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This article presents a novel Cyber-Hardware-in-the-Loop (Cyber-HIL) platform for assessing control operation in ship cyber-physical systems. The proposed platform employs cutting-edge technologies, including Docker containers, real-time simulator $OPAL-RT$, and network emulator $ns3$, to create a secure and controlled testing and deployment environment for investigating the potential impact of cyber attack threats on ship control systems. Real-time experiments were conducted using an advanced load-shedding controller as a control object in both synchronous and asynchronous manners, showcasing the platform's versatility and effectiveness in identifying vulnerabilities and improving overall Ship Cyber Physical System (SCPS) security. Furthermore, the performance of the load-shedding controller under cyber attacks was evaluated by conducting tests with man-in-the-middle (MITM) and denial-of-service (DoS) attacks. These attacks were implemented on the communication channels between the controller and the simulated ship system, emulating real-world scenarios. The proposed Cyber-HIL platform provides a comprehensive and effective approach to test and validate the security of ship control systems in the face of cyber threats.

Sub-harmonic synchronous machines (SHSMs) are a relatively new breed of brushless wound field synchronous machines considered alternatives to many electric machines in transportation electrification applications. This article presents two dual inverter SHSMs (DI-SHSMs) having unique two-layer and three-layer stator winding topologies. The two inverters provide the stator windings with two sets of balanced three-phase currents. These two and three-layer windings are arranged in such a way that they can generate both fundamental and sub-harmonic magnetomotive force (MMF). Furthermore, the fundamental MMF component of this machine is four times the sub-harmonic MMF component used for the brushless operation. In contrast, the sub-harmonic MMF is used for field excitation, which leads to brushless operation. Two eight-pole, 48-slot, two-inverter, two-layer, and three-layer sub-harmonic machines are designed to validate the concept through a 2-D finite element analysis (FEA) of these new topologies, showing a better overall torque profile and performance as compared with the other sub-harmonic and brushless wound field synchronous machines.

The use of high frequency power converters to enhance power density and energy efficiency has become widely used in grid-connected hybrid DC microgrids. This article presents a new modularized high frequency DC-link integration methodology that connects multisource renewable energy sources involving battery energy storage system (BESS) to the AC-grid. A grid-tie-inverter with a line inductor is introduced to control the active-reactive power flow. To minimize the converter physical size with improved system efficiency, a high frequency-based front-end multisource bridgeless boost (MBB) architecture is proposed here. A direct-mount decoupling snubber capacitor and a soft switching are used to reduce the switching losses resulting from the high-frequency operation. The performance of the proposed system is investigated. A direct digital approach is used to design the system controller in MATLAB/Simulink R2022a environment. To validate the system performance, a 10 kW multi-source grid-connected experimental setup with dSPACE-1104 controller is constructed, tested, and compared with other conventional topologies. The test results verify the proposed topology effectiveness for hybrid grid-connected renewable energy resources integration.

This article adopts a novel technique to numerical solution for fractional time-delay diffusion equation with variable-order derivative (VFDDEs). As a matter of fact, the variable-order fractional derivative (VFD) that has been used is in the Caputo sense. The first step of this technique is constructive on the construction of the solution using the shifted Legendre–Laguerre polynomials with unknown coefficients. The second step involves using a combination of the collocation method and the operational matrices (OMs) of the shifted Legendre–Laguerre polynomials, as well as the Newton–Cotes nodal points, to find the unknown coefficients. The final step focuses on solving the resulting algebraic equations by employing Newton’s iterative method. To illustrate and demonstrate the technique’s efficacy and applicability, two examples have been provided.

In this paper, a novel encoderless control of permanent magnet assisted synchronous reluctance generator (PMa-SynRG) based-stator current vector for renewable energy systems is presented. For the encoderless control, the PMa-SynRG rotor position angle along with rotor angular speed are estimated ultimately from the generator's stator currents, as the stator inductance is only requisite nevertheless the stator resistance. Indeed, this encoderless control technique employs one current control loop for regulating the magnitude of the stator current instead of employing two current control loops. For eliminating the current measurement noise and enhancing the phase angle tracking performance, a modified second-order generalized integrator frequency-locked loop (MSOGI-FLL) technique is employed and compared with the standard SOGI-FLL under different voltage/frequency conditions. The proposed technique has a simple computational implementation while accomplishing a rapid along with precise estimation performance of the PMa-SynRG rotor position angle and speed. The performance is validated using simulations and real-time hardware-in-the-loop Typhoon HIL implementation.

