3,124 research outputs found

    Study On Effect of Boron Carbide, Aluminium Oxide and Graphite On Dry Sliding Wear Behaviour of Aluminium Based Metal Matrix Composite at Different Temperature

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    The present research has been conducted to study the impact of boron carbide (B4C), aluminium oxide(Al2O3) and graphite on Aluminium 2219 (Al2219). According to current research, B4C and graphite material be a good substitute for Al2219.Reinforced composites and unreinforced Al2219 prepared by a stir casting process. A scanning electron microscope was used to analyze the reinforcement and distribution in the matrix and worn surface of the specimen. Exceptional wear resistance (30%) exhibited by  B4C and graphite-reinforced hybrid composite at 150 ºC in contrast with the unreinforced Al2219. The B4C and Gr reinforcement particulate existence improves the strengthening kinetics in the matrix phase at 150 °C. The artificial neural network used to get the test significance, normalized factor importance and absolute relative error of less than 1%

    Working towards fostering programming acceptance in the everyday lives of older and adult people with low levels of formal education:a qualitative case study

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    With the ever-increasing development of digital technologies, understanding their acceptance or rejection is important. A great deal of research, led by the Technology Acceptance Model (TAM), shows that technology acceptance is a hot and complex topic. Much of it has been quantitative and operationalized within mandatory—workplace/organizational—contexts, where instrumental aspects of technology use (e.g., efficiency and productivity) play a central role. In this chapter, we report on a qualitative case study—based on 3 in-person learning courses—of factors that can help us foster programming acceptance in the everyday lives of older and adult people with low levels of formal education. We discuss the relative relevance of technology acceptance constructs, showing that perceived ease-of-use is much less relevant than perceived usefulness, because all participants had to find the fit of programming in their lives. We show that two social aspects—the figure of the course instructor and the group—were key to introduce programming and encourage decision-making. We also discuss some methodological issues, such as the difficulties in asking validated items of TAM (e.g. “I have the knowledge necessary to use the system”) to our participants

    Jetstream: A Distributed Cloud Infrastructure for Under-resourced Higher Education Communities

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    The US National Science Foundation (NSF) in 2015 awarded funding for a first-of-a-kind distributed cyberinfrastructure (DCI) system called Jetstream. Jetstream will be the NSF’s first production cloud for general-purpose science and engineering research and education. Jetstream, scheduled for production in January 2016, will be based on the OpenStack cloud environment software with a menu-driven interface to make it easy for users to select a pre-composed Virtual Machine (VM) to perform a particular discipline-specific analysis. Jetstream will use the Atmosphere user interface developed as part of iPlant, providing a low barrier to use by practicing scientists, engineers, educators, and students, and Globus services from the University of Chicago for seamless integration into the national cyberinfrastructure fabric. The team implementing Jetstream has as their primary mission extending the reach of the NSF’s eXtreme Digital (XD) program to researchers, educators, and research students who have not previously used NSF XD program resources, including those in communities and at institutions that traditionally lack significant cyberinfrastructure resources. We will, for example, use virtual Linux Desktops to deliver DCI capabilities supporting research and research education at small colleges and universities, including Historically Black Colleges and Universities (HBCUs), Minority Serving Institutions (MSIs), Tribal colleges, and higher education institutions in states designated by the NSF as eligible for funding via the Experimental Program to Stimulate Competitive Research (EPSCoR). Jetstream will be a novel distributed cyberinfrastructure, with production components in Indiana and Texas. In particular, Jetstream will deliver virtual Linux desktops to tablet devices and PDAs with reasonable responsiveness running over cellular networks. This paper will discuss design and application plans for Jetstream as a novel Distributed CyberInfrastructure system for research education.National Science Foundation (NSF) grant ACI-1445604. NSF grant OCI-1053575 for campus bridging activitie

    Effect of Boron Carbide on wear resistance of graphite containing Al7029 Based Hybrid Composites and its Dry Sliding Wear Characterization Through Experimental, Response Surface Method and ANOVA

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    Composites are often chosen for tribological applications due to its tailored material properties. The development of hybrid metal matrix composites and the study of their wear behavior has been a prominent focus of materials science research. Present paper deals with fabrication of Al-7029/B4C/Gr hybrid composite using stir casting. Particle distribution and material phase are identified by SEM and XRD. Hardness of the composite increased to 101 BHN while base alloy with 63 BHN. Pin-on-disc Tribometer used to carry wear test and the experimentation conducted by considering three input wear control parameters: 15–35 N (load), 1.5–3.5 m/s (speed) and 200–600 m (distance). Addition of 6%B4C/3%Gr, wear rate of hybrid composites reduced. ANOVA confirmed that load as the most influencing parameter on wear rate. RSM results correlates with mean effect plots of ANOVA and experiments and found that the results are in good compliance. SEM graphs of worn surface confirms that more wear occurred with increased load

    Technology Acceptance of Augmented Reality and Wearable Technologies

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    Augmented Reality and Wearables are the recent media and computing technologies, similar, but different from established technologies, even mobile computing and virtual reality. Numerous proposals for measuring technology acceptance exist, but have not been applied, nor fine-tuned to such new technology so far. Within this contribution, we enhance these existing instruments with the special needs required for measuring technology acceptance of Augmented Reality and Wearable Technologies and we validate the new instrument with participants from three pilot areas in industry, namely aviation, medicine, and space. Findings of such baseline indicate that respondents in these pilot areas generally enjoy and look forward to using these technologies, for being intuitive and easy to learn to use. The respondents currently do not receive much support, but like working with them without feeling addicted. The technologies are still seen as forerunner tools, with some fear of problems of integration with existing systems or vendor-lock. Privacy and security aspects surprisingly seem not to matter, possibly overshadowed by expected productivity increase, increase in precision, and better feedback on task completion. More participants have experience with AR than not, but only few on a regular basis.WEKIT (grant agreement no. 687669

