793,843 research outputs found

    BeCAPTCHA-Type: Biometric Keystroke Data Generation for Improved Bot Detection

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    This work proposes a data driven learning model for the synthesis of keystroke biometric data. The proposed method is compared with two statistical approaches based on Universal and User-dependent models. These approaches are validated on the bot detection task, using the keystroke synthetic data to improve the training process of keystroke-based bot detection systems. Our experimental framework considers a dataset with 136 million keystroke events from 168 thousand subjects. We have analyzed the performance of the three synthesis approaches through qualitative and quantitative experiments. Different bot detectors are considered based on several supervised classifiers (Support Vector Machine, Random Forest, Gaussian Naive Bayes and a Long Short-Term Memory network) and a learning framework including human and synthetic samples. The experiments demonstrate the realism of the synthetic samples. The classification results suggest that in scenarios with large labeled data, these synthetic samples can be detected with high accuracy. However, in few-shot learning scenarios it represents an important challenge. Furthermore, these results show the great potential of the presented models.Comment: Paper accepted in IEEE Computer Society Workshop on Biometrics (CVPRw) 202

    Striking a Balance: Evidence Synthesis Support for Graduate Students

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    Evidence synthesis (ES) is the process of systematically collecting studies and synthesizing the findings using strict protocols and criteria. Common examples of ES include systematic reviews, meta-analyses, and scoping reviews. While ES has been commonplace in health sciences for many years, it has recently gained traction in non-health sciences fields such as the social sciences. In response to this growing trend, the IMLS-funded Evidence Synthesis Institute was created to offer librarians in-depth training on how to best provide ES support to disciplines outside the health sciences. This presentation draws on the insights of two liaison librarians who work at public R1 universities and who recently attended the Evidence Synthesis Institute. After completing the Institute and gaining a deeper understanding of ES, both librarians have grappled with the best way to implement an ES service in their organizations. The presenters will share two different approaches: one will discuss their word-of-mouth approach to those in their liaison areas, and the other will discuss their role in building a brand new ES program that serves many disciplines. By comparing and contrasting their programs, the presenters will share practical insights into the workflows, relationships, and considerations of providing ES support. Some topics that will be explored include the type of service model (ad hoc versus institutional), getting buy-in from library staff, training, time management, and promotion of the service. The discussion will focus on graduate students in particular and offer advice on how librarians can provide ES support to a contingency that is both researcher and student. The presenters will discuss how they have managed to strike a balance between guiding graduate students on their ES projects while leaving room for graduate students to learn the process themselves. This session will be of interest to librarians who are excited to learn about a new research area and interested in how to support their users, library staff who lack institutional infrastructure and find themselves at an impasse when trying to identify where they fit in this new functional area, and for administrators responsible for setting strategic directions

    Reuse at the Software Productivity Consortium

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    The Software Productivity Consortium is sponsored by 14 aerospace companies as a developer of software engineering methods and tools. Software reuse and prototyping are currently the major emphasis areas. The Methodology and Measurement Project in the Software Technology Exploration Division has developed some concepts for reuse which they intend to develop into a synthesis process. They have identified two approaches to software reuse: opportunistic and systematic. The assumptions underlying the systematic approach, phrased as hypotheses, are the following: the redevelopment hypothesis, i.e., software developers solve the same problems repeatedly; the oracle hypothesis, i.e., developers are able to predict variations from one redevelopment to others; and the organizational hypothesis, i.e., software must be organized according to behavior and structure to take advantage of the predictions that the developers make. The conceptual basis for reuse includes: program families, information hiding, abstract interfaces, uses and information hiding hierarchies, and process structure. The primary reusable software characteristics are black-box descriptions, structural descriptions, and composition and decomposition based on program families. Automated support can be provided for systematic reuse, and the Consortium is developing a prototype reuse library and guidebook. The software synthesis process that the Consortium is aiming toward includes modeling, refinement, prototyping, reuse, assessment, and new construction

    On the mechanism of carbon nanotube formation by means of catalytic chemical vapour deposition

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    Despite enormous strides in the synthesis of carbon nanotubes (CNTs), the mechanism for growth is still a highly debated issue. It is generally accepted that the model for carbon filament growth [1, 2], derived from concepts of vapour-liquid-solid theory, also applies to CNT growth. However, this model fails to account for the growth of CNTs from noble metal [3{7], ceramic [8, 9] and semiconducting nanoparticles [10{13], all of which are regarded as unable to catalyse the dissociation of hydrocarbons. In addition, in their bulk form, these materials do not have a catalytic function to produce graphite. This work examines non-traditional catalyst assisted chemical vapour deposition of CNTs with a view to determine the essential role of the catalyst in nanotube growth. CNT synthesis based upon noble metal and two approaches using germanium nanoparticles are presented. Extensive characterisation has been undertaken of each step of the growth process, and the synthesized carbon nanotubes are analysed by atomic force microscopy, electron microscopy and Raman spectroscopy. The results indicate that good densities of high quality single-walled carbon nanotubes are produced by these techniques. Additionally, the effects of different catalyst support interactions were explored by testing combinations of metal catalysts and support media. This study showed that the support has a strong effect on the chemical activity and morphology of the catalyst. The results presented show that the commonly utilised model of carbon filament growth is inadequate to describe CNT growth from non-traditional catalysts. A model for CNT growth consistent with the experimental results is proposed, in which the structural reorganisation of carbon to form CNTs is paramoun

