摘要:

The purpose of this study was to characterize students’ knowledge of infinity by investigating the following questions:1.Do students’ responses to infinity tasks vary according to the numerical/geometric context of the task situation?2.Do students’ responses to infinity tasks vary according to the aggregate/serial context of the task situation?3.Do students’ responses to infinity tasks vary according to the convergent/divergent context of the task situation?

ISSN:0972-0502    

DOI:10.1080/09720502.1998.10700241

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

The non-linear differential equation Δu+f(u) = 0 arises in many different physical settings, including nuclear physics, phase transitions in Van der Waals fluids, combustion theory and population genetics. Underlying all of the work that has been done with this problem are the facts that a related ordinary differential equation problem, namely

ISSN:0972-0502    

DOI:10.1080/09720502.1998.10700242

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

An order level inventory system for deteriorating items has been developed with demand rate a ramp type function of time. Deterministic and probabilistic demand situations are discussed. The results obtained have been compared with the corresponding results in the absence of deterioration and finally a numerical example for the deterministic demand situation has been studied along with its sensitivity.

ISSN:0972-0502    

DOI:10.1080/09720502.1998.10700243

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

In this paper a very special fractal, the so-called St. George fractal is investigated. The supposition of the discoverer, that this fractal completely fills out a regular octahedron Unfortunately is wrong.

ISSN:0972-0502    

DOI:10.1080/09720502.1998.10700244

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

LetXbe a random variable with continuous distribution nmctionF(x) on the interval [0,∞), and letX1:n ≤  X2:n ≤  ... ≤  Xn:nbe the order statistics of a random sample of sizen(≥ 2) fromF(x). IfF(x) is continuous and strictly increasing for allx> 0, then for anyiandj, 1 ≤ i< j ≤ n,Xj:n – Xj-i:n-ihave identical distribution characterize the exponential distribution. This characteristic property improve the result of Ahsanullah [2]. In addition, the characterization is preserved ifF(x) is absolutely continuous and “have identical distribution” is weakened to “have identical fmite expectation”.

ISSN:0972-0502    

DOI:10.1080/09720502.1998.10700245

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor