Analysis of Airspace Traffic Structure and Air Traffic Control Techniques

Air traffic controller cognitive processes are a limiting factor in providing safe and efficient flow of traffic. Therefore, there has been work in understanding the factors that drive controllers decision-making processes. Prior work has identified that the airspace structure, defined by the reference elements, procedural elements and pattern elements of the traffic, is important for abstraction and management of the traffic. This work explores in more detail this relationship between airspace structure and air traffic controller management techniques. This work looks at the current National Airspace System (NAS) and identifies different types of high altitude sectors, based on metrics that are likely to correlate with tasks that controllers have to perform. Variations of structural patterns, such as flows and critical points were also observed. These patterns were then related to groupings by origins and destinations of the traffic. Deeper pilot-controller voice communication analysis indicated that groupings by flight plan received consistent and repeatable sequences of commands, which were identified as techniques. These repeated modifications generated patterns in the traffic, which were naturally associated with the standard flight plan groupings and their techniques. The identified relationship between flight plan groupings and management techniques helps to validate the grouping structure-base abstraction introduced by Histon and Hansman (2008). This motivates the adoption of a grouping-focused analysis of traffic structures on the investigation of how new technologies, procedures and concepts of operations will impact the way controllers manage the traffic. Consideration of such mutual effects between structure and controllers' cognitive processes should provide a better foundation for training and for engineering decisions that include a human-centered perspective.This work was financially supported by FAA grant 06-G-006 and NASA Cooperative Agreement NN06CN23A. Anton Koros and Eddie Sierra were the technical sponsors and provided valuable feedback and assistance

Analysis of airspace traffic structure and air traffic control techniques

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2012.Cataloged from PDF version of thesis.Includes bibliographical references (p. 157-163).Air traffic controller cognitive processes are a limiting factor in providing safe and efficient flow of traffic. Therefore, there has been work in understanding the factors that drive controllers decision-making processes. Prior work has identified that the airspace structure, defined by the reference elements, procedural elements and pattern elements of the traffic, is important for abstraction and management of the traffic. This work explores in more detail this relationship between airspace structure and air traffic controller management techniques. This work looks at the current National Airspace System (NAS) and identifies different types of high altitude sectors, based on metrics that are likely to correlate with tasks that controllers have to perform. Variations of structural patterns, such as flows and critical points were also observed. These patterns were then related to groupings by origins and destinations of the traffic. Deeper pilot-controller voice communication analysis indicated that groupings by flight plan received consistent and repeatable sequences of commands, which were identified as techniques. These repeated modifications generated patterns in the traffic, which were naturally associated with the standard flight plan groupings and their techniques. The identified relationship between flight plan groupings and management techniques helps to validate the grouping structure-base abstraction introduced by Histon and Hansman (2008). This motivates the adoption of a grouping-focused analysis of traffic structures on the investigation of how new technologies, procedures and concepts of operations will impact the way controllers manage the traffic. Consideration of such mutual effects between structure and controllers' cognitive processes should provide a better foundation for training and for engineering decisions that include a human-centered perspective.by Emilio Alverne Falcão de Albuquerque Filho.S.M

