• Title/Summary/Keyword: (${\epsilon},\

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Cold-Seep Sediment Harbors Phylogenetically Diverse Uncultured Bacteria

  • Cho, Jae-Chang;Lee, Sang-Hoon;Oh, Hae-Ryun;Lee, Jung-Hyun;Kim, Sang-Jin
    • Journal of Microbiology and Biotechnology
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    • v.14 no.5
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    • pp.906-913
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    • 2004
  • A culture-independent molecular phylogenetic survey was carried out on the bacterial community in cold-seep sediment at Edison Seamount, south of Lihir Island, Papua New Guinea. Small-subunit rRNA genes were amplified directly from the sediment DNA by PCR and cloned. The majority of the cloned 16S rRNA gene sequences were most closely related to as-yet-uncultivated microorganisms found in deep-sea sediments, and were primarily affiliated with one of four groups: the $\gamma$-, $\delta$-, and $\epsilon$-subdivisions of Proteobacteria, and Cytophaga-Flavobacterium-Bacteroides. We did not recover any sequences related to cyanobacteria, prochlorophytes, and $\alpha$-Proteobacteria, which are known to occur in great abundance within the surface mixed layer of the Atlantic and Pacific Oceans. The majority of the cloned $\gamma$-and $\epsilon$-Proteobacterial sequences were closely related to chemoautotrophic sulfur-oxidizing symbionts of marine benthic fauna, and the $\delta$-Proteobacterial sequences to sulfate- and sulfur-reducing bacteria, indicating that they might play an important role in chemoautotrophic primary production and the sulfur cycle in the cold-seep area. There results demonstrate the high diversity of the bacterial community in the cold-seep sediment, and substantially expand knowledge of the extent of bacterial diversity in this formidable and unique habitat.

A CHARACTERIZATION OF WEIGHTED BERGMAN-PRIVALOV SPACES ON THE UNIT BALL OF Cn

  • Matsugu, Yasuo;Miyazawa, Jun;Ueki, Sei-Ichiro
    • Journal of the Korean Mathematical Society
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    • v.39 no.5
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    • pp.783-800
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    • 2002
  • Let B denote the unit ball in $C^n$, and ν the normalized Lebesgue measure on B. For $\alpha$ > -1, define $dv_\alpha$(z) = $c_\alpha$$(1-\midz\mid^2)^{\alpha}$dν(z), z $\in$ B. Here $c_\alpha$ is a positive constant such that $v_\alpha$(B) = 1. Let H(B) denote the space of all holomorphic functions in B. For $p\geq1$, define the Bergman-Privalov space $(AN)^{p}(v_\alpha)$ by $(AN)^{p}(v_\alpha)$ = ${f\inH(B)$ : $\int_B{log(1+\midf\mid)}^pdv_\alpha\;<\;\infty}$ In this paper we prove that a function $f\inH(B)$ is in $(AN)^{p}$$(v_\alpha)$ if and only if $(1+\midf\mid)^{-2}{log(1+\midf\mid)}^{p-2}\mid\nablaf\mid^2\;\epsilon\;L^1(v_\alpha)$ in the case 1<p<$\infty$, or $(1+\midf\mid)^{-2}\midf\mid^{-1}\mid{\nabla}f\mid^2\;\epsilon\;L^1(v_\alpha)$ in the case p = 1, where $nabla$f is the gradient of f with respect to the Bergman metric on B. This is an analogous result to the characterization of the Hardy spaces by M. Stoll [18] and that of the Bergman spaces by C. Ouyang-W. Yang-R. Zhao [13].

Solution of TE Scattering by a Perfectly Conducting Strip Grating Over the Grounded Two Dielectric Layers Applying Fourier-Galerkin Moment Method (Fourier-Galerkin Moment Method를 이용한 접지된 2개 유전체층 위의 완전도체띠 격자구조에 의한 TE 산란의 해)

  • Yoon, Uei-Joong
    • Journal of Advanced Navigation Technology
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    • v.16 no.4
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    • pp.635-640
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    • 2012
  • In this paper, The TE (Transverse Electric) scattering problems by a perfectly conducting strip grating over a grounded two dielectric layers are analyzed by applying the conductive boundary condition and the FGMM (Fourier-Galerkin Moment Method) known as a numerical procedure, then the induced surface current density is expanded in a series of the multiplication of the unknown coefficient and the exponential function as a simple function. Generally, the reflected power gets increased according as the relative permittivity ${\epsilon}_{r2}$ and the thickness of dielectric layer $t_2$ of the region-2 in the presented structure gets increased, respectively. The sharp variations of the reflected power are due to resonance effects were previously called wood's anomaly, the numerical results show in good agreement with those of the existing papers.

