Semitransparent organic solar cells(ST-OSCs)are promising for building-integrated photovoltaics,offering power generation,transparency and heat insulation.High performance ST-OSCs need sophisticated optical management...Semitransparent organic solar cells(ST-OSCs)are promising for building-integrated photovoltaics,offering power generation,transparency and heat insulation.High performance ST-OSCs need sophisticated optical management to balance the competing demands of power conversion efficiency(PCE)and average visible transmittance(AVT)for various applications.Here,a type of aperiodic band-pass filter(ABPF)made from LiF and ZnS are developed to selectively alter visible light transmission and near-infrared(NIR)reflection.This ABPF allows the active layers of ST-OSCs to re-harvest unabsorbed NIR photons,compensating for the loss of photocurrent caused by the high AVT of ST-OSCs.By carefully adjusting the thicknesses of individual layers within ABPFs,we can modulate their photonic bandgaps,enabling ST-OSCs to achieve multifunctional performance.ST-OSCs combined with the ABPF-1 demonstrate a remarkable light utilization efficiency(LUE)of 5.40%,a PCE of 14.21%and an AVT of 38.0%,which represent some of the highest values reported for ST-OSCs.Moreover,the ST-OSCs are equipped with excellent color neutrality and heat insulation functions.The ST-OSCs employing ABPF-2 exhibit a LUE of 4.78%,a color rendering index of 87.5 and an infrared rejection rate of 91.6%.This work offers an effective method for employing ABPFs in the creation of high-performance multifunctional ST-OSCs.展开更多
By the use of cross-correlation measures, the response of a symmetric Schmitt trigger (ST) driven by a random binary signal and white Gaussian noise is investigated. The results show that the information transmission...By the use of cross-correlation measures, the response of a symmetric Schmitt trigger (ST) driven by a random binary signal and white Gaussian noise is investigated. The results show that the information transmission can be enhanced when a certain amount of noise is presented, i.e., aperiodic stochastic resonance (ASR). Then, the influence of signal amplitude and the ST threshold on ASR is examined, the applicability of the ST in reducing the noise level of random signal transmission and improving the quality of output signal via ASR effect is illustrated. This research is of great interest in the field of digital communications.展开更多
Because of descriptive nonlinearity and computational inefficiency,topology optimization with fatigue life under aperiodic loads has developed slowly.A fatigue constraint topology optimization method based on bidirect...Because of descriptive nonlinearity and computational inefficiency,topology optimization with fatigue life under aperiodic loads has developed slowly.A fatigue constraint topology optimization method based on bidirectional evolutionary structural optimization(BESO)under an aperiodic load is proposed in this paper.In viewof the severe nonlinearity of fatigue damagewith respect to design variables,effective stress cycles are extracted through transient dynamic analysis.Based on the Miner cumulative damage theory and life requirements,a fatigue constraint is first quantified and then transformed into a stress problem.Then,a normalized termination criterion is proposed by approximatemaximum stress measured by global stress using a P-normaggregation function.Finally,optimization examples show that the proposed algorithm can not only meet the requirements of fatigue life but also obtain a reasonable configuration.展开更多
Energy consumption has become a key metric for evaluating how good an embedded system is,alongside more performance metrics like respecting operation deadlines and speed of execution.Schedulability improvement is no l...Energy consumption has become a key metric for evaluating how good an embedded system is,alongside more performance metrics like respecting operation deadlines and speed of execution.Schedulability improvement is no longer the only metric by which optimality is judged.In fact,energy efficiency is becoming a preferred choice with a fundamental objective to optimize the system's lifetime.In this work,we propose an optimal energy efficient scheduling algorithm for aperiodic real-time jobs to reduce CPU energy consumption.Specifically,we apply the concept of real-time process scheduling to a dynamic voltage and frequency scaling(DVFS)technique.We address a variant of earliest deadline first(EDF)scheduling algorithm called energy saving-dynamic voltage and frequency scaling(ES-DVFS)algorithm that is suited to unpredictable future energy production and irregular job arrivals.We prove that ES-DVFS cannot attain a total value greater than C/ˆSα,whereˆS is the minimum speed of any job and C is the available energy capacity.We also investigate the implications of having in advance,information about the largest job size and the minimum speed used for the competitive factor of ES-DVFS.We show that such advance knowledge makes possible the design of semi-on-line algorithm,ES-DVFS∗∗,that achieved a constant competitive factor of 0.5 which is proved as an optimal competitive factor.The experimental study demonstrates that substantial energy savings and highest percentage of feasible job sets can be obtained through our solution that combines EDF and DVFS optimally under the given aperiodic jobs and energy models.展开更多
