A security issue with multi-sensor unmanned aerial vehicle(UAV)cyber physical systems(CPS)from the viewpoint of a false data injection(FDI)attacker is investigated in this paper.The FDI attacker can employ attacks on ...A security issue with multi-sensor unmanned aerial vehicle(UAV)cyber physical systems(CPS)from the viewpoint of a false data injection(FDI)attacker is investigated in this paper.The FDI attacker can employ attacks on feedback and feed-forward channels simultaneously with limited resource.The attacker aims at degrading the UAV CPS's estimation performance to the max while keeping stealthiness characterized by the Kullback-Leibler(K-L)divergence.The attacker is resource limited which can only attack part of sensors,and the attacked sensor as well as specific forms of attack signals at each instant should be considered by the attacker.Also,the sensor selection principle is investigated with respect to time invariant attack covariances.Additionally,the optimal switching attack strategies in regard to time variant attack covariances are modeled as a multi-agent Markov decision process(MDP)with hybrid discrete-continuous action space.Then,the multi-agent MDP is solved by utilizing the deep Multi-agent parameterized Q-networks(MAPQN)method.Ultimately,a quadrotor near hover system is used to validate the effectiveness of the results in the simulation section.展开更多
24 September 2013, Shenzhen--ZTE today announced the release of the BigMatrix 9900 series of data center switches, the world＇ s largest-capacity data center switches. The BigMatrix 9900 product family comprises data...24 September 2013, Shenzhen--ZTE today announced the release of the BigMatrix 9900 series of data center switches, the world＇ s largest-capacity data center switches. The BigMatrix 9900 product family comprises data switches with the largest capacity in the world. The switches are designed large cloud computing and big data scenarios and allow for higher-density deployment in data centers. Each single slot can support up to 144 10G ports, 36 40G ports, or 12 IOOG ports. The Big Matrix 9900 series comprises four switch models-9916, 9912, 9908, and 9904-each of which supports a maximum switching capacity of 84.48 Tbps.展开更多
Today’s network industry needs highly qualified engineers to understand, configure, develop and upgrade switches that can build scalable high performance and ultra-low latency networks. This paper describes a new net...Today’s network industry needs highly qualified engineers to understand, configure, develop and upgrade switches that can build scalable high performance and ultra-low latency networks. This paper describes a new networking laboratory that has been set up to provide hands-on experience on datacenter network switches, such as ARISTA, programming and monitoring the traffic. This paper explains the networking laboratory coursework that students carry out during the course of a semester. The laboratory consists of six hands on experiments on the latest datacenter switches from Arista Networks, two programming assignments that teaches some of the protocols used at data link layer and routing protocols used at the network layer of OSI reference model. The final two laboratory experiments use the Wireshark software tool for traffic monitoring and peeking into details of some of the protocols in TCP/IP such as ARP protocol, Ethernet and so forth. The coursework details include the switch basics, switch hardware, Extensible Operating System (EOS), configuration of Link Aggregation Control Protocol, Multi-chassis Link Aggregation Protocol, Access Control Lists, and Open Short Path First version 2 on Arista switches 7050T-64 and 7048T-4S. The programming tasks cover High-level Data Link Control (HDLC) and Routing Algorithms.展开更多
As investigated by 3GPP,support of UPF(user plane function)onboard satellite can reduce the latency of communications via satellite,and then it becomes a key enhancement in 5G network integrating with satellite commun...As investigated by 3GPP,support of UPF(user plane function)onboard satellite can reduce the latency of communications via satellite,and then it becomes a key enhancement in 5G network integrating with satellite communication.However,current 5G system cannot support UPF onboard LEO(low earth orbit)satellites,as it would face challenges like UPF mobility handling,synchronization between mobile network and satellite network,and condition of activating local data switching.To solve such challenges,this paper proposes a solution to support UPF onboard LEO satellite,which consists of enhanced network architecture,I-UPF(intermediate UPF)based local data switching scheme and communication latency based data path selection.We subsequently develop analytic models for performance evaluation and conduct simulations using the constellation configuration of iridium II.The simulation results show that the data switching via I-UPF onboard LEO satellite can reduce E2E(end to end)packet delivery latency and E2E packet loss ratio significantly compared with that of routing the data back to 5GC on the ground.The proposed scheme yet has increased signaling cost for handling UPF mobility.els,compared with existing similar companding algorithms.展开更多
