Timed weighted marked graphs are a subclass of timed Petri nets that have wide applications in the control and performance analysis of flexible manufacturing systems.Due to the existence of multiplicities(i.e.,weights...Timed weighted marked graphs are a subclass of timed Petri nets that have wide applications in the control and performance analysis of flexible manufacturing systems.Due to the existence of multiplicities(i.e.,weights)on edges,the performance analysis and resource optimization of such graphs represent a challenging problem.In this paper,we develop an approach to transform a timed weighted marked graph whose initial marking is not given,into an equivalent parametric timed marked graph where the edges have unitary weights.In order to explore an optimal resource allocation policy for a system,an analytical method is developed for the resource optimization of timed weighted marked graphs by studying an equivalent net.Finally,we apply the proposed method to a flexible manufacturing system and compare the results with a previous heuristic approach.Simulation analysis shows that the developed approach is superior to the heuristic approach.展开更多
Ebolaviruses,such as the highly pathogenic Ebola virus(EBOV),belong to the family Filoviridae and have caused out-breaks of severe and fatal hemorrhagic fever over the past years.Bombali virus(BOMV)is a newly discover...Ebolaviruses,such as the highly pathogenic Ebola virus(EBOV),belong to the family Filoviridae and have caused out-breaks of severe and fatal hemorrhagic fever over the past years.Bombali virus(BOMV)is a newly discovered ebolavirus from bats with unknown potential to infect humans.For most ebolaviruses,the interaction between viral glycoprotein(GP)and host receptor Niemann-Pick C1(NPC1)is crucial for viral entry and determines host tropism.Here,we analyzed the BOMV GP-mediated virus entry into human cells using our recently developed EBOV transcription-and replication-competent virus-like particle(trVLP)system.We demonstrated that while BOMV GP can be efficiently incorporated into trVLPs,it is inefficient in mediating trVLP entry into human cells.However,BOMV GP-mediated virus entry into human cells can be significantly enhanced by a few mutations in the NPC1-binding domain of GP.Furthermore,we showed that these mutations increase the binding of BOMV-GP to human NPC1.In summary,our results suggested that although wild-type BOMV does not efficiently infect human cells,the emergence of mutations in viral GP may boost its ability to spill over to humans,highlighting the importance of monitoring BOMV GP evolution in preventing potential BOMV spillover events.展开更多
Ferroelectric materials are considered to be the most competitive energy storage materials for applications in pulsed power electronics due to excellent charge-discharge properties.However,the low energy storage...Ferroelectric materials are considered to be the most competitive energy storage materials for applications in pulsed power electronics due to excellent charge-discharge properties.However,the low energy storage density is the primary problem limiting their practical application.In this study,(1−x)Na_(0.5)Bi_(0.5)TiO_(3)-xSr_(0.7)La_(0.2)TiO_(3)[(1−x)NBT-xSLT]ferroelectric ceramics are found to exhibit excellent energy storage performances through a synergistic strategy.As the SLT concentration increases,the relaxation characteristic increases significantly and the breakdown strength increases dramatically from 150 kV/cm to 220 kV/cm.The recoverable energy storage density of the _0.55NBT-0.45SLT ceramic is 2.86 J/cm^(3) with an energy storage efficiency of 88%under an electric field of 220 kV/cm.Furthermore,the ceramic with x=0.45 mol exhibited excellent energy storage stability in the ranges of 20-180℃(temperature)and 1-125 Hz(frequency).These excellent properties demonstrate the potential of(1−x)NBT-xSLT ceramics when used as dielectric capacitors in pulsed power systems.展开更多
基金supported by the National Natural Science Foundation of China(61803246,61703321)the China Postdoctoral Science Foundation(2019M663608)+2 种基金Shaanxi Provincial Natural Science Foundation(2019JQ-022,2020JQ-733)the Fundamental Research Funds for the Central Universities(JB190407)the Shaanxi Key Laboratory of Complex System Control and Intelligent Information Processing,Xi’an University of Technology(SKL2020CP03)。
文摘Timed weighted marked graphs are a subclass of timed Petri nets that have wide applications in the control and performance analysis of flexible manufacturing systems.Due to the existence of multiplicities(i.e.,weights)on edges,the performance analysis and resource optimization of such graphs represent a challenging problem.In this paper,we develop an approach to transform a timed weighted marked graph whose initial marking is not given,into an equivalent parametric timed marked graph where the edges have unitary weights.In order to explore an optimal resource allocation policy for a system,an analytical method is developed for the resource optimization of timed weighted marked graphs by studying an equivalent net.Finally,we apply the proposed method to a flexible manufacturing system and compare the results with a previous heuristic approach.Simulation analysis shows that the developed approach is superior to the heuristic approach.
