Self-cleaning Polyurethane and Polyester Coatings

Self-cleaning titanium dioxide (TiO2) based polyurethane and polyester nanocomposites were synthesized, characterized and tested in this thesis. A monomer functionalization method (“grafting from” polymerization) was used for synthesizing both novel nano-TiO2 coordinated polyurethanes (nano-TiO2-PU) and nano-TiO2/polyester nanocomposites. This technique provides the advantage of directly attaching nanoparticles to the polymer backbone. For polyurethane synthesis, two different methods (one-shot and pre-polymer) were explored. Using several characterization techniques, product from the pre-polymer method showed better mechanical properties; therefore, the pre-polymer method was chosen for subsequent nano-TiO2-PU synthesis. In the nano-TiO2-PU synthesis, the first step, monomer functionalization, was confirmed using TGA and FTIR characterization. The self-cleaning properties of nano-TiO2-PU products were examined and demonstrated. As for polyesters, nano-TiO2 was mixed with two commercial polyesters to investigate their self-cleaning and mechanical properties. With the addition of nano-TiO2, nano-TiO2/polycaprolactone (PCL) showed good self-cleaning properties and nano-TiO2/poly(ethylene terephthalate) (PET) showed enhancement in the mechanical properties

Working in the US for Recent Highly Educated Asian Immigrants and How Social Class Shift Impacted Their Experiences

This dissertation utilized the Consensual Qualitative Research (CQR) method to understand the work experiences of recently arrived, highly educated Asian immigrants, specifically from Chinese and Taiwanese backgrounds, in the United States. Grounded in the Psychology of Working Theory, the study places a particular emphasis on the role of social class in shaping how immigrants conceptualize decent work and meaningful work as well as how they adapt in order to achieve their desired work experience after immigration. Through CQR analysis, nine distinct domains emerged, shedding light on the multifaceted nature of their professional journeys and the challenges and opportunities Asian immigrants encountered. Each domain is comprehensively explored, offering a deepened understanding of the unique interplay between cultural, educational, and professional dynamics for this specific population. Additionally, this study offers implications for both future research and practice, emphasizing the need for culturally attuned frameworks in understanding the diverse challenges and strengths of this population

MatchZoo: A Learning, Practicing, and Developing System for Neural Text Matching

Text matching is the core problem in many natural language processing (NLP) tasks, such as information retrieval, question answering, and conversation. Recently, deep leaning technology has been widely adopted for text matching, making neural text matching a new and active research domain. With a large number of neural matching models emerging rapidly, it becomes more and more difficult for researchers, especially those newcomers, to learn and understand these new models. Moreover, it is usually difficult to try these models due to the tedious data pre-processing, complicated parameter configuration, and massive optimization tricks, not to mention the unavailability of public codes sometimes. Finally, for researchers who want to develop new models, it is also not an easy task to implement a neural text matching model from scratch, and to compare with a bunch of existing models. In this paper, therefore, we present a novel system, namely MatchZoo, to facilitate the learning, practicing and designing of neural text matching models. The system consists of a powerful matching library and a user-friendly and interactive studio, which can help researchers: 1) to learn state-of-the-art neural text matching models systematically, 2) to train, test and apply these models with simple configurable steps; and 3) to develop their own models with rich APIs and assistance

Using the organizational and narrative thread structures in an e-book to support comprehension.

Stories, themes, concepts and references are organized structurally and purposefully in most books. A person reading a book needs to understand themes and concepts within the context. Schanks Dynamic Memory theory suggested that building on existing memory structures is essential to cognition and learning. Pirolli and Card emphasized the need to provide people with an independent and improved ability to access and understand information in their information seeking activities. Through a review of users reading behaviours and of existing e-Book user interfaces, we found that current e-Book browsers provide minimal support for comprehending the content of large and complex books. Readers of an e-Book need user interfaces that present and relate the organizational and narrative structures, and moreover, reveal the thematic structures. This thesis addresses the problem of providing readers with effective scaffolding of multiple structures of an e-Book in the user interface to support reading for comprehension. Recognising a story or topic as the basic unit in a book, we developed novel story segmentation techniques for discovering narrative segments, and adapted story linking techniques for linking narrative threads in semi-structured linear texts of an e-Book. We then designed an e-Book user interface to present the complex structures of the e-Book, as well as to assist the reader to discover these structures. We designed and developed evaluation methodologies to investigate reading and comprehension in e-Books, in order to assess the effectiveness of this user interface. We designed semi-directed reading tasks using a Story-Theme Map, and a set of corresponding measurements for the answers. We conducted user evaluations with book readers. Participants were asked to read stories, to browse and link related stories, and to identify major themes of stories in an e-Book. This thesis reports the experimental design and results in detail. The results confirmed that the e-Book interface helped readers perform reading tasks more effectively. The most important and interesting finding is that the interface proved to be more helpful to novice readers who had little background knowledge of the book. In addition, each component that supported the user interface was evaluated separately in a laboratory setting and, these results too are reported in the thesis