We numerically investigate a coupled-resonator structure consisting of a stub resonator and a nanodisk resonator using a two-dimensional finite element method. Simulation results show that plasmon-induced transparency...We numerically investigate a coupled-resonator structure consisting of a stub resonator and a nanodisk resonator using a two-dimensional finite element method. Simulation results show that plasmon-induced transparency (PIT) occurs in the transmission spectra, and the sharp asymmetric Fano lines increase the sensitivity to 1.4 ×10^3 nm/RIU. We also analyze the properties of the structure with different radii of the nanodisk and the length of the tooth cavity. Moreover, we find that the PIP only happens when the staggered system is around a fixed location with different separate distances, which is not similar to the previous researches. Our model may be important to photonic-integrated circuits and the sensitivity in sensors.展开更多
Recently,more and more supercapacitors(SCs)have been developed as AC line filter capacitors,which are generally named AC line filter electrochemical capacitors(FECs).Compared to traditional bulky aluminum electrolytic...Recently,more and more supercapacitors(SCs)have been developed as AC line filter capacitors,which are generally named AC line filter electrochemical capacitors(FECs).Compared to traditional bulky aluminum electrolytic capacitors(AECs),FECs have higher capacity and lower space occupancy,which makes them a strong competitor.However,different from the common SCs for energy storage,it is necessary to consider the frequency response of the SCs for AC line filtering,where the contradiction between frequency response and specific capacitance is a challenge.The researchers have proposed different solutions from the perspective of materials,morphology,and configuration for this challenge.Based on the above background,in this review,we briefly introduce the principle and parameters of AC line filter electrochemical capacitors.We systematically summarize the state-of-the-art progresses of FECs and discuss their possible application and development in the future.The development of FECs can greatly promote the planarization,integration,and miniaturization of filter capacitors,and provide a new solution for the utilization of green and unstable energy.展开更多
Compact supercapacitors(SCs)have attracted attention for their great potential to replace bulky aluminum electrolytic capacitors(AECs)in alternating current(AC)line filtering applications.Herein,the fabrication of a h...Compact supercapacitors(SCs)have attracted attention for their great potential to replace bulky aluminum electrolytic capacitors(AECs)in alternating current(AC)line filtering applications.Herein,the fabrication of a high-frequency SC is reported using Ketjen black(KB)nanoparticles doped with phosphorus(P)to achieve a high areal capacitance of up to 2.26 mF cm^(-2)along with a high-rate capability,with a phase angle of-80.2°at 120 Hz.The high performance of the phosphorus-doped KB(designated PKB)SC with a 6 M KOH aqueous electrolyte is associated with its increased surface wettability and additional capacitive sites provided by the P-doping.Density functional theory(DFT)calculations further indicate that the P-doping enhances the interactions between the electrolyte ions and the carbon surface,thus leading to an improved electrochemical performance.These results suggest that the P-doped carbonbased SC could be highly favored in replacing conventional AECs in various high-frequency electronic devices.展开更多
A real-time workbench able to reproduce the same behavior as an indoor network is in order. Such a tool will help researchers and industrials extend the smart grid technology indoors and have a better acknowledgment o...A real-time workbench able to reproduce the same behavior as an indoor network is in order. Such a tool will help researchers and industrials extend the smart grid technology indoors and have a better acknowledgment of Smart Grid systems interoperability. In order to develop such a tool many approaches should be studied to choose the most suitable one by comparing the models and the technologies. The considered hardware are the embedded systems and the selected approach is the statistical one. It appears that the FlR filter is the most pertinent approach.展开更多
The spatial matrix filter was designed and used for solving the problem to detect a weak target who was influenced by the strong nearby platform noise interference of the towed line array sonar. The MFP technology and...The spatial matrix filter was designed and used for solving the problem to detect a weak target who was influenced by the strong nearby platform noise interference of the towed line array sonar. The MFP technology and the DOA estimation technology were combined together by using the sound propagation characteristics of both target and interference. The spatial matrix filter with platform noise zero response constraint was designed by the near-field platform noise normal modes copy vectors and the far-field plane wave bearing vectors together. The optimal solution of the optimization problem for designing the spatial matrix filter was deduced directly, and it was simplified by the generalized singular value decomposition. The total response error to the plane wave bearing vectors and the total response to the platform noise copy vectors were given. The phenomena that strong interferences existed in the bearing course and blind areas existed after filtering were analyzed by the correlation between the plat- form noise copy vectors and the plane wave bearing vectors. It could be found from simulations that it has less blind area and higher detection ability by using the spatial matrix filtering technology.展开更多
