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41.
The asymptotic expected efficiency of distributive sorting is studied showing that for “smooth” key distributions it suffices to consider 2-level methods. The expected cost of sorting n such keys satisfies asymptotically: C(n) ? Kn, where K does not depend on the distribution. 相似文献
42.
Sirpa Peräniemi Sari Hannonen Heikki Mustalahti Markku Ahlgrén 《Fresenius' Journal of Analytical Chemistry》1994,349(7):510-515
The adsorption of arsenic, selenium and mercury from aqueous solutions onto zirconium-loaded activated charcoal was studied as a function of adsorption time, amount of adsorbent, pH, concentration of adsorbates, sample volume and the oxidation states of the adsorbates. The cross-interference of the analytes was also investigated. Loaded filters were measured by energy-dispersive X-ray fluorescence spectrometry (EDXRF) and the amount of the unadsorbed analytes were determined by vapour generation atomic absorption spectrometry (VGAAS). 相似文献
43.
Isoniemi E Khriachtchev L Makkonen M Räsänen M 《The journal of physical chemistry. A》2006,110(40):11479-11487
Photolysis (193 nm) of propiolic acid (HCCCOOH) was studied with Fourier transform infrared spectroscopy in noble-gas (Ar, Kr, and Xe) solid matrixes. The photolysis products were assigned using ab initio quantum chemistry calculations. The novel higher-energy conformer of propiolic acid was efficiently formed upon UV irradiation, and it decayed back to the ground-state conformer on a time scale of approximately 10 min by tunneling of the hydrogen atom through the torsional energy barrier. In addition, the photolysis produced a number of matrix-isolated 1:1 molecular complexes such as HCCH...CO2, HCCOH...CO, and H2O...C3O. The HCCH...CO2 complex dominated among the photolysis products, and the computations suggested a parallel geometry of this complex characterized by an interaction energy of -9.6 kJ/mol. The HCCOH...CO complex also formed efficiently, but its concentration was strongly limited by its light-induced decomposition. In this complex, the most probable geometry was found to feature the interaction of carbon monoxide with the OH group via the carbon atom, and the computational interaction energy was determined to be -18.3 kJ/mol. The formation of the strong H2O...C3O complex (interaction energy -21 kJ/mol) was less efficient, which might be due to the inefficiency of the involved radical reaction. 相似文献
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Markku Liinaharja Shyam S. Chakraborty 《AEUE-International Journal of Electronics and Communications》2002,56(3):177
In this article, an adaptive SR ARQ scheme is analyzed and optimized in a time-varying channel environment with unreliable feedback. Two-state Markov models are assumed for both the forward and the returnchannel.This enables the time behaviour of the entire system to be modelledby a Markov chain. To have an easy-to-implement scheme, we choose the smaller packet size to be half of the bigger one. Thus, there is only oneindependent design parameter related to packet size. The other two parametersare associated with channel sensing. The performance of the adaptive schemeis measured by its average throughput, which is upper-bounded by the throughput of the so-called ideal adaptive scheme. This upper bound is very useful in the optimization of the packet size and other design parameters. From the results, it can be concluded that the selection of the packet size is at least as critical as the optimization of the other parameters. The feedback errors degrade the throughput of the scheme, but their effect on the parameter optimization turns out to be almost negligible. 相似文献
46.
Applying human and pig hepatic in vitro experiments for sulfur mustard study: Screening and identification of metabolites by liquid chromatography/tandem mass spectrometry 下载免费PDF全文
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Lignell A Lundell J Khriachtchev L Räsänen M 《The journal of physical chemistry. A》2008,112(24):5486-5494
The complexes of xenon hydrides HXeY (Y = Cl and Br) with hydrogen halides HX (X = Cl and Br) have been studied both computationally and experimentally in a xenon matrix. The experiments revealed three new complexes: HXeBr...HBr, HXeBr...HCl, and HXeCl...HCl. The experimental assignments were done on the basis of the strong H-Xe stretching absorption of HXeY (Y = Cl and Br) molecules and supported by theoretical results. We experimentally obtained monomer-to-complex blue-shifts of this vibrational mode for all the studied systems (up to approximately 150 cm (-1)). The electronic structure calculations revealed three local structures for each HNgY...HX complexes and their computed interaction energies varied between -460 and -2800 cm (-1). The computational estimates of the vibrational shifts were in agreement with the experimental values. We also found possible experimental absorption belonging to HXeBr...(HBr) 2 trimer and its vibrational shift (+245 cm (-1)) is similar to the computational estimate of a cyclic ternary complex (+252 cm (-1)). 相似文献
50.
Namal Suneth Ahmad Ijaz Saud Saad Jokinen Markku Gurtov Andrei 《Wireless Networks》2016,22(2):663-677
Wireless Networks - The static conventional network architecture is ill-suited to the growing management complexity and highly dynamic wireless network topologies. Software Defined Radio systems... 相似文献