The necessity of critical communication between intelligent electronic devices (IEDs) in different substations led to expanding the Generic Object-Oriented Substation Event protocol (GOOSE) from the local area network (LAN) to the wide area network (WAN). International Electrotechnical Commission (IEC) 61850-90-5 has extended GOOSE messages as routable GOOSE (R-GOOSE) messages by adding network and transport layers. Therefore, the communication’s end-to-end latency and reliability against cyberattacks should be addressed.

The main goal of cyber-physical power systems (CPPSs) is to provide seamless collaboration between the physical and cyber systems, bridging disciplines, such as communication networks and control systems. Controlling the operation of Microgrids (MGs) as a cyber-physical power system must include both the physical and cyber layers. Generally, the microgrid control center MGCC is employed for reliable operation management between the different local controllers within the networked microgrids (NMGs). Therefore, an excessive number of communication channels between the MGCC and the local controllers will exist, affecting the control performance of the NMGs. This paper focuses on developing an innovative communication network emulation model for standalone DC networked microgrids using a Network Simulator (NS3), miming the communication infrastructure to control the networked microgrid system. Through the real-time simulation, the performance of the proposed communication network model was evaluated by employing two transmission protocols, User Datagram Protocol (UDP) and Transmission Control Protocol (TCP), to facilitate the data exchange between the MGCC and the local controllers in each MG while operating under different traffic loads. The comparative results of using these protocols in terms of the key performance indicators (KPIs) of the communication performance metrics, such as the mean delay, percentage of packet loss, and transmitted and received bitrate, reveal notable insights into their suitability in data transmission for controlling and managing the operation of the NMGs.

With the development of nanocarriers, especially in the area of nutraceutical delivery, the rapidly expanding field of nanotechnology has brought in a new age of health and well-being. The revolutionary potential of nanocarriers to improve the stability, bioavailability, and effectiveness of nutraceutical substances is discussed in this review paper. It started with outlining the difficulties that conventional nutraceutical delivery systems have, such as their low solubility and restricted absorption, which frequently obstruct their therapeutic advantages. The various types of nanocarriers which act as nutraceuticals includes liposomes, lipids, and polymer-based materials also highlight of their special qualities and how they get around the problems outlined. Recent developments in nanocarrier technology are critically analyzed to show how these tiny particles may be designed to offer enhanced protection against bioactive compounds and targeted, controlled release. Here toxicity issues and international guidelines compliance while examining safety and regulatory factors relevant to the use of nanocarriers in nutraceuticals has also been discussed. This review concludes with a prospective outlook on the use of nanocarriers in nutraceuticals going ahead, highlighting the possibility of tailored nutrition and the significance of new developments in maintaining and averting illness. This review provides the present status and future prospects of nanocarrier technology in the improvement of nutraceutical delivery by merging recent research findings and expert perspectives.

Batteries are considered critical elements in most applications nowadays due to their power and energy density features. However, uncontrolled charging and discharging will negatively affect their functions and might result in a catastrophic failure of their applications. Hence, a battery management system (BMS) is mandated for their proper operation. One of the critical elements of any BMS is the state of charge (SoC) estimation process, which highly determines the needed action to maintain the battery's health and efficiency. Several methods were used to estimate the Lithium‐ion batteries (LIBs) SoC, depending on the LIBs model or any other suitable technique. This article provides a critical review of the existing SoC estimation approaches and the main LIB models with their pros and cons, their possibility to integrate with each other's for precise estimation results, and the applicability of these techniques in electric vehicles and utility applications with the commonly used standards and codes in these sectors. Moreover, this study will also explore a future framework for integrating digital twins (DTs) with BMSs for improved and advanced management. Based on this comprehensive review, it can be concluded that merging the model‐based estimation techniques with the data‐driven approaches with their promising development to determine the dynamic patterns inside the battery can efficiently achieve precise estimation results while reducing the complexity of these models. This integration will align also with the integration of digital twin technology to provide complete and accurate supervision for the BMSs. This article is categorized under:Emerging Technologies > Energy StorageEmerging Technologies > DigitalizationEnergy and Power Systems > Distributed Generation General function of the battery management system.

