CFD Investigation of Effect of Depth to Diameter Ratio on Dimple Flow // Computational fluid dynamics investigation of effect of depth to diameter ratio on dimple flow dynamics

This study aimed to further the understanding of laminar flow through a dimple with the goal of mitigating flow separation. Dimples of various depth to diameter ratios (0.05, 0.15) were examined for three different dimple diameters and chordwise locations, corresponding to diameter based (ReD) and chordwise location based (Rex) Reynolds number combinations of ReD 20500\Rex 5000, ReD 20500 Rex 77000, and ReD 9000 Rex 21000. For the last combination, a dimple of depth to diameter ratio of 0.25 was also examined. The dimples were placed in a flat plate located in a diverging channel causing an adverse pressure gradient encouraging flow separation near the dimple location. The flow was modeled in the commercial CFD solver Fluent. Results indicate that dimple depth to diameter ratio has a significant effect on the structure of dimple flow. The shallowest dimples showed little change to the overall flow in the channel. Deeper dimples contained dynamic vortical flow structures with behavior varying between each dimple studied. This dynamic vortex activity was observed to be linked with variances in downstream flow. The 0.15 depth to diameter ratio dimples showed behavior very similar to 0.10 ratio dimples investigated elsewhere. The 0.25 dimple show flow different in nature than 0.15 dimples for the same ReD and Rex; the differences were not as stark as those between 0.05 and 0.15 dimples. In light of this and other studies, dimple flow behavior is found to depend on a combination of parameters that eludes direct quantitative parameterization. However, the conclusion is drawn that the most effective dimple will be just deep enough to develop dynamic vortical activity and vortex shedding

Storage and Analysis of Big Data Tools for Sessionized Data

The Oracle database currently used to mine data at PEGGY is approaching end-of-life and a new infrastructure overhaul is required. It has also been identified that a critical business requirement is the need to load and store very large historical data sets. These data sets contain raw electronic consumer events and interactions from a website such as page views, clicks, downloads, return visits, length of time spent on pages, and how they got to the site / originated. This project will be focused on finding a tool to analyze and measure sessionized data, which is a unit of measurement in web analytics that captures either a user\u27s actions within a particular time period, or the process of segmenting user activity of each user into sessions, each representing a single visit to the site. This sessionized data can be used as the input for a variety of data mining tasks such as clustering, association rule mining, sequence mining etc (Ansari. 2011) This sessionized data must be delivered in a reorganized and readable format timely enough to make informed go-to-market decisions as it relates to the current and existing industry trends. It is also pertinent to understand any development work required and the burden on the resources. Legacy on-premise data warehouse solutions are becoming more expensive, less efficient, less dynamic, and unscalable when compared to current Cloud Infrastructure as a Service (IaaS) that offer real time, on-demand, pay-as-you-go solutions . Therefore, this study will examine the total cost of ownership (TCO) by considering, researching, and analyzing the following factors against a system wide upgrade of the current on-premise Oracle Real Application Cluster (RAC) System: High performance: real-time (or as close to as possible) query speed against sessionized data SQL compliance Cloud based or, at least a hybrid (read: on-premise paired with cloud) Security: encryption preferred Cost structure: cost-effective pay-as-you-go pricing model and resources required for the migration and operations. These technologies analyzed against the current Oracle database are: Amazon Redshift Google Bigquery Hadoop Hadoop + Hive The cost of building an on-premise data warehouse is substantial. The project will determine the performance capabilities and affordability of Amazon Redshift, when compared to other emerging highly ranked solutions, for running e-commerce standard analytics queries on terabytes of sessionized data. Rather than redesigning, upgrading, or over purchasing infrastructure at a high cost for an on-premise data warehouse, this project considers data warehousing solutions through cloud based infrastructure as a service (IaaS) solutions. The proposed objective of this project is to determine the most cost-effective high performer between Amazon Redshift, Apache Hadoop, and Google BigQuery when running e-commerce standard analytics queries on terabytes of sessionized data

Efforts to Reduce International Space Station Crew Maintenance Time in the Management of the Extravehicular Mobility Unit Transport Loop Water Quality

