[Objectives]To determine physicochemical characteristics and antioxidant activity of Ganoderma lucidum polysaccharides(GLP)in different growth stages and culture media.[Methods]Five polysaccharides(GLP1,GLP2,GLP3,GLPW...[Objectives]To determine physicochemical characteristics and antioxidant activity of Ganoderma lucidum polysaccharides(GLP)in different growth stages and culture media.[Methods]Five polysaccharides(GLP1,GLP2,GLP3,GLPW and GLPB)were extracted and purified from the fruiting body of G.lucidum at three growth stages and culture substrates(wood culture and bag culture).The chemical components and antioxidant activity of the five polysaccharides were determined.[Results]GLP1 contained the highest content of neutral sugar(87.65%)and GLP3 had the highest uronic acid content.All the samples mainly comprised glucose,galactose,mannose,xylose and arabose with different ratios.Moreover,their antioxidant activities were investigated on the basis of DPPH radical,ABTS radical,SOD-like activity,and antihaemolytic activity.Results indicated in all three growth stages GLP2 had the greatest antioxidant properties.In addition,the antioxidant activity of GLPW was significantly higher than that of GLPB.[Conclusions]Overall,by comparison,G.lucidum in growth stage two may have potential health benefits,and wood culture may be a superior choice of artificial cultivation due to their abundance of active polysaccharides.展开更多
Background: The widely observed RNA-DNA differences(RDDs) have been found to be due to nucleotide alteration by RNA editing. Canonical RNA editing(i.e., A-to-I and C-to-U editing) mediated by the adenosine deaminases ...Background: The widely observed RNA-DNA differences(RDDs) have been found to be due to nucleotide alteration by RNA editing. Canonical RNA editing(i.e., A-to-I and C-to-U editing) mediated by the adenosine deaminases acting on RNA(ADAR) family and apolipoprotein B mRNA editing catalytic polypeptide-like(APOBEC)family during the transcriptional process is considered common and essential for the development of an individual.To date, an increasing number of RNA editing sites have been reported in human, rodents, and some farm animals;however, genome-wide detection of RNA editing events in sheep has not been reported. The aim of this study was to identify RNA editing events in sheep by comparing the RNA-seq and DNA-seq data from three biological replicates of the kidney and spleen tissues.Results: A total of 607 and 994 common edited sites within the three biological replicates were identified in the ovine kidney and spleen, respectively. Many of the RDDs were specific to an individual. The RNA editing-related genes identified in the present study might be evolved for specific biological functions in sheep, such as structural constituent of the cytoskeleton and microtubule-based processes. Furthermore, the edited sites found in the ovine BLCAP and NEIL1 genes are in line with those in previous reports on the porcine and human homologs, suggesting the existence of evolutionarily conserved RNA editing sites and they may play an important role in the structure and function of genes.Conclusions: Our study is the first to investigate RNA editing events in sheep. We screened out 607 and 994 RNA editing sites in three biological replicates of the ovine kidney and spleen and annotated 164 and 247 genes in the kidney and spleen, respectively. The gene function and conservation analysis of these RNA editing-related genes suggest that RNA editing is associated with important gene function in sheep. The putative functionally important RNA editing sites reported in the present study will help future studies on the relationship between these edited sites and the genetic traits in sheep.展开更多
Partial discharge(PD)signals are an important index to evaluate the operation state of intelligent substations.The correct distinction of PD pulse and interference pulse has become a challenging task.Because of the no...Partial discharge(PD)signals are an important index to evaluate the operation state of intelligent substations.The correct distinction of PD pulse and interference pulse has become a challenging task.Because of the noise and the low signal-to-noise ratio,the stable signals become non-stationary.The selection of a wavelet basis,the selection rule of thresholdλand the design of the threshold function are the key factors affecting the final denoising effect.Therefore,an enhanced ant colony optimisition wavelet(ACOW)algorithm was applied to find the global optimal threshold through the continuous derivative threshold function and the ant colony optimisation(ACO)algo-rithm.At the same time the efficiency of adaptive search calculation,was also significantly improved.The method of the ACOW algorithm was compared with the soft wavelet method,gradient-based wavelet method and the genetic optimisation wavelet(GOW)method.Using these four methods to denoise four typical signals,different mean square errors(MSE),magnitude errors(ME)and time costs were obtained.Interestingly,the results show that the ACOW method can achieve the minimum MSE and has less time cost.It generates significantly smaller waveform distortion than the other three threshold estimation methods.In addition,the high efficiency and good quality of the output signals are beneficial to the diagnosis of local discharge signals in intelligent substations.展开更多
