986 resultados para Final user
Resumo:
We introduce a lightweight biometric solution for user authentication over networks using online handwritten signatures. The algorithm proposed is based on a modified Hausdorff distance and has favorable characteristics such as low computational cost and minimal training requirements. Furthermore, we investigate an information theoretic model for capacity and performance analysis for biometric authentication which brings additional theoretical insights to the problem. A fully functional proof-of-concept prototype that relies on commonly available off-the-shelf hardware is developed as a client-server system that supports Web services. Initial experimental results show that the algorithm performs well despite its low computational requirements and is resilient against over-the-shoulder attacks.
Resumo:
The IEEE Wireless LAN standard has been a true success story by enabling convenient, efficient and low-cost access to broadband networks for both private and professional use. However, the increasing density and uncoordinated operation of wireless access points, combined with constantly growing traffic demands have started hurting the users' quality of experience. On the other hand, the emerging ubiquity of wireless access has placed it at the center of attention for network attacks, which not only raises users' concerns on security but also indirectly affects connection quality due to proactive measures against security attacks. In this work, we introduce an integrated solution to congestion avoidance and attack mitigation problems through cooperation among wireless access points. The proposed solution implements a Partially Observable Markov Decision Process (POMDP) as an intelligent distributed control system. By successfully differentiating resource hampering attacks from overload cases, the control system takes an appropriate action in each detected anomaly case without disturbing the quality of service for end users. The proposed solution is fully implemented on a small-scale testbed, on which we present our observations and demonstrate the effectiveness of the system to detect and alleviate both attack and congestion situations.
Resumo:
News blog hot topics are important for the information recommendation service and marketing. However, information overload and personalized management make the information arrangement more difficult. Moreover, what influences the formation and development of blog hot topics is seldom paid attention to. In order to correctly detect news blog hot topics, the paper first analyzes the development of topics in a new perspective based on W2T (Wisdom Web of Things) methodology. Namely, the characteristics of blog users, context of topic propagation and information granularity are unified to analyze the related problems. Some factors such as the user behavior pattern, network opinion and opinion leader are subsequently identified to be important for the development of topics. Then the topic model based on the view of event reports is constructed. At last, hot topics are identified by the duration, topic novelty, degree of topic growth and degree of user attention. The experimental results show that the proposed method is feasible and effective.
Resumo:
This paper aims to inform design strategies for smart space technology to enhance libraries as environments for co-working and informal social learning. The focus is on understanding user motivations, behaviour, and activities in the library when there is no programmed agenda. The study analyses gathered data over five months of ethnographic research at ‘The Edge’ – a bookless library space at the State Library of Queensland in Brisbane, Australia, that is explicitly dedicated to co-working, social learning, peer collaboration, and creativity around digital culture and technology. The results present five personas that embody people’s main usage patterns as well as motivations, attitudes, and perceived barriers to social learning. It appears that most users work individually or within pre-organised groups, but usually do not make new connections with co-present, unacquainted users. Based on the personas, four hybrid design dimensions are suggested to improve the library as a social interface for shared learning encounters across physical and digital spaces. The findings in this paper offer actionable knowledge for managers, decision makers, and designers of technology-enhanced library spaces and similar collaboration and co-working spaces.
Resumo:
There are different ways to authenticate humans, which is an essential prerequisite for access control. The authentication process can be subdivided into three categories that rely on something someone i) knows (e.g. password), and/or ii) has (e.g. smart card), and/or iii) is (biometric features). Besides classical attacks on password solutions and the risk that identity-related objects can be stolen, traditional biometric solutions have their own disadvantages such as the requirement of expensive devices, risk of stolen bio-templates etc. Moreover, existing approaches provide the authentication process usually performed only once initially. Non-intrusive and continuous monitoring of user activities emerges as promising solution in hardening authentication process: iii-2) how so. behaves. In recent years various keystroke dynamic behavior-based approaches were published that are able to authenticate humans based on their typing behavior. The majority focuses on so-called static text approaches, where users are requested to type a previously defined text. Relatively few techniques are based on free text approaches that allow a transparent monitoring of user activities and provide continuous verification. Unfortunately only few solutions are deployable in application environments under realistic conditions. Unsolved problems are for instance scalability problems, high response times and error rates. The aim of this work is the development of behavioral-based verification solutions. Our main requirement is to deploy these solutions under realistic conditions within existing environments in order to enable a transparent and free text based continuous verification of active users with low error rates and response times.
