3 resultados para Semantic mapping
em Digital Commons at Florida International University
Resumo:
The purpose of this phenomenological study was to describe how Colombian adult English language learners (ELL) select and use language learning strategies (LLS). This study used Oxford’s (1990a) taxonomy for LLS as its theoretical framework. Semi-structured interviews and a focus group interview, were conducted, transcribed, and analyzed for 12 Colombian adult ELL. A communicative activity known as strip story (Gibson, 1975) was used to elicit participants’ use of LLS. This activity preceded the focus group session. Additionally, participants’ reflective journals were collected and analyzed. Data were analyzed using inductive, deductive, and comparative analyses. Four themes emerged from the inductive analysis of the data: (a) learning conditions, (b) problem-solving resources, (c) information processing, and (d) target language practice. Oxford’s classification of LLS was used as a guide in deductively analyzing data concerning the participants’ experiences. The deductive analysis revealed that participants do not use certain strategies included in Oxford’s taxonomy at the third level. For example, semantic mapping, or physical response or sensation was not reported by participants. The findings from the inductive and deductive analyses were then compared to look for patterns and answers to the research questions. The comparative analysis revealed that participants used additional LLS that are not included in Oxford’s taxonomy. Some examples of these strategies are: using sound transcription in native language and help from children. The study was conducted at the MDC InterAmerican campus in South Florida, one of the largest Hispanic-influenced communities in the U.S. Based on the findings from this study, the researcher proposed a framework to study LLS that includes both external (i.e., learning context, community) and internal (i.e., culture, prior education) factors that influence the selection and use of LLS. The findings from this study imply that given the importance of the both external and internal factors in learners’ use of LLS, these factors should be considered for inclusion in any study of language learner strategies use by adult learners. Implications for teaching and learning as well as recommendations for further research are provided.
Resumo:
The Semantic Binary Data Model (SBM) is a viable alternative to the now-dominant relational data model. SBM would be especially advantageous for applications dealing with complex interrelated networks of objects provided that a robust efficient implementation can be achieved. This dissertation presents an implementation design method for SBM, algorithms, and their analytical and empirical evaluation. Our method allows building a robust and flexible database engine with a wider applicability range and improved performance. ^ Extensions to SBM are introduced and an implementation of these extensions is proposed that allows the database engine to efficiently support applications with a predefined set of queries. A New Record data structure is proposed. Trade-offs of employing Fact, Record and Bitmap Data structures for storing information in a semantic database are analyzed. ^ A clustering ID distribution algorithm and an efficient algorithm for object ID encoding are proposed. Mapping to an XML data model is analyzed and a new XML-based XSDL language facilitating interoperability of the system is defined. Solutions to issues associated with making the database engine multi-platform are presented. An improvement to the atomic update algorithm suitable for certain scenarios of database recovery is proposed. ^ Specific guidelines are devised for implementing a robust and well-performing database engine based on the extended Semantic Data Model. ^
Resumo:
Over the past five years, XML has been embraced by both the research and industrial community due to its promising prospects as a new data representation and exchange format on the Internet. The widespread popularity of XML creates an increasing need to store XML data in persistent storage systems and to enable sophisticated XML queries over the data. The currently available approaches to addressing the XML storage and retrieval issue have the limitations of either being not mature enough (e.g. native approaches) or causing inflexibility, a lot of fragmentation and excessive join operations (e.g. non-native approaches such as the relational database approach). ^ In this dissertation, I studied the issue of storing and retrieving XML data using the Semantic Binary Object-Oriented Database System (Sem-ODB) to leverage the advanced Sem-ODB technology with the emerging XML data model. First, a meta-schema based approach was implemented to address the data model mismatch issue that is inherent in the non-native approaches. The meta-schema based approach captures the meta-data of both Document Type Definitions (DTDs) and Sem-ODB Semantic Schemas, thus enables a dynamic and flexible mapping scheme. Second, a formal framework was presented to ensure precise and concise mappings. In this framework, both schemas and the conversions between them are formally defined and described. Third, after major features of an XML query language, XQuery, were analyzed, a high-level XQuery to Semantic SQL (Sem-SQL) query translation scheme was described. This translation scheme takes advantage of the navigation-oriented query paradigm of the Sem-SQL, thus avoids the excessive join problem of relational approaches. Finally, the modeling capability of the Semantic Binary Object-Oriented Data Model (Sem-ODM) was explored from the perspective of conceptually modeling an XML Schema using a Semantic Schema. ^ It was revealed that the advanced features of the Sem-ODB, such as multi-valued attributes, surrogates, the navigation-oriented query paradigm, among others, are indeed beneficial in coping with the XML storage and retrieval issue using a non-XML approach. Furthermore, extensions to the Sem-ODB to make it work more effectively with XML data were also proposed. ^