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The 105-month Swift-BAT all-sky hard X-ray survey

  • Oh, Kyuseok;Koss, Michael;Markwardt, Craig B.;Schawinski, Kevin;Baumgartner, Wayne H.;Barthelmy, Scott D.;Cenko, Bradley;Gehrels, Neil;Mushotzky, Richard;Petulante, Abigail;Ricci, Claudio;Lien, Amy;Trakhtenbrot, Benny
    • The Bulletin of The Korean Astronomical Society
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    • v.43 no.1
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    • pp.36.3-37
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    • 2018
  • We present a new catalog of hard X-ray sources detected in the first 105 months of observations with the Burst Alert Telescope (BAT) on board the Neil Gehrels Swift observatory. The 105 month Swift-BAT survey is a uniform hard X-ray all-sky survey performed in the 14-195 keV band. The Swift-BAT 105 month catalog provides 1632 (422 new detections) hard X-ray sources in the 14 - 195 keV band above the 4.8 sigma significance level. Adding to the previously known hard X-ray sources, 34% (144/422) of the new detections are identified as Seyfert AGN in nearby galaxies (z < 0.2). The majority of the remaining identified sources are X-ray binaries (7%, 31) and blazars/BL Lac objects (10%, 43). As part of this new edition of the Swift-BAT catalog, we release eight-channel spectra and monthly sampled light curves for each object in the online journal and at the Swift-BAT 105 month Web site.

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Effect of Ca-doping on the superconducting properties of Nd-Ba-Cu-O bulks (Nd-Ba-Cu-O 벌크 초전도체의 초전도 특성에 미치는 Ca 첨가계의 영향)

  • 이훈배;위성훈;유상임
    • Progress in Superconductivity and Cryogenics
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    • v.4 no.1
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    • pp.21-25
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    • 2002
  • The effect of Ca-doping on the superconducting properties of Nd-Ba-Cu-O bulk superconductors, fabricated by the oxygen-controlled melt growth process, has been systematically investigated. Various c-axis textured bulk samples were grown using precursors with the nominal compositions of $Nd_{1.8-x}Ca_{x]Ba_{2.4}Cu_{3.4}O_{y}$ (x= 0.00, 0.02, 0.05, 0.10, 0.15) in a reduced oxygen atmosphere of 1%O$_2$ in Ar. Magnetization measurements revealed that the critical temperatures(Tc) were almost linearly depressed from 95K to 86K with increasing the Ca dopant from x : 0.0 to 0.15, respectively, and thus critical current densities(Jc) at 77K and for H//c-axis of specimens were gradually degraded with increasing x. Compositional analyses revealed that although the amounts of the Ca dopant both in $NdBa_2Cu_2O_y(Nd123) and Nd_4Ba_2Cu_2O_{10}(Nd422)$,/TEX> were increased with increasing x, only less than half of the initial Ca compositions were detected in melt-grown Ca-doped Nd-Ba-Cu-O bulk crystals. The supression of Tc is attributed to an increased Nd substitution for the Ba site in the Nd123 superconducting matrix with increasing the amount of the Ca dopant.

Studies on Quality of Silage form Domestic Herbage III. Effects of starch addition on the quality of Kudzu silage (야초 사일리지의 품질향상에 관한 연구 III. 칡 사일리지에 있어서 전분첨가효과)

  • 김종쾌;황태기;김대진
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.10 no.1
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    • pp.48-54
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    • 1990
  • In order to investigate effects of starch addition on the fermentative quality and dry matter digestibility (DMD) of Kudzu, Puerarie thunbergii Bentham plants were ensiled by the conventional method in small experimental plastic silo of 7.5 liter with different levels of starch addition. The fermentative quality, neutral detergent fiber (NDF), acid detergent fiber (ADF), and acid detergent lignin (ADL) of silage were determined by chemical analysis, and in vitro dry matter digestibility (DMD) by pepsin-cellulase technique. Total digestibile nutrients (TDN), digestible energy (DE) and metabolizable energy (ME) were calculated with DMD. The results obtained were as follows; 1. Acetate, butyrate, PH, NDF, ADF, and ADL of Kudzu silage were reduced with increasing of starch addition but the contents of lactate and total acid were increased. 2. The DMD was marked 47.5, 49.5, 51.2, 57.9 and 62.0 % under starch addition with a rate of 0, 2, 4, 6 and 8 %, respectively. 3. TDN, DF and ME were increased with high rate of starch addition. 4. The regression equation and correlation of Kudzu silage between level of starch (X) and DMD (Y) were Y= 41.6 + 1.86 X (I= 0.96, P < 0.01), of silage between Flieg's score (X) and DMD (Y) were Y= 41.6 + 0.23 X (I= 0.96, P < 0.01) and of silage between level of starch (X) and Flieg's score (Y) were Y= 21.3 + 7.97 X (I= 0.97, P < 0.01), respectively.

