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Ferroresonance, as an undesirable disturbance, leads to significant overvoltage and distorted waveforms. This phenomenon can be highly damaging to voltage transformers and other parallel-connected equipment and can entail catastrophic consequences. This paper aims to design and study a solid-state ferroresonance-suppressing circuit (SSFSC) to protect voltage transformers (VTs) together with other parallel-connected equipment in wind generation systems from the adverse effects of the ferroresonance phenomenon. The proposed structure consists of low-voltage circuits, including power IGBTs. The excellent performance of the proposed SSFSC in suppressing ferroresonance overvoltage in wind generation VTs has been authenticated by analyses conducted utilizing a wind generation system model. In order to validate the performance of the proposed SSFSC, detailed analytical studies and time-domain simulations have been carried out employing a MATLAB/Simulink environment. The results verify that the proposed SSFSC can effectively suppress ferroresonance phenomena in VTs and mitigate their accompanying overvoltages with a high operational speed., Intelligent Electrical Power Grids

Many seismic studies treat a vehicle-bridge coupled system as a bridge-TMD (tuned-mass damper) system, and, unsurprisingly, have found that the vehicle usually reduces the seismic response of the bridge. The current study challenges this notion by looking deeper into how a vehicle in motion influences the seismic performance of the bridge that it traverses. Specifically, the analysis explores the underlying physical mechanisms of vehicle-bridge interaction (VBI) and TMD, identifies the dominant terms in each system, and highlights both their similarities and differences. In this context, the study compares via pertinent numerical simulations the effect of a moving vehicle versus a stationary vehicle on the bridge, under a set of natural earthquake records along solely the vertical direction. The study also shows how the vehicle’s speed and timing (i.e., time difference between a vehicle’s entry to the bridge and the earthquake’s occurrence) influence the seismic response of the bridge.

An increasing number of artificial intelligence (AI) applications involve the execution of deep neural networks (DNNs) on edge devices. Many practical reasons motivate the need to update the DNN model on the edge device post-deployment, such as refining the model, concept drift, or outright change in the learning task. In this paper, we consider the scenario where retraining can be done on the server side based on a copy of the DNN model, with only the necessary data transmitted to the edge to update the deployed model. However, due to bandwidth constraints, we want to minimise the transmission required to achieve the update. We develop a simple approach based on matrix factorisation to compress the model update -- this differs from compressing the model itself. The key idea is to preserve existing knowledge in the current model and optimise only small additional parameters for the update which can be used to reconstitute the model on the edge. We compared our method to similar techniques used in federated learning; our method usually requires less than half of the update size of existing methods to achieve the same accuracy., Comment: CVPR 2022 Mobile AI Workshop

Several types of high voltage direct current (HVDC) breakers have been introduced and commercialized. Each of them has advantages and disadvantages. Among them, the hybrid HVDC breaker is highly successful. One of the most important concerns that the hybrid HVDC breaker has faced is high power loss throughout its fault current breaking process. The hybrid HVDC breaker comprises a high voltage bidirectional main HVDC breaker. A significant number of electronic switches need to be connected in a series where anti-parallel diodes are essentially embraced. During fault inception, a number of series solid-state switches and a number of series diodes dramatically increase the power loss of the main breaker. This study, firstly, studies the power loss of the hybrid HVDC breaker and later develops a structure of a full-bridge hybrid breaker (FBHB) to reduce the losses of the current structure both in the normal and fault protection states. In this paper simulations are done based on PSCAD. In addition to the analytical study and simulations, we show that the developed structure substantially decreases the amount of power lost during the normal operation and fault current breaking stage.

Several types of high voltage direct current (HVDC) breakers have been introduced and commercialized. Each of them has advantages and disadvantages. Among them, the hybrid HVDC breaker is highly successful. One of the most important concerns that the hybrid HVDC breaker has faced is high power loss throughout its fault current breaking process. The hybrid HVDC breaker comprises a high voltage bidirectional main HVDC breaker. A significant number of electronic switches need to be connected in a series where anti-parallel diodes are essentially embraced. During fault inception, a number of series solid-state switches and a number of series diodes dramatically increase the power loss of the main breaker. This study, firstly, studies the power loss of the hybrid HVDC breaker and later develops a structure of a full-bridge hybrid breaker (FBHB) to reduce the losses of the current structure both in the normal and fault protection states. In this paper simulations are done based on PSCAD. In addition to the analytical study and simulations, we show that the developed structure substantially decreases the amount of power lost during the normal operation and fault current breaking stage.

