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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
411

Elementary school educators' assumptions on the identification of students who are gifted and talented

Gaudet, Danielle Yvette 25 June 2008
The purpose of this study was to investigate the assumptions held by Saskatchewan educators in the identification of students who are gifted and talented. Elementary school educators from Kindergarten to grade 8 were approached to participate in this study, and were asked to complete a 20-item survey that examined educators assumptions relating to the identification of students who are gifted and talented (Brown, Renzulli, Gubbins, Siegle, Zhang, & Chen, 2005). Findings suggest that there are differences in assumptions relating to the identification of students who are gifted and talented not only between educators of various grades, but also between those educators in different classroom environments (i.e., dedicated, multiple, or no classroom). Educators roles in the classroom include engaging students in authentic assessment procedures, which take into account students day-to-day learning and progress.
412

The Identity Myth: Constructing the Face in Technologies of Citizenship

Ferenbok, Joseph 13 April 2010 (has links)
Over the last century, images of faces have become integral components of many institutional identification systems. A driver’s licence, a passport and often even a health care card, all usually feature prominently images representing the face of their bearer as part of the mechanism for linking real-world bodies to institutional records. Increasingly the production, distribution and inspection of these documents is becoming computer-mediated. As photo ID documents become ‘enhanced’ by computerization, the design challenges and compromises become increasingly coded in the hierarchy of gazes aimed at individual faces and their technologically mediated surrogates. In Western visual culture, representations of faces have been incorporated into identity documents since the 15th century when Renaissance portraits were first used to visually and legally establish the social and institutional positions of particular individuals. However, it was not until the 20th century that official identity documents and infrastructures began to include photographic representations of individual faces. This work explores photo ID documents within the context of “the face,”—a theoretical model for understanding relationships of power coded using representations of particular human faces as tokens of identity. “The face” is a product of mythology for linking ideas of stable identity with images of particular human beings. This thesis extends the panoptic model of the body and contributes to the understanding of changes posed by computerization to the norms of constructing institutional identity and interaction based on surrogates of faces. The exploration is guided by four key research questions: What is “the face”? How does it work? What are its origins (or mythologies)? And how is “the face” being transformed through digitization? To address these questions this thesis weaves ideas from theorists including Foucault, Deleuze and Lyon to explore the rise of “the face” as a strategy for governing, sorting, and classifying members of constituent populations. The work re-examines the techno-political value of captured faces as identity data and by tracing the cultural and techno-political genealogies tying faces to ideas of stable institutional identities this thesis demonstrates face-based identity practices are being improvised and reconfigured by computerization and why these practices are significant for understanding the changing norms of interaction between individuals and institutions.
413

Daphne Sudden Death Syndrome (DSDS): pathogen identification, characterization and screening for disease resistance

Noshad, David 05 1900 (has links)
Daphne is a widely dispersed genus with large variation in morphology, native habitats, and use. Unfortunately, broader acceptance of Daphne in the ornamental trade has been limited due to Daphne Sudden Death Syndrome (DSDS), a disease that kills the plant without warning. The results of this research identified Thielaviopsis basicola (Berk. etBr.) Ferr. as the causal agent for this disease. Pure cultures of the pathogen were developed and used in a germ plasm screen. To evaluate Daphne germ plasm in vitro, species-specific protocols were developed that alleviated two common problems in Daphne micropropagation, browning and hyperhydricity. Optimizing the concentrations of both PGRs and charcoal was able to control these problems. Selected species were evaluated for resistance against Thielavipsis basicola in both, in vivo and in vitro, conditions. The results of both methods displayed a strong correlation and indicated significant differences among the taxa. However, there were differences in disease progression rates. Typically, the in vitro challenge produced a comparable level of disease as the in vivo challenge but in two to three weeks less time. Across both screening methods, the most resistant species evaluated were D. tangutica and D. retusa, while D. cneroum was the most susceptible. Based on ITS sequences, phylogenetic relationships among selected Daphne species were established and associated with their resistance against T basicola. The phylogeny indicated that Daphne is possibly a monophyletic group. However, placement of D.genkwa remained problematic. The analysis of ITS sequences data resulted in a parsimony consensus tree with two well-supported major clades and one Glade with less support. In general, the evolutionary tree for resistance, inferred from the phylogenetic data and the results of the screening project, indicate that resistance is a derived character and that plants recently evolved this ability.
414

