• 제목/요약/키워드: convergent series

검색결과 82건 처리시간 0.024초

통합 뉴스룸 도입 이후 뉴스생산 노동과정의 변화: CBS 통합뉴스룸 사례연구 (Changes in News-Production Labor Process Since The Introduction of Convergent Newsroom : A Case Study on The CBS Convergent Newsroom)

  • 윤익한;김균
    • 한국언론정보학보
    • /
    • 제55권
    • /
    • pp.164-183
    • /
    • 2011
  • 디지털 컨버전스의 기술 혁신은 언론 부문에서 핵심적인 노동이라고 할 수 있는 기자노동에도 막대한 영향을 주고 있다. 노동과정론에 따르면, 자본주의적 생산양식에서 기술혁신으로 인해 노동자들은 노동에 대한 통제력을 상실해가면서 탈숙련화의 과정을 겪어 왔고, 경영진들은 억압적인 노동조건을 은폐하고 노동자들을 더욱 효율적으로 통제하기 위해 이데올로기적, 정치적 장치들을 도입해 왔다. 이러한 문제의식 위에서 본 연구는 뉴스룸 통합의 기술혁신이 기자노동의 숙련도에 어떠한 영향을 주는지, 또 경영진들이 기자들을 통제하기 위해 사용하는 전략이 무엇인지를 CBS 통합뉴스룸의 사례를 통해 실증적으로 분석하였다. 분석 결과, 통합뉴스룸 도입으로 인해 기자들은 숙련노동에 대한 통제력을 상실해가면서 탈숙련화되고 있었다. 또한, 경영진들은 새로운 뉴스생산관행, 가족주의 노사문화에 대한 노동자들의 동의를 획득해 나갔으며, 내부노동시장 분절화를 통해 기업권력의 강화와 노동사회의 고립화 전략을 취하고 있었다.

  • PDF

주기적으로 slot가 있는 도파관 복사계의 전자계해석 (Field Analysis of Periodically Slotted Waveguide Structures Excited by an Aperiodic Source)

  • Kim, Young-Cho
    • 대한전자공학회논문지
    • /
    • 제23권2호
    • /
    • pp.131-148
    • /
    • 1986
  • A field ploblem of a grounded dielectric slab covered by a conducting plane with periodecally spaced arbitrary number of slots excited by an aperiodis source is analyzed. The problem is formulated in terms of simultaneous integral equations for unknown electric fields at each slot. A sampling technique is introduced to reduce the system equations to a matrix equation equation involving Green's function matrix. The solution obtained in the form of infinite series is transformed, into a more rapidly convergent one in its final stage. Theoretical results agree closesly with the experimental results.

  • PDF

A Theoretical Analysis of Thermic Endfire Interstitial Applicator

  • Park, Jong-Kweon;Eom, Hyo-Joon
    • Journal of electromagnetic engineering and science
    • /
    • 제1권1호
    • /
    • pp.60-62
    • /
    • 2001
  • A novel approach for modeling the thermic endfire interstitial applicator is presented. A hypothetical semi-infinite circular cylinder is added in the endfire direction in order to facilitate the theoretical modeling approach. The Fourier transform and mode-matching technique is utilized to obtain a solution in fast-convergent series Numerical computations for the input impedance are performed to check the Validity of the theoretical model.

  • PDF

CLASSES OF HIGHER ORDER CONVERGENT ITERATIVE METHODS FOR SOLVING NONLINEAR EQUATIONS

  • FAROOQ AHMED SHAH
    • Journal of Applied and Pure Mathematics
    • /
    • 제6권3_4호
    • /
    • pp.177-189
    • /
    • 2024
  • In this paper, we suggest and analyze new higher order classes of iterative methods for solving nonlinear equations by using variational iteration technique. We present several examples to illustrate the efficiency of the proposed methods. Comparison with other similar methods is also given. New methods can be considered as an alternative of the existing methods. This technique can be used to suggest a wide class of new iterative methods for solving nonlinear equations.

