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Background and Objectives: Due to exclusive advantages of the permanent magnet synchronous motors (PMSMs) such as large torque/power density, high efficiency and wide speed range in constant power region, special attention has been paid to these motors especially for electric vehicle (EV) application. A conventional type of PMSMs which is more suitable for EV application is the interior permanent magnet synchronous motors (IPMSM). The main objective of the present paper is design optimization of this type of PMSM to increase efficiency and reduce torque ripple which are important for EV application. Methods: Using different shape design optimization methods including rotor notch, flux barrier and skewed rotor, design optimization of the delta-shape IPMSM is done and an optimized design is suggested first. One of the most important factors affecting the performance of the IPMSM is the magnet arrangement in the rotor structure. Based on the design of experiments (DOE) algorithm, optimal values of some design parameters related to magnet are then determined to improve more the motor performance of the suggested structure. Results: The simulation results based on finite element method (FEM) are provided for a typical high-power IPMSM to evaluate the effectiveness of the proposed technique. In comparison to the initial design, 7% increase of average torque, 50% reduction of torque ripple and 1.4% increase of efficiency are resulted for the optimized motor. Conclusion: Using the proposed hybrid design optimization procedure (shape design optimization with optimum design parameters), significant improvement of some characteristics related to the delta-shape IPMSM including efficiency, average torque and torque ripple is resulted and this conclusion is desirable for EV application. [ABSTRACT FROM AUTHOR]

In this paper, modular design of embedded feedback controllers using field-programmable gate array (FPGA) technology is studied. To this end, a novel distributed-arithmetic (DA)-based proportional-integral-derivative (PID) controller algorithm is proposed and integrated into a digital feedback control system. The DA-based PID controller demonstrates 80% savings in hardware utilization and 40% savings in power consumption compared to the multiplier-based scheme. It also offers good closed-loop performance while using less resources, resulting in cost reduction, high speed, and low power consumption, which is desirable in embedded control applications. The complete digital control system is built using commercial FPGAs to demonstrate the efficiency. The design uses a modular approach, so that some modules can be reused in other applications. These reusable modules can be ported into Matlab/Simulink as Simulink blocks for hardware/software cosimulation or integrated into a larger design in the Matlab/Simulink environment to allow for rapid prototyping applications. Index Terms--Distributed arithmetic (DA), embedded controllers, field-programmable gate array (FPGA) design, power and speed optimization, proportional-integral-derivative (PID) controller.

Optimal shape design of an interior permanent-magnet (IPM) synchronous motor can substantially reduce its torque pulsation. However, the shape design variations should be feasible and practical. We report on an optimal shape design obtained by drilling small circular holes in the rotor. We found that an optimal location and radius of the holes effectively suppresses the torque pulsation of the IPM drive for various loads under steady-state conditions. The optimal design at rated load is considered as the final design. We use a transient finite-element analysis that is coupled with motion and adequate electric excitation for optimization purposes. An evaluation of the optimal design at various operating conditions showed torque ripple reduction and average torque improvement under all load conditions. The optimal design also shows improvement in the field-weakening region for high-speed operation. Index Terms--IPM synchronous motor-drive, shape design optimization, time-stepped finite-element method.

Internet-based telerobotic systems have been evolving rapidly in recent years. Using Web-based technology, telerobotic systems have been shown to have an increasing potential for a variety of applications including remote control, manufacturing, surgery, training, and education. In this paper, we present an Internet-based distributed, multiple-telerobot system that enables operators to use remote robots in order to perform cooperative tasks. Several multiple-telerobot demonstration programs have been designed, including it single telerobot training program, a multiple-telerobot "group object-handling" program, and pairs of telerobots serving Internet participants playing with a Rubik's Cube to illustrate Internet-based interaction and collaboration. Experimental tests have been performed on three demonstration programs that are presented in this paper. Index Terms--Graphical simulation and visualization, Internet-based teleoperation, multiple-telerobots, telerobotics, web-based robotic system.

