A practical online optimization scheme is developed for performance optimization of an electrical aircraft propulsion system. The goal is to minimize the power extraction of the propulsion system for any given thrust value. The online optimizer computes the optimum pitch angle of a variable pitch propeller by minimizing the power of the system for a command thrust value. This algorithm is teste...

BPM research has been of great importance in Germany since the early 1990s. In Russia, increased competition and new IT possibilities have only recently forced both companies and governmental institutions to start taking benefits from BPM. Against this background, the workshop PropelleR 2012 brought together German and Russian BPM researchers as well as practitioners in order to discuss recent ...

Purpose Q-ball imaging [1] has been proven to have ability of resolving intra-voxel fiber crossings. Compared to DSI (Diffusion Spectrum Imaging) [2] it only requires one-half diffusion-weighted images (515-dirs vs 252-dirs), and takes only about 30 minutes to acquire whole brain data. However 30 minutes acquisition time still hinders its clinical applications. Therefore, we propose PROPELLER Q...

Given a finite family F of axis-parallel boxes in R such that F contains no k + 1 pairwise disjoint boxes, and such that for each two intersecting boxes in F a corner of one box is contained in the other box, we prove that F can be pierced by at most ck log log(k) points, where c is a constant depending only on d. We further show that in some special cases the upper bound on the number of pierc...

It is shown that for every k and every p ≥ q ≥ d + 1 there is a c = c(k, p, q, d) < ∞ such that the following holds. For every family H whose members are unions of at most k compact, convex sets in R in which any set of p members of the family contains a subset of cardinality q with a nonempty intersection there is a set of at most c points in R that intersects each member of H. It is also show...

BACKGROUND Piercings are body embellishments commonly seen in young people, however their inherent risk of infection and scarring disorders are less divulged. OBJECTIVE To evaluate the prevalence of body piercings among medical students and their possible dermatologic consequences. METHODS Cross-sectional study with 58 medical students, by means of a structured questionnaire covering socio-...

Channel wing is a propeller-coupling layout that has good low-speed performance and S/VTOL potential. Focused on the application of this at stage, paper attempts to find interaction mechanism for distributed propeller channel wing. Firstly, computation method based RANS equations propeller–wing integration was established with Momentum Source Method, which compared unsteady Sliding Mesh validat...

An inviscid actuator disk model is embedded in a three-dimensional low-order panel method code for inviscid incompressible flow in order to study the propeller effects on an arbitrary body. The actuator disk model predicts the time–averaged induced velocities in the slipstream of a propeller with an arbitrary radial distribution of load. The model is constructed by superposition of four vortici...

The aim of this study was to estimate the prevalence of life-style practices in adolescents and their association with nickel allergy. Upper secondary school pupils (n = 4,376; 15-23 years) were patch-tested for nickel aller-gy, follow-ing completion of a questionnaire (answered by 6,095). Almost 86% girls and 21% of boys reported piercing. More girls (6%) than boys (3%) had a tattoo. Twenty-si...

Male bed bugs pierce females through the body wall and inseminate directly into the body cavity. It has previously been shown that such traumatic insemination carries costs for females, and sexual conflict regarding the mode of insemination should thus propel male-female coevolution. Since males accumulate sexually antagonistic adaptations, females should evolve counter-adaptations that efficie...