The shift towards the renewable energy market for carbon-neutral power generation has encouraged different governments to come up with a plan of action.But with the endorsement of renewable energy for harsh environmen...The shift towards the renewable energy market for carbon-neutral power generation has encouraged different governments to come up with a plan of action.But with the endorsement of renewable energy for harsh environmental conditions like sand dust and snow,monitoring and maintenance are a few of the prime concerns.These problems were addressed widely in the literature,but most of the research has drawbacks due to long detection time,and high misclassification error.Hence to overcome these drawbacks,and to develop an accurate monitoring approach,this paper is motivated toward the understanding of primary failure concerning a grid-connected photovoltaic(PV)system and highlighted along with a brief overview on existing fault detection methodology.Based on the drawback a data-driven machine learning approach has been used for the identification of fault and indicating the maintenance unit regarding the operation and maintenance requirement.Further,the system was tested with a 4 kWp grid-connected PV system,and a decision tree-based algorithm was developed for the identification of a fault.The results identified 94.7%training accuracy and 14000 observations/sec prediction speed for the trained classifier and improved the reliability of fault detection nature of the grid-connected PV operation.展开更多
The excitation function of the 58Ni(n,p)58Co reaction was measured using the well-established neutron activation technique andγ-ray spectroscopy.Neutrons in the energy range of 1.7 to 2.7 MeV were generated using the...The excitation function of the 58Ni(n,p)58Co reaction was measured using the well-established neutron activation technique andγ-ray spectroscopy.Neutrons in the energy range of 1.7 to 2.7 MeV were generated using the 7Li(p,n)reaction.The neutron flux was measured using the standard 115In(n,n’)115mIn monitor reaction.The results of the neutron spectrum averaged cross-section of 58Ni(n,p)58Co reactions were compared with existing cross-section data available in the EXFOR data library as well as with various evaluated data libraries such as ENDF/B-VIII.0,JEFF-3.3,JENDL-4.0,and CENDL-3.2.Theoretical calculations were performed using the nuclear reaction code TALYS.Various nuclear level density(NLD)models were tested,and their results were compared with the present findings.Realistic NLDs were also obtained through the spectral distribution method(SDM).The cross-section results,along with the absolute errors,were obtained by investigating the uncertainty propagation and using the covariance technique.Corrections forγ-ray true coincidence summing,low-energy background neutrons,andγ-ray self attenuation were performed.The experimental cross-section obtained in the present study is consistent with previously published experimental data,evaluated libraries,and theoretical calculations carried out using the TALYS code.展开更多
This study presents a rapid and versatile low-cost sample-to-answer system for SARS-CoV-2 diagnostics.The system integrates the extraction and purification of nucleic acids,followed by amplification via either reverse...This study presents a rapid and versatile low-cost sample-to-answer system for SARS-CoV-2 diagnostics.The system integrates the extraction and purification of nucleic acids,followed by amplification via either reverse transcriptionquantitative polymerase chain reaction(RT–qPCR)or reverse transcription loop-mediated isothermal amplification(RT–LAMP).By meeting diverse diagnostic and reagent needs,the platform yields testing results that closely align with those of commercial RT-LAMP and RT‒qPCR systems.Notable advantages of our system include its speed and costeffectiveness.The assay is completed within 28 min,including sample loading(5 min),ribonucleic acid(RNA)extraction(3 min),and RT-LAMP(20 min).The cost of each assay is≈$9.5,and this pricing is competitive against that of Food and Drug Administration(FDA)-approved commercial alternatives.Although some RNA loss during on-chip extraction is observed,the platform maintains a potential limit of detection lower than 297 copies.Portability makes the system particularly useful in environments where centralized laboratories are either unavailable or inconveniently located.Another key feature is the platform’s versatility,allowing users to choose between RT‒qPCR or RT‒LAMP tests based on specific requirements.展开更多
