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Time Parameter Based Low-Energy Data Encryption Method for Mobile Applications
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作者 Li-Woei Chen Kun-Lin Tsai +2 位作者 Fang-Yie Leu Wen-Cheng Jiang Shih-Ting Tseng 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第9期2779-2794,共16页
Various mobile devices and applications are now used in daily life.These devices require high-speed data processing,low energy consumption,low communication latency,and secure data transmission,especially in 5G and 6G... Various mobile devices and applications are now used in daily life.These devices require high-speed data processing,low energy consumption,low communication latency,and secure data transmission,especially in 5G and 6G mobile networks.High-security cryptography guarantees that essential data can be transmitted securely;however,it increases energy consumption and reduces data processing speed.Therefore,this study proposes a low-energy data encryption(LEDE)algorithm based on the Advanced Encryption Standard(AES)for improving data transmission security and reducing the energy consumption of encryption in Internet-of-Things(IoT)devices.In the proposed LEDE algorithm,the system time parameter is employed to create a dynamic S-Box to replace the static S-Box of AES.Tests indicated that six-round LEDE encryption achieves the same security level as 10-round conventional AES encryption.This reduction in encryption time results in the LEDE algorithm having a 67.4%lower energy consumption and 43.9%shorter encryption time than conventional AES;thus,the proposed LEDE algorithm can improve the performance and the energy consumption of IoT edge devices. 展开更多
关键词 Mobile application security AES data encryption time parameter mobile device
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A tentative model for the explanation of B?th law using the order parameter of seismicity in natural time 被引量:1
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作者 Konstantina A. Papadopoulou Efthimios S. Skordas Nicholas V. Sarlis 《Earthquake Science》 CSCD 2016年第6期311-319,共9页
Using the order parameter of seismicity defined in natural time, we suggest a simple model for the expla- nation of Bath law, according to which a mainshock differs in magnitude from its largest aftershock by approxim... Using the order parameter of seismicity defined in natural time, we suggest a simple model for the expla- nation of Bath law, according to which a mainshock differs in magnitude from its largest aftershock by approximately 1.2 regardless of the mainshock magnitude. In addition, the validity of Bath law is studied in the Global Centroid Moment Tensor catalogue by using two different aftershock definitions. It is found that the mean of this difference, when considering all the pairs mainshock-largest aftershock, does not markedly differ from 1.2 and the corresponding distributions do not depend on the mainshock's magnitude threshold in a statistically significant manner. Finally, the analysis of the cumulative distribution functions provides evidence in favour of the proposed model. 展开更多
关键词 Bath law . Aftershocks .Order parameter .Natural time
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LMS-LIKE ESTIMATION FOR TIME VARYING PARAMETERS
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作者 陈翰馥 郭雷 张纪峰 《Acta Mathematica Scientia》 SCIE CSCD 1991年第3期327-340,共14页
An LMS-like algorithm is applied for estimating the time-varying parameter theta-n in the linear model y(n) = phi-n-tau-theta-n + upsilon-n, which is general in the sense that none of the probabilistic properties such... An LMS-like algorithm is applied for estimating the time-varying parameter theta-n in the linear model y(n) = phi-n-tau-theta-n + upsilon-n, which is general in the sense that none of the probabilistic properties such as stationarity, Markov property, independence and ergodicity is imposed on any of the processes {y(n)}, {phi-n}, {theta-n} and {upsilon-n}. It is shown that the alpha-th moment of the estimation error is of order of the alpha-th moment of the observation noise and the parameter variation w(n) change in equivalence theta-n - theta-n-1. 展开更多
关键词 LMS-LIKE ESTIMATION FOR TIME VARYING parameterS der Zhang ACTA 石蕊 少司
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TIME DOMAIN PARAMETERS IDENTIFICATION OF FOUNDATION-STRUCTURE INTERACTION SYSTEM
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作者 黄义 刘增荣 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2005年第7期855-864,共10页