In this paper, a novel multiobjective optimization method based on a genetic-fuzzy algorithm (GFA) is proposed. The new GFA method is used for optimal design of a switched reluctance motor (SRM) with two objective functions: high efficiency and low torque ripple. The results of the optimal design for an 8/6, four-phase, 4 kW, 250 V, 1500 rpm SRM show improvement in both efficiency and torque ripple of the motor. Index Terms--Multiobjective optimization, SRM design.

This paper addresses data acquisition and feedback control of electron-beam positions in the Duke University Free-Electron Laser Facility. The control system consists of a distributed system of VME-based hardware and processors connected through a network to host workstations. The host workstations provide graphical data presentation to the user and are also used for high-level supervisory control. The electron-beam profile is controlled by electromagnetic forces generated by passing currents through the coils of correction magnets distributed around the ring. A desired control objective is to move the stored electron beam to specific locations in the vacuum chamber and to stabilize the orbit in the presence of disturbances. The technical details of implementing the data acquisition and control scheme and their integration with the existing control system modules are presented along with experimental results. Index Terms--Attenuation, data acquisition, distributed computing, feedback systems, free-electron lasers, stability.

A transformation technique in conjunction with coupled magneto-thermal FE field analysis is used to obtain temperature distribution profile of underground power cables. The transformation technique is used to limit the open region of the solution space, resulting in more accurate solutions with fewer mesh elements and less computing time than that required by open boundary FE solution. Two test problems have been solved and the results are compared with the results obtained from lumped resistive and open boundary FE methods. Index terms - Coupled field analysis, Finite element method

The Magnetic Equivalent Circuit (MEC) method has been used to model the nonlinear magnetic field in electromagnetic devices for steady-state and dynamic conditions. However for highly saturated electromagnetic device, the conventional MEC method is inaccurate in predicting device characteristics. With experience gained from the Finite Element (FE) method, the MEC method can be modified to provide significant accuracy improvement in the field solution results. The main modification is done in the modeling of the highly saturated regions. The Improved Magnetic Equivalent Circuit (IMEC) is used to predict the characteristics of a Switched Reluctance Motor (SRM). The results from IMEC are compared with those obtained by conventional MEC, FE methods, and measurement. Index terms - Magnetic circuits, electromagnetic devices, nonlinear analysis.

In this paper, a novel multi-objective optimization method based on Genetic-Fuzzy Algorithm (GFA) is proposed. GFA is applied to optimize the five PI controller gains in the Indirect Field Oriented Control (IFOC) of an induction motor drive. The PI controller gains are designed to optimize the step response of the system. Rise-time, maximum over-shoot, setting time and steady state error are the objective functions. In this drive system, the simultaneous estimation of the rotor speed and time constant for a voltage source inverter-fed induction motor is discussed. The theory is based on the parallel Model Reference Adaptive Control System (MRAC). The vector control of the induction motor may be achieved in the rotor-flux-oriented frame. Furthermore, to eliminate the offset error caused by the change in the stator resistance, a fuzzy resistance is also designed. The simulation results of the new method for induction motor speed control is compared with the results obtained by the conventional method, which shows better performance. Index Terms--Genetic algorithm, genetic-fuzzy algorithm, indirect field oriented control, multi-objective optimization.