This work focuses on the fabrication and characterization of Chemical Field-Effect Transistor(ChemFET)gas nanosensor arrays based on single nanowire(SNW).The fabrication processes include micro and nanofabrication tec...This work focuses on the fabrication and characterization of Chemical Field-Effect Transistor(ChemFET)gas nanosensor arrays based on single nanowire(SNW).The fabrication processes include micro and nanofabrication techniques enabled by a combination of ultraviolet(UV)and e-beam lithography to build the ChemFET structure.Results show the integration and connection of SNWs across the multiple pairs of nanoelectrodes in the ChemFET by dielectrophoresis process(DEP)thanks to the incorporation of alignment windows(200-300 nm)adapted to the diameter of the NWs.Measurements of the SNW ChemFET array's output and transfer characteristics prove the influence of gate bias on the drain current regulation.Tests upon hydrogen(H_(2))and nitrogen dioxide(NO_(2))as analyte models of reducing and oxidizing gases show the ChemFET sensing functionality.Moreover,results demonstrate better response characteristics to H_(2)when the ChemFET operates in the subthreshold regime.The design concepts and methods proposed for fabricating the SNW-based ChemFET arrays are versatile,reproducible,and most likely adaptable to other systems where SNW arrays are required.展开更多
A method is presented to determine significant frequencies of oscillations of cavitation structures from high-speed camera recordings of a flow around a 2-D hydrofoil. The top view of the suction side of an NACA 2412 ...A method is presented to determine significant frequencies of oscillations of cavitation structures from high-speed camera recordings of a flow around a 2-D hydrofoil. The top view of the suction side of an NACA 2412 hydrofoil is studied in a transparent test section of a cavitation tunnel for selected cloud cavitation regimes with strong oscillations induced by the leading-edge cavity shedding. The ability of the method to accurately determine the dominant oscillation frequencies is confirmed by pressure measure- ments. The method can resolve subtle flow characteristics that are not visible to the naked eye. The method can be used for non- invasive experimental studies of oscillations in cavitating flows with adequate visual access when pressure measurements are not available or when such measurements would disturb the flow.展开更多
The concept of an HX-group is an upgrade of the concept of a group,in which a new operation is defined on the family of non-empty subsets of a group.If this new support set together with the new operation is a group,t...The concept of an HX-group is an upgrade of the concept of a group,in which a new operation is defined on the family of non-empty subsets of a group.If this new support set together with the new operation is a group,then we call it an HX-group.On the other hand,a hyperoperation is a mapping having the same codomain as the operation of an HX-group,i.e.,the family of non-empty subsets of the initial set,but a different domain-the set itself.This could be(and was indeed)a source of confusion,which is clarified in this paper.Moreover,HX-groups naturally lead to constructions of hypergroups.The links between these two algebraic concepts are presented,with the aim of reviving the old notion of an HX-group in the current research on algebraic hyperstructures.One of such existing links and one newly established link are also discussed.展开更多
We study a problem concerning the compulsory behavior of the solutions of systems of discrete equations u（k ＋ 1） = F（k, u（k））, k ∈ N（a） = {a, a ＋ 1, a ＋ 2 }, a ∈ N,N= {0, 1,... } and F ： N（a） × R^...We study a problem concerning the compulsory behavior of the solutions of systems of discrete equations u（k ＋ 1） = F（k, u（k））, k ∈ N（a） = {a, a ＋ 1, a ＋ 2 }, a ∈ N,N= {0, 1,... } and F ： N（a） × R^n→R^n. A general principle for the existence of at least one solution with graph staying for every k ∈ N（a） in a previously prescribed domain is formulated. Such solutions are defined by means of the corresponding initial data and their existence is proved by means of retract type approach. For the development of this approach a notion of egress type points lying on the defined boundary of a given domain and with respect to the system considered is utilized. Unlike previous investigations, the boundary can contain points which are not points of egress type, too. Examples are inserted to illustrate the obtained result.展开更多
基金The authors extend their appreciation to the Deputyship for Research&Innovation,Ministry of Education in Saudi Arabia for funding this research work through the project number“IFPHI-022-135-2020”and King Abdulaziz University,DSR,Jeddah,Saudi Arabia.
