Loss factor estimation of the layered panels

The loss factor identification is the effective way to get the proper acoustic analysis in the virtual environment. Using the predictive model is a necessary part of the virtual development. The detection of the inappropriate materials or malfunction designs in the early phase of product development and can dramatically save the cost and development time. The loss factor is the nonlinear parameter for the material modeling of the noise suppression during acoustic analysis. The identification of the loss factor is necessary to perform on the real specimen. The Decay Rate Method is the effective methodology to get accurate results by using standard measuring equipment and is ideal to use in-situ environment. The article describes loss factor identification for plywood material and applications for the automotive industry for glass materials. The complete results analysis is confidential, but the overall procedure of the method is described in specimen analysis

Loss factor estimation of the plywood materials

The acoustic analysis in virtual environment enables the design optimization in the earlier phase of the new product development in term of the noise suppression of the structure. The structural material damping behavior is the most important parameter for the predictive acoustic simulations. The method for the damping loss factor identification involves the measurement of the real specimen and post-processing analysis. The result of the estimation is the structural damping behavior of plywood materials needed for the virtual acoustic analysis

Tools of systematic creativity for increasing of machines and equipment efficiency

Habilitační práce se zabývá problematikou řešení inovačních úloh při zlepšování technických systémů, resp. při zvyšování efektivity strojů a zařízení. V práci jsou stručně představeny a zhodnoceny současné metody řešení inovačních úloh. Konvenční metody nevycházejí ze zákonitostí rozvoje technických systémů, jsou zpravidla založeny na kvantitě vygenerovaných návrhů řešení a dnes již, vzhledem k rychlému rozvoji techniky, neposkytují požadované výsledky. Silná řešitelská metoda TRIZ respektující fyzikální a technické zákonitosti rozvoje technických systémů poskytuje požadované výsledky, ale její aplikace je značně náročná, čímž zabraňuje rozšíření jejího praktického využití. Hlavním cílem práce proto bylo vytvořit zjednodušenou metodu vycházející z metody TRIZ, která systematicky povede řešitele od nejasné problémové situace k formulování inovačního zadání a jeho následnému řešení a bude respektovat zákonitosti rozvoje technických systémů. Na základě studia metody TRIZ, vlastních řešených úloh a zkušeností byla vytvořena metoda nazvaná TRIZ for Efficiency (TfE) sloužící k inovaci strojů a zařízení za účelem zvýšení jejich efektivity i obecně ke zlepšování technických systémů. Aplikace vytvořené metody TfE byla představena na vlastních úlohách zvyšování efektivity zařízení na výrobu nanovláken procesem elektrostatického zvlákňování z volné hladiny roztoku polymeru. Návrhy řešení byly rozpracovány MKP a ověřeny experimentálně. Poskytnutí specifických poznatků ze zvyšování efektivity zařízení na výrobu nanovláken bylo druhým hlavním cílem práce, který byl naplněn představením úloh Inovace zásobníku polymeru, Studie vlivu velikosti elektrod na proces zvlákňování, Inovace přívodem plynného média, Inovace kolektoru typu kartáč a závěrů z nich. Využívání pokročilých systematických metod při zvyšování efektivity strojů a zařízení je vzhledem k jejich rostoucí složitosti stále více žádoucí nejen při procesu inovace konstrukce strojů a zařízení, ale také v procesu jejich údržby. Z toho důvodu byla metoda TfE doplněna přístupem TRIZ for Maintenance (TfMt), zaměřeného na využití nástrojů systematické kreativity v oblasti podnikové údržby. Toto využití je v práci demonstrováno na dílčích příkladech. V závěru práce jsou shrnuty zjištěné obecné i specifické závěry a jsou uvedeny další oblasti, které by bylo vhodné v budoucnu zkoumat.Habilitation thesis is focused on issue of innovation tasks solving at technical systems improving and efficiency increasing of machines and equipment. There are briefly presented and evaluated current methods in the first part of work. Conventional methods are not based on laws of technical systems development, they are generally based on the quantity of generated ideas and currently, due to the rapid development of technology, do not provide the sufficient results. Strong problem solving method TRIZ which respects the laws of physics and technical development of technical systems provide the appropriate results, but its application is very demanding, thus preventing the expansion of its practical use. The main objective of the presented work was to develop a simplified method based on TRIZ method, which systematically lead researcher from the vague formulation of the problem situation to the innovation task and its subsequent solution and will respect the laws of development of technical systems. A new method called TRIZ for Efficiency (TfE) used for innovation of machines and equipment to increase their efficiency and generally to improve technical systems was created based on the studies of TRIZ method, solved tasks and own experience. Application of created method TfE was introduced in tasks focused on efficiency increasing of equipment for nanofibers production using electrospinning process. The concepts have been optimized by FEM and verified experimentally. Second main goal of the work was to provide specific findings in the field of increasing efficiency of equipment for nanofibers production. This was achieved by introducing tasks Innovation of polymer reservoir, Study of the effect of electrode size, Innovation by introducing of blowing gas, Innovation of brush collector) and their conclusions. The use of advanced systematic methods for increasing the efficiency machines and equipment is due to their growing complexity ever more desirable not only at innovation of machnices, but also in the process of their maintenance. For this reason, the method TfE was supported by the approach TRIZ for Maintenance (TfMt), focused on the use of tools of TRIZplus method in maintenance. The usage of TfMt is demonstrated on the particular examples in the work. The general and specific findings and further areas that should be solved in the future are summarized in the conclusion of the work

