• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 350
  • 134
  • 38
  • 33
  • 32
  • 31
  • 16
  • 12
  • 11
  • 10
  • 8
  • 6
  • 6
  • 6
  • 4
  • Tagged with
  • 782
  • 122
  • 89
  • 86
  • 84
  • 73
  • 65
  • 59
  • 53
  • 51
  • 51
  • 50
  • 44
  • 41
  • 40
  • 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.
311

Volume distribution and the geometry of high-dimensional random polytopes

Pivovarov, Peter Unknown Date
No description available.
312

Aspen (Populus tremuloides) root suckering as influenced by log storage, traffic-induced-root wounding, slash accumulation, and soil compaction

Renkema, Kevin N Unknown Date
No description available.
313

Hydraulic Characteristics of Fully Developed Flow in Circular Culverts

Kehler, Nicholas Jon 14 September 2009 (has links)
Throughout the world, particularly in countries such as Canada, water crossings are a significant part of the infrastructure system. Since corrugated metal pipe culverts are an inexpensive choice, as well as hydraulically efficient, they are a very appealing option to designers. To ensure that the natural ecosystem is not adversely affected, culverts must be designed so that throughout the year fish can migrate upstream. Current design regulations are based on the average velocity within the culvert and the prolonged swimming speed of the fish species present. In order to examine the validity of this approach, a physical modeling study was undertaken using a circular CMP culvert. It was found that there is significant cross sectional area below average velocity, and that gravel embedment further increases this area. In addition, a technique was developed that produced very agreeable streamwise velocity predictions over a two dimensional cross section in the developed region.
314

Privacy Protection for Life-log System

Chaudhari, Jayashri S. 01 January 2007 (has links)
Tremendous advances in wearable computing and storage technologies enable us to record not just snapshots of an event but the whole human experience for a long period of time. Such a \life-logandamp;quot; system captures important events as they happen, rather than an after-thought. Such a system has applications in many areas such as law enforcement, personal archives, police questioning, and medicine. Much of the existing eandamp;reg;orts focus on the pattern recognition and information retrieval aspects of the system. On the other hand, the privacy issues raised by such an intrusive system have not received much attention from the research community. The objectives of this research project are two-fold: andamp;macr;rst, to construct a wearable life-log video system, and second, to provide a solution for protecting the identity of the subjects in the video while keeping the video useful. In this thesis work, we designed a portable wearable life-log system that implements audio distortion and face blocking in a real time to protect the privacy of the subjects who are being recorded in life-log video. For audio, our system automatically isolates the subject's speech and distorts it using a pitch- shifting algorithm to conceal the identity. For video, our system uses a real-time face detection, tracking and blocking algorithm to obfuscate the faces of the subjects. Extensive experiments have been conducted on interview videos to demonstrate the ability of our system in protecting the identity of the subject while maintaining the usability of the life-log video.
315

A Rejection Technique for Sampling from T-Concave Distributions

Hörmann, Wolfgang January 1994 (has links) (PDF)
A rejection algorithm - called transformed density rejection - that uses a new method for constructing simple hat functions for an unimodal, bounded density $f$ is introduced. It is based on the idea to transform $f$ with a suitable transformation $T$ such that $T(f(x))$ is concave. $f$ is then called $T$-concave and tangents of $T(f(x))$ in the mode and in a point on the left and right side are used to construct a hat function with table-mountain shape. It is possible to give conditions for the optimal choice of these points of contact. With $T=-1/\sqrt(x)$ the method can be used to construct a universal algorithm that is applicable to a large class of unimodal distributions including the normal, beta, gamma and t-distribution. (author's abstract) / Series: Preprint Series / Department of Applied Statistics and Data Processing
316

Identifying barriers to traditional game consumption in First Nation adolescents in remote northern communities in Ontario, Canada

