Robust fixed order lateral H-2 controller for micro air vehicle

This paper presents a robust fixed order H-2 controller design using Strengthened discrete optimal projection equations, which approximate the first order necessary optimality condition. The novelty of this work is the application of the robust H-2 controller to a micro aerial vehicle named Sarika2 developed in house. The controller is designed in discrete domain for the lateral dynamics of Sarika2 in the presence of low frequency atmospheric turbulence (gust) and high frequency sensor noise. The design specification includes simultaneous stabilization, disturbance rejection and noise attenuation over the entire flight envelope of the vehicle. The resulting controller performance is comprehensively analyzed by means of simulation.

Experimental Verification of the Lateral Periodicity of Axially Periodic Incoherent Fields Using the Lau Effect

General' objects, which are specially prepared to possess restricted spatial frequency spectra, have been used in the conventional Lau experiment to obtain experimental proof for the existence of lateral periodicity arising from axial periodicity, for a subclass of axially periodic wavefields in an incoherent situation.

Molecular background of three lethal fetal syndromes

This study identified the molecular defects underlying three lethal fetal syndromes. Lethal Congenital Contracture Syndrome 1 (LCCS1, MIM 253310) and Lethal Arthrogryposis with Anterior Horn Cell Disease (LAAHD, MIM 611890) are fetal motor neuron diseases. They affect the nerve cells that control voluntary muscle movement, and eventually result in severe atrophy of spinal cord motor neurons and fetal immobility. Both LCCS1 and LAAHD are caused by mutations in the GLE1 gene, which encodes for a multifunctional protein involved in posttranscriptional mRNA processing. LCCS2 and LCCS3, two syndromes that are clinically similar to LCCS1, are caused by defective proteins involved in the synthesis of inositol hexakisphosphate (IP6), an essential cofactor of GLE1. This suggests a common mechanism behind these fetal motor neuron diseases, and along with accumulating evidence from genetic studies of more late-onset motor neuron diseases such as Spinal muscular atrophy (SMA) and Amyotrophic lateral sclerosis (ALS), implicates mRNA processing as a common mechanism in motor neuron disease pathogenesis. We also studied gle1-/- zebrafish in order to investigate whether they would be a good model for studying the pathogenesis of LCCS1 and LAAHD. Mutant zebrafish exhibit cell death in their central nervous system at two days post fertilization, and the distribution of mRNA within the cells of mutant zebrafish differs from controls, encouraging further studies. The third lethal fetal syndrome is described in this study for the first time. Cocoon syndrome (MIM 613630) was discovered in a Finnish family with two affected individuals. Its hallmarks are the encasement of the limbs under the skin, and severe craniofacial abnormalities, including the lack of skull bones. We showed that Cocoon syndrome is caused by a mutation in the gene encoding the conserved helix-loop-helix ubiquitous kinase CHUK, also known as IκB kinase α (IKKα). The mutation results in the complete lack of CHUK protein expression. CHUK is a subunit of the IκB kinase enzyme that inhibits NF-κB transcription factors, but in addition, it has an essential, independent role in controlling keratinocyte differentiation, as well as informing morphogenetic events such as limb and skeletal patterning. CHUK also acts as a tumor suppressor, and is frequently inactivated in cancer. This study has brought significant new information about the molecular background of these three lethal fetal syndromes, as well as provided knowledge about the prerequisites of normal human development.

