A problem based / experiential learning approach to teaching maintenance engineering

Good maintenance practice lies at the heart of a manufacturing industry being able to retain its production capabilities and to ensure the integrity of increasingly complex systems. Consequences of system failure can exceed mere monetary penalties to include the well being of staff. From an engineering education perspective, rapid development in technology in parallel with the evolution of traditional engineering disciplines, necessitates the utilization of innovative ways to teach non-traditional or interdisciplinary topics like maintenance. Another challenge in this context, is the ability to allocate time and physical resources in ever more condensed engineering curricula whilst making the learning process engaging for students. This paper details a recent trial to teach a short undergraduate course on maintenance within a mechanical engineering degree where students also look at some safety considerations associated with maintenance practice. A combined Problem Based Learning/Experiential Learning approach applied to machine tool maintenance was adopted using resources readily available in most engineering schools

The disease of corruption: views on how to fight corruption to advance 21st century global health goals

Corruption has been described as a disease. When corruption infiltrates global health, it can be particularly devastating, threatening hard gained improvements in human and economic development, international security, and population health. Yet, the multifaceted and complex nature of global health corruption makes it extremely difficult to tackle, despite its enormous costs, which have been estimated in the billions of dollars. In this forum article, we asked anti-corruption experts to identify key priority areas that urgently need global attention in order to advance the fight against global health corruption. The views shared by this multidisciplinary group of contributors reveal several fundamental challenges and allow us to explore potential solutions to address the unique risks posed by health-related corruption. Collectively, these perspectives also provide a roadmap that can be used in support of global health anti-corruption efforts in the post-2015 development agenda

Enhanced Position Verification for VANETs using Subjective Logic

The integrity of messages in vehicular ad-hoc networks has been extensively studied by the research community, resulting in the IEEE~1609.2 standard, which provides typical integrity guarantees. However, the correctness of message contents is still one of the main challenges of applying dependable and secure vehicular ad-hoc networks. One important use case is the validity of position information contained in messages: position verification mechanisms have been proposed in the literature to provide this functionality. A more general approach to validate such information is by applying misbehavior detection mechanisms. In this paper, we consider misbehavior detection by enhancing two position verification mechanisms and fusing their results in a generalized framework using subjective logic. We conduct extensive simulations using VEINS to study the impact of traffic density, as well as several types of attackers and fractions of attackers on our mechanisms. The obtained results show the proposed framework can validate position information as effectively as existing approaches in the literature, without tailoring the framework specifically for this use case.Comment: 7 pages, 18 figures, corrected version of a paper submitted to 2016 IEEE 84th Vehicular Technology Conference (VTC2016-Fall): revised the way an opinion is created with eART, and re-did the experiments (uploaded here as correction in agreement with TPC Chairs

Sustainable Policy Design through Integrated Basin Models: Findings from the Rio Grande

In the Rio Grande Basin, water is over-appropriated, and demands for water grow while supplies are constrained by drought and climate change. The Basin is currently in its seventh year of drought, and reservoirs are at historically low levels. Agricultural and municipal river diversions have been sharply curtailed; low flows threaten endangered species. A central policy challenge is the design and implementation of plans that allocate the Basin\u27s water supplies efficiently, fairly, and sustainably. Such plans are complicated by the demands of existing water users, potential new users, three state governments, and two sovereign nations. These challenges are addressed by designing and developing an integrated basin-wide nonlinear programming model to optimize water allocations and use levels for the Basin. The model permits a quantitative testing and analysis of whether institutional adjustments can limit damages caused by drought. It identifies changes in water uses and allocations that result from those adjustments. Compared to existing rules governing the Basin\u27s water use, future drought damages could be reduced by one-fifth to one-third per year from intrastate and interstate water markets coupled with marginal cost pricing, respectively, that permit water transfers across jurisdictions. Results show hydrologic and economic tradeoffs among water uses, regions, and drought control programs

