Fault diagnosis technology has been widely applied and is an important part of ensuring the safe operation of mechanical equipment.In response to the problem of frequent faults in rolling bearings,this paper designs a...Fault diagnosis technology has been widely applied and is an important part of ensuring the safe operation of mechanical equipment.In response to the problem of frequent faults in rolling bearings,this paper designs a rolling bearing fault diagnosis method based on convolutional capsule network(CCN).More specifically,the original vibration signal is converted into a two-dimensional time–frequency image using continuous wavelet transform(CWT),and the feature extraction is performed on the two-dimensional time–frequency image using the convolution layer at the front end of the network,and the extracted features are input into the capsule network.The capsule network converts the extracted features into vector neurons,and the dynamic routing algorithm is used to achieve feature transfer and output the results of fault diagnosis.Two different datasets are used to compare with other traditional deep learning models to verify the fault diagnosis capability of the method.The results show that the CCN has good diagnostic capability under different working conditions,even in the presence of noise and insufficient samples,compared to other models.This method contributes to the safe and reliable operation of mechanical equipment and is suitable for other rotating scenarios.展开更多
Most of the ecosystems are dominated by clonal species. The most unique feature of clonal plants is their capability for clonal integration (translocation of vital resources among connected ramets), implying that inte...Most of the ecosystems are dominated by clonal species. The most unique feature of clonal plants is their capability for clonal integration (translocation of vital resources among connected ramets), implying that integration may play an essential role in their success. However, a general effect of clonal integration on plant performance is lacking. We conducted a text review on the effects of clonal integration on different habitats and species. Overall, clonal integration increased performance of clonal plants in different habitats. However clonal integration has also some limitations under stressful environments. Benefits of clonal integration may lack somehow when environmental stress increases. But connected ramets placed in unfavorable patches benefited more from integration compared to severed ramet placed in nutrient rich patches. Climate change and temperature increase have positive effects on biomass of clonal species.展开更多
Sensor nodes cannot directly communicate with the distant unmanned aerial vehicle( UAV) for their low transmission power. Distributed collaborative beamforming from sensor nodes within a cluster is proposed to provide...Sensor nodes cannot directly communicate with the distant unmanned aerial vehicle( UAV) for their low transmission power. Distributed collaborative beamforming from sensor nodes within a cluster is proposed to provide high speed data transmission to the distant UAV. The bit error ratio( BER) closed-form expression of distributed collaborative beamforming transmission with mobile sensor nodes has been derived. Furthermore,based on the theoretical BER analysis and the numerical results,we have analyzed the impacts of nodes 'mobility,number of sensor nodes,transmission power and the elevation angle of UAV on the BER performance of collaborative beamforming. And we come to the following conclusions: the mobility of sensor nodes largely decreases the BER performance; when the position deviation radius is large,incensement in power cannot improve BER anymore; the size of cluster should be bigger than 10 for the purpose of achieving good BER performance in Rayleigh fading channel.展开更多
Lithium-ion batteries(LIBs)are crucial for the large-scale utilization of clean energy.However,because of the com-plexity and real-time nature of internal reactions,the mechanism of capacity decline in LIBs is still u...Lithium-ion batteries(LIBs)are crucial for the large-scale utilization of clean energy.However,because of the com-plexity and real-time nature of internal reactions,the mechanism of capacity decline in LIBs is still unclear.This has become a bottleneck restricting their promotion and application.Electrochemical impedance spectroscopy(EIS)contains rich electrochemical connotations and significant application prospects,and has attracted widespread atten-tion and research on efficient energy storage systems.Compared to traditional voltage and current data,the state-of-health(SOH)estimation model based on EIS has higher accuracy.This paper categorizes EIS measurement methods based on different principles,introduces the relationship between LIBs aging mechanism and SOH,and compares the advantages of different SOH estimation methods.After a detailed analysis of the latest technologies,a review is given.The insights of this review can deepen the understanding of the relationship between EIS and the aging effect mechanism of LIBs,and promote the development of new energy storage devices and evaluation methods.展开更多
We designed a low-filling-factor and polarization-sensitive superconducting nanowire single photon detector(SNSPD), which can achieve a high absorption efficiency and counting rate simultaneously. Numerical simulation...We designed a low-filling-factor and polarization-sensitive superconducting nanowire single photon detector(SNSPD), which can achieve a high absorption efficiency and counting rate simultaneously. Numerical simulations show that high absorption efficiency can be achieved by low-filling-factor SNSPDs with a silicon slot and silver reflector. The absorptance of the NbN nanowire for a transverse magnetic(TM) wave at the wavelength of 1550 nm can be 84.4% when the filling factor is only 16.5%, and the corresponding polarization extinction ratio(PER) is 562.9;the absorptance of the NbN nanowire for a transverse electric(TE) wave can be 67.0% when the filling factor is only 11.7%, and the PER is 7.4.展开更多
