Agent-based architectural framework enhancing configurability,autonomy and scalability of context-aware pervasive services

Multi-agent software architectures have gained in popularity due to their beneficial behavior in designing and implementing sophisticated applications. However, current approaches in implementing such architectures have led to application-specific, non-scalable implementations which limit the reusablity and improvement of the whole architecture. Moreover, these attempts lack features to enhance the user experience, thus slowing the adoption of the resulting services. In this paper we describe a fully-fledged multi-agent architecture covering a large variety of preferred features including capabilities of ‘plugging’ ubiquitous services, servicing mobile users, interconnecting remote similar architectures and interfacing with advanced software components such as knowledge bases. This framework exploits a wide-range of context-aware components making it essentially context-aware, allowing for the development of ubiquitous context-aware human-centric services, which are the focus of our research. To illustrate the flexibility of this architectural framework, we present four services which were built using this architectural paradigm by different development teams and elaborate on their overall behavior.     

Harnessing Cloud Technologies for a Virtualized Distributed Computing Infrastructure

The InterGrid system aims to provide an execution environment for running applications on top of interconnected infrastructures. The system uses virtual machines as building blocks to construct execution environments that span multiple computing sites. Such environments can be extended to operate on cloud infrastructures, such as Amazon EC2. This article provides an abstract view of the proposed architecture and its implementation; experiments show the scalability of an InterGrid-managed infrastructure and how the system can benefit from using the cloud.     

Learning Complex Tasks Using a Stepwise Approach

This paper explores a stepwise learning approach based on a system's decomposition into functional subsystems. Two case studies are examined: a visually guided robot that learns to track a maneuvering object, and a robot that learns to use the information from a force sensor in order to put a peg into a hole. These two applications show the features and advantages of the proposed approach: i) the subsystems naturally arise as functional components of the hardware and software; ii) these subsystems are building blocks of the robot behavior and can be combined in several ways for performing various tasks; iii) this decomposition makes it easier to check the performances and detect the cause of a malfunction; iv) only those subsystems for which a satisfactory solution is not available need to be learned; v) the strategy proposed for coordinating the optimization of all subsystems ensures an improvement at the task-level; vi) the overall system's behavior is significantly improved by the stepwise learning approach.     

Better Living Through Geometry

Mark Weiser described ubiquitous computing as “invisible, everywhere computing that does not live on a personal device of any sort, but is in the woodwork everywhere”[1]. The EasyLiving project is concerned with development of an architecture and technologies for ubiquitous computing environments that allow the dynamic aggregation of diverse I/O devices into a single coherent user experience. Though the need for research in distributed computing, perception and interfaces is widely recognised, the importance of an explicit geometric world model for enhancing the user’s experience of a ubiquitous computing system has not been well-articulated. This paper describes three scenarios that benefit from geometric context and introduces the EasyLiving Geometric Model.     

Self-organizable panel for assembling DIY ubiquitous computing

This paper proposes the concept of DIY (do-it-yourself) ubiquitous computing, an architecture allowing non-experts to establish ubiquitous computing environments in the real world. This concept has been implemented in the “u-Texture”, which is a self-organizable panel that works as a building block. While the traditional scheme attaches devices such as computers, sensors, and network equipments externally to make everyday objects smart, the u-Texture has these devices built in beforehand to assemble smart objects. The u-Texture can change its own behavior autonomously through recognition of its location, its angle of inclination, and surrounding environment by assembling these factors physically. This paper describes the design, the implementation, and various applications of u-Textures to confirm that the concept can contribute to establishment of ubiquitous computing environments in the real world without expert users.     

The software architecture of a distributed problem‐solving environment

This paper describes the functionality and software architecture of a generic problem‐solving environment (PSE) for collaborative computational science and engineering. A PSE is designed to provide transparent access to heterogeneous distributed computing resources, and is intended to enhance research productivity by making it easier to construct, run, and analyze the results of computer simulations. Although implementation details are not discussed in depth, the role of software technologies such as CORBA, Java, and XML is outlined. An XML‐based component model is presented. The main features of a Visual Component Composition Environment for software development, and an Intelligent Resource Management System for scheduling components, are described. Some prototype implementations of PSE applications are also presented. Copyright © 2000 John Wiley & Sons, Ltd.     

