1,804 research outputs found
APREGOAR: Development of a geospatial database applied to local news in Lisbon
Project Work presented as the partial requirement for obtaining a Master's degree in Geographic Information Systems and ScienceHá informações valiosas em formato de texto não estruturado sobre a localização, calendarização
e a essências dos eventos disponíveis no conteúdo de notícias digitais. Vários
trabalhos em curso já tentam extrair detalhes de eventos de fontes de notícias digitais,
mas muitas vezes não com a nuance necssária para representar com precisão onde as
coisas realmente acontecem. Alternativamente, os jornalistas poderiam associar manualmente
atributos a eventos descritos nos seus artigos enquanto publicam, melhorando a
exatidão e a confiança nestes atributos espaciais e temporais. Estes atributos poderiam
então estar imediatamente disponíveis para avaliar a cobertura temática, temporal e
espacial do conteúdo de uma agência, bem como melhorar a experiência do utilizador
na exploração do conteúdo, fornecendo dimensões adicionais que podem ser filtradas.
Embora a tecnologia de atribuição de dimensões geoespaciais e temporais para o
emprego de aplicaçãoes voltadas para o consumidor não seja novidade, tem ainda de
ser aplicada à escala das notícias. Além disso, a maioria dos sistemas existentes suporta
apenas uma definição pontual da localização dos artigos, que pode não representar bem
o(s) local(is) real(ais) dos eventos descritos.
Este trabalho define uma aplicação web de código aberto e uma base de dados
espacial subjacente que suporta i) a associação de múltiplos polígonos a representar
o local onde cada evento ocorre, os prazos associados aos eventos, em linha com os
atributos temáticos tradicionais associados aos artigos de notícias; ii) a contextualização
de cada artigo através da adição de mapas de eventos em linha para esclarecer aos
leitores onde os eventos do artigo ocorrem; e iii) a exploração dos corpora adicionados
através de filtros temáticos, espaciais e temporais que exibem os resultados em mapas
de cobertura interactivos e listas de artigos e eventos.
O projeto foi aplicado na área da grande Lisboa de Portugal. Para além da funcionalidade
acima referida, este projeto constroi gazetteers progressivos que podem ser
reutilizados como associações de lugares, ou para uma meta-análise mais aprofundada
do lugar, tal como é percebido coloquialmente. Demonstra a facilidade com que estas
dimensões adicionais podem ser incorporadas com grade confiança na precisão da definição, geridas, e alavancadas para melhorar a gestão de conteúdo das agências noticiosas,
a compreensão dos leitores, a exploração dos investigadores, ou extraídas para
combinação com outros conjuntos dos dados para fornecer conhecimentos adicionais.There is valuable information in unstructured text format about the location, timing,
and nature of events available in digital news content. Several ongoing efforts already
attempt to extract event details from digital news sources, but often not with the
nuance needed to accurately represent the where things actually happen. Alternatively,
journalists could manually associate attributes to events described in their articles while
publishing, improving accuracy and confidence in these spatial and temporal attributes.
These attributes could then be immediately available for evaluating thematic, temporal,
and spatial coverage of an agency’s content, as well as improve the user experience of
content exploration by providing additional dimensions that can be filtered.
Though the technology of assigning geospatial and temporal dimensions for the
employ of consumer-facing applications is not novel, it has yet to be applied at scale to
the news. Additionally, most existing systems only support a single point definition of
article locations, which may not well represent the actual place(s) of events described
within.
This work defines an open source web application and underlying spatial database
that supports i) the association of multiple polygons representing where each event
occurs, time frames associated with the events, inline with the traditional thematic
attributes associated with news articles; ii) the contextualization of each article via the
addition of inline event maps to clarify to readers where the events of the article occur;
and iii) the exploration of the added corpora via thematic, spatial, and temporal filters
that display results in interactive coverage maps and lists of articles and events.
