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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.
61

Temporal data mining : algorithms, language and system for temporal association rules

Chen, Xiaodong January 1999 (has links)
Studies on data mining are being pursued in many different research areas, such as Machine Learning, Statistics, and Databases. The work presented in this thesis is based on the database perspective of data mining. The main focuses are on the temporal aspects of data mining problems, especially association rule discovery, and issues on the integration of data mining and database systems. Firstly, a theoretical framework for temporal data mining is proposed in this thesis. Within this framework, not only potential patterns but also temporal features associated with the patterns are expected to be discovered. Calendar time expressions are suggested to represent temporal features and the minimum frequency of patterns is introduced as a new threshold in the model of temporal data mining. The framework also emphasises the necessary components to support temporal data mining tasks. As a specialisation of the proposed framework, the problem of mining temporal association rules is investigated. The methodology adopted in this thesis is eventually discovering potential temporal rules by alternatively using special search techniques for various restricted problems in an interactive and iterative process. Three forms of interesting mining tasks for temporal association rules with certain constraints are identified. These tasks are the discovery of valid time periods of association rules, the discovery of periodicities of association rules, and the discovery of association rules with temporal features. The search techniques and algorithms for those individual tasks are developed and presented in this thesis. Finally, an integrated query and mining system (IQMS) is presented in this thesis, covering the description of an interactive query and mining interface (IQMI) supplied by the IQMS system, the presentation of an SQL-like temporal mining language (TML) with the ability to express various data mining tasks for temporal association rules, and the suggestion of an IQMI-based interactive data mining process. The implementation of this system demonstrates an alternative approach for the integration of the DBMS and data mining functions.
62

The effects of graduated stimulus change on learning efficiency in a visual discrimination task

Corns, David Allan January 1990 (has links)
The investigation examined differences in learning efficiency produced by two different methods of discrimination training among regular placement fifth-grade pupils. It was designed to explore possible between-group differences in rate of learning, length of training, mastery rate, recall of learning, and task persistence following training. The experiment consisted of training, an interference task, and a concluding posttest. Two independent groups were formed by random assignment of subjects. The experimental group began training with graduated stimulus change trials--that is, subjects were presented with a succession of three visual discrimination tasks consisting of six trials per task designed to teach correct responding before incorrect alternatives were gradually introduced. Control subjects did not receive graduated stimulus change trials. Instead, they began each task in the training phase with more complex discriminations at trial seven. Pennies were used for reinforcement of correct choices in each group; incorrect selection resulted in no reinforcer delivery. Both groups were then administered a brief exercise designed to inhibit the recall of acquired discriminations. All subjects concluded with a 54-item posttest consisting of intermingled trials from the three-task training phase. The first 21 items were considered mandatory, but the final 33 were optional (i.e., subjects were instructed to complete as many items as they wished and informed that each correct selection earned a penny). Results indicated that graduated stimulus change (GSC) learners committed significantly fewer errors learning the discriminations and mastered significantly more of the training tasks presented than did trial-and-error learners. There was no significant difference between the two groups in the length of training nor in the degree of persistence during posttest voluntary responding. GSC subjects also committed significantly fewer errors on recall than controls although the degree of absolute forgetting in each group was not significantly different. The findings suggest that regular placement, "easy-to-teach" pupils can profit from GSC programming in several important ways. Without lengthening the training process, stimulus control methodologies can render instruction more efficient than trial-and-error procedures for nonimpaired learners. The need is apparent for further experimental research on the application of errorless discrimination procedures to other areas and levels of education. / Department of Educational Psychology
63

The development and application of heuristic techniques for the data mining task of nugget discovery

Iglesia, Beatriz de la January 2001 (has links)
No description available.
64

Multi-retransmission Route Discovery Schemes for Ad Hoc Wireless Network with a Realistic Physical Layer

Jin, Xiangyang 28 September 2011 (has links)
During the route discovery process, each node receiving the route request packet (RReq) will retransmit it exactly once. A distant neighbor may accidentally receive/loose the only RReq and use it to announce a new route, although that link is inferior/superior for route reply packets (RRep) or actual message routing. Overall, the constructed route may be far from the optimal. All existing route discovery schemes (including DSR/AODV) apply retransmission during route discovery exactly once (1R). Based on a realistic physical layer model, we propose two new route discovery schemes: n-retransmission (nR, retransmitting exactly n times) and n-retransmission c-reception (ncRR), retransmitting until we either reach a total of n own retransmissions or c copies from neighbors are heard. We compare our two new scheme with the traditional one, under otherwise identical conditions (same metric, same packet reception probability on each link) and the same choices about possibly retransmitting again upon discovering a better route (R+) or discarding it (R1), generating route reply packet for every received RRep (B*), or for first and better discovered routes only (B2), and retransmitting RRep exactly once (A1), up to a maximum of three times (A3), or optimally u times decided by link quality (Au). Experimental results show that the proposed ncRR scheme (for n=2 and c=3 or c=4) achieves the best tradeoff between quality of route, success rate and message overhead in the route discovery process, followed by the nR scheme, and both of them are superior to the existing traditional schemes.
65

