885 resultados para DUAL-PHASE STEELS
Resumo:
A modified microstrip-fed planar monopole antenna with open circuited coupled line is presented in this paper. The operational bandwidth of the proposed antenna covers the 2.4 GHz ISM band (2.42-2.48 GHz) and the 5 GHz WLAN band (5 GHz to 6 GHz). The radiating elements occupy a small area of 23×8 mm2. The Finite Difference Time Domain method is used to predict the input impedance of the antenna. The calculated return loss shows very good agreement with measured data. Reasonable antenna gain is observed across the operating band. The measured radiation patterns are similar to those of a simple monopole antenna.
Resumo:
Footwear is designed to reduce injury, and enhance performance. However, the effect footwear has on foot and ankle kinematics currently remains unknown. Acknowledging the need for improved understanding, multi-segment models of the foot-shoe complex need to be established to both describe and quantify the effect footwear has on the foot and ankle during stance phase of gait. The purpose of this study was to quantify how footwear alters the kinematics of the foot inside the shoe during stance phase of walking gait.
Resumo:
Footwear is designed to reduce injury and enhance performance. However, the effect footwear has on foot and ankle kinematics currently remains unknown. Acknowledging the need for improved understanding, the aim of this study was to describe the effect footwear has on the kinematics of a multi segment foot during stance phase of walking gait.
Resumo:
Membranes prepared from Bombyx mori silk fibroin have shown potential as a substrate for human limbal epithelial (L-EC) and stromal cell cultivation. Here we present fibroin as a dual-layer construct containing both an epithelium and underlying stroma for corneolimbal reconstruction. We have compared the growth and phenotype of L-EC on non-porous versus porous fibroin membranes. Furthermore, we have compared the growth of limbal mesenchymal stromal cells (L-MSC) in either serum-supplemented medium or the MesenCult-XF® culture system within fibroin fibrous mats. The co-culture of L-EC and L-MSC in fibroin dual-layer constructs was also examined. L-EC on porous membranes displayed a squamous monolayer; in contrast, L-EC on non-porous fibroin appeared cuboidal and stratified. Both constructs maintained evidence of corneal phenotype (cytokeratin 3/12) and distribution of ΔNp63+ progenitor cells. L-MSC cultivated within fibroin fibrous mats in serum-supplemented medium contained less than 64% of cells expressing the characteristic MSC phenotype of CD73+CD90+CD105+ after two weeks, compared with over 81% in MesenCult-XF® medium. Dual-layer fibroin scaffolds consisting of L-EC and L-MSC maintained a similar phenotype as on the separate layers. These results support the feasibility of a 3D engineered limbus constructed from B. mori silk fibroin, and warrant further studies into the potential benefits it offers to corneolimbal tissue regeneration.
Resumo:
This report provides an overview of findings of qualitative research comprising three case studies undertaken as a part of the retrospective analysis component of Sustainable Built Environment National Research Centre (SBEnrc) Project 2.7 Leveraging R&D investment for the Australian Built Environment. These case studies (see Parts 2, 3 and 4 of this suite of reports) were undertaken to illustrate the nature of past R&D investments in Australia. This was done to complement: (i) the audit and analysis of past R&D investment undertaken by Thomas Barlow (2011); and (ii) the Construction 2030 roadmap being developed by Swinburne University of Technology and Professor Göran Roos from VTT Technical Research Centre of Finland. These documents will be the basis for the final phase of the present project - developing policy guidelines for future R&D investment in the Australian built environment. Refer also Parts 1, 2 and 3 for detail findings.
Resumo:
This report discusses findings of a case study into "CADD, BIM and IPD" undertaken as a part of the retrospective analysis component of Sustainable Built Environment National Research Centre (SBEnrc) Project 2.7 Leveraging R&D investment for the Australian Built Environment. This case study investigated the evolution that has taken place in the Queensland Department of Public Works Division of Project Services during the last 20 years from: the initial implementation of computer aided design and documentation(CADD); to the experimentation with building information modelling (BIM) from the mid 2000’s; embedding integrated practice (IP); to current steps towards integrated project delivery (IPD) with the integration of contractors in the design/delivery process. This case study should be read in conjunction with Part 1 of this suite of reports.
Resumo:
This report discusses findings of a case study into "Road Construction Safety" undertaken as a part of the retrospective analysis component of Sustainable Built Environment National Research Centre (SBEnrc) Project 2.7 Leveraging R&D investment for the Australian Built Environment. The Queensland Department of Transport and Main Roads (QTMR) has taken a leadership role in developing a safer working environment for road construction workers. In the past decades, a range of initiatives have been introduced to contribute to improved performance in this area. Several initiatives have been undertaken by QTMR as part of their overarching commitment to safety. Three such initiatives form the basis for this case study investigation, in order to better illustrate the nature of R&D investment and its impact on day-to-day operations and the supply chain. These are the development and implementation of: (i) the Mechanical Traffic Aid: (ii) the Thermal Imaging Camera; and (iii) the Trailer-based CCTV (camera). This case study should be read in conjunction with Part 1 of this suite of reports.
