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The supernumerary that erupts in the midline between two maxillary central incisors most frequently is the mesiodens. Multiple mesiodens erupting, either labial or palatal to permanent central incisors, is an uncommon disorder known as mesiodentes. It is also important to perform a thorough radiographic examination in order to avoid post operative complications. We present a unique occurrence of non-syndromic mesiodentes, or double mesiodentes. Mesiodens have effects on appearance and functionality. [ABSTRACT FROM AUTHOR]

INTRODUCTION: Mastication is coordinated motor skill that is most effective through synchronized crosstalk between the teeth, bone and muscles. A combination of molecular signaling and central pattern generators govern the development and physiology of mastication. As primates, humans have evolved with the changing dietary shifts for their survival. The adaptive mechanisms in the involved structures allows us to puncture, pierce, cut, crush, grind, nip, incise, scrap, and strip different dietary textures. OBJECTIVE: The objective of this review is to understand the developmental dynamics and rhythmogenesis of mastication in children from the point of view of myology, odontology, and evolutionary perspective. RELEVANCE: This chronological review helps in understanding how the multi-faceted nature of the masticatory apparatus comes into being from the prenatal to the prepubertal period. It enables pediatricians and pediatric dental surgeons to understand the oro-motor development while intervening with any treatment involving muscle tonicity of the masticatory organ. [ABSTRACT FROM AUTHOR]

Summary: With the increase in the penetration level of renewables into the grid, the virtual synchronous generator (VSG) concept has emerged as an attractive solution for controlling grid‐tied inverters. The variation in reactive power also affects the real power of the system as well. To address the voltage variations and phase angle variations occurring because of the energy storage elements, the control of the reactive power loop (RPL) is important. Also, it is used to maintain voltage regulation and improve the power factor of the VSG system. This paper focuses on the damping of oscillations occurring because of load variation by proper adjustment of the rotational inertia, damping coefficient, droop coefficient, and regulatory coefficient of reactive power with a proposed adaptive control strategy. Small‐signal analysis of the active and reactive power and point of common coupling (PCC) have been derived, and the detailed dynamic performances are analyzed. The influences of parameters perturbation on PCC voltage and reactive power were investigated. Furthermore, adaptive control includes optimizing dynamic indexes such as rise time, delay time, and response settling time. Finally, the performance and improvement in the results of VSG with and without adaptive control are compared. [ABSTRACT FROM AUTHOR]

Summary: This article presents an improved least mean square (LMS) algorithm‐based control approach for a three‐phase grid interfaced solar photovoltaic (GISPV) system for smart building applications. The SPV is primarily utilized to supply household loads, and the absence or intermittency of SPV is curbed by utilizing power from the grid. The majority of household loads are nonlinear loads that affect the grid power quality (PQ). However, the effects of both linear and nonlinear loads on grid PQ have been analyzed in this article. This article proposes a Gaussian Kernel function‐based normalized LMS (GKNLMS) algorithm to calculate the active peak weight component of the load current, thereby utilizing it to obtain a sinusoidal reference current. Considering a higher step size and utilizing the Gaussian Kernel function for reduced mean square error (MSE) improves both the convergence rate and accuracy of estimation in the conventional LMS. The proposed control technique effectively addresses system anomalies caused by dynamic solar irradiance, load variation, and unbalanced loading conditions. Furthermore, the system response with the GKNLMS algorithm is assessed in MATLAB/Simulink and validated by developing a laboratory setup of the system for experimentation. [ABSTRACT FROM AUTHOR]

Severe issues such as degradation of power quality and efficiency have surfaced in past few years due to extensive use of power electronic converters for conversion and control in power system. The shunt active power filter (SAPF) has gained attention as a competent solution among researchers. However, most SAPF control schemes render ineffective results under non-ideal supply conditions. A novel single-phase p–q scheme based on high selectivity filter (HSF) for extraction of reference compensation currents is proposed in this paper. A three H-bridges (3HB) voltage source inverter (VSI) topology of SAPF is considered and its dc-link voltage is regulated using an Enhanced Bacterial foraging optimization (BFO) based PI controller. This topology along with the proposed SAPF control scheme can guarantee improved APF performance as each phase of the three-phase four-wire system can be controlled independently. Extensive investigations are carried out using MATLAB/Simulink simulations followed by real-time performance verification in Opal-RT Lab. The effectiveness is assessed in terms of current harmonics, excessive neutral current and current unbalance compensation. The results obtained with proposed scheme when compared with conventional three-phase and single-phase p–q schemes employing low-pass filters (LPF) yield remarkably superior results under ideal, distorted and unbalanced supply and unbalanced loading conditions. [ABSTRACT FROM AUTHOR]