文摘The shift towards the renewable energy market for carbon-neutral power generation has encouraged different governments to come up with a plan of action.But with the endorsement of renewable energy for harsh environmental conditions like sand dust and snow,monitoring and maintenance are a few of the prime concerns.These problems were addressed widely in the literature,but most of the research has drawbacks due to long detection time,and high misclassification error.Hence to overcome these drawbacks,and to develop an accurate monitoring approach,this paper is motivated toward the understanding of primary failure concerning a grid-connected photovoltaic(PV)system and highlighted along with a brief overview on existing fault detection methodology.Based on the drawback a data-driven machine learning approach has been used for the identification of fault and indicating the maintenance unit regarding the operation and maintenance requirement.Further,the system was tested with a 4 kWp grid-connected PV system,and a decision tree-based algorithm was developed for the identification of a fault.The results identified 94.7%training accuracy and 14000 observations/sec prediction speed for the trained classifier and improved the reliability of fault detection nature of the grid-connected PV operation.
基金One of the authors(A.H.)sincerely acknowledges the Department of Science and Technology(DST),Government of Indiafor the INSPIRE Fellowship award(No.DST/INSPIRE Fellowship/2019/IF190924)+1 种基金partial support from the SERBwith grants No.SIR/2022/000566 and CRG/2021/000101,respectively。
文摘The excitation function of the 58Ni(n,p)58Co reaction was measured using the well-established neutron activation technique andγ-ray spectroscopy.Neutrons in the energy range of 1.7 to 2.7 MeV were generated using the 7Li(p,n)reaction.The neutron flux was measured using the standard 115In(n,n’)115mIn monitor reaction.The results of the neutron spectrum averaged cross-section of 58Ni(n,p)58Co reactions were compared with existing cross-section data available in the EXFOR data library as well as with various evaluated data libraries such as ENDF/B-VIII.0,JEFF-3.3,JENDL-4.0,and CENDL-3.2.Theoretical calculations were performed using the nuclear reaction code TALYS.Various nuclear level density(NLD)models were tested,and their results were compared with the present findings.Realistic NLDs were also obtained through the spectral distribution method(SDM).The cross-section results,along with the absolute errors,were obtained by investigating the uncertainty propagation and using the covariance technique.Corrections forγ-ray true coincidence summing,low-energy background neutrons,andγ-ray self attenuation were performed.The experimental cross-section obtained in the present study is consistent with previously published experimental data,evaluated libraries,and theoretical calculations carried out using the TALYS code.
基金support of Grant No.52150710541 from the National Natural Science Foundation of China(NSFC),P.R.of ChinaGrant No.2018YFE0109000 from the Ministry of Science and Technology of the P.R.of China+2 种基金Petra Vopařilováand other members of Mendel University would like to acknowledge financial support from the Internal Grant Agency of the Faculty of AgriSciences,Mendel University in Brno(No.AF-IGA2023-IP-030)Haoqing Zhang would like to acknowledge the financial support of Grant No.2023-JC-QN-0130 from the Natural Science Basic Research Program of Shaanxi Province,P.R.ChinaGrant No.2023M732815 from the P.R.China Postdoctoral Science Foundation.
文摘This study presents a rapid and versatile low-cost sample-to-answer system for SARS-CoV-2 diagnostics.The system integrates the extraction and purification of nucleic acids,followed by amplification via either reverse transcriptionquantitative polymerase chain reaction(RT–qPCR)or reverse transcription loop-mediated isothermal amplification(RT–LAMP).By meeting diverse diagnostic and reagent needs,the platform yields testing results that closely align with those of commercial RT-LAMP and RT‒qPCR systems.Notable advantages of our system include its speed and costeffectiveness.The assay is completed within 28 min,including sample loading(5 min),ribonucleic acid(RNA)extraction(3 min),and RT-LAMP(20 min).The cost of each assay is≈$9.5,and this pricing is competitive against that of Food and Drug Administration(FDA)-approved commercial alternatives.Although some RNA loss during on-chip extraction is observed,the platform maintains a potential limit of detection lower than 297 copies.Portability makes the system particularly useful in environments where centralized laboratories are either unavailable or inconveniently located.Another key feature is the platform’s versatility,allowing users to choose between RT‒qPCR or RT‒LAMP tests based on specific requirements.
