Adaptive System-Level Diagnosis in Real-Time

Author(s):  
Mark E. Stahl ◽  
Ronald P. Bianchini
Electronics ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 644
Author(s):  
Michal Frivaldsky ◽  
Jan Morgos ◽  
Michal Prazenica ◽  
Kristian Takacs

In this paper, we describe a procedure for designing an accurate simulation model using a price-wised linear approach referred to as the power semiconductor converters of a DC microgrid concept. Initially, the selection of topologies of individual power stage blocs are identified. Due to the requirements for verifying the accuracy of the simulation model, physical samples of power converters are realized with a power ratio of 1:10. The focus was on optimization of operational parameters such as real-time behavior (variable waveforms within a time domain), efficiency, and the voltage/current ripples. The approach was compared to real-time operation and efficiency performance was evaluated showing the accuracy and suitability of the presented approach. The results show the potential for developing complex smart grid simulation models, with a high level of accuracy, and thus the possibility to investigate various operational scenarios and the impact of power converter characteristics on the performance of a smart gird. Two possible operational scenarios of the proposed smart grid concept are evaluated and demonstrate that an accurate hardware-in-the-loop (HIL) system can be designed.


Author(s):  
Maniru Malami Umar ◽  
Amimu Mohammed ◽  
Abubakar Roko ◽  
Ahmed Yusuf Tambuwal ◽  
Abdulhakeem Abdulazeez

Call admission control (CAC) is one of the radio resource management techniques that regulates and provide resources for new or ongoing calls in the network. The existing CAC schemes wastes bandwidth due to its failure to check before degrading admitted real-time calls and it also increases the call dropping probability (CBP) and calling blocking probability (CBP) of real-time calls due to the delay incurred when bandwidth is degraded from them. This paper proposed an enhanced adaptive call admission control (EA-CAC) scheme with bandwidth reservation. The scheme employs a prior-check mechanism that ensured bandwidth to be degraded will be enough to admit the new call request. It further incorporates an adaptive degradation mechanism that degrades non-real time calls before degrading the RT calls. The performance of the EA-CAC scheme was evaluated against two existing schemes using Vienna LTE system level simulator. The EA-CAC scheme exhibits better performance compared to the two schemes in terms of throughput, CBP, and CDP of RT calls without sacrificing the performance of NRT calls.


Author(s):  
Scott E. Page ◽  
Jon Zelner

This chapter advocates a complex adaptive system of systems approach to understanding population-level processes in population health. A complex adaptive system consists of diverse, interacting adaptive entities whose aggregated behaviors result in emergent, system-level patterns and functionalities. A complex adaptive system of systems consists of multiple, connected complex systems. The connections can be hierarchical, horizontal, or a mixture of the two. The authors provide basic definitions, describe common tools of analysis, and introduce illustrative cases. For example, increased obesity levels have no single cause, nor do they arise from a single system. Instead, they arise from the interactions of multiple systems that operate at various levels of scale. Genetics and epigenetics play roles, as do nutrition, general health, advertising, infrastructure, social norms, exercise levels, and, as recent evidence suggests, the ecology of colonies of gut bacteria. Each of these contributors can be modeled as a complex adaptive system and the whole as a system of systems. Similarly, population-level disease outbreaks can be decomposed into separate systems, each with unique dynamics.


Fuel Cells ◽  
2019 ◽  
Vol 20 (1) ◽  
pp. 17-32 ◽  
Author(s):  
Gregor Tavčar ◽  
Tomaž Katrašnik

Electronics ◽  
2019 ◽  
Vol 8 (3) ◽  
pp. 367 ◽  
Author(s):  
Massimo Merenda ◽  
Demetrio Iero ◽  
Giovanni Pangallo ◽  
Paolo Falduto ◽  
Giovanna Adinolfi ◽  
...  

This paper presents the design and hardware implementation of open-source hardware dedicated to smart converter systems development. Smart converters are simple or interleaved converters. They are equipped with controllers that are able to online impedance match for the maximum power transfer. These conversion systems are particularly feasible for photovoltaic and all renewable energies systems working in continuous changing operating conditions. Smart converters represent promising solutions in recent energetic scenarios, in fact their application is deepening and widening. In this context, the availability of a hardware platform could represent a useful tool. The platform was conceived and released as an open hardware instrument for academy and industry to benefit from the improvements brought by the researchers’ community. The usage of a novel, open-source platform would allow many developers to design smart converters, focusing on algorithms instead of electronics, which could result in a better overall development ecosystem and rapid growth in the number of smart converter applications. The platform itself is proposed as a benchmark in the development and testing of different maximum power point tracking algorithms. The designed system is capable of accurate code implementations, allowing the testing of different current and voltage-controlled algorithms for different renewable energies systems. The circuit features a bi-directional radio frequency communication channel that enables real-time reading of measurements and parameters, and remote modification of both algorithm types and settings. The proposed system was developed and successfully tested in laboratory with a solar module simulator and with real photovoltaic generators. Experimental results indicate state-of-art performances as a converter, while enhanced smart features pave the way to system-level management, real-time diagnostics, and on-the-flight parameters change. Furthermore, the deployment feasibility allows different combinations and arrangements of several energy sources, converters (both single and multi-converters), and modulation strategies. To our knowledge, this project remains the only open-source hardware smart converter platform used for educational, research, and industrial purposes so far.


Sign in / Sign up

Export Citation Format

Share Document