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

Development of the myelin sheath of the hypogastric nerves in a human foetus aged 23 weeks

The formation of the myelin sheath of the human hypogastric nerves was studied by electron microscopy in a foetus of 23 weeks of postovulatory age (220 mm C-R length). In the investigated foetus the hypogastric nerves were mainly composed of bundles of unmyelinated fibres. The myelinated fibres were seen to be at different stages of myelination. Well myelinated fibres had thick compact laminated myelin. The number of myelin lamellae on a single fibre was 22

Reading with hotspots: How young children respond to touchscreen stories

Worldwide estimates indicate that toddlers and preschoolers are introduced to mobile technology at an early age, with many now using touchscreens on a daily basis. One of the appeals of touchscreen technology is that it seems to be intuitive to very young children and, at least from anecdotal evidence, they seem to enjoy it. Even the simplest forms of children's touchscreen media often contain hotspots, which are interactive elements of a screen that allow children to touch a picture and obtain an immediate visual and/or auditory response. Despite the fact that children seem to engage haptically with these technological features, little is known about how they use them and how these features may influence their attention to and comprehension of the media content. A detailed understanding of children's verbal and haptic responses, as well as their visual attention and comprehension, is key to gaining a more complete understanding of children's use of this medium. Using an experimental design, in this pilot study, we examine Dutch preschoolers' (age 2–5, n = 78) haptic use (how much and when they use hotspots), verbal responding (i.e., narrative relevant and irrelevant comments), attention, and story comprehension when hotspots are either activated or turned off. Implications for the use of touchscreen media in early childhood, as well as the design of such media, are offered

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

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