• 제목/요약/키워드: Near

검색결과 22,438건 처리시간 0.039초

근거리 무선 통신을 위한 소형 선형 안테나의 실현 가능성 연구 (Feasibility study of a small linear antenna for near range wireless communications)

  • 한대현;심재륜;최영식
    • 대한전자공학회:학술대회논문집
    • /
    • 대한전자공학회 2000년도 하계종합학술대회 논문집(1)
    • /
    • pp.267-270
    • /
    • 2000
  • The feasibility of small linear antenna for near range wireless communications was studied. The requirement of the system are frequency range 9∼12 MHz and antenna size 15 cm. The communication range is about 15 m. The antenna input impedance is very small radiation resistance and very large capacitive reactance. The lossless impedance matching is nearly impossible, therefore lossy matching is considered. The antenna has very low radiation efficiency. The near field calculation has a large uncertainty, but the results can be used as the guideline of a small linear antenna system for a near range wireless communication.

  • PDF

WEAKLY B-REGULAR NEAR-RINGS

  • Chelvam Thirugnanam Tamizh;Cho Yong-Uk
    • 한국수학교육학회지시리즈B:순수및응용수학
    • /
    • 제13권2호
    • /
    • pp.157-165
    • /
    • 2006
  • The notion of regularity in near-ring was generalized by the concept of b-regular and some characterizations of the same was obtained through the substructures viz bi-ideals in near-rings. In this paper, we generalize further and introduce tile notion of weakly b-regular near-rings and obtain a characterization of tile same.

  • PDF

SEMIPRIME NEAR-RINGS WITH ORTHOGONAL DERIVATIONS

  • Park, Kyoo-Hong;Jung, Yong-Soo
    • 한국수학교육학회지시리즈B:순수및응용수학
    • /
    • 제13권4호
    • /
    • pp.303-310
    • /
    • 2006
  • M. $Bre\v{s}ar$ and J. Vukman obtained some results concerning orthogonal derivations in semiprime rings which are related to the result that is well-known to a theorem of Posner for the product of two derivations in prime rings. In this paper, we present orthogonal generalized derivations in semiprime near-rings.

  • PDF

3 차원 놋치 및 쐐기의 응력 강도계수 (The intensity of a singular near-tip field around the vertex of a three-dimensional notch or wedge)

  • 이용우;임세영
    • 대한기계학회:학술대회논문집
    • /
    • 대한기계학회 2003년도 춘계학술대회
    • /
    • pp.157-162
    • /
    • 2003
  • Singular stress fields around three-dimensional wedges are examined, and the near-tip intensity is calculated via the two-state M-integral with the aid of the domain integral representation. A numerical example demonstrates the effectiveness and accuracy of the present scheme for computing the stress intensities of singular stresses near the generic three-dimensional wedges.

  • PDF

ORDER RESTRICTED TESTS FOR SYMMETRY AGAINST POSITIVE BIASEDNESS

  • Oh, Myong-Sik
    • Journal of the Korean Statistical Society
    • /
    • 제36권3호
    • /
    • pp.335-347
    • /
    • 2007
  • Two new types of positive biasedness, which are closely related to Type III positive biasedness (Yanagimoto and Sibuya, 1972), are proposed. We call these near Type III positive biasedness. Though no implication between Type II and near Type III biasedness exists, near Type III seems to be less restrictive than Type II biasedness. Constrained maximum likelihood estimates of distribution functions under near Type III positive bisedness are obtained. The likelihood ratio tests of symmetry against new positive biasedness restrictions are proposed. A small simulation study is conducted to compare the performance of the tests.

On fuzzy ideals of near-rings

  • Kim, Seung-Dong;Kim, Hee-Sik
    • 대한수학회보
    • /
    • 제33권4호
    • /
    • pp.593-601
    • /
    • 1996
  • W. Liu [11] has studied fuzzy ideals of a ring, and many researchers [5,6,7,16] are engaged in extending the concepts. The notion of fuzzy ideals and its properties were applied to various areas: semigroups [8,9,10,13,15], distributive lattices [2], artinian rings [12], BCK-algebras [14], near-rings [1]. In this paper we obtained an exact analogue of fuzzy ideals for near-ring which was discussed in [5, 11].

  • PDF

ON SEMIDERIVATIONS IN 3-PRIME NEAR-RINGS

  • Ashraf, Mohammad;Boua, Abdelkarim
    • 대한수학회논문집
    • /
    • 제31권3호
    • /
    • pp.433-445
    • /
    • 2016
  • In the present paper, we expand the domain of work on the concept of semiderivations in 3-prime near-rings through the study of structure and commutativity of near-rings admitting semiderivations satisfying certain differential identities. Moreover, several examples have been provided at places which show that the assumptions in the hypotheses of various theorems are not altogether superfluous.

근접장 기록을 위한 디스크의 광학적 특성 (Optical characteristics of discs for near-filed recording)

  • 민철기;박노철;박경수;박영필
    • 정보저장시스템학회논문집
    • /
    • 제5권2호
    • /
    • pp.64-69
    • /
    • 2009
  • In this paper, we investigate field distribution and interference pattern in the exit pupil and in the focal region. Also, we compare with metal and dielectric substrate for near-field recording. To obtain field distribution, we use modified vector diffraction theory and Zernike Polynomials. Finally, we design and optimize refractive index and thickness of disk for near-field surface recording and cover-layer incident recording.

  • PDF

DEGREE OF NEARNESS

  • Lee, Seung On;Lee, Eun Pyo
    • 충청수학회지
    • /
    • 제21권2호
    • /
    • pp.175-182
    • /
    • 2008
  • This paper is a revised version of [5]. In [5], we define' nearness between two points' in a topological space in many ways and show that a continuous function preserves one-sided nearness. We also show that a $T_1$-space is characterized by one-sided nearness exactly. In this paper, we introduce extremally disconnected spaces and show that the new topology generated by the set of equivalence classes as a base is extremally disconnected.

  • PDF