Bastd on the relationship between nonlinearity and resiliency of amulti-output function, we present a method for constructing noninterseeling linear codes frompacking design. Through these linear codes, we obtain n-va...Bastd on the relationship between nonlinearity and resiliency of amulti-output function, we present a method for constructing noninterseeling linear codes frompacking design. Through these linear codes, we obtain n-variable, m-output, t-resilient functionswith very high nonlinearity. Their nonlinearities are currently the best results for most of cases.展开更多
Due to the increasing interests in using functionally graded piezoelectric materials(FGPMs) in the design of advanced micro-electro-mechanical systems, it is important to understand the stability behaviors of the FGPM...Due to the increasing interests in using functionally graded piezoelectric materials(FGPMs) in the design of advanced micro-electro-mechanical systems, it is important to understand the stability behaviors of the FGPM beams. In this study, considering the effects of geometrical nonlinearity, temperature, and electricity in the constitutive relations and the effect of the magnetic field on the FGPM beam, the Euler-Bernoulli beam model is adopted, and the nonlinear governing equation of motion is derived via Hamilton's principle. A perturbation method, which can decompose the deflection into static and dynamic components, is utilized to linearize the nonlinear governing equation. Then,a dynamic stability analysis is carried out, and the approximate analytical solutions for the nonlinear frequency and boundary frequencies of the unstable region are obtained.Numerical examples are performed to verify the present analysis. The effects of the static deflection, the static load factor, the temperature change, and the magnetic field flux on the stability behaviors of the FGPM beam are discussed. From the proposed analytical solutions and numerical results, one can easily and clearly find the effects of various controlled parameters, such as geometric and physical properties of the system, on the mechanical behaviors of structures, and the conclusions are very important and useful for the design of micro-devices.展开更多
The nonlinearity of functionalized and nonfunctionlaized graphene as well as gold nanorods were investigated using the Z-scan system with an Ar＋ laser beam tuned at a wavelength of 514 nm in a CW （continuous wave） ...The nonlinearity of functionalized and nonfunctionlaized graphene as well as gold nanorods were investigated using the Z-scan system with an Ar＋ laser beam tuned at a wavelength of 514 nm in a CW （continuous wave） regime that was in resonance with AuNRs （gold nanorods）. Z-scan experimental study indicated that functionalized graphene had a negative nonlinear refraction with self-defocusing performance. The result concluded that gold nanorods （average length was 36 ± 3 nm, and the average diameter was 12 ± 2 nm） enhance the thermal nonlinear properties of graphene oxide materials. Gold nanorods were proved to enhance the nonlinear absorption by 50%, and there was a large enhancement on the thermal nonlinear refraction and the thermo-optical coefficient （dn/dT）. It was observed that the AuFG （functionalized graphene film with gold nanorods） presented a large thermal nonlinear refraction. The value of the nonlinear refraction （nl＇） of FG and AuFG samples was shifted from -0.533 x 10.7 cm2/W to -2.92 x 10-7 cm2/W. There was a large enhancement in thermal refraction value that was about five factors larger than the nonlinear refraction of the host material （FG） and much larger （4 orders of magnitude） than that for AuNRs.展开更多
In this paper,we investigate nonlinear the perturbed nonlinear Schrdinger's equation (NLSE) with Kerr law nonlinearity given in [Z.Y.Zhang,et al.,Appl.Math.Comput.216 (2010) 3064] and obtain exact traveling soluti...In this paper,we investigate nonlinear the perturbed nonlinear Schrdinger's equation (NLSE) with Kerr law nonlinearity given in [Z.Y.Zhang,et al.,Appl.Math.Comput.216 (2010) 3064] and obtain exact traveling solutions by using infinite series method (ISM),Cosine-function method (CFM).We show that the solutions by using ISM and CFM are equal.Finally,we obtain abundant exact traveling wave solutions of NLSE by using Jacobi elliptic function expansion method (JEFEM).展开更多
This paper deals with the nonlinear large deflection analysis of functionally graded carbon nanotube-reinforced composite(FG-CNTRC)plates and panels using a finite element method.Based on the first-order shear deforma...This paper deals with the nonlinear large deflection analysis of functionally graded carbon nanotube-reinforced composite(FG-CNTRC)plates and panels using a finite element method.Based on the first-order shear deformation theory(FSDT),the proposed model takes into account the transverse shear deformations and incorporates the geometrical nonlinearity type.A C^0 isoparametric finite shell element is developed for the present nonlinear model with the description of large displacements and finite rotations.By adopting the extended rule of mixture,the effective material properties of FG-CNTRCs are approximated with the introduction of some efficiency parameters.Four carbon nanotube(CNT)distributions,labeled uniformly distributed(UD)-CNT,FG-VCNT,FG-O-CNT,and FG-X-CNT,are considered.The solution procedure is carried out via the Newton-Raphson incremental technique.Various numerical applications in both isotropic and CNTRC composite cases are performed to trace the potential of the present model.The effects of the CNT distributions,their volume fractions,and the geometrical characteristics on the nonlinear deflection responses of FG-CNTRC structures are highlighted via a detailed parametric study.展开更多
