Brinell Limit Testing Machine - Final Design Report

In keeping with the California Polytechnic State University motto of “Learn by Doing”, this project was performed by Mechanical Engineering students Joe Cloutier, Josh Kessler, and Mike Jaskulsky II as their senior project. Starting in the Fall 2009 quarter and reaching completion with the end of the Spring 2010 quarter, this project provided these students with experience in application of a formal engineering design process in the solving of an open-ended engineering design problem, in developing and maintaining an engineering project schedule, as well as providing further experience working on an engineering team. As the engineers of Parker Aerospace seek to use different metals in their high performance bearing applications than have traditionally been used in the past, often the data does not exist for them to be able to accurately design against brinelling. To provide their engineers with this data, Parker Aerospace proposed the following as a senior project to Cal Poly’s seniors. They requested that a team of engineering students would design, fabricate, assemble, and validate through testing a machine that would determine the loads at the onset of brinelling for different metals and would allow for multiple measurements to be taken from each set of sample materials tested. Some of the secondary design requirements were for the test fixture to be portable, small enough to be used as a desktop unit, be able to accommodate a thermal chamber around the test area, and also provide measurements of the total deformation of the sample materials when under load. Also, time allowing, Parker Aerospace requested that the senior project team devote the last part of the last quarter to using the machine to provide data for a number of materials that they will provide. The loads that the test machine would need to deliver to test all material samples to the onset of brinelling were determined through hertzian contact stress analysis. These calculated loads were then used to determine the deflection of the sample materials, allowing for the sizing of structural components and selection of necessary sensors. The design for the fixture was developed around the initial design concept displayed in the Project Proposal by Parker Aerospace. After developing a number of different designs and variations of specific components of the fixture, the best of these design variations were presented to a panel of Parker Aerospace’s engineers during a Preliminary Design Review. From these designs, a final design was selected and various modifications were made as suggested by Parker. A final design was decided on and the rest of the project was completed by the end of the Spring quarter

Science communication research in the German-speaking countries: A content analysis of conference abstracts

The study examines the state of science communication research in the German-speaking countries. Based on a standardized content analysis of all extended abstracts submitted to the annual conferences of the German Communication Association’s science communication division from 2014 to 2018 (N = 141), it describes the respective scholarly community, its research foci and objects. The results indicate that science communication has developed toward a well-established community and marks an institutionalization of the research field. Furthermore, the findings of the content analysis indicate that science communication research in the German-speaking countries shows parallels to international developments in terms of research foci, objects, and analytical models, but also differences regarding theories and methods

Content Analysis in the Research Field of Science Coverage

Science communication has been defined as encompassing “all forms of communication by and about the sciences, within science (professional audience) as well as in the [broader] public sphere (general audience)”. This broad understanding of science communication includes all kinds of communication focusing on scientific work or scientific results, within science or to non-scientists, in one-directional or dialogical form. It also includes communication about the natural sciences, the arts or the humanities, and it has considerable overlaps with research fields such as health communication and risk communication. Content analysis, especially of media content, is a common method in the research field and this article provides an overview of this research

Improved automated monitoring and new analysis algorithm for circadean phototaxis rhythms in Chlamydomonas

Automated monitoring of circadian rhythms is an efficient way of gaining insight into oscillation parameters like period and phase for the underlying pacemaker of the circadian clock. Measurement of the circadian rhythm of phototaxis (swimming towards light) exhibited by the green alga Chlamydomonas reinhardtii has been automated by directing a narrow and dim light beam through a culture at regular intervals and determining the decrease in light transmittance due to the accumulation of cells in the beam. In this study, the monitoring process was optimized by constructing a new computercontrolled measuring machine that limits the test beam to wavelengths reported to be specific for phototaxis and by choosing an algal strain, which does not need background illumination between test light cycles for proper expression of the rhythm. As a result, period and phase of the rhythm are now unaffected by the time a culture is placed into the machine. Analysis of the rhythm data was also optimized through a new algorithm, whose robustness was demonstrated using virtual rhythms with various noises. The algorithm differs in particular from other reported algorithms by maximizing the fit of the data to a sinusoidal curve that dampens exponentially. The algorithm was also used to confirm the reproducibility of rhythm monitoring by the machine. Machine and algorithm can now be used for a multitude of circadian clock studies that require unambiguous period and phase determinations such as light pulse experiments to identify the photoreceptor(s) that reset the circadian clock in C. reinhardtii

Analyzing science communication through the lens of communication science: reviewing the empirical evidence

From the 1960s onwards, communication scientists have analyzed science communication. This article provides an overview of the empirical evidence that this research has generated. First, it describes the structures of the research field based on available meta-analyses. Then, it describes what is known about the communicators of science (such as scientists, journalists, PR experts, NGOs, and others) and about the portrayals of science in news media as well as online and in social media, and examines what is known about the uses and effects of science communication. For each of these subfields, the questions in focus, typical theoretical approaches, main results, and gaps are identified and reflected upon. In addition, the article identifies research gaps and potential avenues for future research

