Solving the Spruce Creek Problem - Creating a Safer Water System Without Compromising the Environmental Health of a Water System

Spruce Creek is a local river south of Daytona Beach with direct access to the ocean, making it popular for boaters. However, when the Florida East Coast Railway was built, one section was artificially shrunk by building peninsulas to make it easier to build a bridge across. While this saved the railroad money, the modifications caused the river’s current to become dangerously strong, making it difficult (and dangerous) for ocean-going boats to pass through. Efforts by the community to widen the river to make it safer have been complicated by economic and environmental concerns. This study aims to find a solution that satisfies people’s concerns in an economically-feasible manner that preserves the integrity of the ecosystem. This is based on research available on similar situations how solutions affected the ecosystem, studies done on Spruce Creek in previous years, and community information and knowledge on the health of the ecosystem and the difficulty any action may encounter. Each solution is to be analyzed based on 1) how well it satisfies the desires of the community, 2) how much the local or state government will have to spend, and 3) how healthy the river will be in the aftermath. Analysis has been stalled, however, due to the lack of information and difficulty getting information from the local government. When the analysis is complete, the solution can be handed to the local community and used to kickstart efforts to help their community, protecting Spruce Creek and ensuring the health of the water system

Development of ERAU VOLTRON Hybrid-Electric Powerplant

The energy density of today’s batteries is not high enough for electric powered aircraft to achieve an operationally viable range plus FAA stipulated reserve flight times. Hybrid-electric power generation systems may be able to bridge the gap, providing a way for these aircraft to fly distances not possible with batteries alone. There is a recognition that gasoline-electric hybrid systems can deliver specific energy and specific power that are higher than any currently available battery system. Embry-Riddle Aeronautical University’s (ERAU’s) Eagle Flight Research Center (EFRC) is building a 70+ kW hybrid-electric power generation system using a rotary engine and Permanent Magnet Synchronous Machine (PMSM) & Inverter. The rotary engine will be directly coupled to the PMSM which will generate electrical energy to power multi-rotor eVTOL vehicles. These results will be achieved by utilizing advanced control systems implemented on a National Instruments Compact RIO. Past research conducted at the EFRC demonstrated the ability to design and operate a hybrid-electric powerplant. The VOLTRON project will attempt to create a system with an even higher specific energy but with the compact size and high power characteristics of a rotary engine and eventually alternative fuel flexibility

Exotendons for assistance of human locomotion

BACKGROUND: Powered robotic exoskeletons for assistance of human locomotion are currently under development for military and medical applications. The energy requirements for such devices are excessive, and this has become a major obstacle for practical applications. Legged locomotion in many animals, however, is very energy efficient. We propose that poly-articular elastic mechanisms are a major contributor to the economy of locomotion in such specialized animals. Consequently, it should be possible to design unpowered assistive devices that make effective use of similar mechanisms. METHODS: A passive assistive technology is presented, based on long elastic cords attached to an exoskeleton and guided by pulleys placed at the joints. A general optimization procedure is described for finding the best geometrical arrangement of such "exotendons" for assisting a specific movement. Optimality is defined either as minimal residual joint moment or as minimal residual joint power. Four specific exotendon systems with increasing complexity are considered. Representative human gait data were used to optimize each of these four systems to achieve maximal assistance for normal walking. RESULTS: The most complex exotendon system, with twelve pulleys per limb, was able to reduce the joint moments required for normal walking by 71% and joint power by 74%. A simpler system, with only three pulleys per limb, could reduce joint moments by 46% and joint power by 47%. CONCLUSION: It is concluded that unpowered passive elastic devices can substantially reduce the muscle forces and the metabolic energy needed for walking, without requiring a change in movement. When optimally designed, such devices may allow independent locomotion in patients with large deficits in muscle function

Science-rich Sites for In Situ Resource Utilization Characterization and End-to-end Demonstration Missions

Within the European Space Agency’s “Commercial In Situ Resource Utilization (ISRU) Demonstration Mission Preparation Phase,” we examined two types of lunar sites in preparation for an ISRU demonstration mission. First, we considered poorly characterized potential resource sites. For these so-called characterization sites, precursor missions would investigate the material properties and address strategic knowledge gaps for their use as ISRU feedstock. Regions of interest for characterization missions include the Aristarchus plateau, Montes Harbinger/Rimae Prinz, Sulpicius Gallus, and Rima Bode. Regional pyroclastic deposits at the Aristarchus plateau and adjacent Montes Harbinger/Rimae Prinz exhibit remotely sensed low-Ti, high-Fe2+ compositions. They differ from the high-Ti pyroclastics at Rima Bode and Sulpicius Gallus, which are similar to the pyroclastics northwest of the Taurus Littrow valley (Apollo 17 site). Thus, exploration of the Aristarchus plateau would allow investigation of previously uncharacterized materials, whereas Rima Bode or Sulpicius Gallus would allow comparison to Apollo 17 pyroclastics. Any of these sites would enable evaluation of reported H2O/OH in these deposits. Second, we examined a possible site for a direct ISRU demonstrator mission. For a stand-alone end-to-end (E2E) ISRU demonstrator, a fuller understanding of the physical and compositional characteristics of potential feedstock is required for mission risk reduction. In this case, locations near preexisting sites would allow extrapolation of ground truth to nearby deposits. Because a Ti-rich pyroclastic deposit appears advantageous from beneficiation and compositional perspectives, we examine an example E2E demo site northwest of the Taurus Littrow valley. Hydrogen and methane reduction, as well as the Fray–Farthing–Chen Cambridge process, could be tested there.BMWi, 50OW1504, Missionsunterstützende Arbeiten und geologische Untersuchungen der lunaren Oberfläche mit Daten der Lunar Reconnaissance Orbiter Camera (LROC)BMWi, 50OW2001, Missionsunterstützende und wissenschaftliche Arbeiten mit Daten der Lunar Reconnaissance Orbiter Camera (LROC) und Vorbereitung zukünftiger Mondmissione

3D flow in the venom channel of a spitting cobra: do the ridges in the fangs act as fluid guide vanes?

