Abstract
This study presents a four-element compact Multi-Input Multi-Output antenna with enhanced isolation for applications with three bands. The four-port antenna elements have hook-shape multiband monopole elements with 50 ⦠microstrip feed lines and are placed such that they are perpendicular ...
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This study presents a four-element compact Multi-Input Multi-Output antenna with enhanced isolation for applications with three bands. The four-port antenna elements have hook-shape multiband monopole elements with 50 ⦠microstrip feed lines and are placed such that they are perpendicular to one another to enhance the act of the MIMO system. Simulation and measurement consequences demonstrate that the antenna operates at a consistent gain and radiation patterns at the major frequency bands of 2.11-2.47 GHz, 3.14-3.54 GHz, and 5.15-5.85 GHz with S11<-10 dB. To verify the claimed MIMO antenna performance, data in the format of radiation patterns, peak gain (4.9,5.2,5.8 dB), diversity gain (DG) (9.95,9.92,9.92 dB), envelope correlation coefficient (ECC) (0.005,0.003,0.002), TRAC, channel capacity and MEG ratio are retrieved. These specifications of the suggested antenna make it a suitable candidate for WiMAX, Bluetooth, and WLAN uses. Additionally, the suggested antenna outperformed current work by providing a superior balance of size, bandwidth, and several performance characteristics.
Abstract
Distribution systems pose a significant challenge within the power grid, primarily due to their high current, low voltage, and comparatively high ohmic resistance compared to transmission and sub-transmission systems.This results in substantial power losses, necessitating the need for effective mitigation ...
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Distribution systems pose a significant challenge within the power grid, primarily due to their high current, low voltage, and comparatively high ohmic resistance compared to transmission and sub-transmission systems.This results in substantial power losses, necessitating the need for effective mitigation strategies.To address this issue, a wide range of methods and algorithms have been proposed and continuously developed. Over the past half-century, reconfiguring the distribution network has emerged as a cost-effective and straightforward approach to reducing distribution losses. Distribution system reconfiguration has been extensively studied, with each study aiming to achieve distinct objectives. Additionally, numerous studies have explored the dynamics of distribution system reconfiguration, evaluating and comparing various approaches. This study comprehensively assesses both static and dynamic methods of reconfiguring distribution systems and introduces a novel dynamic reconfiguration technique. Unlike traditional methods that rely on real-time or hourly load models, this approach utilizes a load model to address the dynamic reconfiguration problem. Simulations were conducted on the well-established IEEE 33-bus test system, employing MATLAB software in conjunction with a genetic algorithm to minimize losses and optimize voltage profiles. Based on the simulation results, this novel dynamic reconfiguration method demonstrated superior performance compared to previously employed methods. It effectively reduced power losses and enhanced the voltage profile, demonstrating its potential for improving the overall efficiency of distribution systems.
Abstract
As an emerging technology, reversible computing enables the development of high-performance computing systems with low energy consumption. A residue number system (RNS) that performs arithmetic operations in parallel with error tolerance and no carry propagation requires forward and reverse converters ...
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As an emerging technology, reversible computing enables the development of high-performance computing systems with low energy consumption. A residue number system (RNS) that performs arithmetic operations in parallel with error tolerance and no carry propagation requires forward and reverse converters to communicate with other digital circuits. Designing reversible forward and reverse converters using new technologies is very important due to their wide applications in implementing the RNS. These converters, which are the overhead of the system, increase energy consumption. This study proposes a hybrid converter conforming to reversible logic for the RNS. This hybrid converter unifies forward and reverse converters by sharing hardware and reversible gates. By using the mixed-radix conversion (MRC), the reverse conversion arithmetic relations adopt a similar format to that of the forward conversion arithmetic relations, and by the addition of a number of Fredkin gates and modifying the inputs, the reverse converter hardware is used to perform forward conversion. Based on the findings, the hybrid converter, which conformed to reversible logic for the moduli set {2^2n,2^n-1,2^(n+1)-1} and {2^n-1,2^n+1,2^2n+1}, decreased the quantum cost to 19.56% and 19.52%, respectively.