Next Generation RFID Randomization Protocol

LaValley, Jason 06 December 2011 (has links)
Radio Frequency IDentification (RFID) is a wireless communications technology which allows companies to secure their assets and increase the portability of information. This research was motivated by the increased commercial use of RFID technology. Existing security protocols with high levels of security have high computation requirements, and less intensive protocols can allow a tag to be tracked. The techniques proposed in this thesis result in the increase of ciphertexts available without a significant increase in processing power or storage requirements. The addition of random inputs to the generation of ciphertexts will increase the number of possible results without requiring a more advanced encryption algorithm or an increased number of stored encryption keys. Four methods of altering the plaintext/ciphertext pair (random block, set pattern, random pattern, and indexed placement) are analyzed to determine the effectiveness of each method. The number of ciphertexts generated, generation time, and generation errors were recorded to determine which of the four proposed methods would be the most beneficial in a RFID system. The comparison of these method characteristics determined that the set pattern placement method provided the best solution. The thesis also discusses how RFID transmissions appear to attackers and explains how the random inputs reduce effectiveness of current system attacks. In addition to improving the anonymity of RFID tag transmissions, the concept of authenticating random inputs is also introduced in this thesis. These methods help prevent an adversary from easily associating a tag with its transmissions, thus increasing the security of the RFID system.
415

Assessing Entrepreneurial Orientation in the Instructional Setting: Testing a Model

Cachon, Jean-Charles, Cotton, Barry January 1987 (has links)
This paper reports the initial investigation of the possibility of identifying an entrepreneurial orientation among subjects who have undergone a venture identification and creation experience. The basis for the development of the measurement model were characteristics identified from the literature as forming the emerging entrepreneur paradigm. The purpose of the longitudinal research is to establish a methodology for the identification of people possessing entrepreneurial potential and whose further development could then be encouraged. Variables in the model which proved to be predictors of entrepreneurial orientation included Locus of Control which is a very strong entrepreneurial orientation. Attitude Towards Risk proved to be a predictor of a general interest in entrepreneurial activities, supporting findings in the literature. Significantly, a new variable was identified out of scales measuring Personal Objectives (PO). A strong link was found between the nature of personal skill advantages, objectives and interests fulfilled during the experimental project and entrepreneurial orientation. SOMMAIRE Cet article rend compte de travaux initiaux sur la determination de l'esprit d'entreprise de sujets qui ont fait une experience supposant la prise de risques et un recours à la création. Le modèle de mesure a été élaboré à partir de caractéristiques trouvées dans les livres pertinents sur ce qui constitue l'archetype de l'entrepreneur en puissance. La recherche longitudinale vise a trouver des méthodes pour déterminer les personnes douées d'un esprit d'entreprise dont on peut favoriser le développement. Parmi les variables du modèle qui se sont révélées être des indices d'esprit d'entreprise, figure le "lieu géométrique d'autorité", un critère très important. II s'est avéré que l'attitude face au risque était un indice d'intérêt général pour les activités reliées à l'esprit d'entreprise, ce qui corrobore les constatations des écrits sur la question. Une nouvelle variable a été dégagée des échelles qui mesurent les objectifs personnels(OP). On a, en effet, découvert un lien étroit entre les aptitudes, les objectifs et les intérêts personnels concrétisés au cours du projet expérimental, d'une part, et l'esprit d'entreprise, d'autre part. / This research was funded in part by a Social Sciences & Humanities Research Council of Canada block grant.
416

A Rock Borehole Packer System for Identifying Hydraulically Active Fractures Under Natural Gradient Flow

