• Title/Summary/Keyword: Complex numbers

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STRONG LAWS OF LARGE NUMBERS FOR WEIGHTED SUMS OF NEGATIVELY DEPENDENT RANDOM VARIABLES

  • Ko, Mi-Hwa;Han, Kwang-Hee;Kim, Tae-Sung
    • Journal of the Korean Mathematical Society
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    • v.43 no.6
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    • pp.1325-1338
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    • 2006
  • For double arrays of constants ${a_{ni},\;1{\leq}i{\leq}k_n,\;n{\geq}1}$ and sequences of negatively orthant dependent random variables ${X_n,\;n{\geq}1}$, the conditions for strong law of large number of ${\sum}^{k_n}_{i=1}a_{ni}X_i$ are given. Both cases $k_n{\uparrow}{\infty}\;and\;k_n={\infty}$ are treated.

ON THE INFINITE PRODUCTS DERIVED FROM THETA SERIES II

  • Kim, Dae-Yeoul;Koo, Ja-Kyung
    • Journal of the Korean Mathematical Society
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    • v.45 no.5
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    • pp.1379-1391
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    • 2008
  • Let k be an imaginary quadratic field, ${\eta}$ the complex upper half plane, and let ${\tau}{\in}{\eta}{\cap}k,\;q=e^{{\pi}{i}{\tau}}$. For n, t ${\in}{\mathbb{Z}}^+$ with $1{\leq}t{\leq}n-1$, set n=${\delta}{\cdot}2^{\iota}$(${\delta}$=2, 3, 5, 7, 9, 13, 15) with ${\iota}{\geq}0$ integer. Then we show that $q{\frac}{n}{12}-{\frac}{t}{2}+{\frac}{t^2}{2n}{\prod}_{m=1}^{\infty}(1-q^{nm-t})(1-q^{{nm}-(n-t)})$ are algebraic numbers.

INVOLUTIONS ON SURFACES OF GENERAL TYPE WITH pg = 0 I. THE COMPOSED CASE

  • Shin, YongJoo
    • Communications of the Korean Mathematical Society
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    • v.28 no.3
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    • pp.425-432
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    • 2013
  • Let S be a minimal surface of general type with $p_g(S)=q(S)=0$ having an involution ${\sigma}$ over the field of complex numbers. It is well known that if the bicanonical map ${\varphi}$ of S is composed with ${\sigma}$, then the minimal resolution W of the quotient $S/{\sigma}$ is rational or birational to an Enriques surface. In this paper we prove that the surface W of S with $K^2_S=5,6,7,8$ having an involution ${\sigma}$ with which the bicanonical map ${\varphi}$ of S is composed is rational. This result applies in part to surfaces S with $K^2_S=5$ for which ${\varphi}$ has degree 4 and is composed with an involution ${\sigma}$. Also we list the examples available in the literature for the given $K^2_S$ and the degree of ${\varphi}$.

A Numerical Analysis for the Performance Improvement of a Channel Heat Exchanger (채널형 열교환기의 성능향상에 관한 수치해석)

  • Jang, Byung-Hyun;Kim, Si-Peom;Lee, Kwon-Hee
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.11 no.2
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    • pp.159-164
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    • 2012
  • The shell & tube heat exchanger is used throughout various industries because of its inexpensive cost and handiness when it comes to maintenance. However, it has many design elements such as the location and the shape of inlet and outlet, the numbers of tubes and baffles, etc. Also, the flow within the shell and the heat transfer are complex. This paper is performed numerical analysis to evaluate capabilities of difference in temperature and pressure drop, which are the performance of channel heat exchanger, one of different types of shell & tube exchanger. Also, factors that affect the performance of channel heat exchanger were selected through design of experiment along with key factors.

Characterization of Functional Groups of Protonated Sargassum polycystum Biomass Capable of Binding Protons and Metal Ions

  • Yun, Yeoung-Sang
    • Journal of Microbiology and Biotechnology
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    • v.14 no.1
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    • pp.29-34
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    • 2004
  • Biosorption technology is recognized as an economically feasible alternative for the removal and/or recovery of metal ions from industrial wastewater sources. However, the structure of biosorbents is quite complex when compared with synthetic ion-exchange resins, which makes it difficult to quantify the ion-binding sites. Accordingly, this report describes a well-defined method to characterize the pK values and numbers of biomass functional groups from potentiometric titration data. When the proposed method was applied to Sargassum polycystum biomass as a model biosorbent, it was found that the biomass contained three types of functional groups. In addition, the carboxyl group (pK=$3.7{\pm}0.09$) was found to be the major binding sites ($2.57{\pm}0.06 mmol/g$) for positively-charged heavy-metal ions.

