• 제목/요약/키워드: R-507

검색결과 167건 처리시간 0.027초

COMPLEX DELAY-DIFFERENTIAL EQUATIONS OF MALMQUIST TYPE

  • NAGASWARA, P.;RAJESHWARI, S.
    • Journal of applied mathematics & informatics
    • /
    • 제40권3_4호
    • /
    • pp.507-513
    • /
    • 2022
  • In this paper, we investigate some results on complex delay-differential equations of the classical Malmquist theorem. A classic illustrations of their results states us that if a complex delay equation w(t + 1) + w(t - 1) = R(t, w) with R(t, w) rational in both arguments admits (concede) a transcendental meromorphic solution of finite order, then degwR(t, w) ≤ 2. Development and upgrade of such results are presented in this paper. In addition, Borel exceptional zeros and poles seem to appear in special situations.

R-502의 대체냉매를 사용한 냉동시스템의 성능 및 열전달 특성 (Performance and heat transfer characteristics of refrigeration system using R-502 alternatives)

  • 박창대;김민수;노승탁
    • 설비공학논문집
    • /
    • 제11권5호
    • /
    • pp.624-632
    • /
    • 1999
  • In order to replace CFC-502 which has been widely used in transportation and low temperature refrigeration system, performance tests using HFC-407A, HFC-404A and HFC-507 have been carried out. Measurements were conducted at two different condensing temperatures of $43.3^{\circ}C$and $54.5^{\circ}C$ for each refrigerant. System performance characteristics and heat transfer characteristics of each refrigerant were obtained at several compressor speeds and evaporating temperatures ranging from$-25^{\circ}C$ to $-10^{\circ}C$ Test results show that the use of tested alternative refrigerants without changing system components offers the potential performance improvement of a refrigeration system.

  • PDF

NILRADICALS OF SKEW POWER SERIES RINGS

  • Hong, Chan-Yong;Kim, Nam-Kyun;Kwak, Tai-Keun
    • 대한수학회보
    • /
    • 제41권3호
    • /
    • pp.507-519
    • /
    • 2004
  • For a ring endomorphism $\sigma$ of a ring R, J. Krempa called $\sigma$ a rigid endomorphism if a$\sigma$(a)=0 implies a=0 for a ${\in}$R. A ring R is called rigid if there exists a rigid endomorphism of R. In this paper, we extend the (J'-rigid property of a ring R to the upper nilradical $N_{r}$(R) of R. For an endomorphism R and the upper nilradical $N_{r}$(R) of a ring R, we introduce the condition (*): $N_{r}$(R) is a $\sigma$-ideal of R and a$\sigma$(a) ${\in}$ $N_{r}$(R) implies a ${\in}$ $N_{r}$(R) for a ${\in}$ R. We study characterizations of a ring R with an endomorphism $\sigma$ satisfying the condition (*), and we investigate their related properties. The connections between the upper nilradical of R and the upper nilradical of the skew power series ring R[[$\chi$;$\sigma$]] of R are also investigated.ated.

16비트 깊이 이상의 이미지에서의 중간값 필터 계산 (Computing Median Filter for over 16-bit Depth Images)

  • 김진욱
    • 전기전자학회논문지
    • /
    • 제24권2호
    • /
    • pp.507-513
    • /
    • 2020
  • 중간값 필터는 n×m 크기의 이미지와 반경 r이 주어지면 이미지의 모든 픽셀에 대해 반경 r에 속하는 픽셀들의 중간값으로 변환하는 것으로, 이미지 처리가 필요한 다양한 분야에서 활용되고 있다. 픽셀의 정보가 8비트인 경우에는 O(nm) 시간 알고리즘이 존재하나 16비트 이상에는 적용이 어렵고 대신 Gil과 Werman의 O(nmlog2r) 시간 알고리즘이 존재한다. 본 논문에서는 16비트 깊이 이상의 정보를 갖는 이미지에 대해서도 효율적으로 동작하는 중간값 필터 알고리즘을 제안한다. 시간 복잡도는 O(nmlog2r)로 Gil과 Werman의 알고리즘과 동일하지만 엄밀한 분석과 실험을 통해 2배 이상 향상됨을 보인다.

Certain Geometric Properties of an Integral Operator Involving Bessel Functions

  • Selvakumaran, Kuppathai Appasamy;Szasz, Robert
    • Kyungpook Mathematical Journal
    • /
    • 제58권3호
    • /
    • pp.507-517
    • /
    • 2018
  • In this article, we introduce a new integral operator involving normalized Bessel functions of the first kind and we obtain a set of sufficient conditions for univalence. Our results contain some interesting corollaries as special cases. Further, as particular cases, we improve some of the univalence conditions proved in [2].

On f-cosymplectic and (k, µ)-cosymplectic Manifolds Admitting Fischer -Marsden Conjecture

  • Sangeetha Mahadevappa;Halammanavar Gangadharappa Nagaraja
    • Kyungpook Mathematical Journal
    • /
    • 제63권3호
    • /
    • pp.507-519
    • /
    • 2023
  • The aim of this paper is to study the Fisher-Marsden conjucture in the frame work of f-cosymplectic and (k, µ)-cosymplectic manifolds. First we prove that a compact f-cosymplectic manifold satisfying the Fisher-Marsden equation R'*g = 0 is either Einstein manifold or locally product of Kahler manifold and an interval or unit circle S1. Further we obtain that in almost (k, µ)-cosymplectic manifold with k < 0, the Fisher-Marsden equation has a trivial solution.