Personalization and Context Management

Supporting the individual user in his working, learning, or information access is one of the main goals of user modeling. Personal or group user models make it possible to represent and use information about preferences, knowledge, abilities, emotional states, and many other characteristics of a user to adapt the user experience and support. Nowadays, the disappearing computer enables the user to access her information from a variety of personal and public displays and devices. To support a new generation of contextualized and personalized information and services, this paper addresses the problem of context management. Context management is a new approach to the design of context-aware systems in ubiquitous computing that combines personalization and contextualization. The presented framework for context management integrates user modeling and context modeling, which can benefit from each other and give rise to more valid models for personalized and contextualized information delivery. The paper will introduce a base framework and tools for designing context-aware applications and decompose the underlying framework into its foundational components. As two illustrative application cases, the paper discusses implementations of an intelligent advertisement board and an audio-augmented museum environment.     

Extending tuplespaces for coordination in interactive workspaces

The current interest in programming models and software infrastructures to support ubiquitous and environmental computing is heightened by the falling cost of hardware and the ubiquity of local-area wireless networking technologies. Interactive workspaces are technologically augmented team-project rooms that represent a specific sub-domain of ubiquitous computing. We argue both from related work and from our own experience with a prototype that the tuplespace model of communication forms the best basis for a coordination infrastructure for such workspaces. This paper presents the usage and characteristics expected of interactive workspaces, from which we derive a set of key system properties for any coordination infrastructure in an interactive workspace. We show that the design aspects of tuplespaces, augmented with some new extensions, yield a system model, which we call the Event Heap, that satisfies all of the desired properties. We also briefly discuss why other coordination models fall short of the desired properties, and describe our experience using our implementation of the Event Heap model. The paper focuses on a justification of the use of tuplespaces in interactive workspaces, and does not provide a detailed discussion of the Event Heap implementation or our more general experience with interactive workspaces, each of which is treated in detail elsewhere.     

openModeller: a generic approach to species’ potential distribution modelling

Species’ potential distribution modelling is the process of building a representation of the fundamental ecological requirements for a species and extrapolating these requirements into a geographical region. The importance of being able to predict the distribution of species is currently highlighted by issues like global climate change, public health problems caused by disease vectors, anthropogenic impacts that can lead to massive species extinction, among other challenges. There are several computational approaches that can be used to generate potential distribution models, each achieving optimal results under different conditions. However, the existing software packages available for this purpose typically implement a single algorithm, and each software package presents a new learning curve to the user. Whenever new software is developed for species’ potential distribution modelling, significant duplication of effort results because many feature requirements are shared between the different packages. Additionally, data preparation and comparison between algorithms becomes difficult when using separate software applications, since each application has different data input and output capabilities. This paper describes a generic approach for building a single computing framework capable of handling different data formats and multiple algorithms that can be used in potential distribution modelling. The ideas described in this paper have been implemented in a free and open source software package called openModeller. The main concepts of species’ potential distribution modelling are also explained and an example use case illustrates potential distribution maps generated by the framework.     

Technologies for ubiquitous supercomputing: a Java interface to the Nexus communication system

We use the term ubiquitous supercomputing to refer to systems that integrate low- and mid-range computing systems, advanced networks and remote high-end computers with the goal of enhancing the computational power accessible from local environments. Such systems promise to enable new applications in areas as diverse as smart instruments and collaborative environments. However, they also demand tools for transporting code between computers and for establishing flexible, dynamic communication structures. In this article, we propose that these requirements be satisfied by introducing Java classes that implement the global pointer and remote service request mechanisms defined by a communication library called Nexus. Java supports transportable code; Nexus provides communication support and represents the core communication framework for Globus, a project building infrastructure for ubiquitous supercomputing. We explain how this NexusJava library is implemented and illustrate its use with examples. © 1997 John Wiley & Sons, Ltd.     

