bluuebunny/crossref_metadata_2025_split huggingface dataset:
Single-bit modulator for wireless power transfer system
Authors: Almakhles Dhafer , Swain Akshya , Subramaniam Umashankar 
Published: December 2019

<p>This paper proposes a single-bit ADC system based Proportional and Integral (PI) controller to maintain a desired level of power transfer efficiency in Capacitive Power Transfer (CPT) systems. In this paper, a simple single-bit ADC system i.e., Single-Bit Modulator (SBM) is considered as an alternative to the commonly used multi-bit ADC systems. Unique features of employing SBM are 1) its ability to convert analog signals into single-bit signals and 2) its easy integrability in digital chips with linear variable differential transformers (LVDTs) such as FPGAs. A SBM based PI (SBM-PI) controller is designed to judicially interface with the single-bit output of SBM. The proposed (SBM-PI) controller guarantees less hardware resources, latency and regulates the output voltage to provide the desired power transfer efficiency. The behavior of SBM-PI controller is compared to that of a conventional multi-bit controller, with the results of both controllers being identical. The effectiveness of the proposed controller with SBM is further demonstrated using the experimental prototype of CPT by implementing a SBM-PI controller using $16$ MHz ATmega8 microcontroller. The experimental results from a laboratory prototype illustrate that SBM-PI controller successfully regulates the output voltage of CPT to control the power flow.</p>
High performance PV system based on artificial neural network MPPT with PI controller for direct current water pump applications
Authors: Attia Hussain 
Published: December 2019

<span lang="EN-US">This paper presents a new design of a standalone photovoltaic system which is supplying the required power to a direct current water pump that have difficulty to supply by the utility electricity. The system is controlled by an artificial neural networks (ANN) algorithm with function softening by PI controller that to guarantee the maximum power point tracking (MPPT) working conditions. A parallel connected PV array is designed to supply the required power to the water pump. The proposed design considers Permanent Magnet DC motor (PMDC) of 48 Volts, and 500 Watts as a water pump’s motor, the direct current (DC) pump is adopted to avoid the complexity of the alternating current AC pumping system which includes inverter, power filter, and insulated step up transformer, so the presented design avoids the mentioned AC system components. A feed forward ANN algorithm is adopted in this study to produce the reference voltage for the MPPT functioning of the PV system, Proportional Integral (PI) controller is inserted to soften the MPPT controller performance. System design, MATLAB simulation with results and the results’ analysis all are presented in this paper. The study conclusion confirms the effectiveness of the proposal as a successful system for practical applications. </span>
Bridgeless PFC single ended primary inductance converter in continuous current mode
Authors: Rai Nor Akmal , Aziz Mohd Junaidi Abdul , Sahid Mohd Rodhi , Ayob Shahrin Md. 
Published: December 2019

This paper presents bridgeless single ended primary inductor (SEPIC) converter operated in continuous conduction mode (CCM). The converter used in the study offers a lesser conduction loss compared to the other bridgeless SEPIC converter. In order to regulate the required output current and output voltage with high efficiency while achieving high power factor correction (PFC) at the input side, average current mode control (ACMC) is applied. The model is simulated using MATLAB/Simulink and it is found that the converter and the proposed control strategy provide a promising result. The preliminary results obtained from the experimental test-rig shows a good agreement as in simulation. The theoretical analysis of the proposed controller is verified on an output 100V to 300W prototype.
Enhanced decoupled current control with voltage compensation for modular multilevel converter (MMC) based STATCOM
Authors: Lawan Abdurrahman Umar , Almurib Haider A.F. , Khor Jeen G. 
Published: December 2019

