This paper presents a nonlinear control approach to variable speed wind turbine(VSWT)with a wind speed estimator.The dynamics of the wind turbine(WT)is derived from single mass model.In this work,a modified Newton Rap...This paper presents a nonlinear control approach to variable speed wind turbine(VSWT)with a wind speed estimator.The dynamics of the wind turbine(WT)is derived from single mass model.In this work,a modified Newton Raphson estimator has been considered for exact estimation of effective wind speed.The main objective of this work is to extract maximum energy from the wind at below rated wind speed while reducing drive train oscillation.In order to achieve the above objectives,VSWT should operate close to the optimal power coefficient.The generator torque is considered as the control input to achieve maximum energy capture.From the literature,it is clear that existing linear and nonlinear control techniques suffer from poor tracking of WT dynamics,increased power loss and complex control law.In addition,they are not robust with respect to input disturbances.In order to overcome the above drawbacks,adaptive fuzzy integral sliding mode control(AFISMC)is proposed for VSWT control.The proposed controller is tested with different types of disturbances and compared with other nonlinear controllers such as sliding mode control and integral sliding mode control.The result shows the better performance of AFISMC and its robustness to input disturbances.In this paper,the discontinuity in integral sliding mode controller is smoothed by using hyperbolic tangent function,and the sliding gain is adapted using a fuzzy technique which makes the controller more robust.展开更多
Due to their extraordinary durability and thermal stability,Epoxy Resin Thermosets(ERTs)are essential in various industries.However,their poor recyclability leads to unacceptable environmental pollution.In this study,...Due to their extraordinary durability and thermal stability,Epoxy Resin Thermosets(ERTs)are essential in various industries.However,their poor recyclability leads to unacceptable environmental pollution.In this study,Wu et al.successfully synthesized a completely bio-based ERT using lignocellulose-derived building blocks which exhibit outstanding thermal and mechanical properties.Remarkably,these bio-materials degrade via methanolysis without the need of any catalyst,presenting a smart and cost-effective recycling strategy.Furthermore,this approach could be employed for fabricating reusable composites comprising glass fiber and plant fiber,thereby expanding its applications in sustainable transportation,coatings,paints or biomedical devices.展开更多
To optimize the energy capture from the wind,wind turbine(WT)should operate at variable speed.Based on the wind speed,the operating regions of the WT are divided into two parts:below and above the rated wind speed.The...To optimize the energy capture from the wind,wind turbine(WT)should operate at variable speed.Based on the wind speed,the operating regions of the WT are divided into two parts:below and above the rated wind speed.The main aim at below rated wind speed is to maximize the energy capture from the wind with reduced oscillation on the drive train.At above rated wind speed,the aim is to maintain the rated power by using pitch control.This paper presents the control of WT at below rated wind speed by using backstepping sliding mode control(BSMC).In BSMC,generator torque is considered as the control input that depends on the optimal rotor speed.Usually,this optimal rotor speed is derived from effective wind speed.In this paper,effective wind speed is estimated from aerodynamic torque and rotor speed by using the modified Newton Rapshon(MNR)algorithm.Initially,a conventional sliding mode controller(SMC)is applied to the WT,but the performance of the controller was found to be less robust with respect to disturbances.Generally,WT external disturbance is not predictable.To overcome the above drawback,BSMC is proposed and both the controllers are tested with mathematical model and finally validated with the fatigue,aerodynamics,structures,and turbulence(FAST)WT simulator in the presence of disturbances.From the results,it is concluded that the proposed BSMC is more robust than conventional SMC in the presence of disturbances.展开更多
The present study revealed proliferation of macro-algae modifying coral reef ecosystems in a different manner due to diseases and sedimentations in the Mandapam group of islands in the Gulf of Mannar. Benthic surveys ...The present study revealed proliferation of macro-algae modifying coral reef ecosystems in a different manner due to diseases and sedimentations in the Mandapam group of islands in the Gulf of Mannar. Benthic surveys were conducted with major attack of seven coral reefs diseases with high sedimentation rate, nine species of fleshy macro-algae(Turbinaria ornata, Turbinaria conaides, Caulerpa scalpelliformis, Caulerpa racemosa, Kappaphycus alvarezii, Padina gymnosphora, Sargassum wightii, Ulva reticulata and Calurpa lentillifera) proliferation against major corals life forms(Acropora branching, Acropora digitate, Acropora tabulate, coral massive, coral submassive, coral foliose and coral encrusting). The results confirm that diseased corals most favor to macro-algae growth(15.27%) rather than the sedimentation covered corals(8.24 %). In the degradation of coral life forms, massive corals were more highly damaged(7.05%) than any other forms. Within a short period of time(May to September), coral coverage shrank to 17.4% from 21.9%, macro-algae increased 23.51% and the average sedimentation rate attained 77.52 mg cm^(-2) d^(-1) with persisting coral reef diseases of 17.59%. The Pearson correlation showed that the coral cover decreased with increasing macro-algae growth, which was statistically significant(r =-0.774, n = 100, P < 0.0005). The proliferation of the various macro-algae C. scalpellifrmis, T. ornata, C. racemosa, T. conaides, U. reticulata, S. wightii, K. alvarezii, P. gymnosphora and C. lentillifera increased with percentages of 6.0, 5.8, 5.7, 4.9, 4.2, 3.7, 2.7 and 1.9, respectively. If this trend continues, the next generation of new recruit corals will undoubtedly lead to a phase shift in Gulf of Mannar corals.展开更多
The wireless sensor network (WSN) is one of the budding exploring areas and fast rising fields in wireless communications. The sensor nodes in the network are generally small-size, low-cost, low-power and multi-functi...The wireless sensor network (WSN) is one of the budding exploring areas and fast rising fields in wireless communications. The sensor nodes in the network are generally small-size, low-cost, low-power and multi-function capabilities. Wireless sensor networks (WSNs) are used for various applications;since numerous sensor nodes are usually deployed on remote and inaccessible places, the employment and preservation should be easy and scalable. Sensor nodes in the field being run out of energy quickly has been an issue and many energy efficient routing protocols have been proposed to solve this problem and preserve the long life of the network. This paper work proposes a hierarchical based node activation routing technique which shows energy efficiency. This technique selects cluster head with highest residual energy in each communication round of transmission to the base station from the cluster heads. Hierarchical based node activation routing technique with different levels of hierarchy simulation results prolongs the lifetime of the network compared to other clustering schemes and communication rounds of simulation increase significantly.展开更多
