In this paper,three tuning methods of the integer order proportional integral derivative(IOPID)controller,the fuzzy proportional integral derivative(FPID)controller and the fractional order proportional integral deriv...In this paper,three tuning methods of the integer order proportional integral derivative(IOPID)controller,the fuzzy proportional integral derivative(FPID)controller and the fractional order proportional integral derivative(FOPID)controller for high order system are presented respectively.Both IOPID controller and FOPID controller designed by the two tuning methods can satisfy all the three specifications proposed,which can guarantee the desired control performance and the robustness of the high order system to the loop gain variations.From the simulation results,the three controllers meet the dynamic performance requirements of high order system.Moreover,the FOPID controller,with the shortest overshoot and adjustment time,outperforms the IOPID controller and the FPID controller for the high order system.展开更多
This paper deals with the study of fractional order system tuning method based on Factional Order Proportional Integral Derivative( FOPID) controller in allusion to the nonlinear characteristics and fractional order m...This paper deals with the study of fractional order system tuning method based on Factional Order Proportional Integral Derivative( FOPID) controller in allusion to the nonlinear characteristics and fractional order mathematical model of bioengineering systems. The main contents include the design of FOPID controller and the simulation for bioengineering systems. The simulation results show that the tuning method of fractional order system based on the FOPID controller outperforms the fractional order system based on Fractional Order Proportional Integral( FOPI) controller. As it can enhance control character and improve the robustness of the system.展开更多
The method of moving target detection based on subimage cancellation for single-antenna airborne SAR is presented. First the subimage is obtained through frequency processing is pointed out. The imaging difference of ...The method of moving target detection based on subimage cancellation for single-antenna airborne SAR is presented. First the subimage is obtained through frequency processing is pointed out. The imaging difference of a stationary objects and moving object in the subimage based on the frequency division is analyzed from the fundamental principle. Then the developed method combines the shear averaging algorithm to focus on the moving target in the subimage, after the clutter suppression and the focusing position in each subimage is obtained. Next the observation model and the relative movement of the moving targets between the subimages estimate the moving targets. The theoretical analysis and simulation results demonstrate that the method is effective and can not only detect the moving targets, but also estimate their motion parameters precisely.展开更多
In order to undertake theory analysis in the application area of switching,frequency and power devices,an analytical model for capacitance-voltage (C-V) characteristics of ion-implanted 4H silicon carbide (SiC) Schott...In order to undertake theory analysis in the application area of switching,frequency and power devices,an analytical model for capacitance-voltage (C-V) characteristics of ion-implanted 4H silicon carbide (SiC) Schottky barrier diodes (SBDs) was investigated.This model was established by considering the effects of incomplete ionization of nitrogen in 4H-SiC,the Poole-Frenkel on the ionization energy,and the ion-implanted nitrogen donor profiles.The simulation process is discussed in detail for two multiple nitrogen ion-implanted 4H-SiC SBDs (three and four fold ion-implantations) designed and fabricated in the experiments using this model at different activation rates.An agreement between the modeled C-V curves and the measured results for two ion-implanted 4H-SiC SBDs fabricated is shown.This capacitance model has the potential to be used to simulate and design ion-implanted SiC devices concerned in the future.展开更多
In the video-based surveillance application, moving shadows can affect the correct localization and detection of moving objects. This paper aims to present a method for shadow detection and suppression used for moving...In the video-based surveillance application, moving shadows can affect the correct localization and detection of moving objects. This paper aims to present a method for shadow detection and suppression used for moving visual object detection. The major novelty of the shadow suppression is the integration of several features including photometric invariant color feature, motion edge feature, and spatial feature etc. By modifying process for false shadow detected, the averaging detection rate of moving object reaches above 90% in the test of Hall-Monitor sequence.展开更多
