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61.
Karen Goodnough 《Canadian Journal of Science, Mathematics, & Technology Education》2013,13(3):289-306
Abstract: In this self‐study, the author gained in‐depth understanding of how to plan and implement problem‐based learning (PBL), a student‐centred approach to teaching and learning that is driven by messy, open‐ended problems. This paper focuses primarily on the issues and concerns that arose as she developed and implemented a modified form of traditional PBL (Barrows, 1996) in large, pre‐service science‐teacher education classes. To view the research from many perspectives, a variety of data collection methods and sources were used, including field notes, semi‐structured interviews, student‐generated documents, and student journals. The outcomes of this study describe challenges (problem development, facilitation of groups, and assessment) encountered by the author as she planned for and implemented PBL. Furthermore, changes in the author's classroom practice, the connection between these changes and constructivist learning principles, and implications for science‐teacher education are addressed. 相似文献
62.
This paper is concerned with the elimination of unnecessary states in discrete-event system control agents. Several approaches
to supervisor reduction are studied and a new relation between agents, comparability, is defined to encapsulate most of the concepts found in the aforementioned methods. This relation is also proven to be preserved
under conjunction, which is commonly employed to determine the centralized representation of two decentralized DES supervisors.
相似文献
Karen RudieEmail: |
63.
64.
Summary The general equations for the radiation dose dependence of irradiated polymer molecular weights have been solved exactly. For an initial most probable molecular weight distribution (=1), the solutions are analytical and exact. For the general case (1) the solutions are numerical and exact. The present approach has resulted in the solutions for both =1 and 1 being incorporated into a group of FORTRAN computer programs which will solve experimental data for scission and crosslinking yields by both minimization and exact treatments. Simulated data treated using these FORTRAN programs are give. The FORTRAN programs are available from the authors. 相似文献
65.
Flanagan Karen; Walshaw John; Price Sarah L.; Goodfellow Julia M. 《Protein engineering, design & selection : PEDS》1995,8(2):109-116
The interaction of water molecules with apolar amino acids isan important aspect of the hydrophobic effect and hence of proteinfolding. Our distributed multipole electrostatic model for waterinteracting with phenylalanine dipeptides shows that minimumenergy sites exist above the aromatic ring such that a solventmolecule can interact with the electrons, but only when thissite is not blocked by mainchain atoms or disturbed by main-chainpolar atoms. This is consistent with the experimental evidenceof others that water can hydrogen bond to aromatic n electrons.In contrast, our analysis of solvent interactions with phenylalanineresidues based on 48 high-resolution, well-refined protein structuresshows that the dominant interaction of solvent molecules iswith the edge of the ring and not with the 7i electrons. Asthe faces of phenylalanine rings tend to be buried, and solventinteractions with neighbouring polar atoms are more favourable,the interaction of water molecules with the faces of aromatic rings appears not to occur frequently in proteins 相似文献
66.
High Figure of Merit (FOM) of Bragg Modes in Au‐Coated Nanodisk Arrays for Plasmonic Sensing
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Maxime Couture Thibault Brulé Stacey Laing Wenli Cui Mitradeep Sarkar Benjamin Charron Karen Faulds Wei Peng Michael Canva Jean‐Francois Masson 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(38)
Gold‐coated nanodisk arrays of nearly micron periodicity are reported that have high figure of merit (FOM) and sensitivity necessary for plasmonic refractometric sensing, with the added benefit of suitability for surface‐enhanced Raman scattering (SERS), large‐scale microfabrication using standard photolithographic techniques and a simple instrumental setup. Gold nanodisk arrays are covered with a gold layer to excite the Bragg modes (BM), which are the propagative surface plasmons localized by the diffraction from the disk array. This generates surface‐guided modes, localized as standing waves, leading to highly confined fields confirmed by a mapping of the SERS intensity and numerical simulations with 3D finite element method. The optimal gold‐coated nanodisk arrays are applied for refractometric sensing in transmission spectroscopy with better performance than nanohole arrays and they are integrated to a 96‐well plate reader for detection of IgY proteins in the nanometer range in PBS. The potential for sensing in biofluids is assessed with IgG detection in 1:1 diluted urine. The structure exhibits a high FOM of up to 46, exceeding the FOM of structures supporting surface plasmon polaritons and comparable to more complex nanostructures, demonstrating that subwavelength features are not necessary for high‐performance plasmonic sensing. 相似文献
67.
68.
Karen M. Feigh Matthew J. Miller Raunak P. Bhattacharyya Minyue Ma Samantha Krening Yosef Razin 《Theoretical Issues in Ergonomics Science》2018,19(4):389-405
Human factors practitioners (HFPs) play many different roles in the design, creation, operation and maintenance of engineered systems. Less well known are the methods which are aimed at helping with the early stages of design, which are more systems-oriented and often involve questions of the concept of operation in which the engineered system will be fielded. Emerging from the field of cognitive engineering, these methods, including simulation, cognitive work analysis, cognitive task analyses and hierarchical task analysis, will be important as autonomous systems become increasingly capable. Even the most capable systems will continue to interact with humans, and it is at these interfaces between humans and engineered systems that HFP will continue to be needed. This paper describes recent work to leverage these methods to inform concepts of operation in aviation and space, machine learning algorithms and goal-oriented human–machine collaboration. 相似文献
69.
70.
Dimitra?Giannakopoulou David?H.?Bushnell Johann?SchumannEmail author Heinz?Erzberger Karen?Heere 《Annals of Mathematics and Artificial Intelligence》2011,63(1):5-30
In order to address the rapidly increasing load of air traffic operations, innovative algorithms and software systems must
be developed for the next generation air traffic control. Extensive verification of such novel algorithms is key for their
adoption by industry. Separation assurance algorithms aim at predicting if two aircraft will get closer to each other than
a minimum safe distance; if loss of separation is predicted, they also propose a change of course for the aircraft to resolve
this potential conflict. In this paper, we report on our work towards developing an advanced testing framework for separation
assurance. Our framework supports automated test case generation and testing, and defines test oracles that capture algorithm
requirements. We discuss three different approaches to test-case generation, their application to a separation assurance prototype,
and their respective strengths and weaknesses. We also present an approach for statistical analysis of the large numbers of
test results obtained from our framework. 相似文献