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A data-stream classification system for investigating terrorist threats

Published in:
Proc. SPIE 9851, Next-Generation Analyst IV, 98510L (May 12, 2016); doi:10.1117/12.2224104.

Summary

The role of cyber forensics in criminal investigations has greatly increased in recent years due to the wealth of data that is collected and available to investigators. Physical forensics has also experienced a data volume and fidelity revolution due to advances in methods for DNA and trace evidence analysis. Key to extracting insight is the ability to correlate across multi-modal data, which depends critically on identifying a touch-point connecting the separate data streams. Separate data sources may be connected because they refer to the same individual, entity or event. In this paper we present a data source classification system tailored to facilitate the investigation of potential terrorist activity. This taxonomy is structured to illuminate the defining characteristics of a particular terrorist effort and designed to guide reporting to decision makers that is complete, concise, and evidence-based. The classification system has been validated and empirically utilized in the forensic analysis of a simulated terrorist activity. Next-generation analysts can use this schema to label and correlate across existing data streams, assess which critical information may be missing from the data, and identify options for collecting additional data streams to fill information gaps.
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Summary

The role of cyber forensics in criminal investigations has greatly increased in recent years due to the wealth of data that is collected and available to investigators. Physical forensics has also experienced a data volume and fidelity revolution due to advances in methods for DNA and trace evidence analysis. Key...

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Development and use of a comprehensive humanitarian assessment tool in post-earthquake Haiti

Summary

This paper describes a comprehensive humanitarian assessment tool designed and used following the January 2010 Haiti earthquake. The tool was developed under Joint Task Force -- Haiti coordination using indicators of humanitarian needs to support decision making by the United States Government, agencies of the United Nations, and various non-governmental organizations. A set of questions and data collection methodology were developed by a collaborative process involving a broad segment of the Haiti humanitarian relief community and used to conduct surveys in internally displaced person settlements and surrounding communities for a four-month period starting on 15 March 2010. Key considerations in the development of the assessment tool and data collection methodology, representative analysis results, and observations from the operational use of the tool for decision making are reported. The paper concludes with lessons learned and recommendations for design and use of similar tools in the future.
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Summary

This paper describes a comprehensive humanitarian assessment tool designed and used following the January 2010 Haiti earthquake. The tool was developed under Joint Task Force -- Haiti coordination using indicators of humanitarian needs to support decision making by the United States Government, agencies of the United Nations, and various non-governmental...

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Multifunction Phased Array Radar (MPAR): achieving Next Generation Surveillance and Weather Radar Capability

Published in:
J. Air Traffic Control, Vol. 55, No. 3, Fall 2013, pp. 40-7.

Summary

Within DOT, the FAA has initiated an effort known as the NextGen Surveillance and Weather Radar Capability (NSWRC) to analyze the need for the next generation radar replacement and assess viable implementation alternatives. One concept under analysis is multifunction radar using phased-array technology -- Multifunction Phased Array Radar or MPAR.
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Summary

Within DOT, the FAA has initiated an effort known as the NextGen Surveillance and Weather Radar Capability (NSWRC) to analyze the need for the next generation radar replacement and assess viable implementation alternatives. One concept under analysis is multifunction radar using phased-array technology -- Multifunction Phased Array Radar or MPAR.

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Measurement of aerosol-particle trajectories using a structured laser beam

Summary

What is believed to be a new concept for the measurement of micrometer-sized particle trajectories in an inlet air stream is introduced. The technique uses a light source and a mask to generate a spatial pattern of light within a volume in space. Particles traverse the illumination volume and elastically scatter light to a photodetector where the signal is recorded in time. The detected scattering waveform is decoded to find the particle trajectory. A design is presented for the structured laser beam, and the accuracy of the technique in determining particle position is demonstrated. It is also demonstrated that the structured laser beam can be used to measure and then correct for the spatially dependent instrument-response function of an optical-scattering-based particle-sizing system for aerosols.
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Summary

What is believed to be a new concept for the measurement of micrometer-sized particle trajectories in an inlet air stream is introduced. The technique uses a light source and a mask to generate a spatial pattern of light within a volume in space. Particles traverse the illumination volume and elastically...