This paper examines the stabilization problem of a distributed networked control system under the effect of cyberattacks by employing a hybrid aperiodic triggering mechanism.The cyber-attack considered in the paper is...This paper examines the stabilization problem of a distributed networked control system under the effect of cyberattacks by employing a hybrid aperiodic triggering mechanism.The cyber-attack considered in the paper is a stochastic deception attack at the sensor-controller end. The probability of the occurrence of attack on a subsystem is represented using a random variable. A decentralized hybrid sampled-data strategy is introduced to save energy consumption and reduce the transmission load of the network. In the proposed decentralized strategy, each subsystem can decide independently whether its state should be transmitted to the controller or not. The scheme of the hybrid triggering mechanism for each subsystem composed of two stages: In the first stage, the next sampling instant is computed using a self-triggering strategy. Subsequently, in the second stage, an event-triggering condition is checked at these sampling instants and the control signal is computed only if the event-triggering condition is violated. The self-triggering condition used in the first stage is dependent on the selection of eventtriggering condition of the second stage. Finally, a comparison of the proposed approach with other triggering mechanisms existing in the literature is presented in terms of the sampling instants,transmission frequency and performance measures through simulation examples.展开更多
The popularly used circulant matrix model of deconvolution is mostly heavily ill-posed or singular and it is not suitable to many blind deconvolution problems. The aperiodic matrix model can improve the condition numb...The popularly used circulant matrix model of deconvolution is mostly heavily ill-posed or singular and it is not suitable to many blind deconvolution problems. The aperiodic matrix model can improve the condition number of deconvolution problems and its accommodation is much wider than the circulant one's. This paper discusses a comparison of the two models including their ill-posedness, the rationality of the approximation by the models, and their computational efficiency. The comparison shows that the aperiodic model is promising in the development of new restoration algorithms.展开更多
Stochastic resonance （SR） is based on the cooperative effect between the stochastic dynamical system and the external forcing. As is well known, the cooperative effect is produced by adding noises. In this paper, we...Stochastic resonance （SR） is based on the cooperative effect between the stochastic dynamical system and the external forcing. As is well known, the cooperative effect is produced by adding noises. In this paper, we show the evidence that by changing the system parameters and the signal intensity, a nonlinear system in the presence of an input aperiodic signal can yield the cooperative effect, with the noise fixed. To quantify the nonlinear system output, we determine the theoretical bit error rate （BER）. By numerical simulation, the validity of the theoretical derivation is checked. Besides, we show that parameter-induced SR is more realizable than SR via adding noises, especially when the noise intensity exceeds the resonance level, or when the characteristic of the noise is not known.展开更多
The idea of network splitting according to time delay and weight is introduced.Based on the cyber physical systems(CPS),a class of multi-weighted complex transportation networks with multiple delays is modeled.The fin...The idea of network splitting according to time delay and weight is introduced.Based on the cyber physical systems(CPS),a class of multi-weighted complex transportation networks with multiple delays is modeled.The finite-time synchronization of the proposed complex transportation networks model is studied systematically.On the basis of the theory of stability,the technique of adaptive control,aperiodically intermittent control and finite-time control,the aperiodically intermittent adaptive finite-time synchronization controller is designed.The controller designed in this paper is beneficial for understanding the synchronization in multi-weighted complex transportation networks with multiple delays.In addition,the conditions for the existence of finite time synchronization have been discussed in detail.And the specific value of the settling finite time for synchronization is obtained.Moreover,the outer coupling configuration matrices are not required to be irreducible or symmetric.Finally,simulation results of the finite-time synchronization problem are given to illustrate the correctness of the results obtained.展开更多