The recent experimental observation of topological magnon insulator states in a superconducting circuit chain marks a breakthrough for topological physics with qubits, in which a dimerized qubit chain has been realize...The recent experimental observation of topological magnon insulator states in a superconducting circuit chain marks a breakthrough for topological physics with qubits, in which a dimerized qubit chain has been realized. Here, we extend such a dimer lattice to superlattice with arbitrary number of qubits in each unit cell in superconducting circuits, which exhibits rich topological properties. Specifically, by considering a quadrimeric superlattice, we show that the topological invariant(winding number) can be effectively characterized by the dynamics of the single-excitation quantum state through time-dependent quantities. Moreover, we explore the appearance and detection of the topological protected edge states in such a multiband qubit system. Finally, we also demonstrate the stable Bloch-like-oscillation of multiple interface states induced by the interference of them. Our proposal can be readily realized in experiment and may pave the way towards the investigation of topological quantum phases and topologically protected quantum information processing.展开更多
The COVID-19 epidemic is raging,and the virus damages the lung,kidney,liver,and cardiovascular system.Medicine for prevention and treatment of COVID-19 requires three properties:being able to efficiently inhibit COVID...The COVID-19 epidemic is raging,and the virus damages the lung,kidney,liver,and cardiovascular system.Medicine for prevention and treatment of COVID-19 requires three properties:being able to efficiently inhibit COVID-19 from infecting cells;being able to quickly repair lung damage;non-toxic.Kyllinga brevifolia Rottb.is found to have the three properties mentioned above and can be used for prevention,treatment and rehabilitation.In terms of rehabilitation of lung,kidney,liver,and cardiovascular diseases,K.brevifolia Rottb.shows remarkable efficacy when combined with other medicinal materials.This is instructive and useful for the rehabilitation of lung,liver,kidney,and cardiovascular damage caused by COVID-19.展开更多
The authors regret<We found an error in Eq.(2)of J.Environ.Sci.,2022,113,345-355(Ncell was obtained from the calculation of ARGs-OAP software,so it doesn’t affect the subsequent results).Eq.(2)is revised as follow...The authors regret<We found an error in Eq.(2)of J.Environ.Sci.,2022,113,345-355(Ncell was obtained from the calculation of ARGs-OAP software,so it doesn’t affect the subsequent results).Eq.(2)is revised as follows(Yang et al.,2016).展开更多
To meet the rapidly growing global demand for aquaculture products,large amounts of antibiotics were used in aquaculture,which might accelerate the evolution of antibiotic-resistant bacteria(ARB)and the propagation of...To meet the rapidly growing global demand for aquaculture products,large amounts of antibiotics were used in aquaculture,which might accelerate the evolution of antibiotic-resistant bacteria(ARB)and the propagation of antibiotic genes(ARGs).In our research,we revealed the ARGs profiles,their co-occurrence with mobile genetic elements(MGEs),and potential hosts in sediments of a crab pond wastewater purification system based on metagenomic analysis.The residual antibiotic seems to increase the propagation of ARGs in the crab pond,but there was no clear relationship between a given antibiotic type and the corresponding resistance genes.The effect of aquaculture on sediment was not as profound as that of other anthropogentic activities,but increased the relative abundance of sulfon-amide resistance gene.A higher abundance of MGEs,especially plasmid,increased the po-tential ARGs dissemination risk in crab and purification ponds.Multidrug and sulfonamide resistance genes had greater potential to transfer because they were more frequently carried by MGEs.The horizontal gene transfer was likely to occur among a variety of microorgan-isms,and various ARGs hosts including Pseudomonas,Acinetobacter,Escherichia,and Klebsiella were identified.Bacterial community influenced the composition of ARG hosts,and Pro-teobacteria was the predominant hosts.Overall,our study provides novel insights into the environmental risk of ARGs in sediments of aquaculture wastewater treatment system.展开更多