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Enhanced-xVSB System Development for Next Generation Terrestrial DTV RF Transmission (차세대 지상파 DTV 전송시스템 개발)

  • Kim, Sung-Hoon;Lee, Jae-Youn;Lee, Soo-In;Ahn, Chie-Teuk;Kim, Ki-Doo
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2006.11a
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    • pp.187-190
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    • 2006
  • In this paper, we describe a new 1/4 rate robust modulation techniques for Enhanced-x VSB system which is fully backward compatible with ATSC 8-VSB standard. 1/4 rate mode Enhanced-xVSB system provides broadcasters with a wide choice of trade-offs of data rate vs amount of robustness of enhanced data for pedestrian/mobile services. Lab test results of proposed Enhanced-xVSB 1/4 rate mode robust stream are a significantly improved multipath as well as AWGN reception performance for Enhanced-xVSB receiver. We suggest an Enhanced-xVSB terrestrial broadcasting system for ATSC HDTV and pedestrian/portable TV simultaneous broadcasting service providing.

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Second locus for late-onset familial Amyotrophic Lateral Sclerosis (가족성 근위축성측삭경화증을 유발시키는 두 번째 유전자 위치)

  • 홍성출
    • Journal of Life Science
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    • v.11 no.3
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    • pp.279-283
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    • 2001
  • Amyotrophic lateral sclerosis(ALS) is a progressive neurologic disorder resulting from the degeneration of upper and lower motor neurons, and is inherited in 10% of cases. About 20% of familial ALS, clinically indistinguishable from sporadic ALS, is caused by mutations of Cu/Zn superoxide dismutase on chromosome 21q22.21 inherited as an autosomal dominant trait. We now report a new locus in the non-SOD1 dominantly inherited ALS. We screened a large ALS family with 11 affected individuals and one obligate gene carrier with genome-wide ABI polymorphic markers using the ABI 377 automated system. No evidence of linkage was obtained with the autosomal markers. We next screened this family with X chromosome markers as there was no evidence of male-to-male tran-smission of the disease. Linkage was established with several X chromosome markers with a lod score up to 3.8; almost the maximum possible score in this family. Our finding imply that a gene for the dominant expression of a neuronal degeneration is coded on X chromosome and raise the question of the role of X-linked genes that escape inactivation in this pathogenesis. More importantly, our finding that a gene causing ALS is localized on X-chromosome has direct investigational relevance to sporadic ALS, where epidemiological studies show male gender predominance(1.3:1) and earlier onset in men by 5-10 years.

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RESTORATION OF RADIATION INJURY BY GINSENG EXTRACT II (인삼에 의한 방사선 손상 회복효과)

  • Yonezawa M.;Takeda A.;Katoh N.
    • Proceedings of the Ginseng society Conference
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    • 1984.09a
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    • pp.133-140
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    • 1984
  • 인체가 방사선에 의해 손상을 받게 되면, 실제적으로 치료, 회복시킨 수 있는 물질은 아직 발견되지 않았다. 이에 저자는 720R의 X-선을 조사시킨 mice에 Oura 등의 방법에 따라 부분 정제한 인삼 추출물을 투여하여 X-선 손상으로부터의 회복능을 검정하였다. 주사한 인삼 추출물의 용량에 의존적으로 30일간의 생존율이 증가하였다. Saline을 주사한 대조군과 인삼 추출물을 주사한 실험군 사이의 생존율의 차이는, 동물 한 마리당 1.8mg을 투여한 실험에서 조차 통계학적으로 유의성을 보였다. (P<0.001) 550R의 X-선을 조사시킨 mice에 인삼 추출물을 투여하면 적혈구와 혈소판의 양적 회복이 촉진되었다. 또한 인삼 추출물중 열에 안정한 분획이 비장이 비대하여지는 것과 같은 부작용이 없어 방사선의 손상으로부터 보호 효과가 있음을 알았다. 이 분획은 mice뿐만 아니라, 반치사량의 X-선을 조사한 rat, guinea pig와 같은 실험동물에 있어서도 30일간의 생존율이 더 연장되므로서 현저한 효과를 보였다. 혈액상태 특히 혈소판의 양적 회복은 열에 안정한 이 분획에 의해서도 촉진되었다. 열에 안정한 분획을 투여한 mice에 있어서 X-선 조사에 의한 출혈이 방지되는데, 이를 매일 매일의 변에서 잠재혈액을 측정함으로써 정량적으로 관찰하였다. 결론적으로, 인삼 투여로 방사선에 의한 치사율이 감소되는데 이의 기전은 혈소판 생성을 촉진시키며, X-선에 의한 출혈을 감소시키기 때문이다.