Dear Editor,The promptness and continuous expansion of the coronavirus disease 2019(COVID-19)pandemic,elicited by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)and its variants,has presented an unpreceden...Dear Editor,The promptness and continuous expansion of the coronavirus disease 2019(COVID-19)pandemic,elicited by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)and its variants,has presented an unprecedented impact on human health(WHO Coronavirus(COVID-19)Dashboard,2021).Although vaccination has attenuated the severe symptoms,there is no specific antiviral medication available for preventing the viral spread(Drayman et al.,2021).展开更多
This study reports a strain of Trichoderma harzianum CCTCC-SBW0162 with potential to enhance biocontrol activity against gray mold pathogen, Botrytis cinerea, and with a pivotal role in tomato(Solanum esculentum) plan...This study reports a strain of Trichoderma harzianum CCTCC-SBW0162 with potential to enhance biocontrol activity against gray mold pathogen, Botrytis cinerea, and with a pivotal role in tomato(Solanum esculentum) plant growth enhancement. A total of 254 Trichoderma isolates were screened by in vitro antagonistic assay. Of these, 10 were selected for greenhouse experiments based on their greater inhibition of B. cinerea.The in vitro antagonistic assay and greenhouse experiments indicated that T. harzianum CCTCC-SBW0162 gave the highest inhibition rate(90.6%) and disease reduction(80.7%). Also, to study the possible mechanism associated with antifungal activity of CCTCC-SBW0162 against B. cinerea, molecular docking was used to assess the interactions between CCTCC-SBW0162-derived metabolites, and pathogencity and virulence related proteins of B. cinerea. The molecular docking results indicated that the combination of harzianopyridone,harzianolide and anthraquinone C derived from CCTCCSBW0162 could synergistically improve antifungal activity against B. cinerea through the inhibition/modification of pathogenicity and virulence related proteins.However, this computerized modeling work emphasized the need for further study in the laboratory to confirm the effect T. harzianum-derived metabolites against the proteins of B. cinerea and their interactions.展开更多
Phytomediated synthesis of metal oxide nanoparticles has become a key research area in nanotechnology due to its wide applicability in various biomedical fields. The present work explores the biosynthesis of zinc oxid...Phytomediated synthesis of metal oxide nanoparticles has become a key research area in nanotechnology due to its wide applicability in various biomedical fields. The present work explores the biosynthesis of zinc oxide nanoparticles（ZnO-NPs） using Leucaena leucocephala leaf extract. The synthesised ZnO-NPs were characterised by ultraviolet-visible（UV-Vis） spectroscopy, scanning electron microscopy（SEM）, energydispersive X-ray spectroscopy（EDX）, Fourier transform infrared spectroscopy（FTIR）, X-ray diffraction（XRD）,transmission electron microscopy（TEM） and selected area electron diffraction（SAED） studies. Biosynthesised ZnONPs are found to have wurtzite hexagonal structure with particles distributed in the range of 50-200 nm as confirmed by TEM studies. The anticancer activity of ZnONPs against MCF-7（breast cancer） and PC-3（human prostate cancer） cell lines was evaluated using 3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide（MTT） assay. From the assay, biosynthesised ZnO-NPs have better cytotoxic activity on PC-3 cell lines than MCF-7 cell lines. The in vitro cytotoxicity studies of biosynthesised ZnO-NPs against Dalton lymphoma ascites（DLA）cells reveal better antitumor activity of 92% inhibition with concentration of 200 μg·ml-1 of ZnO-NPs,and as the concentration increases, the anticancer efficiency as well increases, and also, it has excellent photocatalytic activity to degrade crystal violet dye in aqueous solution after irradiation of 90 min. The result suggests that the green synthesis of ZnO-NPs could be easily recovered and reused several times without any significant loss of the catalytic activity. The advantage of this technique lies in its low cost, easily climb able and non-use of toxic agents.展开更多
Ezrin,a membrane–cytoskeleton linker protein,plays an essential role in cell polarity establishment,cell migration,and division.Recent studies show that ezrin phosphorylation regulates breast cancer metastasis by pro...Ezrin,a membrane–cytoskeleton linker protein,plays an essential role in cell polarity establishment,cell migration,and division.Recent studies show that ezrin phosphorylation regulates breast cancer metastasis by promoting cancer cell survivor and promotes intrahepatic metastasis via cell migration.However,it was less characterized whether there are additional post-translational modifications and/or post-translational crosstalks on ezrin underlying context-dependent breast cancer cell migration and invasion.Here we show that ezrin is acetylated by p300/CBP-associated factor(PCAF)in breast cancer cells in response to CCL18 stimulation.Ezrin physically interacts with PCAF and is a cognate substrate of PCAF.The acetylation site of ezrin was mapped by mass spectrometric analyses,and dynamic acetylation of ezrin is essential for CCL18-induced breast cancer cell migration and invasion.Mechanistically,the acetylation reduced the lipid-binding activity of ezrin to ensure a robust and dynamic cycling between the plasma membrane and cytosol in response to CCL18 stimulation.Biochemical analyses show that ezrin acetylation prevents the phosphorylation of Thr567.Using atomic force microscopic measurements,our study revealed that acetylation of ezrin induced its unfolding into a dominant structure,which prevents ezrin phosphorylation at Thr567.Thus,these results present a previously undefined mechanism by which CCL18-elicited crosstalks between the acetylation and phosphorylation on ezrin control breast cancer cell migration and invasion.This suggests that targeting PCAF signaling could be a potential therapeutic strategy for combating hyperactive ezrin-driven cancer progression.展开更多
Seasonal and inter-annual variability of hydrological parameters and its impact on chlorophyll distribution was studied from January 2009 to December 2011 at four coastal stations along the southwest Bay of Bengal. St...Seasonal and inter-annual variability of hydrological parameters and its impact on chlorophyll distribution was studied from January 2009 to December 2011 at four coastal stations along the southwest Bay of Bengal. Statistical analysis （principal component analysis （PCA）, two-way analysis of variance （ANOVA） and correlation analysis） showed the significant impact of hydrological parameters on chlorophyll distribution in the study area. The ranges of different parameters recorded were 23.8-33.8℃ （SST）, 4.00-36.00 （salinity）, 7.0-9.2 （pH）, 4.41-8.32 mg/L （dissolved oxygen）, 0.04-2.45 μmol/L （nitrite）, 0.33-16.10 μmol/L （nitrate）, 0.02-2.51 μmol/L （ammonia）, 0.04-3.32 μmol/L （inorganic phosphate）, 10.09-85.28 μmol/L （reactive silicate） and 0.04-13.8 μg/L （chlorophyll）. PCA analysis carried out for different seasons found variations in the relationship between physico-chemical parameters and chlorophyll in which nitrate and chlorophyll were positively loaded at PC1 （principal component 1） during spring inter-monsoon and at PC2 （principal component 2） during other seasons. Likewise correlation analysis also showed significant positive relationship between chlorophyll and nutrients especially with nitrate （~0.734）. Distribution of hydrobiological parameters between stations and distances was significantly varying as evidenced from the ANOVA results. The study found that the spatial and temporal distribution of chlorophyll was highly dependent on the availability of nutrients especially, nitrate in the southwest Bay of Bengal coastal waters.展开更多