In this paper, a phenomenon is presented that severely restricts control of end-point force via actuation at the other end in a constrained very flexible single-link arm. This limitation is different from and can be more severe than its known non-minimum-phase characteristic. The link flexibility, contact compliance, and stick–slip friction forces at the hub and end-point areas are incorporated into a unique dynamic model and individual effects of friction forces at the hub and the tip on the control performance are investigated. Experimental results are presented to verify the phenomenon and evaluate the validity of the proposed model. [ABSTRACT FROM PUBLISHER]

In this paper, modular design of embedded feedback controllers using field-programmable gate array (FPGA) technology is studied. To this end, a novel distributed-arithmetic (DA)-based proportional—integral—derivative (PID) controller algorithm is proposed and integrated into a digital feedback control system. The DA-based PID controller demonstrates 80% savings in hardware utilization and 40% savings in power consumption compared to the multiplier-based scheme. It also offers good closed-loop performance while using less resources, resulting in cost reduction, high speed, and low power consumption, which is desirable in embedded control applications. The complete digital control system is built using commercial FPGAs to demonstrate the efficiency. The design uses a modular approach, so that some modules can be reused in other applications. These reusable modules can be ported into Matlab/Simulink as Simulink blocks for hardware/software cosimulation or integrated into a larger design in the Matlab/Simulink environment to allow for rapid prototyping applications. [ABSTRACT FROM AUTHOR]

Internet-based telerobotic systems have been evolving rapidly in recent years. Using Web-based technology, telerobotic systems have been shown to have an increasing potential for a variety of applications including remote control, manufacturing, surgery, training, and education. In this paper, we present an Internet-bused distributed, multiple-telerobot system that enables operators to use remote robots in order to perform cooperative tasks. Several multiple-telerobot demonstration programs have been designed, including a single telerobot training program, a multiple-telerobot "group object-handling" program, and pairs of telerobots serving Internet participants playing with a Rubik's Cube to illustrate Internet-based interaction and collaboration. Experimental tests have been performed on three demonstration programs that are presented in this paper. [ABSTRACT FROM AUTHOR]

Focuses on a study that introduced a multi-objective optimization index for improving the dynamic behavior of an actuated structurally flexible arm through geometric shape design. Information on flexural dynamics and eigenvalue sensitivities; Discussion on multi-objective optimization; Optimization procedure and discussion of results; Conclusion of the study.

Introduction: Diazinon is a moderately toxic broad-spectrum organophosphate, with a LD50 of 350 to 400 mg/kg for humans. It is largely used for pest control in Iran. As an acetyl cholinesterase inhibitor (ChE) it inhibits acetylcholine (Ach) hydrolysis at the never endings. Accumulation of Ach stimulates muscarinic and nicotinic receptors causing morbidity and mortality. Diazinon is absorbed through the skin and gastrointestinal tract and is rapidly metabolized within a few hours. Objective: Diazinon residue in melons and cucumbers has recently been a health concern in Iran. It was thus aimed to investigate Diazinon residues in melon and cucumbers. Method: Twenty melons and cucumbers were randomly purchased from the market in Mashhad. The extraction procedure was in HR-P columns preconditioned with methanol and water. The subsequent elution of diazinon was performed with a mixture of hexane-ethyl acetate (1:1, v/v) prior to the determination by GC-NPD and GC-MS/MS. Standards were prepared spiking blank juice samples to contract the observed matrix effect. Accuracy (<9.6%), precision (<7.1%), specificity (quantitative, no peaking intraction), sensitivity (LOD 0.1ng/ml and LOQ 5ng/ml) and reproducibility (<95.4%) were acceptable. Detection limit was 1ng/ml. Linear relation with good correlation coefficients (R2 > 0.99) was obtained. Results: Mean recovery for diazinon was 95.4% with relative standard deviation lower than 9% in the concentration range of 5-200ng/ml. Mean and SD of diazinon in melons was 107.64±38.5 ng/kg. Diazinon was not detected in cucumber samples. It was later confirmed that diazinon was not used for the crops of these cucumbers. Conclusions: GC-NPD and MS/MS was developed to determine residue of diazinon in melons and cucumbers. The GC-MS/MS analytical method showed a high efficacy for determination of diazinon residues in the fruits. [ABSTRACT FROM AUTHOR]