The EMU (Extravehicular Mobility Unit) contains a semi-closed-loop re-circulating water circuit (Transport Loop) to absorb heat into a LCVG (Liquid Coolant and Ventilation Garment) worn by the astronaut. A second, single-pass water circuit (Feed-water Loop) provides water to a cooling device (Sublimator) containing porous plates, and that water sublimates through the porous plates to space vacuum. The cooling effect from the sublimation of this water translates to a cooling of the LCVG water that circulates through the Sublimator. The quality of the EMU Transport Loop water is maintained through the use of a water processing kit (ALCLR - Airlock Cooling Loop Remediation) that is used to periodically clean and disinfect the water circuit. Opportunities to reduce crew time associated with ALCLR operations include a detailed review of the historical water quality data for evidence to support an extension to the implementation cycle. Furthermore, an EMU returned after 2-years of use on the ISS (International Space Station) is being used as a test bed to evaluate the results of extended and repeated ALCLR implementation cycles. Finally, design, use and on-orbit location enhancements to the ALCLR kit components are being considered to allow the implementation cycle to occur in parallel with other EMU maintenance and check-out activities, and to extend the life of the ALCLR kit components. These efforts are undertaken to reduce the crew-time and logistics burdens for the EMU, while ensuring the long-term health of the EMU water circuits for a post- Shuttle 6-year service life

Efforts to Reduce International Space Station Crew Maintenance for the Management of the Extravehicular Mobility Unit Transport Loop Water Quality

The EMU (Extravehicular Mobility Unit) contains a semi-closed-loop re-circulating water circuit (Transport Loop) to absorb heat into a LCVG (Liquid Coolant and Ventilation Garment) worn by the astronaut. A second, single-pass water circuit (Feed-water Loop) provides water to a cooling device (Sublimator) containing porous plates, and that water sublimates through the porous plates to space vacuum. The cooling effect from the sublimation of this water translates to a cooling of the LCVG water that circulates through the Sublimator. The quality of the EMU Transport Loop water is maintained through the use of a water processing kit (ALCLR Airlock Cooling Loop Remediation) that is used to periodically clean and disinfect the water circuit. Opportunities to reduce crew time associated with on-orbit ALCLR operations include a detailed review of the historical water quality data for evidence to support an extension to the implementation cycle. Furthermore, an EMU returned after 2-years of use on the ISS (International Space Station) is being used as a test bed to evaluate the results of extended and repeated ALCLR implementation cycles. Finally, design, use and on-orbit location enhancements to the ALCLR kit components are being considered to allow the implementation cycle to occur in parallel with other EMU maintenance and check-out activities, and to extend the life of the ALCLR kit components. These efforts are undertaken to reduce the crew-time and logistics burdens for the EMU, while ensuring the long-term health of the EMU water circuits for a post-Shuttle 6-year service life

Can Honey Bees Assist in Area Reduction and Landmine Detection?

Honey bees have recently received considerable attention from the popular press as an innovative method to detect a variety of explosives, landmines and UXO. Many of these reports are inaccurate and may encourage individuals and demining groups to “sell” a service that they poorly understand or lack the experience to properly apply. As the developers of this technology, we offer the following summary about the current status of this alternative for landmine detection, including its strengths and limitations

Effects of Wild Pig Disturbance on Forest Vegetation and Soils

In North America, wild pigs (Sus scrofa; feral pigs, feral swine, wild boars) are a widespread exotic species capable of creating large‐scale biotic and abiotic landscape perturbations. Quantification of wild pig environmental effects has been particularly problematic in northern climates, where they occur only recently as localized populations at low densities. Between 2016 and 2017, we assessed short‐term (within ~2 yrs of disturbance) effects of a low‐density wild pig population on forest features in the central Lower Peninsula of Michigan, USA. We identified 16 8‐ha sites using global positioning system locations from 7 radio‐collared wild pigs for sampling.Within each site, we conducted fine‐scale assessments at 81 plots and quantified potential disturbance by wild pigs. We defined disturbance as exposure of overturned soil, often resulting from rooting behavior by wild pigs.We quantified ground cover of plants within paired 1‐m2 frames at each plot, determined effects to tree regeneration using point‐centered quarter sampling, and collected soil cores from each plot. We observed less percent ground cover of native herbaceous plants and lower species diversity, particularly for plants with a coefficient of conservatism ≥5, in plots disturbed by wild pigs.We did not observe an increase in colonization of exotic plants following disturbance, though the observed prevalence of exotic plants was low. Wild pigs did not select for tree species when rooting, and we did not detect any differences in regeneration of light‐ and heavy‐seeded tree species between disturbed or undisturbed plots. Magnesium and ammonium content in soils were lower in disturbed plots, suggesting soil disturbance accelerated leaching of macronutrients, potentially altering nitrogen transformation. Our study suggested that disturbances by wild pigs, even at low densities, alters short‐term native herbaceous plant diversity and soil chemistry. Thus, small‐scale exclusion of wild pigs from vulnerable and rare plant communities may be warranted