HAT Tidal Current Rotor Performance as per various Design Parameter (조류발전 로터 설계변수에 따른 성능 검토)

  • Jo, Chul-Hee;Yim, Jin-Young;Lee, Kang-Hee;Song, Seung-Ho
    • 한국신재생에너지학회:학술대회논문집
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    • 2009.11a
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    • pp.590-593
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    • 2009
  • Tidal current power system is one of ocean renewable energies that can minimize the environmental impact with many advantages compared to other energy sources. Not like others, the produced energy can be precisely predicted without weather conditions and also the operation rate is very high. To convert the current into power, the first device encountered to the incoming flow is the rotor that can transform into rotational energy. The performance of rotor can be determined by various design parameters including numbers of blade, sectional shape, diameter, and etc. The stream lines near the rotating rotor is very complex and the interference effects around the system is also difficult to predict. This paper introduces the experiment of rotor performance and also the effect of design parameter on the performance of HAT rotor by CFD.

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Babesia gibsoni Infection in Three Hunting Dogs (사냥개에서의 Babesia gibsoni 감염)

  • Shin Sang-Tae;Choi Hee-In;Sung Jai-Ki;Lee Chang-Woo
    • Journal of Veterinary Clinics
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    • v.4 no.2
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    • pp.505-514
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    • 1987
  • Babesia gibsoni infection was diagnosed and treated in three hunting dogs which were hospitalized to the Veterinary Teaching Hospital, College of Veterinary Medicine, Seoul National University between April 4 and August 29, 1987. All three dogs revealed severe anemia, hemoglobinuria, splenomegaly and markedly decreased PCV, RBC count and hemoglobin. The anemia was regenerative, as characterized by increased numbers of nucleated erythrocytes, polychromasia, anisocytosis, reticulocytosis. B. gibsoni was identified by examination of blood smear stained with Giemsa stain. The forms of B. gibsoni identified in this report were pleomorphic such as singnet ring, oval, comma, dot and elongated forms. The maximal percentages of erythrocytes infected with one or more B. gibsoni organisms were 39%, 20% and 40%, respectively. The Tick, Haemophysalis longicornis was assumed to be the vector of babesiosis in these cases. Specific treatment consisted of diminazene aceturate and supportive treatment consisted of whole blood transfusion, lactated Ringer's solution, vitamin B complex and broad spectrum antibiotics. All three dogs had convalesced successfully after treatment.

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Further Results about the Normal Family of Meromorphic Functions and Shared Sets

  • Qi, Jianming;Zhang, Guowei;Zhou, Linlin
    • Kyungpook Mathematical Journal
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    • v.52 no.1
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    • pp.39-47
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    • 2012
  • Let $\mathcal{F}$ be a family of meromorphic functions in a domain D, and let $k$, $n({\geq}2)$ be two positive integers, and let $S=\{a_1,a_2,{\ldots},a_n\}$, where $a_1$, $a_2$, ${\ldots}$, $a_n$ are distinct finite complex numbers. If for each $f{\in}\mathcal{F}$, all zeros of $f$ have multiplicity at least $k+1$, $f$ and $G(f)$ share the set $S$ in $D$, where $G(f)=P(f^{(k)})+H(f)$ is a differential polynomial of $f$, then$\mathcal{F}$ is normal in $D$.

Immunocytochemical Mapping of Serotonergic Neurons in Postembrvonic Brains of Cabbage Butterfly Pieris rcpce (배추흰나비 유충, 용, 성충의 뇌에 분포하는 세로토닌 면역반응성 신경원)

  • 이봉희;심재원
    • The Korean Journal of Zoology
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    • v.35 no.4
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    • pp.428-438
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    • 1992
  • The serotonin-immunoreactive (5-HTil neurons have been investigated in the brains of lanra, pupa and adult from Pieris ropae. There are ca. 54 5-HTi neurons in 5-instar larva, ca. 20 in 2-dav-old pupa and ca. 118 in 1-day-old adult, respectively. Most of these 5-HTi neurons are interneurons, but efferent and afferent 5-HTi neurons were also observed. Most of the 5-HTi neurons project into the central neuropils of postembrvonic brains. The larval brain contains abundant 5-HTi processes in the central neuropils, including those in three cerebral commissures. But in the pupal brain the 5-HTi processes are restricted in small numbers to the given regions of central neuropil. The adult brain contains a large number of 5-HTi processes in mushroom body, central body complex, lateral protocerebrum, protocerebral bridge, antennal lobe, and tritocerebral and suboesophageal neuropils. However, the 5-HTi processes are not found in the optic lobe of the brains. One prominent feature of the 5-HTi fibers in the postembrvonic brains is the fact that they are greatly arborized.

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On the Thought about How to Solve the Inequality (부등식의 풀이에 대한 연구)

  • Kim, Dong Hwa;Lee, Min Jung;Lee, Yang
    • East Asian mathematical journal
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    • v.30 no.4
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    • pp.571-581
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    • 2014
  • Students might find different solutions to the quadratic inequalities according to the range of the number representing the character of the inequalities. They have confusion when the roots of a quadratic inequality are complex numbers since the character of the inequalities generally represents the real number in the mathematics textbooks. Therefore we suggest that we must explain definitely the range of the number representing the character for each inequality question.