Transport and Fate of Phosphorus in the Nearshore Zone of Lake Michigan

Bioavailable phosphorus loads exported to Lake Michigan from the Milwaukee and Sheboygan River Watersheds appear to have increased in the last 40 years despite meeting total phosphorus (TP) loading goals set by the Great Lakes Water Quality Agreement (GLWQA).Overall, bioavailability of P delivered from the Milwaukee and Sheboygan Rivers was highest during the warmer months, which coincides with the nearshore nuisance algae growth season. However, first order loss rates of SRP calculated during baseflow recession were also greatest during the summer, suggesting that increased river residence time during the summer could reduce export of bioavailable P. Observations of phosphorus partitioning combined with historic USGS monitoring data parallels trends seen in several Lake Erie watersheds with an increase in soluble reactive phosphorus (SRP) and decreases in particulate phosphorus (PP) export. Suspended sediment loads from the Milwaukee and Sheboygan watersheds are relatively P rich (mean 2.3 ± 0.66 ugP/mg) and relatively bioavailable at 39% and 33% respectively (using NaOH-extractable P as an index of bioavailability). Incubation experiments showed that over time river PP, and in particular NaOH-extractable P, releases P to the SRP pool. A seasonal increase in the PP:SRP ratio parallels increases in the percent bioavailability within the particulate P pool due to an increased contribution of NaOH-extractable P. This pattern coincides somewhat with prevalent midwest land use practices such as harvest of grain corn, but may also be driven by a combination of temperature and pH dependent coprecipitation and sorption phosphate buffering mechanisms on fine-grained particles that move SRP to the PP pool. However, this phosphate buffering mechanism may be offset by land use practices that increase soil P-Content, reducing the number of SRP sorption sites on particles. Moreover, P-rich fine-grained particles that do not settle in harbors but are discharged to the nearshore may desorb phosphate due to changes in equilibrium kinetics. Upon entering the lake, fine-grained P-rich particles can be intercepted by invasive mussel filtration, potentially releasing SRP to nearshore nuisance algae and thereby increasing the retention of P within the nearshore zone. Nearshore lake sediments were collected to test this hypothesis by examining lake sediments for fine-grained particles with high sorption capacity. Sorption experiments revealed that particles with high sorption capacity were present in the sediments. P-content saturation kinetics were modeled as a function of initial P-content, initial SRP concentration, and time. Results indicate that, though multiple size fractions of sediment exist in the lake sediment, it is the small (\u3c 30 µm) fine-grained particles that have the highest sorption capacity. Invasive quagga mussels were “fed” a variety of PP sources including algae culture, lake sediments (bulk and fine-grained), and river water in laboratory experiments. Mussel filtration rates did not appear to be affected by food source “quality”. Likewise, with the exception of P-rich fine-grained particles, food source quality did not seem to affect mussel excretion rates. Throughout mussel experiments, excretion rates rarely differed from baseline (i.e. control) rates. However, feeding on fine-grained particles resulted in significantly greater SRP excretion rates, which may be due to release of loosely sorbed P on these particles. Bulk egestion (i.e. the production of feces and pseudofeces), was regulated by initial TSS concentrations within the feeding chamber. The initial P-content of particulates fed to mussels was compared with the P-content in egested material. For most food groups, P content declined following passage through the mussel gut. The percent change in P-content varied from 15 – 75 % depending on food source. The only exception was bulk lake sediments, which had a very low initial P-content (i.e. ~0.8 µg/mg). This work provides more evidence that supports the nearshore shunt hypothesis and suggests that tighter restrictions of non-point source P loading may be necessary. River restoration projects that increase river residence time and phosphate assimilation are likely valuable and may be quantifiable with calculations of first order SRP loss rates. Natural phosphate buffering mechanisms such as coprecipitation and sorption may provide a phosphate management tool, but should be paired with management actions that reduce upstream soil P-content and enhance in-route particle settling through increased residence time. Mussels continue to pose a management challenge, but better mechanistic understanding of processes affecting PP quality, transport, and mussel digestion may inform modeling efforts that identify optimal management strategies for the nearshore zone

Neo-liberalism and the Korean Economy since the 1997 Financial Crisis: A Christian Ethical Analysis centering upon Tax Havens, Labor-Management Relations and Real Estate

Reinders, J.S. [Promotor]Goudzwaard, B. [Copromotor

Beiträge zu Business Intelligence und IT-Compliance

[no abstract

Quantitative inquiry into Federal Aviation Administration Flight Inspection Services Safety Significant Events

The purpose of this case study of the FAA, Flight Inspection Services Safety Significant Events database from 2009 through 2012 was to discover if there are relationships between a set of independent variables and the dependent variable of a reportable event. These independent variables were categorized by Year, Month, Day, Hour, Phase of Flight, Aircraft System, and Fleet Type in which they occurred. This will help determine safety trends of events that occur in flight or on the ground that affect, or could affect, the safety of an FAA aircraft or aircrew member. The study should not only benefit the organization by providing a categorical perspective from which future decisions may be enriched, but should also serve as an educational resource to other CFR Part 135 Operators

Developing the KMKE knowledge management system based on design patterns and parallel processing

[[abstract]]KMKE provides a knowledge engineering approach to integrating knowledge management activities (such as knowledge modeling, knowledge verification, knowledge storage and knowledge querying) into a systematic framework. In this paper, we develop the KMKE knowledge management system based on design patterns and parallel processing. First, several design patterns are applied to develop the KMKE system for enhancing its flexibility and extensibility. Making the KMKE system flexible and extensible is useful to deal with continuous changes originated in knowledge. Second, JAVA programs and CLIPS programs are bound to offer the capability of knowledge inference for the KMKE system. Knowledge verification and knowledge querying can then be performed through the execution of CLIPS rules. Finally, we propose the Parallel CLIPS to shorten the execution time of the KMKE system. Since a large amount of knowledge may increase the execution time substantially, parallelizing the execution of CLIPS rules in cluster system could effectively reduce the search space of the CLIPS inference engine

GVSU Press Releases, 1972

A compilation of press releases for the year 1972 submitted by University Communications (formerly News & Information Services) to news agencies concerning the people, places, and events related to Grand Valley State University