L3414 mechanized mining working face (No.14 coal seam) of Lingxin Mine is under the Xitian River.The mining disturbed zone where rock properties and conditions have been changed due to mining, the safety and environme...L3414 mechanized mining working face (No.14 coal seam) of Lingxin Mine is under the Xitian River.The mining disturbed zone where rock properties and conditions have been changed due to mining, the safety and environmental protection were con- cemed greatly. Based on engineering geological environment of L3414 working face and mining factors, the color bore-bole TV inspecting, leakage of drilling fluid monitoring, simulation experiment, numerical computing, in-situ ground stress measurement and subsidence measurement, etal, these programs contribute to the formation of a scientific basis for control water safe mining and normal mining or environmental protection in the condition of existing fully-mechanized mining.展开更多
Security issues in networked control systems（NCSs） have received increasing attention in recent years.However, security protection often requires extra energy consumption, computational overhead, and time delays,whi...Security issues in networked control systems（NCSs） have received increasing attention in recent years.However, security protection often requires extra energy consumption, computational overhead, and time delays,which could adversely affect the real-time and energy-limited system. In this paper, random cryptographic protection is implemented. It is less expensive with respect to computational overhead, time, and energy consumption,compared with persistent cryptographic protection. Under the consideration of weak attackers who have little system knowledge, ungenerous attacking capability and the desire for stealthiness and random zero-measurement attacks are introduced as the malicious modification of measurements into zero signals. NCS is modeled as a stochastic system with two correlated Bernoulli distributed stochastic variables for implementation of random cryptographic protection and occurrence of random zero-measurement attacks; the stochastic stability can be analyzed using a linear matrix inequality（LMI） approach. The proposed stochastic stability analysis can help determine the proper probability of running random cryptographic protection against random zero-measurement attacks with a certain probability. Finally, a simulation example is presented based on a vertical take-off and landing（VTOL） system. The results show the effectiveness, robustness, and application of the proposed method, and are helpful in choosing the proper protection mechanism taking into account the time delay and in determining the system sampling period to increase the resistance against such attacks.展开更多
基金Supported by National Science Foundation(10402033) Ministry of Education Key Lab.of West Mining and Hazard Control Key Research Founda-tion(04JS19) and Shaanxi Province Natural Science (2003E213)
文摘L3414 mechanized mining working face (No.14 coal seam) of Lingxin Mine is under the Xitian River.The mining disturbed zone where rock properties and conditions have been changed due to mining, the safety and environmental protection were con- cemed greatly. Based on engineering geological environment of L3414 working face and mining factors, the color bore-bole TV inspecting, leakage of drilling fluid monitoring, simulation experiment, numerical computing, in-situ ground stress measurement and subsidence measurement, etal, these programs contribute to the formation of a scientific basis for control water safe mining and normal mining or environmental protection in the condition of existing fully-mechanized mining.
基金supported by the National Natural Science Foundation of China(No.61433006)the Key Research Project of Zhejiang Province,China(No.2017C01062)+3 种基金the Open Research Project of the State Key Laboratory of Industrial Control Technology,Zhejiang University,China(No.ICT1800422)the Opening Project of Shanghai Key Laboratory of Integrated Administration Technologies for Information Security,China(No.AGK2018003)the Department of Education of Zhejiang Province,China(No.Y201840611)the Zhejiang Provincial Natural Science Foundation of China(No.LY16F020019)
文摘Security issues in networked control systems（NCSs） have received increasing attention in recent years.However, security protection often requires extra energy consumption, computational overhead, and time delays,which could adversely affect the real-time and energy-limited system. In this paper, random cryptographic protection is implemented. It is less expensive with respect to computational overhead, time, and energy consumption,compared with persistent cryptographic protection. Under the consideration of weak attackers who have little system knowledge, ungenerous attacking capability and the desire for stealthiness and random zero-measurement attacks are introduced as the malicious modification of measurements into zero signals. NCS is modeled as a stochastic system with two correlated Bernoulli distributed stochastic variables for implementation of random cryptographic protection and occurrence of random zero-measurement attacks; the stochastic stability can be analyzed using a linear matrix inequality（LMI） approach. The proposed stochastic stability analysis can help determine the proper probability of running random cryptographic protection against random zero-measurement attacks with a certain probability. Finally, a simulation example is presented based on a vertical take-off and landing（VTOL） system. The results show the effectiveness, robustness, and application of the proposed method, and are helpful in choosing the proper protection mechanism taking into account the time delay and in determining the system sampling period to increase the resistance against such attacks.