Microplastics(MPs)have been widely detected in drinking water sources and tap water,raising the concern of the effectiveness of drinking water treatment plants(DWTPs)in protecting the public from exposure to MPs throu...Microplastics(MPs)have been widely detected in drinking water sources and tap water,raising the concern of the effectiveness of drinking water treatment plants(DWTPs)in protecting the public from exposure to MPs through drinking water.We collected and analyzed the available research articles up to August 2021 on MPs in drinking water treatment(DWT),including laboratory-and full-scale studies.This article summarizes the major MP compositions(materials,sizes,shapes,and concentrations)in drinking water sources,and critically reviews the removal efficiency and impacts of MPs in various drinking water treatment processes.The discussed drinking water treatment processes include coagulation-flocculation(CF),membrane filtration,sand filtration,and granular activated carbon(GAC)filtration.Current DWT processes that are purposed for particle removal are generally effective in reducing MPs in water.Various influential factors to MP removal are discussed,such as coagulant type and dose,MP material,shape and size,and water quality.It is anticipated that better MP removal can be achieved by optimizing the treatment conditions.Moreover,the article framed the major challenges and future research directions on MPs and nanoplastics(NPs)in DWT.展开更多
Dropout and other feature noising schemes have shown promise in controlling over-fitting by artificially corrupting the training data. Though extensive studies have been performed for generalized linear models, little...Dropout and other feature noising schemes have shown promise in controlling over-fitting by artificially corrupting the training data. Though extensive studies have been performed for generalized linear models, little has been done for support vector machines （SVMs）, one of the most successful approaches for supervised learning. This paper presents dropout training for both linear SVMs and the nonlinear extension with latent representation learning. For linear SVMs, to deal with the intractable expectation of the non-smooth hinge loss under corrupting distributions, we develop an iteratively re-weighted least square （IRLS） algorithm by exploring data augmentation techniques. Our algorithm iteratively minimizes the expectation of a re- weighted least square problem, where the re-weights are analytically updated. For nonlinear latent SVMs, we con- sider learning one layer of latent representations in SVMs and extend the data augmentation technique in conjunction with first-order Taylor-expansion to deal with the intractable expected hinge loss and the nonlinearity of latent representa- tions. Finally, we apply the similar data augmentation ideas to develop a new IRLS algorithm for the expected logistic loss under corrupting distributions, and we further develop a non-linear extension of logistic regression by incorporating one layer of latent representations. Our algorithms offer insights on the connection and difference between the hinge loss and logistic loss in dropout training. Empirical results on several real datasets demonstrate the effectiveness of dropout training on significantly boosting the classification accuracy of both linear and nonlinear SVMs.展开更多
A double input-parallel-output-series hybrid switched-capacitor boost(DIPOS-HSCB)converter is proposed which consists of two different kinds of input-parallel-output-series(IPOS)circuits,i.e.,inner IPOS circuit and ou...A double input-parallel-output-series hybrid switched-capacitor boost(DIPOS-HSCB)converter is proposed which consists of two different kinds of input-parallel-output-series(IPOS)circuits,i.e.,inner IPOS circuit and outer IPOS circuit.Two boost modules and one switched-capacitor network build an inner IPOS circuit based IPOS-HSCB converter and two IPOS-HSCB converters develop the outer IPOS circuit based DIPOS-HSCB converter.With the proposed DIPOS-HSCB converter,a high voltage-gain with low component stress and small input current ripple are achieved.Furthermore,an automatic current balancing function for all input inductor currents can be also achieved using a special carrier phase-shifted modulation scheme.A prototype rated at 200 V/120 W has been developed and the maximum efficiency of the proposed DIPOS-HSCB converter is 95% at 120 W.Both steady and dynamic results are presented to validate the effectiveness of the proposed DIPOS-HSCB converter.展开更多
