Swedish Institute of Computer Science Publications Database
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Analyzing Improvements for a Mine Maintenance System of Connected Equipment and Machines - The Value and Benefits of Data Sharing
No full textA modern mine involves increasingly smart and connected products that are integrated in a mine automation system. Integration enable many possible applications that could substantially aid in achieving the goals of increased safety and productivity of the mine operation including the machine maintenance process. What data will be shared by the involved organizations and products, heavily affects how successful improvements of operation can be accommodated.
We have devised a method to map out and evaluate envisioned new collaborative functions for a complex System-of-systems such as the mine maintenance operation. The proposed method map user stories for the involved stakeholders and estimate the value of fulfillment based on different candidates of data sharing architectures. The method is explained and exemplified by a realistic example based the real case.
There seems to be a need for a method such as the presented one just to map out what new applications are really feasible. By estimating value in terms of stakeholder benefits and identifying possible showstoppers in terms of protected data, the method seems to help reveal what improvements in the mine operation is in fact possible. Deciding on a data-sharing architecture for a collaborative mine seems to provide useful design prerequisites to a developing organization improving their smart connected products
Directional Transmissions and Receptions for High-throughput Bulk Forwarding in Wireless Sensor Networks
No full textInter-network interactions in the internet-of-things: protocol and architecture challenges
No full textA Fuzzy Decision Support Approach for Model-Based Tradeoff Analysis of Non-Functional Requirements
No full textOne of the main challenges in addressing Non-Functional Requirements (NFRs) in designing systems is to take into account their interdependencies and mutual impacts. For this reason, they cannot be considered in isolation and a careful balance and tradeoff among them should be established. This makes it a difficult task to select design decisions and features that lead to the satisfaction of all different NFRs in the system, which becomes even more difficult when the complexity of a system grows. In this paper, we introduce an approach based on fuzzy logic and decision support systems that helps to identify different design alternatives that lead to higher overall satisfaction of NFRs in the system. This is achieved by constructing a model of the NFRs and then performing analysis on the model. To build the model, we use a modified version of the NFR UML profile which we have introduced in our previous works, and using model transformation techniques we automate the analysis of the model
Interference Effect on Localization Solutions: Signal Feature Perspective
No full textWe study the effect of interference on localization algorithms through the study of the interference effect on signal features that are used for localization. Particularly, the effect of interference on packet-based Received Signal Strength Indicator (RSSI), reported by IEEE 802.11 and IEEE 802.15.4 technologies, and on Time of Flight (ToF), reported by IEEE 802.15.4 technology, is studied using both theoretical discussions and experimental verifications. As for the RSSI values, using an information theoretic formulation, we distinguish three operational regimes and we show that the RSSI values, in dBm, remain unchanged in the noise-limited regime, increase almost linearly with interference power in dBm in the interference-limited regime and cannot be obtained due to packet loss in the collision regime. The maximum observable RSSI variation is dependent on the transmission rate and Signal to Noise Ratio (SNR). We also show that ToF is, interestingly, decreased under interference which is caused in the symbol synchronization procedure at the receiver. After providing the experimental results, we discuss how the localization algorithms are affected by interference
JAMMY: a Distributed and Dynamic Solution to Selective Jamming Attack in TDMA WSNs
No full textTime Division Multiple Access (TDMA) is often used in Wireless Sensor Networks (WSNs), especially for critical applications, as it provides high energy efficiency, guaranteed bandwidth, bounded and predictable latency, and absence of collisions. However, TDMA is vulnerable to selective jamming attacks. In TDMA transmission, slots are typically pre-allocated to sensor nodes, and each slot is used by the same node for a number of consecutive superframes. Hence, an adversary could thwart a victim node’s communication by simply jamming its slot(s). Such attack turns out to be effective, energy efficient, and extremely difficult to detect. In this paper, we present JAMMY, a distributed and dynamic solution to selective jamming in TDMA-based WSNs. Unlike traditional approaches, JAMMY changes the slot utilization pattern at every superframe, thus making it unpredictable to the adversary. JAMMY is decentralized, as sensor nodes determine the next slot utilization pattern in a distributed and autonomous way. Results from performance analysis of the proposed solution show that JAMMY introduces negligible overhead yet allows multiple nodes to join the network, in a limited number of superframes