Ring signature and proxy signature are of vital importance to secure electronic commerce. Recently, the bilinear pairing such as Well pairing or Tate pairing on elliptic curves and hyperelliptic curves is playing an i...Ring signature and proxy signature are of vital importance to secure electronic commerce. Recently, the bilinear pairing such as Well pairing or Tate pairing on elliptic curves and hyperelliptic curves is playing an important role in security solutions. Several ID-based signature schemes have been put forward, many of which are based on bilinear pairings. In key management and moderate security demand scenarios, ID-based public key cryptosystem is more preferable than other public key infrastructure based systems. In this paper, an improved ID-based proxy ring signature scheme from bilinear pairings is proposed which combines the advantages of proxy signature and of ring signatures. Our scheme can guarantee the profits of the proxy signer via preventing the original signer form generating the proxy ring signature. Furthermore, bilinear pairings are introduced to minimize the computation overhead and to improve the related performance of our scheme. In contrast with Zhang's scheme, our scheme is a computational efficiency improvement for signature verification because the computational cost of bilinear pairings required is reduced from O(n) to O( 1 ). In addition, the proxy ring signature presented in this paper can perfectly satisfy all the security requirements of proxy ring signature, i. e. signer-ambiguity, non-forgeability, verification, non-deniability and distinguishability.展开更多
To strike a tradeoff between the security and the consumption of energy,computing and communication resources in the nodes,this paper presents an efficient authentication scheme based on one-way key chain for sensor n...To strike a tradeoff between the security and the consumption of energy,computing and communication resources in the nodes,this paper presents an efficient authentication scheme based on one-way key chain for sensor network. The scheme can provide immediate authentication to fulfill the latency and the storage requirements and defends against various attacks such as replay,impersonation and denial of service. Meanwhile,our scheme possesses low overhead and scalability to large networks. Furthermore,the simple related protocols or algorithms in the scheme and inexpensive public-key operation required in view of resource-starved sensor nodes minimize the storage,computation and communication overhead,and improve the efficiency of our scheme. In addition,the proposed scheme also supports source authentication without precluding in-network processing and passive participation.展开更多
We here present an ongoing research project about an integrated real time mobility assistant, which has been developed for the call “Personal Integrated Mobility” of the EU framework program. The assistant is aimed ...We here present an ongoing research project about an integrated real time mobility assistant, which has been developed for the call “Personal Integrated Mobility” of the EU framework program. The assistant is aimed to support personal mobility in a near future scenario, where green, shared or public transports are replacing the current private, carbon transportation system. The assistant handles itineraries, which are based on goals of time, energy/pollution and cost, and supports users both before and during the trip. The service will gather and interpret any relevant source of information on transport resources and their availability. Information includes user generated content and social data. Given the globalization of users and the hourly peaks of mobility, the assistant is a cloud service, which integrates existing technologies;however a global extension requires a federation of clouds and, above all, the interpretation and validation of social data. These can be considered major research challenges.展开更多
基金Sponsored by the Foundation of Jilin Educational Committee(Grant No.22201-2221010195)
文摘In this paper,three tuning methods of the integer order proportional integral derivative(IOPID)controller,the fuzzy proportional integral derivative(FPID)controller and the fractional order proportional integral derivative(FOPID)controller for high order system are presented respectively.Both IOPID controller and FOPID controller designed by the two tuning methods can satisfy all the three specifications proposed,which can guarantee the desired control performance and the robustness of the high order system to the loop gain variations.From the simulation results,the three controllers meet the dynamic performance requirements of high order system.Moreover,the FOPID controller,with the shortest overshoot and adjustment time,outperforms the IOPID controller and the FPID controller for the high order system.
文摘This paper deals with the study of fractional order system tuning method based on Factional Order Proportional Integral Derivative( FOPID) controller in allusion to the nonlinear characteristics and fractional order mathematical model of bioengineering systems. The main contents include the design of FOPID controller and the simulation for bioengineering systems. The simulation results show that the tuning method of fractional order system based on the FOPID controller outperforms the fractional order system based on Fractional Order Proportional Integral( FOPI) controller. As it can enhance control character and improve the robustness of the system.
