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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.
51

網際網路瀏覽行為之研究 / Browsing Behaviors on World Wide Web

趙光正 Unknown Date (has links)
This study examined the context of browsing behaviors. According to uses-and gratifications approach, the motives of World Wilde Web (mentioned as WWW later) generate the expectations of the WWW and the other sources, which lead to differential patterns of browsing behaviors. On-line focus groups were performed three times in December 1999 and January 2000. The criterion used when we choose the respondents of the focus group is that they should have experienced in Internet at least one year. The purpose of the focus groups is to explore the context of browsing. In addition, an on-line survey was undertaken on and . The session of is from March 25, 2000 to April 20, 2000, and the session of is from April 11, 2000 to April 12, 2000. The primary purpose of the survey was to test hypotheses related to browsing motives, browsing strategy motives, and browsing activities. This study found that surfers were segmented into four groups according to the motives of WWW: ritualistic dominant motives, instrumental dominant motives, high motives, and low motives. Besides, the motives of browsing strategies ere probed in this study. Six factors of the motives of browsing strategies were extracted: to increase data completeness, to help awareness of site options, to avoid site redundancy or information duplicate, job factor, no scare at the loss in cyberspace, and to kill time in a high-speed or favorable site. These factors co-operated with browsing skills explaining medium to low variance of the browsing behaviors.
52

The impacts of sambar (Cervus unicolor) in the Yarra Ranges National Park

Bennett, Ami January 2008 (has links)
Internationally, the impacts of deer have been widely studied, but little work has been conducted in Australia. Sambar (Cervus unicolor Kerr) were introduced to Victoria in the 1860s from Sri Lanka, and have become established throughout eastern Victoria. This study is located in the Yarra Ranges National Park, 100 km north east of Melbourne. The park primarily consists of three protected water catchments that contribute approximately 50% to Melbourne’s water supply. This study was conducted from 2005 to 2008 in the Upper Yarra and O’Shannassy catchments. Large open areas covered by forbs and grasses periodically form adjacent to the water body of the Upper Yarra reservoir. Sambar are frequently observed at the largest of these areas known as The Flats. The impacts of sambar at this locality and in other areas of the catchments were investigated. / Faecal pellet transect surveys determined that sambar occupancy and density was greatest on open flats, lower on forest edges adjacent to open flats (< 250 m), and significantly less in other forested areas of the catchment. Observations of The Flats revealed that hinds were the main demographic class represented, with a mean group size of 39 individuals, and up to 70. This is the largest aggregation of sambar ever reported anywhere in the world, and equates to an approximate density of 200 km-2 at this site. / Selective exclosures effectively differentiated the offtake of forage by sambar from that of native herbivores. Sambar contributed to the majority of offtake at The Flats, and were able to obtain a substantial proportion of their daily food requirements from this source. A culling program began in the Yarra Ranges National Park in May 2008, to reduce the large numbers of deer in the park. The cull reduced the time spent by sambar on The Flats, as determined by faecal pellet accumulation plots, and significantly reduced faecal pellet load and forage offtake. / Sambar significantly decreased relative foliage cover of shiny nematolepis (Nematolepis wilsonii), a threatened understorey tree, through their antler rubbing activities. Thrashing of shiny nematolepis saplings also significantly decreased relative foliage cover, with sambar selecting saplings with a larger stem diameter from those available. Rubbed trees and thrashed saplings experienced damage to, on average, over half the stem circumference. / Selective exclosures allowed differentiation of sambar and native herbivore browsing on forest understoreys. Browsing by sambar in high densities prevented the vertical growth of plants in the understorey, with branches above 60 cm in height most commonly browsed. Plants in the understorey were more frequently and intensely browsed in areas of high sambar density. Three species were browsed to a significantly greater extent by sambar than native herbivores: hazel pomaderris (Pomaderris aspera), prickly tea-tree (Leptospermum continentale) and prickly bush-pea, (Pultenaea juniperina). Sambar significantly reduced plant biomass in forest understoreys where they occur in high densities. / The presence of large, open herb-rich areas drives the high local densities and associated impacts of sambar within the Yarra Ranges National Park. Future areas of research are identified and management recommendations are outlined. A sustained culling program appears to be the only practical option to reduce sambar density and impacts at this locality.
53

