To study the damage mechanism of single-layer reticulated domes subject to severe earthquakes, three limit states of single-layer reticulated domes under earthquakes are defined firstly in this paper. Then, two failur...To study the damage mechanism of single-layer reticulated domes subject to severe earthquakes, three limit states of single-layer reticulated domes under earthquakes are defined firstly in this paper. Then, two failure modes are presented by analyzing damage behaviors, and their characteristics are pointed out respectively. Furthermore, the damage process is analyzed and the causes of structural damage in different levels are studied. Finally, by comparing deformation and vibration status of domes with different failure modes, the principles of different failures are revealed and an integrated frame of damage mechanism is set up.展开更多
Cosmic radiation has several effects on the On-Board Processing(OBP)platform in satellite communications systems,and Single Event Upsets(SEUs)are one of its most important effects.In order to protect the Finite Impuls...Cosmic radiation has several effects on the On-Board Processing(OBP)platform in satellite communications systems,and Single Event Upsets(SEUs)are one of its most important effects.In order to protect the Finite Impulse Response(FIR)filters against SEU,this paper proposes a novel Residue Number(RN)-based method.The proposed method applies the transpose form of the FIR filter to avoid the fault missing caused by SEU on shift registers.It also adjusts the input intelligently to avoid the fault missing caused by SEU on the filter coefficients.After all the fault missing events are avoided,the modulus can be minimised to achieve the minimum overhead.Theoretical analysis and simulation results show that the noise introduced by the input adjustment is negligible.Fault injection shows that the fault missing rate of the proposed method is zero.Finally,FPGA implementation shows that the overhead of the proposed method is approximately 75% of Triple Modular Redundancy,and is only 1%-2% higher than that of the traditional RN-based design.展开更多
In the literature, many works on determining inspection interval by the delay time concept generally assumed that the time of inspection span and the time of failure renewal are negligible. However, in realistic cases...In the literature, many works on determining inspection interval by the delay time concept generally assumed that the time of inspection span and the time of failure renewal are negligible. However, in realistic cases, the above time should not be neglected for both the time itself and its effect. In order to model the effect of the possible overlapping of inspection span with failure downtime on determining the optimal inspection interval, we propose a block-based inspection model for a single component-based on delay time concept. We further compare this model with the age-based model to show the practical sense. The developed models are also demonstrated by numerical examples.展开更多
基金Sponsored by the National Natural Science Foundation of China(Grant No.90715034)
文摘To study the damage mechanism of single-layer reticulated domes subject to severe earthquakes, three limit states of single-layer reticulated domes under earthquakes are defined firstly in this paper. Then, two failure modes are presented by analyzing damage behaviors, and their characteristics are pointed out respectively. Furthermore, the damage process is analyzed and the causes of structural damage in different levels are studied. Finally, by comparing deformation and vibration status of domes with different failure modes, the principles of different failures are revealed and an integrated frame of damage mechanism is set up.
基金supported by the National High Technical Research and Development Program of China (863 Program) "Research on the Key Technology for the Base Band Signal Processing for Onboard Payload"the Sino-Japan Joint Fund "Key Technique Research for GSS Integrated Mobile Satellite Communications"+2 种基金Tsinghua University Initiative Scientific Research Program "Key Technologies of SkyEarth Integration Wireless Communication Network" under Grant No. 2010 THZ03the National Key Basic Research Program of China(973 Program) under Grant No. 2012CB316000the Spanish Ministry of Science and Education under Grant No. AYA2009-13300-C03
文摘Cosmic radiation has several effects on the On-Board Processing(OBP)platform in satellite communications systems,and Single Event Upsets(SEUs)are one of its most important effects.In order to protect the Finite Impulse Response(FIR)filters against SEU,this paper proposes a novel Residue Number(RN)-based method.The proposed method applies the transpose form of the FIR filter to avoid the fault missing caused by SEU on shift registers.It also adjusts the input intelligently to avoid the fault missing caused by SEU on the filter coefficients.After all the fault missing events are avoided,the modulus can be minimised to achieve the minimum overhead.Theoretical analysis and simulation results show that the noise introduced by the input adjustment is negligible.Fault injection shows that the fault missing rate of the proposed method is zero.Finally,FPGA implementation shows that the overhead of the proposed method is approximately 75% of Triple Modular Redundancy,and is only 1%-2% higher than that of the traditional RN-based design.
文摘In the literature, many works on determining inspection interval by the delay time concept generally assumed that the time of inspection span and the time of failure renewal are negligible. However, in realistic cases, the above time should not be neglected for both the time itself and its effect. In order to model the effect of the possible overlapping of inspection span with failure downtime on determining the optimal inspection interval, we propose a block-based inspection model for a single component-based on delay time concept. We further compare this model with the age-based model to show the practical sense. The developed models are also demonstrated by numerical examples.