A trust-region sequential quadratic programming (SQP) method is developed and analyzed for the solution of smooth equality constrained optimization problems. The trust-region SQP algorithm is based on filter line se...A trust-region sequential quadratic programming (SQP) method is developed and analyzed for the solution of smooth equality constrained optimization problems. The trust-region SQP algorithm is based on filter line search technique and a composite-step approach, which decomposes the overall step as sum of a vertical step and a horizontal step. The algorithm includes critical modifications of horizontal step computation. One orthogonal projective matrix of the Jacobian of constraint functions is employed in trust-region subproblems. The orthogonal projection gives the null space of the trans- position of the Jacobian of the constraint function. Theoretical analysis shows that the new algorithm retains the global convergence to the first-order critical points under rather general conditions. The preliminary numerical results are reported.展开更多
The effectiveness of using an Ensemble Square Root Filter(EnSRF) to assimilate real Doppler radar observations on convective scale is investigated by applying the technique to a case of squall line on 12July 2005 in...The effectiveness of using an Ensemble Square Root Filter(EnSRF) to assimilate real Doppler radar observations on convective scale is investigated by applying the technique to a case of squall line on 12July 2005 in midwest Shandong Province using the Weather Research and Forecasting(WRF) model.The experimental results show that:(1) The EnSRF system has the potential to initiate a squall line accurately by assimilation of real Doppler radar data.The convective-scale information has been added into the WRF model through radar data assimilation and thus the analyzed fields are improved noticeably.The model spin-up time has been shortened,and the precipitation forecast is improved accordingly.(2) Compared with the control run,the deterministic forecast initiated with the ensemble mean analysis of EnSRF produces more accurate prediction of microphysical fields.The predicted wind and thermal fields are reasonable and in accordance with the characteristics of convective storms.(3) The propagation direction of the squall line from the ensemble mean analysis is consistent with that of the observation,but the propagation speed is larger than the observed.The effective forecast period for this squall line is about 5-6 h,probably because of the nonlinear development of the convective storm.展开更多
Doppler global velocimetry (DGV) has already been shown to be an interesting technique capable of measuring the three components of velocity in a plane. A 1-component DGV system is currently under development at the...Doppler global velocimetry (DGV) has already been shown to be an interesting technique capable of measuring the three components of velocity in a plane. A 1-component DGV system is currently under development at the LMFA, using a stabilized continuous wave (CW) argon ion laser for ermssion, lne receiver Ieatures only one camera for both signal and reference images and incorporates a DEF1 system to adjust the incident laser light frequency and its transmission coefficient on the iodine cell absorption line. A description of the whole system is presented and a validation with measurements of axial velocities at several positions in a round free jet is proposed.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos 11374041 and 11404030the Fund of State Key Laboratory of Information Photonics and Optical Communications of Beijing University of Posts and Telecommunications of China
文摘We numerically investigate a coupled-resonator structure consisting of a stub resonator and a nanodisk resonator using a two-dimensional finite element method. Simulation results show that plasmon-induced transparency (PIT) occurs in the transmission spectra, and the sharp asymmetric Fano lines increase the sensitivity to 1.4 ×10^3 nm/RIU. We also analyze the properties of the structure with different radii of the nanodisk and the length of the tooth cavity. Moreover, we find that the PIP only happens when the staggered system is around a fixed location with different separate distances, which is not similar to the previous researches. Our model may be important to photonic-integrated circuits and the sensitivity in sensors.
基金financially supported by the National Natural Science Foundation of China(U20A20209)Zhejiang Provincial Key Research and Development Program(2021C01030)+7 种基金Zhejiang Provincial Natural Science Foundation of China(LD19E020001)Open Project of Laboratory for Biomedical Engineering of Ministry of Education,Zhejiang UniversityNational Key R@D Program of China(2016YFB0100100)National Natural Science Foundation of China(51872283,22075279,21805273)Liaoning Revitalization Talents Program(XLYC1807153)Dalian Innovation Support Plan for High Level Talents(2019RT09)Dalian National Laboratory For Clean Energy(DNL),CAS,DNL Cooperation Fund,CAS(DNL201912 and DNL201915)DICP(DICP ZZBS201708,DICP ZZBS201802,and DICP I2020032).
文摘Recently,more and more supercapacitors(SCs)have been developed as AC line filter capacitors,which are generally named AC line filter electrochemical capacitors(FECs).Compared to traditional bulky aluminum electrolytic capacitors(AECs),FECs have higher capacity and lower space occupancy,which makes them a strong competitor.However,different from the common SCs for energy storage,it is necessary to consider the frequency response of the SCs for AC line filtering,where the contradiction between frequency response and specific capacitance is a challenge.The researchers have proposed different solutions from the perspective of materials,morphology,and configuration for this challenge.Based on the above background,in this review,we briefly introduce the principle and parameters of AC line filter electrochemical capacitors.We systematically summarize the state-of-the-art progresses of FECs and discuss their possible application and development in the future.The development of FECs can greatly promote the planarization,integration,and miniaturization of filter capacitors,and provide a new solution for the utilization of green and unstable energy.
