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Framing resistance: How Hamas uses collective action frames to attract and maintain human resources
The purpose of this study is to investigate the use of collective action framing mechanisms and processes by Hamas in order to aquire and maintain potential and existing human resources and to help researchers and scholars of contentious politics and social movement theory to gain a greater understanding of the role frames play in that decision by showing the ways social movement entrepreneurs use them to acquire, maintain, and motivate human resources for the purpose of collective action
Synthetic approaches to rhodomycinone and olivin
Intermediates for the synthesis of olivin and rhodomycinone were prepared by a sequence involving a Diels-Alder reaction followed by a Friedel-Crafts cyclization. In all cases optimal yields were obtained by regioselective methanolysis of anhydrides 9,10, and 21 followed by treatment of the crude ester acids with trifluoroacetic anhydride. An added advantage of the latter reaction is that aromatization also occurs
Synthesis of novel 6-deoxyanthracyclines
An extremely direct route to the 6-deoxyanthracycline skeleton is described. The initial route to quinone 10 failed due to an unexpected complication in the Ago demethylation step. However, starting from 2-bromo- 1,4-dimethoxynaphthalene, furan 17 could be prepared in two steps. Furan 17 was then converted into anthraquinone 19 in five steps. The eight-step route proceeds in 9% overall yield
The stories of Andrei Bitov, 1958-1966: a search for individual perception
The thesis traces and analyses Andrei Bitov's development from literary impressionist and short-story writer of the late fifties to philosopher and novelist of the mid-sixties. The writer's search for vision and idea is revealed through a detailed chronological study of each major work and cycle of short stories. The progression of Bitov's solitary hero through successive stages of childhood, adolescence and adulthood and his interaction with everyday problems follow a particular pattern towards self-perception. Although not a moralist, the writer guides the reader on an inward search for self-knowledge through his characters' experiences including both religious and mystical revelations. In addition to the treatment of the common themes of life, death and growing-up, Bitov gives literary expression to Zen Buddhist notions of Koan and Satori and reinterprets the nineteenth century concept of poshlost in the new idea of poluson. The usual classification of Bitov as a "psychological" writer of molodaya proza is viewed as too narrow a definition despite the outward appearance of "confessionalism" and storylines concerning the alienated young man. The year I966 is taken as the end of Bitov's early phase with the completion of the novel Dni cheloveka and the beginnings of Pushkinsky dom. The mid-sixties mark a transition in Bitov's search from one of idea to one of form and style. The thesis seeks to throw new light on Andrei Bitov's contribution tithe Soviet short story of the sixties with a reappraisal of both the nature and progression of his writing, and the inclusion of original unpublished material from Bitov himself
Mission Planner Algorithm for Urban Air Mobility Initial Performance Characterization
In this paper, an initial characterization was performed of the Mission Planner algorithm developed by NASA for Urban Air Mobility (UAM) operations research. The algorithm plans conflict-free trajectories for flights to support a given set of UAM passenger trips. The UAM trips are planned in an on-demand, first-come, first-served manner, such that any given trip is subject to the constraints imposed by previously planned trips. For this analysis, the mission planning algorithm considered only the trajectory constraints from previously-planned trips in one test condition and added vertiport constraints for the second test condition. The conflict and constraint resolution strategies used by the Mission Planner were characterized by their percentage contribution to planning iterations, their percentage effectiveness in those iterations, and their contributions to the departure delay applied to each UAM trips flight. With the exception of the climb and descent vertical speed strategies, most strategies showed reasonable or good performance in all test scenarios. In the test condition with vertipad constraints enabled, both the total number of iterations executed, and the number of flights that required planning iterations, was reduced for all scenarios. This was the result of the natural conditioning of the traffic achieved with scheduling and the additional information available to the Mission Planner from the vertiport scheduler. The next steps for this work will include improvements to the mission planning strategies and analyses with additional constraints and under other demand scenarios
Improvements to deep convolutional neural networks for LVCSR
Deep Convolutional Neural Networks (CNNs) are more powerful than Deep Neural
Networks (DNN), as they are able to better reduce spectral variation in the
input signal. This has also been confirmed experimentally, with CNNs showing
improvements in word error rate (WER) between 4-12% relative compared to DNNs
across a variety of LVCSR tasks. In this paper, we describe different methods
to further improve CNN performance. First, we conduct a deep analysis comparing
limited weight sharing and full weight sharing with state-of-the-art features.
