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A System For Natural Language Unmarked Clausal Transformations In Text-To-Text Applications, Daniel Miller Jun 2009

A System For Natural Language Unmarked Clausal Transformations In Text-To-Text Applications, Daniel Miller

Master's Theses

A system is proposed which separates clauses from complex sentences into simpler stand-alone sentences. This is useful as an initial step on raw text, where the resulting processed text may be fed into text-to-text applications such as Automatic Summarization, Question Answering, and Machine Translation, where complex sentences are difficult to process. Grammatical natural language transformations provide a possible method to simplify complex sentences to enhance the results of text-to-text applications. Using shallow parsing, this system improves the performance of existing systems to identify and separate marked and unmarked embedded clauses in complex sentence structure resulting in syntactically simplified source for …


Extraction Of Causal-Association Networks From Unstructured Text Data, Brett N. Bojduj Jun 2009

Extraction Of Causal-Association Networks From Unstructured Text Data, Brett N. Bojduj

Master's Theses

Causality is an expression of the interactions between variables in a system. Humans often explicitly express causal relations through natural language, so extracting these relations can provide insight into how a system functions. This thesis presents a system that uses a grammar parser to extract causes and effects from unstructured text through a simple, pre-defined grammar pattern. By filtering out non-causal sentences before the extraction process begins, the presented methodology is able to achieve a precision of 85.91% and a recall of 73.99%. The polarity of the extracted relations is then classified using a Fisher classifier. The result is a …


Bottom-Up Ontology Creation With A Direct Instance Input Interface, Charles C.H. Wei Apr 2009

Bottom-Up Ontology Creation With A Direct Instance Input Interface, Charles C.H. Wei

Master's Theses

In general an ontology is created by following a top-down, or so called genus-species approach, where the species are differentiated from the genus and from each other by means of differentiae [8]. The superconcept is the genus, every subconcept is a species, and the differentiae correspond to roles. To complete it a user organizes data into a proper structure, accompanied with the instances in that domain in order to complete the construction of an ontology. It is a concept learning procedure in a school, for example. Students first learn the general knowledge and apply it to their exercise and homework …


Application Of Parent-Child Uav Tasking For Wildfire Detection And Response, Stephen T. Kubik Dec 2008

Application Of Parent-Child Uav Tasking For Wildfire Detection And Response, Stephen T. Kubik

Master's Theses

In recent years, unmanned aerial vehicles (UAVs) have become a dominant force in the aerospace industry. Recent technological developments have moved these aircraft from remote operation roles to more active response missions. Of particular interest is the possibility of applying UAVs toward solving complex problems in long-endurance missions. Under that belief, the feasibility of utilizing UAVs for wildfire detection and response was investigated in a partnership that included NASA’s Aeronautics Research Mission Directorate and Science Mission Directorate, and the United States Forest Service. Under NASA’s Intelligent Mission Management (IMM) project, research was conducted to develop a mission architecture that would …