The project was applied to the greater Lisbon area of Portugal. In addition to the
above functionality, this project builds progressive gazetteers that can be reused as place
associations, or for further meta analysis of place as it is colloquially understood. It
demonstrates the ease of which these additional dimensions may be incorporated with a
high confidence in definition accuracy, managed, and leveraged to improve news agency
content management, reader understanding, researcher exploration, or extracted for
combination with other datasets to provide additional insights
Uma ferramenta unificada para projeto, desenvolvimento, execução e recomendação de experimentos de aprendizado de máquina
Orientadores: Ricardo da Silva Torres, Anderson de Rezende RochaDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de ComputaçãoResumo: Devido ao grande crescimento do uso de tecnologias para a aquisição de dados, temos que lidar com grandes e complexos conjuntos de dados a fim de extrair conhecimento que possa auxiliar o processo de tomada de decisão em diversos domínios de aplicação. Uma solução típica para abordar esta questão se baseia na utilização de métodos de aprendizado de máquina, que são métodos computacionais que extraem conhecimento útil a partir de experiências para melhorar o desempenho de aplicações-alvo. Existem diversas bibliotecas e arcabouços na literatura que oferecem apoio à execução de experimentos de aprendizado de máquina, no entanto, alguns não são flexíveis o suficiente para poderem ser estendidos com novos métodos, além de não oferecerem mecanismos que permitam o reuso de soluções de sucesso concebidos em experimentos anteriores na ferramenta. Neste trabalho, propomos um arcabouço para automatizar experimentos de aprendizado de máquina, oferecendo um ambiente padronizado baseado em workflow, tornando mais fácil a tarefa de avaliar diferentes descritores de características, classificadores e abordagens de fusão em uma ampla gama de tarefas. Também propomos o uso de medidas de similaridade e métodos de learning-to-rank em um cenário de recomendação, para que usuários possam ter acesso a soluções alternativas envolvendo experimentos de aprendizado de máquina. Nós realizamos experimentos com quatro medidas de similaridade (Jaccard, Sorensen, Jaro-Winkler e baseada em TF-IDF) e um método de learning-to-rank (LRAR) na tarefa de recomendar workflows modelados como uma sequência de atividades. Os resultados dos experimentos mostram que a medida Jaro-Winkler obteve o melhor desempenho, com resultados comparáveis aos observados para o método LRAR. Em ambos os casos, as recomendações realizadas são promissoras, e podem ajudar usuários reais em diferentes tarefas de aprendizado de máquinaAbstract: Due to the large growth of the use of technologies for data acquisition, we have to handle large and complex data sets in order to extract knowledge that can support the decision-making process in several domains. A typical solution for addressing this issue relies on the use of machine learning methods, which are computational methods that extract useful knowledge from experience to improve performance of target applications. There are several libraries and frameworks in the literature that support the execution of machine learning experiments. However, some of them are not flexible enough for being extended with novel methods and they do not support reusing of successful solutions devised in previous experiments made in the framework. In this work, we propose a framework for automating machine learning experiments that provides a workflow-based standardized environment and makes it easy to evaluate different feature descriptors, classifiers, and fusion approaches in a wide range of tasks. We also propose the use of similarity measures and learning-to-rank methods in a recommendation scenario, in which users may have access to alternative machine learning experiments. We performed experiments with four similarity measures (Jaccard, Sorensen, Jaro-Winkler, and a TF-IDF-based measure) and one learning-to-rank method (LRAR) in the task of recommending workflows modeled as a sequence of activities. Experimental results show that Jaro-Winkler yields the highest effectiveness performance with comparable results to those observed for LRAR. In both cases, the recommendations performed are very promising and might help real-world users in different daily machine learning tasksMestradoCiência da ComputaçãoMestre em Ciência da Computaçã
Recommender systems in industrial contexts
This thesis consists of four parts: - An analysis of the core functions and
the prerequisites for recommender systems in an industrial context: we identify
four core functions for recommendation systems: Help do Decide, Help to
Compare, Help to Explore, Help to Discover. The implementation of these
functions has implications for the choices at the heart of algorithmic
recommender systems. - A state of the art, which deals with the main techniques
used in automated recommendation system: the two most commonly used algorithmic
methods, the K-Nearest-Neighbor methods (KNN) and the fast factorization
methods are detailed. The state of the art presents also purely content-based
methods, hybridization techniques, and the classical performance metrics used
to evaluate the recommender systems. This state of the art then gives an
overview of several systems, both from academia and industry (Amazon, Google
...). - An analysis of the performances and implications of a recommendation
system developed during this thesis: this system, Reperio, is a hybrid
recommender engine using KNN methods. We study the performance of the KNN
methods, including the impact of similarity functions used. Then we study the
performance of the KNN method in critical uses cases in cold start situation. -
A methodology for analyzing the performance of recommender systems in
industrial context: this methodology assesses the added value of algorithmic
strategies and recommendation systems according to its core functions.Comment: version 3.30, May 201
Recommended from our members
Investigating and Supporting Sensemaking within Online Health Communities
