• 제목/요약/키워드: EM2

검색결과 1,154건 처리시간 0.041초

Characteristics of Specific Absorption Rate (SAR) in Electromagnetic (EM) Dosimetry

  • Hwang, Sun-Tae;Choi, Kil-Oung
    • Journal of Radiation Protection and Research
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    • 제25권2호
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    • pp.109-114
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    • 2000
  • The SI unit of specific absorption rate (SAR) in W/kg in the electromagnetic (EM) field as non-ionizing radiation is exactly same as the SI unit of absorbed dose rate in Gy/s in the ionizing radiation field. The SI unit of both physical quantities can be expressed in $[m^{\cdot}s^{-3}]$. Where, the unit of absorbed dose, Gy stands for Gray. In EM biological interactions, the SAR equations are derived and the characteristics of EM field energy absorption in terms of the SAR are discussed and described on the mathematical basis.

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Pattern Analysis and Performance Comparison of Lottery Winning Numbers

  • Jung, Yong Gyu;Han, Soo Ji;kim, Jae Hee
    • International Journal of Internet, Broadcasting and Communication
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    • 제6권1호
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    • pp.16-22
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    • 2014
  • Clustering methods such as k-means and EM are the group of classification and pattern recognition, which are used in management science and literature search widely. In this paper, k-means and EM algorithm are compared the performance using by Weka. The winning Lottery numbers of 567 cases are experimented for our study and presentation. Processing speed of the k-means algorithm is superior to the EM algorithm, which is about 0.08 seconds faster than the other. As the result it is summerized that EM algorithm is better than K-means algorithm with comparison of accuracy, precision and recall. While K-means is known to be sensitive to the distribution of data, EM algorithm is probability sensitive for clustering.

Multi-Messenger Astronomy with GECKO, Gravitational-wave EM Counterpart Korean Observatory - Past, Present, and Future

  • Im, Myungshin
    • 천문학회보
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    • 제44권2호
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    • pp.35.3-35.3
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    • 2019
  • The new era of multi-messenger astronomy (MMA) has arrived in 2017 with the detection of the binary neutron star merger in both gravitational wave (GW) and electromagnetic radiation (EM). Now, the new run of GW detectors are providing numerous GW events and the number GW events are expected to increase dramatically in future as the GW sensitivities improve. When the GW studies are combined with EM counterpart observations, a great synergy is expected in many areas of study such as the physical process following the compact object merger, the environment of such events (and galaxy evolution), and cosmology, Therefore, it has now become crucial to identify and characterize these GW events in optical/IR EM. In the past, we have been performing optical/NIR observation of GW events using a worldwide network of more than 10 telescopes, and are getting more actively involved in MMA of GW sources. In this talk, we will present our network of telescopes, the EM follow-up observation results of GW events including GW170817 and the O3 events in 2019, and the current issues in MMA. We will also give the future prospects of MMA, showing the forecast for the GW events and the outlook of EM MMA observations.

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브라질 실용 포어에 미친 아프리카어의 어휘적 영향 (A Influência de Vocabulários de Origem Africana em Uso no Português Brasileiro)

  • 김한철
    • 이베로아메리카
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    • 제13권1호
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    • pp.1-39
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    • 2011
  • O presente estudo tem como objetivo principal analisar a influência de vocabulários de origem africana em uso no português brasileiro(PB). A fim disso, observamos os tipos e as características das línguas africanas. E ainda, para compreender a situação atual de uso desses termos no Brasil, apresentamos um panorama do registro dos vocábulos de origem africana no PB, e organizamos os vocabulários em três categorias, especialmente, nos registros dos séculos XIX e XX. Em primeiro, a categoria 1 pode ser usada em qualquer interação social, contrastando com as outras duas categorias. Em segundo, a categoria 2 é constuída de termos informais, de uso coloquial que, eventualmente, dependendo da situação, são substituídos por outras. Por último, a categoria 3 é de termos marcadamente informais, de uso restrito. Através disso, comparamos os registros anteriores com os dados obtidos da nossa pesquisa. Com os resultados, podemos reconhecer a estabilidade e o dinamismo do uso desses termos hoje no PB.