Resumo:
This report discusses findings of a case study into "Green Buildings" undertaken as a part of the retrospective analysis component of Sustainable Built Environment National Research Centre (SBEnrc) Project 2.7 Leveraging R&D investment for the Australian Built Environment. The Western Australian Government (WAG) has taken a leadership role for a number of decades in developing more environmentally responsive buildings. In the past decade, considerable initiatives have been introduced to contribute to: (i) greening the stock of government buildings; and (ii) providing leadership in the development of other non-residential buildings developed commercially. This role has been informed by global, national and internal initiatives and research in this area. This case study investigates: (i) the nature of this leadership; and (ii) the role of R&D policy development; and (iii) the dissemination and impact of outcomes in the broader industry. This case study should be read in conjunction with Part 1 of this suite of reports.
Resumo:
A practical method for the design of dual-band decoupling and matching networks (DMN) for two closely spaced antennas using discrete components is presented. The DMN reduces the port-to-port coupling and enhances the diversity of the antennas. By applying the DMN, the radiation efficiency can also be improved when one port is fed and the other port is match terminated. The proposed DMN works at two frequencies simultaneously without the need for any switch. As a proof of concept, a dual-band DMN for a pair of monopoles spaced 0.05λ apart is designed. The measured return loss and port isolation exceed 10 dB from 1.71 GHz to 1.76 GHz and from 2.27 GHz to 2.32 GHz.
Resumo:
Residual amplitude modulation (RAM) mechanisms in electro-optic phase modulators are detrimental in applications that require high purity phase modulation of the incident laser beam. While the origins of RAMare not fully understood, measurements have revealed that it depends on the beam properties of the laser as well as the properties of the medium. Here we present experimental and theoretical results that demonstrate, for the first time, the dependence of RAM production in electro-optic phase modulators on beam intensity. The results show an order of magnitude increase in the level of RAM, around 10 dB, with a fifteenfold enhancement in the input intensity from 12 to 190 mW/mm 2. We show that this intensity dependent RAM is photorefractive in origin. © 2012 Optical Society of America.
Resumo:
We present experimental and theoretical results of the intensity dependence of residual amplitude modulation (RAM) production in electro-optic phase modulators. By utilizing the anisotropy of the medium, we show that RAM has a photorefractive origin.
Resumo:
Vapour phase assembly has been used for the first time to prepare co-crystals in which the primary intermolecular interaction is halogen bonding. Co-crystals of the nitroxide 1,1,3,3-tetramethylisoindolin-2-yloxyl (TMIO) and 1,2-diiodotetrafluorobenzene (1,2-DITFB) are readily formed under standard sublimation conditions. Single crystal X-ray diffraction confirmed the structure of a 2:2 cyclic tetramer, (TMIO)2·(1,2-DITFB)2, which exhibits a new halogen bonding motif, with each nitroxide oxygen atom accepting two halogen bonds. Powder X-ray diffraction confirmed the homogeneity of the bulk sample. The crystalline complex was further characterized in the solid state using thermal analysis and vibrational spectroscopy (infrared and Raman). Density functional theory calculations were also used to evaluate the enthalpy of formation, electrostatic potential and unpaired electron density of the complex. These findings illustrate the preparation of co-crystals where solution state methodology is problematic and the potential of this approach for the formation of novel organic spin systems.
Resumo:
We examine the solution of the two-dimensional Cahn-Hilliard-reaction (CHR) equation in the xy plane as a model of Li+ intercalation into LiFePO4 material. We validate our numerical solution against the solution of the depth-averaged equation, which has been used to model intercalation in the limit of highly orthotropic diffusivity and gradient penalty tensors. We then examine the phase-change behaviour in the full CHR system as these parameters become more isotropic, and find that as the Li+ diffusivity is increased in the x direction, phase separation persists at high currents, even in small crystals with averaged coherency strain included. The resulting voltage curves decrease monotonically, which has previously been considered a hallmark of crystals that fill homogeneously.
Resumo:
Chronic leg ulcers cause significant pain, cost, decreased quality of life and morbidity for a considerable segment of the older population (Graham et al., 2003a). At any given time the prevalence of patients with open leg ulcers receiving treatment is between 0.11% - 0.18% (Briggs & Closs 2003). Chronic leg ulcers occur in approximately 1 - 2% of the over 60 population in the US, UK, Europe and Australia (Baker & Stacey 1994; Johnson 1995; Lees & Lambert 1992; Margolis et al. 2002). Considerable research has been undertaken to determine the best treatment practices that will aid in the management and the healing of these ulcers, and practical and effective strategies and techniques for healing venous leg ulcers have been trialled to demonstrate their beneficial effects (Nelson et al. 2004; Cullum et al. 2001)...