Multilayer interference mirrors play a pivotal role in spectroscopic diagnostic systems,which probe electron temperature and density during inertial confinement fusion processes.In this study,aperiodic Mo/B_(4)C multi...Multilayer interference mirrors play a pivotal role in spectroscopic diagnostic systems,which probe electron temperature and density during inertial confinement fusion processes.In this study,aperiodic Mo/B_(4)C multilayer mirrors of varied thick-nesses were investigated for X-ray plasma diagnostics at the 9.67-keV W-Lβline.The thickness distribution of the aperiodic multilayers was designed using the first Bragg diffraction condition and then optimized through a simplex algorithm to realize a narrow bandwidth and consistent spectral response.To enhance spectral accuracy,further refinements were undertaken by matching the grazing incidence X-ray reflectivity data with actual structural parameters.X-ray reflectivity measurements from the SSRF synchrotron radiation facility on the optimized sample showed a reflectivity of 29.7±2.6%,flat-band range of 1.3 keV,and bandwidth of 1.7 keV,making it suitable for high-temperature plasma diagnostics.The study explored the potential of predicting the 9.67 keV reflectivity spectrum using the fitting data from the grazing incidence X-ray reflectivity curves at 8.05 keV.Additionally,the short-term thermal stability of an aperiodic multilayer was assessed using temperature-dependent in situ X-ray measurements.Shifts in the reflectivity spectrum during annealing were attributed to interdiffusion and interfacial relaxation.The research team recommends the aperiodic Mo/B_(4)C multilayer mirror for operations below 300℃.展开更多
We study the entanglement between the internal(coin)and the external(position)degrees of freedom in the dynamic and the static deterministic aperiodic quantum walks(QWs).For the dynamic(static)aperiodic QWs,the coin d...We study the entanglement between the internal(coin)and the external(position)degrees of freedom in the dynamic and the static deterministic aperiodic quantum walks(QWs).For the dynamic(static)aperiodic QWs,the coin depends on the time(position)and takes two coins C(α)and C(β)arranged in the two classes of generalized Fibonacci(GF)and the Thue–Morse(TM)sequences.We found that for the dynamic QWs,the entanglement of three kinds of the aperiodic QWs are close to the maximal value,which are all much larger than that of the homogeneous QWs.Further,the first class of GF(1st GF)QWs can achieve the maximum entangled state,which is similar to that of the dynamic disordered QWs.And the entanglement of 1st GF QWs is greater than that of the TM QWs,being followed closely by the entanglement of the second class of GF(2nd GF)QWs.For the static QWs,the entanglement of three kinds of the aperiodic QWs are also close to the maximal value and 1st GF QWs can achieve the maximum entangled state.The entanglement of the TM QWs is between1st GF QWs and 2nd GF QWs.However,the entanglement of the static disordered QWs is less than that of three kinds of the aperiodic QWs.This is different from those of the dynamic QWs.From these results,we can conclude that the dynamic and static 1st GF QWs can also be considered as maximal entanglement generators.展开更多
The structure aperiodicities can influence seriously the features of motion of soliton excited in the α-helix protein molecules with three channels. We study the influence of structure aperiodicities on the features ...The structure aperiodicities can influence seriously the features of motion of soliton excited in the α-helix protein molecules with three channels. We study the influence of structure aperiodicities on the features of the soliton in the improved model by numerical simulation and Runge-Kulta method. The results obtained show that the new soliton is very robust against the structure aperiodieities including large disorder in the sequence of mass of the amino acids and fluctuations of spring constant, coupling constant, dipole-dipole interactional constant, ground state energy and chain-chain interaction. However, very strong structure aperiodieities can also destroy the stability of the soliton in the α-helix protein molecules.展开更多
In this paper, a novel scheduling mechanism is proposed to handle the real-time overload problem by maximizing the cumulative values of three types of tasks： the soft, the hard and the imprecise tasks. The simulation...In this paper, a novel scheduling mechanism is proposed to handle the real-time overload problem by maximizing the cumulative values of three types of tasks： the soft, the hard and the imprecise tasks. The simulation results show that the performance of our presented mechanism in this paper is greatly improved, much better than that of the other three mechanisms： earliest deadline first （EDF）, highest value first （HVF） and highest density first （HDF）, under the same conditions of all nominal loads and task type proportions.展开更多