Purpose: This study explores the best strategies for regional economic development to attract highly skilled populations, regardless of whether the region is a multisector or unisector economic hub. It also determines the development variables affecting the success of integrated regional economic hubs to achieve spatial equality, enhance economic productivity and attain environmental sustainability. Design/methodology/approach: In addition to a qualitative analysis, this study employed quantitative techniques using SPSS software. This allowed amplification of the most significant explanatory variables affecting the weaknesses and strengths of economic hubs. Findings: The results highlight approaches that can be used to achieve socio-economic sustainability in regional hubs. These include multisectors or main centralised hubs (smart economic regional capital), which provide new services to regions and act as a unidevelopment sector or as a regional, economic capital. Research limitations/implications: The study analyses the effect of economic strategies and integration of natural resources and the required core services in regional economic development. Practical implications: Case studies of successful economic hubs are discussed. The most important services proposed in such hubs promote human development and increase the standard of living. Social implications: Integration between the hubs in a region is fundamental to attracting direct investments that can benefit the local population. Originality/value: The results could help governments, economists and planners implement multisector developmental hubs to achieve sustainable development.

In this paper, a new single-switch transformerless boost dc–dc converter is proposed for fuel cell vehicles. The developed topology utilizes a switched-capacitor multiplier and an integrated LC $^{2}D$ output network in order to enhance the voltage gain of the converter and reduce the voltage stress on the power switch. In addition, the proposed converter has a wide voltage gain range to suit the wide voltage swings of the fuel cell. The operating principles and the steady-state analyses of the proposed converter when it operates in continuous conduction mode (CCM) and discontinuous conduction mode (DCM) are illustrated in this paper. Additionally, the dynamic modeling and the compensator design for the developed converter are discussed. A scaled-down 800-V, 1.3-kW experimental prototype was built using a gallium nitride (GaN) transistor and silicon carbide (SiC) diodes to validate the theoretical analyses of the proposed converter.

This paper proposes a decentralized control algorithm for the medium-voltage direct current (MVDC) shipboard storage system to enhance the onboard survivability. The algorithm takes decisions based on local measurements, which makes it robust against cyber-attacks and able to provide a fast response. The voltage profile of the MVDC bus has sufficient information about the system status, which is utilized for managing the hybrid energy storage systems. Insertion/removal of the storage devices, such as batteries and supercapacitors, is made according to the mathematical morphology-based voltage processing and state-machine logic algorithms. To ensure proper power sharing, an adaptive droop control is used, taking into account consideration the state-of-charge of the storage units. Field-programmable gate array in the loop validation results confirms the ability of the proposed controller to maintain the MVDC bus voltage and the adequate operation of the storage entities simultaneously.

An integrated interleaved dc-dc converter with ultrahigh voltage gain and reduced voltage stress based on the coupled-inductors and switched-capacitor circuits is proposed in this article, which is suitable for interfacing the low-voltage energy sources, such as fuel-cell, with a high-voltage dc bus in electric vehicle applications. Input-parallel connection of the coupled-inductors offers a reduced input current ripple and the current rating of components, as well as automatic input current sharing without a dedicated current sharing controller. A promising power-density improvement technique is given, in which only one magnetic core is utilized to implement two coupled-inductors that can provide the filter functionality, as well as transformer behavior. For suppressing the voltage ringing resulting from the leakage inductors, the active-clamp configuration is employed that can facilitate the soft-switching performance for all switches in a wide range of output power. A voltage multiplier stage is adapted to not only boost the voltage gain but help alleviate the reverse-recovery problem of diodes. The steady-state performance, theoretical analysis, and a comparison with the state-of-the-art converters are given in this article. Finally, the experimental results of a 1-kW, 100-kHz prototype are provided to confirm the validity of the proposed concept.

