5 research outputs found

    Development of Complexity Science and Technology Tools for NextGen Airspace Research and Applications

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    The objective of this research by NextGen AeroSciences, LLC is twofold: 1) to deliver an initial "toolbox" of algorithms, agent-based structures, and method descriptions for introducing trajectory agency as a methodology for simulating and analyzing airspace states, including bulk properties of large numbers of heterogeneous 4D aircraft trajectories in a test airspace -- while maintaining or increasing system safety; and 2) to use these tools in a test airspace to identify possible phase transition structure to predict when an airspace will approach the limits of its capacity. These 4D trajectories continuously replan their paths in the presence of noise and uncertainty while optimizing performance measures and performing conflict detection and resolution. In this approach, trajectories are represented as extended objects endowed with pseudopotential, maintaining time and fuel-efficient paths by bending just enough to accommodate separation while remaining inside of performance envelopes. This trajectory-centric approach differs from previous aircraft-centric distributed approaches to deconfliction. The results of this project are the following: 1) we delivered a toolbox of algorithms, agent-based structures and method descriptions as pseudocode; and 2) we corroborated the existence of phase transition structure in simulation with the addition of "early warning" detected prior to "full" airspace. This research suggests that airspace "fullness" can be anticipated and remedied before the airspace becomes unsafe

    Finishing the euchromatic sequence of the human genome

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    The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

    Biased Eukaryotic Gene Regulation Rules Suggest Genome Behavior Is Near Edge Of Chaos

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    Introduction The present article reports an analysis of data pertaining to certain biases in the observed patterns of transcription regulation of eukaryotic genes. In the Boolean idealization, a small subset of possible switching rules, the canalizing functions, are highly utilized. To draw inferences about the implications of the observed biases, a statistical ensemble approach was used. Representative networks constructed within the ensemble of networks that satisfy the biases were studied numerically. The consequences indicate that modeled genomic regulatory systems are in a dynamical "ordered" regime, measurably close to a transition to a "chaotic" regime. A number of testable consequences are derived. Section 2 Transcription State Spaces, Trajectories, Attractors, and Boolean Net Models A state space is a mathematical abstraction used to describe a dynamical system consisting of a number of interacting variables. The human genomic regulator

    Welfare Reform in Philadelphia: Implementation, Effects, and Experiences of Poor Families and Neighborhoods

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