Two levels of MCT1 and CD147 expression in the equine red blood cells and muscle

Monocarboxylate transporters (MCTs), especially the isoforms MCT1 - MCT4, cotransport lactate and protons across the cell membranes. They are thus essential for pH regulation and homeostasis in glycolytic cells such as red blood cells (RBCs), and skeletal muscle cells during intense exercise. In 70% of the Standardbred horses the lactate transport activity (TA) in RBCs is high and transport is mediated mainly by MCTs. In the rest 30% of the Standardbreds MCT mediated transport route is not active and the TA is low. MCTs need an ancillary protein for their proper localization and functioning in the plasma membrane. The ancillary protein for MCT1 and MCT4 is a member of immunoglobulin superfamily, CD147. Here we determined the expression of MCT isoforms and CD147 in equine RBCs and gluteal muscle. We sequenced the cDNA of horse MCT1 and CD147 to achieve horse-specific antibodies and to reveal sequence variations that may affect the TA of RBCs. The amount of MCT1 and CD147 mRNA in muscle were also studied. ---- In all, 73 horses representing different breeds were used. Blood samples were drawn from the jugular vein and muscle samples were taken either from gluteal muscle using biopsy needle or during castration from expendable cremaster muscle. The TA of RBCs was studied using radiolabeled lactate and the amount of MCT isoforms and CD147 in the plasma membranes using Western blotting. The level of mRNA in muscle cells was determined using qPCR. Isoforms MCT1 and MCT2 were found in the RBCs and isoforms MCT1 and MCT4 in the muscle cells of horses. The TA of RBCs was dependent on the expression of CD147 and MCT1 in the plasma membrane. Sequence variations were found in the cDNA of both MCT1 and CD147, but they did not explain the inactivity of MCT1 mediated transport route. The single nucleotide polymorphism (SNP) Met125Val in CD147 that existed parallel with an SNP in 3´-untranslated region explained, however, attenuation in CD147 expression in Standardbreds. A single mutation Ile51Val also decreased the expression of CD147 in one Warmblood. The MCT1 and CD147 mRNA concentrations in the gluteal muscle were higher in horses with higher MCT1 and CD147 expression in RBCs and lower in horses with minor expression of CD147 and MCT1. This suggests that the bimodal distribution of TA is due to differences in transcriptional regulation that is functioning in parallel in MCT1 and CD147 gene.

Use of finite wordlength FIR digital filter structures with improved magnitude and phase characteristics for reduction of muscle noise in EEG signals

One of the main disturbances in EEG signals is EMG artefacts generated by muscle movements. In the paper, the use of a linear phase FIR digital low-pass filter with finite wordlength precision coefficients is proposed, designed using the compensation procedure, to minimise EMG artefacts in contaminated EEG signals. To make the filtering more effective, different structures are used, i.e. cascading, twicing and sharpening (apart from simple low-pass filtering) of the designed FIR filter Modifications are proposed to twicing and sharpening structures to regain the linear phase characteristics that are lost in conventional twicing and sharpening operations. The efficacy of all these transformed filters in minimising EMG artefacts is studied, using SNR improvements as a performance measure for simulated signals. Time plots of the signals are also compared. Studies show that the modified sharpening structure is superior in performance to all other proposed methods. These algorithms have also been applied to real or recorded EMG-contaminated EEG signal. Comparison of time plots, and also the output SNR, show that the proposed modified sharpened structure works better in minimising EMG artefacts compared with other methods considered.

Nonlinear Finite-Element Modeling of Batter Piles under Lateral Load

In this paper, a finite-element model is developed in which the nonlinear soil behavior is represented by a hyperbolic relation for static load condition and modified hyperbolic relation, which includes both degradation and gap for a cyclic load condition. Although batter piles are subjected to lateral load, the soil resistance is also governed by axial load, which is incorporated by considering the P-Δ moment and geometric stiffness matrix. By adopting the developed numerical model, static and cyclic load analyses are performed adopting an incremental-iterative procedure where the pile is idealized as beam elements and the soil as elastoplastic spring elements. The proposed numerical model is validated with published laboratory and field pile test results under both static and cyclic load conditions. This paper highlights the importance of the degradation factor and its influence on the soil resistance-displacement (p-y) curve, number of cycles of loading, and cyclic load response.