基金supported by the grants from Key Research and Development Program,Ministry of Science and Technology of China(2022YFC2303300,2021YFC2300204)Shanghai Municipal Science and Technology Major Project(ZD2021CY001)+3 种基金Strategic Priority Research Program of the Chinese Academy of Sciences(XDB29010205)Shanghai International Science and Technology Cooperation Program(21430713900)Program of Shanghai Academic/Technology Research Leader(22XD1403800)to J.Z.Advanced Customer Cultivation Project of Wuhan National Biosafety Laboratory,Chinese Academy of Sciences to J.Z.and H.Y.
文摘Ebolaviruses,such as the highly pathogenic Ebola virus(EBOV),belong to the family Filoviridae and have caused out-breaks of severe and fatal hemorrhagic fever over the past years.Bombali virus(BOMV)is a newly discovered ebolavirus from bats with unknown potential to infect humans.For most ebolaviruses,the interaction between viral glycoprotein(GP)and host receptor Niemann-Pick C1(NPC1)is crucial for viral entry and determines host tropism.Here,we analyzed the BOMV GP-mediated virus entry into human cells using our recently developed EBOV transcription-and replication-competent virus-like particle(trVLP)system.We demonstrated that while BOMV GP can be efficiently incorporated into trVLPs,it is inefficient in mediating trVLP entry into human cells.However,BOMV GP-mediated virus entry into human cells can be significantly enhanced by a few mutations in the NPC1-binding domain of GP.Furthermore,we showed that these mutations increase the binding of BOMV-GP to human NPC1.In summary,our results suggested that although wild-type BOMV does not efficiently infect human cells,the emergence of mutations in viral GP may boost its ability to spill over to humans,highlighting the importance of monitoring BOMV GP evolution in preventing potential BOMV spillover events.
基金the support from the Natural Science Foundation of Inner Mongolia(2019ZD12 and 2021JQ06)the Program for“Grassland Talents”Innovation Team of Inner Mongolia(Rare Earth Modified Lead-free Ferroelectric Multilayer Ceramic Capacitors Innovative Talent Team),Scientific and Technological Development。
文摘Ferroelectric materials are considered to be the most competitive energy storage materials for applications in pulsed power electronics due to excellent charge-discharge properties.However,the low energy storage density is the primary problem limiting their practical application.In this study,(1−x)Na_(0.5)Bi_(0.5)TiO_(3)-xSr_(0.7)La_(0.2)TiO_(3)[(1−x)NBT-xSLT]ferroelectric ceramics are found to exhibit excellent energy storage performances through a synergistic strategy.As the SLT concentration increases,the relaxation characteristic increases significantly and the breakdown strength increases dramatically from 150 kV/cm to 220 kV/cm.The recoverable energy storage density of the _0.55NBT-0.45SLT ceramic is 2.86 J/cm^(3) with an energy storage efficiency of 88%under an electric field of 220 kV/cm.Furthermore,the ceramic with x=0.45 mol exhibited excellent energy storage stability in the ranges of 20-180℃(temperature)and 1-125 Hz(frequency).These excellent properties demonstrate the potential of(1−x)NBT-xSLT ceramics when used as dielectric capacitors in pulsed power systems.