<p>This paper presents the application of modular multilevel converter (MMC) as a static compensator (STATCOM) for reactive current control. The current control is mostly achieved using proportional controller, proportional-integral (PI) controller, and hysteresis controller among others. PI controllers have the advantage of low harmonics and small variations. However, due to the PI controller’s dependency on the system parameters and also due to the variations within the MMC during capacitors voltage control, variation in the MMC performance during the STATCOM non-ideal operations occur. To mitigate this, an improved performance of MMC will be presented using vector-based compensation concept. The proposed control will be introduced to depress the effect of the dynamics of the MMC based STATCOM non-ideal variations considering the impact of the voltage disturbance. This will be achieved by the introduction of voltage variables to subtract the transient variations from PI controllers’ outputs at the grid-interface; thus, improving the performance.</p>
Speed performance evaluation of BLDC motor based on dynamic wavelet neural network and PSO algorithm
Authors: Obed Adel Ahmed , Saleh Ameer Lateef , Kadhim Abbas Kareem 
Published: December 2019

<span>In this paper, several methods are developed to control the brushless DC (BLDC) motor speed. Since it is difficult to get a good showing by utilizing classical PID controller, the Dynamic Wavelet Neural Network (DWNN) is the proposed work in this paper, with parallel PID controller to obtain an novel controller named DWNN-PID controller. It collects the artificial neural ability of its networks for imparting from motor of BLDC with drive system and the ability of identification for the wavelet decomposition and control of the dynamic system furthermore to have ability for adapting and self-learning. The suggested controller method is utilizing to control the speed of BLDC motor of which supply a better showing than utilizing classical controllers with a wide range of control. The proposed controller parameters are matched continuously using Particle Swarm Optimization (PSO) algorithm. The simulation results based on proposed DWNN-PID controller demonstrate a superior in the stability and performance compared at utilizing classical WNN-PID and conventional PID controllers. The simulation results are accomplished using Matlab/Simulink. It shows that the proposed control scheme has a superior performance.</span>
Design and optimization of HTS flux-switching permanent magnet machine
Authors: Shuraiji Ahlam Luaibi , Al-ani M.M.J. 
Published: December 2019

<p>Flux-switching permanent magnet (FSPM) machine with high temperature superconductors (HTS) bulks located between the rotor poles to eliminate the flux leakage in the rotor, termed as (HTS-FSPM) machine has been proposed in this paper. Using genetic algorithm, the HTS and the conventional FSPM machines having the same size constraints and load conditions have been globally optimized for max. aveage torque. To highlight the advantages of the HTS-FSPM machine, a performance comparison between the conventional and HTS-FSPM machines has been presented. It is found that the HTS-FSPM machine can increase the torque by 27%, however, this comes with the expense of higher torque ripple and power losses. </p>
A smart cascaded H-bridge multilevel inverter with an optimized modulation techniques increasing the quality and reducing harmonics
Authors: Babkrani Youssef , Naddami Ahmed , Hilal Mohamed 
Published: December 2019

<span>The world community relied heavily on fossils energies but just after the big oil crisis the use of renewable energy has greatly increased and has become the main interest of many countries for its many advantages such as: minimal impact on the environment, renewable generators requiring less maintenance than traditional ones and it has also a great impact on economy. It is easy to get charmed by the advantages of using the renewable resources but we must also be aware of their disadvantages. One of the major disadvantages is that the renewable energy resources are intermittent and thus they have led scientists to develop new semiconductor power converters among which are the multilevel inverter. In this paper a new smart multi-level inverter is proposed so as to increase its levels according to the user’s needs and also to avoid the impact of shades and the intermittence on photovoltaic panels. We also propose a modification on the multicarrier aiming to reduce the harmonics. This modification introduces a sinusoidal wave compared with trapezoidal multi-carrier to generate the pulses. In order to obtain the line voltages and the total harmonic distortions (THD) MATLAB/SIMULINK is used.</span>
Robust power control methods for wind turbines using DFIG-generator
Authors: El Karaoui Imane , Maaroufi Mohammed , Bossoufi Badre 
Published: December 2019