    Synthesis of behavioral models from scenarios

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    Synthesis of FMSP Experience and Lessons Learned for Fisheries Co-Management, Final Technical Report

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    In November 2012, the UK Department for International Development (DFID) set the terms of reference for a commissioned assessment of fisheries and aquaculture science. The task was to complete a "scoping review", consisting of an in-depth assessment of the existing evidence related to fisheries and aquaculture activities in developing countries and their contribution to economic growth, food security and nutrition. For this the assessment was expected to identify the existing evidence and 'evidence in the pipeline' (i.e. to be published imminently) from the existing literature, compile it, and provide an assessment of the strength (in the sense, scientific rigor) of that evidence, and identify knowledge or evidence gaps. In addition the assessment was to be complemented by a mapping of existing relevant interventions in fisheries and aquaculture. In order to conduct this assessment, the team of consultants adopted a six step methodological protocol that allowed them to assess in a consistent manner the scientific quality of the documents included in the assessment, based on quality, size and consistency of the evidence. After scanning, 202 documents were retained. The main evidences from these 202 documents were organised under two main threads: (i) Developmental outcomes, including food security; nutrition; health; economic growth and (ii) Mediating factors focusing on governance; and gender

    The organisation and delivery of health improvement in general practice and primary care: a scoping study

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    Background This project examines the organisation and delivery of health improvement activities by and within general practice and the primary health-care team. The project was designed to examine who delivers these interventions, where they are located, what approaches are developed in practices, how individual practices and the primary health-care team organise such public health activities, and how these contribute to health improvement. Our focus was on health promotion and ill-health prevention activities. Aims The aim of this scoping exercise was to identify the current extent of knowledge about the health improvement activities in general practice and the wider primary health-care team. The key objectives were to provide an overview of the range and type of health improvement activities, identify gaps in knowledge and areas for further empirical research. Our specific research objectives were to map the range and type of health improvement activity undertaken by general practice staff and the primary health-care team based within general practice; to scope the literature on health improvement in general practice or undertaken by health-care staff based in general practice and identify gaps in the evidence base; to synthesise the literature and identify effective approaches to the delivery and organisation of health improvement interventions in a general practice setting; and to identify the priority areas for research as defined by those working in general practice. Methods We undertook a comprehensive search of the literature. We followed a staged selection process involving reviews of titles and abstracts. This resulted in the identification of 1140 papers for data extraction, with 658 of these papers selected for inclusion in the review, of which 347 were included in the evidence synthesis. We also undertook 45 individual and two group interviews with primary health-care staff. Findings Many of the research studies reviewed had some details about the type, process or location, or who provided the intervention. Generally, however, little attention is paid in the literature to examining the impact of the organisational context on the way services are delivered or how this affects the effectiveness of health improvement interventions in general practice. We found that the focus of attention is mainly on individual prevention approaches, with practices engaging in both primary and secondary prevention. The range of activities suggests that general practitioners do not take a population approach but focus on individual patients. However, it is clear that many general practitioners see health promotion as an integral part of practice, whether as individual approaches to primary or secondary health improvement or as a practice-based approach to improving the health of their patients. Our key conclusion is that there is currently insufficient good evidence to support many of the health improvement interventions undertaken in general practice and primary care more widely. Future Research Future research on health improvement in general practice and by the primary health-care team needs to move beyond clinical research to include delivery systems and be conducted in a primary care setting. More research needs to examine areas where there are chronic disease burdens – cancer, dementia and other disabilities of old age. Reviews should be commissioned that examine the whole prevention pathway for health problems that are managed within primary care drawing together research from general practice, pharmacy, community engagement, etc

    Improving Community Adaptation Outcomes for Youth Graduating from Residential Mental Health Programs: A Synthesis Review (SUMMARY)

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    The focus of this synthesis review was to understand the capacity of systems of care and integrated program models to foster successful community adaptation for children and youth graduating from children\u27s residential mental health treatment

    A systematic review of whole class, subject based, pedagogies with reported outcomes for the academic and social inclusion of pupils with special educational needs in mainstream classrooms

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    Schools across the world have responded to international and national initiatives designed to further the development of inclusive education. In England, there is a statutory requirement for all schools to provide effective learning opportunities for all pupils (QCA, 2000) and children with special educational needs (SEN) are positioned as having a right to be within mainstream classrooms accessing an appropriate curriculum (SENDA, 2001). Previous reviews which have sought to identify classroom practices that support the inclusion of children with SEN have been technically non-systematic and hence a need for a systematic review within this area has been identified (Nind et al., 2004; Rix et al., 2006). This systematic literature review is the last in a series of three
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