This paper presents an integrated guidance and control model for a flexible hypersonic vehicle with terminal angular constraints.The integrated guidance and control model is bounded and the dead-zone input nonlinearit...This paper presents an integrated guidance and control model for a flexible hypersonic vehicle with terminal angular constraints.The integrated guidance and control model is bounded and the dead-zone input nonlinearity is considered in the system dynamics.The line of sight angle,line of sight angle rate,attack angle and pitch rate are involved in the integrated guidance and control system.The controller is designed with a backstepping method,in which a first order filter is employed to avoid the differential explosion.The full tuned radial basis function(RBF)neural network(NN)is used to approximate the system dynamics with robust item coping with the reconstruction errors,the exactitude model requirement is reduced in the controller design.In the last step of backstepping method design,the adaptive control with Nussbaum function is used for the unknown dynamics with a time-varying control gain function.The uniform ultimate boundedness stability of the control system is proved.The simulation results validate the effectiveness of the controller design.展开更多
This paper presents a construction for a class of 1-resilient functions with optimal algebraic immunity on an even number of variables. The construction is based on the concatenation of two balanced functions in assoc...This paper presents a construction for a class of 1-resilient functions with optimal algebraic immunity on an even number of variables. The construction is based on the concatenation of two balanced functions in associative classes. For some n, a part of 1-resilient functions with maximum algebraic immunity constructed in the paper can achieve almost optimal nonlinearity. Apart from their high nonlinearity, the functions reach Siegenthaler＇s upper bound of algebraic degree. Also a class of l-resilient functions on any number n 〉 2 of variables with at least sub-optimal algebraic immunity is provided.展开更多
Carlet et al. recently introduced generalized nonlinearity to measure the ability to resist the improved correlation attack of a vector output Boolean function. This article presents a construction of vector output Bo...Carlet et al. recently introduced generalized nonlinearity to measure the ability to resist the improved correlation attack of a vector output Boolean function. This article presents a construction of vector output Boolean fimctions with high generalized nonlinearity using the e-biased sample space. The relation between the resilient order and generalized nonlinearity is also discussed.展开更多
Boolean functions possessing multiple cryptographic criteria play an important role in the design of symmetric cryptosystems. The following criteria for cryptographic Boolean functions are often considered： high nonl...Boolean functions possessing multiple cryptographic criteria play an important role in the design of symmetric cryptosystems. The following criteria for cryptographic Boolean functions are often considered： high nonlinearity, balancedness, strict avalanche criterion, and global avalanche characteristics. The trade-off among these criteria is a difficult problem and has attracted many researchers. In this paper, two construction methods are provided to obtain balanced Boolean functions with high nonlinearity. Besides, the constructed functions satisfy strict avalanche criterion and have good global avalanche characteristics property. The algebraic immunity of the constructed functions is also considered.展开更多
The main results in this paper are to construct two classes of plateaued functions with desirable cryptographic properties. By using the Maiorana-McFarland construction, a class of highly nonlinear resilient plateaued...The main results in this paper are to construct two classes of plateaued functions with desirable cryptographic properties. By using the Maiorana-McFarland construction, a class of highly nonlinear resilient plateaued functions satisfying the propagation criterion has been obtained. Johansson,s et al＇ s construction is modified slightly to obtain highly nonlinear multi-output resilient plateaued functions.展开更多
Dear Editor,This letter deals with the stabilization of a resilient model predictive control(MPC)algorithm with a dynamic event-triggered mechanism subject to Denial-of-Service(Do S)attacks.Different from previous wor...Dear Editor,This letter deals with the stabilization of a resilient model predictive control(MPC)algorithm with a dynamic event-triggered mechanism subject to Denial-of-Service(Do S)attacks.Different from previous works,this letter is based on the designed threshold function to dynamically trigger and gives the upper bound conditions for intersampling intervals with attack and attack-free scenarios to converge.展开更多