The total benthic macrofauna consisting of 62 species in 5 groups,viz. crustaceans(18),gastropods(17),bivalves(16),polychaetes(9) and fishes(2),was recorded in western Kachchh mangroves near Gujarat. The population de...The total benthic macrofauna consisting of 62 species in 5 groups,viz. crustaceans(18),gastropods(17),bivalves(16),polychaetes(9) and fishes(2),was recorded in western Kachchh mangroves near Gujarat. The population densities of benthic macro-fauna ranged from 424 to 2393 ind.m-2,the diversity ranged from 1.84 to 2.45 bits ind.-1,the richness varied between 0.82 and 0.98,and the evenness varied between 0.64 and 0.81. Two maximum diversity values were recorded during winter and summer. The salin-ity ranged from 34 to 44,temperature varied between 17 and 37 ℃,and the acidity ranged from 7 to 8.9.展开更多
Stable transmission of genetic information during cell division requires faithful mitotic spindle assembly and chromosome segregation.In eukaryotic cells,nuclear envelope breakdown(NEBD)is required for proper chromoso...Stable transmission of genetic information during cell division requires faithful mitotic spindle assembly and chromosome segregation.In eukaryotic cells,nuclear envelope breakdown(NEBD)is required for proper chromosome segregation.Although a list of mitotic kinases has been implicated in NEBD,how they coordinate their activity to dissolve the nuclear envelope and protein machinery such as nuclear pore complexes was unclear.Here,we identified a regulatory mechanism in which Nup62 is acetylated by TIP60 in human cell division.Nup62 is a novel substrate of TIP60,and the acetylation of Lys432 by TIP60 dissolves nucleoporin Nup62-Nup58-Nup54 complex during entry into mitosis.Importantly,this acetylation-elicited remodeling of nucleoporin complex promotes the distribution of Nup62 to the mitotic spindle,which is indispensable for orchestrating correct spindle orientation.Moreover,suppression of Nup62 perturbs accurate chromosome segregation during mitosis.These results establish a previously uncharacterized regulatory mechanism in which TIP60-elicited nucleoporin dynamics promotes chromosome segregation in mitosis.展开更多
Electrochemical energy storage devices(EESs)play a crucial role for the construction of sustainable energy storage system from the point of generation to the end user due to the intermittent nature of renewable source...Electrochemical energy storage devices(EESs)play a crucial role for the construction of sustainable energy storage system from the point of generation to the end user due to the intermittent nature of renewable sources.Additionally,to meet the demand for next-generation electronic applications,optimizing the energy and power densities of EESs with long cycle life is the crucial factor.Great e orts have been devoted towards the search for new materials,to augment the overall performance of the EESs.Although there are a lot of ongoing researches in this field,the performance does not meet up to the level of commercialization.A further understanding of the charge storage mechanism and development of new electrode materials are highly required.The present review explains the overview of recent progress in supercapattery devices with reference to their various aspects.The di erent charge storage mechanisms and the multiple factors involved in the performance of the supercapattery are described in detail.Moreover,recent advancements in this supercapattery research and its electrochemical performances are reviewed.Finally,the challenges and possible future developments in this field are summarized.展开更多
This work focuses on the fuzzy controller for the proposed three-phase interleaved Step-up converter(ISC).The fuzzy controller for the proposed ISC converters for electric vehicles has been discussed in detail.The pro...This work focuses on the fuzzy controller for the proposed three-phase interleaved Step-up converter(ISC).The fuzzy controller for the proposed ISC converters for electric vehicles has been discussed in detail.The proposed ISC direct current(DC-DC)converter could also be used in automobiles,satellites,industries,and propulsion.To enhance voltage gain,the proposed ISC Converter combines boost converter and interleaved converter(IC).This design also reduces the number of switches.As a result,ISC converter switching losses are reduced.The proposed ISC Converter topology can produce a 143 V output voltage and 1 kW of power.Due to the high voltage gain of this converter design,it is suitable for medium and high-power systems.The proposed ISC Converter topology is simulated in MATLAB/Simulink.The simulated output displays a high output voltage.But the output voltage contains maximum ripples.Fuzzy proposes an ISC Converter which makes closed loop responsiveness and reduces the output voltage ripple.The proposed ISC converter has the lowest ripple output voltage,which is less than 2%,because the duty cycle is regulated using the fuzzy logic controller.It offers high voltage gain,minimal ripple,and low switching loss.The performance of the proposed converter is compared to that of the fuzzy and Pro-portional Integral(PI)controllers implemented in MATLAB.展开更多
This work quantified the total carbon and 12 other sediment characteristics at 10 soil depths, in planted and or natural mangrove forests in comparison with non-vegetated soil for four seasons of the year 2009-2010 in...This work quantified the total carbon and 12 other sediment characteristics at 10 soil depths, in planted and or natural mangrove forests in comparison with non-vegetated soil for four seasons of the year 2009-2010 in the Vellar-Coleroon estuarine complex, India. The sedi- ment characteristics varied significantly between mangrove-vegetated and non-vegetated habitats or seasons of analysis, but not between soil depths. The mangrove sediments were rich in total carbon and total or- ganic carbon as compared to non-mangrove sediments （p 〈0.01）. Total carbon was 98.2% higher in mature mangroves and 41.8% in planted mangroves than that in non-mangrove soil. Total organic carbon was as much as 2.5 times greater in mature mangroves and 2 times greater in planted mangroves than that in unvegetated soil. Carbon contents also varied many fold by season. Total carbon content was 8.6 times greater during pre-monsoon, 4.1 times greater during post-monsoon and 2.5 times greater during monsoon than during summer （P〈0.01 in all cases）. Similarly, total organic carbon was 5.9 times greater during pre-monsoon, 3.1 times greater during post-monsoon and 69% greater during monsoon than during summer. In general, higher levels of sediment carbon were recorded during pre and post-monsoon seasons than during other seasons. Total carbon concentration was correlated negatively to temperature, sand and phosphorus （P 〈0.01）; positively correlated with redox potential, silt, clay, C/N ratio, potassium （P 〈0.01） and nitrogen （P〈0.05）; but not correlated with soil depth, pH or salinity. This work revealed that the carbon burial was rapid at the annual rate of 2.8% for total carbon, and 6.7% for total organic carbon in mangrove-planted sediment. Cleating of mangroves can result in significantly and rapidly reduced carbon stores.Our study highlights the importance of natural and plantation mangrove stands for conserving sediment carbon in the tropical coastal domain.展开更多