Kroeker, Ryan 21 May 2008 (has links)
To improve capabilities for understanding and predicting contaminant migration in fractured rock there is need for better field methods to identify the fractures that have active groundwater flow. Current methods have limitations, for example, borehole geophysical imaging, such as acoustic and optical televiewing, identifies fractures appearing on borehole walls but cannot sense groundwater flow. Borehole hydraulic tests determine the transmissivity of fractured zones under conditions altered by the presence of the borehole and its testing and not under natural flow conditions. The natural flow conditions are important because they govern contaminant transport in the whole flow system. Furthermore, conventional tracer tests are used to identify flow in fractures, but these too are typically done under imposed rather than ambient (natural) hydraulic conditions. High resolution fluid temperature logging in lined boreholes can identify some of the hydraulically active fractures, but this method lacks the sensitivity needed to indicate ambient flow in each individual fracture. This thesis presents a new method aimed at determining whether or not any particular fracture targeted for borehole measurement has substantial ambient flow. This method involves a device lowered into an open hole to a target zone where a packer is inflated. This packer has a water-flow-sensitive dyed cotton fabric wrapped around its exterior so that when the packer is inflated, it not only seals the borehole but presses the cotton fabric against the borehole wall. This set-up causes the exact location of hydraulically active fractures at the borehole wall to show up as imprints marked on the fabric. When viewed under black light, individual fracture markings can be seen, and the distribution of the hydraulically active fractures is identified. For this new method, a prototype system was developed for use in 10cm diameter wells and was tested first in a conventional slotted well screen in the laboratory and then in a simulated fracture (slotted) PVC pipe installed in a sandy aquifer where groundwater flow rates are well understood. From a large number of fabric/dye combinations tested in the laboratory, it was found that cotton dyed with a particular food grade additive provides the best fracture markings by far. The prototype system uses the double-acting packer system originally developed by Solinst Canada, and this novel packer design provides ease of use and flexibility for configuring multiple packers on a single pipe. This prototype system is now ready for the first field trials in a fractured dolostone borehole in Guelph, ON. While the ability of the device to identify active fractures as effectively as it has in the slotted casing trials may be reduced by the interaction of the dye with the porous rock matrix, it is anticipated that this new system for identifying hydraulically active fractures under resealed borehole flow conditions (resealing brings flow back to ambient conditions) will be useful in its own right in fractured rock investigations. This device also represents the first step in the creation of a more elaborate device to measure both the groundwater flux and the contaminant flux within plumes in fractured rock.
417

RFIDs användning i produktionsprocesser : en studie bland operatörer på Lear Corporation

Andersson, Jessica, Larsson, Stina, Jendesand, Gunilla January 2005 (has links)
No description available.
418

Linear and Nonlinear Identification of Solid Fuel Furnace

Gransten, Johan January 2005 (has links)
The aim of this thesis is to develop the knowledge about nonlinear and/or adaptive solid fuel boiler control at Vattenfall Utveckling AB. The aim is also to make a study of implemented and published control strategies. A solid fuel boiler is a large-scale heat (and power) generating plant. The Idbäcken boiler studied in this work, is a one hundred MW furnace mainly fired with wood chips. The control system consists of several linear PID controllers working together, and the furnace is a nonlinear system. That, and the fact that the fuel-flow is not monitored, are the main reasons for the control problems. The system fluctuates periodically and the CO outlets sometimes rise high above the permitted level. There is little work done in the area of advanced boiler control, but some interesting approaches are described in scientific articles. MPC (Model Predictive Control), nonlinear system identification using ANN (Artificial Neural Network), fuzzy logic, Hµ loop shaping and MIMO (Multiple Input Multiple Output) PID tuning methods have been tested with good results. Both linear and nonlinear system identification is performed in the thesis. The linear models are able to explain about forty percent of the system behavior and the nonlinear models explain about sixty to eighty percent. The main result is that nonlinear models improve the performance and that there are considerable disturbances complicating the identification. Another identification issue was the feedback during the data collection.
419