ABSTRACTThis study aimed to determine aflatoxin M1 (AFM1) in dairy sheep, goats, and camel milk in Hail, Saudi Arabia, and evaluate methods for reducing AFM1. A total of 67 milk samples were collected from Ghazala and Al-Shweimis villages, Hail. AFM1 in milk samples was analyzed using enzyme-linked immunosorbent assay (ELISA) and high-performance liquid chromatography (HPLC) with fluorescence detection. Results revealed concentration of AFM1 in goat and camel milk samples from Ghazala was higher than that in goat and camel milk samples from Al-Shweimis with a significant difference (p<0.05) using both ELISA and HPLC methods. The mean AFM1 concentration using ELISA for goat milk was (12.96 ± 2.23 ng/l), while the AFM1 concentration for camel milk was (1.54 ± 0.29 ng/l). Microwave heating and boiling are effective methods to reduce the AFM1 in milk. ‏‎‏‎‏The highest AFM1 removal percent was 42.96% by microwave and 12.32 % by boiling milk samples.

•Small signal model for a MVDC power system and design of a model predictive controller.•The purpose is to maintain the voltage stability and ensures proper power sharing among ESS.•The small signal model of the system is embedded inside the controller.•That will increases the flexibility of the controller to adapt to the different circumstances.

Gallium nitride (GaN) high-electron mobility transistors (HEMTs) are a promising technology for high-efficiency and high-power density applications. In this paper, a stacked three-port three-level converter (STPTLC) using GaN switches is proposed for interfacing the renewable energy sources (RESs) with load for applications that the presence of energy storage device is necessary. Derived from the asymmetrical bidirectional half-bridge (ABHB) converter, the proposed converter presents valuable advantages in terms of simple control scheme, extended soft-switching over a wide range of operating conditions, and reduced voltage stress across switches. The soft-switching for all switches at turn-on instant is guaranteed, thanks to the active clamp configuration, resulting in the high-efficiency performance. The pulsewidth-modulation (PWM) plus phase-shift control technique paves the way for decoupled regulation of the output voltage and power by presenting two control freedoms, which allows the input voltage to vary in a wide range. To diminish the current stress of switches and minimize the conduction loss, the root-mean-square (rms) current of inductance and the boundary condition of the phase-shift controller in different operation cases are studied. Finally, the experimental results of a 1-kW, 100-kHz prototype of STPTLC using GaN switches are given to confirm the validity of the proposed concept.

Pigeons are a cosmopolitan group of birds with abundant and large populations associated with human activities. This study focused on determining parasitic infections within domestic pigeons (Columba livia domestica). Forty-eight pigeons were examined for infections, of which 29.16% were infected with a nematode parasite, identified as Hadjelia truncata(Habronematidae), under the koilin layer of their gizzards. The population of nematodes in infected gizzards did not exceed 20 adult worms. DNA from the gizzard worms was extracted and subjected to PCR using primers that amplify the partial 18S rDNA and cytochrome C oxidase subunit I (COX I) regions. Identification of this parasite based on microscopic study revealed the presence of trilobed lips with cephalic papillae and amphidial pores, as well as other characteristic features. In males, spicules were unequal with the presence of six pedunculated pairs of caudal papillae (4 pre- and 2 post-anal) and a tail surrounded with caudal ala. In females, the vulva was a rounded aperture located in front of the posterior end of the esophagus and uteri, which was filled with numerous embryonated eggs. DNA Sequences from partial 18S rDNA were homologous to sequences obtained from H. truncatain GenBank with a high percentage of identity. DNA sequences from mitochondrial gene COX I, however, were unique, and they were the first sequenced for H. truncata, since no sequences for this taxon were previously available in GenBank. Histopathological examination revealed enlargement of infected gizzards in comparison to non-infected ones, with the presence of necrosis and interstitial infiltration in the koilin layer. Concentrations of heavy metals (Fe, Cu, Zn, Cd, Cr, and Co) were measured using inductivity-coupled plasma in tissues (liver, muscles, and gizzards) from infected and non-infected pigeons as well as their parasites. Results showed different affinities of metals to tissues. Recovered parasites can minimize element concentration from their pigeon tissues. In Saudi Arabia, this study was considered the first report identifying pigeon nematodes and evaluating of the effects of their pathogenicity on the animals’ welfare, as well as their application as a useful tool for monitoring environmental pollution.

