Online cooperation learning environment : a thesis presented in partial fulfillment of the requirements for the degree of Master of Science in Computer Science at Massey University, Albany, New Zealand

This project aims to create an online cooperation learning environment for students who study the same paper. Firstly, the whole class will be divided into several tutorial peer groups. One tutorial group includes five to seven students. The students can discuss with each other in the same study group, which is assigned by the lecturer. This is achieved via an online cooperation learning environment application (OCLE), which consists of a web based J2EE application and a peer to peer (P2P) java application, cooperative learning tool (CLT). It can reduce web server traffic significantly during online tutorial discussion time

A two-step approach to model precipitation extremes in California based on max-stable and marginal point processes

In modeling spatial extremes, the dependence structure is classically inferred by assuming that block maxima derive from max-stable processes. Weather stations provide daily records rather than just block maxima. The point process approach for univariate extreme value analysis, which uses more historical data and is preferred by some practitioners, does not adapt easily to the spatial setting. We propose a two-step approach with a composite likelihood that utilizes site-wise daily records in addition to block maxima. The procedure separates the estimation of marginal parameters and dependence parameters into two steps. The first step estimates the marginal parameters with an independence likelihood from the point process approach using daily records. Given the marginal parameter estimates, the second step estimates the dependence parameters with a pairwise likelihood using block maxima. In a simulation study, the two-step approach was found to be more efficient than the pairwise likelihood approach using only block maxima. The method was applied to study the effect of El Ni\~{n}o-Southern Oscillation on extreme precipitation in California with maximum daily winter precipitation from 35 sites over 55 years. Using site-specific generalized extreme value models, the two-step approach led to more sites detected with the El Ni\~{n}o effect, narrower confidence intervals for return levels and tighter confidence regions for risk measures of jointly defined events.Comment: Published at http://dx.doi.org/10.1214/14-AOAS804 in the Annals of Applied Statistics (http://www.imstat.org/aoas/) by the Institute of Mathematical Statistics (http://www.imstat.org

Involvement and determinants of ancient towns as tourist destinations: a case study of Wuzhen, China

Ancient towns have become one of the favorite destinations for Chinese tourists. In recent years, many local governments in China have been actively developing such tourism projects. However, the economic efficiency of different projects varies significantly. Some ancient towns are crowded with tourists whereas the others are rarely visited. The present study focuses on the influencing factors in the involvement of tourists’ decision-making on ancient town destinations, in order to help local administrative authorities to develop the market in a more efficient manner. The research hypotheses and conceptual model are put forward on the basis of literature review. Then the author designs the survey questionnaire and distributes copies among tourists in Wuzhen Ancient Town, China (simple sampling). After that, statistical analysis, independent-sample T test, one-way analysis of variance, correlation analysis and regression analysis are carried out to test the research hypotheses. Research findings: First, different tourists differ in advertising information factor, tourist attraction factor, destination image factor, social factor, cost factor and experience factor. Second, regression analysis suggests that the factors affecting the destination decision-making of ancient town tourists include advertising information factor, tourist attraction factor, destination image factor and social factor. Third, advertising information factor has the strongest influence on tourists' decision-making involvement, with the influence coefficient being 0.288. According to the research conclusions, the Researcher puts forward some management suggestions for the local management authorities of ancient towns: First, invest in strong destination advertising and information release; second, develop new tourist attraction factor; third, highlight the social functions of tourism; fourth, correctly position the destination image; fifth, focus on differentiating the marketing strategies of different source areas; sixth, divide the tourist market into segments and develop the tourism market in a targeted way.As cidades antigas tornaram-se um dos destinos favoritos dos turistas chineses. Nos últimos anos, muitos governos locais na China têm desenvolvido ativamente esses projetos de turismo. No entanto, a eficiência econômica de diferentes projetos varia significativamente. Algumas cidades antigas estão cheias de turistas, enquanto outras são raramente visitadas. O presente estudo enfoca os fatores que influenciam o envolvimento na tomada de decisões dos turistas na escolha de alguma cidade antiga como destino a visitar, a fim de ajudar as autoridades administrativas locais a desenvolver o mercado de maneira mais eficiente. As hipóteses de pesquisa e o modelo conceitual são apresentados com base na revisão da literatura. Em seguida, o autor cria o questionário da pesquisa e distribui cópias entre os turistas na Cidade Antiga de Wuzhen, China (amostragem simples). Depois disso, análise estatística, teste T de amostra independente, análise de variância unidirecional, análise de correlação e análise de regressão são realizados para testar as hipóteses de pesquisa. Resultados da pesquisa: Primeiro, distintos turistas diferem no fator de informação publicitária, fator de atração turística, fator de imagem de destino, fator social, fator de custo e fator de experiência. Segundo, a análise de regressão sugere que os fatores que afetam a tomada de decisão sobre o destino dos turistas de cidades antigas incluem o fator de informação publicitária, o fator de atração turística, o fator de imagem de destino e o fator social. Terceiro, o fator de informação de publicidade tem a influência mais forte no envolvimento da tomada de decisões dos turistas, com um coeficiente de influência de 0,288. De acordo com as conclusões da pesquisa, o autor apresenta algumas sugestões de gerenciamento para as autoridades administrativas locais das cidades antigas: Primeiro, investir em fortes anúncios de destinos e divulgação de informações; segundo, desenvolver novas atrações turísticas; terceiro, destacar as funções sociais do turismo; quarto, posicionar corretamente a imagem de destino; quinto, focar na diferenciação das estratégias de marketing para diferentes lugares emissores de turismo; sexto, dividir o mercado turístico em segmentos e desenvolvê-lo de forma direcionada