Hlimi, Tina 06 November 2014 (has links)
Objectives: To investigate factors influencing consumption of traditional foods (e.g., wild game, fish) and concerns about environmental contaminants among schoolchildren of the Mushkegowuk Territory First Nations (Moose Factory, Fort Albany, Kashechewan, Attawapiskat, and Peawanuck). Study Design: Cross-sectional data collection from a Web-based Eating Behaviour Questionnaire (WEB-Q). Methods: Schoolchildren in grades 6-12 (n = 262) responded to four of the WEB-Q questions: (1) Do you eat game? (2) How often do you eat game? (3) How concerned are you about the environmental contaminants in the wild game and fish that you eat? (4) I would eat more game if...[ six response options]. Data were collected from 2004-2009. Hierarchical log-linear modelling (LLM) was used for analyses of multi-way frequency data. Results: Of the school children answering the specific questions: 174 consumed game; 95 reported concerns about contaminants in game; and 84 would increase their game consumption if it were more available in their homes. LLM revealed significant differences between communities; schoolchildren in Moose Factory consumed game ???rarely or never??? at greater than expected frequency, and fewer than expected consumed game ???at least once a day.??? Schoolchildren in Kashechewan had greater frequency of daily game consumption and few were concerned about contaminants in game. Using LLM, we found that sex was an insignificant variable and did not affect game consumption frequency or environmental contaminant concern. Conclusion: The decreasing importance of the traditional diet was most evident in Moose Factory, possibly due to its more southerly location relative to the other First Nations examined.
317

Hydraulic Characteristics of Fully Developed Flow in Circular Culverts

Kehler, Nicholas Jon 14 September 2009 (has links)
Throughout the world, particularly in countries such as Canada, water crossings are a significant part of the infrastructure system. Since corrugated metal pipe culverts are an inexpensive choice, as well as hydraulically efficient, they are a very appealing option to designers. To ensure that the natural ecosystem is not adversely affected, culverts must be designed so that throughout the year fish can migrate upstream. Current design regulations are based on the average velocity within the culvert and the prolonged swimming speed of the fish species present. In order to examine the validity of this approach, a physical modeling study was undertaken using a circular CMP culvert. It was found that there is significant cross sectional area below average velocity, and that gravel embedment further increases this area. In addition, a technique was developed that produced very agreeable streamwise velocity predictions over a two dimensional cross section in the developed region.
318

Bayesian Analysis of Spatial Point Patterns

Leininger, Thomas Jeffrey January 2014 (has links)
<p>We explore the posterior inference available for Bayesian spatial point process models. In the literature, discussion of such models is usually focused on model fitting and rejecting complete spatial randomness, with model diagnostics and posterior inference often left as an afterthought. Posterior predictive point patterns are shown to be useful in performing model diagnostics and model selection, as well as providing a wide array of posterior model summaries. We prescribe Bayesian residuals and methods for cross-validation and model selection for Poisson processes, log-Gaussian Cox processes, Gibbs processes, and cluster processes. These novel approaches are demonstrated using existing datasets and simulation studies.</p> / Dissertation
319

Gristhorpe Man: an Early Bronze Age log-coffin burial scientifically defined

Melton, N., Montgomery, Janet A., Knüsel, Christopher J., Batt, Catherine M., Needham, S., Parker Pearson, M., Sheridan, A. January 2010 (has links)
A log-coffin excavated in the early nineteenth century proved to be well enough preserved in the early twenty-first century for the full armoury of modern scientific investigation to give its occupants and contents new identity, new origins and a new date. In many ways the interpretation is much the same as before: a local big man buried looking out to sea. Modern analytical techniques can create a person more real, more human and more securely anchored in history. This research team shows how.
320

Automatic Pose and Position Estimation by Using Spiral Codes

Albayrak, Aras January 2014 (has links)
This master thesis is about providing the implementation of synthesis, detection of spiral symbols and estimating the pan/tilt angle and position by using camera calibration. The focus is however on the latter, the estimation of parameters of localization. Spiral symbols are used to be able to give an object an identity as well as to locate it. Due to the spiral symbol´s characteristic shape, we can use the generalized structure tensor (GST) algorithm which is particularly efficient to detect different members of the spiral family. Once we detect spirals, we know the position and identity parameters of the spirals within an apriori known geometric configuration (on a sheet of paper). In turn, this information can be used to estimate the 3D-position and orientation of the object on which spirals are attached using a camera calibration method.   This thesis provides an insight into how automatic detection of spirals attached on a sheet of paper, and from this, automatic deduction of position and pose parameters of the sheet, can be achieved by using a network camera. GST algorithm has an advantage of running the processes of detection of spirals efficiently w.r.t detection performance and computational resources because it uses a spiral image model well adapted to spiral spatial frequency characteristic. We report results on how detection is affected by zoom parameters of the network camera, as well as by the GST parameters; such as filter size. After all spirals centers are located and identified w.r.t. their twist/bending parameter, a flexible technique for camera calibration, proposed by Zhengyou Zhang implemented in Matlab within the present study, is performed. The performance of the position and pose estimation in 3D is reported. The main conclusion is, we have reasonable surface angle estimations for images which were taken by a WLAN network camera in different conditions such as different illumination and different distances.

Page generated in 0.03 seconds