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Formation of Cobalt Ferrit Epitaxial Iron Oxide and Their Magnetic Properties(I) (코발트 훼라이트 에피탁시얼 산화철의 생성과 자기특성(I))

  • 변태봉;김대영;이재영;손진군
    • Journal of the Korean Magnetics Society
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    • v.2 no.1
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    • pp.8-14
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    • 1992
  • To improve the coercivity of ${\gamma}-Fe_{2}O_{3}$ particles. We have made cobalt ferrite epitaxial ${\gamma}-Fe_{2}O_{3}$ particles by crystallizing cobalt ferrite on the surface of ${\gamma}-Fe_{2}O_{3}$ particles. The coercivity of $Co_{x}Fe_{3-x}O_{4}$ which is conform to coating layer showed the most superior characteristic when the value of x was 1. On the formation of cobalt epitaxial ${\gamma}-Fe_{2}O_{3}$ particles, controlling reaction atmosphere as oxidation at. mosphere after non-oxidation atmosphere was the optimum condition to prepare cobalt epitaxial ${\gamma}-Fe_{2}O_{3}$ particles with superior magnetic properties. Epitaxial growth of cobalt ferrite on the surface of ${\gamma}-Fe_{2}O_{3}$ particles was accomplished at $90^{\circ}C$ for 30 minutes.

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A study on the optical property and in-situ preparation of water-based acrylic emulsion containing $Cu_xS$ nanoparticle (금속 nanoparticle이 함유된 수분산성 아크릴 코팅제의 제조 및 흡광 특성)

  • Lee, Soo;Kim, Jin-Woo
    • Journal of the Korean Applied Science and Technology
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    • v.27 no.4
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    • pp.445-451
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    • 2010
  • To prepare very stable acrylic type emulsion having a visible ray absorption property, in-situ preparation technique of $Cu_xS$ nanoparticle was adopted. Firstly, the acylic emulsions of methyl methacrylate(MMA), butyl acrylate(BA), and acrylonitrile(AN) were synthesized by pre-emulsion polymerization at $60^{\circ}C$ in the presence of anionic surfactant. Secondly, $Cu_xS$ nanocomposited emulsions were directly prepared in the prepolymerized acrylic emulsion with $CuSO_4$ at $50^{\circ}C$. The presnce of $Cu_xS$ nanoparticle in emulsion was confirmed by SEM and EDS. The final $Cu_xS$ nanocomposited emulsion showed an olive-green colour and good emulsion stability up to 1 month. In addition the PET films coated with our $Cu_xS$ nanocomposited emulsion absorbed effectively the visible ray.

Oscillation of Second-Order Nonlinear Forced Functional Dynamic Equations with Damping Term on Time Scales

  • Agwa, Hassan Ahmed;Khodier, Ahmed Mahmoud;Ahmed, Heba Mostaafa Atteya
    • Kyungpook Mathematical Journal
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    • v.56 no.3
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    • pp.777-789
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    • 2016
  • In this paper, we establish some new oscillation criteria for the second-order forced nonlinear functional dynamic equations with damping term $$(r(t)x^{\Delta}(t))^{\Delta}+q({\sigma}(t))x^{\Delta}(t)+p(t)f(x({\tau}(t)))=e(t)$$, and $$(r(t)x^{\Delta}(t))^{\Delta}+q(t)x^{\Delta}(t)+p(t)f(x({\sigma}(t)))=e(t)$$, on a time scale ${\mathbb{T}}$, where r(t), p(t) and q(t) are real-valued right-dense continuous (rd-continuous) functions [1] defined on ${\mathbb{T}}$ with p(t) < 0 and ${\tau}:{\mathbb{T}}{\rightarrow}{\mathbb{T}}$ is a strictly increasing differentiable function and ${\lim}_{t{\rightarrow}{\infty}}{\tau}(t)={\infty}$. No restriction is imposed on the forcing term e(t) to satisfy Kartsatos condition. Our results generalize and extend some pervious results [5, 8, 10, 11, 12] and can be applied to some oscillation problems that not discussed before. Finally, we give some examples to illustrate our main results.

Method of Fare Payment based on Open API using Mobile Phone (이동전화를 이용한 개방형 인터페이스 기반의 요금 지불 서비스 제공 방법)

  • Lim, Sun-Hwan;Lee, Jae-Yong;Kim, Byung-Chul
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.45 no.8
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    • pp.82-90
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    • 2008
  • In this paper, functional architecture for fare payment is designed that enables IT developers to create charge-related applications using telecommunications network elements. To support a business model that enables operators to offer integrated billing, a payment and an account management API is crucial. Using this model, a fare payment service consisting of a payment service and an account management service was created. Each service is based on the architecture of parlay X web services. For the modeling of payment and of account management, the new operation of "split charging" is required in Parlay X payment web services, as is the new operation "notification".