Characterisation of different one-stage blower configurations using 3D unsteady numerical flow simulations

This paper deals with the CFD investigation of the flow in a one-stage radial flow blower-aggregate. The main aim of this numerical study is to compute the relevant operating characteristics of the blower-aggregate and to determine detailed information about the flow characteristics inside it. The distributions of these flow characteristics in the blower determined by the commercial code ANSYS-FLUENT [1] are available to judge whether the elements of the blower are working properly, or not. The calculated characteristics of operating parameters are compared in this paper with measured data given by experimental tests of the blower-aggregate for their validation [2]. The blower-aggregates investigated numerically are noted by BA₁, BA₂ and BA₃ in this paper

PROCESSING OF SLAR IMAGES

An X-band Side Looking Airborne Radar (SLAR) has been developed and constructed. The recorded raw images had to be corrected both radiometrically and geometrically. To achieve this goal, different digital image processing methods have been applied. The obtained results are images fitting well to the original maps of the landscapes. Final resolution of the corrected images is 10 ... 15 m

Contribution of proline to the pre-structuring tendency of transient helical secondary structure elements in intrinsically disordered proteins

Background IDPs function without relying on three-dimensional structures. No clear rationale for such a behavior is available yet. PreSMos are transient secondary structures observed in the target-free IDPs and serve as the target-binding "active" motifs in IDPs. Prolines are frequently found in the flanking regions of PreSMos. Contribution of prolines to the conformational stability of the helical PreSMos in IDPs is investigated. Methods MD simulations are performed for several IDP segments containing a helical PreSMo and the flanking prolines. To measure the influence of flanking-prolines on the structural content of a helical PreSMo calculations were done for wild type as well as for mutant segments with Pro → Asp, His, Lys, or Ala. The change in the helicity due to removal of a proline was measured both for the PreSMo region and for the flanking regions. Results The α-helical content in ~ 70% of the helical PreSMos at the early stage of simulation decreases due to replacement of an N-terminal flanking proline by other residues whereas the helix content in nearly all PreSMos increases when the same replacements occur at the C-terminal flanking region. The helix destabilizing/terminating role of the C-terminal flanking prolines is more pronounced than the helix promoting effect of the N-terminal flanking prolines. General significance This work represents a novel example demonstrating that a proline is encoded in an IDP with a defined purpose. The helical PreSMos presage their target-bound conformations. As they most likely mediate IDP-target binding via conformational selection their helical content can be an important feature for IDP function. © 2013 Elsevier B.V

A Decomposition Approach to Multi-Vehicle Cooperative Control

We present methods that generate cooperative strategies for multi-vehicle control problems using a decomposition approach. By introducing a set of tasks to be completed by the team of vehicles and a task execution method for each vehicle, we decomposed the problem into a combinatorial component and a continuous component. The continuous component of the problem is captured by task execution, and the combinatorial component is captured by task assignment. In this paper, we present a solver for task assignment that generates near-optimal assignments quickly and can be used in real-time applications. To motivate our methods, we apply them to an adversarial game between two teams of vehicles. One team is governed by simple rules and the other by our algorithms. In our study of this game we found phase transitions, showing that the task assignment problem is most difficult to solve when the capabilities of the adversaries are comparable. Finally, we implement our algorithms in a multi-level architecture with a variable replanning rate at each level to provide feedback on a dynamically changing and uncertain environment.Comment: 36 pages, 19 figures, for associated web page see http://control.mae.cornell.edu/earl/decom

Automating, analyzing and improving pupillometry with machine learning algorithms

The investigation of the pupillary light reflex (PLR) is a well-known method to provide information about the functionality of the autonomic nervous system. Pupillometry, a non-invasive technique, was applied to study the PLR alterations in a new, schizophrenia-like rat substrain, named WISKET. The pupil responses to light impulses were recorded with an infrared camera; the videos were automatically processed and features were extracted from the pupillograms. Besides the classical statistical analysis (ANOVA), feature selection and classification were applied to reveal the significant differences in the PLR parameters between the control and WISKET animals. Based on these results, the disadvantages of this method were analyzed and the measurement setup was redesigned and improved. The pupil segmentation method has also been adapted to the new videos. 2564 images were annotated manually and used to train a fully-convolutional neural network to produce pupil mask images. The method was evaluated on 329 test images and achieved 4% median relative error. With the new setup, the pupil detection became reliable and the new data acquisition offers robustness to the experiments

Feature extraction and classification for pupillary images of rats

The investigation of the pupillary light reflex (PLR) is a well-known method to provide information about the functionality of the autonomic nervous system. Pupillometry, a non-invasive technique, was applied in our lab to study the schizophrenia-related PLR alterations in a new selectively bred rat substrain, named WISKET. The pupil responses to light impulses were recorded with an infrared camera; the videos were automatically processed and features were extracted. Besides the classical statistical analysis (ANOVA), feature selection and classification were applied to reveal the significant differences in the PLR parameters between the control and WISKET animals

On the bistable zone of milling processes

A modal-based model of milling machine tools subjected to time-periodic nonlinear cutting forces is introduced. The model describes the phenomenon of bistability for certain cutting parameters. In engineering, these parameter domains are referred to as unsafe zones, where steady-state milling may switch to chatter for certain perturbations. In mathematical terms, these are the parameter domains where the periodic solution of the corresponding nonlinear, time-periodic delay differential equation is linearly stable, but its domain of attraction is limited due to the existence of an unstable quasi-periodic solution emerging from a secondary Hopf bifurcation. A semi-numerical method is presented to identify the borders of these bistable zones by tracking the motion of the milling tool edges as they might leave the surface of the workpiece during the cutting operation. This requires the tracking of unstable quasi-periodic solutions and the checking of their grazing to a time-periodic switching surface in the infinite-dimensional phase space. As the parameters of the linear structural behaviour of the tool/machine tool system can be obtained by means of standard modal testing, the developed numerical algorithm provides efficient support for the design of milling processes with quick estimates of those parameter domains where chatter can still appear in spite of setting the parameters into linearly stable domains

DAAM is required for thin filament formation and Sarcomerogenesis during muscle development in Drosophila.

During muscle development, myosin and actin containing filaments assemble into the highly organized sarcomeric structure critical for muscle function. Although sarcomerogenesis clearly involves the de novo formation of actin filaments, this process remained poorly understood. Here we show that mouse and Drosophila members of the DAAM formin family are sarcomere-associated actin assembly factors enriched at the Z-disc and M-band. Analysis of dDAAM mutants revealed a pivotal role in myofibrillogenesis of larval somatic muscles, indirect flight muscles and the heart. We found that loss of dDAAM function results in multiple defects in sarcomere development including thin and thick filament disorganization, Z-disc and M-band formation, and a near complete absence of the myofibrillar lattice. Collectively, our data suggest that dDAAM is required for the initial assembly of thin filaments, and subsequently it promotes filament elongation by assembling short actin polymers that anneal to the pointed end of the growing filaments, and by antagonizing the capping protein Tropomodulin