The minimum aperiodic crosscorrelation of binary sequences of size M and length n over the alphabet E={1, -1} has been obtained by Levenshtein for M≥4 and n≥2 These bounds improve a long standing bound giv...The minimum aperiodic crosscorrelation of binary sequences of size M and length n over the alphabet E={1, -1} has been obtained by Levenshtein for M≥4 and n≥2 These bounds improve a long standing bound given by Welch. In this paper, the Sarwate bounds for codes over the p th roots of unity with the same parameters M and n are discussed, that is,the lower bounds and trade off are established for the maximum magnitude of the aperiodic crosscorrelation function and the maximum magnitude of the out of phase aperiodic autocorrelation function for the sets of periodic sequences with the same parameters M and n by using the modified Levenshtein method. The results show that new bounds are tighter than Sarwate bounds and Levenshtein bounds.展开更多
In this article we summarize some aperiodic checkpoint placement algorithms for a software system over infinite and finite operation time horizons, and compare them in terms of computational accuracy. The underlying p...In this article we summarize some aperiodic checkpoint placement algorithms for a software system over infinite and finite operation time horizons, and compare them in terms of computational accuracy. The underlying problem is formulated as the maximization of steady-state system availability and is to determine the optimal aperiodic checkpoint sequence. We present two exact computation algorithms in both forward and backward manners and two approximate ones;constant hazard approximation and fluid approximation, toward this end. In numerical examples with Weibull system failure time distribution, it is shown that the combined algorithm with the fluid approximation can calculate effectively the exact solutions on the optimal aperiodic checkpoint sequence.展开更多
The localization characteristics of the in-plane elastic waves in locally resonant aperiodic phononic crystals are examined in this study. In particular, the phononic crystals generated according to the Thue-Morse, Ru...The localization characteristics of the in-plane elastic waves in locally resonant aperiodic phononic crystals are examined in this study. In particular, the phononic crystals generated according to the Thue-Morse, Rudin-Shapiro and Period-Doubling sequences are theoretically investigated by using the extended transfer matrix method. For comparison, the binary and ternary locally resonant systems are considered, and their band structures are characterized by using the localization factors. Moreover, the influences of structural arrangement, material combination, incidence angle, number of components, length ratio, and random disorder on the band structures are also discussed. Some novel and interesting phenomena are observed and discussed.展开更多
This paper addresses the new algebraic test to check the aperiodic stability of two dimensional linear time invariant discrete systems. Initially, the two dimensional characteristics equations are converted into equiv...This paper addresses the new algebraic test to check the aperiodic stability of two dimensional linear time invariant discrete systems. Initially, the two dimensional characteristics equations are converted into equivalent one-dimensional equation. Further Fuller’s idea is applied on the equivalent one-dimensional characteristics equation. Then using the co-efficient of the characteristics equation, the routh table is formed to ascertain the aperiodic stability of the given two-dimensional linear discrete system. The illustrations were presented to show the applicability of the proposed technique.展开更多
In the previous work of garbage collection （GC） models, scheduling analysis was given based on an assumption that there were no aperiodic mutator tasks. However, it is not true in practical real-time systems. The GC...In the previous work of garbage collection （GC） models, scheduling analysis was given based on an assumption that there were no aperiodic mutator tasks. However, it is not true in practical real-time systems. The GC algorithm which can schedule aperiodic tasks is proposed, and the variance of live memory is analyzed. In this algorithm, active tasks are deferred to be processed by GC until the states of tasks become inactive, and the saved sporadic server time can be used to schedule aperiodic tasks. Scheduling the sample task sets demonstrates that this algorithm in this paper can schedule aperiodic tasks and decrease GC work. Thus, the GC algorithm proposed is more flexible and portable.展开更多
The stability of matter is a historical problem that tackles the linearity of the bulk energy with the total number of particles M.The classical and quantum variants have been proved using mostly Coulomb interaction b...The stability of matter is a historical problem that tackles the linearity of the bulk energy with the total number of particles M.The classical and quantum variants have been proved using mostly Coulomb interaction between electrons and nuclei,either fixed or submitted to thermal fluctuation.The classical dipole–dipole interaction is addressed here as the sole energy on regular tilings.We prove that the system on any regular(periodic)grid is always stable.The aperiodic or quasicrystal instance is conjectured and numerically illustrated for the particular cases of the Penrose P2 and the recently discovered hat monotiles.展开更多