Consistent Modelling of Users, Devices and Sensors in a Ubiquitous Computing Environment

This paper describes the use of an accretion-resolution user modelling representation to model people, places and objects. We explain the motivation for the key properties of the representation, especially those of particular importance for ubiquitous computing: firstly, for flexibility in interpreting the typically noisy and potentially conflicting evidence about users’ locations; secondly, to support users in scrutinising their user model, the processes that determine its contents and the way that it is used in the ubiquitous computing environment. A novel and important aspect of this work is our extension of the representation beyond modelling just users, using it also to represent the other elements such as devices, sensors, rooms and buildings. We illustrate our approach in terms of models we have been building for a system which enables users to gain personalised information about the sensors and services in a ubiquitous computing environment. We report experiments on the scalability and the management of inconsistency in modelling of location, based on accretion-resolution     

Paratyping: A Contextualized Method of Inquiry for Understanding Perceptions of Mobile and Ubiquitous Computing Technologies

In this article, we describe the origins, use, and efficacy of a contextualized method for evaluating mobile and ubiquitous computing systems. This technique, which we called paratyping, is based on experience prototyping and event-contingent experience sampling and allows researchers to survey people in real-life situations without the need for costly and sometimes untenable deployment evaluations. We used this tool to probe the perceptions of the conversation partners of users of the Personal Audio Loop, a memory aid with the potential for substantial privacy implications. Based on that experience, we refined and adapted the approach to evaluate SenseCam, a wearable, automatic picture-taking device, across multiple geographic locations. We describe the benefits, challenges, and methodological considerations that emerged during our use of the paratyping method across these two studies. We describe how this method blends some of the benefits of survey-based research with more contextualized methods, focusing on trustworthiness of the method in terms of generating scientific knowledge. In particular, this method is a good fit for studying certain classes of mobile and ubiquitous computing applications but can be applied to many types of applications.     

Using mobile code to build a smart kitchen

Software infrastructures for handheld and ubiquitous computing systems help developers tackle many implementation problems. Sun Microsystems recently introduced an infrastructure called Jini. We report on our experiences of using Jini to build a smart kitchen. We found that the central Jini concept of code mobility proved very beneficial offering a simple mechanism for device interoperability and encouraging developers to better structure the software.     

Improving media services on P2P networks

The Media Accelerating Peer Services system extends P2P infrastructures to improve multimedia services across heterogeneous computing platforms. In this article, we present an architecture and resource management and adaptation framework that transcends existing infrastructures to accommodate and accelerate multimedia peer applications and services. We also propose key technology components that support seamless adaptation of resources to enhance quality of service and the building of better tools and applications that utilize the peer-computing network's underlying power     

On the Characterization and Risk Assessment of AI-Powered Mobile Cloud Applications

Ultra-reliable low-latency communication supports powerful mission-critical applications such as artificial intelligence-enabled mobile cloud applications designed to deliver the quality of service and quality of experience to their users. However, whether existing security mechanisms are ready to address the risks emerging from these applications operating over ultra-fast 5G and 6G infrastructures is an open question. The complexity of finding answers to this question is partly due to the lack of means to measure software applications’ intelligence levels and partly due to the limitations of existing risk assessment approaches. In this paper, first, we propose an ability-based scale to characterize intelligent software applications. After that, we propose a semi-quantitative approach for threat modeling and risk analysis of intelligent software applications. Focusing on Android, we define three intelligent mobile cloud applications’ scenarios and demonstrate the feasibility of the proposed scale and approach. We perform their risk analyses for assessing the readiness of Android security mechanisms to mitigate their risks and identify open problems. We propose to rethink intelligent mobile cloud computing applications’ characterization and warn security experts to redesign their security mechanisms to serve evolving privacy, security, and trust requirements.     

