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

September 17, 2012
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Conference Paper
Author:
Alex H. Nakahara
…
Published in:
12th AIAA Aviation Technology, Integration, and Operations (ATIO) Conf. and 14th AIAA/ISSM, 17-19 September 2012.
Topic:
air traffic control
R&D area:
R&D group:

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

Air traffic decision analysis during convective weather events in arrival airspace

September 17, 2012
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Conference Paper
Author:
Scot E. Campbell
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Published in:
12th AIAA Aviation Technology, Integration, and Operations (ATIO) Conf. and 14th AIAA/ISSM, 17-19 September 2012.
Topic:
air traffic management
R&D area:
R&D group:

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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Air traffic decision analysis during convective weather events in arrival airspace

Evaluation of the Convective Weather Avoidance Model for arrival traffic

September 17, 2012
  |
Conference Paper
Author:
Scot E. Campbell
…
Published in:
12th AIAA Aviation Technology, Integration, and Operations (ATIO) Conf. and 14th AIAA/ISSM, 17-19 September 2012.
Topic:
air traffic management
R&D area:
R&D group:

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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Evaluation of the Convective Weather Avoidance Model for arrival traffic

Wind information requirements to support Four Dimensional Trajectory-Based Operations

September 17, 2012
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Conference Paper
Author:
Yan Glina
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Published in:
12th AIAA Aviation Technology, Integration, and Operations (ATIO) Conf. and 14th AIAA/ISSM, 17-19 September 2012.
Topic:
air traffic control
R&D area:
R&D group:

Summary

Accurate wind information is required to support some of the key applications envisioned for future air traffic concepts. A Wind Information Analysis Framework is described to assess wind information needs for different applications. The framework is applied in a Four-Dimensional Trajectory Based Operations (4D-TBO) application using simplified versions of the framework's elements to demonstrate its utility. Realistic ranges of wind information accuracy limitations in terms of wind forecast and Flight Management System wind representation errors are studied. Their impacts on 4D-TBO performance in terms of Required Time of Arrival compliance and fuel burn are presented. Interpretations of the findings to determine wind information requirements are provided.
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Summary

Accurate wind information is required to support some of the key applications envisioned for future air traffic concepts. A Wind Information Analysis Framework is described to assess wind information needs for different applications. The framework is applied in a Four-Dimensional Trajectory Based Operations (4D-TBO) application using simplified versions of the...

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Wind information requirements to support Four Dimensional Trajectory-Based Operations

Measurements of the 1030 and 1090 MHz environments at JFK International Airport

September 12, 2012
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Project Report
Author:
Adam Panken
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Published in:
MIT Lincoln Laboratory Report ATC-390
Topic:
mode S data links
R&D area:
R&D group:

Summary

Measurements of signals in the 1030 and 1090 MHz frequency bands have been made by MIT Lincoln Laboratory in the last several years, previously in the Boston area and most recently in April 2011, at JFK International Airport near New York City. This JFK measurement activity was performed as a part of the Lincoln Laboratory Traffic Alert and Collision Avoidance System (TCAS) work for the Federal Aviation Administration (FAA) and is the subject of this report. This report includes: 1) Overall characteristics of the 1030/1090 MHz environments, 2) Analysis of the TCAS air-to-air coordination process, 3) Examination of 1090 MHz Extended Squitter transmissions for use in TCAS, 4) Assessment of the extent and impact of TCAS operation on the airport surface.
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Summary

Measurements of signals in the 1030 and 1090 MHz frequency bands have been made by MIT Lincoln Laboratory in the last several years, previously in the Boston area and most recently in April 2011, at JFK International Airport near New York City. This JFK measurement activity was performed as a...