This study was carried out to assess plasticity to drought of 30 adult fig cultivars,based on a screening of leaf structural and functional traits under sustained deficit irrigation,corresponding to 60%of crop evapotr...This study was carried out to assess plasticity to drought of 30 adult fig cultivars,based on a screening of leaf structural and functional traits under sustained deficit irrigation,corresponding to 60%of crop evapotranspiration.All trees,three per cultivar,are planted in an ex-situ collection in Sais plain,northern Morocco.The measurements concerned leaf area,blade thickness,trichomes density,trichome hair length,stomatal density,stomatal dimensions,stomatal area index,chlorophyll concentration index,relative water content,stomatal conductance,leaf temperature,water loss in detached leaves,cuticular wax content,proline content,total phenolic compounds,and total soluble sugars.The ranking of cultivars regarding drought tolerance was established based on a two-level clustering approach,primarily relying on chlorophyll concentration index and secondarily on water status traits.Results showed significant genotypic variations for all measured traits,except phenolic compounds content.Correlations between structural and functional traits have pinpointed blade thickness and trichome hair length as the key indicators of fig drought tolerance,owing to their involvement in maintaining chlorophyll content under water stress conditions.The extent of the variations shows that fig leaf is endowed with a wide structural and functional diversity,which can give to the species potential for resilience to various environmental stresses,including drought.Among the cultivars assessed,two exotic varieties,“Kadota”and“Royal Blanck”,as well as four local cultivars,namely,“Ferqouch Jmel”,“El Qoti Labied”,“Hamra”and“Fassi”showed the highest drought plasticity level.展开更多
This study investigates the nonlinear dynamic properties of rotating functionally graded sandwich rectangular plates in a thermal environment.The nonlinear vibration equations for a rotating metal-ceramic functionally...This study investigates the nonlinear dynamic properties of rotating functionally graded sandwich rectangular plates in a thermal environment.The nonlinear vibration equations for a rotating metal-ceramic functionally graded sandwich rectangular plate in a thermal environment are derived using classical thin plate theory and Hamilton’s principle,considering geometric nonlinearity,temperature-dependent material properties,and power law distribution of components through the thickness.With cantilever boundary conditions,the flexural nonlinear differential equations of the rectangular sandwich plate are obtained via the Galerkin method.Since the natural vibration differential equations exhibit nonlinear characteristics,the multiscale method is employed to derive the expression for nonlinear natural frequency.An example analysis reveals how the natural frequency of a functionally graded sandwich rectangular plate varies with rotational speed and temperature.Results show that the nonlinear/linear frequency ratio increases with rotational angular velocity Ω and thickness-to-length ratio h/a,follows a cosine-like periodic pattern with the setting angle,and shows a sharp decrease followed by a rapid increase with increasing width-to-length ratio b/a.The derived analytical solutions for nonlinear frequency provide valuable insights for assessing the dynamic characteristics of functionally graded structures.展开更多
Based on the superiority of adaptive filtering algorithms designed with hyperbolic function-like objective functions,this paper proposes generalized spline adaptive filtering(SAF)algorithms designed with hyperbolic fu...Based on the superiority of adaptive filtering algorithms designed with hyperbolic function-like objective functions,this paper proposes generalized spline adaptive filtering(SAF)algorithms designed with hyperbolic function-like objective functions.Specifically,a series of generalized new SAF algorithms are proposed by introducing the q-deformed hyperbolic function as the cost function,named SAF-qDHSI,SAF-qDHCO,SAFqDHTA&SAF-qDHSE algorithms,respectively.Then,the proposed algorithm is theoretically demonstrated with detailed mean convergence and computational complexity analysis;secondly,the effect of different q values on the performance of the new algorithm is verified through data simulation;the new algorithm still has better performance under the interference of Gaussian noise and non-Gaussian noise even when facing the system mutation;finally,the new algorithm is verified through the measured engineering data,and the results show that the new algorithm has better convergence and robustness compared with the existing algorithm.In conclusion,the generalized algorithm based on the new cost function proposed in this paper is more effective in nonlinear system identification.展开更多
The nonlinear traveling wave vibration of rotating ferromagnetic functionally graded(FG)cylindrical shells under multi-physics fields is investigated.Grounded in the Kirchhoff-Love thin shell theory,the geometric nonl...The nonlinear traveling wave vibration of rotating ferromagnetic functionally graded(FG)cylindrical shells under multi-physics fields is investigated.Grounded in the Kirchhoff-Love thin shell theory,the geometric nonlinearity is incorporated into the model,and the constitutive equations are derived.The physical parameters of functionally graded materials(FGMs),which exhibit continuous variation across the thickness gradient,are of particular interest.The nonlinear magneto-thermoelastic governing equations are derived in accord with Hamilton's principle.The nonlinear partial differential equations are discretized with the Galerkin method,and the analytical expression of traveling wave frequencies is derived with an approximate method.The accuracy of the proposed method is validated through the comparison with the results from the literature and numerical solutions.Finally,the visualization analyses are conducted to examine the effects of key parameters on the traveling wave frequencies.The results show that the factors including the power-law index,temperature,magnetic field intensity,and rotating speed have the coupling effects with respect to the nonlinear vibration behavior.展开更多
For an odd integer n ≥ 7, this paper presented a class of n-variable rotation symmetric Boolean functions （RSBFs） with optimum algebraic immunity. The nonlinearity of the constructed functions is determined.
