8,871 research outputs found

    A Neoselachian shark from the non-marine Wessex Formation (Wealden Group: early Cretaceous, Barremian) of the Isle of Wight, southern England

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    Bulk screening of Early Cretaceous (Barremian) Wessex Formation strata exposed on the south-east coast of the Isle of Wight, southern England, has resulted in the recovery of neoselachian shark teeth referred to the scyliorhinid Palaeoscyllium. These are the first neoselachian remains from the British Wealden Group and represent the geologically oldest neoselachian yet recovered from a freshwater deposit. This is also the only known example of a non-marine occurrence of a member of the Scyliorhinidae

    The development of aerodynamic uncertainties for the space shuttle orbiter

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    The Shuttle Program development schedule and the management decision to perform an orbital, manned mission on the first launch resulted in a requirement to develop realistic aerodynamic uncertainties for the preflight aerodynamic predictions. This paper addresses the methodology in developing two types of aerodynamic uncertainties. One involves the ability to reproduce aerodynamic results between various wind tunnel tests. The second addresses the difference between preflight aerodynamic predictions and flight results derived from analysis of past aircraft programs. Both types of uncertainties for pitching moment, lateral-directional stability, rudder power, and aileron power are presented. In addition, the application of uncertainties to flight control design and fight test planning is briefly reviewed

    Understanding Extended Projected Profile (EPP) Trajectory Error Using a Medium-Fidelity Aircraft Simulation

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    A critical component of Trajectory-Based Operations is the ability for a consistent and accurate 4-dimensional trajectory to be shared and synchronized between airborne and ground systems as well as amongst various ground automation systems. The Aeronautical Telecommunication NetworkBaseline 2 standard defines the Extended Projected Profile (EPP) trajectory that can be sent via Automatic Dependent Surveillance-Contract from an aircraft to ground automation. The EPP trajectory message contains a representation of the reference trajectory from an aircrafts Flight Management System (FMS). In this work, a set of scenarios were run in a medium-fidelity aircraft and FMS simulation to perform an initial characterization of EPP trajectory errors under a given set of conditions. The parameters investigated were the route length, route type, wind magnitude error, wind direction error, and with and without a required time-of-arrival constraint

    Cladding strategies for building-integrated photovoltaics

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    Photovoltaic cladding on the surfaces of commercial buildings has the potential for considerable reductions in carbon emissions due to embedded renewable power generation displacing conventional power utilization. In this paper, a model is described for the optimization of photovoltaic cladding densities on commercial building surfaces. The model uses a modified form of the ‘fill factor’ method for photovoltaic power supply coupled to new regression-based procedures for power demand estimation. An optimization is included based on a defined ‘mean index of satisfaction’ for matched power supply and demand (i.e., zero power exportation to the grid). The mean index of satisfaction directly translates to the reduction in carbon emission that might be expected over conventional power use. On clear days throughout the year, reductions of conventional power use of at least 60% can be achieved with an optimum cladding pattern targeted to lighting and small power load demands

    Exercise and progressive supranuclear palsy : the need for explicit exercise reporting

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    Background Progressive Supranuclear Palsy (PSP) is the most frequent form of atypical Parkinsonism. Although there is preliminary evidence for the benefits of gait rehabilitation, balance training and oculomotor exercises in PSP, the quality of reporting of exercise therapies appears mixed. The current investigation aims to evaluate the comprehensiveness of reporting of exercise and physical activity interventions in the PSP literature. Methods Two independent reviewers used the Consensus on Exercise Reporting Template (CERT) to extract all exercise intervention data from 11 studies included in a systematic review. CERT items covered: ‘what’ (materials), ‘who’ (instructor qualifications), ‘how’ (delivery), ‘where’ (location), ‘when’, ‘how much’ (dosage), ‘tailoring’ (what, how), and ‘how well’ (fidelity) exercise delivery complied with the protocol. Each exercise item was scored ‘1’ (adequately reported) or ‘0’ (not adequately reported or unclear). The CERT score was calculated, as well as the percentage of studies that reported each CERT item. Results The CERT scores ranged from 3 to 12 out of 19. No PSP studies adequately described exercise elements that would allow exact replication of the interventions. Well-described items included exercise equipment, exercise settings, exercise therapy scheduling, frequency and duration. Poorly described items included decision rules for exercise progression, instructor qualifications, exercise adherence, motivation strategies, safety and adverse events associated with exercise therapies. Discussion The results revealed variability in the reporting of physical therapies for people living with PSP. Future exercise trials need to more comprehensively describe equipment, instructor qualifications, exercise and physical activity type, dosage, setting, individual tailoring of exercises, supervision, adherence, motivation strategies, progression decisions, safety and adverse events. Conclusion Although beneficial for people living with PSP, exercise and physical therapy interventions have been inadequately reported. It is recommended that evidence-based reporting templates be utilised to comprehensively document therapeutic exercise design, delivery and evaluation

    An open framework for highly concurrent hardware-in-the-loop simulation

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    Hardware-in-the-loop (HIL) simulation is becoming a significant tool in prototyping complex, highly available systems. The HIL approach allows an engineer to build a physical system incrementally by enabling real components of the system to seamlessly interface with simulated components. It also permits testing of hardware prototypes of components that would be extremely costly to test in the deployed environment. Key issues are the ability to wrap the systems of equations (such as Partial Differential Equations) describing the deployed environment into real-time software models, provide low synchronization overhead between the hardware and software, and reduce reliance on proprietary platforms. This thesis introduces an open source HIL simulation framework that can be ported to any standard Unix-like system on any shared-memory multiprocessor computer, requires minimal operating system scheduler controls, provides a soft real-time guarantee for any constituent simulation that does likewise, enables an asynchronous user interface, and allows for an arbitrary number of secondary control components --Abstract, page iii

    Illinois Judicial System

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    * Lindenwood Millinery Show (March 1927)

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    An article about the Lindenwood College Millinery Show (March 1927)

    A MEMS Dual Vertical Electrometer and Electric Field-Mill

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    Presented is the first iteration of a Microelectromechanical System (MEMS) dual vertical electrometer and electric field-mill (EFM). The device uses a resonating structure as a variable capacitor that converts the presence of a charge or field into an electric signal. Previous MEMS electrometers are lateral electrometers with laterally spaced electrodes that resonate tangentially with respect to each other. Vertical electrometers, as the name suggests, have vertically spaced electrodes that resonate transversely with respect to each other. The non-tangential movement reduces damping in the system. Both types demonstrate comparable performance, but the vertical electrometer does so at a fraction of the size. In addition, vertical electrometers can efficiently operate as an electric field sensor. The electric field sensor simulations did not compare as well to other MEMS electric field sensors. However, the dual nature of this device makes it appealing. These devices can be used in missiles and satellites to monitor charge buildup in electronic components and the atmosphere [11]. Future iterations can improve these devices and give way to inexpensive, high-resolution electrostatic charge and field sensors

    Illinois Judicial System

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