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Cognitive workload and visual attention analyses of the air traffic control Tower Flight Data Manager (TFDM) prototype demonstration

Published in:
HFES 2012, Human Factors and Ergonomics Society 56th Annual Mtg., 22-26 October 2012.

Summary

This paper presents two methods of analyzing air traffic controller activity: cognitive workload measurement through the novel comparison of controller-pilot verbal communications, and visual attention quantification through manual eye gaze analysis. These analyses were performed as part of an evaluation of the Tower Flight Data Manager (TFDM) prototype system. Cognitive workload analyses revealed that, when comparing participant controllers utilizing TFDM to a control group utilizing existing air traffic control (ATC) equipment, participants issued commands sooner than the control, and thus were perceived to have a lower workload. While visual attention data were not available for the control group, analyses of participant gaze data revealed 81.9% of time was spent in a head-down position, and 17.2% of time was spent head-up. Results are related back to system inefficiencies to find potential areas of improvement in design.
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Summary

This paper presents two methods of analyzing air traffic controller activity: cognitive workload measurement through the novel comparison of controller-pilot verbal communications, and visual attention quantification through manual eye gaze analysis. These analyses were performed as part of an evaluation of the Tower Flight Data Manager (TFDM) prototype system. Cognitive...

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Estimating the monetizable safety benefits of prototype air traffic control technologies

Published in:
HFES 2012, Human Factors and Ergonomics Society 56th Annual Mtg., 22-26 October 2012.

Summary

The Federal Aviation Administration (FAA) utilizes a formal investment analysis process to support the development, procurement and deployment of new air traffic control technologies. It is often unclear how to estimate the impacts of a new technology on aviation safety, both in terms of the probability that incidents and accidents could be prevented and in terms of the potential financial savings associated with reduced aircraft damage and personal injuries. With this in mind, the focus of this paper is twofold: (1) demonstrating the application of a method for generating probabilistic estimates of safety benefits for a future air traffic control technology, and (2) monetizing and extrapolating safety impacts from historical data to provide a quantitative estimate of savings over the lifetime of a new technology. The technologies explored in this analysis involve electronic flight data, enhanced surveillance and decision support tools for the air traffic control tower environment. From this initial analysis, the estimated total monetizable safety benefit of deploying all of these capabilities in a new system with an expected 2015-2035 lifetime across a set of major airports in the US ranges from $155 million to $2.1 billion. Implications of key data assumptions driving the lower and upper-bound estimates are discussed.
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Summary

The Federal Aviation Administration (FAA) utilizes a formal investment analysis process to support the development, procurement and deployment of new air traffic control technologies. It is often unclear how to estimate the impacts of a new technology on aviation safety, both in terms of the probability that incidents and accidents...

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DSKE: dynamic set key encryption

Published in:
7th LCN Workshop on Security in Communications, 22 October 2012, pp. 1006-13.

Summary

In this paper, we present a novel paradigm for studying the problem of group key distribution, use it to analyze existing key distribution schemes, and then present a novel scheme for group key distribution which we call "Dynamic Set Key Encryption," or DSKE. DSKE meets the demands of a tactical environment while relying only on standard cryptographic primitives. Our "set key" paradigm allows us to focus on the underlying problem of establishing a confidential communication channel shared by a group of users, without concern for related security factors like authenticity and integrity, and without the need to consider any properties of the group beyond a list of its members. This separation of concerns is vital to our development and analysis of DSKE, and can be applied elsewhere to simplify the analyses of other group key distribution schemes.
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Summary

In this paper, we present a novel paradigm for studying the problem of group key distribution, use it to analyze existing key distribution schemes, and then present a novel scheme for group key distribution which we call "Dynamic Set Key Encryption," or DSKE. DSKE meets the demands of a tactical...

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Low power sparse polynomial equalizer (SPEQ) for nonlinear digital compensation of an active anti-alias filter

Published in:
Proc. 2012 IEEE Workshop on Signal Processing Systems, 17-19 October 2012, pp. 249-253.