Horizontal impedance functions of inclined single piles are measured experimentally for model soil-pile systems with both the effects of local soil nonlinearity and resonant characteristics.Two practical pile inclinat...Horizontal impedance functions of inclined single piles are measured experimentally for model soil-pile systems with both the effects of local soil nonlinearity and resonant characteristics.Two practical pile inclinations of 5掳 and 10掳 in addition to a vertical pile embedded in cohesionless soil and subjected to lateral harmonic pile head loadings for a wide range of frequencies are considered.Results obtained with low-to-high amplitude of lateral loadings on model soil-pile systems encased in a laminar shear box show that the local nonlinearities have a profound impact on the horizontal impedance functions of piles.Horizontal impedance functions of inclined piles are found to be smaller than the vertical pile and the values decrease as the angle of pile inclination increases.Distinct values of horizontal impedance functions are obtained for the ＇positive＇ and ＇negative＇ cycles of harmonic loadings,leading to asymmetric force-displacement relationships for the inclined piles.Validation of these experimental results is carried out through three-dimensional nonlinear finite element analyses,and the results from the numerical models are in good agreement with the experimental data.Sensitivity analyses conducted on the numerical models suggest that the consideration of local nonlinearity at the vicinity of the soil-pile interface influence the response of the soil-pile systems.展开更多
This paper discusses the degree of completeness of cryptographic functions, which is one of the cryptographic criteria should be considered in the design of stream ciphers. We establish the relationships between the d...This paper discusses the degree of completeness of cryptographic functions, which is one of the cryptographic criteria should be considered in the design of stream ciphers. We establish the relationships between the degree of completeness and other cryptographic criteria. For resilient Boolean functions, a method to enhance the degree of completeness is proposed, while the nonlinearity and the algebraic degree do not decrease. Moreover, two constructions of resilient functions are provided, which have optimal degree of completeness, high nonlinearity, and high algebraic degree.展开更多
Any single Positioning,Navigation and Timing(PNT)technology has its vulnerability and limits,even the powerful Global Navigation Satellite System(GNSS)is no exception.To provide continuous and reliable PNT information...Any single Positioning,Navigation and Timing(PNT)technology has its vulnerability and limits,even the powerful Global Navigation Satellite System(GNSS)is no exception.To provide continuous and reliable PNT information to users,the theory and technique of comprehensive PNT information system and resilient PNT application system have attracted great attention from Chinese scholars.We try to summarize the progress and development of the synthetic PNT system,including the proposal,the modification and the improvement of the comprehensive PNT,as well as the follow-up resilient PNT.The frame of China’s comprehensive PNT system consisted of comprehensive PNT infrastructure and comprehensive PNT application system is initially described;the achievements on some main PNT technologies are introduced;the conceptual models of resilient PNT are given;besides,existing researches on resilient function models and stochastic models are summarized according to different user scenarios.展开更多
文摘Bastd on the relationship between nonlinearity and resiliency of amulti-output function, we present a method for constructing noninterseeling linear codes frompacking design. Through these linear codes, we obtain n-variable, m-output, t-resilient functionswith very high nonlinearity. Their nonlinearities are currently the best results for most of cases.