The time domain parameter laenuncauon memoa oi me iounuauon-structure interaction system is presented. On the basis of building the computation mode and the motion equation of the foundation-structure interaction syst... The time domain parameter laenuncauon memoa oi me iounuauon-structure interaction system is presented. On the basis of building the computation mode and the motion equation of the foundation-structure interaction system, the system parameter identification method was established by using the extended Kalman filter (EKF) technique and taking the unknown parameters in the system as the augment state variables. And the time parameter identification process of the foundation-structure interaction system was implemented by using the data of the layer foundation-storehouse interaction system model test on the large vibration platform. The computation result shows that the established parameter identification method can induce good parameter estimation. 展开更多
关键词 foundation-structure interaction system time domain parameter identification
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Adaptive Fuzzy Neural Control of Dynamic System
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作者 赵保军 韩月秋 毛二可 《Journal of Beijing Institute of Technology》 EI CAS 1999年第2期85-89,共5页
Aim To build an adaptive fuzzy neural controller and simulate it. Methods\ Fuzzy logic and back propagation(BP) algorithm are combined to utilize their advantages while avoiding the disadvantages. Results and Conclus... Aim To build an adaptive fuzzy neural controller and simulate it. Methods\ Fuzzy logic and back propagation(BP) algorithm are combined to utilize their advantages while avoiding the disadvantages. Results and Conclusion\ Simulation results of the third order plant with disturbances and dead times show the validity of the presented controller. The presented controller can control cases that preceding controllers were unable to control. 展开更多
关键词 error back propagation fuzzy logic learning rate nonlinear time varying parameter
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Optimal Formation Reconfiguration Control of Multiple UCAVs Using Improved Particle Swarm Optimization 被引量:16
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作者 Hai-bin Duan Guan-jun Ma De-lin Luo 《Journal of Bionic Engineering》 SCIE EI CSCD 2008年第4期340-347,共8页
Optimal formation reconfiguration control of multiple Uninhabited Combat Air Vehicles (UCAVs) is a complicated global optimum problem. Particle Swarm Optimization (PSO) is a population based stochastic optimizatio... Optimal formation reconfiguration control of multiple Uninhabited Combat Air Vehicles (UCAVs) is a complicated global optimum problem. Particle Swarm Optimization (PSO) is a population based stochastic optimization technique inspired by social behaviour of bird flocking or fish schooling. PSO can achieve better results in a faster, cheaper way compared with other bio-inspired computational methods, and there are few parameters to adjust in PSO. In this paper, we propose an improved PSO model for solving the optimal formation reconfiguration control problem for multiple UCAVs. Firstly, the Control Parameterization and Time Diseretization (CPTD) method is designed in detail. Then, the mutation strategy and a special mutation-escape operator are adopted in the improved PSO model to make particles explore the search space more efficiently. The proposed strategy can produce a large speed value dynamically according to the variation of the speed, which makes the algorithm explore the local and global minima thoroughly at the same time. Series experimental results demonstrate the feasibility and effectiveness of the proposed method in solving the optimal formation reconfiguration control problem for multiple UCAVs. 展开更多
关键词 uninhabited combat air vehicles particle swarm optimization control parameterization and time discretization optimal formation reeonfiguration
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Performance analysis model for real-time Ethernet-based computer numerical control system 被引量:2
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作者 万加富 李迪 +1 位作者 涂钰青 张春华 《Journal of Central South University》 SCIE EI CAS 2011年第5期1545-1553,共9页
In order to optimize the embedded system implementation for Ethernet-based computer numerical control (CNC) system, it is very necessary to establish the performance analysis model and further adopt the codesign met... In order to optimize the embedded system implementation for Ethernet-based computer numerical control (CNC) system, it is very necessary to establish the performance analysis model and further adopt the codesign method from the control, communication and computing perspectives. On the basis of analyzing real-time Ethemet, system architecture, time characteristic parameters of control-loop ere, a performance analysis model for real-time Ethemet-based CNC system was proposed, which is able to include the timing effects caused by the implementation platform in the simulation. The key for establishing the model is accomplished by designing the error analysis module and the controller nodes. Under the restraint of CPU resource and communication bandwidth, the experiment with a case study was conducted, and the results show that if the deadline miss ratio of data packets is 0.2%, then the percentage error is 1.105%. The proposed model can be used at several stages of CNC system development. 展开更多