Turning to art as a positive way of living with cancer: A qualitative study of personal motives and contextual influences

Why do some women turn to creative art-making after a diagnosis of cancer? Eleven women provided qualitative accounts that were analyzed following guidelines for interpretative phenomenological analysis (IPA). Some described taking up artistic leisure activities initially in order to manage emotional distress. Others emphasized their need for positive well-being, taking up art to experience achievement and satisfaction, to regain a positive identity, and to normalize family dynamics in the context of living with cancer. Participants’ turn to art-making was facilitated by biographical and contextual factors, including pre-existing craft skills, long-standing personal values and coping philosophies, family role models for managing adversity, and the supportive encouragement of family and friends. Other research has acknowledged that positive lifestyle change and post-traumatic growth can occur after a cancer diagnosis, and this study reveals a multi-faceted process. The findings suggest a need for further research into the experiences that facilitate positive lifestyle change and subjective well-being among people who are living with cancer

An In-Vitro Study to Determine Anti-Caries Efficacy of Fluoride Varnishes

poster abstractFundamental research on fluoride varnishes (FV) and how different formulations affect adherence to teeth, fluoride release into saliva and uptake by teeth is virtually non-existent. The objective of this in vitro study was to investigate the anti-caries efficacy of five commercially available FV: Enamel Pro® Varnish Clear, Flor-Opal® Varnish White, MI Varnish™, PreviDent® and Vanish™. Ninety bovine enamel specimens (4x4mm) were prepared and assigned to five groups (n=18). Early caries lesions were created in the specimens and characterized using Vickers microhardness (VHN). FV was applied to each group of specimens. Immediately afterwards, 7.5ml of artificial saliva (AS) were pipetted over each group, collected and renewed every 15min for 6h. AS samples were analyzed for fluoride using a ion-specific electrode and meter. FV was removed using chloroform and part of the specimens protected to determine enamel fluoride uptake (EFU) using the acid etch technique. Each group was then subjected to pH cycling consisting of a 4h/day acid challenge and two, one-minute treatments with Crest Cavity Protection. Post-pH cycling microhardness was measured and compared to baseline values to determine the ability of the FV to enhance remineralization/prevent demineralization. One-way ANOVA was used for data analysis (p Enamel Pro® (217μg/ml) > Flor-Opal® (153μg/ml) > PreviDent® (84μg/ml) > Vanish(28μg/ml). In conclusion, anti-caries efficacy (measured through EFU, fluoride release and VHN) differs among FV products and this difference may be attributed to different composition, fluoride source and other active ingredients

Determination of Near-Surface Anisotropy From Surface Electromagnetic Data

Ground penetrating radar (GPR) signatures, such as reflection moveout, are sensitive to the presence of azimuthal anisotropy. Azimuthal anisotropy can occur as an intrinsic property of the medium and/or due to the presence of fractures. In such cases, the GPR normal moveout (NMO) velocity, along different orientations of common-midpoint (CMP) gathers, varies with azimuth. This fact is well known in surface reflection seismology. The azimuthal variation of the NMO velocity in an arbitrary medium is elliptical. Considering the analogy between seismic wave propagation in surface seismology and GPR sounding, we can transfer some of the ideas between both fields, including the ellipticity of the NMO velocity in a fractured medium. Here, we discuss briefly GPR reflection moveout in azimuthally anisotropic media. Our study focuses on the transverse mode of electromagnetic wave propagation in which the polarization is normal to the incidence plane of the CMP gathers. A field data example is presented in which three GPR CMP gathers are acquired along three different azimuths, 60° apart, over a fractured medium. Our data analysis demonstrates the azimuthal variation of the GPR NMO velocity, which is utilized to invert for the local orientation of the fracture system in the near surface. The results obtained from the field example agree with the information obtained from geology and near surface studies. This work has important applications in imaging near surface geologic structures and in the determination of tectonic-induced fractures in the near surface.Massachusetts Institute of Technology. Earth Resources LaboratorySaudi Aramc