In this paper, distribution systems are optimized to accommodate different renewable energy sources, including PhotoVoltaic (PV) and Wind Turbine (WT) units with existing Electric Vehicles Charging stations (EVCS) connected to specific locations of distribution systems. Battery Energy Storage systems (BES) are provided at the exact locations of the PV and WT units. The BES units are optimized to control the power flow inside the distribution systems and enhance their performance by minimizing the proposed fitness functions. Each BES's generated or consumed power depends mainly on its State of Charge (SoC) and system constraints. The Gorilla Troop Optimizer (GTO) algorithm is adopted to solve the optimization problem either as a single-objective or multi-objective optimization. The adopted fitness functions minimize power loss and total voltage deviation (TVD) of the 108-bus distribution system. Two stages are involved in the GTO solution of the optimization problem. The GTO algorithm finds the ideal positions and sizes of the PV and WT units in the first stage. Then the GTO optimizes the BES operation in the second stage after integrating the EVCS into the system, using distinct profiles with two charging levels on weekdays and weekends. The obtained results show that the percentage reductions in the active energy loss with optimal allocations of the PV/WT are 45.29 % and 45.56 % for Level 1 and Level 2 of EVCS charging. The counterpart reductions increase to 48.22 % and 48.33 % when integrating the BES units. Furthermore, with PV/WT integration, utility power consumptions are reduced by 65.74 % and 65.65 % for the two charging levels, while the reductions increase to 70.63 % and 70.54 % when including BES units. These findings emphasize the importance of optimal BES operation in distribution networks equipped with renewable energy sources. The findings demonstrate the superior capabilities of the GTO algorithm during the optimization phase on an equal footing.

Purpose – The purpose of this paper is to develop a novel technique for the pre-design of a printed circuit board (PCB) of a DC-DC power converters where the placement of electric components can cancel the electromagnetic emissions through subtractive coupling and in this sense to minimize the stray magnetic and electric fields at a specific location. For this work the location of interest is a current transducer used for control purposes positioned in the center of a DC-DC Cuk converter board as a constrain. Design/methodology/approach – The methodology of design is based on the development of an interface software platform through MatLab script coding which interconnects the solution of a numerical analysis software and an optimization technique. The numerical analysis software is based on finite element calculations where quasi-static field analysis are performed to calculate the radiated electric and magnetic fields. The optimization technique is conducted by genetic algorithms (GAs). Findings – The results for the proposed procedure for PCB design show a significant reduction in radiated electromagnetic (EM) field at the susceptible device in the PCB. Even when the optimization procedure is applied only for the sensor center, the field reduction is extended for a wide region around the sensor. The proposed technique not only reduces the fundamental field component but also all the harmonic contents for the electromagnetic field. It is demonstrated that it is possible to cancel the emissions by means of varying the location and orientation of the passive elements avoiding the utilization of electromagnetic interference filters and complex modulations. Originality/value – The novelty of the design procedure falls in the fitness function programming where an interface software platform is built through MatLab scripting to connect a 3D-FE analysis and the GA. The finite element analysis address the radiated EM calculation while the GA focus in the minimization of it. This computational platform has the flexibility to be easily adapted for the PCB design of any power electronic converter where the radiated EM compliance is required as well as extended to perform emissions minimization outside or/and inside the PCB. [ABSTRACT FROM AUTHOR]

Purpose – In this paper, modeling of the XLPE cable for electromagnetic signature study at a far distance is proposed. The paper aims to discuss these issues. Design/methodology/approach – Due to the very small ratio of the dimensions of cables to the dimensions of the whole system, using actual geometry of the cables with all layers in this study causes deformation of the cable's model. Therefore, multi-dipole modeling is used for modeling the cables. Findings – This model includes specific voltages and currents in lines and nodes, respectively. Radiated electric and magnetic fields at a far distance are selected as the index of appropriateness of the model. Originality/value – In order to investigate the accuracy of the model, various configuration of the cable is studied. Additionally, coupling of the cable with an electrical machine is investigated. They all show that the equivalent models can be used in place of the actual model for signature studies. [ABSTRACT FROM AUTHOR]

Using non-destructive sampling we provide further genetic characterisations for spiny mice (Acomys dimidiatus/cahirinus) and gerbils (Gerbillussp.) in three regions in Saudi Arabia. All individuals were sequenced for a fragment of the cytochrome bgene, and compared against available conspecifics and closely related taxa. We confirm the existence of a second Acomys dimidiatus/cahirinuslineage specific to the Arabian Peninsula as seen previously. The Arabian Gerbillus nanusis shown to group with Middle Eastern rather than African conspecifics. A second cryptic Gerbilluslineage was also sampled across multiple locations, which may be an uncharacterised G. dasyurus.