Several types of high voltage direct current (HVDC) breakers have been introduced and commercialized. Each of them has advantages and disadvantages. Among them, the hybrid HVDC breaker is highly successful. One of the most important concerns that the hybrid HVDC breaker has faced is high power loss throughout its fault current breaking process. The hybrid HVDC breaker comprises a high voltage bidirectional main HVDC breaker. A significant number of electronic switches need to be connected in a series where anti-parallel diodes are essentially embraced. During fault inception, a number of series solid-state switches and a number of series diodes dramatically increase the power loss of the main breaker. This study, firstly, studies the power loss of the hybrid HVDC breaker and later develops a structure of a full-bridge hybrid breaker (FBHB) to reduce the losses of the current structure both in the normal and fault protection states. In this paper simulations are done based on PSCAD. In addition to the analytical study and simulations, we show that the developed structure substantially decreases the amount of power lost during the normal operation and fault current breaking stage.

Salt stress is recognized to negatively influence the fundamental processes in plants regarding growth and yield. The sunflower (Helianthus annuus L.) is considered an important industrial crop because of the good quality of oil it produces that can be used for cooking purposes. The exogenous application of potassium (K) has been reported to enhance abiotic resistance and increase yield in crops. Here, we explored the impact of foliar-applied K at 500 ppm on the physiological and biochemical traits, antioxidant activities, and growth attributes of sunflower grown under salt stress (140 mM NaCl). The findings indicated that salinity stress adversely affected photosynthesis and various gas exchange characteristics. Foliar applied K markedly improved the stomatal conductance, transpiration rate, water use efficiency, CO2 assimilation rate, total soluble proteins, chlorophyll pigments, and upregulated antioxidant system, which are responsible for the healthy growth of sunflower hybrids grown under salinity stress. The shoot and root lengths, plant fresh and dry weights, and achene weight were significantly increased by K application. Overall, foliar applied K significantly improved all of the aforementioned attributes and can attenuate the deleterious influences of salinity stress in sunflower.

Salt stress is recognized to negatively influence the fundamental processes in plants regarding growth and yield. The sunflower (Helianthus annuus L.) is considered an important industrial crop because of the good quality of oil it produces that can be used for cooking purposes. The exogenous application of potassium (K) has been reported to enhance abiotic resistance and increase yield in crops. Here, we explored the impact of foliar-applied K at 500 ppm on the physiological and biochemical traits, antioxidant activities, and growth attributes of sunflower grown under salt stress (140 mM NaCl). The findings indicated that salinity stress adversely affected photosynthesis and various gas exchange characteristics. Foliar applied K markedly improved the stomatal conductance, transpiration rate, water use efficiency, CO2 assimilation rate, total soluble proteins, chlorophyll pigments, and upregulated antioxidant system, which are responsible for the healthy growth of sunflower hybrids grown under salinity stress. The shoot and root lengths, plant fresh and dry weights, and achene weight were significantly increased by K application. Overall, foliar applied K significantly improved all of the aforementioned attributes and can attenuate the deleterious influences of salinity stress in sunflower.

Several types of high voltage direct current (HVDC) breakers have been introduced and commercialized. Each of them has advantages and disadvantages. Among them, the hybrid HVDC breaker is highly successful. One of the most important concerns that the hybrid HVDC breaker has faced is high power loss throughout its fault current breaking process. The hybrid HVDC breaker comprises a high voltage bidirectional main HVDC breaker. A significant number of electronic switches need to be connected in a series where anti-parallel diodes are essentially embraced. During fault inception, a number of series solid-state switches and a number of series diodes dramatically increase the power loss of the main breaker. This study, firstly, studies the power loss of the hybrid HVDC breaker and later develops a structure of a full-bridge hybrid breaker (FBHB) to reduce the losses of the current structure both in the normal and fault protection states. In this paper simulations are done based on PSCAD. In addition to the analytical study and simulations, we show that the developed structure substantially decreases the amount of power lost during the normal operation and fault current breaking stage.

Several types of high voltage direct current (HVDC) breakers have been introduced and commercialized. Each of them has advantages and disadvantages. Among them, the hybrid HVDC breaker is highly successful. One of the most important concerns that the hybrid HVDC breaker has faced is high power loss throughout its fault current breaking process. The hybrid HVDC breaker comprises a high voltage bidirectional main HVDC breaker. A significant number of electronic switches need to be connected in a series where anti-parallel diodes are essentially embraced. During fault inception, a number of series solid-state switches and a number of series diodes dramatically increase the power loss of the main breaker. This study, firstly, studies the power loss of the hybrid HVDC breaker and later develops a structure of a full-bridge hybrid breaker (FBHB) to reduce the losses of the current structure both in the normal and fault protection states. In this paper simulations are done based on PSCAD. In addition to the analytical study and simulations, we show that the developed structure substantially decreases the amount of power lost during the normal operation and fault current breaking stage.

