderly ranged from 34 to 238. All of the 34 items were found to have significant item-to-total correlations (p< .05). The reliability results were as follows: In Thailand, Cronbach's alpha was .70 for the total scale, .72 for the positive scale, and .68 for the negative scale. In Myanmar, Cronbach's alpha was .68 for the total scale, .65 for the positive scale, and .66 for the negative scale. In Indonesia, Cronbach's alpha was .66 for the total scale, .71 for the positive scale, and .72 for the negative scale. Conclusions: These findings suggest that Kogan's attitude toward old people is reliable and valid for nursing students from Thailand, Myanmar, and Indonesia. However, Kogan's attitude toward old people should be revised by these countries, including changing wording on all items for better reliability. The revised version must then be tested for reliability and validity.

GUI Environmental Controller Design with USB IF (USB IF를 이용한 GUI환경의 제어기 개발)

  • Sun-Hag Hong
    • Journal of the Korea Computer Industry Society
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    • v.4 no.4
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    • pp.449-454
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    • 2003
  • In this paper, GU environmental controller is implemented with USB(Universal serial bus) IF(interface). Especially, the performance examination of ultrasound diagnostic device which connects external USB port with front panel is automatically inspected by VC++ examination program. The test program minimizes the operation of inspector with making the examined result audible or visible, and maximizes the productivity of custom device. The GUI environmental controller controls a standard keyboard, a track ball with dedicated buttons to emulate a standard two-button mouse, switches, rotary encoders, an analog potentiometer group, two alpha-numeric displays. and a touch screen; all of which generate events for the host.

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A Study on the implementation of Visual Object Tracking Using Exemplar Transformer in the Embedded System (임베디드 시스템에 Exemplar Transformer를 활용한 시각적 객체 트래킹 구현에 관한 연구)

  • Do-Wan Kim;Chae-Yeon Lim;Chae-Won Lee;Hae-Kyung Moon
    • Proceedings of the Korea Information Processing Society Conference
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    • 2024.05a
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    • pp.621-622
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    • 2024
  • 본 논문은 Exemplar Transformer를 활용하여 단일 프로세서 환경에서 동작하는 시각적 객체 추적(Visual Object Tracking) 모델인 ETTrack(Exemplar Transformer Track)을 리눅스(우분투 20.04) 운영체제를 사용하는 임베디드 시스템 라떼판다 알파(LattePanda Alpha)에 탑재하였다. 데스크톱 프로세서인 Intel i7-8700와 라떼판다 알파의 Intel m3-8100y에서의 객체 추적 성능과 속도를 AUC(Area Under the ROC Curve)와 FPS를 통해서 비교평가하였다. 평가 결과 기존 트랜스포머 기반 추적 모델(TransT)과 유사한 성능, 3 FPS 빠른 추적 속도를 나타내는 것을 구현 증명하였다.

A Kinetics Study of Rn Daughter and Atmospheric Trace Gas Using Alpha Track Detection (알파비적검출방법에 의한 대기중 라돈딸핵종의 화학적 동특성연구)

  • Yoon, Suk-Chul;Ha, Chung-Woo
    • Journal of Radiation Protection and Research
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    • v.20 no.2
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    • pp.79-83
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    • 1995
  • A number of investigators have reported formation of radiolytic ultrafine particles produced by the interaction of ionizing radiation with atmospheric trace gases. Previous studies have suggested that a very high localized concentration of the hydroxyl radical produced by the radiolysis of water can react with atmospheric trace gases such as $SO_2$ and produce lower vapor pressure compounds that can subsequently nucleate. To determine the trace gas and water vapor concentration dependence of the active, positively charged, first decayt product of radon (Po-218), a well-controlled radon chamber was used in this research. The mobility spectrum of the decay products in the range of $0.07-5.0cm^2/V\;sec$ from the radon chamber was measured using alpha track detector installed inside a specially-designed electrostatic spectrometer. Measurements were taken for different concentrations (0.5ppm to 5ppm) of $SO_2$ in Purified, Compressed air. A kinetics Study following the clustering of $SO_2$ around the $PoO_x^+$ ion in an excess of $SO_2$ for interpretation of the reaction processes was performed.

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A Study on the Concentrations of Indoor Radon for Houses in Chungcheongbuk-do Province, Korea (충청북도 일부지역 내 주택 실내 라돈 농도)

  • Ji, Hyun-A;Yoo, Ju-Hee;Kim, Ga-Hyun;Won, Soo Ran;Kim, Seonhong;Lee, Jeongsub
    • Journal of Environmental Health Sciences
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    • v.45 no.6
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    • pp.668-674
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    • 2019
  • Objectives: Modern people spend most of their day indoors. As the health impact of radon becomes an issue, public interest also has been growing. The primary route of potential human exposure to radon is inhalation. Long-term exposure to high levels of radon increases the risk of developing lung cancer. Radon exposure is known to be the second-leading cause of lung cancer, following tobacco smoke. This study measures the indoor radon concentrations in detached houses in area A of Chungcheongbuk-do Province considering the construction year, cracks in the houses, the location of installed detectors, and seasonal effects. Methods: The survey was conducted from September 2017 to April 2018 on 1,872 private households located in selected areas in northern Chungcheongbuk-do Province to figure out the year of building construction and the location of detector installed and identify the factors which affect radon concentrations in the air within the building. Radon was measured using a manual alpha track detector (Raduet, Hungary) with a sampling period of longer than 90 days. Results: Indoor radon concentrations in winter within area A was surveyed to be 168.3±193.3 Bq/㎥. There was more than a 2.3 times difference between buildings built before 1979 and those built after 2010. The concentration reached 195.4±221.9 Bq/㎥ for buildings with fractures and 167.2±192.4 Bq/㎥ for buildings without fractures. It was found that detectors installed in household areas with windows exhibited a lower concentration than those installed in concealed spaces. Conclusion: High concentrations of indoor radon were shown when there was a crack in the house. Also, ventilation seems to significantly affect radon concentrations because when the location of the detector in the installed site was near windows compared to an enclosed area, radon concentration variation increased. Therefore, it is considered that radon concentration is lower in summer because natural ventilation occurs more often than in winter.