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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.
81

Monochromatic UV absorbance histories of unburned gases in a spark ignition engine

Quader, Ather A. January 1969 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1969. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
82

Theoretical investigation of a laser triggered spark gap

Worts, Eric. January 2005 (has links)
Thesis (M.S.)--University of Missouri-Columbia, 2005. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (January 11, 2007) Includes bibliographical references.
83

An experimental and computational investigation of dielectrics for use in quarter wave coaxial cavity resonators

Lowery, Andrew D. January 2006 (has links)
Thesis (M.S.)--West Virginia University, 2006. / Title from document title page. Document formatted into pages; contains xii, 153 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 133-135).
84

The laser triggered spark gap

Khan, Shaukat Hameed January 1968 (has links)
No description available.
85

Measurement of lubricant film thickness in reciprocating engines

Duszynski, Marek January 1999 (has links)
No description available.
86

Swirling combustion of premixed gaseous reactants in a short cylindrical chamber

Pierik, Ronald Jay January 1987 (has links)
The effects of swirl and spark location on combustion duration were studied in a constant volume cylindrical chamber of length-to-diameter ratio of 0.5. A chemically balanced methane-air mixture was swirled up to 628 radians per second by tangential injection. The chamber was closed by a valve before ignition by a spark gap of variable location and electrode geometry. The burning duration, indicated by repeated measurements of combustion pressure rise, was found to be a strong function of swirl intensity and spark location. Increased swirl resulted in decreased burning duration; mid-radius ignition location combined with high swirl resulted in the shortest combustion durations. Spark gap was found to have an important effect on the standard deviation of the burning duration, especially with high swirl. Various "flame holders" were installed to achieve shorter burning durations and lower cyclic variation. Results indicated that the best ignition source geometry was an unshielded, low-drag probe. This gave the least burning durations and the least cyclic variation at the higher swirl values. / Applied Science, Faculty of / Mechanical Engineering, Department of / Graduate
87

The analysis of trace impurities in uranium compounds using spark-source mass spectrometry

Hudson-Lamb, David Charles January 1991 (has links)
Please read the abstract in the dissertation. / Dissertation (MSc)--University of Pretoria, 1991. / gm2014 / Chemistry / unrestricted
88

Nástroje a metódy pre spracovanie veľkého objemu dát zaznamenaného z dátové zbernice lietadla

Tonhajzer, Tomáš January 2017 (has links)
This thesis deals with methods and technologies for storing and processing big data. Thesis contains design of tools for data storing and creation of system for processing and visualization of big data recorded from airplane data bus.
89

STUDY ON PARALLELIZING PARTICLE FILTERS WITH APPLICATIONS TO TOPIC MODELS

Ding, Erli 01 June 2016 (has links)
No description available.
90

A Large Collection Learning Optimizer Framework

Chakravarty, Saurabh 30 June 2017 (has links)
Content is generated on the web at an increasing rate. The type of content varies from text on a traditional webpage to text on social media portals (e.g., social network sites and microblogs). One such example of social media is the microblogging site Twitter. Twitter is known for its high level of activity during live events, natural disasters, and events of global importance. Challenges with the data in the Twitter universe include the limit of 140 characters on the text length. Because of this limitation, the vocabulary in the Twitter universe includes short abbreviations of sentences, emojis, hashtags, and other non-standard usage. Consequently, traditional text classification techniques are not very effective on tweets. Fortunately, sophisticated text processing techniques like cleaning, lemmatizing, and removal of stop words and special characters will give us clean text which can be further processed to derive richer word semantic and syntactic relationships using state of the art feature selection techniques like Word2Vec. Machine learning techniques, using word features that capture semantic and context relationships, can be of benefit regarding classification accuracy. Improving text classification results on Twitter data would pave the way to categorize tweets relative to human defined real world events. This would allow diverse stakeholder communities to interactively collect, organize, browse, visualize, analyze, summarize, and explore content and sources related to crises, disasters, human rights, inequality, population growth, resiliency, shootings, sustainability, violence, etc. Having the events classified into different categories would help us study causality and correlations among real world events. To check the efficacy of our classifier, we would compare our experimental results with an Association Rules (AR) classifier. This classifier composes its rules around the most discriminating words in the training data. The hierarchy of rules, along with an ability to tune to a support threshold, makes it an effective classifier for scenarios where short text is involved. Traditionally, developing classification systems for these purposes requires a great degree of human intervention. Constantly monitoring new events, and curating training and validation sets, is tedious and time intensive. Significant human capital is required for such annotation endeavors. Also, involved efforts are required to tune the classifier for best performance. Developing and tuning classifiers manually using human intervention would not be a viable option if we are to monitor events and trends in real-time. We want to build a framework that would require very little human intervention to build and choose the best among the available performing classification techniques in our system. Another challenge with classification systems is related to their performance with unseen data. For the classification of tweets, we are continually faced with a situation where a given event contains a certain keyword that is closely related to it. If a classifier, built for a particular event, due to overfitting to what is a biased sample with limited generality, is faced with new tweets with different keywords, accuracy may be reduced. We propose building a system that will use very little training data in the initial iteration and will be augmented with automatically labelled training data from a collection that stores all the incoming tweets. A system that is trained on incoming tweets that are labelled using sophisticated techniques based on rich word vector representation would perform better than a system that is trained on only the initial set of tweets. We also propose to use sophisticated deep learning techniques like Convolutional Neural Networks (CNN) that can capture the combination of the words using an n-gram feature representation. Such sophisticated feature representation could account for the instances when the words occur together. We divide our case studies into two phases: preliminary and final case studies. The preliminary case studies focus on selecting the best feature representation and classification methodology out of the AR and the Word2Vec based Logistic Regression classification techniques. The final case studies focus on developing the augmented semi-supervised training methodology and the framework to develop a large collection learning optimizer to generate a highly performant classifier. For our preliminary case studies, we are able to achieve an F1 score of 0.96 that is based on Word2Vec and Logistic Regression. The AR classifier achieved an F1 score of 0.90 on the same data. For our final case studies, we are able to show improvements of F1 score from 0.58 to 0.94 in certain cases based on our augmented training methodology. Overall, we see improvement in using the augmented training methodology on all datasets. / Master of Science

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