The spitting cobra Naja pallida can eject its venom towards an offender from a distance of up to two meters. The aim of this study was to understand the mechanisms responsible for the relatively large distance covered by the venom jet although the venom channel is only of micro-scale. Therefore, we analysed factors that influence secondary flow and pressure drop in the venom channel, which include the physical-chemical properties of venom liquid and the morphology of the venom channel. The cobra venom showed shear-reducing properties and the venom channel had paired ridges that span from the last third of the channel to its distal end, terminating laterally and in close proximity to the discharge orifice. To analyze the functional significance of these ridges we generated a numerical and an experimental model of the venom channel. Computational fluid dynamics (CFD) and Particle-Image Velocimetry (PIV) revealed that the paired interior ridges shape the flow structure upstream of the sharp 90° bend at the distal end. The occurrence of secondary flow structures resembling Dean-type vortical structures in the venom channel can be observed, which induce additional pressure loss. Comparing a venom channel featuring ridges with an identical channel featuring no ridges, one can observe a reduction of pressure loss of about 30%. Therefore it is concluded that the function of the ridges is similar to guide vanes used by engineers to reduce pressure loss in curved flow channels

All's well that begins Wells: Celebrating 60 years of Animal Behaviour and 36 years of research on anuran social behaviour

The scientific study of frogs and toads as important systems in behavioural ecology traces its roots to an influential review published in this journal 36 years ago (Wells 1977a, ‘The social behaviour of anuran amphibians’, Animal Behaviour, 25, 666–693). In just 28 pages, Wells summarized the state of knowledge on important behaviours associated with anuran breeding and introduced an evolutionary framework ‘for understanding the relationship between social behaviour and ecology’ (page 666) that was largely lacking in earlier treatments of this group. Not only is Wells's review one of the most cited papers ever published in Animal Behaviour, it is also responsible for setting broad research agendas and shaping much of our current thinking on social behaviour in an entire order of vertebrates. As such, it is entirely appropriate that we honour Wells's review and its contributions to the study of animal behaviour in this inaugural essay celebrating 12 papers selected by the community as the most influential papers published in the 60-year history of Animal Behaviour. In our essay, we place Wells's review in historical context at the dawn of behavioural ecology, highlight the field's progress in answering some major research questions outlined in the review, and provide our own prospectus for future research on the social behaviour of anuran amphibians. Highlights ► This essay celebrates Kent Wells's (1977, Animal Behaviour, 25, 666–693) paper, ‘The social behaviour of anuran amphibians’. ► We place the article in historical context and outline its major contributions. ► We discuss progress on anuran social behaviour since its publication in 1977. ► We provide our own prospectus on the future of anuran behavioural ecology

Reexamination of Early Lunar Chronology With GRAIL Data: Terranes, Basins, and Impact Fluxes

Flooding of the lunar surface by ancient mare basalts has rendered uncertain the ages of lunar geochemical terranes and several impact basins. Here we combine craters having recognizable surface expressions with craters identified only by their gravitational signatures in Gravity Recovery and Interior Laboratory data to reassess the chronological sequence of lunar impact basins and the ages of major lunar geochemical terranes. Our results indicate that although volcanically flooded regions are deficient in craters with diameters greater than 20 km by more than 50% relative to unflooded regions, craters with diameters greater than 90 km can be readily recognized either by topography or by gravity anomaly. On the basis of the areal density of craters with diameters greater than 90 km we conclude that (1) the Serenitatis basin could be as young as the Imbrium basin; (2) the areal density of craters within the Procellarum KREEP Terrane is significantly lower than that for the South Pole‐Aitken basin and the Feldspathic Highlands Terrane; (3) if the youngest age of final crystallization of the lunar magma ocean is adopted as a lower bound on the age of the Procellarum KREEP Terrane, a minimum age of approximately 4.3 Ga is inferred for ~40% of lunar impact basins, including South Pole‐Aitken; and (4) the flux of impactors capable of forming craters with diameters of at least 90 km decreased substantially through the Nectarian and Imbrian periods

Combined finite element and peridynamic analyses for predicting failure in a stiffened composite curved panel with a central slot

This study presents an analysis approach based on a merger of the finite element method and the peridynamic theory. Its validity is established through qualitative and quantitative comparisons against the test results for a stiffened composite curved panel with a central slot under combined internal pressure and axial tension. The predicted initial and final failure loads, as well as the final failure modes, are in close agreement with the experimental observations. This approach demonstrates the capability of the PD approach to assess the durability of complex composite structures

Contribution à l'étude des acides β-(naphtoyl) et β-(2-tétroyl)-acryliques

Nous avons préparé et confirmé la structure des acides β‐(l‐naphtoyl)(I), β‐(2‐naphtoyl)(IIα) et β‐(2‐tétroyl)‐acryliques (IIb). Nous avons montré que le dérivé précédemment décrit comme acide β‐(2‐naphtoyl)‐acrylique est probablement un isomère cyclique saturé de l'acide β‐(l‐naphtoyl)‐acrylique. La réaction de Friedel‐Crafts entre la tétraline et l'anhydride maléïque fournit suivant les conditions expérimentales soit l'acide β‐(2‐tétroyl)‐propionique soit l'acide β‐(2‐tétroyl)‐acrylique. Copyright © 1950 Wiley‐VCH Verlag GmbH & Co. KGaA, WeinheimSCOPUS: ar.jinfo:eu-repo/semantics/publishe