基金supported by grants from the National Research Foundation of Korea(NRF-2020R1A2C2008798)Korea University。
文摘Compact supercapacitors(SCs)have attracted attention for their great potential to replace bulky aluminum electrolytic capacitors(AECs)in alternating current(AC)line filtering applications.Herein,the fabrication of a high-frequency SC is reported using Ketjen black(KB)nanoparticles doped with phosphorus(P)to achieve a high areal capacitance of up to 2.26 mF cm^(-2)along with a high-rate capability,with a phase angle of-80.2°at 120 Hz.The high performance of the phosphorus-doped KB(designated PKB)SC with a 6 M KOH aqueous electrolyte is associated with its increased surface wettability and additional capacitive sites provided by the P-doping.Density functional theory(DFT)calculations further indicate that the P-doping enhances the interactions between the electrolyte ions and the carbon surface,thus leading to an improved electrochemical performance.These results suggest that the P-doped carbonbased SC could be highly favored in replacing conventional AECs in various high-frequency electronic devices.
文摘A real-time workbench able to reproduce the same behavior as an indoor network is in order. Such a tool will help researchers and industrials extend the smart grid technology indoors and have a better acknowledgment of Smart Grid systems interoperability. In order to develop such a tool many approaches should be studied to choose the most suitable one by comparing the models and the technologies. The considered hardware are the embedded systems and the selected approach is the statistical one. It appears that the FlR filter is the most pertinent approach.
基金supported by the National Natural Science Foundation of China(60532040,11374001)
文摘The spatial matrix filter was designed and used for solving the problem to detect a weak target who was influenced by the strong nearby platform noise interference of the towed line array sonar. The MFP technology and the DOA estimation technology were combined together by using the sound propagation characteristics of both target and interference. The spatial matrix filter with platform noise zero response constraint was designed by the near-field platform noise normal modes copy vectors and the far-field plane wave bearing vectors together. The optimal solution of the optimization problem for designing the spatial matrix filter was deduced directly, and it was simplified by the generalized singular value decomposition. The total response error to the plane wave bearing vectors and the total response to the platform noise copy vectors were given. The phenomena that strong interferences existed in the bearing course and blind areas existed after filtering were analyzed by the correlation between the plat- form noise copy vectors and the plane wave bearing vectors. It could be found from simulations that it has less blind area and higher detection ability by using the spatial matrix filtering technology.
基金Supported by National Natural Science Foundation of China(Grant Nos.11671122 and 11371253)Key Scientific Research Project for Colleges and Universities in He’nan Province(Grant No.15A110031)+2 种基金Key Scientific and Technological Project of He’nan Province(Grant No.162102210069)Natural Science Foundation of He’nan Normal University(Grant No.2014QK04)Ph.D. Research Foundation of He’nan Normal University(Grant Nos.QD13041 and QD14155)
文摘A trust-region sequential quadratic programming (SQP) method is developed and analyzed for the solution of smooth equality constrained optimization problems. The trust-region SQP algorithm is based on filter line search technique and a composite-step approach, which decomposes the overall step as sum of a vertical step and a horizontal step. The algorithm includes critical modifications of horizontal step computation. One orthogonal projective matrix of the Jacobian of constraint functions is employed in trust-region subproblems. The orthogonal projection gives the null space of the trans- position of the Jacobian of the constraint function. Theoretical analysis shows that the new algorithm retains the global convergence to the first-order critical points under rather general conditions. The preliminary numerical results are reported.
基金Supported by the National Natural Science Foundation of China(41105067)National High Technology Research and Development Program of China(2013AA09A506-5)Special Scientific Reserch Fund of Marin Public Welfare Profession of China(201305032-2)
文摘The effectiveness of using an Ensemble Square Root Filter(EnSRF) to assimilate real Doppler radar observations on convective scale is investigated by applying the technique to a case of squall line on 12July 2005 in midwest Shandong Province using the Weather Research and Forecasting(WRF) model.The experimental results show that:(1) The EnSRF system has the potential to initiate a squall line accurately by assimilation of real Doppler radar data.The convective-scale information has been added into the WRF model through radar data assimilation and thus the analyzed fields are improved noticeably.The model spin-up time has been shortened,and the precipitation forecast is improved accordingly.(2) Compared with the control run,the deterministic forecast initiated with the ensemble mean analysis of EnSRF produces more accurate prediction of microphysical fields.The predicted wind and thermal fields are reasonable and in accordance with the characteristics of convective storms.(3) The propagation direction of the squall line from the ensemble mean analysis is consistent with that of the observation,but the propagation speed is larger than the observed.The effective forecast period for this squall line is about 5-6 h,probably because of the nonlinear development of the convective storm.
基金the CIRT (Consortium Indus trie Recherche en Turbomachines) which is supporting this workmore particularly at the LMFA, Alain Ef fernelli for building many elements of the receiver, Gil bert Halter for helping in the collimation processAndre Vouillarmet for his advice in this project.
文摘Doppler global velocimetry (DGV) has already been shown to be an interesting technique capable of measuring the three components of velocity in a plane. A 1-component DGV system is currently under development at the LMFA, using a stabilized continuous wave (CW) argon ion laser for ermssion, lne receiver Ieatures only one camera for both signal and reference images and incorporates a DEF1 system to adjust the incident laser light frequency and its transmission coefficient on the iodine cell absorption line. A description of the whole system is presented and a validation with measurements of axial velocities at several positions in a round free jet is proposed.