Discovery processes in designing

Murty, Paul January 2007 (has links)
PhD / This thesis describes an interview study of forty five professionally accomplished male and female designers and architects. The study considers how each respondent designs and makes discoveries throughout conceptual design. How they start designing, what they attempt to achieve, the means they employ, how they cope with getting stuck, their breakthroughs and discoveries and the circumstances of these experiences, are the main ingredients of the study. The aim of the research is to estimate the extent to which designing may be regarded as an insightful activity, by investigating experiences of discoveries as reported by the respondents. Throughout the thesis, discoveries or ideas occurring to respondents when they are not actively designing, an apparent outcome of a latent designing or preparation activity, are referred to as cold discoveries. This label is used to distinguish these discoveries from discoveries that emerge in the run of play, when individuals are actively designing. The latter are referred to as hot discoveries. The relative insightfulness of hot and cold discoveries is also investigated. In general, the evidence from the research suggests that designing is significantly insightful. Most respondents (39:45) reported experiences of insights that have contributed to their designing. In addition there is strong evidence that cold discoveries are considerably more important, both quantitatively and qualitatively, than is currently recognized. More than half of the respondents (25:45) reported the experience of cold discoveries, many after disengaging from designing, when they had been stuck. Being stuck means they were experiencing frustration, or had recognised they were not making satisfactory progress in attempts to resolve some aspect of conceptual design. Typically these respondents reported experiencing discoveries while doing other work, performing some physical activity, resting, or very soon after resuming work. They had elected to let ideas come to them, rather than persist in searching and this strategy was successful. Moreover, many respondents (10:45) described positive attributes of cold discoveries using terms such as stronger, more potent, or pushes boundaries, which suggest their cold discoveries are more insightful than their hot discoveries. Many respondents associated their cold discoveries with mental activities such as incubation, a concept identified by Gestalt theorists nearly a century ago. They used a range of informal terms, such as ideas ticking over, or percolating away. These apparently uncontrolled mental experiences, which I refer to generically as latent preparation, varied from one respondent to another in when, where and how they occurred. Latent preparation or its outcomes, in the form of interruptive thoughts, apparently takes place at any time and during different states of consciousness and attentiveness. It appears to be, at different times, unplanned, unintentional, undirected, unnoticed, or unconscious, in combinations, not necessarily all at once. It is clearly not only an unconscious process. This suggests one, or more of the following; 1) that incubation is only a component of latent preparation, or 2) that the conventional view of incubation, as an unconscious process, does not adequately account for the range of insightful experiences of mentally productive people, such as designers, or 3) that the old issue of whether incubation is a conscious, or an unconscious process, is not vital to a systematic investigation of insightful discovery. The thesis concludes by considering prospects for further research and how the research outcomes could influence education. Apart from the findings already described, statements by the respondents about personal attributes, designing, coping with being stuck and discoveries, were wide ranging, resourceful and down-to-earth, suggesting there are many ways for individuals to become proficient, creative designers at the high end of their profession. A major implication for future research is that latent preparation may be found as readily among highly motivated and skilled individuals in other occupations unrelated to architecture or designing. The evidence of the research so far suggests there is much to be learned about latent preparation that can be usefully applied, for the benefit of individuals aiming to be designers, or simply wanting to become more adept at intervening, transforming and managing unexpected and novel situations of any kind.
66

Enhancing visual arts instruction through technology : how the integration of Discovery Education's United Streaming Videos and the interactive SMART Board is changing instruction in the art room /

Theriault, Shelli, January 2007 (has links) (PDF)
Thesis (M.S.) -- Central Connecticut State University, 2007. / Thesis advisor: Cora Marshall. "... in partial fulfillment of the requirements for the degree of Master of Science in Art Education." Includes bibliographical references (leaves 77-80). Also available via the World Wide Web.
67

Developing a proactive framework for e-discovery compliance

Wallner, Gerald L. January 2008 (has links) (PDF)
Thesis (M.S.C.I.T.)--Regis University, Denver, Colo., 2008. / Title from PDF title page (viewed on June 10, 2008). Includes bibliographical references.
68

The sustainability and development of Hong Kong's land transport system /

Flint, Reuben David. January 1999 (has links)
Thesis (M.A.)--University of Hong Kong, 1999. / Includes bibliographical references (leaves 112-114).
69

Connecting school science and students' everyday lives

Tsurusaki, Blakely Katelin. January 2008 (has links)
Thesis (Ph. D.)--Michigan State University. Dept. of Teacher Education, 2008. / Title from PDF t.p. (viewed Aug. 17, 2009). Includes bibliographical references (p. 186-190). Also issued in print.
70

The sustainability and development of Hong Kong's land transport system

Flint, Reuben David. January 1999 (has links)
Thesis (M.A.)--University of Hong Kong, 1999. / Includes bibliographical references (leaves 112-114). Also available in print.

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