High-temperature electromagnetic(EM) protection materials integrated of multiple EM protection mechanisms and functions are regarded as desirable candidates for solving EM interference over a wide temperature range.In...High-temperature electromagnetic(EM) protection materials integrated of multiple EM protection mechanisms and functions are regarded as desirable candidates for solving EM interference over a wide temperature range.In this work,a novel microwave modulator is fabricated by introducing carbonyl iron particles(CIP)/resin into channels of carbonized wood(C-wood).Innovatively,the spaced arrangement of two microwave absorbents not only achieves a synergistic enhancement of magnetic and dielectric losses,but also breaks the translational invariance of EM characteristics in the horizontal direction to obtain multiple phase discontinuities in the frequency range of 8.2-18.0 GHz achieving modulation of reflected wave radiation direction.Accordingly,CIP/C-wood microwave modulator demonstrates the maximum effective bandwidth of 5.2 GHz and the maximum EM protection efficiency over 97% with a thickness of only 1.5 mm in the temperature range 298-673 K.Besides,CIP/C-wood microwave modulator shows stable and low thermal conductivities,as well as monotonic electrical conductivity-temperature characteristics,therefore it can also achieve thermal infrared stealth and working temperature monitoring in wide temperature ranges.This work provides an inspiration for the design of high-temperature EM protection materials with multiple EM protection mechanisms and functions.展开更多
Electronic systems are vulnerable in electromagnetic interference environment. Although many solutions are adopted to solve this problem, for example shielding, filtering and grounding, noise is still introduced into ...Electronic systems are vulnerable in electromagnetic interference environment. Although many solutions are adopted to solve this problem, for example shielding, filtering and grounding, noise is still introduced into the circuit inevitably. What impresses us is the biological nervous system with a vital property of robustness in noisy environment. Some mechanisms, such as neuron population coding, degeneracy and parallel distributed processing, are believed to partly explain how the nervous system counters the noise and component failure. This paper proposes a novel concept of bio-inspired electromagnetic protec- tion making reference to the characteristic of neural information processing. A bionic model is presented here to mimic neuron populations to transform the input signal into neural pulse signal. In the proposed model, neuron provides a dynamic feedback to the adjacent one according to the concept of synaptic plasticity. A simple neural circuitry is designed to verify the rationality of the bio-inspired model for electromagnetic protection. The experiment results display that bio-inspired electromagnetic pro- tection model has more power to counter the interference and component failure.展开更多
In the ongoing evolutionary process, biological systems have displayed a fundamental and remarkable property of robustness, i.e., the property allows the system to maintain its functions despite external and internal ...In the ongoing evolutionary process, biological systems have displayed a fundamental and remarkable property of robustness, i.e., the property allows the system to maintain its functions despite external and internal perturbations. Redundancy and degeneracy are thought to be the underlying structural mechanisms of biological robustness. Inspired by this, we explored the proximate cause of the immunity of the synthetic evolved digital circuits to ESD interference and discussed the biological characteristics behind the evolutionary circuits. First, we proposed an evolutionary method for intrinsic immune circuit design. The circuits' immunity was evaluated using the functional fault models based on probability distributions. Then, several benchmark circuits, including ADDER, MAJORITY, and C17, were evolved for high intrinsic immunity. Finally, using the quantitative definitions based on information theory, we measured the topological characteristics of redundancy and degeneracy in the evolved circuits and compared their contributions to the immunity. The results show that redundant elements are neces- sary for the ESD immune circuit design, whereas degeneracy is the key to making use of the redundancy robustly and efficiently.展开更多
基金Supported by Program for the National Natural Science Foundation of China(No.52071053,U1704253)the Fundamental Research Funds for the Central Universities(DUT20GF111)the China Postdoctoral Science Foundation(2020M670748,2020M680946).
文摘High-temperature electromagnetic(EM) protection materials integrated of multiple EM protection mechanisms and functions are regarded as desirable candidates for solving EM interference over a wide temperature range.In this work,a novel microwave modulator is fabricated by introducing carbonyl iron particles(CIP)/resin into channels of carbonized wood(C-wood).Innovatively,the spaced arrangement of two microwave absorbents not only achieves a synergistic enhancement of magnetic and dielectric losses,but also breaks the translational invariance of EM characteristics in the horizontal direction to obtain multiple phase discontinuities in the frequency range of 8.2-18.0 GHz achieving modulation of reflected wave radiation direction.Accordingly,CIP/C-wood microwave modulator demonstrates the maximum effective bandwidth of 5.2 GHz and the maximum EM protection efficiency over 97% with a thickness of only 1.5 mm in the temperature range 298-673 K.Besides,CIP/C-wood microwave modulator shows stable and low thermal conductivities,as well as monotonic electrical conductivity-temperature characteristics,therefore it can also achieve thermal infrared stealth and working temperature monitoring in wide temperature ranges.This work provides an inspiration for the design of high-temperature EM protection materials with multiple EM protection mechanisms and functions.
基金This research was supported by the National Natural Science Foundation of China
文摘Electronic systems are vulnerable in electromagnetic interference environment. Although many solutions are adopted to solve this problem, for example shielding, filtering and grounding, noise is still introduced into the circuit inevitably. What impresses us is the biological nervous system with a vital property of robustness in noisy environment. Some mechanisms, such as neuron population coding, degeneracy and parallel distributed processing, are believed to partly explain how the nervous system counters the noise and component failure. This paper proposes a novel concept of bio-inspired electromagnetic protec- tion making reference to the characteristic of neural information processing. A bionic model is presented here to mimic neuron populations to transform the input signal into neural pulse signal. In the proposed model, neuron provides a dynamic feedback to the adjacent one according to the concept of synaptic plasticity. A simple neural circuitry is designed to verify the rationality of the bio-inspired model for electromagnetic protection. The experiment results display that bio-inspired electromagnetic pro- tection model has more power to counter the interference and component failure.
基金This work was supported by the National Natural Science Foundation of China under Grant 61172035.
文摘In the ongoing evolutionary process, biological systems have displayed a fundamental and remarkable property of robustness, i.e., the property allows the system to maintain its functions despite external and internal perturbations. Redundancy and degeneracy are thought to be the underlying structural mechanisms of biological robustness. Inspired by this, we explored the proximate cause of the immunity of the synthetic evolved digital circuits to ESD interference and discussed the biological characteristics behind the evolutionary circuits. First, we proposed an evolutionary method for intrinsic immune circuit design. The circuits' immunity was evaluated using the functional fault models based on probability distributions. Then, several benchmark circuits, including ADDER, MAJORITY, and C17, were evolved for high intrinsic immunity. Finally, using the quantitative definitions based on information theory, we measured the topological characteristics of redundancy and degeneracy in the evolved circuits and compared their contributions to the immunity. The results show that redundant elements are neces- sary for the ESD immune circuit design, whereas degeneracy is the key to making use of the redundancy robustly and efficiently.