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Crowdsourcing has been widely leveraged for the tagging of video material; recently this has included the monitoring of surveillance video footage. However, the relative advantages and disadvantages of crowdsourcing watchers of su...
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Crowdsourcing has been widely leveraged for the tagging of video material; recently this has included the monitoring of surveillance video footage. However, the relative advantages and disadvantages of crowdsourcing watchers of surveillance video are not well articulated, nor has there been any significant work on the efficacy of different tools for retrospective surveillance. In this paper we explore factors that might affect crowd performance on video surveillance monitoring tasks. We firstly established a baseline for crowd performance in a 'live' surveillance study before comparing two different interfaces that allowed retrospective discovery of the same events (Scrub Player and Panopticon). Using MTurk, we asked 474 people to monitor two types of CCTV footage containing different levels of extraneous activity for 'events' using these two interfaces. We also manipulated bonus payments. We found that the crowd was most accurate when watching the video that contained the least extraneous activity, that there was no effect of financial incentive on the reporting of true events, but that there was some indication that higher bonus payments generated more false alarms. We also found an effect of interface: those using the Panopticon interface processed more video footage and generated more alerts, but were less accurate overall. We discuss the implications of different interface designs, video types, and incentive schemes when crowdsourcing watchers of surveillance video.
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NASA’s Goddard Space Flight Center (GSFC) is working on maturing the technology readiness of a laser transmitter designed for use in atmospheric CO2 remote-sensing. GSFC has been developing an airplane-based CO2 lidar instrument ...
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NASA’s Goddard Space Flight Center (GSFC) is working on maturing the technology readiness of a laser transmitter designed for use in atmospheric CO2 remote-sensing. GSFC has been developing an airplane-based CO2 lidar instrument over several years to demonstrate the efficacy of the instrumentation and measurement technique and to link the science models to the instrument performance. The ultimate goal is to make space-based satellite measurements with global coverage. In order to accomplish this, we must demonstrate the technology readiness and performance of the components as well as demonstrate the required power-scaling to make the link with the required signal-to-noise-ratio (SNR). To date, all the instrument components have been shown to have the required performance with the exception of the laser transmitter.In this program we are working on a fiber-based master oscillator power amplifier (MOPA) laser transmitter architecture where we will develop a ruggedized package and perform the relevant environmental tests to demonstrate TRL-6. In this paper we will review our transmitter architecture and progress on the performance and packaging of the laser transmitter.
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We have demonstrated a low-noise heterodyne three-element focal plane array (FPA) at 1.6 THz consisting of NbN Hot Electron Bolometric (HEB) detectors, intimately integrated with monolithic microwave integrated circuit (MMIC) IF a...
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We have demonstrated a low-noise heterodyne three-element focal plane array (FPA) at 1.6 THz consisting of NbN Hot Electron Bolometric (HEB) detectors, intimately integrated with monolithic microwave integrated circuit (MMIC) IF amplifiers in a single block. HEB technology is becoming the basis for advanced terahertz imaging and spectroscopic technologies for the study of biological and chemical agents over the entire terahertz spectrum. The use of FPAs is crucial for maximizing the detection speed in these applications.
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Utilizing a unique, Far West Technology Tissue Equivalent Proportional Counter (TEPC)-based system called the HAWK, the atmospheric radiation exposures of commercial air travelers and naval personnel were compared to the quantity ...
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Utilizing a unique, Far West Technology Tissue Equivalent Proportional Counter (TEPC)-based system called the HAWK, the atmospheric radiation exposures of commercial air travelers and naval personnel were compared to the quantity predicted by commercially available radiation codes. The HAWK simulates a two micron-diameter somatic cell, measuring the lineal energy, absorbed dose, and dose equivalent based on the International Commission on Radiological Protection (ICRP)-60 recommendations. Prior to the flights, the HAWK detector response was modeled with MCNP5 and GEANT4. Later, the data were analyzed both to produce a dose rate as well as a total dose for the flight's duration. Over 40 hours of flight data was obtained on commercial aircraft in addition to several experiments on military and private aircraft. Flights were conducted across the continental United States, from Massachusetts to California. The military flights were conducted on an EA-6B Prowler from the Navy's VX-23 Squadron in Patuxent River, Maryland. Commercial aircraft altitudes reached a ceiling of approximately 38,000 feet while typical military operations were around 25,000 feet. During the flight, data including dose and dose equivalent rates were collected along with corresponding GPS data such as geodetic latitude, longitude, and altitude. The GPS data were then utilized as inputs for several commercially available radiation codes for assessing atmospheric radiation risk.
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In this paper, the control problem of utilizing a team of autonomous marine vehicles (i.e., tug boats) cooperating to manipulate a larger floating object (i.e. disabled ship) while operating in a decentralized architecture is cons...
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In this paper, the control problem of utilizing a team of autonomous marine vehicles (i.e., tug boats) cooperating to manipulate a larger floating object (i.e. disabled ship) while operating in a decentralized architecture is considered. After decomposing the problem into several phases, a control design targeting the issue of inducing controlled rotations for the manipulated object is presented.
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This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). We conducted studies of the propagation of self-confined packets of light or 'Opti...
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This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). We conducted studies of the propagation of self-confined packets of light or 'Optical Bullets' through air. These packets are self-forming and require no active optics. At the present time, theoretical explanations provide an incomplete description of this process. Generation of these pulses requires a light source of sufficient energy and with a short enough pulse-width that the intensity exceeds a critical wavelength dependent value. We used a Ti:Sapphire based system to generate the pulses and we observed pulse-splitting and chirp-dependent control of the formation of these filaments. In addition, we developed a novel algorithm for extracting the phase and electric field of these pulses using Frequency Resolved Optical Gating coupled to genetic algorithms for pulse retrieval.
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This work performed over this twenty-eight month contract period falls into two categories: studies of fluid plasma and transport properties (specifically, microturbulent resistivity) in opening switch plasmas in support of the SN...
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This work performed over this twenty-eight month contract period falls into two categories: studies of fluid plasma and transport properties (specifically, microturbulent resistivity) in opening switch plasmas in support of the SNLA PBFA-II pulsed power program; and calculations of two-dimensional effects in gas puff plasmas in support of the SNLA NARYA program. Results of this work are reported here. 34 refs., 30 figs.
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The scope of this book is to show the potential energy savings through lowering of cooker temperature and through various redesigns, such as vapor recycle, water recycle, steam locks, insulation, etc. and in a comprehensive form p...
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The scope of this book is to show the potential energy savings through lowering of cooker temperature and through various redesigns, such as vapor recycle, water recycle, steam locks, insulation, etc. and in a comprehensive form provide a procedure for the Food Processor to determine the individual savings potential and to select the most efficient mode of operation. There have been selected and discussed various tests which hopefully together with the more general theoretical background will aid the Food Processor in obtaining a more efficient atmospheric cooker operation. (ERA citation 09:012262)
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