Users’ Continuance Participation in the Online Peer-to-peer Healthcare Community: A Text Mining Approach

The online peer-to-peer healthcare communities are known as the platform where dispersed groups of patients and their families query information, seek and offer support, and connect with others. The success of such communities relies on users’ ongoing involvement to generate benefits for both individuals and the communities. This study attempts to understand users’ continuance participation in online peer-to-peer healthcare community by classifying users’ goals of participation based on the user-generated text contents. We proposed a rule-based classification framework to categorize users’ goals of posting contents into four categories: information seeking, experience sharing, information sharing, and social interaction. We formalize and test the relationship between users’ continuance participation and all four posting goals, and find that the first three goals have significant impact on users’ continuance participation. Our findings can help researchers and practitioners better understand users’ behavior in the online peer-to-peer healthcare community

Neural Generative Question Answering

This paper presents an end-to-end neural network model, named Neural Generative Question Answering (GENQA), that can generate answers to simple factoid questions, based on the facts in a knowledge-base. More specifically, the model is built on the encoder-decoder framework for sequence-to-sequence learning, while equipped with the ability to enquire the knowledge-base, and is trained on a corpus of question-answer pairs, with their associated triples in the knowledge-base. Empirical study shows the proposed model can effectively deal with the variations of questions and answers, and generate right and natural answers by referring to the facts in the knowledge-base. The experiment on question answering demonstrates that the proposed model can outperform an embedding-based QA model as well as a neural dialogue model trained on the same data.Comment: Accepted by IJCAI 201

Nodal-line semimetals from Weyl superlattices

The existence and topological classification of lower-dimensional Fermi surfaces is often tied to the crystal symmetries of the underlying lattice systems. Artificially engineered lattices, such as heterostructures and other superlattices, provide promising avenues to realize desired crystal symmetries that protect lower-dimensional Fermi surface, such as nodal lines. In this work, we investigate a Weyl semimetal subjected to spatially periodic onsite potential, giving rise to several phases, including a nodal-line semimetal phase. In contrast to proposals that purely focus on lattice symmetries, the emergence of the nodal line in this setup does not require small spin-orbit coupling, but rather relies on its presence. We show that the stability of the nodal line is understood from reflection symmetry and a combination of a fractional lattice translation and charge-conjugation symmetry. Depending on the choice of parameters, this model exhibits drumhead surface states that are exponentially localized at the surface, or weakly localized surface states that decay into the bulk at all energies.Comment: 11 pages, 8 figures, Editors' Suggestio