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  • Thesis

  • Authors: Lu, Zhixiang (2006)

  • Ultrathin (10 nm 1 µm) poly(ethyl 2-cyanoacrylate) (PECA) films were prepared on flat surfaces via vapor deposition without experiencing the liquid phase. System pressure, monomer temperature, as well as surface initiators were studied in the process of controlling the thickness and roughness of polymer films. The growth of poly(ethyl 2-cyanoacrylate) film from patterned initiating surfaces resulted in patterned polymer films. Bulk and surface modifications have been studied in this dissertation to expand the application of poly(ethyl 2-cyanoacrylate) thin films. Polymer/metal composites were prepared using supercritical carbon dioxide. It was found that platinum formed homogeneous particles in poly(ethyl 2-cyanoacrylate) films, when poly(ethyl 2-cyanoacrylate)/poly(para-xylylene...

  • Thesis

  • Authors: Farber, Leslie (2006)

  • Lowe syndrome is an X-linked recessive disorder characterized by congenital cataracts, mental retardation, and abnormal kidney functions. Loss of function mutations in the OCRL1 gene lead to Lowe syndrome in all patients to date. The ocrll protein was previously identified as a PIP2 5-phosphatase localized to the trans-Golgi network. However, the mechanism through which loss of ocrll leads to the Lowe syndrome phenotype is still unknown. The aim of these studies was to define the cellular role of the PIP2 5-phosphatase, OCRL1, and its paralog, INPP5B. The first goal of this project was to study the ocrll paralog, INPP5B, in order to understand why Inpp5b can compensate for ocrll-deficiency in mice while the human ortholog cannot. In these studies, human INPP5B was found to express ...

  • Thesis

  • Authors: Keuper, Christine M. (2006)

  • Language communication is the successful interpretation of the speaker’s communicative intent. When Shakespeare writes, we see the intent in Romeo’s words, but it is lost again when we attempt to express it using a computer model for language; a model with an ability to handle tropes (metaphor, metonymy, synecdoche and irony) is needed. The goal of this model is to correctly interpret the nouns that occur within these tropes. Early computer language models had not worked well when they encountered tropes, yet the brain handled them easily. These early models concentrated on the language functions of the left temporal lobes of the brain; perhaps the models worked poorly because they had limited themselves to modelling only the parts of the brain that handled propositional language...

  • Thesis

  • Authors: Marton, Andras (2006)

  • The work presented in this thesis is aimed at optimizing the performance of the dye-sensitized solar cell (DSSC). Chapter 1 presents a brief overview of the history of solar cells and introduces the reader to the components, mechanisms and characterization techniques relevant to the DSSC. Chapter 2 describes the effect pH has on electron injection and collection processes in DSSC's. Charge collection efficiency, and not the electron injection yield, was related to the TiO2 surface protonation-deprotonation equilibria. In Chapter 3 we examine alternate redox mediators to optimize the regeneration of the oxidized sensitizer while maximizing open circuit voltage (Voc). Bipyrazine based ruthenium sensitizers anchored to SnO2 had higher photocurrent efficiencies and cell voltages with th...

  • Thesis

  • Authors: Nenkova, Ani (2006)

  • Recent years have seen unprecedented interest in news aggregation and browsing, with dedicated corporate and research websites becoming increasingly popular. Generic multi-document summarization can enhance users' experiences with such sites, and thus the development and evaluation of automatic summarization systems has become not only research, but a very practical challange. In this thesis, we describe a general modular automatic summarizer that achieves state of the art performance, present our experiments with rewrite of generic noun phrases and of references to people, and demonstrate how distinctions such as familiarity and salience of entities mentioned in the input can be automatically determined. We also propose an intrinsic evaluation method for summarization that incorpor...

  • Thesis

  • Authors: Sakellaridis, Loannis (2006)

  • The description of irreducible representations of a group G can be seen as a question in harmonic analysis; namely, decomposing a suitable space of functions on G into irreducibles for the action of G x G by left and right multiplication. For a split p-adic reductive group G over a local non-archimedean field, unramified irreducible smooth representations are in bijection with semisimple conjugacy classes in the "Langlands dual" group. In the first part of this work, we generalize this description to an arbitrary spherical variety X of G as follows: Irreducible quotients of the "unramified" Bernstein component of C°°(X) (or, more generally, CC°(X, LT), where L,y is a G-linear line bundle over X) are in natural almost bijection with (a number of copies of) the quotient of a complex...

  • Thesis

  • Authors: Olney, Andrew McGregor (2006)

  • This dissertation investigated the utility of latent semantic information for unsupervised grammar induction. Utility was directly measured by the relative performance of induced latent semantic grammars in parsing sentences and by the relative performance of induced grammars on making meaning judgments. Latent semantic grammars did not outperform the state of the art method for unsupervised parsing. However, latent semantic grammars performed as well or better than all other methods, indicating that latent semantic parsing is worthy of future research. Latent semantic grammars had equivalent performance to Latent Semantic Analysis on comparative meaning tasks, suggesting that latent semantic grammars are a patentable alternative to Latent Semantic Analysis. Finally, the non-orthogo...

  • Thesis

  • Authors: Ding, Pinghai (2006)

  • CHAPTER 3: The accuracy of nondestructive optical methods for chlorophyll (Chl) assessment based on leaf spectral characteristics depends on the wavelengths used for Chl assessment. To determine the optimum wavelengths for Chl assessment (OWchl) using reflectance spectroscopy, almond (Prunus dulcis (Mill.) D.A. Webb `Nonpareil'), poplar (UCC-1, a hybrid of Populus trichocarpa x P. deltoides, Union Camp, Princeton, NJ) and apple (Malus domestica Borkh `Fuji') trees were grown at different rates of nitrogen (N) fertilization to produce leaves with different Chl concentrations. Spectral reflectance of leaf discs was measured using a spectroradiometer (300 nm to 1100 nm at 1 nm intervals), and total CM concentration in leaf discs was determined. The OWchl for nondestructive Chl assessme...

  • Thesis

  • Authors: Lazarevich, Aleksandar (2006)

  • The field of computer forensics is continuously evolving and is still in its infancy when compared to other fields in the world of information technology. If one were to compare computer forensics to fields such as data mining, the immaturity of forensics becomes even more apparent and one can see that much more research is needed. Indus-try has developed many automated tools to perform data mining techniques but each implements a proven concept that has been validated. Even though these data mining concepts may have not been applied to ontologies, the precepts that the software is based on are defined in basic database theory and schemas. Software tools for computer forensics have been developed to automate the manual evidence discovery and capture procedures currently used by inve...

  • Thesis

  • Authors: Sun, Shuang (2006)

  • September 11 and hurricane Katrina have shown that timely information is important not only for disaster prevention but especially valuable in effective disaster response. From the point of view of information and communication technologies, the challenge is how to coordinate information sharing effectively among members of a complex decision-making team (e.g. the first responders for a disaster). A common difficulty is to provide useful and time-sensitive information to team members quickly but at the same time not overwhelm them with irrelevant information. This problem has also been encountered in other application domains that require effective communication in a team environment: examples include military command and control, heath care, and global enterprise. Research in the ...