Second, we apply various pooling strategies that have shown improvements in
computer vision to an LVCSR speech task. Third, we introduce a method to
effectively incorporate speaker adaptation, namely fMLLR, into log-mel
features. Fourth, we introduce an effective strategy to use dropout during
Hessian-free sequence training. We find that with these improvements,
particularly with fMLLR and dropout, we are able to achieve an additional 2-3%
relative improvement in WER on a 50-hour Broadcast News task over our previous
best CNN baseline. On a larger 400-hour BN task, we find an additional 4-5%
relative improvement over our previous best CNN baseline.Comment: 6 pages, 1 figur
Towards a Formal Semantics of Flight Plans and Trajectories
In the National Airspace System, ight plans are often used only as a planning tool by air trac controllers and aircraft operators. These plans are implicitly translated into trajectories by the pilot or by the ight management system, and subsequently own by the aircraft. This translation process inevitably introduces di erences between the plan and the trajectory. However, given the current intended usage, exact correspondence between the plan and the trajectory is not needed. To achieve greater capacity and eciency, future air trac management concepts are being designed around the use of trajectories where predictability is extremely important. In this paper, a mathematical relationship between ight plans and trajectories is explored with the goal of making feasible, highly accurate predictions of future positions and velocities of aircraft. The goal here is to describe, in mathematically precise detail, a formal language of trajectories, whereby all receivers of the trajectory information will be able to arrive at precisely the same trajectory predication and to do this without having aircraft broadcast a large amount of data. Although even a four-dimensional ight plan is simple in structure, this paper will show that it is inherently ambiguous and will explore these issues in detail. In e ect, we propose that a rigorous semantics for ight plans can be developed and this will serve as an important stepping stone towards trajectory-based operations in the National Airspace System
Comparison of Aircraft Models and Integration Schemes for Interval Management in the TRACON
Reusable models of common elements for communication, computation, decision and control in air traffic management are necessary in order to enable simulation, analysis and assurance of emergent properties, such as safety and stability, for a given operational concept. Uncertainties due to faults, such as dropped messages, along with non-linearities and sensor noise are an integral part of these models, and impact emergent system behavior. Flight control algorithms designed using a linearized version of the flight mechanics will exhibit error due to model uncertainty, and may not be stable outside a neighborhood of the given point of linearization. Moreover, the communication mechanism by which the sensed state of an aircraft is fed back to a flight control system (such as an ADS-B message) impacts the overall system behavior; both due to sensor noise as well as dropped messages (vacant samples). Additionally simulation of the flight controller system can exhibit further numerical instability, due to selection of the integration scheme and approximations made in the flight dynamics. We examine the theoretical and numerical stability of a speed controller under the Euler and Runge-Kutta schemes of integration, for the Maintain phase for a Mid-Term (2035-2045) Interval Management (IM) Operational Concept for descent and landing operations. We model uncertainties in communication due to missed ADS-B messages by vacant samples in the integration schemes, and compare the emergent behavior of the system, in terms of stability, via the boundedness of the final system state. Any bound on the errors incurred by these uncertainties will play an essential part in a composable assurance argument required for real-time, flight-deck guidance and control systems,. Thus, we believe that the creation of reusable models, which possess property guarantees, such as safety and stability, is an innovative and essential requirement to assessing the emergent properties of novel airspace concepts of operation
Stratway: A Modular Approach to Strategic Conflict Resolution
In this paper we introduce Stratway, a modular approach to finding long-term strategic resolutions to conflicts between aircraft. The modular approach provides both advantages and disadvantages. Our primary concern is to investigate the implications on the verification of safety-critical properties of a strategic resolution algorithm. By partitioning the problem into verifiable modules much stronger verification claims can be established. Since strategic resolution involves searching for solutions over an enormous state space, Stratway, like most similar algorithms, searches these spaces by applying heuristics, which present especially difficult verification challenges. An advantage of a modular approach is that it makes a clear distinction between the resolution function and the trajectory generation function. This allows the resolution computation to be independent of any particular vehicle. The Stratway algorithm was developed in both Java and C++ and is available through a open source license. Additionally there is a visualization application that is helpful when analyzing and quickly creating conflict scenarios
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