传统移相控制下,无线电能传输(Wireles power transfer,WPT)系统输出功率宽范围调节时逆变器开关管易丢失零电压开关(Zero voltage switching,ZVS)状态,导致逆变器切换损耗增大甚至损坏。阶跃脉冲调制(Stepped Pulse Modulation)是一种...传统移相控制下,无线电能传输(Wireles power transfer,WPT)系统输出功率宽范围调节时逆变器开关管易丢失零电压开关(Zero voltage switching,ZVS)状态,导致逆变器切换损耗增大甚至损坏。阶跃脉冲调制(Stepped Pulse Modulation)是一种低输出纹波调制方法,可实现宽负载范围内的ZVS运行。但是,该调制方法包含有限状态机等环节,不易采用传统的机理建模访求进行建模,给控制器设计带来困难。在Simulink电路的基础上,基于数据驱动方法辨识了无线电能传输在阶跃脉冲调制下传递函数模型,并基于该模型设计内模控制器。实验表明,基于Simulink电路仿真方法获取采样数据,能够有效解决实物实验在某些场景下难以获取实验数据的难题,获得满意的辨识模型。同时,基于辨识模型设计的内模控制器,能够精确估计不同控制参数下的系统控制性能,满足了阶跃脉冲调制无线电能传输输出电压闭环控制的性能需求。展开更多
This paper deals with the problem of non-fragile linear parameter-varying（LPV） H_∞ control for morphing aircraft with asynchronous switching.The switched LPV model of morphing aircraft is established by Jacobian li...This paper deals with the problem of non-fragile linear parameter-varying（LPV） H_∞ control for morphing aircraft with asynchronous switching.The switched LPV model of morphing aircraft is established by Jacobian linearization approach according to the nonlinear model.The data missing is taken into account in the link from sensors to controllers and the link from controllers to actuators,which satisfies Bernoulli distribution.The non-fragile switched LPV controllers are constructed with consideration of the uncertainties of controllers and asynchronous switching phenomenon.The parameter-dependent Lyapunov functional method and mode-dependent average dwell time（MDADT） method are combined to guarantee the stability and prescribed performance of the system.The sufficient conditions on the solvability of the problem are derived in the form of linear matrix inequalities（LMI）.In order to achieve higher efficiency of the designing process,an algorithm is applied to divide the whole set into subsets automatically.Simulation results are provided to verify the effectiveness and superiority of the method in the paper.展开更多
Traffic modeling is a key step in several intelligent transportation systems（ITS） applications. This paper regards the traffic modeling through the enhancement of the cell transmission model. It considers the traffi...Traffic modeling is a key step in several intelligent transportation systems（ITS） applications. This paper regards the traffic modeling through the enhancement of the cell transmission model. It considers the traffic flow as a hybrid dynamic system and proposes a piecewise switched linear traffic model. The latter allows an accurate modeling of the traffic flow in a given section by considering its geometry. On the other hand, the piecewise switched linear traffic model handles more than one congestion wave and has the advantage to be modular. The measurements at upstream and downstream boundaries are also used in this model in order to decouple the traffic flow dynamics of successive road portions. Finally, real magnetic sensor data, provided by the performance measurement system on a portion of the Californian SR60-E highway are used to validate the proposed model.展开更多
In the data encryption standard （DES） algorithm, there exist several bit-switching functions, including permutations, expansion, and permuted choices. They are generally presented in the form of matrixes and realize...In the data encryption standard （DES） algorithm, there exist several bit-switching functions, including permutations, expansion, and permuted choices. They are generally presented in the form of matrixes and realized by using table look-up technique in the implementation of the cryptosystem. This paper presents explicit formulas for the initial permutation IP, its inverse IP-1 , the expansion function E, and the permuted choice PC_1. It also gives the program realizations of these functions in C＋＋ applying these formulas. With the advantage of the omission of the storage space for these matrixes and the tedious inputs of tables in the implementations of DES, our experimental results shows that the explicit formulas are useful in some situations, such as wireless sensor networks where the memory capacity is limited, especially when the size of file for encrypting is not too large, preferably smaller than 256KB.展开更多
A hybrid switching node structure with light and microwave links is proposed, which is applicable to the future data relay satellite systems, aiming at the development trend of coexistence of light- link and microwave...A hybrid switching node structure with light and microwave links is proposed, which is applicable to the future data relay satellite systems, aiming at the development trend of coexistence of light- link and microwave-link in the future. An experimental system for the light and microwave hybrid switching node based on wavelength selective optical switches (WSS) and optical transceiver modules, is established. It is shown by our experiment that this hybrid switching node can realize the dynamic bandwidth allocation and wavelength routing while the bit error rate of light link is less than 10?12, which provides a method for solving the hybrid switching problem of light-link and microwave-link on the future data relay satellite systems.展开更多