Purpose: This systematic review aims to consolidate key findings regarding the efficacy of pain relief medications administered prior to pan-retinal photocoagulation (PRP) for diabetic retinopathy (DR)., Methods: A comprehensive search of major databases from 1993 to 2023 was conducted. Clinical trials comparing pain relief drugs before PRP in patients diagnosed with DR requiring PRP treatment were eligible for inclusion. The assessment of pain scores involved the use of various scales, such as the visual analog scale (VAS), numerical rating scale (NRS), verbal rating scale (VRS), and other ordinal pain scales. In addition, laser parameters were taken into consideration during the analysis., Results: Twenty-two clinical trials from initial 150 studies were included in the review. Nine studies evaluated the pain relief effects of nonsteroidal anti-inflammatories NSAIDs (selective NSAID and nonselective NSAID), two studies compared the effects of opioids (conventional opioids and atypical opioids), and eleven studies investigated the effects of benzodiazepines, lidocaine, and other sedatives., Conclusion: This review synthesizes findings from multiple studies reporting pain as an adverse outcome of PRP in patients with advanced DR. Based on the evidence from reviewed clinical trials, the administration of lidocaine 2% via transconjunctival, retrobulbar, or peribulbar block along with specific NSAIDs, such as topical ketorolac administrated 24 hours before treatment or oral diclofenac potassium (50 mg) prior to PRP, demonstrated beneficial effects among patients with DR., Competing Interests: The authors report no commercial or proprietary interest in any product or concept discussed in this article., (Copyright © 2024 Mohammadkarim Johari et al.)

Introduction: Small bowel obstruction (SBO) is known as a common cause of acute abdominal complaints in the emergency department (ED). The modality of choice for the diagnosis of SBO has not yet been established. This systematic review and meta-analysis aimed to investigate the accuracy of ultrasonography for the diagnosis of SBO., Methods: Systematic search was performed on five electronic databases including Medline, Scopus, Web of Sciences, Embase, and Cochrane Library, and the retrieval period was from the inception of each database to November 2023. The quality of the included studies were investigated using the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2). The pooled values of diagnostic characteristics for ultrasonography were estimated using meta-Disc and Stata statistical software., Results: Twenty-one studies with a total of 1977 patients were included in the meta-analysis. The pooled estimate for sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and area under the summary ROC curve of ultrasonography for diagnosing SBO were 0.93 (95% CI: 0.91-0.95), 0.8 (95% CI: 0.77-0.83), 5.69 (95% CI: 3.64-8.89), 0.1 (95% CI: 0.07-0.16), 83.51 (95% CI: 18.12-182.91) and 0.96, respectively., Conclusion: The findings of this meta-analysis showed that the utilization of ultrasonography holds promise as a diagnostic imaging for SBO with high accuracy. However, additional worldwide studies are essential to get more evidence on the value of ultrasonography for the diagnosis of SBO., Competing Interests: None.

The steady-state levels of protein sumoylation depend on relative rates of conjugation and desumoylation. Whether SUMO modifications are generally long-lasting or short-lived is unknown. Here we show that treating budding yeast cultures with 1,10-phenanthroline abolishes most SUMO conjugations within one minute, without impacting ubiquitination, an analogous post-translational modification. 1,10-phenanthroline inhibits the formation of the E1~SUMO thioester intermediate, demonstrating that it targets the first step in the sumoylation pathway. SUMO conjugations are retained after treatment with 1,10-phenanthroline in yeast that express a defective form of the desumoylase Ulp1, indicating that Ulp1 is responsible for eliminating existing SUMO modifications almost instantly when de novo sumoylation is inhibited. This reveals that SUMO modifications are normally extremely transient because of continuous desumoylation by Ulp1. Supporting our findings, we demonstrate that sumoylation of two specific targets, Sko1 and Tfg1, virtually disappears within one minute of impairing de novo sumoylation. Altogether, we have identified an extremely rapid and potent inhibitor of sumoylation, and our work reveals that SUMO modifications are remarkably short-lived., (© 2024. The Author(s).)