Dynamic Categorization: What We Can Learn from the Emergent Arrangement of Physical Artifacts in Libraries

Krauss, Armin Martin 07 January 2011 (has links)
Radio frequency identification (RFID) is a technology used in many applications for the identification of objects. This thesis presents a concept of how libraries could use RFID technology to locate physical items within the library. The ability to locate items within the library changes the way users interact with physical material, creates new ways of user collaboration, and influences the ability to browse the shelves for physical items. Several implementation scenarios are presented in detail and implications on collaboration and browsing are analyzed.
54

Dynamic Categorization: What We Can Learn from the Emergent Arrangement of Physical Artifacts in Libraries

Krauss, Armin Martin 07 January 2011 (has links)
Radio frequency identification (RFID) is a technology used in many applications for the identification of objects. This thesis presents a concept of how libraries could use RFID technology to locate physical items within the library. The ability to locate items within the library changes the way users interact with physical material, creates new ways of user collaboration, and influences the ability to browse the shelves for physical items. Several implementation scenarios are presented in detail and implications on collaboration and browsing are analyzed.
55

Forensic analysis of the ESE database in Internet Explorer 10

Malmström, Bonnie, Teveldal, Philip January 2013 (has links)
With Internet Explorer 10, Microsoft changed the way of storing web related information. Instead of the old index.dat files, Internet Explorer 10 uses an ESE database called WebCacheV01.dat to maintain its web cache, history and cookies. This database contains a wealth of information that can be of great interest to a forensic investigator. This thesis explores the structure of the new database, what information it contains, how it behaves in different situations, and also shows that it is possible to recover deleted database records – even when the InPrivate browsing mode has been used.
56

Indexing presentations using multiple media streams

Ruddarraju, Ravikrishna 15 August 2006 (has links)
This thesis presents novel techniques to index multiple media streams in a digi- tally captured presentation. These media streams are related by the common content in a presentation. We use relevance curves to represent these relationships. These relevance curves are generated by using a mix of text processing techniques and distance measures for sparse vocabularies. These techniques are used to automatically detect slide boundaries in a presentation. Accuracy of detecting these boundaries is evaluated as a function of word error rates.
57

Toward better server-side Web security

Son, Sooel 25 June 2014 (has links)
Server-side Web applications are constantly exposed to new threats as new technologies emerge. For instance, forced browsing attacks exploit incomplete access-control enforcement to perform security-sensitive operations (such as database writes without proper permission) by invoking unintended program entry points. SQL command injection attacks (SQLCIA) have evolved into NoSQL command injection attacks targeting the increasingly popular NoSQL databases. They may expose internal data, bypass authentication or violate security and privacy properties. Preventing such Web attacks demands defensive programming techniques that require repetitive and error-prone manual coding and auditing. This dissertation presents three methods for improving the security of server-side Web applications against forced browsing and SQL/NoSQL command injection attacks. The first method finds incomplete access-control enforcement. It statically identifies access-control logic that mediates security-sensitive operations and finds missing access-control checks without an a priori specification of an access-control policy. Second, we design, implement and evaluate a static analysis and program transformation tool that finds access-control errors of omission and produces candidate repairs. Our third method dynamically identifies SQL/NoSQL command injection attacks. It computes shadow values for tracking user-injected values and then parses a shadow value along with the original database query in tandem with its shadow value to identify whether user-injected parts serve as code. Remediating Web vulnerabilities and blocking Web attacks are essential for improving Web application security. Automated security tools help developers remediate Web vulnerabilities and block Web attacks while minimizing error-prone human factors. This dissertation describes automated tools implementing the proposed ideas and explores their applications to real-world server-side Web applications. Automated security tools are effective for identifying server-side Web application security holes and a promising direction toward better server-side Web security. / text
58

Respone of tree-ring width and regeneration in conifer forests of Mongolia to climate warming and land use