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An assessment of automated boundary and front detection to support convective initiation forecasts

Summary

One of the largest sources of error in the current automated convective weather forecast systems is due to its inability to accurately account for new convective storm development. In many situations the initiation of new convection is preceded by low altitude convergence in the horizontal winds. These regions of low altitude convergence, often referred to as boundaries, are typically associated with synoptic scale fronts, drylines, and thunderstorm outflows. Gridded wind analyses that utilize Doppler weather radar, surface, and aircraft measurements are one of the best sources of low altitude winds that can be used to identify wind boundaries over large domains. This study summarizes the preliminary results of a study which examined the feasibility of using gridded wind analyses from operational wind analysis systems to make automated detections of wind boundaries. The analysis focused on two operational wind analysis systems both capable of producing high update, and high spatial resolution wind analyses over a domain that covers the eastern half of the Continental United Sates (CONUS), the Space Time Mesoscale Analysis System (STMAS) and the Corridor Boundary layer wind analysis system (CBOUND). Wind analyses from both systems were first processed with a Lagrangian temporal filter and then passed through an automated boundary detection algorithm based on the Terminal Doppler Weather Radar (TDWR) Machine Intelligent Gust Front Algorithm (MIGFA). The results indicate that the temporal filter improves the boundary signal to noise ratio such that it is technically feasible to make fully automated boundary detections with image processing techniques.
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Summary

One of the largest sources of error in the current automated convective weather forecast systems is due to its inability to accurately account for new convective storm development. In many situations the initiation of new convection is preceded by low altitude convergence in the horizontal winds. These regions of low...

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Nowcasting requirements for the aircraft vortex spacing system (AVOSS)

Published in:
8th Conf. on Aviation, Range, and Aerospace Meteorology, 10-15 Jan. 1999, pp. 340-344.

Summary

Aircraft wake vortices are counter-rotating tubes of air that are generated from aircraft as a consequence of the lift on the aircraft. The safety concern of wake vortices, particularly when lighter aircraft are following heavy planes, has caused the Federal Aviation Administration (FAA) to enact minimum separation requirements during the arrival phase of flight. These separation standards are imposed at the arrival threshold during Instrument Flight Rules (IFR) and are a significant constraint on arrival capacity at the largest U.S. airports. Any movement toward increasing air traffic efficiency, such as concepts toward free-flight, must address increasing runway capacity if they are to be fully effective. Decades of past wake vortex measurements clearly show that current wake vortex separations are overconservative in many weather conditions, and that adapting the separations to the current weather state could safely reduce these separations...This paper describes the known meteorological influences on vortex behavior and gives an overview of AVOSS. Airport climatology is studied to discuss the prevalence of conditions that are conducive to capacity increases with AVOSS technology. Finally, additional constraints on AVOSS nowcasts are discussed.
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Summary

Aircraft wake vortices are counter-rotating tubes of air that are generated from aircraft as a consequence of the lift on the aircraft. The safety concern of wake vortices, particularly when lighter aircraft are following heavy planes, has caused the Federal Aviation Administration (FAA) to enact minimum separation requirements during the...

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Range obscuration mitigation by adaptive PRF selection for the TDWR System

Published in:
24th Conf. on Radar Meteorology, 27-31 March 1989, pp. 175-178.

Summary

The Federal Aviation Administration has recently awarded a contract for the procurement of 47 Terminal Doppler Weather Radar (TDWR) systems to be sited near high traffic airports. These systems will collect and process Doppler radar data that will be used by fully automated algorithms to identify hazardous meteorological wind shear events in real time (eg., microbursts and gust fronts.) This information will the be conveyed to aircraft pilots in order that potentially hazardous takeoffs or landings be averted. In a pulsed Doppler weather radar, one of the most serious causes of data quality degradation is due to range aliased echoes from distant storms [3]. This range contamination can occur in the immediate vicinity of a meteorological hazard, possibly obscure the event, and thus decrease the probability of detecting it. In other instances, range contaminated data can present a radar signature similar to that of a wind shear hazard, and perhaps cause an algorithm to issue a false alarm. In order for the TDWR system to achieve a high probability of detecting meteorological hazards, while maintaining a low probability of false alarms, an effective means of dealing with range contamination is required. An adaptive procedure by which to select the radar's pulse repetition frequency (Pm) has been developed as a primary means by which to minimize range contamination within the operationally significant coverage area of a TDWR system. This procedure will be developed within this paper and a quantitative assessment as to the anticipated effectiveness of this technique in the TDWR system will be provided.
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Summary

The Federal Aviation Administration has recently awarded a contract for the procurement of 47 Terminal Doppler Weather Radar (TDWR) systems to be sited near high traffic airports. These systems will collect and process Doppler radar data that will be used by fully automated algorithms to identify hazardous meteorological wind shear...

