881 research outputs found

    A new approach to active vibration isolation for microgravity space experiments

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    A new method was developed to design an active vibration isolation system for microgravity space experiments. This method yields the required controller transfer functions for a specified transmissibility ratio. Hence, it is a straightforward task to guarantee that the desired vibration isolation performance is achieved at each frequency. The theory for such a controller design was presented by considering a single degree of freedom system. In addition, the magnitude of the input required by the new method has been found to be less than that used by a standard phase lead/lag compensator

    Use of ePortfolio as Integrated Learning Strategy in Computer Integrated Manufacturing Online Course

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    Integrated learning is a vital strategy for engaging undergraduate Engineering students in the higher levels of learning, as it encourages students to reflect on their learning processes and draw connections between course-work and real-world experiences. Specifically, ePortfolios encourage novice engineers to consider their learning processes over time, drawing connections between coursework and their intended profession, as well as cultivating an online identity that supports their efforts to pursue a career in Engineering. The use of ePortfolios is one method for fostering integrative learning, focusing on the application of digital communication and assessment and awareness of self-competence. By training students to archive digital artifacts related to their learning, ePortfolios encourage student to draw connections between course content and their future careers. Digital portfolios also provide students with the opportunity to develop an online presence, demonstrating through multi-modal content the skills they gained through their education. At the same time, students develop basic digital literacies, from creating and curating digital artifacts throughout the learning process, managing their data, to displaying knowledge and skills which are important for their future engineering careers. This paper examines the efforts of students at Old Dominion University (ODU), Norfolk, Virginia who created ePortfolios in a variety of contexts, as a part of a course which was specifically developed as part of a university wide ePortfolio initiative. In May 2015, faculty attended a professional development workshop, eP3: Praxis, Process, and Production, in order to learn about basic ePortfolio strategies and ways in which to foster students\u27 archival habits. The project presented in this paper was established in the summer 2015 semester in the undergraduate course Computer Integrated Manufacturing at the senior level

    Comparative study of mandibular cortical index in orthopantomogram and bone mineral density of lumbar vertebrae in dual energy x-ray absorptiometry in postmenopausal females in North India.

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    Osteoporosis is a bone disorder which results in low bone mineral content leading to recurrent fractures commonly seen in females after menopause. Few studies have proposed the use of orthopantomogram as a diagnostic marker for osteoporosis as it is simple, quick, easy, inexpensive, non-invasive and widely used. Present study was undertaken to assess the efficacy of OPG to diagnose osteoporosis apropos bone densitometry (DEXA).The study comprised fifty post-menopausal females who were subjected to panoramic radiographs and DEXA. The visual analysis was done based on the radiographic appearance of the lower border of the mandible on the left side by two observers who were blinded about DEXA results. Intra/Inter-observer variability was ruled out by repeated analysis followed by comparison of different grades of MCI (Mandibular Cortical Index) and BMD (Bone Mineral density) statistically. Significant difference in three groups of mandibular cortical index of panoramic radiograph as interpreted by the two observers (p value < 0.05) was found. The intra-observer reproducibility of this index had moderate agreement (Kappa value of 0.35 & 0.31) and the inter-observer agreement of this index followed fair reproducibility (kappa value of 0.38 &0.32). There was significant correlation between results obtained by mandibular cortical index (MCI) and bone mineral density (BMD) of the lumbar vertebrae as determined by the dual energy x-ray absorptiometry implicating visual assessment of the OPG as an important screening tool for osteoporosis in postmenopausal females

    Suicidal Human Poisoning with Fungicide Pencycuron; a Rare Case Report from Rural India with Brief Review of Literature

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    Background: Pencycuron is frequently used worldwide as fungicide.  It is considered to be very effective and safe for humans and its acute toxicity is not yet known. Case Presentation: Here, we describe a case of severe acute Pencycuron poisoning in a young female with suicidal intent. She was immediately hospitalized in ICU and could be saved with meticulous management. Conclusion: Such acute and severe poisoning with Pencycuron has not been reported earlier and to the best of our knowledge this is the first case reported so far

    Embedding Online Based Learning Strategies Into the Engineering Technology Curriculum

