10,401 research outputs found

    Design and evaluation of a smart library using the APEX framework

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    User experience is a key point for successful ubiquitous computing (ubicomp) environments. The envisaged design should be explored as soon as possible to anticipate potential user problems, thus reducing re-design costs. The development of ubicomp environments' prototypes might help, providing feedback on the users' reaction to the environments. This paper describes the design and evaluation of ubicomp environments using APEX, a rapid prototyping framework providing user experience via a 3D application server and connected physical devices. APEX prototypes allow users to explore and experience many characteristics of a proposed design, in a virtual world. The paper focus in particular the design and evaluation of a smart library in the APEX framework.(undefined

    Formal analysis of ubiquitous computing environments through the APEX framework

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    Ubiquitous computing (ubicomp) systems involve complex interactions between multiple devices and users. This com-plexity makes it difficult to establish whether: (1) observa-tions made about use are truly representative of all possible interactions; (2) desirable characteristics of the system are true in all possible scenarios. To address these issues, tech-niques are needed that support an exhaustive analysis of a system’s design. This paper demonstrates one such exhaus-tive analysis technique that supports the early evaluation of alternative designs for ubiquitous computing environments. The technique combines models of behavior within the environment with a virtual world that allows its simulation. The models support checking of properties based on pat-terns. These patterns help the analyst to generate and verify relevant properties. Where these properties fail then scenar-ios suggested by the failure provide an important aid to redesign. The proposed technique uses APEX, a framework for rapid prototyping of ubiquitous environments based on Petri nets. The approach is illustrated through a smart li-brary example. Its benefits and limitations are discussed.(undefined

    In-Vivo Bytecode Instrumentation for Improving Privacy on Android Smartphones in Uncertain Environments

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    In this paper we claim that an efficient and readily applicable means to improve privacy of Android applications is: 1) to perform runtime monitoring by instrumenting the application bytecode and 2) in-vivo, i.e. directly on the smartphone. We present a tool chain to do this and present experimental results showing that this tool chain can run on smartphones in a reasonable amount of time and with a realistic effort. Our findings also identify challenges to be addressed before running powerful runtime monitoring and instrumentations directly on smartphones. We implemented two use-cases leveraging the tool chain: BetterPermissions, a fine-grained user centric permission policy system and AdRemover an advertisement remover. Both prototypes improve the privacy of Android systems thanks to in-vivo bytecode instrumentation.Comment: ISBN: 978-2-87971-111-

    The APEX framework: prototyping of ubiquitous environments based on Petri Nets

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    The user experience of ubiquitous environments is a determining factor in their success. The characteristics of such systems must be explored as early as possible to anticipate potential user problems, and to reduce the cost of redesign. However, the development of early prototypes to be evaluated in the target environment can be disruptive to the ongoing system and therefore unacceptable. This paper reports on an ongoing effort to explore how model-based rapid prototyping of ubiquitous environments might be used to avoid actual deployment while still enabling users to interact with a representation of the system. The paper describes APEX, a framework that brings together an existing 3D Application Server with CPN Tools. APEX-based prototypes enable users to navigate a virtual world simulation of the envisaged ubiquitous environment. The APEX architecture and the proposed CPN-based modelling approach are described. An example illustrates their use.Fundação para a Ciência e a Tecnologia (FCT) - bolsa de doutoramento SFRH/BD/41179/200

    Immersiveness of ubiquitous computing environments prototypes: A case study

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    The development of ubiquitous computing (ubicomp) environments raises several challenges in terms of their evaluation. Ubicomp virtual reality prototyping tools enable users to experience the system to be developed and are of great help to face those challenges, as they support developers in assessing the consequences of a design decision in the early phases of development. Given the situated nature of ubicomp environments, a particular issue to consider is the level of realism provided by the prototypes. This work presents a case study where two ubicomp prototypes, featuring different levels of immersion (desktop-based versus CAVE-based), were developed and compared. The goal was to determine the cost/benefits relation of both solutions, which provided better user experience results, and whether or not simpler solutions provide the same user experience results as more elaborate one.Fundação para a Ciência e a Tecnologia (FCT) through Projecto Estratégico – LA 9 – 2014-2015 (PEst-OE/EEI/LA0009/201