The protection of sensitive loads against voltage drop is a concern for the power system. A fast fault current limiter and circuit breaker can be a solution for rapid voltage recovery of sensitive loads. This paper proposes a compound type of current limiter and circuit breaker (CLCB) which can limit fault current and fast break to adjust voltage sags at the protected buses. In addition, it can act as a circuit breaker to open the faulty line. The proposed CLCB is based on a series L-C resonance, which contains a resonant transformer and a series capacitor bank. Moreover, the CLCB includes two anti-parallel power electronic switches (a diode and an IGBT) connected in series with bus couplers. In order to perform an analysis of CLCB performance, the proposed structure was simulated using MATLAB. In addition, an experimental prototype was built, tested, and the experimental results were reported. Comparisons show that experimental results were in fair agreement with the simulation results and confirm CLCB’s ability to act as a fault current limiter and a circuit breaker.

The protection of sensitive loads against voltage drop is a concern for the power system. A fast fault current limiter and circuit breaker can be a solution for rapid voltage recovery of sensitive loads. This paper proposes a compound type of current limiter and circuit breaker (CLCB) which can limit fault current and fast break to adjust voltage sags at the protected buses. In addition, it can act as a circuit breaker to open the faulty line. The proposed CLCB is based on a series L-C resonance, which contains a resonant transformer and a series capacitor bank. Moreover, the CLCB includes two anti-parallel power electronic switches (a diode and an IGBT) connected in series with bus couplers. In order to perform an analysis of CLCB performance, the proposed structure was simulated using MATLAB. In addition, an experimental prototype was built, tested, and the experimental results were reported. Comparisons show that experimental results were in fair agreement with the simulation results and confirm CLCB’s ability to act as a fault current limiter and a circuit breaker.

The protection of sensitive loads against voltage drop is a concern for the power system. A fast fault current limiter and circuit breaker can be a solution for rapid voltage recovery of sensitive loads. This paper proposes a compound type of current limiter and circuit breaker (CLCB) which can limit fault current and fast break to adjust voltage sags at the protected buses. In addition, it can act as a circuit breaker to open the faulty line. The proposed CLCB is based on a series L-C resonance, which contains a resonant transformer and a series capacitor bank. Moreover, the CLCB includes two anti-parallel power electronic switches (a diode and an IGBT) connected in series with bus couplers. In order to perform an analysis of CLCB performance, the proposed structure was simulated using MATLAB. In addition, an experimental prototype was built, tested, and the experimental results were reported. Comparisons show that experimental results were in fair agreement with the simulation results and confirm CLCB’s ability to act as a fault current limiter and a circuit breaker.

The protection of sensitive loads against voltage drop is a concern for the power system. A fast fault current limiter and circuit breaker can be a solution for rapid voltage recovery of sensitive loads. This paper proposes a compound type of current limiter and circuit breaker (CLCB) which can limit fault current and fast break to adjust voltage sags at the protected buses. In addition, it can act as a circuit breaker to open the faulty line. The proposed CLCB is based on a series L-C resonance, which contains a resonant transformer and a series capacitor bank. Moreover, the CLCB includes two anti-parallel power electronic switches (a diode and an IGBT) connected in series with bus couplers. In order to perform an analysis of CLCB performance, the proposed structure was simulated using MATLAB. In addition, an experimental prototype was built, tested, and the experimental results were reported. Comparisons show that experimental results were in fair agreement with the simulation results and confirm CLCB’s ability to act as a fault current limiter and a circuit breaker.

The protection of sensitive loads against voltage drop is a concern for the power system. A fast fault current limiter and circuit breaker can be a solution for rapid voltage recovery of sensitive loads. This paper proposes a compound type of current limiter and circuit breaker (CLCB) which can limit fault current and fast break to adjust voltage sags at the protected buses. In addition, it can act as a circuit breaker to open the faulty line. The proposed CLCB is based on a series L-C resonance, which contains a resonant transformer and a series capacitor bank. Moreover, the CLCB includes two anti-parallel power electronic switches (a diode and an IGBT) connected in series with bus couplers. In order to perform an analysis of CLCB performance, the proposed structure was simulated using MATLAB. In addition, an experimental prototype was built, tested, and the experimental results were reported. Comparisons show that experimental results were in fair agreement with the simulation results and confirm CLCB’s ability to act as a fault current limiter and a circuit breaker.