Abstract
This paper presents the construction of a method to find the optimal route for ships with two criteria: fuel consumption and sailing time. Unlike most previous studies, the data used in this research was generated from a simulation model using the HIL (Hardward-In-The-Loop) technology instead of real ...
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This paper presents the construction of a method to find the optimal route for ships with two criteria: fuel consumption and sailing time. Unlike most previous studies, the data used in this research was generated from a simulation model using the HIL (Hardward-In-The-Loop) technology instead of real operational data. The HIL simulator is built from equations of the ship's 6 degrees of freedom (6-DOF), models of environmental disturbances, propulsion systems, and technical records of the real ship. In fact, operating data of the real ship is collected from noon reports, which are often incomplete in terms of environmental disturbances acting on the ship, not to mention the large sampling time (usually updated once a day). Meanwhile, the dataset generated from the HIL simulator will fully include the three main environmental components acting on ships, including waves, wind, and currents, with various scenarios. Based on that dataset, an algorithm to find optimal routes with two criteria is proposed using neural networks and the A-star algorithm. Test results show that the proposed algorithm operates reliably and has low errors. This research can be applied to find the optimal routes for small and medium-sized ships in Vietnam before each voyage at a low cost instead of using high-cost weather routing services.
Abstract
This research paper introduces a modified single DC-sourced multilevel inverter (MLI) consisting of several cells made from a controlled switch, a diode, and a capacitor to generate voltage levels in series connection with the H-bridge. By increasing the number of cells more output voltage levels can ...
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This research paper introduces a modified single DC-sourced multilevel inverter (MLI) consisting of several cells made from a controlled switch, a diode, and a capacitor to generate voltage levels in series connection with the H-bridge. By increasing the number of cells more output voltage levels can be generated in proposition to 2n+3 for symmetrical multilevel inverter (S-MLI) and maximum 2(N+1) +1 for asymmetrical multilevel inverter (A-MLI), where N is the number of connected cells. In this article, the proposed inverter utilizes seven control switches, three power diodes, a DC voltage source, and three floating capacitors to generate nine-level (S-MLI), fifteen-level, and seventeen-level (A MLI) output. By employing a modified single DC source configuration, we achieve a substantial reduction in the number of isolated DC sources and switches required for operation. The reduction in control switches minimizes the requirement of gate driver and protection circuit. This enhancement not only simplifies the circuitry but also enhances the inverter's cost-effectiveness and efficiency. A comparison of proposed and other recently developed single-sourced topologies has been done to show the benefits of the proposed topology. The performance of the proposed modified inverter topology is analyzed through MATLAB/Simulink and validated by a laboratory prototype. Through extensive simulation and analysis, we demonstrate the improved performance, reduced component count, and complexity of the proposed MLI design.
Abstract
This article describes the use of a sliding mode controller (SMC) in conjunction with an integral (PI) controller for a MLI based DSTATCOM to balance dc side voltage, control a cascaded H-bridge inverter, and compensate for power quality issues related to current harmonics. Several benefits come with ...
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This article describes the use of a sliding mode controller (SMC) in conjunction with an integral (PI) controller for a MLI based DSTATCOM to balance dc side voltage, control a cascaded H-bridge inverter, and compensate for power quality issues related to current harmonics. Several benefits come with using SMC for DSTATCOMDC link voltage regulation, including a decrease in switching ripple in the DC side voltage and a steady DC side capacitor voltage under dynamic conditions. A DSTATCOM based CHBMLI supplying three phase loads is used to implement the SMC algorithm. When using the suggested dc link voltage balancing method, the DSTATCOM characteristics perform satisfactorily in terms of voltage balancing and the removal of power quality issues such current harmonics. Additionally, the DSTATCOM's improved voltage balancing (IVB) scheme is used to compare the performance of the PI controller with the SMC's improved voltage balancing method. The real-time investigation validates the performance characteristics, and the enhanced voltage balancing scheme of SMC results in better transient and steady state response.
Abstract
This study examines the behavior of carbon nanotube field effect transistors under ballistic conditions by analyzing the effect of gate (αG) and drain (αD) control coefficient modifications on the device’s diameter. The effect of αG and αD on the outcome of carbon nanotube ...
