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Signal correlation including antenna coupling

Mutual coupling effects between antenna elements on signal correlation are reported. A simple expression is derived to compute the correlation coefficient from the far-field radiation patterns including the characteristics of the propagation environment and the terminating impedance. It is shown that the mutual coupling between closely spatially separated dipoles call lead to increased signal deco

The Influence of Phantom Size, Shape, and Density, and Collimator Selection on the Dual Photopeak Scatter Correction Method

Results from a Monte Carlo investigation are presented for the application of the dual photopeak window (DPW) scatter correction method to phantom geometries of varying shapes, sizes, and densities as well as to several collimators. A Monte Carlo program was used to simulate a Tc-99m point source at locations of 0.5 cm from the phantom surface, at the center, 0.5 cm from the bottom, and 4/5 the di

Phase Behavior of aqueous polyion-surfactant ion complex salts: Effects of polyion charge density

The effect of varying the fraction of charged monomer units of the polyion in aqueous polyion-oppositely charged surfactant complex salts has been investigated. The complex salts used were based on cetyltrimethylammonium (C(16)TA(+)) with three different polymeric counterions: poly(acrylate) (PA(-)) or poly(acrylate) copolymerized with either dimethylacrylamide (PA(-)/DAM) or N-isopropylamide (PA(

Hamilton's rule confronts ideal free habitat selection

If individuals occupy habitats in a way that maximizes their fitness, if they are free to occupy the habitats they choose and if fitness declines with population density, then their abundance across habitats should follow an ideal free distribution. But, if individuals are genetically related, this simple fitness-maximization mechanism breaks down. Habitat occupation should obey Hamiltons rule (na

Dynamic Traffic Control in Multiservice Networks - Applications of Decision Models

In this thesis, we develop and examine decision models intended for traffic engineering analysis of multiservice networks. Two important issues are addressed, namely call admission and routing control in multiservice broadband networks, and overload control in distributed-memory systems. Multiservice broadband networking generally refers to the ability to handle widely disparate traffic streams s

Steam Drying of Porous Media

The present study concerns heat and mass transfer in porous media dried by superheated steam. Specifically, the steam drying process of a packed bed of porous particles was studied in order to obtain design data for a band drier. The small scale averaged governing equations describing the heat and mass transfer within the porous particles were derived. The inherent transport coefficients were eit

Ethanol from lignocellulosics: A review of the economy

The present study is a review of published investigations regarding the economy of ethanol production from lignocellulosic material The objective is to present relations between and tendencies observed in different cost estimates. The influence of plant capacity and overall product yield on the ethanol production cost is investigated, as well as variations in capital costs in the different process

No title

That the Church of Norway has now adopted gender equality as its policy, is a new situation in a historical perspective, and is the result of a long process within the framework of the state church system. In this context, the way in which the Storting (the Norwegian parliament) dealt with the issue of admitting women to clerical offices in the 1930s was important. The purpose of this thesis has b

Screen-printed carbon electrodes modified with cellobiose dehydrogenase: Amplification factor for catechol vs. reversibility of ferricyanide

A number of screen-printed carbon electrodes (SPCEs) have been electrochemically studied revealing strong correlation between the reversibility of the Fe(CN)/Fe(CN) couple and the sensitivity for catechol at the same electrodes modified with cellobiose dehydrogenase (CDH). Pretreatment of the electrode surfaces increased both the heterogeneous ferricyanide reaction rate and the catechol sensitivit

Lack of an association between Helicobacter infection and autoimmune hepatitis in children

An association between Helicobacter infection and autoimmune hepatitis (AIH) in children was investigated. The prevalence of antibodies to H. pylori did not differ between the AIH and the control group, (22% versus 14%), and antibodies to non-gastric Helicobacter were not detected in either group. H. pylori DNA was found in two AIH liver tissues, but Helicobacter was not cultured from any sample.

Cretaceous palynofloras from southern Scandinavia

Popular Abstract in Swedish Avhandlingen omfattar studiet av fossila pollen och sporer (palynologi) från skånes krita (90-140 miljoner år gamla sediment). För ändamålet har tre borrkärnor provtagits; Höllviken 2, Norrevång 1 och Svedala 1, samt ytprover från överkritan på Bornholm. RESULTAT * Taxonomiska studier baserade på ca 100 arter (ca. 15 000 exemplar), har möjliggjort en stratigrafisk indeA palynological investigation of Cretaceous sequences from Höllviken 2, Svedala 1 and Norrevång 1 wells of Scania, Southern Sweden, and from the Arnager Greensand-Arnager Limestone transition on the island of Bornholm, Denmark, was conducted. Well preserved palynofloras were found in strata consisting of shaly mudstones, glauconitic sandstones (greensand) and limestone. A total of 98 palynomorph t