Telecom sectors generally operate at negative voltages to reduce the effect of corrosion caused in the metallic wire due to electrochemical reaction while communicating signals. To feed those lines and to have an effe...Telecom sectors generally operate at negative voltages to reduce the effect of corrosion caused in the metallic wire due to electrochemical reaction while communicating signals. To feed those lines and to have an effective digital data transmission, a power electronic converter referred as Modified Negative Luo Converter (MNLC) is proposed in this paper. MNLC is a high gain converter in which the output voltage increases in geometric progression. This paper portrays a novel concept of a 50 Hz pulse data transmission through RLCG (Resistance-inductance-capacitance with a shunt conductance) transmission line using MNLC. Signal frequency of 50 Hz to be transmitted is anded with a high frequency pulse that charges and discharges MNLC and produces the boosted negative output voltage. The boosted output is again transmitted through the RLCG transmission line from which 50 Hz data pulse is retrieved at the output of the transmission line by comparing with a comparator signal. This sort of MNLC aided data transmission not only introduces less loss in its transmitted data but also overcomes various health hazards of conventional radio frequency (RF) communication. This technique also proves that any data bit stream can be transmitted and retrieved using the proposed high gain DC-DC converter. The simulation model of the proposed system is implemented in MATLAB for various switching frequencies with its prototype of the converter developed and the results are verified.展开更多
Power generation becomes the need of developed, developing and under developed countries to meet their increasing power requirements. When affordability increases their requirement of power increases, this happens whe...Power generation becomes the need of developed, developing and under developed countries to meet their increasing power requirements. When affordability increases their requirement of power increases, this happens when increased per capita consumption. The existing power scenario states that highest power is produced using firing of coals called thermal energy. A high efficiency Switched Reluctance Generator (SRG) based high frequency switching scheme to enhance the output for grid connectivity is designed, fabricated and evaluated. This proposed method generates the output for the low wind speed. It provides output at low speed because of multi-level DC-DC converter and storage system. It is an efficient solution for low wind power generation. The real time readings and results are discussed.展开更多
文摘A security issue with multi-sensor unmanned aerial vehicle(UAV)cyber physical systems(CPS)from the viewpoint of a false data injection(FDI)attacker is investigated in this paper.The FDI attacker can employ attacks on feedback and feed-forward channels simultaneously with limited resource.The attacker aims at degrading the UAV CPS's estimation performance to the max while keeping stealthiness characterized by the Kullback-Leibler(K-L)divergence.The attacker is resource limited which can only attack part of sensors,and the attacked sensor as well as specific forms of attack signals at each instant should be considered by the attacker.Also,the sensor selection principle is investigated with respect to time invariant attack covariances.Additionally,the optimal switching attack strategies in regard to time variant attack covariances are modeled as a multi-agent Markov decision process(MDP)with hybrid discrete-continuous action space.Then,the multi-agent MDP is solved by utilizing the deep Multi-agent parameterized Q-networks(MAPQN)method.Ultimately,a quadrotor near hover system is used to validate the effectiveness of the results in the simulation section.
文摘24 September 2013, Shenzhen--ZTE today announced the release of the BigMatrix 9900 series of data center switches, the world＇ s largest-capacity data center switches. The BigMatrix 9900 product family comprises data switches with the largest capacity in the world. The switches are designed large cloud computing and big data scenarios and allow for higher-density deployment in data centers. Each single slot can support up to 144 10G ports, 36 40G ports, or 12 IOOG ports. The Big Matrix 9900 series comprises four switch models-9916, 9912, 9908, and 9904-each of which supports a maximum switching capacity of 84.48 Tbps.