Summary

We present an efficient architecture to perform on-chip nonlinear equalization of an anti-alias RF filter. The sparse polynomial equalizer (SPEq) achieves substantial power savings through co-design of the equalizer and the filter, which allows including the right number of processing elements, filter taps, and bits to maximize performance and minimize power consumption. The architecture was implemented in VHDL and fabricated in CMOS 65 nm technology. Testing results show that undesired spurs are suppressed to near the noise floor, improving the system's spur-free dynamic range by 25 dB in the median case, and consuming less than 12 mW of core power when operating at 200 MHz.
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Summary

We present an efficient architecture to perform on-chip nonlinear equalization of an anti-alias RF filter. The sparse polynomial equalizer (SPEq) achieves substantial power savings through co-design of the equalizer and the filter, which allows including the right number of processing elements, filter taps, and bits to maximize performance and minimize...

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Super-homogenous saturation of microwave-photonic gain in optoeletronic oscillator systems

Published in:
IEEE Photonics J., Vol. 4, No. 5, October 2012, pp. 1256-1266.
Topic:

Summary

We show that the saturation characteristic of microwave-photonic gain is "superhomogeneous" such that the gain of a weaker tone saturates more rapidly than that of a stronger tone when both signals are transmitted over an intensity-modulated optical link. Using this gain model, we simulate the effect of nonlinear gain saturation on the performance of a slab-coupled optical waveguide (SCOW)-based optoelectronic oscillator (OEO). We verify our simulations with experimental measurements and show that low sidemode levels (< -110 dBc) can be achieved even when multiple modes can oscillate within the passband of the OEO loop filter.
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Summary

We show that the saturation characteristic of microwave-photonic gain is "superhomogeneous" such that the gain of a weaker tone saturates more rapidly than that of a stronger tone when both signals are transmitted over an intensity-modulated optical link. Using this gain model, we simulate the effect of nonlinear gain saturation...

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Quantum simulator of an open quantum system using superconducting qubits: exciton transport in photosynthetic complexes

Published in:
New J. Phys., Vol. 14, October 2012, 105013.

Summary

Open quantum system approaches are widely used in the description of physical, chemical and biological systems. A famous example is electronic excitation transfer in the initial stage of photosynthesis, where harvested energy is transferred with remarkably high efficiency to a reaction center. This transport is affected by the motion of a structured vibrational environment, which makes simulations on a classical computer very demanding. Here we propose an analog quantum simulator of complex open system dynamics with a precisely engineered quantum environment. Our setup is based on superconducting circuits, a well established technology. As an example, we demonstrate that it is feasible to simulate exciton transport in the Fenna-Matthews-Olson photosynthetic complex. Our approach allows for a controllable single-molecule simulation and the investigation of energy transfer pathways as well as non-Markovian noise-correlation effects.
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Summary

Open quantum system approaches are widely used in the description of physical, chemical and biological systems. A famous example is electronic excitation transfer in the initial stage of photosynthesis, where harvested energy is transferred with remarkably high efficiency to a reaction center. This transport is affected by the motion of...

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Reversible electrowetting on dual-scale-patterned corrugated microstructured surfaces

Published in:
J. of Microeletromechanical Systems, Vol. 21, No. 5, October 2012, pp. 1261-71.

Summary

The ability to reversibly switch between a hydrophobic Cassie state and a hydrophilic Wenzel state is often not possible on textured surfaces because of energy barriers which result from the geometry of the microstructure. In this paper, we report on a simple microstructure geometry that allows an aqueous droplet to be reversibly switched between these states by the application of electrowetting. We demonstrate reversible electrowetting in air on microstructured surfaces consisting of parallel corrugations and show that this geometry can be engineered to produce a Cassie state and can be electrically controlled to switch to a Wenzel wetting state having high adhesion. When the electric field was removed, we observed spontaneous dewetting along the corrugations as the droplet transitioned from the Wenzel state back to a Cassie state.
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Summary

The ability to reversibly switch between a hydrophobic Cassie state and a hydrophilic Wenzel state is often not possible on textured surfaces because of energy barriers which result from the geometry of the microstructure. In this paper, we report on a simple microstructure geometry that allows an aqueous droplet to...