This paper presents an effective algorithm for optimizing the distribution system operation in a smart grid from cost and system stability points of view. This algorithm is mainly dependent on forecasted data of the power available from different renewable energy sources as well as the load demand. Hence, full attention was paid to the forecasting process. A non-linear regression technique was applied to build accurate forecasting models for different sources and load conditions. These models help in monitoring and predicting the total power generation and demand online. The main objective of the optimization process is to control the power shared from different sources such that they satisfy the load demand with the least cost while giving higher priority to renewable energy sources. Moreover, batteries are controlled in such a way that they are allowed to discharge only when there is no very big load predicted within a future period so that they become available to act as a buffer for a predicted large load increase which may affect the stability of the system and hence reduce voltage dips. A fuzzy controller was utilized to determine how many hours before a predicted occurrence of load the battery system should be turned off and what percentage of power should be taken out of the batteries and the grid to solve this issue. Different case studies were investigated to verify the validity of the proposed algorithm and define the system performance under several conditions.

Several studies in Western countries addressed the parental education as directly affecting the academic performance of their children; however, in the Middle East Countries, only a few studies reported this issue. The current study aimed to address the reciprocity of the parental education and academic performance of their children in the medical college of University of Tabuk, Kingdom of Saudi Arabia.

The Arabian oryx lives under hyperarid conditions in the Arabian Desert and exhibits temporal niche switching of activity patterns at a seasonal level. The objective of the current study was to provide a polysomnographic-based study of sleep in free-roaming Arabian oryx in their natural habitat to determine whether extreme seasonal climate variations resulted in changes in sleep patterns and physiology associated with the seasonal switching of temporal niches.

ABSTRACTComplete Middle East respiratory syndrome coronavirus (MERS-CoV) genome sequences were obtained from nasal swabs of dromedary camels sampled in the Kingdom of Saudi Arabia through direct analysis of nucleic acid extracts or following virus isolation in cell culture. Consensus dromedary MERS-CoV genome sequences were the same with either template source and identical to published human MERS-CoV sequences. However, in contrast to individual human cases, where only clonal genomic sequences are reported, detailed population analyses revealed the presence of more than one genomic variant in individual dromedaries. If humans are truly infected only with clonal virus populations, we must entertain a model for interspecies transmission of MERS-CoV wherein only specific genotypes are capable of passing bottleneck selection.IMPORTANCEIn most cases of Middle East respiratory syndrome (MERS), the route for human infection with the causative agent, MERS coronavirus (MERS-CoV), is unknown. Antibodies to and viral nucleic acids of MERS-CoV have been found in dromedaries, suggesting the possibility that they may serve as a reservoir or vector for human infection. However, neither whole viral genomic sequence nor infectious virus has been isolated from dromedaries or other animals in Saudi Arabia. Here, we report recovery of MERS-CoV from nasal swabs of dromedaries, demonstrate that MERS-CoV whole-genome consensus sequences from dromedaries and humans are indistinguishable, and show that dromedaries can be simultaneously infected with more than one MERS-CoV. Together with data indicating widespread dromedary infection in the Kingdom of Saudi Arabia, these findings support the plausibility of a role for dromedaries in human infection.

During the course of acute viral hepatitis, some functional and anatomical changes to the gallbladder can occur. Acute acalculous cholecystitis (ACC) is a rare complication of acute hepatitis B virus infection; only few cases are reported as ACC associated with acute hepatitis B virus infection. ACC cases are self-limiting, while other limited cases can progress to a gangrenous state, perforation, and even death. We present a 27-year-old female case diagnosed to have acute acalculous cholecystitis and associated with acute hepatitis B virus infection, and she recovered within one week of her presentation without complication or surgical intervention.

The article describes progress towards measles elimination in the Eastern Mediterranean Region (EMR) made during 2013-2019. Topics mentioned include an increase in estimated regional measles-containing vaccine coverage during 2013-2018, attributes of measles supplementary immunization activities, and a decrease in the number of reported measles cases in the EMR between 2013 and 2014.