A Determination of an Optimal Clustering Method Based on Data Characteristics

  • Kim, Jeong-Hun;Yoo, Kwan-Hee;Nasridinov, Aziz
    • 예술인문사회 융합 멀티미디어 논문지
    • /
    • 제7권8호
    • /
    • pp.305-314
    • /
    • 2017
  • Clustering is a method that collects data objects into groups based on their similary. Performance of the state-of-the-art clustering methods is different according to the data characteristics. There have been numerous studies that performed experiments to compare the accuracy of the state-of-the-art clustering methods by applying various kinds of datasets. A common problem of these studies is that they only consider clustering algorithms that yield the most accurate results for a particular dataset. They do not consider what factors affect the execution time of each clustering method and how they are affected. Nevertheless, execution time is an important factor in clustering performance if there is no significant difference in accuracy. In order to solve the problems of the existing research, through a series of experiments using various types of datasets, we compare the accuracy of four representative clustering methods. In addition, we perform practical clustering performance comparisons by deriving time complexity and identifying factors that influences to its performance.

LEONHARD EULER (1707-1783) AND THE COMPUTATIONAL ASPECTS OF SOME ZETA-FUNCTION SERIES

  • Srivastava, Hari Mohan
    • 대한수학회지
    • /
    • 제44권5호
    • /
    • pp.1163-1184
    • /
    • 2007
  • In this presentation dedicated to the tricentennial birth anniversary of the great eighteenth-century Swiss mathematician, Leonhard Euler (1707-1783), we begin by remarking about the so-called Basler problem of evaluating the Zeta function ${\zeta}(s)$ [in the much later notation of Georg Friedrich Bernhard Riemann (1826-1866)] when s=2, which was then of vital importance to Euler and to many other contemporary mathematicians including especially the Bernoulli brothers [Jakob Bernoulli (1654-1705) and Johann Bernoulli (1667-1748)], and for which a fascinatingly large number of seemingly independent solutions have appeared in the mathematical literature ever since Euler first solved this problem in the year 1736. We then investigate various recent developments on the evaluations and representations of ${\zeta}(s)$ when $s{\in}{\mathbb{N}}{\backslash}\;[1],\;{\mathbb{N}}$ being the set of natural numbers. We emphasize upon several interesting classes of rapidly convergent series representations for ${\zeta}(2n+1)(n{\in}{\mathbb{N}})$ which have been developed in recent years. In two of many computationally useful special cases considered here, it is observed that ${\zeta}(3)$ can be represented by means of series which converge much more rapidly than that in Euler's celebrated formula as well as the series used recently by Roger $Ap\'{e}ry$ (1916-1994) in his proof of the irrationality of ${\zeta}(3)$. Symbolic and numerical computations using Mathematica (Version 4.0) for Linux show, among other things, that only 50 terms of one of these series are capable of producing an accuracy of seven decimal places.

겨울철 동해상의 대상수렴운과 그 주위의 대류운에 관한 WRF 수치모의 연구 (WRF Numerical Study on the Convergent Cloud Band and Its Neighbouring Convective Clouds)