As the percentage of renewable energy source within the energy production mix has expanded, it is become gradually difficult to determine the appropriate values for controller gains and model parameters. Controlling system frequency of interconnected power system during sudden load disturbance requires careful consideration of the controller gain values and small signal stability model parameters. This study proposes an innovative methodology for ascertaining controller gain values and model parameters for plug-in electric vehicles (PEVs) in load frequency control (LFC) applications. Proposed method uses the root locus (RL) approach to find the suitable controller gain values and model parameters for PEVs. This paper offers a thorough mathematical description of the proposed RL approach. Routh approximation method is used for reduced-order modelling (ROM), which comprises thermal and PEV systems, to reduce complexity of higher-order system while designing controllers. Fractional-order proportional-integral-derivative controller (FO-PID) is proposed, and its parameters are adjusted using particle swarm optimization (PSO) tool. To validate the efficacy of suggested method, a comprehensive comparison of time response parameters and performance indices (PI) is carefully carried out. Also, the various PEVs state of charge (SOC) levels is investigated, and effects of these levels are studied in LFC with robustness analysis of controller. The proposed method for determining gain value is highly reliable and efficient, outperforming existing methodologies in the literature. [ABSTRACT FROM AUTHOR]

This article proposed an off-board bidirectional battery charger for electric vehicles (EVs) that have been designed to perform various modes of operation of EVs like grid-to-vehicle (G2V) and vehicle-to-grid (V2G) while improving the grid power quality (PQ). During the charging process, the charger operates in the G2V mode. In this mode, power flows from the utility grid to the EV, ensuring a smooth and efficient transfer, which has the ability to maintain a sinusoidal grid current waveform and a unity power factor throughout the operation. This not only ensures efficient power transfer but also minimizes disruptions and distortions in the grid. On the other side of the operational spectrum lies the discharging phase, governed by the V2G mode. This mode allows the charger to deliver power from the EV's batteries back to the utility grid. This capability is a significant step toward establishing a two-way relationship between EVs and the grid, enabling EVs to act as energy reservoirs and support grid stability during peak demand or emergencies. This paper presents the proposed adaptive direct power control (ADPC) theory for the proposed electric vehicle charger (EVC), which consists of a grid-side converter and an EV side converter. The proposed control algorithm on both sides of the converters plays a significant role in various operating modes. The ADPC employs a control strategy referred to as the second-order generalized integrator to estimate the actual synchronizing voltage templates specifically designed for single-phase grid-side converters. Consequently, the appropriate current reference used by the charger is to ensure that the power factor remains unity throughout various operating modes. Similarly, for the EV side converter, the integration of the power delivery error further enhances steady-state responses with the proposed ADPC by generating actual phase shifted pulses for the DAB. The overall performance under similar conditions is studied with virtual direct power control to further check the robustness of the proposed ADPC. The adopted topology and control technique further implemented in the prototype of an off-board EVC to verify the various operating conditions to demonstrate its effectiveness and justified as per the IEEE 519-2022 standard. [ABSTRACT FROM AUTHOR]

The power quality of the grid-coupled photovoltaic system (GCPVS) is enhanced using a control scheme developed by employing a robust generalized soft-root-sign (GSRS) adaptive filter. Power quality (PQ) deterioration issues are common in the distribution grid due to the mix of irregular loads. The GSRS control scheme mitigates harmonics, compensates load unbalances, achieves unity power factor at the grid, and compensates load reactive power, thus leading to balanced sinusoidal currents at the grid side. The GSRS algorithm utilizes a soft-root-sign cost function to achieve less steady-state misalignment while estimating magnitudes of fundamental frequency load current components for PQ improvement. The designed single-stage GCPVS performs smooth power flow between local loads and the grid without necessitating an energy storage system. The control scheme initially meets load demand and then sends any surplus power to the grid. However, if the generated PV power falls below the load demand due to environmental conditions, the additional power for the load is drawn from the grid. Moreover, voltage source converter used in the GCPVS also provides the functionality of DSTATCOM, thus avoiding the usage of additional equipment. The proposed GSRS control scheme and the GCPVS are modeled in MATLAB/Simulink. A laboratory-designed experimental setup is used to carry out the experimental validation of the GSRS control scheme and found to be performing satisfactorily. The behavior of GCPVS is verified during steady-state and dynamic conditions. The GCPVS performance is verified with the standard IEEE-519-2022, and a comparison of the GSRS algorithm with other filtering algorithms is provided. [ABSTRACT FROM AUTHOR]

This article proposed the architecture of a stand-alone photovoltaic connected system (SPVS) with energy storage. An SPVS with energy storage requires power management for various operating modes. A coordinate controller is often necessary to manage the change in control architecture depending on the operating mode. This proposed system contains a boost converter (BC) and a bidirectional switched quasi-Z-source DC-DC converter (BSQZSDC). The BC is used for two purposes. The first is extracting the maximum power from the PV. The second is to control the DC link voltage when the SPVS is not in MPPT mode; dual-loop PI controllers are used for this. The BSQZSDC is used for energy management and regulates DC link voltage when SPVS operates in MPPT mode. This paper addresses about the effective control approach that BSQZSDC used, i.e., the double-integral sliding mode control, to regulate the DC link voltage and battery current in various operating modes. Experimental results were carried out to depict that the controller reasonably achieves the control objectives and proper energy management. [ABSTRACT FROM AUTHOR]