Coupled simulation of urban water networks and interconnected critical urban infrastructure systems: A systematic review and multi-sector research agenda

Adaptive planning of water infrastructure systems is crucial to bolster urban resilience in the face of climate change while meeting the needs of rapidly changing urban metabolisms. Urban water systems maintain intricate interconnections with other critical infrastructure domains (CIDs). Multi-sector dependencies and joint management of different CIDs have gained interest in recent research to mitigate undesired cascading effects across domains. Yet, combined modeling and joint simulation of multiple CIDs needs to overcome the limitations of tools and software often siloed to individual infrastructure domains. In this paper, we contribute a systematic review of 24 recent peer-reviewed publications on coupled simulation of urban water systems (water supply and drainage networks) and other CIDs, including energy grids, mobility networks, and IT infrastructure systems, extracted from a larger set of 222 publications. First, we identify trends, modeling frameworks, and simulation software enabling the combined simulation of interlinked CIDs. Then, we define an agenda of priorities for future research. Acknowledging the opportunities provided by open-source tools, data, and standardized evaluation schemes, future research fostering coupled simulation across CIDs should prioritize knowledge transfer, address differences in spatial and temporal dependencies, scale up simulations to a network level, and explore multi-sector interconnections beyond bilateral dependencies

A comparative study on energy consumption models for drones

Creating an appropriate energy consumption prediction model is becoming an important topic for drone-related research in the literature. However, a general consensus on the energy consumption model is yet to be reached at present. As a result, there are many variations that attempt to create models that range in complexity with a focus on different aspects. In this paper, we benchmark the five most popular energy consumption models for drones derived from their physical behaviours and point to the difficulties in matching with a realistic energy dataset collected from a delivery drone in flight under different testing conditions. Moreover, we propose a novel data-driven energy model using the Long Short-Term Memory (LSTM) based deep learning architecture and the accuracy is compared based on the dataset. Our experimental results have shown that the LSTM based approach can easily outperform other mathematical models for the dataset under study. Finally, sensitivity analysis has been carried out in order to interpret the model

A Comparative Study on Energy Consumption Models for Drones

Creating an appropriate energy consumption prediction model is becoming an important topic for drone-related research in the literature. However, a general consensus on the energy consumption model is yet to be reached at present. As a result, there are many variations that attempt to create models that range in complexity with a focus on different aspects. In this paper, we benchmark the five most popular energy consumption models for drones derived from their physical behaviours and point to the difficulties in matching with a realistic energy dataset collected from a delivery drone in flight under different testing conditions. Moreover, we propose a novel data-driven energy model using the Long Short-Term Memory (LSTM) based deep learning architecture and the accuracy is compared based on the dataset. Our experimental results have shown that the LSTM based approach can easily outperform other mathematical models for the dataset under study. Finally, sensitivity analysis has been carried out in order to interpret the model.Comment: Accepted at Global IoT Summit 2022 Conferenc

Control-theoretic dynamic thermal management of automotive electronics control units

There has been a large body of research on dynamic thermal management (DTM) to manage the die temperature of integrated circuits against their high power density. Control-theoreticDTMis one of the most effectiveDTMschemes that guarantee stability criteria while meeting several performance requirements such as response time, steady-state error, overshoot, undershoot, phase margin, margin, and so forth. Conventional control-theoretic DTM schemes show reasonable stability and performance for general-purpose processors, but they may not fulfill those requirements for vehicle electronics control units (ECUs) primarily because the ambient temperature of an ECU is dependent on the associated unit temperature that often exceeds 100 degrees C. This results in a high steady-state die temperature and a very narrow temperature headroom. Furthermore, the unit temperature dynamically changes according to the driving condition that acts as a major disturbance to the DTM system. This paper introduces an advanced control-theretic DTM mechanism for high-performance vehicle ECUs. We model such ambient temperature variation as a disturbance, and adopt a disturbance predictor and compensator that effectively mitigates the effects of ambient temperature variations. We demonstrate that the proposed method is superior to the previous control-theoretic DTM in terms of RMS errors, peak temperature, and thermal violation.X110sciescopu

Suspected Pulmonary Embolism during Hickman Catheterization in a Child: What Else Should Be Considered besides Pulmonary Embolism?