The Human immunodeficiency virus type 1(HIV-1) gp41 membrane proximal external region(MPER) is targeted by broadly neutralizing antibodies(e.g. 2F5, 4E10, Z13 e and m66.6), which makes this region a promising target f...The Human immunodeficiency virus type 1(HIV-1) gp41 membrane proximal external region(MPER) is targeted by broadly neutralizing antibodies(e.g. 2F5, 4E10, Z13 e and m66.6), which makes this region a promising target for vaccine design. One strategy to elicit neutralizing antibodies against the MPER epitope is to design peptide immunogens mimicking neutralization structures. To probe 2F5-like neutralizing antibodies, two yeast-displayed antibody libraries from peripheral blood mononuclear cells from a HIV-1 patient were screened against the 2F5 epitope peptide SP62. Two 2F5-like antibodies were identified that specifically recognized SP62. However,these antibodies only weakly neutralized HIV-1 primary isolates. The epitopes recognized by these two 2F5-like antibodies include not only the 2F5 epitope(amino acids(aa) 662–667 in the MPER)but also several other residues(aa 652–655) locating at the N-terminus in SP62. Experimental results suggest that residues of SP62 adjacent to the 2F5 epitope influence the response of broadly neutralizing 2F5-like antibodies in vaccination. Our findings may aid the design of vaccine immunogens and development of therapeutics against HIV-1 infection.展开更多
Smart grid construction is an important carrier and an effective way to promote the development of lowcarbon economy.Demand response(DR)is commonly regarded as an important core technology in smart grid field,and it r...Smart grid construction is an important carrier and an effective way to promote the development of lowcarbon economy.Demand response(DR)is commonly regarded as an important core technology in smart grid field,and it reflects the flexible and interactive features of the core business in smart electricity.It is the developing direction of automated demand response(ADR)technology,and its main features are the standardization of information exchange,together with the intelligence of decision-making and the automation of implementations.ADR technology can improve the efficiency of the whole power system and enhance the ability to accept new energy sources.This paper analyzes the role of demand response in improving efficiency and low-carbon energy saving power systems.The automated demand response system architecture is investigated,and the ADR roadmap of commercial/industrial and residential customer is proposed.The key technologies for ADR system are analyzed,including demand response strategy,information exchanging model,measurement and verification techniques,and multi-agent scheduling techniques.To ensure the interoperability between the grid side and the user side,the ADR business in smart grid user interface standards is concluded to support further demand side management project.展开更多
基金Science and Technology Planning Project of Inner Mongolia of China under contract number 2021GG0346.
文摘Fault diagnosis technology has been widely applied and is an important part of ensuring the safe operation of mechanical equipment.In response to the problem of frequent faults in rolling bearings,this paper designs a rolling bearing fault diagnosis method based on convolutional capsule network(CCN).More specifically,the original vibration signal is converted into a two-dimensional time–frequency image using continuous wavelet transform(CWT),and the feature extraction is performed on the two-dimensional time–frequency image using the convolution layer at the front end of the network,and the extracted features are input into the capsule network.The capsule network converts the extracted features into vector neurons,and the dynamic routing algorithm is used to achieve feature transfer and output the results of fault diagnosis.Two different datasets are used to compare with other traditional deep learning models to verify the fault diagnosis capability of the method.The results show that the CCN has good diagnostic capability under different working conditions,even in the presence of noise and insufficient samples,compared to other models.This method contributes to the safe and reliable operation of mechanical equipment and is suitable for other rotating scenarios.
文摘Most of the ecosystems are dominated by clonal species. The most unique feature of clonal plants is their capability for clonal integration (translocation of vital resources among connected ramets), implying that integration may play an essential role in their success. However, a general effect of clonal integration on plant performance is lacking. We conducted a text review on the effects of clonal integration on different habitats and species. Overall, clonal integration increased performance of clonal plants in different habitats. However clonal integration has also some limitations under stressful environments. Benefits of clonal integration may lack somehow when environmental stress increases. But connected ramets placed in unfavorable patches benefited more from integration compared to severed ramet placed in nutrient rich patches. Climate change and temperature increase have positive effects on biomass of clonal species.
文摘Sensor nodes cannot directly communicate with the distant unmanned aerial vehicle( UAV) for their low transmission power. Distributed collaborative beamforming from sensor nodes within a cluster is proposed to provide high speed data transmission to the distant UAV. The bit error ratio( BER) closed-form expression of distributed collaborative beamforming transmission with mobile sensor nodes has been derived. Furthermore,based on the theoretical BER analysis and the numerical results,we have analyzed the impacts of nodes 'mobility,number of sensor nodes,transmission power and the elevation angle of UAV on the BER performance of collaborative beamforming. And we come to the following conclusions: the mobility of sensor nodes largely decreases the BER performance; when the position deviation radius is large,incensement in power cannot improve BER anymore; the size of cluster should be bigger than 10 for the purpose of achieving good BER performance in Rayleigh fading channel.
