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101.
Joshua F. Hoops 《Journal of Intercultural Communication Research》2014,43(1):64-86
Emphasizing symbolic/material intersections, I employ a spatial approach to contextualize whiteness in migrant farm communities in Washington state. Specifically, I argue that white identity is not detached from physical settings, but evolves in relationship to others in these concrete, but symbolically constructed, locations. Utilizing observations, interviews, and ethnographic mapping, I discuss how participants’ spatial narratives elucidate pioneer and “multicultural” expressions of whiteness. The citation of an agricultural ethos also pervades discourses of whiteness in this community. These specific articulations signal the resiliency of whiteness to morph in response to perceived threats to its position and assuage anxiety over demographic changes. 相似文献
102.
Allen JR O'Keefe KB McCue TJ Borger JJ Hahn ME 《Sports biomechanics / International Society of Biomechanics in Sports》2008,7(1):38-53
Fly-fishing is a popular form of recreation. Recent evidence has associated overhand fly-casting movements with upper extremity pain. However, little research exists on the motions and coordination common to fly-casting. The aim of this study was to establish upper extremity kinematic trends of fly-casting while casting greater line lengths. It was hypothesized that kinematic casting parameters would increase and time between peak angular velocities would decrease with greater line length. Eighteen males participated in the study. Three-dimensional motion capture was conducted to calculate shoulder, elbow, and wrist kinematics during casting conditions of 6.1, 12.2, 18.3, and 24.4 m of line. Multiple analyses of variance were used to assess the condition effect of line length on the kinematic variables (P = 0.05). Overall, total range of movement increased with increasing length of line cast. Peak angular velocity exhibited a proximal-to-distal trend: peak shoulder internal rotation followed by elbow extension, then wrist ulnar deviation. Time between peak shoulder and elbow angular velocities increased significantly as line length increased. Our findings indicate that specific changes in total range of movement accommodate the demands of casting greater lengths of line. Also, joint velocity coordination patterns of fly-casting appear to follow a proximal-to-distal pattern. These findings represent an initial foundation for connections between kinematics and upper extremity pain reported by fly-fisherman. 相似文献
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In certain classification problems there is a strong a asymmetry between the number of labeled examples available for each of the classes involved. In an extreme case, there may be a complete lack of labeled data for one of the classes while, at the same time, there are adequate labeled examples for the others, accompanied by a large body of unlabeled data. Since most classification algorithms require some information about all classes involved, label estimation for the un-represented class is desired. An important representative of this group of problems is that of user interest/preference modeling where there may be a large number of examples of what the user likes with essentially no counterexamples.Recently, there has been much interest in applying the EM algorithm to incomplete data problems in the area of text retrieval and categorization. We adapt this approach to the asymmetric case of modeling user interests in news articles, where only labeled positive training data are available, with access to a large corpus of unlabeled documents. User modeling is here equivalent to that of user-specific document ranking. EM is used in conjunction with the Naive Bayes model while its output is also utilized by a Support Vector Machine and Rocchio's technique.Our findings demonstrate that the EM algorithm can be quite effective in modeling the negative class under a number of different initialization schemes. Although primarily just the negative training examples are needed, a natural question is whether using all of the estimated labels (i.e., positive and negative) would be more (or less) beneficial. This is important considering that, in this context, the initialization of the negative class for EM is likely not to be very accurate. Experimental results suggest that EM output should be limited to negative label estimates only. 相似文献
105.
Digital reference service adds a valuable new dimension to health science reference services, but the road to implementation can present questions that require carefully considered decisions. This article incorporates suggestions from the published literature, provides tips from interviews with practicing academic health science librarians, and reports on data from students' exploration of academic health science library Web sites' digital reference services. The goal of this study is to provide guidelines to plan new services, assess user needs, and select software, and to showcase potential benefits of collaboration and proactive and user-friendly marketing. In addition, tips for successful operation and evaluation of services are discussed. 相似文献
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Educational technology research and development - This paper is in response to the article entitled “A design framework for enhancing engagement in student-centered learning: own it, learn... 相似文献
108.
Tracy A. Kugler David C. Van Riper Steven M. Manson David A. Haynes II Joshua Donato Katie Stinebaugh 《Journal of Map & Geography Libraries》2015,11(2):180-206
The Terra Populus project (TerraPop) addresses a variety of data management, curation, and preservation challenges with respect to spatiotemporal population and environmental data. In this article, we describe our approaches to these challenges, with a particular focus on geospatial data workflows and associated provenance metadata. The goal of TerraPop is to enable research, learning, and policy analysis by providing integrated spatiotemporal data describing people and their environment. To do so, TerraPop is assembling a globe-spanning and temporally extensive collection of high-quality population and environmental data, ensuring good documentation, and developing a Web-based data access system that enables users to assemble customized integrated data sets drawing on a variety of data sources and formats. We describe TerraPop's collection strategies, detail the geospatial workflows involved in preparing data for ingest into the project database and those used to transform data across formats for dissemination, and discuss the system used to capture and manage provenance metadata throughout the project. A key aspect of the project is the development of global current and historical administrative unit boundaries that can be linked to census data. These boundaries serve as the linchpin of TerraPop's data integration strategy, and constitute an important data set in their own right. 相似文献
109.
Joshua F. Lawrence Rebecca Givens Rolland Lee Branum-Martin Catherine E. Snow 《Journal of Education for Students Placed at Risk》2014,19(2):76-97
We tested whether urban middle-school students from mostly low-income homes had improved academic vocabulary when they participated in a freely available vocabulary program, Word Generation (WG). To understand how this program may support students at risk for long-term reading difficulty, we examined treatment interactions with baseline achievement on a state standardized test and also differential effects for students with (n = 398) and without (n = 1,395) individualized education plans (IEPs). Students in this unmatched quasi-experiment (5 WG and 4 comparison schools) completed pre- and postvocabulary assessments during the intervention year. We also retested student vocabulary knowledge after summer vacation and the following spring on 11 target words to construct a longitudinally consistent scaled score across 4 waves of data. Growth models show that students experienced summer setback. Although there were no average underlying differences in growth or differences in summer setback for students by baseline achievement, better readers improved more from program participation. IEP status did not predict differential benefits of program participation, and students with IEPs maintained gains associated with participation in WG; however, participation in the program did not change underlying growth trajectories favoring students who did not have IEPs. 相似文献
110.