A 16-month-old girl with acute lymphoblastic leukemia expired during Hickman catheter insertion. She had undergone chemoport insertion of the left subclavian vein six months earlier and received five cycles of chemotherapy. Due to malfunction of the chemoport and the consideration of hematopoietic stem cell transplantation, insertion of a Hickmann catheter on the right side and removal of the malfunctioning chemoport were planned under general anesthesia. The surgery was uneventful during catheter insertion, but the patient experienced the sudden onset of pulseless electrical activity just after saline was flushed through the newly inserted catheter. Cardiopulmonary resuscitation was commenced aggressively, but the patient was refractory. Migration of a thrombus generated by the previous central catheter to the pulmonary circulation was suspected, resulting in a pulmonary embolism

A Design and Validation of 400 W PV Emulator Using Simple Equivalent Circuit for PV Power System Test

In this paper, we propose a photovoltaic emulator (PVE) composed of a series of connected power diodes with a single constant current source, rather than a power converter-based PVE. Accordingly, this enables readily verifying the operation because a the simple hardware structure and lack of a complex control algorithm. The proposed PVE can be intuitively implemented using the proposed selection criteria for the power diode and equivalent resistances. Since there is no feedback control based on complex analog/digital controls and sensors, the control response can be very fast. In addition, the proposed PVE can be easily integrated with a PV power system such as a power optimizer, to allow testing in a simple and flexible manner. Spice simulation was performed based on the electrical characteristics provided by the solar panel manufacturer, and this was utilized to validate the applied emulator circuit model, the Norton Equivalent Circuit. During the design process, the simulation helped to manufacture the PVE within error ranges satisfying the desired I–V and P–V curves, as well as the maximum power point (MPP). Partial shading could be easily implemented through use of the multiple series connection of individual PVEs, demonstrating local MPP and global MPP. A 400 W class PVE was built through appropriate power diode selection, with a thermal design to increase the output power. Moreover, its performance and feasibility were verified through intensive experiments. The measured efficiency, transient response time, and maximum transient error of the partial shading tests were 91%, 22 μs, and 5.8%, respectively

Dynamic Service Synthesis and Switching for Medical IoT and Ambient Assisted Living

In the Internet of Things (IoT), our surrounding will include a large variety of devices from different manufac- turers. One of its promising branches, the medical IoT, will also be accompanied by heterogeneous smart-home infrastructures. However, the efficacy of a medical IoT application will depend on how well the surrounding smart devices collaborate with it to serve the individual needs of the users. Pre-programmed solutions lack flexibility to adapt to each need and environment, and fail to make full use of the capabilities of a set of smart devices. In this paper, we propose a concept based on the flexible and user-friendly synthesis and switching of services for medical IoT applications. The crux of the concept is to provide a methodology in which non-experts can dynamically define services based on their needs. We describe a potential scenario, discuss the associated challenges, and present preliminary results on the feasibility of this approach. Particularly, we focus on design aspects for realizing the concept and propose the use of interpreters on the smart devices as alternative solution. We show that such an approach is feasible in terms of implementation and energy consumption while still maintaining the full flexibility of the service synthesis

A Design and Validation of 400 W PV Emulator Using Simple Equivalent Circuit for PV Power System Test

In this paper, we propose a photovoltaic emulator (PVE) composed of a series of connected power diodes with a single constant current source, rather than a power converter-based PVE. Accordingly, this enables readily verifying the operation because a the simple hardware structure and lack of a complex control algorithm. The proposed PVE can be intuitively implemented using the proposed selection criteria for the power diode and equivalent resistances. Since there is no feedback control based on complex analog/digital controls and sensors, the control response can be very fast. In addition, the proposed PVE can be easily integrated with a PV power system such as a power optimizer, to allow testing in a simple and flexible manner. Spice simulation was performed based on the electrical characteristics provided by the solar panel manufacturer, and this was utilized to validate the applied emulator circuit model, the Norton Equivalent Circuit. During the design process, the simulation helped to manufacture the PVE within error ranges satisfying the desired I–V and P–V curves, as well as the maximum power point (MPP). Partial shading could be easily implemented through use of the multiple series connection of individual PVEs, demonstrating local MPP and global MPP. A 400 W class PVE was built through appropriate power diode selection, with a thermal design to increase the output power. Moreover, its performance and feasibility were verified through intensive experiments. The measured efficiency, transient response time, and maximum transient error of the partial shading tests were 91%, 22 μs, and 5.8%, respectively