<span>The purpose of this work is to present the advantages of the power control (active and reactive) of a wind energy system in order to improve the quality of the energy produced to the grid by presenting two control strategies applied to the conversion system of wind energy equipped with an asynchronous generator with dual power supply. Both techniques are studied and developed and consist of a field control (FOC) and a sliding mode control. They find their strongest justifications for the problem of using a nonlinear control law that is robust to the uncertainties of the model. The goal is to apply these two commands to independently control the active and reactive powers generated by the decoupled asynchronous machine by flow orientation. Thus, a study of these commands will be detailed and validated in the Matlab / Simulink environment with the simultaneous use of the "Pitch Control" and "Maximum Power Point Tracking (MPPT)" techniques. The results of numerical simulations obtained show the increasing interest of the two controls in the electrical systems. They also attest that the quality of the active and reactive powers and voltages of the wind system is considerably improved.</span>
Design and Analysis of In-Wheel Double Stator Slotted Rotor BLDC Motor for Electric Bicycle Application
Authors: Farina S. , Firdaus R.N. , Azhar F. , Azri M. , Ahmad M. S. , Suhairi R. , Jidin A. , Sutikno Tole 
Published: December 2019

<p>This paper discusses about design and analysis of double stator slotted rotor (DSSR) BLDC motor for electric bicycle application. Usually single stator (SS) BLDC motor is used in an electric bicycle. This type of motor has low performance and need to be charged regularly. The objective of this research is to design and analysis DSSR motor that have high torque. At starts, design specification for the electric bicycle is calculated. Next, design process for DSSR is carried out by using the desired parameter. Lastly, analysis for double stator slotted rotor is simulated using FEM. Result for average back emf, average inductance, inner stator flux density, outer stator flux density, average torque and estimate torque constant is obtained. Result for average torque from FEM archieve the requirement of motor torque for DSSR design where the maximum average torque is 16.2 Nm. This research will give benefit to mankind and society in term of environment protection and energy consumption.</p>
A Novel Line Current Control Strategy to Control the Real Power Flow at PCC using H-bridge Inverter
Authors: Salem Qusay , Xie Jian 
Published: December 2019

<p class="abstract">This paper presents the power flow control between the main grid and the microgrid in low-voltage distribution network using H-bridge inverter. Controlling the real power flow in the line using the H-bridge inverter is investigated by implementing the line current control strategy. The feasibility of the proposed H-bridge inverter and its control strategy is validated by varying the line current reference. Hence, the H-bridge inverter will operate in its inductive or capacitive operation mode depending on the reference current value and the output of the PI controller in the control unit. The control strategy of the microgrid distributed generators has also been investigated in which P/V droop characteristics is applied to the power control of each DG in the microgrid. The effectiveness of the proposed approaches is validated through simulations. </p>
Predictive Approach for Power Quality Improvement Based Direct Power Control
Authors: Medouce Houssam Eddine , Benalla Hocine 
Published: December 2019

The extensive use of non-linear loads in industry becomes increasingly a serious problem that affects the quality of energy delivered to customers. Therefore, the shunt active power filter (SAPF) has emerged as an important industrial tool to eliminate induced harmonic currents and compensating of reactive power. This paper proposes an improved control configuration for SAPF based on a modern technique called predictive direct power control (Predictive-DPC). The principle of this control is based on the direct regulation of the instantaneous active and reactive powers to guarantee a good energy quality on the grid side. For this purpose the appropriate average voltage vector which cancels power tracking errors is calculated by a simple predictive model at the bigining of each control period. This type of control includes various features such as the lack of look up table (LUTs) and closed current loops and the constant switching frequency is achieved through the use of PWM modulation. The results of the simulation process show a high performance in the steady and transient state function for predictive-DPC control that might be a reasonable alternative to conventional DPC in the field of active power filtering.
Implementation of NN controlled DVR for Enhancing The Power Quality By Mitigating Harmonics
Authors: Periaswamy Abirami , Lizbeth George Merin 
Published: December 2019

<p>Now a days there is a widespread use of semiconductor devices, which are mostly implemented as the power switches for converters and inverters. These converters and inverters play a vital role in power systems both in transmission and distribution systems. This provides a way for the introduction of harmonics in the power system which leads to poor power quality. To overcome this many solutions have been suggested by the research community but each solution holds its own merits and demerits. Of all these suggested solutions, the Dynamic Voltage Restorer is one of the most cost effective systems for various power quality issues. In this paper the DVR is considered for enhancing the power quality by reducing the harmonics generated because of sensitive loads. Here the power quality is enhanced by controlling the DVR using Neural Network Controller which is trained by Levenberg Marquardt algorithm. In this paper the THD analysis of the voltage quantity is analysed by introducing an unbalanced three phase fault in the system. The simulation is done by using MATLAB/Simulink. From the results, it is verified that the harmonics are reduced by the NN controlled DVR unit. Also the simulation results are verified with the hardware results. </p>
MPPT Control for Wind Energy Conversion System Based on a T-S Fuzzy
Authors: Benkada Abdennasser , Chaikhy H. , Monkade M. 
Published: December 2019