An evaluation of the Australian Capital Territory Sexual Assault Reform Program (SARP): Final Report
Resumo:
In 2005 the Australian Capital Territory (ACT) Office of the Director of Public Prosecutions (DPP) and the Australian Federal Police (AFP) produced a report, Responding to sexual assault: The challenge of change (DPP & AFP 2005), which made 105 recommendations for reforming the way sexual offence cases are handled by the ACT’s criminal justice system. The Sexual Assault Reform Program (SARP) is one key initiative developed in response to these recommendations. Managed by the ACT Justice and Community Safety Directorate (JACS), SARP’s main objective is to improve aspects of the criminal justice system relating to: processes and support for victims of sexual offences as they progress through the system; attrition in sexual offence matters in the criminal justice system; and coordination and collaboration among the agencies involved. In November 2007 the ACT Attorney-General announced $4 million of funding for several SARP reforms. This funding provided for additional victim support staff; a dedicated additional police officer, prosecutor and legal policy officer; and an upgrade of equipment for the Supreme Court and Magistrates Court, including improvements in technology to assist witnesses in giving evidence, and the establishment of an off-site facility to allow witnesses to give evidence from a location outside of the court. In addition, the reform agenda included a number of legislative amendments that changed how evidence can be given by victims of sexual and family violence offences, children and other vulnerable witnesses. The primary objectives of these legislative changes are to provide an unintimidating, safe environment for vulnerable witnesses (including sexual offence complainants) to give evidence and to obtain prompt statements from witnesses to improve the quality of evidence captured (DPP 2009: 13). The current evaluation The funding for SARP reforms also provided for a preliminary evaluation of the reforms; this report outlines findings from the evaluation. The evaluation sought to address whether the program has met its key objectives: better support for victims, lower attrition rates and improved coordination and collaboration among agencies involved in administering SARP. The evaluation was conducted in two stages and involved a mixed-methods approach. During stage 1 key indicators for the evaluation were developed with stakeholders. During stage 2 quantitative data were collected by stakeholders and provided to the AIC for analysis. Qualitative interviews were also conducted with service delivery providers, and with a small number (n=5) of victim/survivors of sexual offences whose cases had recently been resolved in the ACT criminal justice system. The current evaluation is preliminary in nature. As the SARP reforms will take time to become entrenched within the ACT’s criminal justice system, some of the impacts of the reforms may not yet be evident. Nonetheless, this evaluation provides an insight into how well the SARP reforms have been implemented to date, as well as key areas that could be addressed in the future. Key findings from the preliminary evaluation are outlined briefly below.
Resumo:
The Australian Business Assessment of Computer User Security (ABACUS) survey is a nationwide assessment of the prevalence and nature of computer security incidents experienced by Australian businesses. This report presents the findings of the survey which may be used by businesses in Australia to assess the effectiveness of their information technology security measures.
Resumo:
The project 'Good practice for safeguarding student learning engagement in higher education institutions' commenced in late 2010 as a Competitive Grant with funding provided by the Australian Learning and Teaching Council. The project is now overseen by the Office for Learning and Teaching within the Australian Department of Industry, Innovation, Science, Research and Tertiary Education. The project was completed in December 2012. The project was lead by QUT and comprised of the project team: Professor Karen Nelson, (project leader), Ms Tracy Creagh, (project manager) and Adjunct Professor John Clarke. Commencing in late 2010 the project invited a total of eight institutions across Australia and New Zealand (including QUT) who had either: existing programs and activities that monitored student learning engagement (MSLE); were in the early stages of implementing MSLE programs, or; who were piloting MSLE activities. As well, the project involved an advisory group and project evaluator comprising of academic and professional staff across two additional universities.
Resumo:
The increasing demand for mobile video has attracted much attention from both industry and researchers. To satisfy users and to facilitate the usage of mobile video, providing optimal quality to the users is necessary. As a result, quality of experience (QoE) becomes an important focus in measuring the overall quality perceived by the end-users, from the aspects of both objective system performance and subjective experience. However, due to the complexity of user experience and diversity of resources (such as videos, networks and mobile devices), it is still challenging to develop QoE models for mobile video that can represent how user-perceived value varies with changing conditions. Previous QoE modelling research has two main limitations: aspects influencing QoE are insufficiently considered; and acceptability as the user value is seldom studied. Focusing on the QoE modelling issues, two aims are defined in this thesis: (i) investigating the key influencing factors of mobile video QoE; and (ii) establishing QoE prediction models based on the relationships between user acceptability and the influencing factors, in order to help provide optimal mobile video quality. To achieve the first goal, a comprehensive user study was conducted. It investigated the main impacts on user acceptance: video encoding parameters such as quantization parameter, spatial resolution, frame rate, and encoding bitrate; video content type; mobile device display resolution; and user profiles including gender, preference for video content, and prior viewing experience. Results from both quantitative and qualitative analysis revealed the significance of these factors, as well as how and why they influenced user acceptance of mobile video quality. Based on the results of the user study, statistical techniques were used to generate a set of QoE models that predict the subjective acceptability of mobile video quality by using a group of the measurable influencing factors, including encoding parameters and bitrate, content type, and mobile device display resolution. Applying the proposed QoE models into a mobile video delivery system, optimal decisions can be made for determining proper video coding parameters and for delivering most suitable quality to users. This would lead to consistent user experience on different mobile video content and efficient resource allocation. The findings in this research enhance the understanding of user experience in the field of mobile video, which will benefit mobile video design and research. This thesis presents a way of modelling QoE by emphasising user acceptability of mobile video quality, which provides a strong connection between technical parameters and user-desired quality. Managing QoE based on acceptability promises the potential for adapting to the resource limitations and achieving an optimal QoE in the provision of mobile video content.