文摘Today’s network industry needs highly qualified engineers to understand, configure, develop and upgrade switches that can build scalable high performance and ultra-low latency networks. This paper describes a new networking laboratory that has been set up to provide hands-on experience on datacenter network switches, such as ARISTA, programming and monitoring the traffic. This paper explains the networking laboratory coursework that students carry out during the course of a semester. The laboratory consists of six hands on experiments on the latest datacenter switches from Arista Networks, two programming assignments that teaches some of the protocols used at data link layer and routing protocols used at the network layer of OSI reference model. The final two laboratory experiments use the Wireshark software tool for traffic monitoring and peeking into details of some of the protocols in TCP/IP such as ARP protocol, Ethernet and so forth. The coursework details include the switch basics, switch hardware, Extensible Operating System (EOS), configuration of Link Aggregation Control Protocol, Multi-chassis Link Aggregation Protocol, Access Control Lists, and Open Short Path First version 2 on Arista switches 7050T-64 and 7048T-4S. The programming tasks cover High-level Data Link Control (HDLC) and Routing Algorithms.
基金supported by the national key research and development program of China under Grant 2020YFB1807901the National Science Foundation Project in China under grant 61931005.
文摘As investigated by 3GPP,support of UPF(user plane function)onboard satellite can reduce the latency of communications via satellite,and then it becomes a key enhancement in 5G network integrating with satellite communication.However,current 5G system cannot support UPF onboard LEO(low earth orbit)satellites,as it would face challenges like UPF mobility handling,synchronization between mobile network and satellite network,and condition of activating local data switching.To solve such challenges,this paper proposes a solution to support UPF onboard LEO satellite,which consists of enhanced network architecture,I-UPF(intermediate UPF)based local data switching scheme and communication latency based data path selection.We subsequently develop analytic models for performance evaluation and conduct simulations using the constellation configuration of iridium II.The simulation results show that the data switching via I-UPF onboard LEO satellite can reduce E2E(end to end)packet delivery latency and E2E packet loss ratio significantly compared with that of routing the data back to 5GC on the ground.The proposed scheme yet has increased signaling cost for handling UPF mobility.els,compared with existing similar companding algorithms.
文摘传统移相控制下,无线电能传输(Wireles power transfer,WPT)系统输出功率宽范围调节时逆变器开关管易丢失零电压开关(Zero voltage switching,ZVS)状态,导致逆变器切换损耗增大甚至损坏。阶跃脉冲调制(Stepped Pulse Modulation)是一种低输出纹波调制方法,可实现宽负载范围内的ZVS运行。但是,该调制方法包含有限状态机等环节,不易采用传统的机理建模访求进行建模,给控制器设计带来困难。在Simulink电路的基础上,基于数据驱动方法辨识了无线电能传输在阶跃脉冲调制下传递函数模型,并基于该模型设计内模控制器。实验表明,基于Simulink电路仿真方法获取采样数据,能够有效解决实物实验在某些场景下难以获取实验数据的难题,获得满意的辨识模型。同时,基于辨识模型设计的内模控制器,能够精确估计不同控制参数下的系统控制性能,满足了阶跃脉冲调制无线电能传输输出电压闭环控制的性能需求。
基金supported by the National Natural Science Foundation of China(Nos.61374012,61273083 and 61403028)
文摘This paper deals with the problem of non-fragile linear parameter-varying（LPV） H_∞ control for morphing aircraft with asynchronous switching.The switched LPV model of morphing aircraft is established by Jacobian linearization approach according to the nonlinear model.The data missing is taken into account in the link from sensors to controllers and the link from controllers to actuators,which satisfies Bernoulli distribution.The non-fragile switched LPV controllers are constructed with consideration of the uncertainties of controllers and asynchronous switching phenomenon.The parameter-dependent Lyapunov functional method and mode-dependent average dwell time（MDADT） method are combined to guarantee the stability and prescribed performance of the system.The sufficient conditions on the solvability of the problem are derived in the form of linear matrix inequalities（LMI）.In order to achieve higher efficiency of the designing process,an algorithm is applied to divide the whole set into subsets automatically.Simulation results are provided to verify the effectiveness and superiority of the method in the paper.
