829 research outputs found

    XRound : A reversible template language and its application in model-based security analysis

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    Successful analysis of the models used in Model-Driven Development requires the ability to synthesise the results of analysis and automatically integrate these results with the models themselves. This paper presents a reversible template language called XRound which supports round-trip transformations between models and the logic used to encode system properties. A template processor that supports the language is described, and the use of the template language is illustrated by its application in an analysis workbench, designed to support analysis of security properties of UML and MOF-based models. As a result of using reversible templates, it is possible to seamlessly and automatically integrate the results of a security analysis with a model. (C) 2008 Elsevier B.V. All rights reserved

    Semantic multimedia remote display for mobile thin clients

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    Current remote display technologies for mobile thin clients convert practically all types of graphical content into sequences of images rendered by the client. Consequently, important information concerning the content semantics is lost. The present paper goes beyond this bottleneck by developing a semantic multimedia remote display. The principle consists of representing the graphical content as a real-time interactive multimedia scene graph. The underlying architecture features novel components for scene-graph creation and management, as well as for user interactivity handling. The experimental setup considers the Linux X windows system and BiFS/LASeR multimedia scene technologies on the server and client sides, respectively. The implemented solution was benchmarked against currently deployed solutions (VNC and Microsoft-RDP), by considering text editing and WWW browsing applications. The quantitative assessments demonstrate: (1) visual quality expressed by seven objective metrics, e.g., PSNR values between 30 and 42 dB or SSIM values larger than 0.9999; (2) downlink bandwidth gain factors ranging from 2 to 60; (3) real-time user event management expressed by network round-trip time reduction by factors of 4-6 and by uplink bandwidth gain factors from 3 to 10; (4) feasible CPU activity, larger than in the RDP case but reduced by a factor of 1.5 with respect to the VNC-HEXTILE

    Point clouds by SLAM-based mobile mapping systems: accuracy and geometric content validation in multisensor survey and stand-alone acquisition

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    The paper provides some operative replies to evaluate the effectiveness and the critical issues of the simultaneous localisation and mapping (SLAM)-based mobile mapping system (MMS) called ZEB by GeoSLAM™ https://geoslam.com/technology/. In these last years, this type of handheld 3D mapping technology has increasingly developed the framework of portable solutions for close-range mapping systems that have mainly been devoted to mapping the indoor building spaces of enclosed or underground environments, such as forestry applications and tunnels or mines. The research introduces a set of test datasets related to the documentation of landscape contexts or the 3D modelling of architectural complexes. These datasets are used to validate the accuracy and informative content richness about ZEB point clouds in stand-alone solutions and in cases of combined applications of this technology with multisensor survey approaches. In detail, the proposed validation method follows the fulfilment of the endorsed approach by use of root mean square error (RMSE) evaluation and deviation analysis assessment of point clouds between SLAM-based data and 3D point cloud surfaces computed by more precise measurement methods to evaluate the accuracy of the proposed approach. Furthermore, this study specifies the suitable scale for possible handlings about these peculiar point clouds and uses the profile extraction method in addition to feature analyses such as corner and plane deviation analysis of architectural elements. Finally, because of the experiences reported in the literature and performed in this work, a possible reversal is suggested. If in the 2000s, most studies focused on intelligently reducing the light detection and ranging (LiDAR) point clouds where they presented redundant and not useful information, contrariwise, in this sense, the use of MMS methods is proposed to be firstly considered and then to increase the information only wherever needed with more accurate high-scale methods

    AUTOMATED IFC-BASED PROCESSES IN THE CONSTRUCTION SECTOR: A METHOD FOR IMPROVING THE INFORMATION FLOW

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    One of the main challenges in the implementation of BIM-based processes concerns interoperability issues. In fact, even if IFC format is recognised as an ISO standard, different barriers and problems are often encountered in IFC adoption. Generally, obstacles are due to the difficulty of users in personalising import and export options of IFC formats in BIM authoring tools with the consequent possibility of information loss. The paper presents a method for improving the information flow, based on the connection of information stored in IFC files and in external databases through automated processes. Therefore, information concerning one single project can be stored in BIModels and linked to external sources or, conversely, referred from external databases to objects in BIModels. Benefits deriving from the adoption of the proposed solutions concern the limited size of BIModels, the possibility to store information not considered in the IFC schema, and the reduction of IT skills required to building operators for exchanging information in an interoperable way

    Enabling collaboration in virtual reality navigators

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    In this paper we characterize a feature superset for Collaborative Virtual Reality Environments (CVRE), and derive a component framework to transform stand-alone VR navigators into full-fledged multithreaded collaborative environments. The contributions of our approach rely on a cost-effective and extensible technique for loading software components into separate POSIX threads for rendering, user interaction and network communications, and adding a top layer for managing session collaboration. The framework recasts a VR navigator under a distributed peer-to-peer topology for scene and object sharing, using callback hooks for broadcasting remote events and multicamera perspective sharing with avatar interaction. We validate the framework by applying it to our own ALICE VR Navigator. Experimental results show that our approach has good performance in the collaborative inspection of complex models.Postprint (published version

    Change Impact Analysis based on Formalization of Trace Relations for Requirements

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    Evolving customer needs is one of the driving factors in software development. There is a need to analyze the impact of requirement changes in order to determine possible conflicts and design alternatives influenced by these changes. The analysis of the impact of requirement changes on related requirements can be based on requirements traceability. In this paper, we propose a requirements metamodel with well defined types of requirements relations. This metamodel represents the common concepts extracted from some prevalent requirements engineering approaches. The requirements relations in the metamodel are used to trace related requirements for change impact analysis. We formalize the relations. Based on this formalization, we define change impact rules for requirements. As a case study, we apply these rules to changes in the requirements specification for Course Management System

    Microservices: Granularity vs. Performance

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    Microservice Architectures (MA) have the potential to increase the agility of software development. In an era where businesses require software applications to evolve to support software emerging requirements, particularly for Internet of Things (IoT) applications, we examine the issue of microservice granularity and explore its effect upon application latency. Two approaches to microservice deployment are simulated; the first with microservices in a single container, and the second with microservices partitioned across separate containers. We observed a neglibible increase in service latency for the multiple container deployment over a single container.Comment: 6 pages, conferenc

    EMBRACING CONCEPTUAL MODELLING TO ENABLE THE MEDIATION ROLE OF ENTERPRISE INFORMATION SYSTEMS

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    Nowadays, digital environments are getting a more important role than ever in shaping the way in which enterprise operations are conducted and enterprises are being developed. Traditional information systems (IS) used by enterprises need to evolve in order to accommodate the shift of their role from representation to mediation, role that has been recently conceptualized but not sufficiently researched to identify means that enable its operationalization across domains and purposes. This work identifies what are the key enablers and how should these be applied regardless of the domain of interest. For this, our paper showcases the development of a new enterprise system that serves as a proof-of concept artifact that operationalizes the before mentioned new role of the IS. Our proposal relies on Conceptual Modelling together with all the other related enablers like Digital Twins, metamodeling platforms or model-driven operation. In this way, we want to highlight the benefits of Conceptual Modelling in providing a new abstractization layer between the digital and the physical worlds, supporting roundtrip engineering capabilities. Our example concerns the modern organization that continuously aims to become more innovative and gain competitive advantage therefore, it employs smart devices like drones in different business operations
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