Classical computation of electronic properties in large-scale materials remains challenging.Quantum computation has the potential to offer advantages in memory footprint and computational scaling.However,general and v...Classical computation of electronic properties in large-scale materials remains challenging.Quantum computation has the potential to offer advantages in memory footprint and computational scaling.However,general and viable quantum algorithms for simulating large-scale materials are still limited.We propose and implement random-state quantum algorithms to calculate electronic-structure properties of real materials.Using a random state circuit on a small number of qubits,we employ real-time evolution with first-order Trotter decomposition and Hadamard test to obtain electronic density of states,and we develop a modified quantum phase estimation algorithm to calculate real-space local density of states via direct quantum measurements.Furthermore,we validate these algorithms by numerically computing the density of states and spatial distributions of electronic states in graphene,twisted bilayer graphene quasicrystals,and fractal lattices,covering system sizes from hundreds to thousands of atoms.Our results manifest that the random-state quantum algorithms provide a general and qubit-efficient route to scalable simulations of electronic properties in large-scale periodic and aperiodic materials.展开更多
基金the financial support provided by the National Natural Science Foundation of China(22361132545,52273200,52473199)the Science and Technology Development Program of Jilin Province(20230101131JC)+1 种基金RSCF Grant(24-4300178)Ministry of Science and Higher Education of the Russian Federation(Contract No.075-00276-25-00)。
文摘Semitransparent organic solar cells(ST-OSCs)are promising for building-integrated photovoltaics,offering power generation,transparency and heat insulation.High performance ST-OSCs need sophisticated optical management to balance the competing demands of power conversion efficiency(PCE)and average visible transmittance(AVT)for various applications.Here,a type of aperiodic band-pass filter(ABPF)made from LiF and ZnS are developed to selectively alter visible light transmission and near-infrared(NIR)reflection.This ABPF allows the active layers of ST-OSCs to re-harvest unabsorbed NIR photons,compensating for the loss of photocurrent caused by the high AVT of ST-OSCs.By carefully adjusting the thicknesses of individual layers within ABPFs,we can modulate their photonic bandgaps,enabling ST-OSCs to achieve multifunctional performance.ST-OSCs combined with the ABPF-1 demonstrate a remarkable light utilization efficiency(LUE)of 5.40%,a PCE of 14.21%and an AVT of 38.0%,which represent some of the highest values reported for ST-OSCs.Moreover,the ST-OSCs are equipped with excellent color neutrality and heat insulation functions.The ST-OSCs employing ABPF-2 exhibit a LUE of 4.78%,a color rendering index of 87.5 and an infrared rejection rate of 91.6%.This work offers an effective method for employing ABPFs in the creation of high-performance multifunctional ST-OSCs.
文摘By the use of cross-correlation measures, the response of a symmetric Schmitt trigger (ST) driven by a random binary signal and white Gaussian noise is investigated. The results show that the information transmission can be enhanced when a certain amount of noise is presented, i.e., aperiodic stochastic resonance (ASR). Then, the influence of signal amplitude and the ST threshold on ASR is examined, the applicability of the ST in reducing the noise level of random signal transmission and improving the quality of output signal via ASR effect is illustrated. This research is of great interest in the field of digital communications.
基金Chinese National Natural Science Foundation(No.51890881)Science and Technology Project of Hebei Education Department(Nos.ZD2020156,QN2018228).
文摘Because of descriptive nonlinearity and computational inefficiency,topology optimization with fatigue life under aperiodic loads has developed slowly.A fatigue constraint topology optimization method based on bidirectional evolutionary structural optimization(BESO)under an aperiodic load is proposed in this paper.In viewof the severe nonlinearity of fatigue damagewith respect to design variables,effective stress cycles are extracted through transient dynamic analysis.Based on the Miner cumulative damage theory and life requirements,a fatigue constraint is first quantified and then transformed into a stress problem.Then,a normalized termination criterion is proposed by approximatemaximum stress measured by global stress using a P-normaggregation function.Finally,optimization examples show that the proposed algorithm can not only meet the requirements of fatigue life but also obtain a reasonable configuration.