    Supporting the design of an ambient assisted living system using virtual reality prototypes

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    APEX, a framework for prototyping ubiquitous environments, is used to design an Ambient Assisted Living (AAL) system to enhance a care home for older people. The environment allows participants in the design process to experience the proposed design and enables developers to explore the design by rapidly developing alternatives. APEX provided the means to explore alternative designs through a virtual environment. It provides a mediating representation (a boundary object) allowing users to be involved in the design process. A group of residents in a city-based care home were involved in the design. The paper describes the design process and lessons learnt for the design of AAL systems.EPSRC - Engineering and Physical Sciences Research Council(EP/G059063/1)Jose C. Campos acknowledges support by the FCT – Fundação para a Ciência e a Tecnologia (Portuguese Foundation for Science and Technology) within project UID/EEA/50014/2013. José Luís Silva acknowledges support from project PEST-OE/EEI/LA0009/2015. Michael Harrison was also funded by EPSRC research grant EP/G059063/1: CHI+MED (Computer–Human Interaction for Medical Devices)

    Supporting the design of an ambient assisted living system using virtual reality prototypes

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    APEX, a framework for prototyping ubiquitous environments, is used to design an Ambient Assisted Living (AAL) system to enhance a care home for older people. The environment allows participants in the design process to experience the proposed design and enables developers to explore the design by rapidly developing alternatives. APEX provided the means to explore alternative designs through a virtual environment. It provides a mediating representation (a boundary object) allowing users to be involved in the design process. A group of residents in a city-based care home were involved in the design. The paper describes the design process and lessons learnt for the design of AAL systems.info:eu-repo/semantics/acceptedVersio

    Giving credit to reforestation for water quality benefits.

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    While there is a general belief that reforesting marginal, often unprofitable, croplands can result in water quality benefits, to date there have been very few studies that have attempted to quantify the magnitude of the reductions in nutrient (N and P) and sediment export. In order to determine the magnitude of a credit for water quality trading, there is a need to develop quantitative approaches to estimate the benefits from forest planting in terms of load reductions. Here we first evaluate the availability of marginal croplands (i.e. those with low infiltration capacity and high slopes) within a large section of the Ohio River Basin (ORB) to assess the magnitude of the land that could be reforested. Next, we employ the Nutrient Tracking Tool (NTT) to study the reduction in N, P and sediment losses from converting corn or corn/soy rotations to forested lands, first in a case study and then for a large region within the ORB. We find that after reforestation, N losses can decrease by 40 to 80 kg/ha-yr (95-97% reduction), while P losses decrease by 1 to 4 kg/ha-yr (96-99% reduction). There is a significant influence of local conditions (soils, previous crop management practices, meteorology), which can be considered with NTT and must be taken into consideration for specific projects. There is also considerable interannual and monthly variability, which highlights the need to take the longer view into account in nutrient credit considerations for water quality trading, as well as in monitoring programs. Overall, there is the potential for avoiding 60 million kg N and 2 million kg P from reaching the streams and rivers of the northern ORB as a result of conversion of marginal farmland to tree planting, which is on the order of 12% decrease for TN and 5% for TP, for the entire basin. Accounting for attenuation, this represents a significant fraction of the goal of the USEPA Gulf of Mexico Hypoxia Task Force to reduce TN and TP reaching the dead zone in the Gulf of Mexico, the second largest dead zone in the world. More broadly, the potential for targeted forest planting to reduce nutrient loading demonstrated in this study suggests further consideration of this approach for managing water quality in waterways throughout the world. The study was conducted using computational models and there is a need to evaluate the results with empirical observations

    An infrastructure for experience centered agile prototyping of ambient intelligence

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    Ubiquitous computing poses new usability challenges that cut across design and development. We are particularly interested in "spaces" enhanced with sensors, public displays and personal devices. How can prototypes be used to explore the user's mobility and interaction, both explicitly and implicitly, to access services within these environments? Because of the potential cost of development and design failure, the characteristics of such systems must be explored using early versions of the system that could disrupt if used in the target environment. Being able to evaluate these systems early in the process is crucial to their successful development. This paper reports on an effort to develop a framework for the rapid prototyping and analysis of ambient intelligence systems
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