Capacitor voltage imbalance in four-level(4L)neutral-point clamped(NPC)converters is a direct factor hindering their application.In particular,when they are applied in motor drives,space vector pulse-width modulation(...Capacitor voltage imbalance in four-level(4L)neutral-point clamped(NPC)converters is a direct factor hindering their application.In particular,when they are applied in motor drives,space vector pulse-width modulation(SVPWM)is a more popular scheme,but conventional 4L SVPWM cannot achieve the voltage balancing control of DC-link capacitors,is complex to implement,and requires costly computation.A hybrid modulation method with capacitor voltage-balancing control for 4L NPC converters is proposed.The proposed method is achieved using three-level(3L)SVPWM and two-level(2L)carrier-based pulse-width modulation(CPWM)based on the concept of"4L=3L+2L".Thus,it can be easily implemented on a digital chip because the modulation process is nearly identical to that of 3L SVPWM without the more cumbersome 4L SVPWM algorithm.Meanwhile,any proven optimization scheme of 3L SVPWM can be directly applied to the proposed method to further improve performance.Simulation and experimental results for a 4L active NPC converter demonstrate the effectiveness of the proposed method.展开更多
基金Supported by the New Variety Breeding Project of Science Technology Department of Zhejiang Province(2021C02073)Agriculture,Rural Areas and Farmers and Nine-Party Project of Zhejiang Province(2022SNJF047)。
文摘[Objectives]To determine physicochemical characteristics and antioxidant activity of Ganoderma lucidum polysaccharides(GLP)in different growth stages and culture media.[Methods]Five polysaccharides(GLP1,GLP2,GLP3,GLPW and GLPB)were extracted and purified from the fruiting body of G.lucidum at three growth stages and culture substrates(wood culture and bag culture).The chemical components and antioxidant activity of the five polysaccharides were determined.[Results]GLP1 contained the highest content of neutral sugar(87.65%)and GLP3 had the highest uronic acid content.All the samples mainly comprised glucose,galactose,mannose,xylose and arabose with different ratios.Moreover,their antioxidant activities were investigated on the basis of DPPH radical,ABTS radical,SOD-like activity,and antihaemolytic activity.Results indicated in all three growth stages GLP2 had the greatest antioxidant properties.In addition,the antioxidant activity of GLPW was significantly higher than that of GLPB.[Conclusions]Overall,by comparison,G.lucidum in growth stage two may have potential health benefits,and wood culture may be a superior choice of artificial cultivation due to their abundance of active polysaccharides.
基金funded by the National Nature Science Foundation of China(U1136605)Ningxia Agricultural Breeding Program(NXNYYZ20150103)Program for Changjiang Scholar and Innovation Research Team in University(IRT1191)
文摘Background: The widely observed RNA-DNA differences(RDDs) have been found to be due to nucleotide alteration by RNA editing. Canonical RNA editing(i.e., A-to-I and C-to-U editing) mediated by the adenosine deaminases acting on RNA(ADAR) family and apolipoprotein B mRNA editing catalytic polypeptide-like(APOBEC)family during the transcriptional process is considered common and essential for the development of an individual.To date, an increasing number of RNA editing sites have been reported in human, rodents, and some farm animals;however, genome-wide detection of RNA editing events in sheep has not been reported. The aim of this study was to identify RNA editing events in sheep by comparing the RNA-seq and DNA-seq data from three biological replicates of the kidney and spleen tissues.Results: A total of 607 and 994 common edited sites within the three biological replicates were identified in the ovine kidney and spleen, respectively. Many of the RDDs were specific to an individual. The RNA editing-related genes identified in the present study might be evolved for specific biological functions in sheep, such as structural constituent of the cytoskeleton and microtubule-based processes. Furthermore, the edited sites found in the ovine BLCAP and NEIL1 genes are in line with those in previous reports on the porcine and human homologs, suggesting the existence of evolutionarily conserved RNA editing sites and they may play an important role in the structure and function of genes.Conclusions: Our study is the first to investigate RNA editing events in sheep. We screened out 607 and 994 RNA editing sites in three biological replicates of the ovine kidney and spleen and annotated 164 and 247 genes in the kidney and spleen, respectively. The gene function and conservation analysis of these RNA editing-related genes suggest that RNA editing is associated with important gene function in sheep. The putative functionally important RNA editing sites reported in the present study will help future studies on the relationship between these edited sites and the genetic traits in sheep.
