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51.
We will introduce new functional equations (3) and (4) which are strongly related to well-known formulae (1) and (2) of number
theory, and investigate the solutions of the equations. Moreover, we will also study some stability problems of those equations. 相似文献
52.
53.
We prove that there exists a maximal ideal of a BCI-algebra X in which each subalgebra is an ideal.AMS Subject Classification (1991): 06F35, 03G25.The second author was supported by the LG Yonam Foundation (1995). 相似文献
54.
A graph with n vertices that contains no triangle and no 5-cycle and minimum degree exceeding n/4 contains an independent set with at least (3n)/7 vertices. This is best possible. The proof proceeds by producing a homomorphism to the 7-cycle and invoking the No Homomorphism Lemma. For k ≥ 4, a graph with n vertices, odd girth 2k+1, and minimum degree exceeding n/(k+1) contains an independent set with at least kn/(2k+1) vertices; however, we suspect this is not best possible. © 1993 John Wiley & Sons, Inc. 相似文献
55.
56.
Cyclic and acyclic β-bromovinyl aldehydes are cyclized with an array of arylhydrazines in toluene at 125 °C in the presence of a palladium catalyst and a phosphorus chelating ligand together with NaOtBu to give 1-aryl-1H-pyrazoles in moderate to good yields. 相似文献
57.
In Homma M and Kim SJ [2], the authors considered two-point codes on a Hermitian curve defined over fields of odd characteristic.
In this paper, we study the geometry of a Hermitian curve over fields of even characteristic and classify the two-point codes
whose minimum distances agree with the designed ones. 相似文献
58.
Solid conversion has been of much interest to research workers and the Cumulative Gas Concentration Method (CGCM) has been developed to provide bounds for the reactant solid in irreversible systems having power-law type kinetics. This CGCM is used in conjunction with the Pseudo-Steady-State (PSS) assumption and these bounds appear to be good under certain conditions and for long times.
In this work, the PSS condition is not assumed when deriving the bounds on the cumulative gas concentration and the effect of the inclusion of the transient part is analysed. A technique, based on an iterative scheme incorporating the CGCM, is developed to provide improved estimates for the reactant solid. 相似文献
59.
60.
Sound pressure distributions in the human ear canal, whether unoccluded or occluded with ear molds, were studied using a probe tube technique. On average, for frequencies below 6 kHz, the measuring probe tube had to be placed within 8 mm of the vertical plane containing the top of the eardrum (TOD), determined optically, in order to obtain sound pressure magnitudes within 6 dB of "eardrum pressure." To obtain that accuracy in all of the eight subjects studied, the probe had to be within 6 mm of the TOD. Since probe location relative to the drum has to be known, a purely acoustic method was developed which can be conveniently used to localize the probe-tip position, utilizing the standing wave property of the sound pressure in the ear canal. The acoustically estimated "drum location" generally lay between the optically determined vertical planes containing the TOD and the umbo. On average, the "drum location" fell 1 mm medial to the TOD. Of the 32 estimates made acoustically in various occluded and unoccluded conditions in 14 subjects, 30 estimates lay within a +/- 2-mm range of this average. 相似文献