Resumo:
We propose a multi-layer spectrum sensing optimisation algorithm to maximise sensing efficiency by computing the optimal sensing and transmission durations for a fast changing, dynamic primary user. Dynamic primary user traffic is modelled as a random process, where the primary user changes states during both the sensing period and transmission period to reflect a more realistic scenario. Furthermore, we formulate joint constraints to correctly reflect interference to the primary user and lost opportunity of the secondary user during the transmission period. Finally, we implement a novel duty cycle based detector that is optimised with respect to PU traffic to accurately detect primary user activity during the sensing period. Simulation results show that unlike currently used detection models, the proposed algorithm can jointly optimise the sensing and transmission durations to simultaneously satisfy the optimisation constraints for the considered primary user traffic.
Resumo:
A key issue in the field of inclusive design is the ability to provide designers with an understanding of people's range of capabilities. Since it is not feasible to assess product interactions with a large sample, this paper assesses a range of proxy measures of design-relevant capabilities. It describes a study that was conducted to identify which measures provide the best prediction of people's abilities to use a range of products. A detailed investigation with 100 respondents aged 50-80 years was undertaken to examine how they manage typical household products. Predictor variables included self-report and performance measures across a variety of capabilities (vision, hearing, dexterity and cognitive function), component activities used in product interactions (e.g. using a remote control, touch screen) and psychological characteristics (e.g. self-efficacy, confidence with using electronic devices). Results showed, as expected, a higher prevalence of visual, hearing, dexterity, cognitive and product interaction difficulties in the 65-80 age group. Regression analyses showed that, in addition to age, performance measures of vision (acuity, contrast sensitivity) and hearing (hearing threshold) and self-report and performance measures of component activities are strong predictors of successful product interactions. These findings will guide the choice of measures to be used in a subsequent national survey of design-relevant capabilities, which will lead to the creation of a capability database. This will be converted into a tool for designers to understand the implications of their design decisions, so that they can design products in a more inclusive way.
Resumo:
In this research fluidization behavior of cubical Bovine intestine samples was studied. Bovine intestine samples were heat pump dried at atmospheric pressure and at emperatures below and above the material freezing points. Experiments were conducted to study fluidization characteristics and drying kinetics at different drying conditions. Bovine particles were characterized according to Geldart classification and minimum fluidization velocity was calculated using Ergun Equation and generalized equation for all drying conditions at the beginning of the trials and end of the trials. Walli’s model was used to categorize stability of the fluidization at the beginning and end of the drying for each trial. Walli’s values determined were positive at the beginning and end of all trials indicating stable fluidisation at the beginning and end for each drying condition.
Resumo:
We report inelastic neutron scattering measurements of the neutron Compton profile, J(y), for Be and for D in polycrystalline ZrD2 over a range of momentum transfers, q between 27 and 178 °A−1. The measurements were performed using the inverse geometry spectrometer eVS which is situated at the UK pulsed spallation neutron source ISIS. We have investigated deviations from impulse approximation (IA) scattering which are generically referred to as final state effects (FSEs) using a method described by Sears. This method allows both the magnitude and the q dependence of the FSE to be studied. Analysis of the measured data was compared with analysis of numerical simulations based on the harmonic approximation and good agreement was found for both ZrD2 and Be. Finally we have shown how (∇2V), where V is the interatomic potential, can be extracted from the antisymmetric component of J(y).
Unpacking user relations in an emerging ubiquitous computing environment : introducing the bystander
Resumo:
The move towards technological ubiquity is allowing a more idiosyncratic and dynamic working environment to emerge that may result in the restructuring of information communication technologies, and changes in their use through different user groups' actions. Taking a ‘practice’ lens to human agency, we explore the evolving roles of, and relationships between these user groups and their appropriation of emergent technologies by drawing upon Lamb and Kling's social actor framework. To illustrate our argument, we draw upon a study of a UK Fire Brigade that has introduced a variety of technologies in an attempt to move towards embracing mobile and ubiquitous computing. Our analysis of the enactment of such technologies reveals that Bystanders, a group yet to be taken as the central unit of analysis in information systems research, or considered in practice, are emerging as important actors. The research implications of our work relate to the need to further consider Bystanders in deployments other than those that are mobile and ubiquitous. For practice, we suggest that Bystanders require consideration in the systems development life cycle, particularly in terms of design and education in processes of use.