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Nuri Ersoy Tomasz Garstka Kevin Potter Michael R. Wisnom David Porter Graeme Stringer 《Composites Part A》2010,41(3):410-418
In this study, a simple two step finite element model is developed to predict the spring-in of C-sections parts made of AS4/8552 composite. The development of resin properties throughout the MRCC were derived using Group Interaction Modelling and the mechanical properties of the composite predicted by using micromechanical models. Important mechanisms during manufacturing that are effective in the formation of residual stresses and shape distortions are defined. The finite element method implemented is composed of two steps before and after the vitrification of the resin. Vitrification is treated as a point at which the material suddenly changes from the rubbery to glassy state with constant properties in each state. The spring-in angles predicted by the finite element analysis are compared to the angles measured on C-section specimens of various lay-ups and thicknesses. The correlation is good showing the validity of the assumptions adopted. 相似文献
146.
Andrzej Wrbel ukasz Zapaa Tomasz Kluz Artur Rogowski Marcin Misiek Kajetan Juszczak Jacek Sieko Daniela Gold Klaudia Stangel-Wjcikiewicz Ewa Poleszak Piotr Radziszewski 《International journal of molecular sciences》2021,22(11)
The purpose of this study was to determine if asiatic acid may act efficiently in the model of cyclophosphamide (CYP)-induced cystitis in rats. We performed experiments after administration of CYP (single dose 200 mg/kg, intraperitoneally), asiatic acid (30 mg/kg/day for 14 consecutive days, by oral gavage), or CYP plus asiatic acid, during which conscious cystometry, measurements of urothelium thickness and bladder edema, as well as selected biomarkers analyses were conducted. In rats that received asiatic acid together with CYP, a drop in bladder basal pressure, detrusor overactivity index, non-voiding contraction amplitude, non-voiding contraction frequency, and the area under the pressure curve were observed, when compared to the CYP group. Furthermore, a significant increase in threshold pressure, voided volume, intercontraction interval, bladder compliance, and volume threshold to elicit NVC were found in that group accordingly. Administration of the asiatic acid successfully restored concentrations of biomarkers both in bladder urothelium (BDNF, CGRP, OCT-3, IL-1β, IL-6, NGF, nitrotyrosine, malondialdehyde, TNF-α, SV2A, SNAP23, SNAP25, PAC-1, ORM1, occludin, IGFBP-3, HB-EGF, T–H protein, Z01, and HPX) and detrusor muscle (Rho kinase and VAChT) in CYP-treated rats. Finally, asiatic acid significantly decreased urothelium thickness and bladder oedema. Asiatic acid proved to be a potent and effective drug in the rat model of CYP-induced cystitis. 相似文献
147.
Tomasz Patyk Perttu Salmela Teemu Pitkänen Pekka Jääskeläinen Jarmo Takala 《Journal of Signal Processing Systems》2011,65(2):245-259
Field programmable gate array (FPGA) is a flexible solution for offloading part of the computations from a processor. In particular,
it can be used to accelerate an execution of a computationally heavy part of the software application, e.g., in DSP, where
small kernels are repeated often. Since an application code for a processor is a software, a design methodology is needed
to convert the code into a hardware implementation, applicable to the FPGA. In this paper, we propose a design method, which
uses the Transport Triggered Architecture (TTA) processor template and the TTA-based Co-design Environment toolset to automate
the design process. With software as a starting point, we generate a RTL implementation of an application-specific TTA processor
together with the hardware/software interfaces required to offload computations from the system main processor. To exemplify
how the integration of the customized TTA with a new platform could look like, we describe a process of developing required
interfaces from a scratch. Finally, we present how to take advantage of the scalability of the TTA processor to target platform
and application-specific requirements. 相似文献
148.
E. Mingozzi G. Stea M.A. Callejo-Rodríguez J. Enríquez-Gabeiras G. García-de-Blas F.J. Ramón-Salquero W. Burakowski A. Beben J. Sliwinski H. Tarasiuk O. Dugeon M. Diaz L. Baresse E. Monteiro 《Computer Communications》2009,32(12):1355-1370
The EuQoS (End-to-End QoS over Heterogeneous Networks) IST Integrated European Project aimed to define a Next Generation Network architecture that builds, uses and manages end-to-end QoS across different administrative domains and heterogeneous networks (UMTS, xDSL, Ethernet, WiFi, Satellite and IP/MPLS). The EuQoS architecture preserves the openness and the decentralized decision model of the actual Internet, runs on off-the-shelf hardware and network equipment, and allows end users to request various services without changing the Application Signaling protocol, while meeting regulators’ and users’ Net Neutrality requirements. This paper presents the key elements of the EuQoS architecture and describes the main results obtained in field trials performed on a fully-functional EuQoS system prototype developed over a pan-European testbed. Furthermore, the paper discusses the main strengths of the system and the issues related to its actually deployment on a large scale, from both technical and market points of view. 相似文献
149.
Marcin Pisarek Maria Janik-Czachor Tomasz Płociński Mariusz Łukaszewski 《Journal of Materials Science》2009,44(21):5701-5712
Rapidly quenched amorphous alloys—containing metallic or metalloid elements—are precursors for selective catalysts of many
technically important reactions. To increase their activity, various methods of material degradation occurring at the surface
and in the bulk of the rapidly quenched alloys have been used for promoting the catalytic performance of such materials. The
modifications of the structure, composition, and morphology of the substrate proved to be efficient in transforming inactive
metal alloy precursors into active and selective catalysts for hydrogenation, and dehydrogenation of organic compounds, as
well as for other processes like steam reforming of methanol. This article presents several examples of characterization of
such catalysts and discusses their selectivity and activity in a connection with physical and chemical properties of their
surfaces. Moreover, it is shown that scanning electron microscopy, Auger electron spectroscopy, scanning Auger microscopy,
and energy dispersive spectrometry allowed the local changes occurring during the activation process to be identified and
their implications for catalytic function to be considered. 相似文献
150.
Errors in measurements of surface resistanceR
s
of HTS materials are due to discrepancy between a mathematical model describing physical phenomena and a real measurement environment, finite accuracy of measurements of theQ-factor, and finite accuracy of constants used for calculation ofR
s
. In this paper we analyze errors inR
s
due to uncertainties in theQ-factor, geometrical coefficients, loss tangent,R
scu, and other factors when a cylindrical copper cavity with an HTS end plate, a stripline resonator, and sapphire rod resonators are used for HTS characterization. 相似文献