基金Program of Chongqing Banan District,Grant/Award Number:2020QC407Chongqing Municipal Education Commission,Grant/Award Number:KJQN202001146+1 种基金National Key Research and Development Program,Grant/Award Number:2018YFB2100100Joint Funds of the National Natural Science Foundation of China,Grant/Award Number:U1866603。
文摘Partial discharge(PD)signals are an important index to evaluate the operation state of intelligent substations.The correct distinction of PD pulse and interference pulse has become a challenging task.Because of the noise and the low signal-to-noise ratio,the stable signals become non-stationary.The selection of a wavelet basis,the selection rule of thresholdλand the design of the threshold function are the key factors affecting the final denoising effect.Therefore,an enhanced ant colony optimisition wavelet(ACOW)algorithm was applied to find the global optimal threshold through the continuous derivative threshold function and the ant colony optimisation(ACO)algo-rithm.At the same time the efficiency of adaptive search calculation,was also significantly improved.The method of the ACOW algorithm was compared with the soft wavelet method,gradient-based wavelet method and the genetic optimisation wavelet(GOW)method.Using these four methods to denoise four typical signals,different mean square errors(MSE),magnitude errors(ME)and time costs were obtained.Interestingly,the results show that the ACOW method can achieve the minimum MSE and has less time cost.It generates significantly smaller waveform distortion than the other three threshold estimation methods.In addition,the high efficiency and good quality of the output signals are beneficial to the diagnosis of local discharge signals in intelligent substations.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.12034012,12074232,12125406,and 11804204)1331KSC。
文摘The recent experimental observation of topological magnon insulator states in a superconducting circuit chain marks a breakthrough for topological physics with qubits, in which a dimerized qubit chain has been realized. Here, we extend such a dimer lattice to superlattice with arbitrary number of qubits in each unit cell in superconducting circuits, which exhibits rich topological properties. Specifically, by considering a quadrimeric superlattice, we show that the topological invariant(winding number) can be effectively characterized by the dynamics of the single-excitation quantum state through time-dependent quantities. Moreover, we explore the appearance and detection of the topological protected edge states in such a multiband qubit system. Finally, we also demonstrate the stable Bloch-like-oscillation of multiple interface states induced by the interference of them. Our proposal can be readily realized in experiment and may pave the way towards the investigation of topological quantum phases and topologically protected quantum information processing.
基金2020 COVID-19 Infection Emergency Prevention and Control Technology Special Project of Suzhou Science and Technology Bureau(XG32)Project of Chongqing Municipal Education Commission(yjg143075).
文摘The COVID-19 epidemic is raging,and the virus damages the lung,kidney,liver,and cardiovascular system.Medicine for prevention and treatment of COVID-19 requires three properties:being able to efficiently inhibit COVID-19 from infecting cells;being able to quickly repair lung damage;non-toxic.Kyllinga brevifolia Rottb.is found to have the three properties mentioned above and can be used for prevention,treatment and rehabilitation.In terms of rehabilitation of lung,kidney,liver,and cardiovascular diseases,K.brevifolia Rottb.shows remarkable efficacy when combined with other medicinal materials.This is instructive and useful for the rehabilitation of lung,liver,kidney,and cardiovascular damage caused by COVID-19.
文摘The authors regret<We found an error in Eq.(2)of J.Environ.Sci.,2022,113,345-355(Ncell was obtained from the calculation of ARGs-OAP software,so it doesn’t affect the subsequent results).Eq.(2)is revised as follows(Yang et al.,2016).
基金This work was financially supported by the National Natural Science Foundation of China(No.51778006)the High-performance Computing Platform of Peking University。
文摘To meet the rapidly growing global demand for aquaculture products,large amounts of antibiotics were used in aquaculture,which might accelerate the evolution of antibiotic-resistant bacteria(ARB)and the propagation of antibiotic genes(ARGs).In our research,we revealed the ARGs profiles,their co-occurrence with mobile genetic elements(MGEs),and potential hosts in sediments of a crab pond wastewater purification system based on metagenomic analysis.The residual antibiotic seems to increase the propagation of ARGs in the crab pond,but there was no clear relationship between a given antibiotic type and the corresponding resistance genes.The effect of aquaculture on sediment was not as profound as that of other anthropogentic activities,but increased the relative abundance of sulfon-amide resistance gene.A higher abundance of MGEs,especially plasmid,increased the po-tential ARGs dissemination risk in crab and purification ponds.Multidrug and sulfonamide resistance genes had greater potential to transfer because they were more frequently carried by MGEs.The horizontal gene transfer was likely to occur among a variety of microorgan-isms,and various ARGs hosts including Pseudomonas,Acinetobacter,Escherichia,and Klebsiella were identified.Bacterial community influenced the composition of ARG hosts,and Pro-teobacteria was the predominant hosts.Overall,our study provides novel insights into the environmental risk of ARGs in sediments of aquaculture wastewater treatment system.
