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81.
M. Guru Prem Prasad 《Journal of Mathematical Analysis and Applications》2007,329(2):1446-1459
Let E denote the class of all transcendental entire functions for z∈C and an?0 for all n?0 such that f(x)>0 for x<0 and the set of all (finite) singular values of f forms a bounded subset of R. For each f∈E, one parameter family is considered. In this paper, we mainly study the dynamics of functions in the one parameter family S. If f(0)≠0, we show that there exists a positive real number λ∗ (depending on f) such that the bifurcation and the chaotic burst occur in the dynamics of functions in the one parameter family S at the parameter value λ=λ∗. If f(0)=0, it is proved that the Julia set of fλ is equal to the complement of the basin of attraction of the super attracting fixed point 0 for all λ>0. It is also shown that the Fatou set F(fλ) of fλ is connected whenever it is an attracting basin and the immediate basin contains all the finite singular values of fλ. Finally, a number of interesting examples of entire transcendental functions from the class E are discussed. 相似文献
82.
提出了两种适用于光突发交换网的可编程光缓存器结构:交叉型和多端口开关型.两种结构都能满足突发包缓存的超长性和可变性的要求,且结构简单紧凑,成本低,可扩展.交叉型缓存器通过指定信号在每个子缓存模块的光纤环中的循环次数即能实现可变时间的延迟.多端口开关型缓存器通过指定信号在两个多端口开关相应端口与所接光纤延迟线组成的光纤环中的循环次数实现可变时间的延迟.仿真结果表明,两种可编程光缓存器都能对光突发包实现ns级指定时间延迟,可用于解决光突发交换网突发包的冲突问题. 相似文献
83.
Earlier we reported an ion current jump which was observed at a fixed negative biased disc potential in the 6.4GHz ECR ion source at VECC,Kolkata.In a recent experiment with neon ions,we measured the time spectra of the ion current and observed the presence of a burst frequency in the kilohertz range.This frequency shows a correlated jump with the ion current jump described above.Another interesting feature is that the observed burst frequency shows a good linear correlation with the extracted ion current.The higher the ion current,the higher is the burst frequency.This means that current per burst is a constant factor;when there are more number of bursts,the current also increases. 相似文献
84.
ZHANG Qiang ZHOU Jifu & LI Jiachun Institute of Mechanics Chinese Academy of Sciences Beijing 《中国科学G辑(英文版)》2005,48(4):469-484
As one of the important coherent structures in the near-wall region, turbulent burst is responsible for the production and transport of major turbulent kinetic energy and Rey- nolds stress[1]. Nearly half of turbulent kinetic energy or Reynolds stress is produced in the near-wall region, and 80% flows in outer region only contribute 20% of them. Both ejection and sweeping events contribute 60―70% of the turbulent shear stress respec- tively[2]. Recently, turbulent burst process has been foun… 相似文献
85.
A new integrated scheme based on resource-reservation and adaptive network flow routing to alleviate contention in optical burst switching networks is proposed. The objective of the proposed scheme is to reduce the overall burst loss in the network and at the same time to avoid the packet out-of-sequence arrival problem. Simulations are carried out to assess the feasibility of the proposed scheme. Its performance is compared with that of contention resolution schemes based on conventional routing. Through extensive simulations, it is shown that the proposed scheme not only provides significantly better burst loss performance than the basic equal proportion and hop-length based traffic routing algorithms, but also is void of any packet re-orderings. 相似文献
86.
An experimental method has been developed for determining the mechanism of luminescence of crystals by the changes arising in the intensity of a burst of their luminescence under the action of a constant electric field. An example of determining the mechanism of luminescence of AgBr crystals and AgBr0.95 and AgBr0.60Cl0.40 solid solutions by the method proposed is presented. We were the first to establish that the low-temperature photoluminescence of AgBr0.95I0.05 in the band with max = 540 nm proceeds by the Schone–Klasens recombination mechanism. It has also been established that the longwave luminescence of AgBr, AgBr0.95I0.05, and AgBr0.60Cl0.40 in the band with max = 630 nm arises as a result of the recombination of electrons localized on a luminescence center with free holes. 相似文献
87.
对ICP-AES法测定岩石中Ni,Na,V,B,Cu,Fe等元件的方法进行了研究,对仪器的工作参数和共存元素的干扰进行了探讨,采用加基体的标准系列,建立了工作曲线,直接测定岩石中各元素的含量,得到了较好的测定结果。 相似文献
88.
A preliminary study of simulated thermal maturity has been conducted to evaluate the oil, gas and hydrocarbon generation potential of sphagnum coal in the Jinsuo brown coal basin, Yunnan Province and to understand the characteristics of the element composition and biomarkers in the course of thermal alteration. The experimental result was compared with that of xylitic coal, a kind of lithotype of soft brown coal. It is considered that sphagnum coal possesses the potential of forming economic accumulation of oil and gas. Its highest proportion of oil and hydrocarbon generation is 510 mg/g Corg. and 232.1 mg/g Corg. respectively. At an R_(ran)~° value of 2.51%, the ratio of gas generation from sphagnum coal attains to 620.5 ml/g Corg. In view of sphagnum coal being different from the conventional soft brown coal in various respects such as coal forming raw materials and enviroments as well as physico-chemical properties, it is Suggested as a special kind of source rock for coal-generated oil and gas. 相似文献
89.
The heat production of Wistar rat polymorphonuclear leukocytes (PMN) was measured by an LKB 2277 Thermal Activity Monitor. When PMN were activited with phorbol-12-myristate13-acetate (PMA), the respiratory burst was recorded by greatly incr eased heat production. Experiment was also carred out in the present of the inhibitor, Total Flavonoids of Lycium Barbarum L. (TFL). The respiratory burst heat production peak was disappeared, but the heat production curve was higher than that of PMA because TFL increased the metabolic activities of PMN. 相似文献
90.