文摘Energy consumption has become a key metric for evaluating how good an embedded system is,alongside more performance metrics like respecting operation deadlines and speed of execution.Schedulability improvement is no longer the only metric by which optimality is judged.In fact,energy efficiency is becoming a preferred choice with a fundamental objective to optimize the system's lifetime.In this work,we propose an optimal energy efficient scheduling algorithm for aperiodic real-time jobs to reduce CPU energy consumption.Specifically,we apply the concept of real-time process scheduling to a dynamic voltage and frequency scaling(DVFS)technique.We address a variant of earliest deadline first(EDF)scheduling algorithm called energy saving-dynamic voltage and frequency scaling(ES-DVFS)algorithm that is suited to unpredictable future energy production and irregular job arrivals.We prove that ES-DVFS cannot attain a total value greater than C/ˆSα,whereˆS is the minimum speed of any job and C is the available energy capacity.We also investigate the implications of having in advance,information about the largest job size and the minimum speed used for the competitive factor of ES-DVFS.We show that such advance knowledge makes possible the design of semi-on-line algorithm,ES-DVFS∗∗,that achieved a constant competitive factor of 0.5 which is proved as an optimal competitive factor.The experimental study demonstrates that substantial energy savings and highest percentage of feasible job sets can be obtained through our solution that combines EDF and DVFS optimally under the given aperiodic jobs and energy models.
文摘This paper examines the stabilization problem of a distributed networked control system under the effect of cyberattacks by employing a hybrid aperiodic triggering mechanism.The cyber-attack considered in the paper is a stochastic deception attack at the sensor-controller end. The probability of the occurrence of attack on a subsystem is represented using a random variable. A decentralized hybrid sampled-data strategy is introduced to save energy consumption and reduce the transmission load of the network. In the proposed decentralized strategy, each subsystem can decide independently whether its state should be transmitted to the controller or not. The scheme of the hybrid triggering mechanism for each subsystem composed of two stages: In the first stage, the next sampling instant is computed using a self-triggering strategy. Subsequently, in the second stage, an event-triggering condition is checked at these sampling instants and the control signal is computed only if the event-triggering condition is violated. The self-triggering condition used in the first stage is dependent on the selection of eventtriggering condition of the second stage. Finally, a comparison of the proposed approach with other triggering mechanisms existing in the literature is presented in terms of the sampling instants,transmission frequency and performance measures through simulation examples.
文摘The popularly used circulant matrix model of deconvolution is mostly heavily ill-posed or singular and it is not suitable to many blind deconvolution problems. The aperiodic matrix model can improve the condition number of deconvolution problems and its accommodation is much wider than the circulant one's. This paper discusses a comparison of the two models including their ill-posedness, the rationality of the approximation by the models, and their computational efficiency. The comparison shows that the aperiodic model is promising in the development of new restoration algorithms.
基金Project supported by the National Natural Science Foundation of China （Grant No 10332030） and the State Key Program for Basic Research of China （Grant No 5132103ZZT21B）.
文摘Stochastic resonance （SR） is based on the cooperative effect between the stochastic dynamical system and the external forcing. As is well known, the cooperative effect is produced by adding noises. In this paper, we show the evidence that by changing the system parameters and the signal intensity, a nonlinear system in the presence of an input aperiodic signal can yield the cooperative effect, with the noise fixed. To quantify the nonlinear system output, we determine the theoretical bit error rate （BER）. By numerical simulation, the validity of the theoretical derivation is checked. Besides, we show that parameter-induced SR is more realizable than SR via adding noises, especially when the noise intensity exceeds the resonance level, or when the characteristic of the noise is not known.
基金Project supported by the National Natural Science Foundation of China(Grant No.61803275)Liaoning Provincial Department of Education Scientific Research Fund Project,China(Grant Nos.lnjc202018 and lnzd202007)+1 种基金Liaoning BaiQianWan Talents Program(Grant No.2017076)Liaoning Province Doctor Starting Foundation(Grant No.20170520283).
文摘The idea of network splitting according to time delay and weight is introduced.Based on the cyber physical systems(CPS),a class of multi-weighted complex transportation networks with multiple delays is modeled.The finite-time synchronization of the proposed complex transportation networks model is studied systematically.On the basis of the theory of stability,the technique of adaptive control,aperiodically intermittent control and finite-time control,the aperiodically intermittent adaptive finite-time synchronization controller is designed.The controller designed in this paper is beneficial for understanding the synchronization in multi-weighted complex transportation networks with multiple delays.In addition,the conditions for the existence of finite time synchronization have been discussed in detail.And the specific value of the settling finite time for synchronization is obtained.Moreover,the outer coupling configuration matrices are not required to be irreducible or symmetric.Finally,simulation results of the finite-time synchronization problem are given to illustrate the correctness of the results obtained.
基金This work was supported by the National Natural Science Foundation of China(NSFC)(Nos.11875204 and U1932167)Fundamental Research Funds for the Central Universities(Nos.22120210446 and 22120180070)the Presidential Foundation of China Academy of Engineering Physics(No.YZJJLX2019011).