The finfish and shellfish resources were assessed quantitatively and qualitatively in regard to their abundance in creek waters at three sites within a period of two years, fi＇om January 1999 to December 2000, in the...The finfish and shellfish resources were assessed quantitatively and qualitatively in regard to their abundance in creek waters at three sites within a period of two years, fi＇om January 1999 to December 2000, in the western mangrove areas of Kachchh. The catch rate varied from 0.69 to 6.99kg·h^-1. It was low during monsoon （July to October）, which could be due to the freshwater-flow-induced salinity reduction in all the sites. Among 38 species recorded, 5 were shellfish and 33 were finfish. The spawning period of fishes was found to be during summer and early monsoon period （May to August）. Surface water temperatures varied from 17℃ to 37 ℃. Salinity values varied from 34 to 44 and the pH ranged between 7 and 8.9. Variation in dissolved oxygen content was from 3.42 to 5.85 mL L^-1. The high fishery densities in these semi arid mangrove creek areas were recorded during monsoon and early winter season.展开更多
The exploration of polymer electrolyte in the field of dye sensitized solar cell(DSSC) can contribute to increase the invention of renewable energy applications. In the present work, the influence of imidazole on the ...The exploration of polymer electrolyte in the field of dye sensitized solar cell(DSSC) can contribute to increase the invention of renewable energy applications. In the present work, the influence of imidazole on the poly(vinylidene fluoride)(PVDF)–poly(methyl methacrylate)(PMMA)–Ethylene carbonate(EC)–KI–I2 polymer blend electrolytes has been evaluated. The different weight percentages of imidazole added into polymer blend electrolytes have been prepared by solution casting. The prepared films were characterized by Fourier transform infrared spectroscopy(FTIR), X-ray diffraction(XRD), thermogravimetric analysis(TGA), UV–visible spectra, photoluminescence spectra and impedance spectroscopy. The surface roughness texture of the film was analyzed by atomic force microscopy(AFM). The ionic conductivity of the optimized polymer blend electrolyte was determined by impedance measurement, which is 1.95 × 10-3 S·cm-1 at room temperature. The polymer electrolyte containing 40 wt% of imidazole content exhibits the highest photo-conversion efficiency of 3.04%under the illumination of 100 m W·cm-2. Moreover, a considerable enhancement in the stability of the DSSC device was demonstrated.展开更多
We scrutinize the problem of robust H∞control for a class of Markovian jump uncertain systems with interval timevarying and distributed delays. The Markovian jumping parameters are modeled as a continuous-time finite...We scrutinize the problem of robust H∞control for a class of Markovian jump uncertain systems with interval timevarying and distributed delays. The Markovian jumping parameters are modeled as a continuous-time finite-state Markov chain. The main aim is to design a delay-dependent robust H∞control synthesis which ensures the mean-square asymptotic stability of the equilibrium point. By constructing a suitable Lyapunov–Krasovskii functional（LKF）, sufficient conditions for delay-dependent robust H∞control criteria are obtained in terms of linear matrix inequalities（LMIs）. The advantage of the proposed method is illustrated by numerical examples. The results are also compared with the existing results to show the less conservativeness.展开更多
Core sediments from the Muthupettai mangroves on the southeast coast of India were analyzed for soil texture,total nitrogen,organic carbon,phosphorus and heavy metals(Fe,Mn,Cr,Cu,Ni,Pb,Zn and Cd).The distinct seasonal...Core sediments from the Muthupettai mangroves on the southeast coast of India were analyzed for soil texture,total nitrogen,organic carbon,phosphorus and heavy metals(Fe,Mn,Cr,Cu,Ni,Pb,Zn and Cd).The distinct seasonal variation in the distribution of metals in the sediments was observed.The minimum concentration was recorded in river mouth and the maximum was in lagoon.High metal concentration in sediment was observed during monsoon and low concentration in summer.The total nu-trient in lagoon and river mouth was recorded in the range of 4.528 to 8.526 mg g-1 for organic carbon,2.213 to 10.5 mg g-1 for nitro-gen and 0.824 to 7.22 mg g-1.展开更多
The Gulf of Kachchh in western India, with its arid climate, large semi-diurnal tidal amplitudes, negative water balance and near-pristine water quality, is being extensively developed as oil importing bases for econo...The Gulf of Kachchh in western India, with its arid climate, large semi-diurnal tidal amplitudes, negative water balance and near-pristine water quality, is being extensively developed as oil importing bases for economic reasons in connection with its proximity to the oil exporting countries of the Middle East. Besides, new coral rubbings were sighted in Jakhau, north-western Gulf of Kachchh. Dredging in Mandvi of the north Gulf covering 3.5 km2 revealed a similar assortment of live corals with their associated flora and fauna. These pioneering observations demonstrate that there exist live corals of young polyps-colony of Favia sp. belonging to the family Faviidae in the north-western Gulf of Kachchh. The environmental parameters there were carefully recorded as: surface water temperature (℃) varying from 29 to 31.8, salinity (ppt), pH, dissolved oxygen (mgL-1) and total suspended solids (mgL-1) in the ranges of 37- 43.5, 7.7- 8.45, 5.4 - 6.8 and 11- 31, respectively.展开更多
文摘This paper presents a nonlinear control approach to variable speed wind turbine(VSWT)with a wind speed estimator.The dynamics of the wind turbine(WT)is derived from single mass model.In this work,a modified Newton Raphson estimator has been considered for exact estimation of effective wind speed.The main objective of this work is to extract maximum energy from the wind at below rated wind speed while reducing drive train oscillation.In order to achieve the above objectives,VSWT should operate close to the optimal power coefficient.The generator torque is considered as the control input to achieve maximum energy capture.From the literature,it is clear that existing linear and nonlinear control techniques suffer from poor tracking of WT dynamics,increased power loss and complex control law.In addition,they are not robust with respect to input disturbances.In order to overcome the above drawbacks,adaptive fuzzy integral sliding mode control(AFISMC)is proposed for VSWT control.The proposed controller is tested with different types of disturbances and compared with other nonlinear controllers such as sliding mode control and integral sliding mode control.The result shows the better performance of AFISMC and its robustness to input disturbances.In this paper,the discontinuity in integral sliding mode controller is smoothed by using hyperbolic tangent function,and the sliding gain is adapted using a fuzzy technique which makes the controller more robust.
