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211.
The purpose of this paper is to show explicitly the spectral density function of the stationary stochastic process determined by a certain class of two-dimensional maps Fα defined below (α is a parameter in (0, 1)), the random variable φ(x, y) = x and the invariant probability described below. We first define the transformation Tα: [0, 1]←[0, 1] given by T α(x) = {x/α if 0 ≤x < α and (α(x?α)/1 ?α) if α≤x≤ 1 where α∈ (0, 1) is a constant. The map Tα describes a model for a particle (or the probability of a certain kind of element in a given population) that moves around, in discrete time, in the interval [0, 1]. The results presented here can be stated either for Tα or for Fα but we prefer the latter. The results for Tα can be obtained from the more general setting described by Fα. The map Fα is defined from K = ([0, 1]× (0, α)) ∨ ([0, α]×[α, 1]) ?;R;2 to itself and is given by Fα(x, y) = (Tα(x), Gα(x, y)) for (x, y) ∈K, where G α(x, y) = {αy if 0 ≤x < α and α + ((1 ?α)/α)y if α≤x < 1. The spectral density function of the stationary process with probability ν (invariant for Fα and absolutely continuous with respect to the Lebesgue measure) Zt = Xt + ξt = φ{Ftα(X0, Y0)} + ξt for t∈Z where (X0, Y0) ∈R2 and ξt}t∈Z is a white noise process, is given explicitly (Theorem 1) by f Z (λ) = fX(λ) + (σ2ξ/2π) = (1/2πvar(Xt))[γ{exp(iλ)}?C(0)] + (σ2/2π) for all λ∈[0, 2π), where var(Xt) = (α2?α + 1)(α2? 5α + 5){12(2 ?α)2}?1, γ is given by Equation (2.10) of Proposition 5 and C(0) = (1 + α2?α3){3(2 ?α)}?1. We also estimate the parameter α based on a time series. 相似文献
212.
Artur Je? 《Information Processing Letters》2009,109(11):543-547
We investigate the problem introduced by Baeza-Yates et al. [R.A. Baeza-Yates, J.C. Culberson, G.J.E. Rawlins, Searching with uncertainty, Research report, University of Waterloo, 1987]: given a plane and a horizontal or a vertical line in unknown location give a strategy to find this line. We use a competitive analysis to measure the performance of this strategy. This problem is one of the first generalisations of the cow search problem. 相似文献
213.
214.
Lech Adamus Beata Orchel Artur Szymański A. Pawe? Wojda Ma?gorzata Zwonek 《Information Processing Letters》2009,110(2):44-45
In this note we present a necessary and sufficient condition for a permutation to be t-complementing which is a natural generalization of the well-known result concerning self-complementing permutations. 相似文献
215.
Applied Multi-Dimensional Fusion 总被引:1,自引:0,他引:1
216.
Nowak P Labus L Stabryla J Durczok A Brus R Nowicka J Shani J 《Receptors & channels》2003,9(5):339-342
The purpose of this study was to investigate how ethanol pretreatment and storage temperatures of brain striatum affect levels of biogenic amines in this tissue. Adult Wistar male rats were injected with 25% ethanol (5.0 g/kg i.p.) while the control rats were administered i.p. with the same volume of saline. Two hours later the rats were decapitated, their brains removed, and the striatum separated. Each striatum was divided into three parts: one part was immediately frozen on dry ice and kept at -70 degrees C; a second fragment was kept in a household refrigerator (+4 degrees C); and the third fragment was kept at +22 degrees C. Twenty-four hours later, levels of DA, DOPAC, HVA, 3-MT, 5-HT, and 5-HIAA in the striatum were assayed by HPLC/ED. Immediately after decapitation; ethanol levels were assayed in the serum of ethanol-pretreated and saline-pretreated rats using gas chromatography. Our results indicate that levels of striatal DA, DOPAC, and HVA in saline-pretreated rats decreased significantly when the storage temperature of the striatum was raised from -70 degrees C, through +4 degrees C, to +22 degrees C, while levels of striatal 5-HT and 5-HIAA remained constant within the temperature range tested and levels of 3-MT fluctuated. In ethanol-pretreated rats, striatal levels of DOPAC, HVA, and 5-HIAA were increased in all three storage temperatures, while levels of DA, 5-HT, and 3-MT were decreased in those temperatures. Those decreases were most profound in striatal samples kept at +22 degrees C. We conclude that concern about possible interactions between drugs and biogenic amines should be exercised. 相似文献
217.