<span lang="EN-US">In this paper, we focus on the modeling and control of a wind power system based on a Permanent Magnet Synchronous Generator (PMSG). We proposed a technique of control strategies to have the maximum power from wind turbine (WT). This study deals with the problem of Maximum Power Point Tracking (MPPT) based on Takagi Sugeno fuzzy model. The stability analysis is achieved. The gains of the designed controller are calculated by solving Linear Matrix Inequality (LMI). Finally, simulation results are provided to demonstrate the validity and the effectiveness of the proposed method. </span>
Transformation and Upwelling of Bottom Water in Fracture Zone Valleys
Authors: Thurnherr A. M. , Clément L. , St. Laurent L. , Ferrari R. , Ijichi T. 
Published: December 2019

AbstractClosing the overturning circulation of bottom water requires abyssal transformation to lighter densities and upwelling. Where and how buoyancy is gained and water is transported upward remain topics of debate, not least because the available observations generally show downward-increasing turbulence levels in the abyss, apparently implying mean vertical turbulent buoyancy-flux divergence (densification). Here, we synthesize available observations indicating that bottom water is made less dense and upwelled in fracture zone valleys on the flanks of slow-spreading midocean ridges, which cover more than one-half of the seafloor area in some regions. The fracture zones are filled almost completely with water flowing up-valley and gaining buoyancy. Locally, valley water is transformed to lighter densities both in thin boundary layers that are in contact with the seafloor, where the buoyancy flux must vanish to match the no-flux boundary condition, and in thicker layers associated with downward-decreasing turbulence levels below interior maxima associated with hydraulic overflows and critical-layer interactions. Integrated across the valley, the turbulent buoyancy fluxes show maxima near the sidewall crests, consistent with net convergence below, with little sensitivity of this pattern to the vertical structure of the turbulence profiles, which implies that buoyancy flux convergence in the layers with downward-decreasing turbulence levels dominates over the divergence elsewhere, accounting for the net transformation to lighter densities in fracture zone valleys. We conclude that fracture zone topography likely exerts a controlling influence on the transformation and upwelling of bottom water in many areas of the global ocean.
Effect of rational-emotive adult education intervention on burnout symptoms among primary school teachers in Southeast Nigeria
Authors: Nwabuko Linus Okechukwu , Eze Georgina Chinagorom , Eneh Eberechukwu Charity , Okechukwu Ann Ebere , Udom Inwang Etim 
Published: December 2019

Objective To determine the effect of a rational-emotive adult education intervention (REAEI) on burnout symptoms among primary school teachers in Southeast Nigeria. Methods Primary school teachers with burnout symptoms were randomised to treatment or control condition. Treatment was a 16-week REAEI programme delivered in 32 group therapeutic sessions. The Teachers’ Burnout Inventory (TBI) score was recorded before and after therapy and at a three-month follow-up. Results Overall, 27% (86/320) of the sample of primary school teachers had burnout symptoms. TBI scores were statistically significantly lower in the treatment group compared with the control group both after therapy and at the three- month follow up. Conclusion In this sample of primary school teachers, burnout symptoms were alleviated by use of a REAEI program.
Trends in chronic hepatitis B treatment-related research from 1973 to 2018: a bibliometric and visual analysis
Authors: Li Guiyu , Lin Jiyong , Jiang Cen , Feng Quansheng , Wen Li 
Published: December 2019