文摘Traffic modeling is a key step in several intelligent transportation systems（ITS） applications. This paper regards the traffic modeling through the enhancement of the cell transmission model. It considers the traffic flow as a hybrid dynamic system and proposes a piecewise switched linear traffic model. The latter allows an accurate modeling of the traffic flow in a given section by considering its geometry. On the other hand, the piecewise switched linear traffic model handles more than one congestion wave and has the advantage to be modular. The measurements at upstream and downstream boundaries are also used in this model in order to decouple the traffic flow dynamics of successive road portions. Finally, real magnetic sensor data, provided by the performance measurement system on a portion of the Californian SR60-E highway are used to validate the proposed model.
基金Supported by the National Natural Science Foundation of China (61272045)Natural Science Foundation of Outstanding Youth Team Project of Zhejiang Province (R1090138)Project of the State Key Laboratory of Information Security (Institute of Information Engineering, Chinese Academy of Sciences, Beijing)
文摘In the data encryption standard （DES） algorithm, there exist several bit-switching functions, including permutations, expansion, and permuted choices. They are generally presented in the form of matrixes and realized by using table look-up technique in the implementation of the cryptosystem. This paper presents explicit formulas for the initial permutation IP, its inverse IP-1 , the expansion function E, and the permuted choice PC_1. It also gives the program realizations of these functions in C＋＋ applying these formulas. With the advantage of the omission of the storage space for these matrixes and the tedious inputs of tables in the implementations of DES, our experimental results shows that the explicit formulas are useful in some situations, such as wireless sensor networks where the memory capacity is limited, especially when the size of file for encrypting is not too large, preferably smaller than 256KB.
文摘A hybrid switching node structure with light and microwave links is proposed, which is applicable to the future data relay satellite systems, aiming at the development trend of coexistence of light- link and microwave-link in the future. An experimental system for the light and microwave hybrid switching node based on wavelength selective optical switches (WSS) and optical transceiver modules, is established. It is shown by our experiment that this hybrid switching node can realize the dynamic bandwidth allocation and wavelength routing while the bit error rate of light link is less than 10?12, which provides a method for solving the hybrid switching problem of light-link and microwave-link on the future data relay satellite systems.
文摘Telecom sectors generally operate at negative voltages to reduce the effect of corrosion caused in the metallic wire due to electrochemical reaction while communicating signals. To feed those lines and to have an effective digital data transmission, a power electronic converter referred as Modified Negative Luo Converter (MNLC) is proposed in this paper. MNLC is a high gain converter in which the output voltage increases in geometric progression. This paper portrays a novel concept of a 50 Hz pulse data transmission through RLCG (Resistance-inductance-capacitance with a shunt conductance) transmission line using MNLC. Signal frequency of 50 Hz to be transmitted is anded with a high frequency pulse that charges and discharges MNLC and produces the boosted negative output voltage. The boosted output is again transmitted through the RLCG transmission line from which 50 Hz data pulse is retrieved at the output of the transmission line by comparing with a comparator signal. This sort of MNLC aided data transmission not only introduces less loss in its transmitted data but also overcomes various health hazards of conventional radio frequency (RF) communication. This technique also proves that any data bit stream can be transmitted and retrieved using the proposed high gain DC-DC converter. The simulation model of the proposed system is implemented in MATLAB for various switching frequencies with its prototype of the converter developed and the results are verified.
文摘Power generation becomes the need of developed, developing and under developed countries to meet their increasing power requirements. When affordability increases their requirement of power increases, this happens when increased per capita consumption. The existing power scenario states that highest power is produced using firing of coals called thermal energy. A high efficiency Switched Reluctance Generator (SRG) based high frequency switching scheme to enhance the output for grid connectivity is designed, fabricated and evaluated. This proposed method generates the output for the low wind speed. It provides output at low speed because of multi-level DC-DC converter and storage system. It is an efficient solution for low wind power generation. The real time readings and results are discussed.