文摘Microplastics(MPs)have been widely detected in drinking water sources and tap water,raising the concern of the effectiveness of drinking water treatment plants(DWTPs)in protecting the public from exposure to MPs through drinking water.We collected and analyzed the available research articles up to August 2021 on MPs in drinking water treatment(DWT),including laboratory-and full-scale studies.This article summarizes the major MP compositions(materials,sizes,shapes,and concentrations)in drinking water sources,and critically reviews the removal efficiency and impacts of MPs in various drinking water treatment processes.The discussed drinking water treatment processes include coagulation-flocculation(CF),membrane filtration,sand filtration,and granular activated carbon(GAC)filtration.Current DWT processes that are purposed for particle removal are generally effective in reducing MPs in water.Various influential factors to MP removal are discussed,such as coagulant type and dose,MP material,shape and size,and water quality.It is anticipated that better MP removal can be achieved by optimizing the treatment conditions.Moreover,the article framed the major challenges and future research directions on MPs and nanoplastics(NPs)in DWT.
文摘Dropout and other feature noising schemes have shown promise in controlling over-fitting by artificially corrupting the training data. Though extensive studies have been performed for generalized linear models, little has been done for support vector machines （SVMs）, one of the most successful approaches for supervised learning. This paper presents dropout training for both linear SVMs and the nonlinear extension with latent representation learning. For linear SVMs, to deal with the intractable expectation of the non-smooth hinge loss under corrupting distributions, we develop an iteratively re-weighted least square （IRLS） algorithm by exploring data augmentation techniques. Our algorithm iteratively minimizes the expectation of a re- weighted least square problem, where the re-weights are analytically updated. For nonlinear latent SVMs, we con- sider learning one layer of latent representations in SVMs and extend the data augmentation technique in conjunction with first-order Taylor-expansion to deal with the intractable expected hinge loss and the nonlinearity of latent representa- tions. Finally, we apply the similar data augmentation ideas to develop a new IRLS algorithm for the expected logistic loss under corrupting distributions, and we further develop a non-linear extension of logistic regression by incorporating one layer of latent representations. Our algorithms offer insights on the connection and difference between the hinge loss and logistic loss in dropout training. Empirical results on several real datasets demonstrate the effectiveness of dropout training on significantly boosting the classification accuracy of both linear and nonlinear SVMs.
文摘A double input-parallel-output-series hybrid switched-capacitor boost(DIPOS-HSCB)converter is proposed which consists of two different kinds of input-parallel-output-series(IPOS)circuits,i.e.,inner IPOS circuit and outer IPOS circuit.Two boost modules and one switched-capacitor network build an inner IPOS circuit based IPOS-HSCB converter and two IPOS-HSCB converters develop the outer IPOS circuit based DIPOS-HSCB converter.With the proposed DIPOS-HSCB converter,a high voltage-gain with low component stress and small input current ripple are achieved.Furthermore,an automatic current balancing function for all input inductor currents can be also achieved using a special carrier phase-shifted modulation scheme.A prototype rated at 200 V/120 W has been developed and the maximum efficiency of the proposed DIPOS-HSCB converter is 95% at 120 W.Both steady and dynamic results are presented to validate the effectiveness of the proposed DIPOS-HSCB converter.
基金Supported in part by the Guangdong Innovative Program on New Power System Technology under Grant 1688483408285in part by the National Natural Science Foundation of China under Grant 52207221in part by Wuhan Science and Technology Project under Grant 2023010201010071.
文摘Capacitor voltage imbalance in four-level(4L)neutral-point clamped(NPC)converters is a direct factor hindering their application.In particular,when they are applied in motor drives,space vector pulse-width modulation(SVPWM)is a more popular scheme,but conventional 4L SVPWM cannot achieve the voltage balancing control of DC-link capacitors,is complex to implement,and requires costly computation.A hybrid modulation method with capacitor voltage-balancing control for 4L NPC converters is proposed.The proposed method is achieved using three-level(3L)SVPWM and two-level(2L)carrier-based pulse-width modulation(CPWM)based on the concept of"4L=3L+2L".Thus,it can be easily implemented on a digital chip because the modulation process is nearly identical to that of 3L SVPWM without the more cumbersome 4L SVPWM algorithm.Meanwhile,any proven optimization scheme of 3L SVPWM can be directly applied to the proposed method to further improve performance.Simulation and experimental results for a 4L active NPC converter demonstrate the effectiveness of the proposed method.