基金the financial support of theresearch by the Slovak Grant Agency VEGA project No.1/0211/12 and VVGS 51/12-13project CZ.1.07/2.3.00/30.0039 of Brno University of Tech-nology
基金This work was supported by the Czech Science Foundation(GAČR,No.22-14886S)the MCIN/AEI/10.13039/501100011033(No.PID2019-107697RBC42(ERDF A way of making Europe)).
文摘This work focuses on the fabrication and characterization of Chemical Field-Effect Transistor(ChemFET)gas nanosensor arrays based on single nanowire(SNW).The fabrication processes include micro and nanofabrication techniques enabled by a combination of ultraviolet(UV)and e-beam lithography to build the ChemFET structure.Results show the integration and connection of SNWs across the multiple pairs of nanoelectrodes in the ChemFET by dielectrophoresis process(DEP)thanks to the incorporation of alignment windows(200-300 nm)adapted to the diameter of the NWs.Measurements of the SNW ChemFET array's output and transfer characteristics prove the influence of gate bias on the drain current regulation.Tests upon hydrogen(H_(2))and nitrogen dioxide(NO_(2))as analyte models of reducing and oxidizing gases show the ChemFET sensing functionality.Moreover,results demonstrate better response characteristics to H_(2)when the ChemFET operates in the subthreshold regime.The design concepts and methods proposed for fabricating the SNW-based ChemFET arrays are versatile,reproducible,and most likely adaptable to other systems where SNW arrays are required.
基金supported by the Czech Science Foundation(Grant No.13-23550S)the institutional support RVO:61388998 of the Institute of Thermome-chanics of the CAS,v.v.i
文摘A method is presented to determine significant frequencies of oscillations of cavitation structures from high-speed camera recordings of a flow around a 2-D hydrofoil. The top view of the suction side of an NACA 2412 hydrofoil is studied in a transparent test section of a cavitation tunnel for selected cloud cavitation regimes with strong oscillations induced by the leading-edge cavity shedding. The ability of the method to accurately determine the dominant oscillation frequencies is confirmed by pressure measure- ments. The method can resolve subtle flow characteristics that are not visible to the naked eye. The method can be used for non- invasive experimental studies of oscillations in cavitating flows with adequate visual access when pressure measurements are not available or when such measurements would disturb the flow.
基金The first author acknowledges the financial support from the Slovenian Research Agency(research core funding No.P1-0285)The second author was supported by the FEKT-S-17-4225 grant of Brno University of Technology.
文摘The concept of an HX-group is an upgrade of the concept of a group,in which a new operation is defined on the family of non-empty subsets of a group.If this new support set together with the new operation is a group,then we call it an HX-group.On the other hand,a hyperoperation is a mapping having the same codomain as the operation of an HX-group,i.e.,the family of non-empty subsets of the initial set,but a different domain-the set itself.This could be(and was indeed)a source of confusion,which is clarified in this paper.Moreover,HX-groups naturally lead to constructions of hypergroups.The links between these two algebraic concepts are presented,with the aim of reviving the old notion of an HX-group in the current research on algebraic hyperstructures.One of such existing links and one newly established link are also discussed.
基金supported by the Grant 201/04/0580 of the Czech Grant Agency(Prague)by the Grant No 1/0026/03 and No 1/3238/06 of the Grant Agency of Slovak Republic(VEGA)
文摘We study a problem concerning the compulsory behavior of the solutions of systems of discrete equations u（k ＋ 1） = F（k, u（k））, k ∈ N（a） = {a, a ＋ 1, a ＋ 2 }, a ∈ N,N= {0, 1,... } and F ： N（a） × R^n→R^n. A general principle for the existence of at least one solution with graph staying for every k ∈ N（a） in a previously prescribed domain is formulated. Such solutions are defined by means of the corresponding initial data and their existence is proved by means of retract type approach. For the development of this approach a notion of egress type points lying on the defined boundary of a given domain and with respect to the system considered is utilized. Unlike previous investigations, the boundary can contain points which are not points of egress type, too. Examples are inserted to illustrate the obtained result.