Enzymatic activity and immunoreactivity of Aca s 4, an alpha-amylase allergen from the storage mite Acarus siro

<p>Abstract</p> <p>Background</p> <p>Enzymatic allergens of storage mites that contaminate stored food products are poorly characterized. We describe biochemical and immunological properties of the native alpha-amylase allergen Aca s 4 from <it>Acarus siro</it>, a medically important storage mite.</p> <p>Results</p> <p><it>A. siro </it>produced a high level of alpha-amylase activity attributed to Aca s 4. This enzyme was purified and identified by protein sequencing and LC-MS/MS analysis. Aca s 4 showed a distinct inhibition pattern and an unusual alpha-amylolytic activity with low sensitivity to activation by chloride ions. Homology modeling of Aca s 4 revealed a structural change in the chloride-binding site that may account for this activation pattern. Aca s 4 was recognized by IgE from house dust mite-sensitive patients, and potential epitopes for cross-reactivity with house dust mite group 4 allergens were found.</p> <p>Conclusions</p> <p>We present the first protein-level characterization of a group 4 allergen from storage mites. Due to its high production and IgE reactivity, Aca s 4 is potentially relevant to allergic hypersensitivity.</p

Modulation of HIV-1 Gag NC/p1 cleavage efficiency affects protease inhibitor resistance and viral replicative capacity

<p>Abstract</p> <p>Background</p> <p>Mutations in the substrate of HIV-1 protease, especially changes in the NC/p1 cleavage site, can directly contribute to protease inhibitor (PI) resistance and also compensate for defects in viral replicative capacity (RC) due to a drug resistant protease. These NC/p1 changes are known to enhance processing of the Gag protein. To investigate the capacity of HIV-1 to modulate Gag cleavage and its consequences for PI resistance and RC, we performed a detailed enzymatic and virological analysis using a set of PI resistant NC/p1 variants (HXB2^431V, HXB2^436E+437T, HXB2^437Tand HXB2^437V).</p> <p>Results</p> <p>Here, we demonstrate that single NC/p1 mutants, which displayed only a slight increase in PI resistance did not show an obvious change in RC. In contrast, the double NC/p1 mutant, which displayed a clear increase in processing efficiency and PI resistance, demonstrated a clear reduction in RC. Cleavage analysis showed that a tridecameric NC/p1 peptide representing the double NC/p1 mutant was cleaved in two specific ways instead of one.</p> <p>The observed decrease in RC for the double NC/p1 mutant (HXB2^436E+437T) could (partially) be restored by either reversion of the 436E change or by acquisition of additional changes in the NC/p1 cleavage site at codon 435 or 438 as was revealed during <it>in vitro </it>evolution experiments. These changes not only restored RC but also reduced PI resistance levels. Furthermore these changes normalized Gag processing efficiency and obstructed the novel secondary cleavage site observed for the double NC/p1 mutant.</p> <p>Conclusions</p> <p>The results of this study clearly demonstrate that HIV-1 can modulate Gag processing and thereby PI resistance. Distinct increases in Gag cleavage and PI resistance result in a reduced RC that can only be restored by amino acid changes in NC/p1 which reduce Gag processing to an optimal rate.</p

Finite element method model of the mechanical behaviour of Jatropha curcas L. bulk seeds under compression loading: Study and 2D modelling of the damage to seeds

This article is focused on comprehensive research of a pressing process ofJatropha curcas L. bulk seeds during linear compression. Compression experiments were performed and the strain and brittle fracturing of the seeds visualised. The mechanical behaviour and stress distribution at the volumetric strain of bulk seeds in pressing cylinders and semi-cylinders with diameters of 60, 80 and 100 mm were described by 2D FEM models. It has been determined that the study of nonlinear visco-elastic and plastic strain seed interactions and the damage and crack growth in such seeds can be significantly improved through computer simulations using an explicit FEM algorithm. In this study, the compressibility of ripe J. curcas L. bulk seeds was analysed and compared depending on the volume strain and energy performance of the linear pressing process. Empirical equations and differential deformation theory describing the seeds interacting beyond the oil point were reported. In addition, the issue of contact theory in numerical modelling of the point contact of interacting seeds was also described. Statistical results showed that the 2D FEM model can be used to study the volumetric strain, stress and damage of J. curcas L. bulk seeds. These studies suggest that FEM models may be considered an important tool to assess the energy performance of the pressing process of J. curcas bulk seeds and can provide valuable information for the design and optimisation of pressing equipment. (C) 2014 IAgrE. Published by Elsevier Ltd. All rights reserved.Ministry of Education, Youth and Sports, Czech Republic [L01201]; "National Programme for Sustainability I"; OPR&DI project Centre for Nanomaterials, Advanced Technologies and Innovation [CZ.1.05/2.1.00/01.0005]; project "Development of Research Teams of R&D Projects at the Technical University of Liberec" [CZ.1.07/2.3.00/30.0024]; CREATex project [CZ.1.07/2.2.00/28.0321]; European Social Fund; Ministry of Education, Youth and Sports, Czech Republic; ESF operational programme "Education for Competitiveness" in the Czech Republic [CZ.1.07/2.3.00/30.0065