Electromagnetic Vector Fields Simulation with Mathematica (전자기 벡터장 시각화를 위한 Mathematica 시뮬레이션)

  • Choi, Yong-Dae;Yun, Hee-Joong
    • Journal of the Korean Vacuum Society
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    • v.21 no.2
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    • pp.69-77
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    • 2012
  • Visualization of the electromagnetic vector fields are presented and examined with Mathematica. Vector fields may be used to represent a great of many physical quantities in various area of physics, including electromagnetism with vector differential operators. Because they deal with abstract, three-dimensional fields that are some times very difficult to visualize, electromagnetism can be conceptually rather difficult. Visual representation of such an abstract vector fields is invaluable to student or researchers working in this field and also helps teaching electromagnetism to physics or engineering students. Mathematica provides a wider range of graphical tools including plot of vector fields and vector analysis, which can be applied to visualization of electromagnetic system. We have visualized the most fundamental concepts of the electromagnetic vector $\vec{E}=-\vec{\nabla}_{\varphi}$, $\vec{D}={\epsilon}\vec{E}$, $\vec{\nabla}{\times}\vec{A}$, $\vec{B}={\mu}\vec{H}$, $\vec{B}={\mu}_0(\vec{H}+\vec{M})$, which are confirmed with vector calculations and valid graphically with some presentations.

Phospholipase C Epsilon 1 (PLCE1 rs2274223A>G, rs3765524C>T and rs7922612C>T) Polymorphisms and Esophageal Cancer Risk in the Kashmir Valley

  • Malik, Manzoor Ahmad;Umar, Meenakshi;Gupta, Usha;Zargar, Showkat Ali;Mittal, Balraj
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.10
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    • pp.4319-4323
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    • 2014
  • Background: Phospholipase C epsilon 1 (PLCE1) encodes a member of the phospholipase family of proteins that play crucial roles in carcinogenesis and progression of several cancers including esophageal cancer (EC). In two large scale genome-wide association studies (GWAS) single nucleotide polymorphisms (SNP, rs2274223A>G, rs3765524C>T) in PLCE1 were identified as novel susceptibility loci of esophageal cancer (EC) in China. The aim of the present study was to investigate this finding in Kashmir Valley, a high risk area. Materials and Methods: We determined genotypes of three potentially functional SNPs (rs2274223A>G, rs3765524C>T and rs7922612C>T) of PLCE1 in 135 EC patients, and 195 age and gender matched controls in Kashmiri valley by PCR RFLP method. Risk for developing EC was estimated by binary logistic regression using SPSS. Results: The selected PLCE1 polymorphisms did not show independent association with EC. However, the $G_{2274223}T_{3765524}T_{7922612}$ haplotype was significantly associated with increased risk of EC (OR=2.92; 95% CI=1.30-6.54; p=0.009). Smoking and salted tea proved to be independent risk factors for EC. Conclusions: Genetic variations in PLCE1 modulate risk of EC in the high risk Kashmiri population.

A Study of Wind Pressure Distribution for a Rectangular Building Using CFD (CFD를 이용한 박스형 건물의 풍압분포 분석에 관한 연구)

  • Shin, Dongshin;Park, Jaehyun;Kang, Bomi;Kim, Eunmi;Lim, Hyeongjun;Lee, Jinyoung
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.28 no.1
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    • pp.1-6
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    • 2016
  • This paper studies the wind pressure distribution over the Commonwealth Advisory Aeronautical Council building model (CAARC model) using CFD. We also considered the interaction between the CAARC model and other buildings. The Reynolds number based on the building height was 380,000. The number of sells for the simulation was about 500,000. The wind pressure was lowest when the wind direction was blowing at an angle 45 degrees of the CAARC model. When the gap between the two buildings in front of the CAARC was over 1/2 the horizontal length of the CAARC model, the wind pressure was higher than the pressure without the two buildings. When the distance between the two front buildings and the CAARC was less than 1.5 times the vertical length of the CAARC model, the wind pressure increased. Accordingly, the relative distance between two buildings or the distance from the CAARC model should be considered when extra wind exists due to other buildings.