Water availability, root depths and 2017 crop yields

During 2016 and 2017, June-July precipitation was below normal in many parts of Iowa creating midseason concerns about potential yield loss due to water stress. However, these concerns were not realized. In contrast, 2016 and 2017 crop yields over-performed yields obtained in many years with average of above average June-July precipitation. In Iowa, deep root systems, high soil water storage capacity, and shallow water tables are common explanations for high yields in years with below normal precipitation. How deep can roots grow? How much does groundwater contribute to the yields? To answer these questions and more, the Forecast and Assessment of Cropping sysTemS (FACTS) project was established in 201

The Low-Velocity, Rapidly Fading Type Ia Supernova 2002es

SN 2002es is a peculiar subluminous Type Ia supernova (SN Ia) with a combination of observed characteristics never before seen in a SN Ia. At maximum light, SN 2002es shares spectroscopic properties with the underluminous SN 1991bg subclass of SNe Ia, but with substantially lower expansion velocities (~6000 km/s) more typical of the SN 2002cx subclass. Photometrically, SN 2002es differs from both SN 1991bg-like and SN 2002cx-like supernovae. Although at maximum light it is subluminous (M_B=-17.78 mag), SN 2002es has a relatively broad light curve (Dm15(B)=1.28 +/- 0.04 mag), making it a significant outlier in the light-curve width vs. luminosity relationship. We estimate a 56Ni mass of 0.17 +/- 0.05 M_sun synthesized in the explosion, relatively low for a SN Ia. One month after maximum light, we find an unexpected plummet in the bolometric luminosity. The late-time decay of the light curves is inconsistent with our estimated 56Ni mass, indicating that either the light curve was not completely powered by 56Ni decay or the ejecta became optically thin to gamma-rays within a month after maximum light. The host galaxy is classified as an S0 galaxy with little to no star formation, indicating the progenitor of SN 2002es is likely from an old stellar population. We also present a less extensive dataset for SN 1999bh, an object which shares similar observed properties. Both objects were found as part of the Lick Observatory Supernova Search, allowing us to estimate that these objects should account for ~2.5% of SNe Ia within a fixed volume. We find that current theoretical models are unable to explain the observed of characteristics of SN 2002es.Comment: 19 pages, 15 figures, Submitted to Ap

A quantitative assessment of the annual contribution of platform downwearing to beach sediment budget: Happisburgh, England, UK

Field and numerical investigations at Happisburgh, East coast of England, UK, sought to characterize beach thickness and determine geologic framework controls on coastal change. After a major failure of coastal protection infrastructure, removal of about 1 km of coastal defence along the otherwise protected cliffed coastline of Happisburgh triggered a period of rapid erosion over 20 years of ca. 140 m. Previous sensitivity studies suggest that beach thickness plays a major role in coastal recession. These studies were limited, however, by a lack of beach volume data. In this study, we have integrated the insights gained from our understanding of the Quaternary geology of the area, a novel non-intrusive passive seismic survey method, and a 3D novel representation of the subsurface source and transportable material into a coastal modelling environment to explore the role of beach thickness on the back wearing and downwearing of the cliffs and consolidated platform, respectively. Results show that beach thickness is non-homogeneous along the study site: we estimate that the contribution to near-shore sediment budget via platform downwearing is of a similar order of magnitude as sediment lost from the beach and therefore non-negligible. We have provided a range of evidence to support the idea that the Happisburgh beach is a relatively thin layer perched on a sediment rich platform of sand and gravel. This conceptualization differs from previous publications, which assume that the platform was mostly till and fine material. This has direct implication on regional sediment management along this coastline. The present study contributes to our understanding of a poorly known aspect of coastal sediment budgeting and outlines a quantitative approach that allows for simple integration of geological understanding for coastline evolution assessments worldwid

The WiggleZ Dark Energy Survey: measuring the cosmic expansion history using the Alcock-Paczynski test and distant supernovae

Astronomical observations suggest that today's Universe is dominated by a dark energy of unknown physical origin. One of the most notable consequences in many models is that dark energy should cause the expansion of the Universe to accelerate: but the expansion rate as a function of time has proven very difficult to measure directly. We present a new determination of the cosmic expansion history by combining distant supernovae observations with a geometrical analysis of large-scale galaxy clustering within the WiggleZ Dark Energy Survey, using the Alcock-Paczynski test to measure the distortion of standard spheres. Our result constitutes a robust and non-parametric measurement of the Hubble expansion rate as a function of time, which we measure with 10-15% precision in four bins within the redshift range 0.1 < z < 0.9. We demonstrate that the cosmic expansion is accelerating, in a manner independent of the parameterization of the cosmological model (although assuming cosmic homogeneity in our data analysis). Furthermore, we find that this expansion history is consistent with a cosmological-constant dark energy.Comment: 13 pages, 7 figures, accepted for publication by MNRA

Peaceful Uses Bona Fides: Criteria for Evaluation and Case Studies

This study applies a set of indicators to assess the peaceful nature of a state’s nuclear program. Evaluation of a country’s nuclear program relative to these indicators can help the international community to take appropriate actions to ensure that the growth of the global nuclear energy industry proceeds peacefully and to minimize nuclear proliferation risks