Towards a framework to characterize ubiquitous software projects

ContextUbiquitous Computing (or UbiComp) represents a paradigm in which information processing is thoroughly integrated into everyday objects and activities. From a Software Engineering point of view this development scenario brings new challenges in tailoring or building software processes, impacting current software technologies. However, it has not yet been explicitly shown how to characterize a software project with the perception of ubiquitous computing.ObjectiveThis paper presents a conceptual framework to support the characterization of ubiquitous software projects according to their ubiquity adherence level. It also intends to apply such characterization approach to some projects, aiming at observing their adherence with ubiquitous computing principles.MethodTo follow a research strategy based on systematic reviews and surveys to acquire UbiComp knowledge and organize a conceptual framework regarding ubiquitous computing, which can be used to characterize UbiComp software projects. Besides, to demonstrate its application by characterizing some software projects.ResultsUbiquitous computing encapsulates at least 11 different high abstraction level characteristics represented by 123 functional and 45 restrictive factors. Based on this a checklist was organized to allow the characterization of ubiquitous software projects, which has been applied on 26 ubiquitous software projects from four different application domains (ambient intelligence, pervasive healthcare, U-learning, and urban space). No project demonstrated to support more than 65% of the characteristics set. Service omnipresence was observed in all of these projects. However, some characteristics, although identified as necessary in the checklist, were not identified in any of them.ConclusionThere are characteristics that identify a software project as ubiquitous. However, a ubiquitous software project does not necessarily have to implement all of them. The application domain can influence the appearing of UbiComp characteristics in software projects, promoting an increase of their adherence to UbiComp and, thus, for additional software technologies to deal with these ubiquitous requirements.     

Multi-agent systems for protecting critical infrastructures: A survey

Multi-agent systems have emerged as a very significant platform in provisioning distributed and collaborative services to critical applications. Such applications require ubiquitous agent presence in the environment for monitoring, collecting data, communication, and subsequent data analysis, where the sensitivity of the application's nature cannot be understated. Recent advances in the field of autonomous, ubiquitous, intelligent and distributed computing have led to corresponding developments in the use of collaborating multi-agents to protect critical infrastructures. Such systems have witnessed crucial demand for deployment in diverse application scenarios such as E-commerce, E-health, Network Intrusion Detection, Telematics and Transport Systems, Environmental Monitoring, as well as for distributed information processing in general. Critical infrastructures have longed for a distributed system in place for their uninterrupted and accurate operations. Multi-agents have provided one such approach towards addressing the issue of protecting such infrastructures through collaborative and distributed information processing. In this paper, a state-of-the-art on the use of multi-agent based systems for protecting five most common critical infrastructures, is presented.     

Assessing the Usability of a Science Gateway for Medical Knowledge Bases with TRENCADIS

Biomedical applications are often built on top of knowledge bases that contain medical images and clinical reports. Currently, these bases are being used to improve diagnosis, research and teaching, but in many cases, the infrastructure required has a prohibitive cost for many medical centres. However, resources can be attached from existing e-Science infrastructures. Therefore, many efforts have been made to establish best practices that allow the use of such infrastructures. However, e-Science relies on open, distributed, collaborative environments, built on top of very specialized technologies, such as Grid and Cloud computing, which require reasonable technical skills for their usage. Therefore, science gateways have become essential tools that assist users in interacting with e-Science applications. This paper describes TRENCADIS, a technology that supports the creation and operation of virtual knowledge bases. To this end, it provides developers with components and APIs for building secure data services that can be annotated and queried through ontology templates, based on DICOM and DICOM-SR. This technology was used in this paper to build a gateway for assisting diagnosis and research in breast cancer. We also present here the results of a study conducted to evaluate the gateway, from the point of view of the usability perceived by a group of physicians and radiologists.     

Toward a framework for evaluating ubiquitous computing applications

Although they routinely evaluate pervasive or ubiquitous computing applications, researchers have difficulty comparing results rigorously and quantitatively. The lack of a widely accepted framework for user evaluations of ubiquitous applications hampers their efforts. By proposing such a framework, we hope to help researchers compare results, create ubiquitous computing design guidelines, develop effective discount evaluation techniques, understand the appropriateness of different evaluation techniques, and develop a more complete structure so they can avoid overlooking key areas of evaluation.