基金the foundational support by the Fundamental Research Funds for the Central Universities(BLX202132)the foundational support by the Beijing Youth Talent Funding Program-Visiting program for young foreign scholars(Q2023043)IIT(BHU)Varanasi.Part of the element in Fig.1 is designed by Freepik.
文摘Due to their extraordinary durability and thermal stability,Epoxy Resin Thermosets(ERTs)are essential in various industries.However,their poor recyclability leads to unacceptable environmental pollution.In this study,Wu et al.successfully synthesized a completely bio-based ERT using lignocellulose-derived building blocks which exhibit outstanding thermal and mechanical properties.Remarkably,these bio-materials degrade via methanolysis without the need of any catalyst,presenting a smart and cost-effective recycling strategy.Furthermore,this approach could be employed for fabricating reusable composites comprising glass fiber and plant fiber,thereby expanding its applications in sustainable transportation,coatings,paints or biomedical devices.
文摘To optimize the energy capture from the wind,wind turbine(WT)should operate at variable speed.Based on the wind speed,the operating regions of the WT are divided into two parts:below and above the rated wind speed.The main aim at below rated wind speed is to maximize the energy capture from the wind with reduced oscillation on the drive train.At above rated wind speed,the aim is to maintain the rated power by using pitch control.This paper presents the control of WT at below rated wind speed by using backstepping sliding mode control(BSMC).In BSMC,generator torque is considered as the control input that depends on the optimal rotor speed.Usually,this optimal rotor speed is derived from effective wind speed.In this paper,effective wind speed is estimated from aerodynamic torque and rotor speed by using the modified Newton Rapshon(MNR)algorithm.Initially,a conventional sliding mode controller(SMC)is applied to the WT,but the performance of the controller was found to be less robust with respect to disturbances.Generally,WT external disturbance is not predictable.To overcome the above drawback,BSMC is proposed and both the controllers are tested with mathematical model and finally validated with the fatigue,aerodynamics,structures,and turbulence(FAST)WT simulator in the presence of disturbances.From the results,it is concluded that the proposed BSMC is more robust than conventional SMC in the presence of disturbances.
基金the National Remote Sensing Center, ISRO-Hyderabad for providing financial supports
文摘The present study revealed proliferation of macro-algae modifying coral reef ecosystems in a different manner due to diseases and sedimentations in the Mandapam group of islands in the Gulf of Mannar. Benthic surveys were conducted with major attack of seven coral reefs diseases with high sedimentation rate, nine species of fleshy macro-algae(Turbinaria ornata, Turbinaria conaides, Caulerpa scalpelliformis, Caulerpa racemosa, Kappaphycus alvarezii, Padina gymnosphora, Sargassum wightii, Ulva reticulata and Calurpa lentillifera) proliferation against major corals life forms(Acropora branching, Acropora digitate, Acropora tabulate, coral massive, coral submassive, coral foliose and coral encrusting). The results confirm that diseased corals most favor to macro-algae growth(15.27%) rather than the sedimentation covered corals(8.24 %). In the degradation of coral life forms, massive corals were more highly damaged(7.05%) than any other forms. Within a short period of time(May to September), coral coverage shrank to 17.4% from 21.9%, macro-algae increased 23.51% and the average sedimentation rate attained 77.52 mg cm^(-2) d^(-1) with persisting coral reef diseases of 17.59%. The Pearson correlation showed that the coral cover decreased with increasing macro-algae growth, which was statistically significant(r =-0.774, n = 100, P < 0.0005). The proliferation of the various macro-algae C. scalpellifrmis, T. ornata, C. racemosa, T. conaides, U. reticulata, S. wightii, K. alvarezii, P. gymnosphora and C. lentillifera increased with percentages of 6.0, 5.8, 5.7, 4.9, 4.2, 3.7, 2.7 and 1.9, respectively. If this trend continues, the next generation of new recruit corals will undoubtedly lead to a phase shift in Gulf of Mannar corals.
文摘The wireless sensor network (WSN) is one of the budding exploring areas and fast rising fields in wireless communications. The sensor nodes in the network are generally small-size, low-cost, low-power and multi-function capabilities. Wireless sensor networks (WSNs) are used for various applications;since numerous sensor nodes are usually deployed on remote and inaccessible places, the employment and preservation should be easy and scalable. Sensor nodes in the field being run out of energy quickly has been an issue and many energy efficient routing protocols have been proposed to solve this problem and preserve the long life of the network. This paper work proposes a hierarchical based node activation routing technique which shows energy efficiency. This technique selects cluster head with highest residual energy in each communication round of transmission to the base station from the cluster heads. Hierarchical based node activation routing technique with different levels of hierarchy simulation results prolongs the lifetime of the network compared to other clustering schemes and communication rounds of simulation increase significantly.
