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Multi-robot systems are increasingly deployed to provide services and accomplish missions whose complexity or cost is too high for a single robot to achieve on its own. Although multi-robot systems offer increased reliability via redundancy and enable the execution of more challenging missions, engineering these systems is very complex. This complexity affects not only the architecture modelling of the robotic team but also the modelling and analysis of the collaborative intelligence enabling the team to complete its mission. Existing approaches for the development of multi-robot applications do not provide a systematic mechanism for capturing these aspects and assessing the robustness of multi-robot systems. We address this gap by introducing ATLAS, a novel model-driven approach supporting the systematic design space exploration and robustness analysis of multi-robot systems in simulation. The ATLAS domain-specific language enables modelling the architecture of the robotic team and its mission and facilitates the specification of the team's intelligence. We evaluate ATLAS and demonstrate its effectiveness in three simulated case studies: a healthcare Turtlebot-based mission and two unmanned underwater vehicle missions developed using the Gazebo/ROS and MOOS-IvP robotic platforms, respectively. [ABSTRACT FROM AUTHOR]

The integration of Multi-Processors System-on-Chip (MPSoCs) into the Internet-of-Things (IoT) context brings new opportunities, but also represent risks. Tight real-time constraints and security requirements should be considered simultaneously when designing MPSoCs. Network-on-Chip (NoCs) are specially critical when meeting these two conflicting characteristics. For instance the NoC design has a huge influence in the security of the system. A vital threat to system security are so-called side-channel attacks based on the NoC communication observations. To this end, we propose a NoC security mechanism suitable for hard real-time systems, in which schedulability is a vital design requirement. We present three contributions. First, we show the impact of the NoC routing in the security of the system. Second, we propose a packet route randomisation mechanism to increase NoC resilience against side-channel attacks. Third, using an evolutionary optimisation approach, we effectively apply route randomisation while controlling its impact on hard real-time performance guarantees. Extensive experimental evidence based on analytical and simulation models supports our findings. [ABSTRACT FROM AUTHOR]

The simulation of interconnect architectures can be a time-consuming part of the design flow of on-chip multiprocessors. Accurate simulation of state-of-the art network-on-chip interconnects can take several hours for realistic application examples, and this process must be repeated for each design iteration because the interactions between design choices can greatly affect the overall throughput and latency performance of the system. This paper presents a series of network-on-chip transaction-level model (TLM) algorithms that provide a highly abstracted view of the process of data transmission in priority preemptive and non-preemptive networks-on-chip, which permit a major reduction in simulation event count. These simulation models are tested using two realistic application case studies and with synthetic traffic. Results presented demonstrate that these lightweight TLM simulation models can produce latency figures accurate to within mere flits for the majority of flows, and more than 93% accurate link dynamic power consumption modelling, while simulating 2.5 to 3 orders of magnitude faster when compared to a cycle-accurate model of the same interconnect. [ABSTRACT FROM AUTHOR]

Wireless sensor networks (WSNs) consist of multiple, distributed nodes each with limited resources. With their strict resource constraints and application-specific characteristics, WSNs contain many challenging tradeoffs. This paper proposes a bioinspired load balancing approach, based on pheromone signalling mechanisms, to solve the tradeoff between service availability and energy consumption. We explore the performance consequences of the pheromone-based load balancing approach using (1) a system-level simulator, (2) deployment of real sensor testbeds to provide a competitive analysis of these evaluation methodologies. The effectiveness of the proposed algorithm is evaluated with different scenario parameters and the required performance evaluation techniques are investigated on case studies based on sound sensors. [ABSTRACT FROM AUTHOR]

After completing a measure of adherence to Asian cultural values, 62 East Asian American clients talked about personal issues in a counseling session with a European American counselor who either disclosed personal information or refrained from disclosing personal information. Disclosure condition and client adherence to Asian values did not predict session outcome. However, type and intimacy of disclosure were related to immediate process and session outcome. Disclosures of strategies were perceived by the clients to be more helpful than disclosures of approval/reassurance, facts/credentials, and feelings, with disclosures of insight perceived as intermediate in helpfulness. Disclosures of strategies occurred more frequently in highly rated sessions than in sessions rated low. Also, client-and counselor-perceived intimacy of disclosures was significantly correlated with client- and counselor-perceived helpfulness of disclosures, respectively. [ABSTRACT FROM AUTHOR]