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Evaluation of the Convective Weather Avoidance Model for arrival traffic

Published in:
12th AIAA Aviation Technology, Integration, and Operations (ATIO) Conf. and 14th AIAA/ISSM, 17-19 September 2012.

Summary

The effective management of traffic flows during convective weather events in congested air space requires decision support tools that can translate weather information into anticipated air traffic operational impact. In recent years, MIT Lincoln Laboratory has been maturing the Convective Weather Avoidance Model (CWAM) to correlate pilot behavior in the enroute airspace with observable weather parameters from convective weather forecast systems. This paper evaluates the adaptation of the CWAM to terminal airspace with a focus on arrival decision making. The model is trained on data from five days of terminal convective weather impacts. The performance of the model is evaluated on an independent dataset consisting of six days of convective weather over a variety of terminal areas. Model performance in different terminal areas is discussed and the sensitivity of prediction accuracy to weather forecast horizon is presented.
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Summary

The effective management of traffic flows during convective weather events in congested air space requires decision support tools that can translate weather information into anticipated air traffic operational impact. In recent years, MIT Lincoln Laboratory has been maturing the Convective Weather Avoidance Model (CWAM) to correlate pilot behavior in the...

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Air traffic decision analysis during convective weather events in arrival airspace

Published in:
12th AIAA Aviation Technology, Integration, and Operations (ATIO) Conf. and 14th AIAA/ISSM, 17-19 September 2012.

Summary

Decision making during convective weather events in the terminal area is shared among pilots and air traffic management, where uninformed decisions can result in wide-spread cascading delays with high-level impacts. Future traffic management systems capable of predicting terminal impacts will mitigate these unnecessary delays; however in order to realize this vision, it is important to understand the decision mechanisms behind convective weather avoidance. This paper utilizes an arrival adaptation of the Convective Weather Avoidance Model (CWAM) to investigate the catalysts for arrival traffic management decision making. The analysis is broken down by category of terminal airspace structure in addition to the type of decision. The results show that pilot behavior in convective weather is heavily dependent on the terminal airspace structure. In addition, pilot and air traffic management decisions in convective weather can be discriminated with large-scale weather features.
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Summary

Decision making during convective weather events in the terminal area is shared among pilots and air traffic management, where uninformed decisions can result in wide-spread cascading delays with high-level impacts. Future traffic management systems capable of predicting terminal impacts will mitigate these unnecessary delays; however in order to realize this...

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An approach for estimating current and future benefits of airport surface congestion management techniques

Published in:
12th AIAA Aviation Technology, Integration, and Operations (ATIO) Conf. and 14th AIAA/ISSM, 17-19 September 2012.

Summary

Airport surface congestion can be a cause of significant increases in taxi times, fuel burn and emissions at major airports. Various surface congestion management techniques are being developed to help mitigate these issues at different airports, typically by holding aircraft at the gate during times of high congestion to reduce the number of aircraft on the active movement area. This paper presents an approach to estimate the benefits in terms of reductions in active taxi time and fuel burn of applying such techniques at a subset of US airports, both under current and expected future operations. Results show that the benefits of surface congestion management translate to billions of gallons of reduced fuel burn and huge environmental impact reduction over the next twenty years.
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Summary

Airport surface congestion can be a cause of significant increases in taxi times, fuel burn and emissions at major airports. Various surface congestion management techniques are being developed to help mitigate these issues at different airports, typically by holding aircraft at the gate during times of high congestion to reduce...

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