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This study examines the behavior of carbon nanotube field effect transistors under ballistic conditions by analyzing the effect of gate (αG) and drain (αD) control coefficient modifications on the device’s diameter. The effect of αG and αD on the outcome of carbon nanotube field effect transistors (CNTFETs) has been thoroughly investigated, and the performance of the device has been evaluated using a variety of parameters for different diameters. In this CNTFET design, the lowest sub-threshold swing recorded is 60.7 mV/decade when using a lower CNT diameter which is 1 nm. The smaller value of sub-threshold swing is contributed by the highest value of gate control coefficient i.e. 0.98, which is desirable for a better ratio between the on- and off-currents and faster-switching device. Again, the maximum quantum capacitance obtained was 1.97×10−10 F/cm2, utilizing a smaller CNT diameter of 1 nm. The maximum value of quantum capacitance is supplied by the value of the gate control coefficient, which is 0.83. Also, the highest transconductance measured, with a greater CNT diameter of 5 nm, is 14.50 uS. With a gate control coefficient of 0.98, the quantum capacitance reaches its maximum value. Overall, the sub-threshold swing decreases as the gate control coefficient increases, while it increases as the drain control coefficient increases. Again, as the gate control coefficient increases, the value of quantum capacitance decreases with a smaller diameter, whereas the quantum capacitance of the device does not fluctuate significantly with a larger diameter. When the diameter changes, the drain control coefficient undergoes an analogous transformation. Furthermore, an increase in the gate control coefficient causes the transconductance to increase. However, when the drain control coefficient is increased along with a change in diameter, the transconductance value remains almost unchanged. Thus, the ideal values for both control coefficients can be determined in this manner toensure optimal performance.
Abstract
With the digital world booming, so too has the importance of information security. Ensuring safe transmission of data has become paramount, requiring robust mechanisms to navigate potential vulnerabilities. In this context, encryption and watermarking technologies emerge as key players. This article ...
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With the digital world booming, so too has the importance of information security. Ensuring safe transmission of data has become paramount, requiring robust mechanisms to navigate potential vulnerabilities. In this context, encryption and watermarking technologies emerge as key players. This article proposes a groundbreaking method that seamlessly integrates a lightweight encryption scheme with a dedicated watermarking approach for color images. Our proposed technique boasts two key advantages: efficient encryption and successful watermark concealment. The chosen encryption method is computationally light, meaning it requires minimal processing power, yet still effectively shields the embedded watermark. This watermarking process involves a clever two-step transformation. First, the color image is converted into a different color space using the Triangle Vertex Transform (TVT). This lays the groundwork for the second step, where the watermark itself is embedded. For this, we leverage a clever combination of the 2-level Discrete Wavelet Transform (DWT) and the Discrete Cosine Transform (DCT). To gauge the effectiveness of this innovative approach, we put it to the test using popular color images and evaluated it through various metrics. These include standard measures like histogram analysis, correlation, Peak Signal-to-Noise Ratio (PSNR), and Structural Similarity Index (SSIM). These metrics help us understand the success of both the encryption and watermarking aspects. The results speak for themselves: our proposed method achieves an impressive PSNR of 54.4798 dB and a near-perfect SSIM score of 1. This translates to a watermarked image with exceptional quality, practically indistinguishable from the original. Ultimately, this research presents a novel technique that shines in both robustness and imperceptibility, outperforming many existing state-of-the-art methods. This paves the way for safeguarding information with greater efficiency and accuracy, enhancing the reliability of our digital interactions in an increasingly interconnected world.
Abstract
Due to the growing popularity of microgrids in buildings, the foreseeable electricity demand for a building draws the attention of many researchers. The precise short-term demand forecast efficiently directs building managers and operators for interactions with electrical distribution systems, daily ...