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Measurements of the 1030 and 1090 MHz environments at JFK International Airport

High dynamic range suppressed-bias microwave photonic links using unamplified semiconductor laser source

September 11, 2012
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Conference Paper
Author:
Sivasubramaniam S. Yegnanarayanan
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Published in:
AVFOP 2012: IEEE Avionics, Fiber-Optics and Photonics Tech. Conf., 11-13 September 2012, pp. 28-9.
Topic:
optics
R&D area:
R&D group:

Summary

Microwave photonic (MWP) links with a low noise figure and high dynamic range are required for antenna remoting, radio-over-fiber (RoF), and other advanced applications. MWP links have recently been demonstrated with noise figures approaching 3 dB, without any electrical preamplification, by using low-noise high-power laser sources in conjunction with efficient optical intensity modulators and high-power photodetectors. An alternate approach to noise figure reduction, suitable for sub-octave links, is based on using a high-power laser source and shifting the bias point of an external optical intensity modulator to reduce the average photocurrent and suppress excess link noise. Here, we report the performance of a novel slab-coupled optical waveguide external-cavity laser (SCOWECL) in a suppressed bias MWP link. We compare the performance of this link with a suppressed-bias link using a source comprising a commercial-off-the-shelf (COTS) laser and erbium-doped fiber amplifier (EDFA) and show that MWP links built using SCOW-based emitter technology offer superior performance due to the small-form factor, high-efficiency, low-noise, and high power laser source.
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Summary

Microwave photonic (MWP) links with a low noise figure and high dynamic range are required for antenna remoting, radio-over-fiber (RoF), and other advanced applications. MWP links have recently been demonstrated with noise figures approaching 3 dB, without any electrical preamplification, by using low-noise high-power laser sources in conjunction with efficient...

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High dynamic range suppressed-bias microwave photonic links using unamplified semiconductor laser source

Driving big data with big compute

September 10, 2012
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Conference Paper
Author:
Chansup Byun
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Published in:
HPEC 2012: IEEE Conf. on High Performance Extreme Computing, 10-12 September 2012.
Topic:
supercomputing
R&D area:
R&D group:

Summary

Big Data (as embodied by Hadoop clusters) and Big Compute (as embodied by MPI clusters) provide unique capabilities for storing and processing large volumes of data. Hadoop clusters make distributed computing readily accessible to the Java community and MPI clusters provide high parallel efficiency for compute intensive workloads. Bringing the big data and big compute communities together is an active area of research. The LLGrid team has developed and deployed a number of technologies that aim to provide the best of both worlds. LLGrid MapReduce allows the map/reduce parallel programming model to be used quickly and efficiently in any language on any compute cluster. D4M (Dynamic Distributed Dimensional Data Model) provided a high level distributed arrays interface to the Apache Accumulo database. The accessibility of these technologies is assessed by measuring the effort to use these tools and is typically a few lines of code. The performance is assessed by measuring the insert rate into the Accumulo database. Using these tools a database insert rate of 4M inserts/second has been achieved on an 8 node cluster.
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Summary

Big Data (as embodied by Hadoop clusters) and Big Compute (as embodied by MPI clusters) provide unique capabilities for storing and processing large volumes of data. Hadoop clusters make distributed computing readily accessible to the Java community and MPI clusters provide high parallel efficiency for compute intensive workloads. Bringing the...

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Driving big data with big compute

HPC-VMs: virtual machines in high performance computing systems

September 10, 2012
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Journal Article
Author:
Albert I. Reuther
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Published in:
HPEC 2012: IEEE Conf. on High Performance Extreme Computing, 10-12 September 2012.
Topic:
supercomputing
R&D area:
R&D group:

Summary

The concept of virtual machines dates back to the 1960s. Both IBM and MIT developed operating system features that enabled user and peripheral time sharing, the underpinnings of which were early virtual machines. Modern virtual machines present a translation layer of system devices between a guest operating system and the host operating system executing on a computer system, while isolating each of the guest operating systems from each other. In the past several years, enterprise computing has embraced virtual machines to deploy a wide variety of capabilities from business management systems to email server farms. Those who have adopted virtual deployment environments have capitalized on a variety of advantages including server consolidation, service migration, and higher service reliability. But they have also ended up with some challenges including a sacrifice in performance and more complex system management. Some of these advantages and challenges also apply to HPC in virtualized environments. In this paper, we analyze the effectiveness of using virtual machines in a high performance computing (HPC) environment. We propose adding some virtual machine capability to already robust HPC environments for specific scenarios where the productivity gained outweighs the performance lost for using virtual machines. Finally, we discuss an implementation of augmenting virtual machines into the software stack of a HPC cluster, and we analyze the affect on job launch time of this implementation.
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Summary