  • 김유진;이재규
    • 대기
    • /
    • 제24권1호
    • /
    • pp.49-68
    • /
    • 2014
  • This study analyzed atmospheric conditions for the convergent cloud band (Cu-Cb line) in developing stage and its neighbouring convections formed over the East Sea on 1 February 2012, by using synoptic, satellites data, and WRF numerical simulation output of high resolution. In both satellite images and the WRF numerical simulation outputs, the Cu-Cb line that stretched out toward northwest-southeast was shown in the East Sea, and cloud lines of the L mode were aligned in accordance with the prevailing surface wind direction. However, those of the T mode were aligned in the direction of NE-SW, which was nearly perpendicular direction to the surface winds. The directions of the wind shear vectors connecting top winds and bottom winds of the moist layers of the L mode and the T mode were identical with those of the cloud lines of L mode and T mode, respectively. From the WRF simulation convection circulations with a convergence in the lower layer of atmosphere and a divergence above 1.5 km ASL (Above Sea Level) were identified in the Cu-Cb line. A series of small sized vortexes (maximum vortex: $320{\times}10^{-5}s^{-1}$) of meso-${\gamma}$-scale formed by convergences was found along the Cu-Cb lines, suggesting that Cu-Cb lines, consisting of numerous convective clouds, were closely associated with a series of the small vortexes. There was an absolute unstable layer (${\partial}{\theta}/{\partial}z$ < 0) between sfc and ~0.3 km ASL, and a stable layer (${\partial}{\theta}/{\partial}z$ > 0) above ~2 km ASL over the Cu-Cb line and cloud zones. Not only convectively unstable layers (${\partial}{\theta}_e/{\partial}z$ < 0) but also neutral layers (${\partial}{\theta}_e/{\partial}z{\approx}=0$) in the lower atmosphere (sfc~1.5 km ASL) were scattered around over the cloud zones. Particularly, for the Cu-Cb line there were convectively unstable layers in the surface layer, and neutral layers (${\partial}{\theta}_e/{\partial}z{\approx}=0$) between 0.2 and ~1.5 km ASL over near the center of the Cu-Cb line, and the neutralization of unstable layers came from the release of convective instability.

Numerical Solutions of Third-Order Boundary Value Problems associated with Draining and Coating Flows

  • Ahmed, Jishan
    • Kyungpook Mathematical Journal
    • /
    • 제57권4호
    • /
    • pp.651-665
    • /
    • 2017
  • Some computational fluid dynamics problems concerning the thin films flow of viscous fluid with a free surface and draining or coating fluid-flow problems can be delineated by third-order ordinary differential equations. In this paper, the aim is to introduce the numerical solutions of the boundary value problems of such equations by variational iteration method. In this paper, it is shown that the third-order boundary value problems can be written as a system of integral equations, which can be solved by using the variational iteration method. These solutions are gleaned in terms of convergent series. Numerical examples are given to depict the method and their convergence.

등온 으로 가열되는 수평 평판위 를 지나는 블라시우스 유동 의 와류불안정성 해석 (An Analysis on Vortex Instability of Blasius Flow Over Isothermally Heated Horizontal Plates)

  • 이형인;최창균;유정열
    • 대한기계학회논문집
    • /
    • 제6권4호
    • /
    • pp.390-396
    • /
    • 1982
  • The onset of longitudinal vortices in horizontal Blasius flow isothermally heated from below is studied analytically. The assumption that at the onset of thermal instability the thermal disturbances are confined within the thermal boundary layer is employed for the limiting case of large Prandtl number. Polynomial representations for the basic quantities obtained by the integral method of the boundary layer analysis have been used. Then the system of differential equations and boundary conditions for disturbance quantities is reformulated in a convenient form so that the solutions may be constructed as rapidly convergent power series. The critical buoyancy parameter G $r_{x}$ $^{*}$ /R $e^{*1.5}$ falls between 2 and 6, which is about one order of magnitude lower than the existing experimental values. It is also shown that the positions of the onset of instability can be closely predicted by the present theory.y.y.

ASYMPTOTIC BEHAVIOR OF THE INVERSE OF TAILS OF HURWITZ ZETA FUNCTION

  • Lee, Ho-Hyeong;Park, Jong-Do
    • 대한수학회지
    • /
    • 제57권6호
    • /
    • pp.1535-1549
    • /
    • 2020
  • This paper deals with the inverse of tails of Hurwitz zeta function. More precisely, for any positive integer s ≥ 2 and 0 ≤ a < 1, we give an algorithm for finding a simple form of fs,a(n) such that $$\lim_{n{\rightarrow}{\infty}}\{\({\sum\limits_{k=n}^{\infty}}{\frac{1}{(k+a)^s}}\)^{-1}-f_{s,a}(n)\}=0$$. We show that fs,a(n) is a polynomial in n-a of order s-1. All coefficients of fs,a(n) are represented in terms of Bernoulli numbers.