关键词 computer numerical control (CNC) system real-time Ethemet time characteristic parameters performance analysis model manufacturing accuracy
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Time variant multi-objective linear fractional interval-valued transportation problem 被引量:1
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作者 Dharmadas Mardanya Sankar Kumar Roy 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2022年第1期111-130,共20页
This paper studies a time-variant multi-objective linear fractional transportation problem. In reality, transported goods should reach in destinations within a specific time. Considering the importance of time, a time... This paper studies a time-variant multi-objective linear fractional transportation problem. In reality, transported goods should reach in destinations within a specific time. Considering the importance of time, a time-variant multi-objective linear fractional transportation problem is formulated here. We take into account the parameters as cost, supply and demand are interval valued that involved in the proposed model, so we treat the model as a multi-objective linear fractional interval transportation problem. To solve the formulated model, we first convert it into a deterministic form using a new transformation technique and then apply fuzzy programming to solve it. The applicability of our proposed method is shown by considering two numerical examples. At last, conclusions and future research directions regarding our study is included. 展开更多
关键词 fractional transportation problem multi-objective optimization interval number time variant parameter fuzzy programming Pareto optimal solution
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Uncertainty Assessment of Soil Erosion Model Using Particle Filtering
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作者 Yeonsu KIM Giha LEE +1 位作者 Hyunuk AN Jae E YANG 《Journal of Mountain Science》 SCIE CSCD 2015年第4期828-840,共13页
Recent advances in computer with geographic information system(GIS) technologies have allowed modelers to develop physics-based models for modeling soil erosion processes in time and space.However, it has been widely ... Recent advances in computer with geographic information system(GIS) technologies have allowed modelers to develop physics-based models for modeling soil erosion processes in time and space.However, it has been widely recognized that the effect of uncertainties on model predictions may be more significant when modelers apply such models for their own modeling purposes.Sources of uncertainty involved in modeling include data, model structural, and parameter uncertainty.To deal with the uncertain parameters of a catchment-scale soil erosion model(CSEM) and assess simulation uncertainties in soil erosion, particle filtering modeling(PF) is introduced in the CSEM.The proposed method, CSEM-PF, estimates parameters of non-linear and non-Gaussian systems, such as a physics-based soil erosion model by assimilating observation data such as discharge and sediment discharge sequences at outlets.PF provides timevarying feasible parameter sets as well as uncertainty bounds of outputs while traditional automatic calibration techniques result in a time-invariant global optimal parameter set.CSEM-PF was applied to a small mountainous catchment of the Yongdamdam in Korea for soil erosion modeling and uncertainty assessment for three historical typhoon events.Finally, the most optimal parameter sets and uncertainty bounds of simulation of both discharge and sediment discharge at each time step of the study events are provided. 展开更多
关键词 Data assimilation Particle filter Soil erosion modeling parameter estimation Time variant parameter Mountainous catchment
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Ehrenfest Approach to the Adiabatic Invariants and Calculation of the Intervals of Time Entering the Energy Emission Process in Simple Quantum Systems 被引量:1
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作者 Stanislaw Olszewski 《Journal of Quantum Information Science》 2020年第1期1-9,共9页
