757 research outputs found

    The Royal Birth of 2013: Analysing and Visualising Public Sentiment in the UK Using Twitter

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    Analysis of information retrieved from microblogging services such as Twitter can provide valuable insight into public sentiment in a geographic region. This insight can be enriched by visualising information in its geographic context. Two underlying approaches for sentiment analysis are dictionary-based and machine learning. The former is popular for public sentiment analysis, and the latter has found limited use for aggregating public sentiment from Twitter data. The research presented in this paper aims to extend the machine learning approach for aggregating public sentiment. To this end, a framework for analysing and visualising public sentiment from a Twitter corpus is developed. A dictionary-based approach and a machine learning approach are implemented within the framework and compared using one UK case study, namely the royal birth of 2013. The case study validates the feasibility of the framework for analysis and rapid visualisation. One observation is that there is good correlation between the results produced by the popular dictionary-based approach and the machine learning approach when large volumes of tweets are analysed. However, for rapid analysis to be possible faster methods need to be developed using big data techniques and parallel methods.Comment: http://www.blessonv.com/research/publicsentiment/ 9 pages. Submitted to IEEE BigData 2013: Workshop on Big Humanities, October 201

    Relational Benefits and Costs in Channel Distribution: A Dyadic Research From Buyers and Sellers Perspective

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    The benefits from having long–term relationships with customers have become a focal topic and have been widely discussed in the marketing literature (Dwyer, Schurr and Oh 1987; Reichheld and Sasser 1990; Reichheld 1993; Morgan and Hunt 1994; Walter, Ritter and Gemuden 2001). However, careful review of the literature indicates that the literature is deficient in several ways: (1) relational benefits are mostly examined in term of economic benefits, especially in b2b and channel distribution contexts, (2) there is limited number of studies examining cost dimensions, (3) there is lack of studies examines both benefits and costs from dyadic perspective (i.e. data collected from both sides of the relationship—buyers and sellers), and (4) little is known about the interactions between relationship benefits/costs with other important relational construct, e.g. relationship commitment. In light with these problems, we need a systematic framework (Walter, Ritter, and Gemunden 2001), which should not only examine relational benefits and cost from a dyadic perspective, but also investigate the interactions between relational benefits and costs with other important relational constructs such as relationship commitment. Building and testing this kind of framework, thus, is the major purpose of this research. Four studies, two qualitative and two quantitative, were conducted in Hochiminh City, Vietnam, to test the proposed framework. The result shows that there are four groups of benefits that buyers and sellers expect to have from long-term relationships: economic benefits, social benefits, confidence benefits and informational benefits. Relationships, however, are not without costs. Maintenance costs including time, efforts, and resources are major type of costs that buyers and sellers are facing in long-term relationships. Both relational benefits and costs strongly impacted the commitment in the relationship, but in opposite directions. While relational benefits positively impacted commitment, relational costs negatively impacted commitment. Study limitations, managerial implications, and recommendations for future research are also presented

    Décomposition photocatalytique du méthanol sur des nanosphères de TiO₂ chargées de métal

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    353121\uThe utilization of solar light-driven photocatalysts has attracted an increasing attention in creating green energy and purifying environment from harmful pollutants. In photocatalysis technology, semiconductor-based photocatalysis has diverse applications including the decomposition of organic pollutants. In particular, titanium dioxide (TiO₂)-based photocatalysts have been extensively studied because of their low cost and outstanding physical and chemical properties. However, the photocatalytic performance of TiO₂ is not very high due to the weak light absorption and the fast charge carrier recombination. Therefore, the main target of the research presented in this thesis is to develop new methods to prepare more efficient materials based on TiO₂ for organic pollutants decomposition. For this purpose, the uniform titanate nanodisks (TNDs) with an average diameter of 22 nm were first synthesized by using different types of capping agents, including benzyl alcohol (BA), benzyl ether (BE) and oleylamine (OM). SiO₂ nanospheres (SiO₂ NSs) in nanoscale diameter as the core of the structure were then coated with TNDs using a layer-by-layer deposition technique in the presence of polyethylenimine (PEI) solution to design the TND-PEI/SiO₂ NSs. Based on the developed TND-PEI/SiO₂ NSs, creating a heterojunction between TiO₂ and other visible light active semiconductors is one of the interesting ways to optimize and enhance performance of TiO₂ in the visible region. In order to synthesize these TiO₂-based heterojunction composites, several cation (Cu²⁺, Ni²⁺, and Pt²⁺) solutions were loaded over TND-PEI/SiO₂ NSs to obtain CuO/TiO₂/SiO₂, Ni²⁺/TiO₂/SiO₂ or Pt²⁺/TiO₂/SiO₂ materials, respectively. The co-existence of CuO, Ni²⁺, and Pt²⁺ functioning as co-catalysts led to a remarkable enhancement of the photocatalytic performance of TiO₂. The new developed materials have shown not only high porosity and high specific surface area, but also strong solar light absorption. As a result, the photocatalytic activity of these new materials and the effect of different co-catalysts were investigated in the photocatalytic decomposition of methanol. TiO₂-based heterojunction composites (CuO/TiO₂/SiO₂) was further treated by H₂S. This non-metal doping TiO₂ is a well-known and effective way to decrease the band gap, which can result in the absorption of more visible light. The photodegradation of methanol in aqueous solution was deployed to test the photocatalytic activities of TiO₂-based material and further widens its applications in water treatment. These modifications proved that the light absorption of CuO/TiO₂ was improved compared with Ni²⁺/TiO₂ and Pt²⁺/TiO₂. CuO/TiO₂ material after H₂S treatment was found to exhibit a good performance in the degradation of methanol from aqueous solutions under solar light irradiation

    Cultural-Artistic Value in Epic and Festival of the Muong Thanh Hoa People

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    The epic The Land of the Earth is a system of mythical stories about the formation of heaven and earth of the Muong. It is also considered history and an encyclopedia of the customs of the Muong people. This epic is both pride and respect in the cultural life of the Muong community. This article studies several outstanding cultural symbols of the epic "Land for the Land" which have been preserved and remained quite intact in the Poon Poong festival - one of the most important festivals of the Muong people in Thanh Hoa

    Proximity for Sums of Composite Functions

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    We propose an algorithm for computing the proximity operator of a sum of composite convex functions in Hilbert spaces and investigate its asymptotic behavior. Applications to best approximation and image recovery are described
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