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    Various blended learning strategies have been implemented at engineering technology programs to facilitate different learning styles and different time constraints given to faculty. Some of these efforts are related to the effective use of online tools such as online course management systems, ePortfolios, narrated presentations, web-based polling systems, tutorials and educational materials posted before the class and asynchronous learning methods. As technology changes, some of the online learning methods are getting more advanced which is enabling more innovative approaches and data compression. Various distance learning programs started with having access to videos of recorded lectures (on VHS tapes, or CDs) and further they went to use of new media which followed the use of online based strategies such as online management systems, use of social media, podcasts, and other means of communication to deliver the instruction. It became easier to share videos to a wider audiences and enable easier access to state of the art in development in new engineering areas. Accessing pre-recorded educational modules is now easier with new wireless gadgets, with widespread networking capabilities on campuses and outside the campus. In this way, students have opportunities to spend more time in interacting with faculty in class, not only in their assigned office hours. These teaching and learning methods are emphasizing a not so new educational principle, the Socratic method. This concept is especially important for universities with diverse student population which include working adult student population, students who are with the military, students who have families and all other which are non-traditional students who do not live on campus. In this paper, embedding online based learning strategies into the classroom efforts in Engineering Technology department at one midsize institution is discussed

    Addressing New Skills Needed for the Automotive Industry through a Motorsports Educational Pathway

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    The automotive industry has higher-skilled positions available that need engineers and engineering technologists qualified and capable to work in a high-paced, advanced manufacturing sector. Various educational programs across the country offer programs related to the motorsports area at the Associate of Science level. There are also various articu-lation agreements that enable students to continue their education to the baccalaureate level. These programs try to fill in the gap related to the skills shortage in systems and new design methods and processes. The main strength of such educational pathways is that students, who are trained to work as technicians with an associate\u27s degree in automotive and motorsports areas and then continue onto complete their four-year undergraduate degree, have specific skills highly sought by the automotive industry. In this paper, the authors present an example of such an educational pathway, with an emphasis on motorsports

    The correct structures of the ortho-cyclized products in the cycloalkylations of 1-m-methoxybenzyl-4,4a,5,6,7,8-hexahydronaphthalen-2(3H)-one and 1-m-methoxybenzyl-octalins: X-ray structure determination of (±)-4-methoxy-9a-carbamorphinan-16-one

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    The previously assigned (ref.1) ortho-cycloalkylated product from the reaction of 1 and 2 respectively, with ortho-phosphosphoric acid and polyphosphoric acid, has been corrected to (±)-4-methoxy-9a-carbamorphinan-16-one (6) and the respective ether 7 by a single crystal X-ray structure determination of 6

    High pressure-temperature studies on an olivine tholeiite and a tholeiitic picrite from the pavagarh region, Gujarat, India

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    Experimental studies have been performed on an olivine tholeiite and tholeiitic picrite at pressure and temperature ranges of 20-40 kb and 1200-1300°C. The lower and upper limits of basalt-eclogite transition zone for tholeiitic picrite are 23 kb and 31.67 kb at 1200°C, and 24.67 kb and 33.67 kb at 1300°C, whereas for olivine tholeiite, these are 27 kb and 32.33 kb at 1200°C, and 28.70 kb and 33.70 kb at 1300°C. While the assemblages for both samples below the transition region are Pl+Px+Mt, they are Pl+Gt+Px+Mt within it. The eclogite field has Gt+Px+Mt. The ratio of garnet to plagioclase increases from the transition zone to the eclogite field and with the disappearance of plagioclase, the percentage of garnet increases to 30 in the eclogite field. Comparison of our results with previous studies on basalt-eclogite transition shows that the transition zone found by us occurs at higher pressure-temperature conditions. Seismic studies of the region below the Deccan Traps show an increase in velocity (1-4%) at depth. It is suggested that after partial melting, during ascent of the basaltic liquid, a significant portion of it crystallizes within the upper mantle as pockets of eclogite. As eclogite is more dense than peridotite, their presence should cause a similar increase in the seismic velocity below the Deccan area

    Photoluminescence And Raman Studies Of CdS Films Grown By Metal-organic Chemical Vapor Deposition On Si{111} Substrates

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    CdS epitaxial films grown using metal-organic chemical vapor deposition on Si{111} substrates at growth temperatures ranging from 270 to 325 °C have been characterized using photoluminescence and Raman spectroscopy. Out of all the samples the best optical behavior is obtained from that grown at the lowest temperature. Samples grown at the lowest temperature exhibited increased intensity of the bound excitonic peaks and reduced emission at the defect-related luminescence region. The Raman spectra were compatible with the film surface being normal to the c axis, indicating a preferred growth orientation. © 1992
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