    Estimation of annual risk of tuberculosis infection among children irrespective of BCG scar in the south zone of India

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    Objective: To estimate the proportion infected and compute Annual Risk of Tuberculosis Infection (ARTI) among children irrespective of BCG scar and compare with that among children without BCG scar. Methodology: Tuberculin survey was conducted in south zone of India as a part of the nation-wide survey to estimate the ARTI in different parts of the country and ARTI was computed among children without BCG scar excluding children with BCG scar. In this exercise, the tuberculin test results of children with BCG scar and irrespective of BCG scar were considered for analysis and the results were compared. Results: The prevalence of infection and ARTI estimated among children irrespective of BCG scar aged 1-9 years were 5.7% and 1.0% (95% C.I: 0.8-1.3) respectively. The corresponding figures among unvaccinated children were 5.9% and 1.0% (95% C.I: 0.7-1.4) respectively. The ARTI among children irrespective of BCG scar were similar to that among unvaccinated children. Conclusion: Estimation of proportion of children infected and computation of ARTI using mirror-image technique could be undertaken among children irrespective of BCG scar among children aged either from 1-9 years or 5-9 years

    Biodegradation and antimicrobial properties of zinc oxide–polymer composite materials for urinary stent applications

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    Research advancements in the field of urinary stents have mainly been in the selection of materials and coatings to address commonly faced problems of encrustation and bacterial adhesion. In this study, polylactic acid (PLA) and polypropylene (PP) were evaluated with zinc oxide (ZnO) coating to assess its ability to reduce or eliminate the problems of encrustation and bacteria adhesion. PLA and PP films were prepared via twin screw extrusion. ZnO microparticles were prepared using sol-gel hydrothermal synthesis. The as-prepared ZnO microparticles were combined in the form of a functional coating and deposited on both polymer substrates using a doctor blade technique. The ZnO-coated PP and PLA samples as well as their uncoated counterparts were characterized from the physicochemical standpoints, antibacterial and biodegradation properties. The results demonstrated that both the polymers preserved their mechanical and thermal properties after coating with ZnO, which showed a better adhesion on PLA than on PP. Moreover, the ZnO coating successfully enhanced the antibacterial properties with respect to bare PP/PLA substrates. All the samples were investigated after immersion in simulated body fluid and artificial urine. The ZnO layer was completely degraded following 21 days immersion in artificial urine irrespective of the substrate, with encrustations more evident in PP and ZnO-coated PP films than PLA and ZnO-coated PLA films. Overall, the addition of ZnO coating on PLA displayed better adhesion, antibacterial activity and delayed the deposition of encrustations in comparison to PP substrates

    Translation of evidence-based Assistive Technologies into stroke rehabilitation: Users' perceptions of the barriers and opportunities

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    Background: Assistive Technologies (ATs), defined as "electrical or mechanical devices designed to help people recover movement", demonstrate clinical benefits in upper limb stroke rehabilitation; however translation into clinical practice is poor. Uptake is dependent on a complex relationship between all stakeholders. Our aim was to understand patients', carers' (P&Cs) and healthcare professionals' (HCPs) experience and views of upper limb rehabilitation and ATs, to identify barriers and opportunities critical to the effective translation of ATs into clinical practice. This work was conducted in the UK, which has a state funded healthcare system, but the findings have relevance to all healthcare systems. Methods. Two structurally comparable questionnaires, one for P&Cs and one for HCPs, were designed, piloted and completed anonymously. Wide distribution of the questionnaires provided data from HCPs with experience of stroke rehabilitation and P&Cs who had experience of stroke. Questionnaires were designed based on themes identified from four focus groups held with HCPs and P&Cs and piloted with a sample of HCPs (N = 24) and P&Cs (N = 8). Eight of whom (four HCPs and four P&Cs) had been involved in the development. Results: 292 HCPs and 123 P&Cs questionnaires were analysed. 120 (41%) of HCP and 79 (64%) of P&C respondents had never used ATs. Most views were common to both groups, citing lack of information and access to ATs as the main reasons for not using them. Both HCPs (N = 53 [34%]) and P&C (N = 21 [47%]) cited Functional Electrical Stimulation (FES) as the most frequently used AT. Research evidence was rated by HCPs as the most important factor in the design of an ideal technology, yet ATs they used or prescribed were not supported by research evidence. P&Cs rated ease of set-up and comfort more highly. Conclusion: Key barriers to translation of ATs into clinical practice are lack of knowledge, education, awareness and access. Perceptions about arm rehabilitation post-stroke are similar between HCPs and P&Cs. Based on our findings, improvements in AT design, pragmatic clinical evaluation, better knowledge and awareness and improvement in provision of services will contribute to better and cost-effective upper limb stroke rehabilitation. © 2014 Hughes et al.; licensee BioMed Central Ltd

    The role of brand loyalty and social media in e-commerce interfaces: survey results and implications for user interfaces

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    This paper explores the role of brand loyalty and social media in e-commerce interfaces. A survey consisting of 118 respondents was contacted to address the questions relating to online shopping and brand loyalty. Link between the frequency of access and time spent on an e-commerce user interface, and brand loyalty, gender and age profile differences, and the role of social media to branding and on-line shopping was analyzed. It was found that online loyalty differs from offline loyalty and loyalty also differed across genders, showing men were more loyal than women when shopping online. Information shared about products on social media by friends and family played an important role in purchase decision making. Website interface and ease of navigation were also key aspects for online shopping. The research concluded with recommendations to create multimodal websites which are more interactive and targeted so customer experience is enhanced and loyalty is achieved through the use of interactivity and social media
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