The concept of virtual machines dates back to the 1960s. Both IBM and MIT developed operating system features that enabled user and peripheral time sharing, the underpinnings of which were early virtual machines. Modern virtual machines present a translation layer of system devices between a guest operating system and the...

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HPC-VMs: virtual machines in high performance computing systems

Large scale network situational awareness via 3D gaming technology

September 10, 2012
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Conference Paper
Author:
Matthew Hubbell
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Published in:
HPEC 2012: IEEE Conf. on High Performance Extreme Computing, 10-12 September 2012.
Topic:
supercomputing
R&D area:
R&D group:

Summary

Obtaining situational awareness of network activity across an enterprise presents unique visualization challenges. IT analysts are required to quickly gather and correlate large volumes of disparate data to identify the existence of anomalous behavior. This paper will show how the MIT Lincoln Laboratory LLGrid Team has approached obtaining network situational awareness utilizing the Unity 3D video game engine. We have developed a 3D environment of the physical plant in the format of a networked multi player First Person Shooter (FPS) to demonstrate a virtual depiction of the current state of the network and the machines operating on the network. Within the game or virtual world an analyst or player can gather critical information on all network assets as well as perform physical system actions on machines in question. 3D gaming technology provides tools to create an environment that is both visually familiar to the player as well display immense amounts of system data in a meaningful and easy to absorb format. Our prototype system was able to monitor and display 5000 assets in ~10% of the time of our network time window.
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Summary

Obtaining situational awareness of network activity across an enterprise presents unique visualization challenges. IT analysts are required to quickly gather and correlate large volumes of disparate data to identify the existence of anomalous behavior. This paper will show how the MIT Lincoln Laboratory LLGrid Team has approached obtaining network situational...

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Large scale network situational awareness via 3D gaming technology

Scalable cryptographic authentication for high performance computing

September 10, 2012
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Conference Paper
Author:
Andrew J. Prout
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Published in:
HPEC 2012: IEEE Conf. on High Performance Extreme Computing, 10-12 September 2012.
Topic:
supercomputing
R&D area:
R&D group:

Summary

High performance computing (HPC) uses supercomputers and computing clusters to solve large computational problems. Frequently HPC resources are shared systems and access to restricted data sets or resources must be authenticated. These authentication needs can take multiple forms, both internal and external to the HPC cluster. A computational stack that uses web services among nodes in the HPC may need to perform authentication between nodes of the same job or a job may need to reach out to data sources outside the HPC. Traditional authentication mechanisms such as passwords or digital certificates encounter issues with the distributed and potentially disconnected nature of HPC systems. Distributing and storing plain-text passwords or cryptographic keys among nodes in a HPC system without special protection is a poor security practice. Systems that reach back to the user's terminal for access to the authenticator are possible, but only in fully interactive supercomputing where connectivity to the user's terminal can be guaranteed. Point solutions can be enabled for these use cases, such as software-based role or self-signed certificates, however they require significant expertise in digital certificates to configure. A more general solution is called for that is both secure and easy to use. This paper presents an overview of a solution implemented on the interactive, on-demand LLGrid computing system at MIT Lincoln Laboratory and its use to solve one such authentication problem.
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Summary

High performance computing (HPC) uses supercomputers and computing clusters to solve large computational problems. Frequently HPC resources are shared systems and access to restricted data sets or resources must be authenticated. These authentication needs can take multiple forms, both internal and external to the HPC cluster. A computational stack that...

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Scalable cryptographic authentication for high performance computing
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