This dissertation focuses on understanding and supporting individual and collective sensemaking within online health communities (OHCs). This major goal was achieved in three aims. In Aim 1, this dissertation contributes a rich descriptive account of collective sensemaking in OHCs forums by describing how it occurs and develops, what triggers it, what elements constitute collective construction of meaning, and what conversational moves positively contribute to this process. Further, it describes how collective sensemaking in OHCs is impacted by the interplay between informational and socio-emotional needs of OHCs members. Moreover, it examines how design of different social computing platforms influences OHCs members’ ability to meet their informational and socio-emotional needs and engage in collective sensemaking. In Aim 2, this dissertation explores the design space of tools for supporting individual sensemaking through optimized information access. Through the design and evaluation of a prototype DisVis it examines the impact of such tools on OHCs members’ ability to understand information within discussion threads. In the final Aim 3, this dissertation proposes a novel approach for meeting the three main needs identified in Aims 1 and 2: promoting individual sensemaking, while at the same time encouraging collective sensemaking, and facilitating development of social awareness and ties among community members. The design and evaluation of the novel solution for visualizing discussion threads that synergistically addresses these three needs—dSense—provides insights for future research and design of interactive solutions for supporting individual and collective sensemaking within OHCs
Power to the Teachers:An Exploratory Review on Artificial Intelligence in Education
This exploratory review attempted to gather evidence from the literature by shedding light on the emerging phenomenon of conceptualising the impact of artificial intelligence in education. The review utilised the PRISMA framework to review the analysis and synthesis process encompassing the search, screening, coding, and data analysis strategy of 141 items included in the corpus. Key findings extracted from the review incorporate a taxonomy of artificial intelligence applications with associated teaching and learning practice and a framework for helping teachers to develop and self-reflect on the skills and capabilities envisioned for employing artificial intelligence in education. Implications for ethical use and a set of propositions for enacting teaching and learning using artificial intelligence are demarcated. The findings of this review contribute to developing a better understanding of how artificial intelligence may enhance teachers’ roles as catalysts in designing, visualising, and orchestrating AI-enabled teaching and learning, and this will, in turn, help to proliferate AI-systems that render computational representations based on meaningful data-driven inferences of the pedagogy, domain, and learner models
Recommended from our members
User Interfaces for Patient-Centered Communication of Health Status and Care Progress
The recent trend toward patients participating in their own healthcare has opened up numerous opportunities for computing research. This dissertation focuses on how technology can foster this participation, through user interfaces to effectively communicate personal health status and care progress to hospital patients. I first characterize the design space for electronic information communication to patients through field studies conducted in multiple hospital settings. These studies utilize a combination of survey instruments, and low- and high-fidelity prototypes, including a document-editing prototype through which users can view and manage clinical data to automatically associate it with progress notes. The prototype, activeNotes, includes the first known techniques supporting clinical information requests directly within a document editor. A usage study with ICU physicians at New York-Presbyterian Hospital (NYP) substantiated our design and revealed how electronic information related to patient status and care progress is derived from a typical Electronic Health Record system. Insights gained from this study informed following studies to understand how to design abstracted, plain-language views suitable for patients. We gauged both patient and physician responses to information display prototypes deployed in patient rooms for a formative study exploring their design. Following my reports on this study, I discuss the design, development and pilot evaluations of a prototype Personal Health Record application providing live, abstracted clinical information for patients at NYP. The portal, evaluated by cardiothoracic surgery patients, is the first of its kind to allow patients to capture and monitor live data related to their care. Patient use of the portal influenced the subsequent design of tools to support users in making sense of online medication information. These tools, designed with nurses and pharmacists and evaluated by cardiothoracic surgery patients at NYP, were developed using topic modeling approaches and text analysis techniques. Embodied in a prototype called Remedy, they enable rapid filtering and comparison of medication-related search results, based on a number of website features and content topics. I conclude by discussing how findings from this series of studies can help shape the ongoing design and development of patient-centered technology
Organization and Usage of Learning Objects within Personal Computers
Research report of the ProLearn Network of Excellence (IST 507310), Deliverable 7.6To promote the integration of Desktop related Knowledge Management and Technology Enhanced Learning this deliverable aims at increasing the awareness of Desktop research within the Professional Learning community and at familiarizing the e-Learning researchers with the state-of-the-art in the relevant areas of Personal Information Management (PIM), as well as with the currently on-going activities and some of the regular PIM publication venues
CoMMA Corporate Memory Management through Agents Corporate Memory Management through Agents: The CoMMA project final report
This document is the final report of the CoMMA project. It gives an overview of the different search activities that have been achieved through the project. First, a description of the general requirements is proposed through the definition of two scenarios. Then it shows the different technical aspects of the projects and the solution that has been proposed and implemented
- …