In the first step, the Ehrenfest reasoning concerning the adiabatic invariance of the angular orbital momentum is applied to the electron motion in the hydrogen atom. It is demonstrated that the time of the energy emi... In the first step, the Ehrenfest reasoning concerning the adiabatic invariance of the angular orbital momentum is applied to the electron motion in the hydrogen atom. It is demonstrated that the time of the energy emission from the quantum level n+1 to level n can be deduced from the orbital angular momentum examined in the hydrogen atom. This time is found precisely equal to the time interval dictated by the Joule-Lenz law governing the electron transition between the levels n+1 and n. In the next step, the mechanical parameters entering the quantum systems are applied in calculating the time intervals characteristic for the electron transitions. This concerns the neighbouring energy levels in the hydrogen atom as well as the Landau levels in the electron gas submitted to the action of a constant magnetic field. 展开更多
关键词 Aadiabatic Invariants Time of the Energy Emission Process Referred to the Mechanical parameters of a Quantum System Hydrogen Atom The Landau Levels in the Electron Gas
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Adaptive bolus chasing computed tomography angiography by a local linear time and space parameter varying model:modeling,control,identification,and experimental results
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作者 Zhijun CAI Ge WANG Er-Wei BAI 《Frontiers of Electrical and Electronic Engineering in China》 CSCD 2010年第2期119-127,共9页
A high contrast to noise ratio(CNR)is always desirable for contrast-enhanced computed tomography angiography(CTA).To ensure a high CNR of the vascular images in CTA and potentially reduce the radiation exposure and co... A high contrast to noise ratio(CNR)is always desirable for contrast-enhanced computed tomography angiography(CTA).To ensure a high CNR of the vascular images in CTA and potentially reduce the radiation exposure and contrast usage,an adaptive bolus chasing method is proposed and evaluated compared to the existing constant-speed method.The proposed method is based on a local time and space parameter varying model of the contrast bolus.Optimal scan time for the next segment of the vasculature is estimated and predicted in real time and guides the computed tomography(CT)scanner table movement that guarantees that each segment of the vasculature is scanned with the maximum possible enhancement.Simulations and experimental results show that the proposed bolus chasing method outperforms the conventional constant-speed method substantially. 展开更多
关键词 adaptive control bolus chasing computed tomography angiography(CTA) local linear time and space parameter varying model
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Robust Load Frequency Control for Isolated Microgrids Based on Double-loop Compensation 被引量:1
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作者 Yang Mi Yuchen Ma +5 位作者 Xingtang He Xingwu Yang Jinxia Gong Yao Zhao Ronghui Liu Wei Wei 《CSEE Journal of Power and Energy Systems》 SCIE EI CSCD 2023年第4期1359-1369,共11页
Frequency is an important indicator for the oper-ation of microgrids.However,the randomness and uncertainty of renewable energy and load variability may lead to frequency undulation.So,a robust load frequency control(... Frequency is an important indicator for the oper-ation of microgrids.However,the randomness and uncertainty of renewable energy and load variability may lead to frequency undulation.So,a robust load frequency control(LFC)is pro-posed for isolated wind-diesel microgrids considering time delay and parameter uncertainty.The control strategy can suppress frequency fuctuation and optimize frequency dynamic response.First,the double compensation loop,including feedforward control and integral sliding mode control(SMC),is devised to provide anti-disturbance compensation for the diesel generator system and ameliorate the frequency stability of independent microgrids.Secondly,a dynamic fuzzy controller,composed of wind speed and load demand,is designed to provide real-time response reference power for doubly fed induction generator systems(DFIGs),which can promote the effective participation of a wind turbine system for frequency regulation.Then,the proportional differential(PD)parameters of a dynamic fuzzy controller and the frequency adjustment compensation of DFIGs can be obtained by using a particle swarm optimization(PSO)algorithm.Thirdly,load demand is an important index of the robust dynamic load frequency control method;the radial basis function(RBF)neural network observer(NNO)based on the LFC model is presented to obtain more accurate load deviations and improve the control precision of LFC.The performance of the proposed LFC method is tested under different operation cases.Index Terms-Load frequency control,microgrid,neural network observer,sliding mode,time delay and parameter uncertainty. 展开更多
关键词 Load frequency control MICROGRID neural network observer sliding mode time delay and parameter uncertainty.
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