Social Media for Cities, Counties and Communities

Social media (i.e., Twitter, Facebook, Flickr, YouTube) and other tools and services with user- generated content have made a staggering amount of information (and misinformation) available. Some government officials seek to leverage these resources to improve services and communication with citizens, especially during crises and emergencies. Yet, the sheer volume of social data streams generates substantial noise that must be filtered. Potential exists to rapidly identify issues of concern for emergency management by detecting meaningful patterns or trends in the stream of messages and information flow. Similarly, monitoring these patterns and themes over time could provide officials with insights into the perceptions and mood of the community that cannot be collected through traditional methods (e.g., phone or mail surveys) due to their substantive costs, especially in light of reduced and shrinking budgets of governments at all levels. We conducted a pilot study in 2010 with government officials in Arlington, Virginia (and to a lesser extent representatives of groups from Alexandria and Fairfax, Virginia) with a view to contributing to a general understanding of the use of social media by government officials as well as community organizations, businesses and the public. We were especially interested in gaining greater insight into social media use in crisis situations (whether severe or fairly routine crises, such as traffic or weather disruptions)

Flight Services and Aircraft Access: Active Flow Control Vertical Tail and Insect Accretion and Mitigation Flight Test

This document serves as the final report for the Flight Services and Aircraft Access task order NNL14AA57T as part of NASA Environmentally Responsible Aviation (ERA) Project ITD12A+. It includes descriptions of flight test preparations and execution for the Active Flow Control (AFC) Vertical Tail and Insect Accretion and Mitigation (IAM) experiments conducted on the 757 ecoDemonstrator. For the AFC Vertical Tail, this is the culmination of efforts under two task orders. The task order was managed by Boeing Research & Technology and executed by an enterprise-wide Boeing team that included Boeing Research & Technology, Boeing Commercial Airplanes, Boeing Defense and Space and Boeing Test and Evaluation. Boeing BR&T in St. Louis was responsible for overall Boeing project management and coordination with NASA. The 757 flight test asset was provided and managed by the BCA ecoDemonstrator Program, in partnership with Stifel Aircraft Leasing and the TUI Group. With this report, all of the required deliverables related to management of this task order have been met and delivered to NASA as summarized in Table 1. In addition, this task order is part of a broader collaboration between NASA and Boeing

Aerodynamic Simulation of Runback Ice Accretion

This report presents the results of recent investigations into the aerodynamics of simulated runback ice accretion on airfoils. Aerodynamic tests were performed on a full-scale model using a high-fidelity, ice-casting simulation at near-flight Reynolds (Re) number. The ice-casting simulation was attached to the leading edge of a 72-in. (1828.8-mm ) chord NACA 23012 airfoil model. Aerodynamic performance tests were conducted at the ONERA F1 pressurized wind tunnel over a Reynolds number range of 4.7?10(exp 6) to 16.0?10(exp 6) and a Mach (M) number ran ge of 0.10 to 0.28. For Re = 16.0?10(exp 6) and M = 0.20, the simulated runback ice accretion on the airfoil decreased the maximum lift coe fficient from 1.82 to 1.51 and decreased the stalling angle of attack from 18.1deg to 15.0deg. The pitching-moment slope was also increased and the drag coefficient was increased by more than a factor of two. In general, the performance effects were insensitive to Reynolds numb er and Mach number changes over the range tested. Follow-on, subscale aerodynamic tests were conducted on a quarter-scale NACA 23012 model (18-in. (457.2-mm) chord) at Re = 1.8?10(exp 6) and M = 0.18, using low-fidelity, geometrically scaled simulations of the full-scale castin g. It was found that simple, two-dimensional simulations of the upper- and lower-surface runback ridges provided the best representation of the full-scale, high Reynolds number iced-airfoil aerodynamics, whereas higher-fidelity simulations resulted in larger performance degrada tions. The experimental results were used to define a new subclassification of spanwise ridge ice that distinguishes between short and tall ridges. This subclassification is based upon the flow field and resulting aerodynamic characteristics, regardless of the physical size of the ridge and the ice-accretion mechanism

Location matters: evaluating Greater Prairie-Chicken (Tympanuchus cupido) boom chorus propagation