基金supported by NIH grants(DK56292,DK115812,U54MD007602-33S3,S21MD000101,and CA164133).
文摘Dear Editor,The promptness and continuous expansion of the coronavirus disease 2019(COVID-19)pandemic,elicited by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)and its variants,has presented an unprecedented impact on human health(WHO Coronavirus(COVID-19)Dashboard,2021).Although vaccination has attenuated the severe symptoms,there is no specific antiviral medication available for preventing the viral spread(Drayman et al.,2021).
基金supported by the National Key Research and Development Program of China (2017YFD0200400, 2017YFD0201108, SQ2017ZY06102)the National Natural Science Foundation of China (20090073110048)+1 种基金the National Modern Agriculture Industry Technique Systems (CARS-02)Special Project of Basic Work Project for Science and Technology (2014FY120900)
文摘This study reports a strain of Trichoderma harzianum CCTCC-SBW0162 with potential to enhance biocontrol activity against gray mold pathogen, Botrytis cinerea, and with a pivotal role in tomato(Solanum esculentum) plant growth enhancement. A total of 254 Trichoderma isolates were screened by in vitro antagonistic assay. Of these, 10 were selected for greenhouse experiments based on their greater inhibition of B. cinerea.The in vitro antagonistic assay and greenhouse experiments indicated that T. harzianum CCTCC-SBW0162 gave the highest inhibition rate(90.6%) and disease reduction(80.7%). Also, to study the possible mechanism associated with antifungal activity of CCTCC-SBW0162 against B. cinerea, molecular docking was used to assess the interactions between CCTCC-SBW0162-derived metabolites, and pathogencity and virulence related proteins of B. cinerea. The molecular docking results indicated that the combination of harzianopyridone,harzianolide and anthraquinone C derived from CCTCCSBW0162 could synergistically improve antifungal activity against B. cinerea through the inhibition/modification of pathogenicity and virulence related proteins.However, this computerized modeling work emphasized the need for further study in the laboratory to confirm the effect T. harzianum-derived metabolites against the proteins of B. cinerea and their interactions.
文摘Phytomediated synthesis of metal oxide nanoparticles has become a key research area in nanotechnology due to its wide applicability in various biomedical fields. The present work explores the biosynthesis of zinc oxide nanoparticles（ZnO-NPs） using Leucaena leucocephala leaf extract. The synthesised ZnO-NPs were characterised by ultraviolet-visible（UV-Vis） spectroscopy, scanning electron microscopy（SEM）, energydispersive X-ray spectroscopy（EDX）, Fourier transform infrared spectroscopy（FTIR）, X-ray diffraction（XRD）,transmission electron microscopy（TEM） and selected area electron diffraction（SAED） studies. Biosynthesised ZnONPs are found to have wurtzite hexagonal structure with particles distributed in the range of 50-200 nm as confirmed by TEM studies. The anticancer activity of ZnONPs against MCF-7（breast cancer） and PC-3（human prostate cancer） cell lines was evaluated using 3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide（MTT） assay. From the assay, biosynthesised ZnO-NPs have better cytotoxic activity on PC-3 cell lines than MCF-7 cell lines. The in vitro cytotoxicity studies of biosynthesised ZnO-NPs against Dalton lymphoma ascites（DLA）cells reveal better antitumor activity of 92% inhibition with concentration of 200 μg·ml-1 of ZnO-NPs,and as the concentration increases, the anticancer efficiency as well increases, and also, it has excellent photocatalytic activity to degrade crystal violet dye in aqueous solution after irradiation of 90 min. The result suggests that the green synthesis of ZnO-NPs could be easily recovered and reused several times without any significant loss of the catalytic activity. The advantage of this technique lies in its low cost, easily climb able and non-use of toxic agents.
基金This work was supported in part by grants from the National Natural Science Foundation of China(81630080,31430054,91854203,31301105,31320103904,31621002,31671405,91853115,21922706,81572283,31271518,31471275,and 31870759)National Key Research and Development Program of China(2017YFA0503600 and 2016YFA0100500)+2 种基金Ministry of Education(IRT_17R102 and 20113402130010)the Strategic Priority Research Program of Chinese Academy of Sciences(XDB19000000)Central University Grants WK2340000066.
文摘Ezrin,a membrane–cytoskeleton linker protein,plays an essential role in cell polarity establishment,cell migration,and division.Recent studies show that ezrin phosphorylation regulates breast cancer metastasis by promoting cancer cell survivor and promotes intrahepatic metastasis via cell migration.However,it was less characterized whether there are additional post-translational modifications and/or post-translational crosstalks on ezrin underlying context-dependent breast cancer cell migration and invasion.Here we show that ezrin is acetylated by p300/CBP-associated factor(PCAF)in breast cancer cells in response to CCL18 stimulation.Ezrin physically interacts with PCAF and is a cognate substrate of PCAF.The acetylation site of ezrin was mapped by mass spectrometric analyses,and dynamic acetylation of ezrin is essential for CCL18-induced breast cancer cell migration and invasion.Mechanistically,the acetylation reduced the lipid-binding activity of ezrin to ensure a robust and dynamic cycling between the plasma membrane and cytosol in response to CCL18 stimulation.Biochemical analyses show that ezrin acetylation prevents the phosphorylation of Thr567.Using atomic force microscopic measurements,our study revealed that acetylation of ezrin induced its unfolding into a dominant structure,which prevents ezrin phosphorylation at Thr567.Thus,these results present a previously undefined mechanism by which CCL18-elicited crosstalks between the acetylation and phosphorylation on ezrin control breast cancer cell migration and invasion.This suggests that targeting PCAF signaling could be a potential therapeutic strategy for combating hyperactive ezrin-driven cancer progression.