Robust Fixed Order Lateral H2 Controller for Micro Air Vehicle

This paper presents a robust fixed order H2controller design using strengthened discrete optimal projection equations, which approximate the first order necessary optimality condition. The novelty of this work is the application of the robust H2controller to a micro aerial vehicle named Sarika2 developed in house. The controller is designed in discrete domain for the lateral dynamics of Sarika2 in the presence of low frequency atmospheric turbulence (gust) and high frequency sensor noise. The design specification includes simultaneous stabilization, disturbance rejection and noise attenuation over the entire flight envelope of the vehicle. The resulting controller performance is comprehensively analyzed by means of simulation

Gap model of one-way cyclic lateral load on vertical files in soft clay

For the analysis and design of pile foundation used for coastal structures the prediction of cyclic response, which is influenced by the nonlinear behavior, gap (pile soil separation) and degradation (reduction in strength) of soil becomes necessary. To study the effect of the above parameters a nonlinear cyclic load analysis program using finite element method is developed, incorporating the proposed gap and degradation model and adopting an incremental-iterative procedure. The pile is idealized using beam elements and the soil by number of elastoplastic sub-element springs at each node. The effect of gap and degradation on the load-deflection behavior. elasto-plastic sub-element and resistance of the soil at ground-line have been clearly depicted in this paper.

Nonlinear cyclic load analysis for lateral response of batter piles in soft clay with a rigorous degradation model

Nonlinear analysis of batter piles in soft clay is performed using the finite element technique. As the batter piles are not only governed by lateral load but also axial load, the effect of P- Delta moment and geometric stiffness matrix is included in the analysis. For implementing the nonlinear soil behavior, reduction in soil strength (degradation), and formation of gap with number of load cycles, a numerical model is developed where a hyperbolic relation is adopted for the soil in static condition and hyperbolic relation considering degradation and gap for cyclic load condition. The numerical model is validated with published experimental results for cyclic lateral loading and the hysteresis loops are developed to predict the load-deflection behavior and soil resistance behavior during consecutive cycles of loading. This paper highlights the importance of a rigorous degradation model for subsequent cycles of loading on the pile-soil system by a hysteretic representation.

Transcription factor erect wing (EWG) is involved in indirect flight muscle patterning, development and maintenance in Drosophila

Muscle development is a multistep process which includes myoblast diversification, proliferation, migration, fusion, differentiation and growth. A hierarchical exhibition of myogenic factors is important for dexterous execution of progressive events in muscle formation. EWG (erect wing) is a transcription factor known to have a role in indirect flight muscle development (IFM) in Drosophila. We marked out the precise spatio-temporal expression profile of EWG in the myoblasts, and in the developing muscles. Mutant adult flies null for EWG in myoblasts show variable number of IFM, suggesting that EWG is required for patterning of the IFM. The remnant muscle found in the EWG null flies show proper assembly of the structural proteins, which implies that some myoblasts manage to fuse, develop and differentiate normally indicating that EWG is not required for differentiation program per se. However, when EWG expression is extended beyond its expression window in a wild type background, muscle thinning is observed implying EWG function in protein synthesis inhibition. Mis-expression studies in wing disc myoblasts hinted at its role in myoblast proliferation. We thus conclude that EWG is important for regulating fusion events which in turn decides the IFM pattern. Also IFM in EWG null mutants show clumps containing broken fibres and an altered mitochondrial morphology. The vertebrate homolog of EWG is nuclear respiratory factor1 (NRF1) which is known to have a function in mitochondrial biogenesis and protection against oxidative stress. Gene expression for inner mitochondrial membrane protein, Opa1-like was found to be absent in these mutants. Also, these flies were more sensitive to oxidative stress, indicating a compromised mitochondrial functioning. Our results therefore demonstrate that EWG functions in maintaining muscles’ structural integrity by ensuing proper mitochondrial activity.

On the mass flow rate from silos with lateral exit holes

The mass flow rate, (m) over dot, associated with the lateral outflow of dry, cohesionless granular material through circular orifices of diameter D made in vertical walls of silos was measured experimentally in order to determine also the influence of the wall thickness of the silo, w. Geometrical arguments, based on the outflow happening, are given in order to have a general correlation for (m) over dot embracing both quantities, D and w. The angle of repose appears to be an important characterization factor in these kinds of flows.