3,313 research outputs found
Kelly Criterion revisited: optimal bets
Kelly criterion, that maximizes the expectation value of the logarithm of
wealth for bookmaker bets, gives an advantage over different class of
strategies. We use projective symmetries for a explanation of this fact.
Kelly's approach allows for an interesting financial interpretation of the
Boltzmann/Shannon entropy. A "no-go" hypothesis for big investors is suggested.Comment: APFA5 Conference, Torino, 200
K-band high power latching switch
A 19 GHz waveguide latching switch with a bandwidth of 1400 MHz and an exceptionally low insertion loss of 0.25 dB was demonstrated. The RF and driver ferrites are separate structures and can be optimized individually. This analysis for each structure is separately detailed. Basically, the RF section features a dual turnstile junction. The circulator consists of a dielectric tube which contains two ferrite rods, and a dielectric spacer separating the ferrite parts along the center of symmetry of the waveguide to form two turnstiles. This subassembly is indexed and locked in the center of symmetry of a uniform junction of three waveguides by the metallic transformers installed in the top and bottom walls of the housing. The switching junction and its actuating circuitry met all RF performance objectives and all shock and vibration requirements with no physical damage or performance degradation. It exceeds thermal requirements by operating over a 100 C temperature range (-44 C to +56 C) and has a high power handling capability allowing up to 100 W of CW input power
A Sustainable Learning Environment based on an Open-Source Content Management System
This paper presents our approach for supporting face-to-face courses with software components for e-learning based on a general-purpose content management system (CMS). These components—collectively named eduComponents—can be combined with other modules to create tailormade, sustainable learning environments, which help to make teaching and learning more efficient and effective. We give a short overview of these components, and we report on our practical experiences with the software in our courses
Purification and partial characterization of an extracellular melanoprotein from the fungus Venturia inaequalis
The fungus Venturia inaequalis clone No. 36 isolated from Malus domestica cv. Gloster excretes a melanoprotein of 36 kDa in relatively high amounts during growth in liquid culture. The protein was isolated from the culture medium and purified to homogeneity. It was shown to contain melanin. After raising an antiserum against the isolated protein, the protein could be shown to be located in the apoplast fluid of the V. inaequalis infected Malus domestica cv. Elstar. Partial sequencing of the protein revealed no significant sequence homologies to so far sequenced proteins. The melanoprotein binds ferrous and ferric iron. Moreover, it could be shown that the binding of ferric iron (but not of ferrous iron) leads to a change in the absorbance of the protein suggesting a modification of the protein by ferric, but not by ferrous, iron. In addition to iron, the protein also binds copper, but does not bind manganese or nickel. A possible function of this protein in the recruiting and transport of iron and copper and/or in the protection of the fungus by metal-ion mediated oxidative stress is discussed. © 2005 Verlag der Zeitschrift für Naturforschung
Conceptual design of elliptical cavities for intensity and position sensitive beam measurements in storage rings
Position sensitive beam monitors are indispensable for the beam diagnostics
in storage rings. Apart from their applications in the measurements of beam
parameters, they can be used in non-destructive in-ring decay studies of
radioactive ion beams as well as enhancing precision in the isochronous mass
measurement technique. In this work, we introduce a novel approach based on
cavities with elliptical cross-section, in order to compensate for existing
limitations in ion storage rings. The design is aimed primarily for future
heavy ion storage rings of the FAIR project. The conceptual design is discussed
together with simulation results.Comment: Added definition of Uv and Pdiss in the introduction section. Added
Mode numbering in table 1 and figure 1 for more clarity. Corrected one wrong
figure reference. Other minor typo correction
Characterisation of the tetrahalophosphonium cations PBrnI4 − n+ (0 ≤ n ≤ 4) by 31P MAS NMR, IR and Raman spectroscopy and the crystal structures of PI4+AlCl4−, PI4+AlBr4− and PI4+GaI4−
The novel tetrahalophosphonium salts PBr4+AsF6−, PI4+AlCl4− and PI4+EBr4− (E = Al, Ga) have been synthesised. A variety of solid complexes containing PBr4+ (e.g. PBr4+AsF6−, PBr4+AlBr4− PBr4+GaBr4−), PI4+ (e.g. PI4+AlCl4−, PI4+AlBr4−, PI4+GaBr4−) or the mixed species PBrnI4 − n+ (0 ≤ n ≤ 4, containing AlBr4−, GaBr4−, AsF6− or SbF6−) have been studied by solid-state 31P MAS NMR and vibrational spectroscopy. The influence of the counter-ion on the chemical shift and the vibrational frequencies are discussed. The crystal structures of PI4+AlCl4−, PI4+AlBr4− and PI4+GaI4− are reported. Evidence for the existence of the hitherto unknown mixed bromoiodophosphonium cations PBr3I+, PBr2I2+ and PBrI3+ has been confirmed by spin–orbit corrected density functional calculations of isotropic 31P chemical shifts for PBrnI4 − n+
The use of orbitals and full spectra to identify misalignment
In this paper, a SpectraQuest demonstrator is used to introduce misalignment in a rotating set-up. The vibrations caused by misalignment is measured with both accelerometers on the bearings and eddy current probes on the shaft itself. A comparison is made between the classical spectral analysis, orbitals and full spectra. Orbitals are used to explain the physical interpretation of the vibration caused by misalignment. Full spectra allow to distinguish unbalance from misalignment by looking at the forward and reversed phenomena. This analysis is done for different kinds of misalignment, couplings, excitation forces and combined machinery faults
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