基金the course of study/project as part of the Meteorology and Oceanography (MOP-2) Program of ISRO
文摘Seasonal and inter-annual variability of hydrological parameters and its impact on chlorophyll distribution was studied from January 2009 to December 2011 at four coastal stations along the southwest Bay of Bengal. Statistical analysis （principal component analysis （PCA）, two-way analysis of variance （ANOVA） and correlation analysis） showed the significant impact of hydrological parameters on chlorophyll distribution in the study area. The ranges of different parameters recorded were 23.8-33.8℃ （SST）, 4.00-36.00 （salinity）, 7.0-9.2 （pH）, 4.41-8.32 mg/L （dissolved oxygen）, 0.04-2.45 μmol/L （nitrite）, 0.33-16.10 μmol/L （nitrate）, 0.02-2.51 μmol/L （ammonia）, 0.04-3.32 μmol/L （inorganic phosphate）, 10.09-85.28 μmol/L （reactive silicate） and 0.04-13.8 μg/L （chlorophyll）. PCA analysis carried out for different seasons found variations in the relationship between physico-chemical parameters and chlorophyll in which nitrate and chlorophyll were positively loaded at PC1 （principal component 1） during spring inter-monsoon and at PC2 （principal component 2） during other seasons. Likewise correlation analysis also showed significant positive relationship between chlorophyll and nutrients especially with nitrate （~0.734）. Distribution of hydrobiological parameters between stations and distances was significantly varying as evidenced from the ANOVA results. The study found that the spatial and temporal distribution of chlorophyll was highly dependent on the availability of nutrients especially, nitrate in the southwest Bay of Bengal coastal waters.
文摘The total benthic macrofauna consisting of 62 species in 5 groups,viz. crustaceans(18),gastropods(17),bivalves(16),polychaetes(9) and fishes(2),was recorded in western Kachchh mangroves near Gujarat. The population densities of benthic macro-fauna ranged from 424 to 2393 ind.m-2,the diversity ranged from 1.84 to 2.45 bits ind.-1,the richness varied between 0.82 and 0.98,and the evenness varied between 0.64 and 0.81. Two maximum diversity values were recorded during winter and summer. The salin-ity ranged from 34 to 44,temperature varied between 17 and 37 ℃,and the acidity ranged from 7 to 8.9.
基金supported by grants from the National Key Re-search and Development Program of China(2017YFA0503600 and 2016YFA0100500)the National Natural Science Founda-tion of China(31621002,32090040,91854203,21922706,91853115,92153302,22177106,92053104,31970655,and 32100612)+2 种基金the Ministry of Education(IRT_17R102),Anhui Provincial Natural Science Foundation(2108085J15)the Strate-gic Priority Research Program of the Chinese Academy of Sci-ences(XDB19040000)the Fundamental Research Funds for the Central Universities(WK2070000066 and WK2070000194).
文摘Stable transmission of genetic information during cell division requires faithful mitotic spindle assembly and chromosome segregation.In eukaryotic cells,nuclear envelope breakdown(NEBD)is required for proper chromosome segregation.Although a list of mitotic kinases has been implicated in NEBD,how they coordinate their activity to dissolve the nuclear envelope and protein machinery such as nuclear pore complexes was unclear.Here,we identified a regulatory mechanism in which Nup62 is acetylated by TIP60 in human cell division.Nup62 is a novel substrate of TIP60,and the acetylation of Lys432 by TIP60 dissolves nucleoporin Nup62-Nup58-Nup54 complex during entry into mitosis.Importantly,this acetylation-elicited remodeling of nucleoporin complex promotes the distribution of Nup62 to the mitotic spindle,which is indispensable for orchestrating correct spindle orientation.Moreover,suppression of Nup62 perturbs accurate chromosome segregation during mitosis.These results establish a previously uncharacterized regulatory mechanism in which TIP60-elicited nucleoporin dynamics promotes chromosome segregation in mitosis.
基金the Technology Mission Division(TMD),Department of Science and Technology(DST),New Delhi,India,for a research Grant under Materials for Energy Storage(MES)Scheme No.DST/TMD/MES/2K17/29International Bilateral Cooperation Division(TMD),Department of Science and Technology(DST),New Delhi,India for a research grant under Indo-German Project scheme no.INT/FRG/DAAD/P-09/2018Department of Science and Technology for the financial assistance under DST-Inspire fellowship scheme(IF170869).
文摘Electrochemical energy storage devices(EESs)play a crucial role for the construction of sustainable energy storage system from the point of generation to the end user due to the intermittent nature of renewable sources.Additionally,to meet the demand for next-generation electronic applications,optimizing the energy and power densities of EESs with long cycle life is the crucial factor.Great e orts have been devoted towards the search for new materials,to augment the overall performance of the EESs.Although there are a lot of ongoing researches in this field,the performance does not meet up to the level of commercialization.A further understanding of the charge storage mechanism and development of new electrode materials are highly required.The present review explains the overview of recent progress in supercapattery devices with reference to their various aspects.The di erent charge storage mechanisms and the multiple factors involved in the performance of the supercapattery are described in detail.Moreover,recent advancements in this supercapattery research and its electrochemical performances are reviewed.Finally,the challenges and possible future developments in this field are summarized.
文摘This work focuses on the fuzzy controller for the proposed three-phase interleaved Step-up converter(ISC).The fuzzy controller for the proposed ISC converters for electric vehicles has been discussed in detail.The proposed ISC direct current(DC-DC)converter could also be used in automobiles,satellites,industries,and propulsion.To enhance voltage gain,the proposed ISC Converter combines boost converter and interleaved converter(IC).This design also reduces the number of switches.As a result,ISC converter switching losses are reduced.The proposed ISC Converter topology can produce a 143 V output voltage and 1 kW of power.Due to the high voltage gain of this converter design,it is suitable for medium and high-power systems.The proposed ISC Converter topology is simulated in MATLAB/Simulink.The simulated output displays a high output voltage.But the output voltage contains maximum ripples.Fuzzy proposes an ISC Converter which makes closed loop responsiveness and reduces the output voltage ripple.The proposed ISC converter has the lowest ripple output voltage,which is less than 2%,because the duty cycle is regulated using the fuzzy logic controller.It offers high voltage gain,minimal ripple,and low switching loss.The performance of the proposed converter is compared to that of the fuzzy and Pro-portional Integral(PI)controllers implemented in MATLAB.
