Immersive Analytics is a recent field of study that focuses on utilizing emerging extended reality technologies to bring visual data analysis from the 2D screen to the real/virtual world. The effectiveness of Immersive Analytics, when compared to traditional systems, has been widely studied in this field’s corpus, usually concluding that the immersive solution is superior. However, when it comes to comparing collaborative to single-user immersive analytics, the literature is lacking in user studies. As such, we developed a comprehensive experimental study with the objective of quantifying and analysing the impact that both immersion and collaboration have on the visual data analysis process. A two-variable (immersion: desktop/virtual reality; number of users: solo/pair) full factorial study was conceived with a mixed design (within-subject for immersion and between subject for number of users). Each of the 24 solo and 24 pairs of participants solved five visual data analysis tasks in both a head-mounted display-based virtual world and a desktop computer environment. The results show that, in terms of task time to completion, there were no significant differences between desktop and virtual reality, or between the solo and pair conditions. However, it was possible to conclude that collaboration is more beneficial the more complex the task is in both desktop and virtual reality, and that for less complex tasks, collaboration can be a hindrance. System Usability Scale scores were significantly better in the virtual reality condition than the desktop one, especially when working in pairs. As for user preference, the virtual reality system was significantly more favoured both as a visual data analysis platform and a collaborative data analysis platform over the desktop system. All supplemental materials are available at https://osf.io/k94u5/.

Pedestrian simulation is often forgotten or implemented poorly in most high profile traffic simulators. This is the case of SUMO, where the pedestrian models are very simple and not based in real human behaviour, making it impossible to study pedestrian safety with it. With this in mind, the ability to externally control pedestrians in SUMO was explored. Using Unity3D to create an external three dimensional representation of a running SUMO simulation, we were able to create and control pedestrians through the TraCI API. This also opened the possibility to use virtual reality immersed subjects to participate in the simulation, opening the door to study real pedestrian behaviour to create more elaborate models. It also allowed us to completely offload the pedestrian simulation from SUMO to Unity3D, which was tested with the external implementation of the social forces model, without losing SUMO's interactions between pedestrians and motorized vehicles.

MOTIVATION: Cells are complex systems composed of hundreds of genes whose products interact to produce elaborated behaviors. To control such behaviors, cells rely on transcription factors to regulate gene expression, and gene regulatory networks (GRNs) are employed to describe and understand such behavior. However, GRNs are static models, and dynamic models are difficult to obtain due to their size, complexity, stochastic dynamics and interactions with other cell processes. RESULTS: We developed Atlas, a Python software that converts genome graphs and gene regulatory, interaction and metabolic networks into dynamic models. The software employs these biological networks to write rule-based models for the PySB framework. The underlying method is a divide-and-conquer strategy to obtain sub-models and combine them later into an ensemble model. To exemplify the utility of Atlas, we used networks of varying size and complexity of Escherichia coli and evaluated in silico modifications, such as gene knockouts and the insertion of promoters and terminators. Moreover, the methodology could be applied to the dynamic modeling of natural and synthetic networks of any bacteria. AVAILABILITY AND IMPLEMENTATION: Code, models and tutorials are available online (https://github.com/networkbiolab/atlas). SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

Wireless sensor and actuator networks (WSAN) constitute an emerging technology with multiple applications in many different fields. Due to the features of WSAN (dynamism, redundancy, fault tolerance, and self-organization), this technology can be used as a supporting technology for the monitoring of critical infrastructures (CIs). For decades, the monitoring of CIs has centered on supervisory control and data acquisition (SCADA) systems, where operators can monitor and control the behavior of the system. The reach of the SCADA system has been hampered by the lack of deployment flexibility of the sensors that feed it with monitoring data. The integration of a multihop WSAN with SCADA for CI monitoring constitutes a novel approach to extend the SCADA reach in a cost-effective way, eliminating this handicap. However, the integration of WSAN and SCADA presents some challenges which have to be addressed in order to comprehensively take advantage of the WSAN features. This paper presents a solution for this joint integration. The solution uses a gateway and a Web services approach together with a Web-based SCADA, which provides an integrated platform accessible from the Internet. A real scenario where this solution has been successfully applied to monitor an electrical power grid is presented.