Unsupervised Learning for Plant Recognition

Jelacic, Mersad January 2006 (has links)
Six methods are used for clustering data containing two different objects: sugar-beet plants and weed. These objects are described by 19 different features, i.e. shape and color features. There is also information about the distance between sugar-beet plants that is used for labeling clusters. The methods that are evaluated: k-means, k-medoids, hierarchical clustering, competitive learning, self-organizing maps and fuzzy c-means. After using the methods on plant data, clusters are formed. The clusters are labeled with three different proposed methods: expert, database and context method. Expert method is using a human for giving initial cluster centers that are labeled. The database method is using a database as an expert that provides initial cluster centers. The context method is using information about the environment, which is the distance between sugar-beet plants, for labeling the clusters. The algorithms that were tested, with the lowest achieved corresponding error, are: k-means (3.3%), k-medoids (3.8%), hierarchical clustering (5.3%), competitive learning (6.8%), self- organizing maps (4.9%) and fuzzy c-means (7.9%). Three different datasets were used and the lowest error on dataset0 is 3.3%, compared to supervised learning methods where it is 3%. For dataset1 the error is 18.7% and for dataset2 it is 5.8%. Compared to supervised methods, the error on dataset1 is 11% and for dataset2 it is 5.1%. The high error rate on dataset1 is due to the samples are not very well separated in different clusters. The features from dataset1 are extracted from lower resolution on images than the other datasets, and another difference between the datasets are the sugar-beet plants that are in different growth stages. The performance of the three methods for labeling clusters is: expert method (6.8% as the lowest error achieved), database method (3.7%) and context method (6.8%). These results show the clustering results by competitive learning where the real error is 6.8%. Unsupervised-learning methods for clustering can very well be used for plant identification. Because the samples are not classified, an automatic labeling technique must be used if plants are to be identified. The three proposed techniques can be used for automatic labeling of plants.
420

A Rock Borehole Packer System for Identifying Hydraulically Active Fractures Under Natural Gradient Flow

Kroeker, Ryan 21 May 2008 (has links)
To improve capabilities for understanding and predicting contaminant migration in fractured rock there is need for better field methods to identify the fractures that have active groundwater flow. Current methods have limitations, for example, borehole geophysical imaging, such as acoustic and optical televiewing, identifies fractures appearing on borehole walls but cannot sense groundwater flow. Borehole hydraulic tests determine the transmissivity of fractured zones under conditions altered by the presence of the borehole and its testing and not under natural flow conditions. The natural flow conditions are important because they govern contaminant transport in the whole flow system. Furthermore, conventional tracer tests are used to identify flow in fractures, but these too are typically done under imposed rather than ambient (natural) hydraulic conditions. High resolution fluid temperature logging in lined boreholes can identify some of the hydraulically active fractures, but this method lacks the sensitivity needed to indicate ambient flow in each individual fracture. This thesis presents a new method aimed at determining whether or not any particular fracture targeted for borehole measurement has substantial ambient flow. This method involves a device lowered into an open hole to a target zone where a packer is inflated. This packer has a water-flow-sensitive dyed cotton fabric wrapped around its exterior so that when the packer is inflated, it not only seals the borehole but presses the cotton fabric against the borehole wall. This set-up causes the exact location of hydraulically active fractures at the borehole wall to show up as imprints marked on the fabric. When viewed under black light, individual fracture markings can be seen, and the distribution of the hydraulically active fractures is identified. For this new method, a prototype system was developed for use in 10cm diameter wells and was tested first in a conventional slotted well screen in the laboratory and then in a simulated fracture (slotted) PVC pipe installed in a sandy aquifer where groundwater flow rates are well understood. From a large number of fabric/dye combinations tested in the laboratory, it was found that cotton dyed with a particular food grade additive provides the best fracture markings by far. The prototype system uses the double-acting packer system originally developed by Solinst Canada, and this novel packer design provides ease of use and flexibility for configuring multiple packers on a single pipe. This prototype system is now ready for the first field trials in a fractured dolostone borehole in Guelph, ON. While the ability of the device to identify active fractures as effectively as it has in the slotted casing trials may be reduced by the interaction of the dye with the porous rock matrix, it is anticipated that this new system for identifying hydraulically active fractures under resealed borehole flow conditions (resealing brings flow back to ambient conditions) will be useful in its own right in fractured rock investigations. This device also represents the first step in the creation of a more elaborate device to measure both the groundwater flux and the contaminant flux within plumes in fractured rock.

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