基金supported by the Youth Fund of Shandong Province Natural Science Foundation(No.ZR2020QE212)Key Projects of Shandong Province Natural Science Foundation(No.ZR2020KF020)+2 种基金the Guangdong Provincial Key Lab of Green Chemical Product Technology(GC202111)Zhejiang Province Natural Science Foundation(No.LY22E070007)National Natural Science Foundation of China(No.52007170).
文摘Lithium-ion batteries(LIBs)are crucial for the large-scale utilization of clean energy.However,because of the com-plexity and real-time nature of internal reactions,the mechanism of capacity decline in LIBs is still unclear.This has become a bottleneck restricting their promotion and application.Electrochemical impedance spectroscopy(EIS)contains rich electrochemical connotations and significant application prospects,and has attracted widespread atten-tion and research on efficient energy storage systems.Compared to traditional voltage and current data,the state-of-health(SOH)estimation model based on EIS has higher accuracy.This paper categorizes EIS measurement methods based on different principles,introduces the relationship between LIBs aging mechanism and SOH,and compares the advantages of different SOH estimation methods.After a detailed analysis of the latest technologies,a review is given.The insights of this review can deepen the understanding of the relationship between EIS and the aging effect mechanism of LIBs,and promote the development of new energy storage devices and evaluation methods.
基金National Natural Science Foundation of China(NSFC)(61571060)Ministry of Science and Technology of the People’s Republic of China(MOST)(2016YFA0301300)
文摘We designed a low-filling-factor and polarization-sensitive superconducting nanowire single photon detector(SNSPD), which can achieve a high absorption efficiency and counting rate simultaneously. Numerical simulations show that high absorption efficiency can be achieved by low-filling-factor SNSPDs with a silicon slot and silver reflector. The absorptance of the NbN nanowire for a transverse magnetic(TM) wave at the wavelength of 1550 nm can be 84.4% when the filling factor is only 16.5%, and the corresponding polarization extinction ratio(PER) is 562.9;the absorptance of the NbN nanowire for a transverse electric(TE) wave can be 67.0% when the filling factor is only 11.7%, and the PER is 7.4.
基金supported by the Natural Science Foundation of Guangdong (No. 2015A030313741)the National Natural Science Foundation of China (No. 31440041)+2 种基金Shenzhen Peacock Innovation Plan Fund (No. KQCX20140520154115029)Shenzhen Knowledge Innovation Program (No. JCYJ20140901003939 026)Novo Nordisk A/S-Chinese Academy of Sciences Research Fund (No. NNCAS-2013-9)
文摘The Human immunodeficiency virus type 1(HIV-1) gp41 membrane proximal external region(MPER) is targeted by broadly neutralizing antibodies(e.g. 2F5, 4E10, Z13 e and m66.6), which makes this region a promising target for vaccine design. One strategy to elicit neutralizing antibodies against the MPER epitope is to design peptide immunogens mimicking neutralization structures. To probe 2F5-like neutralizing antibodies, two yeast-displayed antibody libraries from peripheral blood mononuclear cells from a HIV-1 patient were screened against the 2F5 epitope peptide SP62. Two 2F5-like antibodies were identified that specifically recognized SP62. However,these antibodies only weakly neutralized HIV-1 primary isolates. The epitopes recognized by these two 2F5-like antibodies include not only the 2F5 epitope(amino acids(aa) 662–667 in the MPER)but also several other residues(aa 652–655) locating at the N-terminus in SP62. Experimental results suggest that residues of SP62 adjacent to the 2F5 epitope influence the response of broadly neutralizing 2F5-like antibodies in vaccination. Our findings may aid the design of vaccine immunogens and development of therapeutics against HIV-1 infection.
基金This work was supported by the science and technology projects from State Grid Corporation.
文摘Smart grid construction is an important carrier and an effective way to promote the development of lowcarbon economy.Demand response(DR)is commonly regarded as an important core technology in smart grid field,and it reflects the flexible and interactive features of the core business in smart electricity.It is the developing direction of automated demand response(ADR)technology,and its main features are the standardization of information exchange,together with the intelligence of decision-making and the automation of implementations.ADR technology can improve the efficiency of the whole power system and enhance the ability to accept new energy sources.This paper analyzes the role of demand response in improving efficiency and low-carbon energy saving power systems.The automated demand response system architecture is investigated,and the ADR roadmap of commercial/industrial and residential customer is proposed.The key technologies for ADR system are analyzed,including demand response strategy,information exchanging model,measurement and verification techniques,and multi-agent scheduling techniques.To ensure the interoperability between the grid side and the user side,the ADR business in smart grid user interface standards is concluded to support further demand side management project.