참깨의 볶음조건이 참깨박 정유성분의 휘발성 성분 패턴에 미치는 영향 (The Effects of Sesame Seed Roasting Conditions on Volatile Component Patterns of Essential Oils Obtained from Sesame Meals)

  • 이장우;윤여철;전남규;김선호;박상순
    • 한국식품영양학회지
    • /
    • 제20권1호
    • /
    • pp.9-13
    • /
    • 2007
  • 참깨로부터 참기름을 채유하고 부산물로 얻어진 참깨박을 이용하여 천연 향료의 원료를 얻기 위하여 참깨의 전처리 조건을 달리하여 각각 2종의 참기름과 참깨박을 얻었다. 참깨의 볶음온도를 200$^{\circ}C$, 220$^{\circ}C$로 차등화하여 얻어진 참기름 A, B는 각각 1,397.1 ppm, 1,518.8 ppm이었고, 참깨박 A, B는 각각 663.2 ppm, 775.3 ppm 및 참기름향은 16,507.9 ppm으로 차이를 보였다. 2종의 참기름에서 공통적으로 주요 휘발성 성분은 pentane, 2-butanone, pyrazine, methyl pyrazine, 2,5- 및 2,6-dimethyl pyrazine, furfuryl alcohol, guaiacol, 4-vinylguaiacol 이었다. 총 26종의 성분 중 pyrazine류는 각각 834.4 ppm, 816.4 ppm으로 전체의 59.72%, 53.75%를 차지하여 이 성분이 참기름의 향기를 결정해 주는 가장 큰 영향인자로 판단된다. 2종의 참깨박 A, B시료에서 주요 휘발성 성분은 2-butanone, hexanal, pyrazine, methyl pyrazine, 2,6-dimethyl pyrazine, furfuryl alcohol로 참기름과는 차이를 보였다. 상대적으로 참기름 향료에서는 총 16,507.9 ppm의 휘발성 성분이 검출되었고, 주요 성분은 2-butanone, guaiacol, 4-vinylguaiacol이 각각 1,000 ppm 이상으로 전체의 35.02%를 차지하였다.

R-트리를 이용한 직선상의 공간 객체 검색 (Searching Spatial Objects on a Straight Line using R-tree)

  • 김유진;편동현;표창우
    • 한국정보과학회:학술대회논문집
    • /
    • 한국정보과학회 2010년도 한국컴퓨터종합학술대회논문집 Vol.37 No.1(B)
    • /
    • pp.503-507
    • /
    • 2010
  • 두 지점 사이의 직선경로 위에 위치하는 공간 객체를 검색하기 위한 효율적인 알고리즘을 제안하였다. 이 알고리즘은 공간 객체의 인덱스 구조로 R-트리를 사용하였고, 한정 직사각형 (bounding rectangle)의 대각선 정보를 사용하여 검색하는 방식이다. R-트리를 구성할 때 각 노드에 대응하는 한정 직사각형의 2개의 대각선 정보를 추가해 놓으면 검색의 정확성을 높여 시간을 줄일 수 있다. 공간 객체의 밀집도가 높은 경우 10% ~ 30% 검색 시간 감축 효과를 볼 수 있다.

  • PDF

Complete Moment Convergence of Moving Average Processes Generated by Negatively Associated Sequences

  • Ko, Mi-Hwa
    • Communications for Statistical Applications and Methods
    • /
    • 제17권4호
    • /
    • pp.507-513
    • /
    • 2010
  • Let {$X_i,-{\infty}$ < 1 < $\infty$} be a doubly infinite sequence of identically distributed and negatively associated random variables with mean zero and finite variance and {$a_i,\;-{\infty}$ < i < ${\infty}$} be an absolutely summable sequence of real numbers. Define a moving average process as $Y_n={\sum}_{i=-\infty}^{\infty}a_{i+n}X_i$, n $\geq$ 1 and $S_n=Y_1+{\cdots}+Y_n$. In this paper we prove that E|$X_1$|$^rh$($|X_1|^p$) < $\infty$ implies ${\sum}_{n=1}^{\infty}n^{r/p-2-q/p}h(n)E{max_{1{\leq}k{\leq}n}|S_k|-{\epsilon}n^{1/p}}{_+^q}<{\infty}$ and ${\sum}_{n=1}^{\infty}n^{r/p-2}h(n)E{sup_{k{\leq}n}|k^{-1/p}S_k|-{\epsilon}}{_+^q}<{\infty}$ for all ${\epsilon}$ > 0 and all q > 0, where h(x) > 0 (x > 0) is a slowly varying function, 1 ${\leq}$ p < 2 and r > 1 + p/2.

Genetic Analysis of a Structural Motif Within the Conserved 530 Stem-Loop of Escherichia coli 16S rRNA

  • Szatkiewicz Jin P.;Cho Hyun-Dae;Ryou Sang-Mi;Kim Jong-Myung;Cunningham Philip R.;Lee Kang-Seok
    • Journal of Microbiology and Biotechnology
    • /
    • 제16권4호
    • /
    • pp.569-575
    • /
    • 2006
  • The 530 stem-loop is a 46 nucleotide stem-loop structure found in all small-subunit ribosomal RNAs. Phylogenetic and mutational studies by others suggest the requirement for Watson-Crick interactions between the nucleotides 505-507 and 524-526 (530 pseudoknot), which are highly conserved. To examine the nature and functional significance of these interactions, a random mutagenesis experiment was conducted in which the nucleotides in the proposed pseudoknot were simultaneously mutated and functional mutants were selected and analyzed. Genetic analysis revealed that the particular nucleotide present at each position except 524 was not exclusively critical to the selection of functional mutants. It also indicated that basepairing interactions between the positions 505-507 and 524-526 were required for ribosomal function, and much weaker base-pairing interactions than those of the wild-type also allowed high ribosomal function. Our results support the hypothesis that the 530 pseudoknot structure may undergo a 'conformational switch' between folded and unfolded states during certain stages of the protein synthesis process by interacting with other ligands present in its environment.