258 research outputs found
User contribution measurement model for web-based discussion forums
The success of social software depends on contributions made by two key entities; the infrastructure provider(s) and the content providers (users). Currently, social software providers do not possess a powerful and generic approach to measure the contributions of their users. The ability of measuring user contributions will allow social software providers to accurately identify, acknowledge and reward their content contributors. As a result, content providers may become motivated to contribute content more regularly. This paper proposes a user contribution measurement model which is validated against an operational web-based discussion forum
Web Spambot Detection Based on Web Navigation Behaviour
Web robots have been widely used for various beneficial and malicious activities. Web spambots are a type of web robot that spreads spam content throughout the web by typically targeting Web 2.0 applications. They are intelligently designed to replicate human behaviour in order to bypass system checks. Spam content not only wastes valuable resources but can also mislead users to unsolicited websites and award undeserved search engine rankings to spammers' campaign websites. While most of the research in anti-spam filtering focuses on the identification of spam content on the web, only a few have investigated the origin of spam content, hence identification and detection of web spambots still remains an open area of research.In this paper, we describe an automated supervised machine learning solution which utilises web navigation behaviour to detect web spambots. We propose a new feature set (referred to as an action set) as a representation of user behaviour to differentiate web spambots from human users. Our experimental results show that our solution achieves a 96.24% accuracy in classifying web spambots
Assessing Post Usage for Measuring the Quality of Forum Posts
It has become difficult to discover quality content within forums websites due to the increasing amount of UserGenerated Content (UGC) on the Web. Many existing websites have relied on their users to explicitly rate content quality. The main problem with this approach is that the majority of content often receives insufficient rating. Current automated content rating solutions have evaluated linguistic features of UGC but are less effective for different types of online communities. We propose a novel approach that assesses post usage to measure the quality of forum posts. Post usage can be viewed as implicit user ratings derived from their usage behaviour. The proposed model is validated against an operational forum using Matthews Correlation Coefficient to measure performance. Our model serves as a basis of exploring content usage to measure content quality in forums and other Web 2.0 platforms
Editorial-The 6th International Workshop on Modeling the Ocean (IWMO 2014)
The 6th International Workshop on Modeling the Ocean (IWMO 2014) was held on June 23–27, 2014, at Dalhousie University in Halifax, Nova Scotia, Canada. After three meetings in Asia (Oey et al. 2010, 2013a, b) and one in Europe (Berntsen et al. 2014), the IWMO returned to North America for the second time (since IWMO 2010 in the USA; Ezer et al. 2011). Readers are referred to https://www.dal.ca/sites/iwmo. html for more information on IWMO 2014 and http://www. ccpo.odu.edu/POMWEB /meetings.htm for information on the past meetings and future planned meetings
Optometric extension program: 1991 bibliography of near lenses and vision training research
Optometric extension program: 1991 bibliography of near lenses and vision training researc
Solar Chromospheric Temperature Diagnostics: a joint ALMA-H analysis
We present the first high-resolution, simultaneous observations of the solar
chromosphere in the optical and millimeter wavelength ranges, obtained with
ALMA and the IBIS instrument at the Dunn Solar Telescope. In this paper we
concentrate on the comparison between the brightness temperature observed in
ALMA Band 3 (3 mm; 100 GHz) and the core width of the H 656.3 nm line,
previously identified as a possible diagnostic of the chromospheric
temperature. We find that in the area of plage, network and fibrils covered by
our FOV the two diagnostics are well correlated, with similar spatial
structures observed in both. The strength of the correlation is remarkable,
given that the source function of the mm-radiation obeys local thermodynamic
equilibrium, while the H line has a source function that deviates
significantly from the local Planck function. The observed range of ALMA
brightness temperatures is sensibly smaller than the temperature range that was
previously invoked to explain the observed width variations in H. We
employ analysis from forward modeling with the RH code to argue that the strong
correlation between H width and ALMA brightness temperature is caused
by their shared dependence on the population number of the first excited
level of hydrogen. This population number drives millimeter opacity through
hydrogen ionization via the Balmer continuum, and H width through a
curve-of-growth-like opacity effect. Ultimately, the population is
regulated by the enhancement or lack of downward Ly flux, which
coherently shifts the formation height of both diagnostics to regions with
different temperature, respectively.Comment: Accepted for publication in Ap
Estimation of outcrossing rates in Koompassia malaccensts from an open-pollinated population in Peninsular Malaysia using microsatellite markers
Koompassia malaccensis (Leguminosae), locally known as kempas, is an important tropical timber species in South-East Asia. Although studies have shown that most tropical tree species are predominantly outcrossing, there is no empirical support for this species prior to this study, with regard to its mating system. Information on its reproductive biology is also scanty. We report the estimation of the outcrossing rates of K. malaccensis using microsatellite markers, based on a fruiting season at the Semangkok Forest Reserve, Selangor. Microsatellite analysis was performed for an average of 46 seeds each from nine adult K. malaccensis trees, using four polymorphic microsatellite loci (Kma050, Kma067, Kma147 and Kma180). Single and multilocus population outcrossing estimates (ts and tm respectively) were determined using the software MLTR version 3.0. Results showed that this timber species was predominantly outcrossing (tm = 0.890). Biparental mating (tm – ts) was very low, only 0.026, suggesting low tendency of mating between relatives. Outcrossing estimates obtained for individual mother trees were in the range of 0.637 to 0.994. The relatively lower outcrossing rates exhibited by a few progeny arrays indicated that K. malaccensis was not completely self-incompatible
The Twittering Presidents An analysis of tweets from @BarackObama and @realDonaldTrump
This paper uses a Systemic Functional Multimodal Discourse Analysis (SF-MDA) approach to analyse tweets from the Twitter accounts of Presidents Barack Obama (@Barack Obama) and Donald Trump (@realDonaldTrump). The tweets were posted during the last nine months of President Obama’s effective presidency and the first nine months of President Trump’s presidency. The tweets are analysed using automated text analysis which is interpreted through an SF-MDA lens, supplemented by manual analysis. The analysis examines ideational and interpersonal emphasis in the tweets with the aim of showing how the composition and content construct a view of how each president and his presidency are presented to the public. The findings suggest marked contrasts in presidential style with President Trump foregrounding the interpersonal while President Obama foregrounds the ideational. Where President Trump presents as self-promoting, autocratic, opinionated and igniting discord in his tweets, President Obama presents as democratic, moderate, restrained and seeking social harmony
Towards a Discipline of Multimodality: Parallels to Mathematics and Linguistics and New Ways Forward
Multimodality, involving the study of meaning arising from the integration of language with images and other resources in multimodal texts, interactions and events, addresses the fundamental need to understand human communication in the current age of digital technology. However, multimodality is not considered to be a discipline per se at present. By drawing parallels between mathematics and linguistics, it is proposed that if multimodality is to become a discipline, then abstract context-based frameworks for modeling multimodal semiotic resources and methodologies for investigating patterns of human communication are required. An example of how this could be achieved is provided. From here, multimodality has the potential to provide the foundations for a range of multimodal sciences, in much the same way that mathematics and linguistics underpin the mathematical and language sciences respectively. In doing so, it may become possible to track the changes in human communication arising from digital technology and the resultant impact on thought and reality
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