文摘Multilayer interference mirrors play a pivotal role in spectroscopic diagnostic systems,which probe electron temperature and density during inertial confinement fusion processes.In this study,aperiodic Mo/B_(4)C multilayer mirrors of varied thick-nesses were investigated for X-ray plasma diagnostics at the 9.67-keV W-Lβline.The thickness distribution of the aperiodic multilayers was designed using the first Bragg diffraction condition and then optimized through a simplex algorithm to realize a narrow bandwidth and consistent spectral response.To enhance spectral accuracy,further refinements were undertaken by matching the grazing incidence X-ray reflectivity data with actual structural parameters.X-ray reflectivity measurements from the SSRF synchrotron radiation facility on the optimized sample showed a reflectivity of 29.7±2.6%,flat-band range of 1.3 keV,and bandwidth of 1.7 keV,making it suitable for high-temperature plasma diagnostics.The study explored the potential of predicting the 9.67 keV reflectivity spectrum using the fitting data from the grazing incidence X-ray reflectivity curves at 8.05 keV.Additionally,the short-term thermal stability of an aperiodic multilayer was assessed using temperature-dependent in situ X-ray measurements.Shifts in the reflectivity spectrum during annealing were attributed to interdiffusion and interfacial relaxation.The research team recommends the aperiodic Mo/B_(4)C multilayer mirror for operations below 300℃.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11575087 and 11175087)
文摘We study the entanglement between the internal(coin)and the external(position)degrees of freedom in the dynamic and the static deterministic aperiodic quantum walks(QWs).For the dynamic(static)aperiodic QWs,the coin depends on the time(position)and takes two coins C(α)and C(β)arranged in the two classes of generalized Fibonacci(GF)and the Thue–Morse(TM)sequences.We found that for the dynamic QWs,the entanglement of three kinds of the aperiodic QWs are close to the maximal value,which are all much larger than that of the homogeneous QWs.Further,the first class of GF(1st GF)QWs can achieve the maximum entangled state,which is similar to that of the dynamic disordered QWs.And the entanglement of 1st GF QWs is greater than that of the TM QWs,being followed closely by the entanglement of the second class of GF(2nd GF)QWs.For the static QWs,the entanglement of three kinds of the aperiodic QWs are also close to the maximal value and 1st GF QWs can achieve the maximum entangled state.The entanglement of the TM QWs is between1st GF QWs and 2nd GF QWs.However,the entanglement of the static disordered QWs is less than that of three kinds of the aperiodic QWs.This is different from those of the dynamic QWs.From these results,we can conclude that the dynamic and static 1st GF QWs can also be considered as maximal entanglement generators.
基金supported by the National "973" Project of China under Grant No. 2007CB936103
文摘The structure aperiodicities can influence seriously the features of motion of soliton excited in the α-helix protein molecules with three channels. We study the influence of structure aperiodicities on the features of the soliton in the improved model by numerical simulation and Runge-Kulta method. The results obtained show that the new soliton is very robust against the structure aperiodieities including large disorder in the sequence of mass of the amino acids and fluctuations of spring constant, coupling constant, dipole-dipole interactional constant, ground state energy and chain-chain interaction. However, very strong structure aperiodieities can also destroy the stability of the soliton in the α-helix protein molecules.
基金supported by the Shanghai Applied Materials Foundation (Grant No.06SA18)
文摘In this paper, a novel scheduling mechanism is proposed to handle the real-time overload problem by maximizing the cumulative values of three types of tasks： the soft, the hard and the imprecise tasks. The simulation results show that the performance of our presented mechanism in this paper is greatly improved, much better than that of the other three mechanisms： earliest deadline first （EDF）, highest value first （HVF） and highest density first （HDF）, under the same conditions of all nominal loads and task type proportions.
文摘The minimum aperiodic crosscorrelation of binary sequences of size M and length n over the alphabet E={1, -1} has been obtained by Levenshtein for M≥4 and n≥2 These bounds improve a long standing bound given by Welch. In this paper, the Sarwate bounds for codes over the p th roots of unity with the same parameters M and n are discussed, that is,the lower bounds and trade off are established for the maximum magnitude of the aperiodic crosscorrelation function and the maximum magnitude of the out of phase aperiodic autocorrelation function for the sets of periodic sequences with the same parameters M and n by using the modified Levenshtein method. The results show that new bounds are tighter than Sarwate bounds and Levenshtein bounds.
