141 research outputs found

    Induction phone charger case

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    This report discusses the project of creating a manual charging phone case for smartphones by means of electromagnetic induction. In today\u27s world, smartphones are being used on the go more often, creating an increased demand for battery life. The capacity of current batteries cannot keep up with the constant usage of data in such activities as emailing, social media, apps, and more. We developed an efficient, ergonomic, and aesthetically pleasing phone case that can manually charge a smartphone without an electrical outlet, but by means of electromagnetic induction. This product would target two main demographics: business people who are constantly on the go, and the outdoors enthusiasts who are not always near an electrical outlet. The product will give users peace of mind knowing that their phone will not die without an outlet or a plug-in phone charger. The phone case would feature a magnet and coil system as an electrical power generator. The magnet and coil will convert energy from mechanical input created by the user spinning a wheel mounted to the rear face of the case. The rotational input of the user is transferred to the generator via a gear train with a final drive ratio of 1:48. With an average input of 4 newtons of force, 2 revolutions per second, and a radius of 2 centimeters of the disc, the mechanical energy provided will create the needed voltage and current for approximately 1 Watt of electrical power. A smartphone draws around 0.4 to 0.5 Watts of power in an idle state, meaning that this 1 Watt will provide the power to overcome idle power draw. We made a simple and intuitive case that features lightweight, ergonomic, and efficient attributes. Physical testing has been conducted on selected generators, yielding promising results. Housing prototypes were 3D printed for fitment testing, while drop tests were conducted theoretically through FEA modelling and testing

    In defence of oxidation states

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    Assessing the Quality of Care for Pneumonia in Integrated Community Case Management: A Cross-Sectional Mixed Methods Study

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    Background Pneumonia is the leading infectious cause of mortality in children under five worldwide. Community-level interventions, such as integrated community case management, have great potential to reduce the burden of pneumonia, as well as other diseases, especially in remote populations. However, there are still questions as to whether community health workers (CHW) are able to accurately assess symptoms of pneumonia and prescribe appropriate treatment. This research addresses limitations of previous studies using innovative methodology to assess the accuracy of respiratory rate measurement by CHWs and provides new evidence on the quality of care given for children with symptoms of pneumonia. It is one of few that assesses CHW performance in their usual setting, with independent re-examination by experts, following a considerable period of time post-training of CHWs. Methods In this cross-sectional mixed methods study, 1,497 CHW consultations, conducted by 90 CHWs in two districts of Luapula province, Zambia, were directly observed, with measurement of respiratory rate for children with suspected pneumonia recorded by video. Using the video footage, a retrospective reference standard assessment of respiratory rate was conducted by experts. Counts taken by CHWs were compared against the reference standard and appropriateness of the treatment prescribed by CHWs was assessed. To supplement observational findings, three focus group discussions and nine in depth interviews with CHWs were conducted. Results and Conclusion The findings support existing literature that CHWs are capable of measuring respiratory rates and providing appropriate treatment, with 81% and 78% agreement, respectively, between CHWs and experts. Accuracy in diagnosis could be strengthened through further training and the development of improved diagnostic tools appropriate for resource-poor settings

    The Fastest Flights in Nature: High-Speed Spore Discharge Mechanisms among Fungi

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    BACKGROUND: A variety of spore discharge processes have evolved among the fungi. Those with the longest ranges are powered by hydrostatic pressure and include "squirt guns" that are most common in the Ascomycota and Zygomycota. In these fungi, fluid-filled stalks that support single spores or spore-filled sporangia, or cells called asci that contain multiple spores, are pressurized by osmosis. Because spores are discharged at such high speeds, most of the information on launch processes from previous studies has been inferred from mathematical models and is subject to a number of errors. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we have used ultra-high-speed video cameras running at maximum frame rates of 250,000 fps to analyze the entire launch process in four species of fungi that grow on the dung of herbivores. For the first time we have direct measurements of launch speeds and empirical estimates of acceleration in these fungi. Launch speeds ranged from 2 to 25 m s(-1) and corresponding accelerations of 20,000 to 180,000 g propelled spores over distances of up to 2.5 meters. In addition, quantitative spectroscopic methods were used to identify the organic and inorganic osmolytes responsible for generating the turgor pressures that drive spore discharge. CONCLUSIONS/SIGNIFICANCE: The new video data allowed us to test different models for the effect of viscous drag and identify errors in the previous approaches to modeling spore motion. The spectroscopic data show that high speed spore discharge mechanisms in fungi are powered by the same levels of turgor pressure that are characteristic of fungal hyphae and do not require any special mechanisms of osmolyte accumulation

    Using Ethnographic Methods to Articulate Community-Based Conceptions of Cultural Heritage Management

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    How can ethnographic methods help communities articulate and enact their own conceptions of heritage management? This and related questions are being explored through an international research project, ‘Intellectual Property Issues in Cultural Heritage’. The project includes up to twenty community- based initiatives that incorporate community-based participatory research and ethnographic methods to explore emerging intellectual property-related issues in archaeological contexts; the means by which they are being addressed or resolved; and the broader implications of these issues and concerns. We discuss three examples that use ethnography to (a) articulate local or customary laws and principles of archaeological heritage management among a First Nations group in British Columbia; (b) assemble knowledge related to land/sea use and cultural practices of the Moriori people of Rekohu (Chatham Islands) for their use in future land and heritage manage- ment policies; and (c) aid a tribal cultural centre in Michigan in crafting co-management strategies to protect spiritual traditions associated with a rock art site on state property. Such situations call for participatory methods that place control over the design, process, products, and interpretation of ‘archaeology’ in the hands of cultural descendants. We hope that these examples of community-based conceptions of archaeological heritage management, facilitated through ethnographic methods and participatory approaches, will increase awareness of the value of these and other alternative approaches and the need to share them widely
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