Wireless sensor and actor networks (WSANs) constitute an emerging and pervasive technology that is attracting increased interest for a wide range of applications. The increasing functionality of this kind of network makes it necessary to propose tools and methodologies to facilitate software development. This paper proposes a middleware called MWSAN to provide a set of high level services for sensor and actor networks. The middleware meets the component-oriented paradigm and developers can configure it depending on the actor and sensor resources. It takes into account issues such as the network configuration, the quality of service (QoS) and the coordination among actors. MWSAN is specified in UM-RTCOM, a component model oriented to real time systems adapted to WSANs that allows us to take into account real time requirements in the applications. Additionally, we present an implementation model based on RT Java for actors. In order to apply the proposed middleware we describe an example specified in UM-RTCOM and its RT Java implementation

Wireless sensor and actor networks (WSANs) constitute a new pervasive technology. WSANs have two major requirements: coordination mechanisms for both sensor-actor and actor-actor interactions, and real-time communication to perform correct and timely actions. This paper introduces TC-WSANs, a high-level coordination model that addresses these two requirements and facilitates the application programmer task. Our proposal is based on a (hierarchical) architecture of sensor/actor clusters and the use of tuple channels to achieve communication and synchronization among sensors and actors. A tuple channel is a priority queue structure that allows data structures to be communicated both in a one-to-many and many-to-one way, facilitating the data-centric behavior of sensor queries. The characteristics of TC-WSANs and the primitives that it provides for its integration into a computational host language are presented.

Abstract This paper presents a nuclear power plant simulator kernel based on the high‐performance computing‐oriented Common Component Architecture (CCA). The approach takes advantage of both the component‐based software development and the efficient execution of parallel simulation models. The use of components improves the software life cycle and facilitates the development, maintenance and evolution of the simulator kernel, which can be adapted to different execution scenarios. Data dependencies among simulation models are resolved automatically by means of a novel algorithm, releasing the programmer from this tedious task and, as a result, making the development process easier. This work introduces the main features of the simulator kernel, describing concepts and the model on which it is based. Some preliminary results are shown that anticipate the feasibility and suitability of the proposal. Copyright © 2006 John Wiley & Sons, Ltd.

Wireless sensor and actor networks (WSANs) constitute an emerging and pervasive technology that is attracting increased interest for a wide range of applications. WSANs have two major requirements: coordination mechanisms for both sensor-actor and actor-actor interactions, and real-time communication to perform correct and timely actions. Additionally, the development of WSAN applications is notoriously difficult, due to the extreme resource limitations of nodes. This paper introduces a framework to facilitate the task of the application programmer taking into account these special characteristics of WSANs. We propose a real-time component model using light-weight components. In addition, a high-level coordination model based on tuple channels is integrated into the framework including high-level constructs that abstract the details of communication and facilitate the data-centric behavior of sensor queries.

Abstract This paper proposes the application of modern component‐oriented technologies to the development of nuclear power plant simulators. On the one hand, as a significant improvement on previous simulators, the new kernel is based on the Common Component Architecture (CCA). The use of such a high‐performance computing oriented component technology, together with a novel algorithm to automatically resolve simulation data dependencies, allows the efficient execution of both parallel and sequential simulation models. On the other hand, RT‐CORBA is employed in the development of the rest of the applications that comprise the simulator. This real‐time communication middleware not only makes the management of communications easier, but also provides the applications with real‐time capabilities. Software components used in these two ways, simulation models integrating the kernel and distributed applications from which the simulator is comprised, improve the evolution and maintenance of the entire system, as well as promoting code reusability in other projects. Copyright © 2006 John Wiley & Sons, Ltd.

The development of simulators for complex systems like nuclear power plants is a hard task where many different factors have to be considered. This paper presents a simulation environment composed by a simulation kernel and supported by a set of tools and simulation models that allow the real-time simulation of the control room of nuclear power plants. The developed simulators allow the training of the operators for the operations and maintenance of the power plant in a safe way and they are being used in full scope simulations for different real power plants. In this type of systems, where many components have to interoperate between them, the communications play a main role. The main contribution of the paper is to show the lessons learned from the utilization of CORBA and Real-time CORBA in the development of this type of simulators.

The application of new technologies and programming tools represents a challenge and an economic risk for companies, which not all are prepared to assume. We present the application of RT-CORBA in the development of software for nuclear power plant simulators used for the training of future operators in a safe way. The developed software has allowed the adaptation of previous simulation software to new methodologies and standards; and the creation of new applications, aiming at the building of reusable components with real-time constraints in future projects