文摘In this article we summarize some aperiodic checkpoint placement algorithms for a software system over infinite and finite operation time horizons, and compare them in terms of computational accuracy. The underlying problem is formulated as the maximization of steady-state system availability and is to determine the optimal aperiodic checkpoint sequence. We present two exact computation algorithms in both forward and backward manners and two approximate ones;constant hazard approximation and fluid approximation, toward this end. In numerical examples with Weibull system failure time distribution, it is shown that the combined algorithm with the fluid approximation can calculate effectively the exact solutions on the optimal aperiodic checkpoint sequence.
基金the financial support from the National Natural Science Foundation of China (No. 11002026, 11372039)Beijing Natural Science Foundation (No. 3133039)the Scientific Research Foundation for the Returned Overseas Chinese Scholars (No. 20121832001)
文摘The localization characteristics of the in-plane elastic waves in locally resonant aperiodic phononic crystals are examined in this study. In particular, the phononic crystals generated according to the Thue-Morse, Rudin-Shapiro and Period-Doubling sequences are theoretically investigated by using the extended transfer matrix method. For comparison, the binary and ternary locally resonant systems are considered, and their band structures are characterized by using the localization factors. Moreover, the influences of structural arrangement, material combination, incidence angle, number of components, length ratio, and random disorder on the band structures are also discussed. Some novel and interesting phenomena are observed and discussed.
文摘This paper addresses the new algebraic test to check the aperiodic stability of two dimensional linear time invariant discrete systems. Initially, the two dimensional characteristics equations are converted into equivalent one-dimensional equation. Further Fuller’s idea is applied on the equivalent one-dimensional characteristics equation. Then using the co-efficient of the characteristics equation, the routh table is formed to ascertain the aperiodic stability of the given two-dimensional linear discrete system. The illustrations were presented to show the applicability of the proposed technique.
基金supported by the 863 Program under Grant No2007AA01Z131
文摘In the previous work of garbage collection （GC） models, scheduling analysis was given based on an assumption that there were no aperiodic mutator tasks. However, it is not true in practical real-time systems. The GC algorithm which can schedule aperiodic tasks is proposed, and the variance of live memory is analyzed. In this algorithm, active tasks are deferred to be processed by GC until the states of tasks become inactive, and the saved sporadic server time can be used to schedule aperiodic tasks. Scheduling the sample task sets demonstrates that this algorithm in this paper can schedule aperiodic tasks and decrease GC work. Thus, the GC algorithm proposed is more flexible and portable.
基金J.J.C.and J.B.thank grant PID2020-118317GB-I00 funded by MICIU/AEI/10.13039/501100011033.
文摘The stability of matter is a historical problem that tackles the linearity of the bulk energy with the total number of particles M.The classical and quantum variants have been proved using mostly Coulomb interaction between electrons and nuclei,either fixed or submitted to thermal fluctuation.The classical dipole–dipole interaction is addressed here as the sole energy on regular tilings.We prove that the system on any regular(periodic)grid is always stable.The aperiodic or quasicrystal instance is conjectured and numerically illustrated for the particular cases of the Penrose P2 and the recently discovered hat monotiles.
基金supported by the Major Project for the Integration of ScienceEducation and Industry (Grant No.2025ZDZX02)。
文摘Classical computation of electronic properties in large-scale materials remains challenging.Quantum computation has the potential to offer advantages in memory footprint and computational scaling.However,general and viable quantum algorithms for simulating large-scale materials are still limited.We propose and implement random-state quantum algorithms to calculate electronic-structure properties of real materials.Using a random state circuit on a small number of qubits,we employ real-time evolution with first-order Trotter decomposition and Hadamard test to obtain electronic density of states,and we develop a modified quantum phase estimation algorithm to calculate real-space local density of states via direct quantum measurements.Furthermore,we validate these algorithms by numerically computing the density of states and spatial distributions of electronic states in graphene,twisted bilayer graphene quasicrystals,and fractal lattices,covering system sizes from hundreds to thousands of atoms.Our results manifest that the random-state quantum algorithms provide a general and qubit-efficient route to scalable simulations of electronic properties in large-scale periodic and aperiodic materials.