Anthropogenic disturbances can affect species of conservation concern by influencing their behavior. Of special concern is the possibility that noise from anthropogenic structures in grassland habitats, such as wind turbines and roads, may affect the propagation of the low-frequency boom chorus of lekking male Greater Prairie-Chickens (Tympanuchus cupido). We used sound pressure levels from acoustic recordings taken at 10 leks in the Nebraska Sandhills, USA during 2013 and 2014 in a SPreAD-GIS sound propagation model to make spatial projections of the boom chorus under a variety of conditions including landscape composition, conspecific attendance, and weather. We then used sets of linear mixed models in a model selection process to determine how background noise, female and male lek attendance, time of day, relative humidity, air temperature, and wind speed affected the area of chorus propagation. The predicted area of propagation decreased with increasing background noise (β = -0.09, SE = 0.04) and increased with greater female lek attendance (β = 0.09, SE = 0.03), higher levels of relatively humidity (β = 0.07, SE = 0.03), and higher air temperatures (β = 0.05, SE = 0.03). Our analyses provide new insight on how acoustic, social, and meteorological factors influence an important reproductive behavior in an imperiled prairie grouse

Optimal deadrise hull analysis and design space study of naval special warfare high speed planning boats

Thesis (S.M. in Naval Architecture and Marine Engineering)--Massachusetts Institute of Technology, Dept. of Ocean Engineering; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2002.Includes bibliographical references (leaves 64-65).United States Navy SEALs (Sea, Air, Land) frequently employ high speed planing boats (HSPBs) in the performance of their missions. Operation of these vessels in normal and adverse conditions exposes personnel to severe mechanical shock. Anecdotal evidence and recent medical studies conducted by the Naval Health Research Center show a correlation between HSPB operation and chronic and acute personnel injury. Most current research focuses on short-term solutions that reduce shock at the hull-deck and deck-seat interfaces (deck padding and suspension seats, for example). The object of this thesis is to develop an Optimal Deadrise Hull (ODH) that reduces mechanical shock where it first enters the boat, at the hull-sea interface. Planing boat hydrodynamics were reviewed and the mechanical shock environment was evaluated. The ODH analysis is performed on the MkV Special Operations Craft in order to determine the effects of hull deadrise on vertical acceleration. Finally, the results of the ODH analysis are used to perform a design space study of planing hulls in order to optimize the overall design for vertical acceleration based on hull deadrise, cruise speed, and payload weight.by Todd E. Whalen.S.M.S.M.in Naval Architecture and Marine Engineerin

AFC-Enabled Vertical Tail System Integration Study

This document serves as the final report for the SMAAART AFC-Enabled Vertical Tail System Integration Study. Included are the ground rule assumptions which have gone into the study, layouts of the baseline and AFC-enabled configurations, critical sizing information, system requirements and architectures, and assumed system properties that result in an NPV assessment of the two candidate AFC technologies

Acoustic Characteristics of Lekking Male Greater Prairie-Chicken (\u3ci\u3eTympanuchus cupido pinnatus\u3c/i\u3e) Vocalizations (Supplement)

Boom Cackle Whine Whoo

Lift Recovery for AFC-Enabled High Lift System

This project is a continuation of the NASA AFC-Enabled Simplified High-Lift System Integration Study contract (NNL10AA05B) performed by Boeing under the Fixed Wing Project. This task is motivated by the simplified high-lift system, which is advantageous due to the simpler mechanical system, reduced actuation power and lower maintenance costs. Additionally, the removal of the flap track fairings associated with conventional high-lift systems renders a more efficient aerodynamic configuration. Potentially, these benefits translate to a approx. 2.25% net reduction in fuel burn for a twin-engine, long-range airplane

Technique for Enhanced Flow Control Efficiency Through Thermal Actuation

Thermal active flow control has been developed to enhance the efficiency of active flow control systems. The actuation concept is derived from gas-dynamics principles, and it is based on thermal control of the air supply. It is shown that higher air supply temperatures result in reduced mass flow rate with no degradation in active flow control performance. A computational method has been used to systematically investigate the hot air supply approach for isolated blowing actuators and fluidic oscillators. Subsequently, the thermal control concept has been computationally evaluated for airplane applications. These include enhanced control authority of a vertical tail and an airplane high-lift system, confirming the trends observed from the gas-dynamics analysis with regard to reduced actuation input as a function of supply temperature. Further confirmation of the thermal actuation concept was experimentally obtained for a bench-top actuator and a vertical-tail model in a wind-tunnel setting. The paper introduces potential approaches for system integration associated with heated supply, while highlighting the benefit of using available high-temperature sources for active flow control