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981.
Die Regelung über die Erlangung der Parteistellung übergangener Nachbarn durch Geltendmachung von Einwendungen bis l?ngstens
drei Monate nach dem angezeigten Baubeginn ist wegen der Anknüpfung an einen untauglichen Zeitpunkt verfassungswidrig. 相似文献
982.
M. I. Mazurkov V. S. Dmitrenko S. N. Kropachev 《Radioelectronics and Communications Systems》2008,51(2):106-111
It is proposed a rule of total classes of composition systems of discrete frequency signals (CDF-signals) construction in extended Galois fields. It is carried out modeling and research a correlation properties of CDF-signals, and determined their practical attraction. 相似文献
983.
In this work, the kinetics and mechanism of free-radical polymerisation of glycidyl methacrylate (GMA) using potassium peroxydisulphate
(PDS) as water soluble initiator in the presence of synthesized 1, 4-Bis (tributyl methyl ammonium) benzene dichloride (TBMABDC)
as multi-site phase transfer catalyst (MPTC) was studied. The polymerisation reactions were carried out under inert and unstirred
conditions at constant temperature of 60 ± 1°C in cyclohexane/water biphase media. The role of concentrations of monomer,
initiator, catalyst and volume fraction of aqueous phase, solvent polarity and temperature on the rate of polymerisation (Rp)
was ascertained. The order with respect to monomer and initiator was found to be unity. The order with respect to catalyst
was found to be 0.51. The rate of polymerisation is independent of ionic strength and pH of the medium. However, an increase
in the polarity of solvent has slightly increased the Rp value. Based on the results obtained, a suitable kinetic scheme has
been proposed to account for the experimental observations and its significance discussed. 相似文献
984.
The extraction of Te(IV) from aqueous solutions containing various ligands was studied using various inert organic diluents
and other solvents. The extraction was carried out from solutions of various mineral (HCl, HBr, HI, HNO3) and organic (citric, oxalic) acids of various concentrations. The organic phase was an inert diluent (cyclohexane, CCl4, chloroform, benzene, p-xylene, toluene, nitrobenzene) or a solution of 20 vol % Aliquat-336, 20 vol % trioctylamine, or 30 vol % TBP in p-xylene. A correlation between the distribution of Te(IV) and some physicochemical properties of the diluents and the possibility
of extraction separation radioactive Te isotopes and their daughters, i.e., radioactive I isotopes, were examined. In most
cases, the Te(IV) distribution ratio decreases in the order nitrobenzene > CHCl3 > CCl4 > p-xylene > benzene > toluene > cyclohexane.
Published in Russian in Radiokhimiya, 2007, Vol. 49, No. 4, pp. 353–358.
The text was submitted by the authors in English.
An erratum to this article is available at . 相似文献
985.
A new chromosome encoding method, named fuzzy coding, is proposed for representing real number parameters in a genetic algorithm. Fuzzy coding provides the value of a parameter on the basis of the optimum number of selected fuzzy sets and their effectiveness in terms of degree of membership. Thus, it represents the knowledge associated with each parameter and is an indirect method of encoding compared with alternatives, where the parameters are directly represented in the encoding. Fuzzy coding is described and compared with conventional binary coding, gray coding, and floating-point coding. Two test examples, along with neural identification of a nonlinear pH process from experimental data, are studied. It is shown that fuzzy coding is better than the conventional methods and is effective for parameter optimization in problems where the search space is complicated. 相似文献
986.
Hydrate formation rate plays an important role in making hydrates for the storage and transport of natural gas. Micellar surfactant solutions were found to increase gas hydrate formation rate and storage capacity. With the presence of surfactant, hydrate could form quickly in a quiescent system and the energy costs of hydrate formation reduced. Surfactants (an anionic surfactant, a non‐ionic surfactant and their mixtures) and liquid hydrocarbons (cyclopentane and methylcyclohexane) were used to improve hydrate formation. The experiments of hydrate formation were carried out in the pressure range 3.69–6.82 MPa and the temperature range 274.05–277.55 K. The experimental pressures were kept constant during hydrate formation in each experimental run. The effect of anionic surfactant (sodium dodecyl sulphate (SDS)) on natural gas storage in hydrates is more pronounced compared to a non‐ionic surfactant (dodecyl polysaccharide glycoside (DPG)). The induction time of hydrate formation was reduced with the presence of cyclopentane (CP). Cyclopentane and methylcyclohexane (MCH) could increase hydrate formation rate, but reduced hydrate storage capacity The higher methylcyclohexane concentration, the lower the hydrate storage capacity. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
987.
988.
Hiding biometric data 总被引:5,自引:0,他引:5
Jain A.K. Uludag U. 《IEEE transactions on pattern analysis and machine intelligence》2003,25(11):1494-1498
With the wide spread utilization of biometric identification systems, establishing the authenticity of biometric data itself has emerged as an important research issue. The fact that biometric data is not replaceable and is not secret, combined with the existence of several types of attacks that are possible in a biometric system, make the issue of security/integrity of biometric data extremely critical. We introduce two applications of an amplitude modulation-based watermarking method, in which we hide a user's biometric data in a variety of images. This method has the ability to increase the security of both the hidden biometric data (e.g., eigen-face coefficients) and host images (e.g., fingerprints). Image adaptive data embedding methods used in our scheme lead to low visibility of the embedded signal. Feature analysis of host images guarantees high verification accuracy on watermarked (e.g., fingerprint) images. 相似文献
989.
Finite sample properties of estimators of spatial autoregressive models with autoregressive disturbances 总被引:1,自引:0,他引:1
The article investigates the finite sample properties of estimators for spatial autoregressive models where the disturbance
terms may follow a spatial autoregressive process. In particular we investigate the finite sample behavior of the feasible
generalized spatial two-stage least squares (FGS2SLS) estimator introduced by Kelejian and Prucha (1998), the maximum likelihood
(ML) estimator, as well as that of several other estimators. We find that the FGS2SLS estimator is virtually as efficient
as the ML estimator. This is important because the ML estimator is computationally burdensome, and may even be forbidding
in large samples, while the FGS2SLS estimator remains computationally feasible in large samples.
Received: 20 January 2001 / Accepted: 31 August 2001 相似文献
990.