Prevalence of Nocturnal Enuresis and Its Associated Factors in Primary School and Preschool Children of Khorramabad in 2013

Background. Nocturnal enuresis refers to an inability to control urination during sleep. This study aimed to determine the prevalence of nocturnal enuresis and its associated factors in children in the city of Khorramabad. Materials and Methods. In this descriptive-analytic, cross-sectional study, 710 male and female children were divided into two groups with equal numbers. The samples were selected from the schools of Khorramabad using the multistage cluster and stratified random sampling methods based on the diagnostic criteria of DSM-IV. The data was analyzed using the logistic regression. Results. The results showed that 8% of the children had nocturnal enuresis, including 5.2% of primary nocturnal enuresis and 2.8% of secondary nocturnal enuresis. The prevalence of nocturnal enuresis in the boys (10.7%) was higher compared with that in the girls (5.4%) (P=0.009). There were statistically significant relationships between nocturnal enuresis and history of nocturnal enuresis in siblings (P=0.023), respiratory infections (P=0.036), deep sleep (P=0.007), corporal punishment at school (P=0.036), anal itching (P=0.043), and history of seizures (P=0.043). Conclusion. This study showed that the prevalence of nocturnal enuresis in the boys was higher compared with that in the girls

X-in-the-Loop Validation of Deep Learning-Based Virtual Sensing for Lifetime Estimation of Automotive Power Electronics Converters

Health degradation issues in automotive power electronics converter systems (PECs) are present due to repetitive thermomechanical stress endured while the vehicle is in real-field operation. This stress results from heat generation, a byproduct of semiconductor operation within PECs, leading to degradation in semiconductor operating life. The best practice in academia and industry is to rely on detailed Physics-of-Failure (PoF) based models for lifetime estimation. However, the PoF-based model of PECs requires substantial computational time and robust devices to estimate lifetime accurately. According to literature surveys, the computational time of the PoF-based models could be reduced further by using a low-fidelity and/or reduced-order model (ROM) that may result in unacceptable accuracy. To fulfill this research gap, this paper proposes a real-time executable, deep learning-based virtual sensing method that enables vehicle manufacturers to estimate the lifetime of the PECs onboard. This computationally efficient virtual sensing method has been integrated into an onboard vehicle validator edge (VVE). At the same time, multiple DL configurations are being explored, and optimization is performed on compositions, hyper-parameters, training, and testing datasets to obtain the best DL model. Finally, to demonstrate the feasibility and accuracy of the proposed method before its implementation within the complex VVE, an X-in-the-Loop (XiL) test is performed with vehicle frontloading

Experimental Characterization and Electro-Thermal Modeling of Double Side Cooled SiC MOSFETs for Accurate and Rapid Power Converter Simulations

The paper presents a precise and efficient model of Double-Side Cooled (DSC) SiC MOSFET, which incorporates the dynamics of both electrical and thermal variables. It offers a suitable computational complexity for simulating transients in complex power converters. The objective is to define a model that enables multi-scale time simulations and facilitates rapid power converter design in system-level tools such as Simulink. Additionally, the model aims to achieve simulation accuracy comparable to device-level models for the next generation of SiC MOSFETs. The paper demonstrates the complete test bench measurement procedure for the device. This procedure is essential for experimentally extrapolating the intrinsic characteristics and developing a model-reduction approach based on electro-thermal modeling. The approach strikes a balance between computational complexity and level of detail. The proposed model has been seamlessly integrated into Simulink to simulate a 3-phase inverter for several grid cycles at the grid frequency. To evaluate the model’s validity, the predicted inverter performance is compared with experimental measurements. These simulations require significantly less time compared to those based on LTspice models

Extension of the Stray Voltage Capture Short-Circuit Detection Method to a 6-Phase Fault-Tolerant Dual-Motor Drive

This article investigates and validates the applicability of the recently developed stray voltage capture (SVC) ultra-fast short-circuit (SC) detection method and its extended version (ESVC) to fault-tolerant multi-motor drives. As these methods are system-based, a fault localization algorithm is also developed. Simulation analysis of the inverter stray inductances shows additional challenges for the SVC method making it hard to achieve ultra-fast SC detection. The ESVC method is slower but overcomes these challenges. The methods are adapted for a 400 V 6-phase Silicon Carbide based inverter equipped with a 2-level turn-Off hardware protection scheme. Fault under load and hard switching fault tests are performed showing the effectiveness of the ESVC in fast (smaller than 330 ns) and reliable SC detection and protection for SiC MOSFETs. The fault localization algorithm is also validated showing a localization speed smaller than 20 μs

A soft-switching inverting high step-down converter with a pair of coupled inductors and self-driven synchronous rectifier

In this paper, a non-isolated coupled-inductor high step-down converter with extended duty cycle is proposed, which operates under discontinuous conduction mode. The soft-switching condition is provided for all the switches and diodes, which results in the reduction of the switching losses, and the losses related to diode reverse recovery problem. Also, a self-drive circuit is used to automatically generate the ON and OFF gate signals of the synchronous rectifier, which recovers the gate energy and reduces the complexity. In this topology, only a single coupled inductor is proposed which decreases the size and cost of the proposed converter. A 200 W laboratory prototype is implemented, and its results confirm the validity of theoretical analysis and advantages of the proposed converter over previous structures

A Review of DC Fast Chargers with BESS for Electric Vehicles: Topology, Battery, Reliability Oriented Control and Cooling Perspectives

The global promotion of electric vehicles (EVs) through various incentives has led to a significant increase in their sales. However, the prolonged charging duration remains a significant hindrance to the widespread adoption of these vehicles and the broader electrification of transportation. While DC-fast chargers have the potential to significantly reduce charging time, they also result in high power demands on the grid, which can lead to power quality issues and congestion. One solution to this problem is the integration of a battery energy storage system (BESS) to decrease peak power demand on the grid. This paper presents a review of the state-of-the-art use of DC-fast chargers coupled with a BESS. The focus of the paper is on industrial charger architectures and topologies. Additionally, this paper presents various reliability-oriented design methods, prognostic health monitoring techniques, and low-level/system-level control methods. Special emphasis is placed on strategies that can increase the lifetime of these systems. Finally, the paper concludes by discussing various cooling methods for power electronics and stationary/EV batteries

A Review of DC Fast Chargers with BESS for Electric Vehicles: Topology, Battery, Reliability Oriented Control and Cooling Perspectives

The global promotion of electric vehicles (EVs) through various incentives has led to a significant increase in their sales. However, the prolonged charging duration remains a significant hindrance to the widespread adoption of these vehicles and the broader electrification of transportation. While DC-fast chargers have the potential to significantly reduce charging time, they also result in high power demands on the grid, which can lead to power quality issues and congestion. One solution to this problem is the integration of a battery energy storage system (BESS) to decrease peak power demand on the grid. This paper presents a review of the state-of-the-art use of DC-fast chargers coupled with a BESS. The focus of the paper is on industrial charger architectures and topologies. Additionally, this paper presents various reliability-oriented design methods, prognostic health monitoring techniques, and low-level/system-level control methods. Special emphasis is placed on strategies that can increase the lifetime of these systems. Finally, the paper concludes by discussing various cooling methods for power electronics and stationary/EV batteries