Alzheimer＇s disease （AD） is the most frequent cause of dementia in the western world. In clinical terms, AD is characterized by progres- sive cognitive decline that usually begins with memory impairment. As the dis...Alzheimer＇s disease （AD） is the most frequent cause of dementia in the western world. In clinical terms, AD is characterized by progres- sive cognitive decline that usually begins with memory impairment. As the disease progresses, AD inevitably affects all intellectual functions including executive functions, leading to complete dependence for basic activities of daily life and premature death.展开更多
High-fidelity aerodynamic optimization of compressors is afflicted by the"curse of dimensionality",which limits its engineering applications.This paper proposes a new multi-degrees-of-freedom(MDOF)surface pa...High-fidelity aerodynamic optimization of compressors is afflicted by the"curse of dimensionality",which limits its engineering applications.This paper proposes a new multi-degrees-of-freedom(MDOF)surface parameterization method that combines the characteristics of conventional surface parameterization methods,low-dimensionality and surface smoothness,with the advantages of design flexibility and ease of construction.The proposed method is applied to the high-fidelity aerodynamic optimization of Rotor37.An optimized solution is obtained within 111 h by combining a phased optimization strategy based on the idea of modal optimization.To explore a better way of setting the control variables of the blade body,two methods of varying the control points of the suction and pressure surfaces,independent change and synchronous change,are compared.Synchronous change has better flexibility,and under the condition of satisfying the constraints,it increases the efficiency at the design point by 2.2%and the surge margin by 0.5%.This demonstrates the effectiveness of the proposed method in the high-fidelity aerodynamic optimization of compressors.It also provides technical support to solve the"curse of dimensionality"problem.展开更多
Intermediate spoofing can impact most off-the-shelf Global Navigation Satellite Systems （GNSS） receivers, therefore low cost detection of such spoofing is very important to protect the reliability of the GNSS receiv...Intermediate spoofing can impact most off-the-shelf Global Navigation Satellite Systems （GNSS） receivers, therefore low cost detection of such spoofing is very important to protect the reliability of the GNSS receivers used in critical safety and financial applications. This paper presents two strategies to analyze attacks by intermediate spoofing attackers to identify the weaknesses of such attacks. The analyses lead to a code and carrier phase consistency detection method with simulation results showing that this method can indicate the receiver when spoofing has occurred. The method can be used by most receivers, is inexpensive, and requires only a small software upgrade.展开更多
文摘Alzheimer＇s disease （AD） is the most frequent cause of dementia in the western world. In clinical terms, AD is characterized by progres- sive cognitive decline that usually begins with memory impairment. As the disease progresses, AD inevitably affects all intellectual functions including executive functions, leading to complete dependence for basic activities of daily life and premature death.
基金financially supported by Civil Aircraft Special Project(Grant No.MJZ-2017-D-32(Y81H061A41)).
文摘High-fidelity aerodynamic optimization of compressors is afflicted by the"curse of dimensionality",which limits its engineering applications.This paper proposes a new multi-degrees-of-freedom(MDOF)surface parameterization method that combines the characteristics of conventional surface parameterization methods,low-dimensionality and surface smoothness,with the advantages of design flexibility and ease of construction.The proposed method is applied to the high-fidelity aerodynamic optimization of Rotor37.An optimized solution is obtained within 111 h by combining a phased optimization strategy based on the idea of modal optimization.To explore a better way of setting the control variables of the blade body,two methods of varying the control points of the suction and pressure surfaces,independent change and synchronous change,are compared.Synchronous change has better flexibility,and under the condition of satisfying the constraints,it increases the efficiency at the design point by 2.2%and the surge margin by 0.5%.This demonstrates the effectiveness of the proposed method in the high-fidelity aerodynamic optimization of compressors.It also provides technical support to solve the"curse of dimensionality"problem.
基金National Natural Science Foundation of China(No.61101070)
文摘Intermediate spoofing can impact most off-the-shelf Global Navigation Satellite Systems （GNSS） receivers, therefore low cost detection of such spoofing is very important to protect the reliability of the GNSS receivers used in critical safety and financial applications. This paper presents two strategies to analyze attacks by intermediate spoofing attackers to identify the weaknesses of such attacks. The analyses lead to a code and carrier phase consistency detection method with simulation results showing that this method can indicate the receiver when spoofing has occurred. The method can be used by most receivers, is inexpensive, and requires only a small software upgrade.