Mookhor, Khishigjargal 15 July 2013 (has links)
No description available.
59

Determining the ecological mechanisms of forest encroachment within the aspen parkland of western Canada

Lastra, Rod 02 September 2011 (has links)
The encroachment of woody species into grassland and savanna ecosystems has been well document since the early 1800s. Within the parkland ecoregion of western Canada, trembling aspen (Populus tremuloides Michx.) has been one of the key tree species increasing in dominance. Aspen encroachment is best explained not by single mechanism, but rather by a number of interacting ecological factors. In this study I examined the ecological consequences of the clonal biology in aspen as a means to explain persistence and observed tree-grass ratios within grassland savannas of western Canada. Results suggest that aspen stands cycle between a “stable” phase characterized by a dense mature canopy, and an “unstable” phase characterized by canopy breakup and increased regeneration from root suckers. It is during this unstable phase that clonal encroachment is likely to occur. Within these mature stands, different-aged ramets promote persistence by maximizing developmental variation. Such a mechanism overcomes the functional phenotypic uniformity of ramets within a single age-structured stand. Results from my study indicate that physiological integration is beneficial to the growth and survivorship of regenerating and encroaching aspen ramets. My results also suggest that the benefits of physiological integration are greatest in more stressful environments, and in recently established post-fire ramets. Finally, the consequences of variation in adaptive ecological relevant traits among individuals was examined by determining differences in vigor among aspen clones in relation to the production of secondary compounds (phenolic glycosides). My results demonstrate a high degree of variation in leaf phenolic glycosides production among clones. A significant amount of this variation was accounted for by differences in clone vigor (within population: individual susceptibility hypothesis), with a smaller amount related to environmental differences (among populations). In all instances, vigorous clones were significantly higher in levels of phenolic glycosides compared with dieback clones, suggesting that some individuals may be predisposed to undergo density-independent mortality. This has important ecological implications, because it implies that one of the key mechanisms regulating population dynamics, community interactions and biodiversity may be related to intrinsic adaptive differences in susceptibility among individuals.
60

Determining the ecological mechanisms of forest encroachment within the aspen parkland of western Canada

Lastra, Rod 02 September 2011 (has links)
The encroachment of woody species into grassland and savanna ecosystems has been well document since the early 1800s. Within the parkland ecoregion of western Canada, trembling aspen (Populus tremuloides Michx.) has been one of the key tree species increasing in dominance. Aspen encroachment is best explained not by single mechanism, but rather by a number of interacting ecological factors. In this study I examined the ecological consequences of the clonal biology in aspen as a means to explain persistence and observed tree-grass ratios within grassland savannas of western Canada. Results suggest that aspen stands cycle between a “stable” phase characterized by a dense mature canopy, and an “unstable” phase characterized by canopy breakup and increased regeneration from root suckers. It is during this unstable phase that clonal encroachment is likely to occur. Within these mature stands, different-aged ramets promote persistence by maximizing developmental variation. Such a mechanism overcomes the functional phenotypic uniformity of ramets within a single age-structured stand. Results from my study indicate that physiological integration is beneficial to the growth and survivorship of regenerating and encroaching aspen ramets. My results also suggest that the benefits of physiological integration are greatest in more stressful environments, and in recently established post-fire ramets. Finally, the consequences of variation in adaptive ecological relevant traits among individuals was examined by determining differences in vigor among aspen clones in relation to the production of secondary compounds (phenolic glycosides). My results demonstrate a high degree of variation in leaf phenolic glycosides production among clones. A significant amount of this variation was accounted for by differences in clone vigor (within population: individual susceptibility hypothesis), with a smaller amount related to environmental differences (among populations). In all instances, vigorous clones were significantly higher in levels of phenolic glycosides compared with dieback clones, suggesting that some individuals may be predisposed to undergo density-independent mortality. This has important ecological implications, because it implies that one of the key mechanisms regulating population dynamics, community interactions and biodiversity may be related to intrinsic adaptive differences in susceptibility among individuals.

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