9 resultados para unclean internet data
em QUB Research Portal - Research Directory and Institutional Repository for Queen's University Belfast
Resumo:
Query processing over the Internet involving autonomous data sources is a major task in data integration. It requires the estimated costs of possible queries in order to select the best one that has the minimum cost. In this context, the cost of a query is affected by three factors: network congestion, server contention state, and complexity of the query. In this paper, we study the effects of both the network congestion and server contention state on the cost of a query. We refer to these two factors together as system contention states. We present a new approach to determining the system contention states by clustering the costs of a sample query. For each system contention state, we construct two cost formulas for unary and join queries respectively using the multiple regression process. When a new query is submitted, its system contention state is estimated first using either the time slides method or the statistical method. The cost of the query is then calculated using the corresponding cost formulas. The estimated cost of the query is further adjusted to improve its accuracy. Our experiments show that our methods can produce quite accurate cost estimates of the submitted queries to remote data sources over the Internet.
Resumo:
Over the years, researchers from different disciplines have used a wide variety of research methods to assess the views of children. Qualitative methods such as focus groups and small group discussions are particularly common. Much rarer are large-scale quantitative surveys that are a valuable way of comparing data from across different age groups and countries and over time. To test the feasibility of carrying out large-scale quantitative research with children, the authors undertook a pilot survey in Northern Ireland in June 2008. There were two notable innovations: First, it was a survey of all Primary 7 children (age 10 and 11 years); second, it used the Internet to gather the information, which has not been done on this scale before. This article discusses the methodology used to implement the pilot study and evaluates the use of the Internet for carrying out survey research with children.
Resumo:
The WASP (wide angle search for planets) project is an exoplanet transit survey that has been automatically taking wide field images since 2004. Two instruments, one in La Palma and the other in South Africa, continually monitor the night sky, building up light curves of millions of unique objects. These light curves are used to search for the characteristics of exoplanetary transits. This first public data release (DR1) of the WASP archive makes available all the light curve data and images from 2004 up to 2008 in both the Northern and Southern hemispheres. A web interface () to the data allows easy access over the Internet. The data set contains 3 631 972 raw images and 17 970 937 light curves. In total the light curves have 119 930 299 362 data points available between them.
Resumo:
ARK (‘Access Research Knowledge’) was set up with a single goal: to make social science information on Northern Ireland available to the widest possible audience. The most well-known and widely used part of the ARK resource is CAIN (Conflict Archive on the INternet), which is one of the largest on-line collections of source material and information and about the Northern Ireland conflict. The compilation of CAIN's new Remembering: Victims, Survivors and Commemoration section raised issues related to the sensitivity of the material, as it feeds into the fundamental debate on the legacy of the Northern Ireland conflict. It also fundamentally raises the question to what extent archiving is a neutral or political activity and necessitates a discourse on responsibility and ethics among social researchers. Experiences from the establishment of the Northern Ireland Qualitative Archive (NIQA) shed light on future possibilities with regard to qualitative archives on the Northern Ireland conflict.
Resumo:
This paper uses data from the 2009 Kids’ Life and Times Survey, involving 3657 children aged 10 or 11 years old in Northern Ireland. The survey indicated high levels of use of Internet applications, including social-networking sites and online games. Using the KIDSCREEN-27 instrument, the data indicate that the use of social-networking sites and online games is related to poorer psychological well-being among girls, but not boys. Boys and girls who experience “cyberbullying” have poorer psychological well-being. This association between psychological well-being and some Internet applications merits more attention in future research and policy development.
Resumo:
This paper uses data from the 2009 Kids’ Life and Times Survey, involving 3657 children aged 10 or 11 years old in Northern Ireland. The survey indicated high levels of use of Internet applications, including social-networking sites and online games. Using the KIDSCREEN-27 instrument, the data indicate that the use of social-networking sites and online games is related to poorer psychological well-being among girls, but not boys. Boys and girls who experience “cyberbullying” have poorer psychological well-being. This association between psychological well-being and some Internet applications merits more attention in future research and policy development.
Resumo:
The increasing adoption of cloud computing, social networking, mobile and big data technologies provide challenges and opportunities for both research and practice. Researchers face a deluge of data generated by social network platforms which is further exacerbated by the co-mingling of social network platforms and the emerging Internet of Everything. While the topicality of big data and social media increases, there is a lack of conceptual tools in the literature to help researchers approach, structure and codify knowledge from social media big data in diverse subject matter domains, many of whom are from nontechnical disciplines. Researchers do not have a general-purpose scaffold to make sense of the data and the complex web of relationships between entities, social networks, social platforms and other third party databases, systems and objects. This is further complicated when spatio-temporal data is introduced. Based on practical experience of working with social media datasets and existing literature, we propose a general research framework for social media research using big data. Such a framework assists researchers in placing their contributions in an overall context, focusing their research efforts and building the body of knowledge in a given discipline area using social media data in a consistent and coherent manner.
Resumo:
A first-stage collision database is assembled which contains electron-impact excitation, ionization, and recombination rate coefficients for Be, Be+, Be2+, and Be3+. The first-stage database is constructed using the R-matrix with pseudo-states, time-dependent close-coupling, and perturbative, distorted-wave methods. A second-stage collision database is then assembled which contains generalized collisional-radiative and radiated power loss coefficients. The second-stage database is constructed by solution of collisional-radiative equations in the quasi-static equilibrium approximation using the first-stage database. Both collision database stages reside in electronic form at the ORNL Controlled Fusion Atomic Data Center and in the ADAS database, and are easily accessed over the worldwide internet. © 2007 Elsevier Inc. All rights reserved.
Resumo:
A first stage collision database is assembled which contains electron-impact effective collision strengths, and ionization and recombination rate coefficients for Li, Li+, and Li2+. The first stage database is constructed using the R-matrix with pseudo-states, time-dependent close-coupling, converged close-coupling, and perturbative distorted-wave methods. A second stage collision database is then assembled which contains generalized collisional-radiative and radiated power loss coefficients. The second stage database is constructed by solution of collisional-radiative equations in the quasi-static equilibrium approximation using the first stage database. Both collision database stages reside in electronic form at the ORNL Controlled Fusion Atomic Data Center and in the ADAS database, and are easily accessed over the worldwide internet. ?? 2006 Elsevier Inc. All rights reserved.