아토피 피부염 유사 NC/Nga 마우스 모델에서 유용 미생물 발효물질의 항염증효과 (Anti-inflammatory Effects of Effective Microorganism Fermentation Substance on Atopic Dermatitis-like NC/Nga Mouse Model)

  • 목지예;정승일;조정근;최지원;남상윤;장원길;문병은;박광현;장선일
    • 동의생리병리학회지
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    • 제24권2호
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    • pp.258-265
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    • 2010
  • Atopic dermatitis (AD) is a chronically relapsing pruritic inflammatory skin disease. To find new anti-inflammatory products for skin inflammatory disease such as AD and contact dermatitis, we produced the effective microorganism fermentation substance (EM-S) by fermentation of medicinal plants with effective microorganisms including photosynthetic bacteria, lactic acid bacteria and yeast, screened the effects of EM-S on NC/Nga model mice. Murine AD-like skin lesions were made by painting Dermatophagoides farinae (Df) extract. Topically applied EM-S significantly reduced clinical severity score, ear thickness and histological grade in AD-like NC/Nga mouse model by Df antigen sensitization. In addition, the serum IgE and Th2 chemokine levels (TARC/CCL17, MDC/CCL22 and CTACK/CCL27) were significantly reduced by EM-S. Futhermore, skin tissue expressions of Th2 chemokines were significantly reduced by EM-S. These results demonstrate that topical application of EM-S may be improve the AD-like skin lesion by suppressing IgE and Th2 chemokines.

순환모형에 대한 EM 알고리즘의 초기값 선정방법의 개선 (An improvement on initial value selection in applying an EM algorithm for recursive models)

  • 정미숙;김성호
    • 응용통계연구
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    • 제12권2호
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    • pp.433-447
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    • 1999
  • 검사관련 능력과 문항점수사이의 관계를 모형화하기 위해 사용한 순환모형에서 관측불능인 능력상대변수를 비롯한 모든 변수들이 범주형 변수라 가정하자. 이 범주형 자료를 위한 모수추정문제를 다루기 위해 EM 방법을 이용했는데, EM 방법은 사용하기에 편리하지만 순환모형에 대한 추정값이 적절하지 않는 경우가 발생한다. 그 주된 원인중의 하나로 초기값 선정의 잘못을 들 수 있는데, 본 논문에서는 이 외에 구조상의 결함도 그 원인이 됨을 경험적으로 보았다. 따라서 구조적 결함을 먼저 해결하면 보다 효과적인 초기값을 선정할 수 있으리가 기대한다.

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충돌방지레이더의 허상방지용 전파흡수제에 관한 연구 (A Study on the EM Wave Absorber for Eliminating False Images in Collision-Avoidance Radar)

  • 최창묵;임봉택;안용운
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2008년도 춘계종합학술대회 A
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    • pp.117-120
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    • 2008
  • 본 논문은 차량 충돌방지 레이더의 허상방지용 전파흡수체를 유전손실재료인 $TiO_2$을 이용하여 개발하였다. 먼저 전파흡수체 샘플을 유전손실재료인 $TiO_2$ 와 바인더인 CPE를 사용하여 조성비별 제작하고, 네트워크 아날라이저를 이용하여 측정한 5-parameter로부터 1-Port Method를 이용하여 복소비유전율을 계산하였다. 그리고 계산된 복소비유전율을 이용하여 전파흡수체를 설계 및 제작한 결과 조성비 $TiO_2$:CPE=70:30 wt.%, 두께 1.85 mm, 주파수 76-77 GHz에서 20 dB 이상의 전파를 흡수하는 전파흡수체를 개발하였다.