基金the Ministry of Earth Science for financial support
文摘This work quantified the total carbon and 12 other sediment characteristics at 10 soil depths, in planted and or natural mangrove forests in comparison with non-vegetated soil for four seasons of the year 2009-2010 in the Vellar-Coleroon estuarine complex, India. The sedi- ment characteristics varied significantly between mangrove-vegetated and non-vegetated habitats or seasons of analysis, but not between soil depths. The mangrove sediments were rich in total carbon and total or- ganic carbon as compared to non-mangrove sediments （p 〈0.01）. Total carbon was 98.2% higher in mature mangroves and 41.8% in planted mangroves than that in non-mangrove soil. Total organic carbon was as much as 2.5 times greater in mature mangroves and 2 times greater in planted mangroves than that in unvegetated soil. Carbon contents also varied many fold by season. Total carbon content was 8.6 times greater during pre-monsoon, 4.1 times greater during post-monsoon and 2.5 times greater during monsoon than during summer （P〈0.01 in all cases）. Similarly, total organic carbon was 5.9 times greater during pre-monsoon, 3.1 times greater during post-monsoon and 69% greater during monsoon than during summer. In general, higher levels of sediment carbon were recorded during pre and post-monsoon seasons than during other seasons. Total carbon concentration was correlated negatively to temperature, sand and phosphorus （P 〈0.01）; positively correlated with redox potential, silt, clay, C/N ratio, potassium （P 〈0.01） and nitrogen （P〈0.05）; but not correlated with soil depth, pH or salinity. This work revealed that the carbon burial was rapid at the annual rate of 2.8% for total carbon, and 6.7% for total organic carbon in mangrove-planted sediment. Cleating of mangroves can result in significantly and rapidly reduced carbon stores.Our study highlights the importance of natural and plantation mangrove stands for conserving sediment carbon in the tropical coastal domain.
文摘The finfish and shellfish resources were assessed quantitatively and qualitatively in regard to their abundance in creek waters at three sites within a period of two years, fi＇om January 1999 to December 2000, in the western mangrove areas of Kachchh. The catch rate varied from 0.69 to 6.99kg·h^-1. It was low during monsoon （July to October）, which could be due to the freshwater-flow-induced salinity reduction in all the sites. Among 38 species recorded, 5 were shellfish and 33 were finfish. The spawning period of fishes was found to be during summer and early monsoon period （May to August）. Surface water temperatures varied from 17℃ to 37 ℃. Salinity values varied from 34 to 44 and the pH ranged between 7 and 8.9. Variation in dissolved oxygen content was from 3.42 to 5.85 mL L^-1. The high fishery densities in these semi arid mangrove creek areas were recorded during monsoon and early winter season.
基金funded by Deanship of Scientific Research(DSR),King Abdulaziz University,Jeddah,under grant No.(DF-779-130-1441)DSR technical and financial support.
文摘The exploration of polymer electrolyte in the field of dye sensitized solar cell(DSSC) can contribute to increase the invention of renewable energy applications. In the present work, the influence of imidazole on the poly(vinylidene fluoride)(PVDF)–poly(methyl methacrylate)(PMMA)–Ethylene carbonate(EC)–KI–I2 polymer blend electrolytes has been evaluated. The different weight percentages of imidazole added into polymer blend electrolytes have been prepared by solution casting. The prepared films were characterized by Fourier transform infrared spectroscopy(FTIR), X-ray diffraction(XRD), thermogravimetric analysis(TGA), UV–visible spectra, photoluminescence spectra and impedance spectroscopy. The surface roughness texture of the film was analyzed by atomic force microscopy(AFM). The ionic conductivity of the optimized polymer blend electrolyte was determined by impedance measurement, which is 1.95 × 10-3 S·cm-1 at room temperature. The polymer electrolyte containing 40 wt% of imidazole content exhibits the highest photo-conversion efficiency of 3.04%under the illumination of 100 m W·cm-2. Moreover, a considerable enhancement in the stability of the DSSC device was demonstrated.
基金Project supported by Department of Science and Technology(DST)under research project No.SR/FTP/MS-039/2011
文摘We scrutinize the problem of robust H∞control for a class of Markovian jump uncertain systems with interval timevarying and distributed delays. The Markovian jumping parameters are modeled as a continuous-time finite-state Markov chain. The main aim is to design a delay-dependent robust H∞control synthesis which ensures the mean-square asymptotic stability of the equilibrium point. By constructing a suitable Lyapunov–Krasovskii functional（LKF）, sufficient conditions for delay-dependent robust H∞control criteria are obtained in terms of linear matrix inequalities（LMIs）. The advantage of the proposed method is illustrated by numerical examples. The results are also compared with the existing results to show the less conservativeness.
文摘Core sediments from the Muthupettai mangroves on the southeast coast of India were analyzed for soil texture,total nitrogen,organic carbon,phosphorus and heavy metals(Fe,Mn,Cr,Cu,Ni,Pb,Zn and Cd).The distinct seasonal variation in the distribution of metals in the sediments was observed.The minimum concentration was recorded in river mouth and the maximum was in lagoon.High metal concentration in sediment was observed during monsoon and low concentration in summer.The total nu-trient in lagoon and river mouth was recorded in the range of 4.528 to 8.526 mg g-1 for organic carbon,2.213 to 10.5 mg g-1 for nitro-gen and 0.824 to 7.22 mg g-1.
基金supported by the Chinese Academy of Sciences Research Fellowship for International Young Researchers for M. Rajkumarthe Knowledge Innovation Project of The Chinese Academy of Sciences (KZCX2-YW-QN205, KZCX2-YW-213-2)the National High Technology Research and Development Program of China (2006AA09Z179) for Dr. Jun Sun
文摘The Gulf of Kachchh in western India, with its arid climate, large semi-diurnal tidal amplitudes, negative water balance and near-pristine water quality, is being extensively developed as oil importing bases for economic reasons in connection with its proximity to the oil exporting countries of the Middle East. Besides, new coral rubbings were sighted in Jakhau, north-western Gulf of Kachchh. Dredging in Mandvi of the north Gulf covering 3.5 km2 revealed a similar assortment of live corals with their associated flora and fauna. These pioneering observations demonstrate that there exist live corals of young polyps-colony of Favia sp. belonging to the family Faviidae in the north-western Gulf of Kachchh. The environmental parameters there were carefully recorded as: surface water temperature (℃) varying from 29 to 31.8, salinity (ppt), pH, dissolved oxygen (mgL-1) and total suspended solids (mgL-1) in the ranges of 37- 43.5, 7.7- 8.45, 5.4 - 6.8 and 11- 31, respectively.