Glutathione S-transferase enzymes are active in detoxifying a wide number of endogenous and exogenous chemical carcinogens and subsequently, are crucial in protecting the DNA. Several studies show some differences in association of glutathione S-transferase M1, T1 and P1 genetic polymorphisms with the risk of prostate cancer in various populations. The current study was done with Iranian subjects to evaluate the association of the polymorphism of glutathione S-transferase subtypes (T, M and P) and the susceptibility of prostate cancer in Iranian patients as compared to controls. Blood samples were collected from 65 prostate cancer patients and 65 unrelated health individuals as controls from Milad hospital, Tehran, Iran. The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was used to determine the polymorphism of glutathione S-transferase pi (GSTP1) -313 A/G gene, while multiplex PCR method was utilized to detect the glutathione S-transferase teta (GSTT) 1 and glutathione S-transferase mµ (GSTM) 1 null allele. There was no significant association in the -313 G allele (Val) of GSTP1 gene polymorphism and prostate cancer risk (odds ratio 0.61, 95% confidence intervals (CI) 0.08 -4.60, p = 0.627). Moreover, no relationship was found between the polymorphism of GSTT1 (odds ratio 0.66, 95% CI 0.27 -1.62) and GSTM1 (odds ratio 0.54, 95% CI 0.27 -1.08) genes and higher risk of prostate cancer among Iranian subjects (p > 0.05). This study showed that either GSTP1-313 G polymorphism or GSTT1 and GSTM1 genes cannot be predisposing risk factors for prostate cancer among Iranian subjects.

Glutathione S-transferase enzymes are active in detoxifying a wide number of endogenous and exogenous chemical carcinogens and subsequently, are crucial in protecting the DNA. Several studies show some differences in association of glutathione S-transferase M1, T1 and P1 genetic polymorphisms with the risk of prostate cancer in various populations. The current study was done with Iranian subjects to evaluate the association of the polymorphism of glutathione S-transferase subtypes (T, M and P) and the susceptibility of prostate cancer in Iranian patients as compared to controls. Blood samples were collected from 65 prostate cancer patients and 65 unrelated health individuals as controls from Milad hospital, Tehran, Iran. The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was used to determine the polymorphism of glutathione S-transferase pi (GSTP1) -313 A/G gene, while multiplex PCR method was utilized to detect the glutathione S-transferase teta (GSTT) 1 and glutathione S-transferase mµ (GSTM) 1 null allele. There was no significant association in the -313 G allele (Val) of GSTP1 gene polymorphism and prostate cancer risk (odds ratio 0.61, 95% confidence intervals (CI) 0.08 -4.60, p = 0.627). Moreover, no relationship was found between the polymorphism of GSTT1 (odds ratio 0.66, 95% CI 0.27 -1.62) and GSTM1 (odds ratio 0.54, 95% CI 0.27 -1.08) genes and higher risk of prostate cancer among Iranian subjects (p > 0.05). This study showed that either GSTP1-313 G polymorphism or GSTT1 and GSTM1 genes cannot be predisposing risk factors for prostate cancer among Iranian subjects.

Problem statement: Glutathione S-transferase is super family genes that encode enzymes which involve in the detoxification of the cell and protects DNA from damage. Conflicting results was found in several studies in association with GSTT1 and GSTM1 gene polymorphisms and prostate cancer. In this study, we determined the association between the GSTT1 and GSTM1 gene polymorphism and prostate cancer in Iranian subjects as control with control subjects. Approach: Sixty number of sample were collected from both case and control at Milad hospital, Tehran, Iran who were above 40 years of old. Genomic DNA was extracted from blood and the detection of GSTT1 and GSTM1 genotypes was done using multiplex PCR method. Results: The frequency of the null alleles in GSTT1 and GSTM1 was 15 and 41.66% respectively in prostate cancer patients and 21.66 and 56.66% respectively in control subjects. There was no association was found between the polymorphism and prostate cancer among Iranian subjects (p<0.05). Conclusion: This study failed to show an association with GSTT1 and GSTM1 gene polymorphisms and prostate cancer and has no susceptibility to Iranian prostate cancer subjects.

Problem statement: Glutathione S-transferase is super family genes that encode enzymes which involve in the detoxification of the cell and protects DNA from damage. Conflicting results was found in several studies in association with GSTT1 and GSTM1 gene polymorphisms and prostate cancer. In this study, we determined the association between the GSTT1 and GSTM1 gene polymorphism and prostate cancer in Iranian subjects as control with control subjects. Approach: Sixty number of sample were collected from both case and control at Milad hospital, Tehran, Iran who were above 40 years of old. Genomic DNA was extracted from blood and the detection of GSTT1 and GSTM1 genotypes was done using multiplex PCR method. Results: The frequency of the null alleles in GSTT1 and GSTM1 was 15 and 41.66% respectively in prostate cancer patients and 21.66 and 56.66% respectively in control subjects. There was no association was found between the polymorphism and prostate cancer among Iranian subjects (p<0.05). Conclusion: This study failed to show an association with GSTT1 and GSTM1 gene polymorphisms and prostate cancer and has no susceptibility to Iranian prostate cancer subjects.