Bacterial leaf streak of small-grain cereals is an economically important disease of wheat and barley crops. The disease occurs in many countries across the globe, with particular importance in regions characterized by high precipitation or areas in which sprinkler irrigation is used. Three genetically distinct lineages of the Gram-negative bacterium Xanthomonas translucens ( X. translucens pv. undulosa , X. translucens pv. translucens , and X. translucens pv. cerealis ) are responsible for most of the bacterial leaf streak infections on wheat and barley crops. Considering the seedborne nature of the pathogens, they are included in the A2 (high-risk) list of quarantine organisms for some European countries; hence, they are under strict quarantine control and zero tolerance. Due to the taxonomic complexities within X. translucens , the exact geographic distribution of each pathovar has not yet been determined. In this mini review, we provide an updated overview of the detection and diagnosis of the bacterial leaf streak pathogens. First, a short history of the leaf streak pathogens is provided, followed by the symptomology and host range of the causal agents. Then, the utility of conventional methods and high-throughput molecular approaches in the precise detection and identification of the pathogens is explained. Finally, we highlight the role of quarantine inspections and early detection of the pathogen in combating the risk of bacterial leaf streak in the 21st century's small-grains cereals' industry., Competing Interests: The author(s) declare no conflict of interest.

We present a high-performance capacitive accelerometer with a sub-µg noise limit and 1.2 kHz bandwidth for particle acceleration detection applications. The low noise of the accelerometer is achieved through a combination of device design optimization and operation under vacuum to reduce the effects of air damping. Operation under vacuum, however, causes amplification of signals around the resonance region, potentially resulting in incapacitating it through saturation of interface electronics or nonlinearities and even damage. The device has thus been designed with two sets of electrodes for high and low electrostatic coupling efficiency. During normal operation, the open-loop device utilizes its high-sensitivity electrodes to provide the best resolution. When a strong signal near resonance is detected, the electrodes with low sensitivity are used for signal monitoring, while the high-sensitivity electrodes are used to apply feedback signals efficiently. A closed-loop electrostatic feedback control architecture is designed to counteract the large displacements of the proof mass near resonance frequency. Therefore, the ability to reconfigure electrodes lets the device be used in high-sensitivity or high-resiliency modes. Several experiments were conducted with DC and AC excitation at different frequencies to verify the effectiveness of the control strategy. The results showed a ten-fold reduction of displacement at resonance in the closed-loop arrangement compared to the open-loop system with a quality factor of 120.

Mycopathogenic bacteria play a pivotal role in the productivity of edible mushrooms grown under controlled conditions. In this study, we carried out a comprehensive farm survey and sampling (2018 to 2021) on button mushroom ( Agaricus bisporus ) farms in 15 provinces in Iran to monitor the status of bacterial pathogens infecting the crop. Mycopathogenic bacterial strains were isolated from pins, stems, and caps, as well as the casing layer on 38 mushroom farms. The bacterial strains incited symptoms on mushroom caps ranging from faint discoloration to dark brown and blotch of the inoculated surfaces. Among the bacterial strains inciting disease symptoms on bottom mushroom, 40 were identified as Ewingella americana based on biochemical assays and phylogeny of 16S rRNA and the gyrB gene. E. americana strains differed in their aggressiveness on mushroom caps and stipes, where the corresponding symptoms ranged from deep yellow to dark brown. In the phylogenetic analyses, all E. americana strains isolated in this study were clustered in a monophyletic clade closely related to the nonpathogenic and environmental strains of the species. BOX-PCR-based fingerprinting revealed intraspecific diversity. Using the cutoff level of 73 to 76% similarity, the strains formed six clusters. A chronological pattern was observed, where the strains isolated in 2018 were differentiated from those isolated in 2020 and 2021. Taken together, due to the multifaceted nature of the pathogen, such a widespread occurrence of E. americana on mushroom farms in Iran could be an emerging threat for the mushroom industry in the country.