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Due to the growing popularity of microgrids in buildings, the foreseeable electricity demand for a building draws the attention of many researchers. The precise short-term demand forecast efficiently directs building managers and operators for interactions with electrical distribution systems, daily operational decisions, and energy conservation. This research proposes a hybrid optimization-based deep learning (DL) approach to increase the accuracy of short-term forecasts. The present work employs the Bilateral Long Short-Term Memory (BiLSTM) network-based DL technique because the BiLSTM technique has an exceptional ability to manage nonlinear interactions in data and learn the temporal dependencies. The performance of the BiLSTM technique is improved by using the optimally determined hyperparameters via a hybrid optimization algorithm that combines particle swarm optimization (PSO) and grey wolf optimization (GWO). The exploration ability of GWO and exploitation ability of PSO are effectively combined in the hybrid optimization GWO-PSO. The performance of the recommended approach is assessed using a case study of an educational building. The performance of the proposed model is compared to existing nonoptimal BiLSTM and single optimization-based BiLSTM for short-term load forecast.
Abstract
The main objectify of this article subject is the study and feasibility of micro wind turbine used for small farms, the electrical power generated from an axial flux permanent magnet generator when the power scale is in direct correlation with wind velocity. The proposed design shows more economic costs ...
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The main objectify of this article subject is the study and feasibility of micro wind turbine used for small farms, the electrical power generated from an axial flux permanent magnet generator when the power scale is in direct correlation with wind velocity. The proposed design shows more economic costs with accepted recovered power. The originality of this proposed generator is due to the flexibility and malleability of stator windings’ various positions connection whichallowed it to pass from the signal phase to multiphase generator. The mechanical coupling between the generator and wind turbine is a direct drive system without mechanical gear when the rotor is designed to excite the stator from hollow disc permanent magnets. However, the generator electromagnetic model study with finite element analyses is carried out in three dimensions thanks to Flux3D accuracy software. The simulation results assent to the forefront of a decision to proceed with primary experimental tests on the designed prototype.
Abstract
For transformer-less operation, a wind energy generating system (WEGS) with an 8.5 kW wind turbine and a 6.6 kW Z-source inverter (ZSI) is modelled. A closed-loop control technique is employed at the load side of the WEGS to obtain a constant voltage with a fluctuating load at the output side of the ...
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For transformer-less operation, a wind energy generating system (WEGS) with an 8.5 kW wind turbine and a 6.6 kW Z-source inverter (ZSI) is modelled. A closed-loop control technique is employed at the load side of the WEGS to obtain a constant voltage with a fluctuating load at the output side of the system. The ZSI is used with a proportional-integral (PI) controller for closed-loop control since it is the least complicated controller to operate and tune. As an effect ofZSI’s nonlinear nature, PI controllers cannot be used directly with this system. The primary focus of this study is the optimization of stabilized PI coefficients (Kp, Ki). PI tuning for closed-loop ZSI is taken care of with the use of particle swarm optimization (PSO), the sine-cosine algorithm (SCA), and the opposition-based sine-cosine algorithm (OB-SCA). The OB-SCA provides superior closed-loop ZSI stability when used with WEGS. MATLAB is used for both the design andsimulation of the system. The results demonstrate that the proposed controller can precisely regulate the AC output voltage of ZSI with WEGS.
Abstract
This paper aims to investigate the performance of a bidirectional DC-DC converter utilizing an ANFIS-PID controller in closed-loop mode. This is because operating a bidirectional DC-DC converter in open-loop mode can result in several problems, including poor regulation, limited flexibility, and limited ...
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This paper aims to investigate the performance of a bidirectional DC-DC converter utilizing an ANFIS-PID controller in closed-loop mode. This is because operating a bidirectional DC-DC converter in open-loop mode can result in several problems, including poor regulation, limited flexibility, and limited performance, especially in transient response and efficiency. Additionally, there is a risk of overloading the converter or damaging connected devices due to uncontrolledoperation. Therefore, the main objective of this study is to address the critical requirement for enhanced response and load efficiency within the context of a three-phase interleaved bidirectional DC-DC converter designed for Hybrid Electric Vehicle (HEV) applications with 1 kW rated power of converter and 10 kHz switching frequency which exhibits 14.29% reduce overshoot in the system. This research aims to utilize the capabilities of an ANFIS-PID controller to optimize thedynamic responsiveness and load efficiency of the converter. The findings of the study reveal that the implementation of an ANFIS-PID controller leads to improved transient response and load efficiency, highlighting its potential to enhance bidirectional DC-DC converters. To design and simulate the behavior of the converter, MATLAB/Simulink software has been employed.