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Evaluation of the ASR-9 weather reflectivity product

Author:
Published in:
Proc. Second Int. Conf. on the Aviation Weather System, 19-21 June 1985, pp. 196-202.

Summary

The ASR-9 is a modern airport surveillance radar (ASR) under procurement by the United States Federal Aviation Agency. The radar operates at S-band, providing range-azimuth position information on aircraft targets within a 111-km radius. A fully-coherent klystron amplifier, large dynamic range and digital signal processing enable high integrity target processing and display under condition of ground clutter, weather, angel clutter, RF interference and ground vehicular traffic. To aid controllers in the identification of hazardous weather conditions, the processor will also generate two- or six-level weather reflectivity contours for display at the terminal radar control center and (potentially) remote sites. In this paper, we present an overview of the ASR-9 and its weather processor, emphasizing those features that raise issues with respect to the utility of the weather reflectivity product in an air-traffic control environment. We then describe a simulation procedure that utilizes pencil-beam Doppler weather radar data and ground clutter measurements to preview the ASR-9 product and assess the effects of the radar's configuration on the weather intensity reports. Examples of the simulated weather reports are used to illustrate" (a) partial beamfilling die to the fan-shaped surveillance antenna pattern; (b) attenuation of low velocity weather by the clutter filters' (c) the effects of the spatial filters used in weather processing.
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Summary

The ASR-9 is a modern airport surveillance radar (ASR) under procurement by the United States Federal Aviation Agency. The radar operates at S-band, providing range-azimuth position information on aircraft targets within a 111-km radius. A fully-coherent klystron amplifier, large dynamic range and digital signal processing enable high integrity target processing...

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The FAA/MIT Lincoln Laboratory Doppler Weather Radar Program

Published in:
Proc. Second Int. Conf. on the Aviation Weather Systems, 19-21 June 1985, pp. 76-79.

Summary

Adverse weather is the leading cause of aircraft accidents in the United States. In order to improve hazardous weather detection and warning capability for aviation, the Federal Aviation Administration (FAA) is pursuing a two part Doppler weather radar program. The first part consists of a joint program with the National Weather Service (NWS) and United States Air Force Weather Service (AWS) is to develop and install the Next Generation Weather Radar (NEXRAD). The NEXRAD Systems will meet the FAA enroutw hazardous weather detection requirements and will replace the existing obsolete NWS and AWS weather radars. The second part of the FAA program is the development of a Terminal Doppler Weather Radar (TDWR), which could be procured and installed at major airports to detect weather hazards to terminal aviation operations. The TDWR couls be either a derivative of NEXRAD or a separate radar system. In order to support both of these efforts, the FAA contracted with M.I.T. Lincoln Laboratory to develop and fabricate a NEXRAD-like transportable weather radar support facility. This facility along with a second Doppler radar and a network of meteorological measurement stations are installed near Memphis, Tennessee. These facilities will be used to validate and refine scanning strategies, data processing techniques, and weather detection algorithms. The utility of weather radar products for air traffic control (especially for pilots and controllers) will be evaluated.
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Summary

Adverse weather is the leading cause of aircraft accidents in the United States. In order to improve hazardous weather detection and warning capability for aviation, the Federal Aviation Administration (FAA) is pursuing a two part Doppler weather radar program. The first part consists of a joint program with the National...

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A high stability TWTA for ground surveillance applications

Published in:
Proc. 1984 IEEE Natl. Radar Conf., 13-14 March 1984, pp. 110-114.

Summary

A high stability, C-band transmitter capable of supporting -68 dBr subclutter visibility over a wide range of pulse widths and duty factors was developed for use in a multimode, battlefield surveillance radar. The transmitter was mode-switched between groups of 1/4, 20 and 65 microsecond radar pulses and long duration (100ms) FSK burst. A key feature was the use of a high speed, interpulse regulator to maintain proper TWT voltage and to limit ripple independent of waveform without the need for excessively large energy storage. Actual measured performance met the 100 mV cathode ripple specification without the use of PKF synchronization, independent of PKI, duty cycle and pulse width and was confirmed via direct evaluation of electrode voltages, serrodyne phase jitter and the radar pulsed-Doppler spectrum.
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Summary

A high stability, C-band transmitter capable of supporting -68 dBr subclutter visibility over a wide range of pulse widths and duty factors was developed for use in a multimode, battlefield surveillance radar. The transmitter was mode-switched between groups of 1/4, 20 and 65 microsecond radar pulses and long duration (100ms)...

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