Gabrys J Konecki J Shani J Durczok A Bielaczyc G Kosteczko A Szewczyk H Brus R 《Receptors & channels》2003,9(5):301-307
Levels of 19 proteinous amino acids and of total free amino acids were assayed by gas-liquid chromatography in cytosols of rat atrial and ventricular heart muscle cardiomyocytes. These amino acids were assayed after the rats had been exposed to either exercise (swimming) or hypoxia (hypobaric pressure of 686 hectoPascals). Out of the total free amino acids levels of arginine, glutamine and cysteine in atrial and ventricular cardiac muscle cytosols of control rats were the highest of all amino acids assayed. The control levels of all other amino acids assayed in atrial or ventricular cardiac muscles ranged from 0.1% to 10.6% of the total free amino acids in the control rats. Physical stress (exercise and hypoxia) significantly reduced the total amount of cytosolic free amino acids in both heart muscles. While hypoxia decreased the levels of arginine in both heart muscles, exercise abolished the level of cysteine in the atrial heart muscle. Decrease in arginine levels, and elimination of cysteine from the heart's atrial muscle after physical stress, may be attributed to its utilization of nitric oxide and to its synthesis of atriopeptin and/or endothelin during stress. No change was recorded in either experimental group in the level of glutamine in heart muscle cytosol. Exercise and hypoxia affect, in different modes, the levels of all other amino acids assayed, except for tryptophan, tyrosine, and histidine, which are precursors of endogenous neurotransmitters. The impact of proteinous amino acids on some bodily functions is discussed. 相似文献
218.
De Lamo-Castellví S Roig-Sagués AX Capellas M Hernández-Herrero M Guamis B 《International journal of food microbiology》2005,102(3):337-342
Four human pathogenic strains of Yersinia enterocolitica (serotypes O:1, O:3, O:8, and O:9) were inoculated (7-8 log CFU/ml) in UHT skimmed milk and treated at 300, 400, and 500 MPa for 10 min at 20 degrees C, and then kept at 8 degrees C to assess their evolution for 15 days. Treatments at 400 and 500 MPa caused the highest lethality, generally reaching counts below detection level (1 CFU/ml) in the culture media. At 300 MPa, the most baroresistant serotypes were O:3 and O:8. After 15 days of storage at 8 degrees C, Y. enterocolitica showed growth over 8 log (CFU/ml) in all treatments. Kinetic study of microbial inactivation in skimmed milk was performed with serotype O:8 at 300 MPa, showing a tailing after 35 min of pressure treatment. 相似文献
219.
Artur?HeckerEmail author Houda?Labiod Guy?Pujolle Hossam?Afifi Ahmed?Serhrouchni Pascal?Urien 《Telecommunication Systems》2005,29(2):131-152
The fundamental goal in future 4G mobile multi-service networks is to provide an efficient mobile computing environment. We presume that future terminals will be equipped with multiple heterogeneous wireless interfaces. We want to enable each user to seamlessly move between different providers networks. Besides seamless roaming, a key consideration is also devoted to quality-of-service provision. In this article, we propose a model and an architectural framework for supporting quality of service in the context of interconnected multi-provider wireless systems. The proposed integrated COPS-based management and RADIUS-based access control architecture will allow providers to offer multimedia services while optimizing the use of the underlying network resources. We suggest new concepts and protocols to provide solutions to these challenges and describe the French national research project named MMQoS aiming on building such future networks. 相似文献
220.
Artur Grün 《Electrical Engineering (Archiv fur Elektrotechnik)》1959,44(3):131-146
Inhaltsübersicht Magnetische Erregung und magnetisches Feld von Wirbelstrombremsen—Entstehung der Bremswirkung—Feldverlauf bei Stillstand—Anschluß der Feldgleichungen an die Randbedingungen—Die Verhältnisse bei sehr kleinen Geschwindigkeiten—Aufstellung der Feldgleichungen für den allgemeinen Fall—Bestimmung der Konstanten—Zusammenfassung der Ergebnisse—Berücksichtigung der veränderlichen Permeabilität—Auswertung der Ergebnisse—Beispiel—Literatur.Mit 14 Textabbildungen 相似文献