Objective Chronic hepatitis B (CHB) is a worldwide disease and the most common cause of liver cancer. This study aimed to identify specific areas of research activity concerning CHB treatment between 1973 and 2018 and to aid in identifying new areas for future development. Methods The literature was searched from the GoPubMed and Web of Science databases using terms related to CHB treatment, analyzed with bibliometric methods and visualized using VOSviewer. Results A total of 9486 and 5883 papers were collected from PubMed and Web of science, respectively. The studies focused on two clusters of topics: antiviral therapy for CHB and progressive diseases, and drug resistance. Studies related to antiviral drugs concentrated on lamivudine (n = 788), entecavir (n = 390), and adefovir dipivoxil (n = 376). Studies addressing conditions developing from CHB highlighted hepatocellular carcinoma (n = 403) and cirrhosis (n = 223). China (n = 1978) contributed the most publications. The 10 most quantitatively prolific organizations were in France. All 20 of the most cited papers investigated antiviral treatments for CHB or CHB-associated cirrhosis. Conclusions Research on CHB treatment over the past 45 years has concentrated on antiviral therapy, CHB-associated progressive conditions, drug resistance and immunization. Although work on CHB treatment has made considerable progress, new approaches must be explored.
Application of bedside real-time tracheal ultrasonography for confirmation of emergency endotracheal intubation in patients in the intensive care unit
Authors: Chen Weiting , Chen Junbo , Wang Hehao , Chen Yingzi 
Published: December 2019

Objective Critically ill patients often require emergency endotracheal intubation and mechanical ventilation. When esophageal intubation is not confirmed early, treatment may be delayed, even for life-threatening conditions. We examined the accuracy of bedside real-time airway ultrasonography in confirming the endotracheal tube (ETT) position during emergency endotracheal intubation in patients in the intensive care unit (ICU). Methods This single-center prospective observational study included 118 patients who underwent urgent endotracheal intubation in the ICU of Taizhou Hospital of Integrated Traditional Chinese and Western Medicine. Tracheal ultrasonography was used to confirm the ETT position during endotracheal intubation, after which fiberoptic bronchoscopy was performed. The accuracy of bedside real-time tracheal ultrasonography in determining the ETT position was examined. Results Twelve (10.2%) patients underwent endotracheal intubation. The kappa value was 0.844, indicating perfect consistency between tracheal ultrasonography and fiberoptic bronchoscopy in identifying esophageal intubation. The sensitivity, specificity, and positive and negative predictive values of tracheal ultrasonography in determining the ETT position were 75.0%, 100%, 100%, and 97.2%, respectively. Conclusions Bedside real-time tracheal ultrasonography accurately assesses the ETT position in the ICU and can identify the ETT position during intubation. These findings have important clinical applications and are of great significance for treatment of ICU patients.
Outcomes of coronary rotational atherectomy in patients with reduced left ventricular ejection fraction
Authors: Zhang Hui-Ping , Zhao Ying , Ai Hu , Li Hui , Tang Guo-Dong , Zheng Nai-Xin , Sun Fu-Cheng 
Published: December 2019

Objective We evaluated the safety and efficacy of rotational atherectomy (RA) in patients with a reduced left ventricular ejection fraction (LVEF). Methods In total, 140 consecutive patients with severe coronary artery calcification (CAC) who underwent RA were retrospectively enrolled. Patients were grouped based on LVEF: ≤35% (n = 10), 36% to 50% (n = 11), and >50% (n = 119). We assessed procedural success and periprocedural complication rates as well as the incidences of in-hospital and 2-year major adverse cardiac events (MACEs), defined as hospitalization for myocardial infarction and worsening heart failure, target vessel revascularization, and cardiac death. Results Procedural success was achieved in nearly all patients in each group. Most periprocedural complications were minor, and major complications were uncommon. The 2-year MACE rate was significantly higher in the LVEF ≤35% than LVEF >50% group (40.0% vs. 6.7%, respectively). Multivariable regression analysis revealed that the LVEF was the only independent predictor of 2-year MACEs in patients who underwent RA. Conclusions Patients with a reduced LVEF who underwent RA had procedural success rates similar to those of patients with preserved left ventricular systolic function. The LVEF might be an independent predictor of 2-year MACEs in patients with severe CAC after percutaneous coronary intervention following RA.