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41.
关于Vague集的模糊熵及其构造 总被引:17,自引:3,他引:14
本文分析了Vague集的性质,给出了将Vague集变换为Fuzzy集的转换函数,并讨论了其性质。分析了关于Vague集的模糊熵的直观特性,在此基础上我们给出了Vague集的模糊熵的定义。最后给出了一个关于Vague集的模糊熵的构造方法。 相似文献
42.
A statistical method for surveying water quality and analysing the results in terms of quantiles is described. The value of a water quality variable in a grab-sample is taken as a deterministic function of the temporal and spatial coordinates of the sampling point. Quantiles can then be defined for any specified region in time and space as unique, fixed values, and randomly located grab-samples may be used to estimate them for the purposes of describing or regulating water quality. Robust statistical inferences are possible using the binomial distribution. Properties of the quantiles, confidence limits, comparisons with fixed values or between regions, assessment of trends, simultaneous inferences and estimation of sample sizes are discussed. Two examples of water quality surveys, one of Port Phillip Bay, the other of the Maribyrnong River, Victoria, are used to illustrate the theory, paying particular attention to practical problems which arose. The proposed method is compared with others based on stochastic models, and is claimed to be simpler and more reliable. 相似文献
43.
The network model is given and used to calculate the oscillating frequency of thermoacoustic prime mover. Theoretically calculated frequency by the model is plural, whose real part denotes actual frequency of the system, and imaginary part means attenuation coefficient of acoustic pressure. Numerical calculation is made under different conditions including different acoustic cavities, spacing between each parallel plate, gas pressures and system lengths. Theoretically calculated frequency and experimentally measured frequency are in quite good agreement. 相似文献
44.
图像压缩编码方法分析 总被引:1,自引:0,他引:1
介绍图像压缩编码技术发展过程,对图像压缩编码,特别是自适应预测编码、模型法编码、分形编码、小波变换压缩编码、神经网络压缩编码原理和特点进行分析,并阐述图像压缩编码的作用. 相似文献
45.
智能同步光网络(ASON)与多业务传送平台(MSTP)固其先进的智能性、可靠性、灵活性而得以发展和运用。本文根据智能光网络与多业务传送平台枝术的发展情况,结合北京通信传送网络的实际情况,探讨北京通信传送网的建设思路. 相似文献
46.
HLA-DRB1等位基因主要参与人类的抗原免疫功能,对其进行比较研究,有助于追溯人类的进化迁移史,开发类群特异性药物.本研究以Matlab为平台,用自组织竞争网络(Self-Organizing Competitive Neural Network),对世界54个民族和人群、14个HLA-DRB1等位基因,进行了无监督模式分类.结果表明,各民族之间存在差异性,同民族的各人群之间有相似性.西伯利亚各人群,澳洲各土著人群,黑人各人群,南美印第安各人群,犹太族各人群,日本各人群,及欧美白人各人群有相对独立性:南美印第安人与西伯利亚人有高度相似性;中国民族在南方人群和北方人群间存在较大差异;中国汉族中,广东汉族地位特殊,与少数民族如拉祜族、瑶族关系密切. 相似文献
47.
Ana Magalhes Carlos Pinho 《Chemical Engineering and Processing: Process Intensification》2008,47(12):2395-2401
The spouted bed is commonly used to dry granular particles as it displays some special characteristics which render it capable of performing cyclic operations, with particles that are very difficult to fluidize under a different type of bed.Information on the characteristic drying rates of cork stoppers is still very limited in the technical and scientific literature, and until now no published data was found on the spouted bed drying of cork stoppers.The characterization of the drying performance of Port wine cork stoppers was carried out in a laboratory scale spouted bed. Characteristic drying curves were determined with 29 mm × 21 mm cork stoppers under several operating conditions. Values for the effective diffusivity were obtained in the range of 1.36 × 10−9 to 4.44 × 10−9 m2/s, with the temperature dependence represented by an Arrhenius-type relationship. The activation energy obtained was 28.72 kJ/mol. 相似文献
48.
To unlock the full potential of evolution in digital media, a Tierra-like system using network-type assembly-like language
has been constructed. In the system, like Avida, digital creatures, self-replicating programs, live in a discrete 2D torus
space and an interaction between creatures is restricted locally. Bearing a genetic network in mind, network structure is
introduced. In the previous works, it is shown that the possibility that the network-type model has more potential of evolution
than a linear-type model like Avida in a simple environment. In this paper, to study the potential of evolution more precisely,
we model the effects of environment other than creatures. As one of the simplest models of such environment, the cost of execution,
i.e. executing time, is introduced. The difficult environment to live in costs high to execute instructions, the easy environment
does low. In computer experiments, we have investigated the influence of change in environment by analyzing the process of
evolution and diversity of the system. Experimental results show that the network-type system keeps more stable diversity
than the linear-type system does, even when the environment changes drastically. This indicates the possibility that the network-type
system has more potential of evolution than the linear-type system has.
This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January
31–February 2, 2008 相似文献
49.
Chun Lin Ma Qing Feng Wang Rufen Zhang Jikun Li 《Journal of Inorganic and Organometallic Polymers and Materials》2008,18(2):229-235
Six triorganotin(IV) complexes of the type {(R3Sn)2[C3S3(COO)2]}n (R = C6H5 1; n-Bu 2; PhCH2 4; p-F-PhCH2 5; o-F-PhCH2 6) and {(R3Sn)2[C3S3(COO)2]}n·[EtOH] (R = Me 3) have been synthesized by the reaction of bis(carboxymethyl)trithiocarbonate with triorganotin(IV) chloride
in the presence of sodium ethoxide. All complexes were characterized by elemental analysis IR, 1H, 13C and 119Sn NMR spectroscopy. Except for 4–6, all complexes were also characterized by X-ray crystallography. The X-ray date revealed
that complexes 1–3 show two-dimensional network polymeric structure in which the geometries of tin atoms are trigonal bipyramid
with the axial positions occupied by carboxylic oxygen atoms. 相似文献
50.
The article analyzes the influence of the Internet Protocol (IP) access interface on the packet loss probability and delay
times in the optical packet switched network. The network and node model have been proposed, and the structure of the IP access
interface, including assembler and holder, have been included in the analysis. It has been shown that the increase of the
maximum optical packet sizes, as well as use of the holding feature as contention resolution mechanism, decrease the packet
loss probability, but introduce delays at the optical network access points. Modeling and analysis were based on the discrete
event simulation assuming self-similar traffic sources. IP packet lengths were modeled using empirical data.
This work has been conducted while the author was affiliated with the Telecommunication Laboratory, Swiss Federal Institute
of Technology (EPFL-STI-ITOP-TCOM), Lausanne, Switzerland 相似文献