Microwave Dielectric Properties of $0.7Ca(Li_{1/4}Nb_{3/4})O_3-0.3CaTiO_3$ Ceramics Added with zinc-borosilicate Glass Frit (Zinc-borosilicate Glass Frit 첨가에 따른 $0.7Ca(Li_{1/4}Nb_{3/4})O_3-0.3CaTiO_3$ 세라믹스의 마이크로파 유전 특성)

  • Yoon, Sang-Ok;Kim, Kwan-Soo;Jo, Tae-Hyun;Oh, Chang-Yong;Kim, Chan-Hang;Shim, Sang-Heung
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.11a
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    • pp.371-374
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    • 2004
  • 저온동시 소성용(low temperature co-fired ceramics, LTCC) 마이크로파 유전체을 만들기 위해 $Ca(Li_{1/4}Nb_{3/4})O_3$ 마이크로파 유전체 세라믹스에 zinc-borosililcate glass를 첨가하여 소결 특성과 마이크로파 유전 특성을 조사하였다. $Ca(Li_{1/4}Nb_{3/4})O_3$$0.7Ca(Li_{1/4}Nb_{3/4})O_3-0.3CaTiO_3$에 zinc-borosilicate를 $5{\sim}30wt%$ 첨가하여 소결한 결과 $875{\sim}925^{\circ}C$에서 동시 소성이 가능한 것으로 확인되었으며 zinc-borosilicate glass의 함량이 증가할수록 저온에서 소성이 가능하였지만 과량의 액상과 2차상이 형성되면서 유전율과 품질계수가 저하되는 경향을 나타내었다. $Ca(Li_{1/4}Nb_{3/4})O_3$에 5wt%의 zinc-borosilicate를 첨가하여 $900^{\circ}C$에서 소성한 결과 가장 우수한 유전 특성$(\epsilon_r=17.45,\;Q{\times}f_0=5487)$을 나타내었고, 유전율을 높이기 위해 $CaTiO_3$를 0.3mol% 첨가한 $0.7Ca(Li_{1/4}Nb_{3/4})O_3-0.3CaTiO_3$에 10wt%의 zinc-borosilicate를 첨가하여 $925^{\circ}C$에서 소성한 결과 가장 우수한 유전특성$(\epsilon_r=44.92,\;Q{\times}f_0=5567)$을 나타내었다.

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The UCT algorithm applied to find the best first move in the game of Tic-Tac-Toe (삼목 게임에서 최상의 첫 수를 구하기 위해 적용된 신뢰상한트리 알고리즘)

  • Lee, Byung-Doo;Park, Dong-Soo;Choi, Young-Wook
    • Journal of Korea Game Society
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    • v.15 no.5
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    • pp.109-118
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    • 2015
  • The game of Go originated from ancient China is regarded as one of the most difficult challenges in the filed of AI. Over the past few years, the top computer Go programs based on MCTS have surprisingly beaten professional players with handicap. MCTS is an approach that simulates a random sequence of legal moves until the game is ended, and replaced the traditional knowledge-based approach. We applied the UCT algorithm which is a MCTS variant to the game of Tic-Tac-Toe for finding the best first move, and compared it with the result generated by a pure MCTS. Furthermore, we introduced and compared the performances of epsilon-Greedy algorithm and UCB algorithm for solving the Multi-Armed Bandit problem to understand the UCB.

A Study of Parametric Effects on the Thermal Performance of Flat-Plate Liquid-Heating Solar Collectors (평판형 액체식 집열기 의 각종 변수 가 집열기 의 열성능 에 미치는 영향)

  • 전문헌;윤석범;추교명
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.8 no.2
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    • pp.145-153
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    • 1984
  • In the present work, a computer simulation is performed employing Hottel-Whillier-Bliss model for thermal performance of solar collectors. The major collector parameters examined in the computer simulation are: number of transparent glass covers(N), thermal emissivity of the absorbing plate surface (.epsilon.$_{P}$), absorptivity of absorber plate (.alpha.$_{p}$), flow rate per unit area of collector (G), $L_{b}$ / $k_{b}$ of insulation material, tilt angle of collector (S), and solar insolation(I). By varying numerical values of the major collector parameters around their typical values, the corresponding variations in thermal efficiency curves are examined. In addition, an experimental investigation has been carried out with a slightly modified KAIST collector test loop under a real sun condition in order to compare with the simulation results, examine the applicability of the mathematical model of the collector thermal performance, and study the effect of variation of flow rate (G) on thermal efficiency and the range of optimum flow rate.e.

Combined raidation-forced convection in a circular tube flow (원관내 유동에서의 복사 및 강제대류 열전달에 관한 연구)

  • 임승욱;이준식;이택식
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.14 no.6
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    • pp.1652-1660
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    • 1990
  • Combined radiative-convective heat transfer in a hot gas tube flow has been investigated numerically and experimentally. In the numerical analysis, a standard k-.epsilon. model is used for the evaluation of turbulent shear stresses and spherical harmonics method with the Weighted Sum of Gray Gases Model for the solution of radiative transfer equation. In the experimental study measured are the velocity and temperature of the hot gas flow generated by the propane gas combustion, and tude wall heat flux distribution. Numerical results are compared with experimental ones and it is confirmed that P-3 provides quite reliable results in the analysis of the combined radiation-convection system.