Illuminating milling mechanochemistry by tandem real-time fluorescence emission and Raman spectroscopy monitoring

In pursuit of accessible and interpretable methods for direct and real-time observation of mechanochemical reactions, we demonstrate a tandem spectroscopic method for monitoring of ball-milling transformations combining fluorescence emission and Raman spectroscopy, accompanied by high-level molecular and periodic density-functional theory (DFT) calculations, including periodic time-dependent (TD-DFT) modelling of solid-state fluorescence spectra. This proof-of-principle report presents this readily accessible dual-spectroscopy technique as capable of observing changes to the supramolecular structure of the model pharmaceutical system indometacin during mechanochemical polymorph transformation and cocrystallisation. The observed time-resolved in situ spectroscopic and kinetic data are supported by ex situ X-ray diffraction and solid-state nuclear magnetic resonance spectroscopy measurements. The application of first principles (ab initio) calculations enabled the elucidation of how changes in crystalline environment, that result from mechanochemical reactions, affect vibrational and electronic excited states of molecules. The herein explored interpretation of both real-time and ex situ spectroscopic data through ab initio calculations provides an entry into developing a detailed mechanistic understanding of mechanochemical milling processes and highlights the challenges of using real-time spectroscopy

4-Nitro­anilinium triiodide monohydrate

In the title compound, C6H7N2O2 +·I3 −·H2O, the triiodide anions form two-dimensional sheets along the a and c axes. These sheets are separated by the 4-nitro­anilinium cations and water mol­ecules, which form part of an extended hydrogen-bonded chain with the triiodide along the c axis, represented by the graph set C 3 3(14). The second important hydrogen-bonding inter­action is between the nitro group, the water mol­ecule and the anilinium group, which forms an R 2 2(6) ring and may be the reason for the deviation of the torsion angle between the benzene ring and the nitro group from 180 to 163.2 (4)°. These two strong hydrogen-bonding inter­actions also cause the benzene rings to pack off-centre from one another, with an edge-on-edge π–π stacking distance of 3.634 (6) Å and a centroid–centroid separation of 4.843 (2) Å

Behavioral states in space and time: Understanding landscape use by an invasive mammal

Animal movement models can be used to understand species behavior and assist with implementation of management activities. We explored behavioral states of an invasive wild pig (Sus scrofa) population that recently colonized central Michigan, USA, 2014–2018. To quantify environmental factors related to wild pig movement ecology and spatio‐temporal landscape use, we predicted wild pig behavioral states relative to land cover type, landscape structure (i.e., edge and patch cohesion), and weather conditions. We used global positioning system (GPS)‐collars and monitored 8 wild pigs from 2014–2018. We fit local convex hulls and calculated movement metrics revealing 3 wild pig behavioral states (resting, exploratory, and relocating) and constructed a 3‐level model to predict behavioral state probabilities relative to biotic and abiotic conditions. Probabilities of exploratory and resting behaviors were higher nearer to riparian and open herbaceous cover types (oftentimes emergent marsh), indicating that these cover types provided security cover during activity and bedding. Hard mast cover types had a strong positive association with relocating behaviors. More cohesive patches of agriculture and shrub cover types were associated with higher probabilities of exploratory behaviors, while resting was more likely in continuous patches of agriculture (mostly mid‐summer corn). The probability of exploratory behaviors increased exponentially with warming ambient temperature. Our results may be used by managers to develop control strategies conducive to landscape and environmental conditions where the likelihood of encountering wild pigs is highest or targeting wild pigs when in a behavioral state most vulnerable to a particular removal technique