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Total Phenolic Compounds and Flavonoids in the Parts of Artichoke (Cynara scolymus L.) in Viet Nam

  • Thi, Bui Ha Thu;Park, Moon-Ki
    • 한국환경과학회지
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    • 제17권1호
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    • pp.19-27
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    • 2008
  • Artichoke extracts are widely used alone or in association with other herbs for embittering alcoholic and soft drinks and to prepare herbal teas or herbal medicinal products in Viet Nam. The objective of this paper was a screening of flavonoids and total phenolic compounds content in the parts of artichoke (Cynara scolymus L.) as flowers, leaves, roots, trunks, stumps, The total phenolic compounds and flavonoids in the parts of artichoke were extracted among 3 extraction methods as methanol extraction (EM1), mixing methanol and water method (EM2) and water extraction method (EM3). Total phenolic compounds and flavonoids were determined by UV/VIS, HPLC techniques. The apigenin 7-O-glucosides, cynarin, narirutin, gallic acid, caffeic acid were found as the main flavonoids constituents in all parts of artichoke. It showed that value of total phenolic compounds and flavonoids by EM3 were higher than that of total phenolic compounds and flavonoids by EM1 and EM2. Furthermore, the results of this study revealed that total phenolic compounds and flavonoids, obtained by these convenient extraction methods, may show the quick efficacy of artichoke in all respects of their quality and quantity.

세침흡인 검체의 전자현미경 검색으로 진단된 전이성 악성 흑색종 1예 (Electron Microscopic Study on Fine Needle Aspiration Cytology of Metastatic Malignant Melanoma)

  • 이동화;진소영;권계현
    • 대한세포병리학회지
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    • 제3권2호
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    • pp.82-89
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    • 1992
  • Electron microscopy (EM) can provide a valuable contribution to light microscopy (LM) In the Interpretation of fine needle aspiration cytology (FNAC) specimen, especially in the diagnosis of the tumor. However, considerable care in processing the specimen is mandatory to recover the cells and avoid altering the fine structures. We experienced a case of malignant melanoma in 33-yrs-old female, diagnosed by EM study of FNAC specimen from the axillary mass, who was initially thought as disseminated carcinomatosis on LM study. The technique of EM study on FNAC specimen consisted of washing the needle and syringe in 2.5% glutaraldehyde after a rapid stain (Diff-Quik), which was used to obtain a preliminary diagnostic impression and to assure the adequacy of the EM specimen. After centrifugation in the steps of fixation and dehydration, the sediment was made into an epon block and examined. The whole processing time of EM study can be shortened within 7 or 8 hours, and results can be available within 48 to 72 hours. Our experience suggests the EM study on FNAC can be a useful diagnostic method in the diagnosis of difficult FNAC cases.

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색조영상에서 랜덤결측화소값 대체를 위한 EM 알고리즘 기반 기법 (An EM Algorithm-Based Approach for Imputation of Pixel Values in Color Image)

  • 김승구
    • 응용통계연구
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    • 제23권2호
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    • pp.305-315
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    • 2010
  • 본 논문에서는 색조영상의 R-, G-, B-성분에서 랜덤결측된 화소값들의 대체를 위한 프리퀀티스틱(frequentictic) 기법을 제공한다. 이 기법은 관측영상을 가우시안 마코프 랜덤필드 상의 실현치로서 가정하고, 주어진 화소 내의 근방 화소들이 에지 강도에 따른 서로 다른 분산을 가지는 정규분포를 따른다고 설계함으로써 에지에서 결측화소 대체값이 이질적 색상에 영향 받지 않도록 한다. 이러한 모형하에서 우도가 최대화하도록 결측화소값들을 근사 EM 알고리즘에 기반 한 방법으로 모수들을 추정하고 결측화소를 대체한다. 제안된 방법의 결과들은 보간법에 기초한 대체법과 비교하여 그 유효성을 보인다.