Dynamic voltage scaling algorithms for soft and hard real-time system

Dynamic Voltage Scaling (DVS) has not been investigated completely for further minimizing the energy consumption of microprocessor and prolonging the operational life of real-time systems. In this dissertation, the workload prediction based DVS and the offline convex optimization based DVS for soft and hard real-time systems are investigated, respectively. The proposed algorithms of soft and hard real-time systems are implemented on a small scaled wireless sensor network (WSN) and a simulation model, respectively

Opportunistic Routing and Synchronous Transmissions Meet TSCH

Low-power wireless networking commonly uses either Time-Slotted Channel Hopping (TSCH), synchronous transmissions, or opportunistic routing. All three of these different, orthogonal approaches strive for efficient and reliable communication but follow different trajectories. With this paper, we combine these concepts into one protocol: AUTOBAHN.AUTOBAHN merges TSCH scheduling with opportunistically routed, synchronous transmissions. This opens the possibility to create long-term stable schedules overcoming local interference. We prove the stability of schedules over several days in our experimental evaluation. Moreover, AUTOBAHN outperforms the autonomous scheduler Orchestra under interference in terms of reliability by 13.9 percentage points and in terms of latency by a factor of 9 under a minor duty cycle increase of 2.1 percentage points

Solid-Set Sprinkler Irrigation Controllers Driven by Simulation Models: Opportunities and Bottlenecks

Farmers continue to show great differences in irrigation water use, even for a given location and crop. Irrigation advisory services have narrowed the gap between scientific knowledge and on-farm scheduling, but their success has been limited. The performance of sprinkler irrigation is greatly affected by factors such as wind speed, whose short-time variability requires tactical adjustments of the irrigation schedule. Mounting energy costs often require the consideration of interday and intraday tariff evolution. Opportunities have arisen that allow these challenges to be addressed through irrigation controllers guided by irrigation and crop simulation models. Remote control systems are often installed in collective pressurized irrigation networks. Agrometeorological information networks are available in regions worldwide. Water users’ associations use specialized databases for water management. Different configurations of irrigation controllers based on simulation models can develop, continuously update, and execute irrigation schedules aiming at maximizing irrigation adequacy and water productivity. Bottlenecks requiring action in the fields of research, development, and innovation are analyzed, with the goal of establishing agendas leading to the implementation and commercial deployment of advanced controllers for solid-set irrigation.Peer ReviewedSprinkler irrigationControlModelsIrrigation systemsIrrigation districtsPublishe

A Survey of Techniques For Improving Energy Efficiency in Embedded Computing Systems

Recent technological advances have greatly improved the performance and features of embedded systems. With the number of just mobile devices now reaching nearly equal to the population of earth, embedded systems have truly become ubiquitous. These trends, however, have also made the task of managing their power consumption extremely challenging. In recent years, several techniques have been proposed to address this issue. In this paper, we survey the techniques for managing power consumption of embedded systems. We discuss the need of power management and provide a classification of the techniques on several important parameters to highlight their similarities and differences. This paper is intended to help the researchers and application-developers in gaining insights into the working of power management techniques and designing even more efficient high-performance embedded systems of tomorrow