文摘The method of moving target detection based on subimage cancellation for single-antenna airborne SAR is presented. First the subimage is obtained through frequency processing is pointed out. The imaging difference of a stationary objects and moving object in the subimage based on the frequency division is analyzed from the fundamental principle. Then the developed method combines the shear averaging algorithm to focus on the moving target in the subimage, after the clutter suppression and the focusing position in each subimage is obtained. Next the observation model and the relative movement of the moving targets between the subimages estimate the moving targets. The theoretical analysis and simulation results demonstrate that the method is effective and can not only detect the moving targets, but also estimate their motion parameters precisely.
文摘In order to undertake theory analysis in the application area of switching,frequency and power devices,an analytical model for capacitance-voltage (C-V) characteristics of ion-implanted 4H silicon carbide (SiC) Schottky barrier diodes (SBDs) was investigated.This model was established by considering the effects of incomplete ionization of nitrogen in 4H-SiC,the Poole-Frenkel on the ionization energy,and the ion-implanted nitrogen donor profiles.The simulation process is discussed in detail for two multiple nitrogen ion-implanted 4H-SiC SBDs (three and four fold ion-implantations) designed and fabricated in the experiments using this model at different activation rates.An agreement between the modeled C-V curves and the measured results for two ion-implanted 4H-SiC SBDs fabricated is shown.This capacitance model has the potential to be used to simulate and design ion-implanted SiC devices concerned in the future.
文摘In the video-based surveillance application, moving shadows can affect the correct localization and detection of moving objects. This paper aims to present a method for shadow detection and suppression used for moving visual object detection. The major novelty of the shadow suppression is the integration of several features including photometric invariant color feature, motion edge feature, and spatial feature etc. By modifying process for false shadow detected, the averaging detection rate of moving object reaches above 90% in the test of Hall-Monitor sequence.
基金Sponsored by the National Natural Science Foundation of China(Grant No.90104033).
文摘Ring signature and proxy signature are of vital importance to secure electronic commerce. Recently, the bilinear pairing such as Well pairing or Tate pairing on elliptic curves and hyperelliptic curves is playing an important role in security solutions. Several ID-based signature schemes have been put forward, many of which are based on bilinear pairings. In key management and moderate security demand scenarios, ID-based public key cryptosystem is more preferable than other public key infrastructure based systems. In this paper, an improved ID-based proxy ring signature scheme from bilinear pairings is proposed which combines the advantages of proxy signature and of ring signatures. Our scheme can guarantee the profits of the proxy signer via preventing the original signer form generating the proxy ring signature. Furthermore, bilinear pairings are introduced to minimize the computation overhead and to improve the related performance of our scheme. In contrast with Zhang's scheme, our scheme is a computational efficiency improvement for signature verification because the computational cost of bilinear pairings required is reduced from O(n) to O( 1 ). In addition, the proxy ring signature presented in this paper can perfectly satisfy all the security requirements of proxy ring signature, i. e. signer-ambiguity, non-forgeability, verification, non-deniability and distinguishability.
基金the National Natural Science Foundation of China (Grant No. 60202005).
文摘To strike a tradeoff between the security and the consumption of energy,computing and communication resources in the nodes,this paper presents an efficient authentication scheme based on one-way key chain for sensor network. The scheme can provide immediate authentication to fulfill the latency and the storage requirements and defends against various attacks such as replay,impersonation and denial of service. Meanwhile,our scheme possesses low overhead and scalability to large networks. Furthermore,the simple related protocols or algorithms in the scheme and inexpensive public-key operation required in view of resource-starved sensor nodes minimize the storage,computation and communication overhead,and improve the efficiency of our scheme. In addition,the proposed scheme also supports source authentication without precluding in-network processing and passive participation.
文摘We here present an ongoing research project about an integrated real time mobility assistant, which has been developed for the call “Personal Integrated Mobility” of the EU framework program. The assistant is aimed to support personal mobility in a near future scenario, where green, shared or public transports are replacing the current private, carbon transportation system. The assistant handles itineraries, which are based on goals of time, energy/pollution and cost, and supports users both before and during the trip. The service will gather and interpret any relevant source of information on transport resources and their availability. Information includes user generated content and social data. Given the globalization of users and the hourly peaks of mobility, the assistant is a cloud service, which integrates existing technologies;however a global extension requires a federation of clouds and, above all, the interpretation and validation of social data. These can be considered major research challenges.