基金Project supported by the National Natural Science Foundation of China(No.11802319)the National Key Research and Development Program of China(No.2017YFB1102801)。
文摘Due to the increasing interests in using functionally graded piezoelectric materials(FGPMs) in the design of advanced micro-electro-mechanical systems, it is important to understand the stability behaviors of the FGPM beams. In this study, considering the effects of geometrical nonlinearity, temperature, and electricity in the constitutive relations and the effect of the magnetic field on the FGPM beam, the Euler-Bernoulli beam model is adopted, and the nonlinear governing equation of motion is derived via Hamilton's principle. A perturbation method, which can decompose the deflection into static and dynamic components, is utilized to linearize the nonlinear governing equation. Then,a dynamic stability analysis is carried out, and the approximate analytical solutions for the nonlinear frequency and boundary frequencies of the unstable region are obtained.Numerical examples are performed to verify the present analysis. The effects of the static deflection, the static load factor, the temperature change, and the magnetic field flux on the stability behaviors of the FGPM beam are discussed. From the proposed analytical solutions and numerical results, one can easily and clearly find the effects of various controlled parameters, such as geometric and physical properties of the system, on the mechanical behaviors of structures, and the conclusions are very important and useful for the design of micro-devices.
文摘The nonlinearity of functionalized and nonfunctionlaized graphene as well as gold nanorods were investigated using the Z-scan system with an Ar＋ laser beam tuned at a wavelength of 514 nm in a CW （continuous wave） regime that was in resonance with AuNRs （gold nanorods）. Z-scan experimental study indicated that functionalized graphene had a negative nonlinear refraction with self-defocusing performance. The result concluded that gold nanorods （average length was 36 ± 3 nm, and the average diameter was 12 ± 2 nm） enhance the thermal nonlinear properties of graphene oxide materials. Gold nanorods were proved to enhance the nonlinear absorption by 50%, and there was a large enhancement on the thermal nonlinear refraction and the thermo-optical coefficient （dn/dT）. It was observed that the AuFG （functionalized graphene film with gold nanorods） presented a large thermal nonlinear refraction. The value of the nonlinear refraction （nl＇） of FG and AuFG samples was shifted from -0.533 x 10.7 cm2/W to -2.92 x 10-7 cm2/W. There was a large enhancement in thermal refraction value that was about five factors larger than the nonlinear refraction of the host material （FG） and much larger （4 orders of magnitude） than that for AuNRs.
基金Supported by the Research Foundation of Education Bureau of Hunan Province under Grant No.11C0628Foundation of Hunan Institute of Science and Technology under Grant No.2011Y49
文摘In this paper,we investigate nonlinear the perturbed nonlinear Schrdinger's equation (NLSE) with Kerr law nonlinearity given in [Z.Y.Zhang,et al.,Appl.Math.Comput.216 (2010) 3064] and obtain exact traveling solutions by using infinite series method (ISM),Cosine-function method (CFM).We show that the solutions by using ISM and CFM are equal.Finally,we obtain abundant exact traveling wave solutions of NLSE by using Jacobi elliptic function expansion method (JEFEM).
文摘This paper deals with the nonlinear large deflection analysis of functionally graded carbon nanotube-reinforced composite(FG-CNTRC)plates and panels using a finite element method.Based on the first-order shear deformation theory(FSDT),the proposed model takes into account the transverse shear deformations and incorporates the geometrical nonlinearity type.A C^0 isoparametric finite shell element is developed for the present nonlinear model with the description of large displacements and finite rotations.By adopting the extended rule of mixture,the effective material properties of FG-CNTRCs are approximated with the introduction of some efficiency parameters.Four carbon nanotube(CNT)distributions,labeled uniformly distributed(UD)-CNT,FG-VCNT,FG-O-CNT,and FG-X-CNT,are considered.The solution procedure is carried out via the Newton-Raphson incremental technique.Various numerical applications in both isotropic and CNTRC composite cases are performed to trace the potential of the present model.The effects of the CNT distributions,their volume fractions,and the geometrical characteristics on the nonlinear deflection responses of FG-CNTRC structures are highlighted via a detailed parametric study.
文摘This paper presents an integrated guidance and control model for a flexible hypersonic vehicle with terminal angular constraints.The integrated guidance and control model is bounded and the dead-zone input nonlinearity is considered in the system dynamics.The line of sight angle,line of sight angle rate,attack angle and pitch rate are involved in the integrated guidance and control system.The controller is designed with a backstepping method,in which a first order filter is employed to avoid the differential explosion.The full tuned radial basis function(RBF)neural network(NN)is used to approximate the system dynamics with robust item coping with the reconstruction errors,the exactitude model requirement is reduced in the controller design.In the last step of backstepping method design,the adaptive control with Nussbaum function is used for the unknown dynamics with a time-varying control gain function.The uniform ultimate boundedness stability of the control system is proved.The simulation results validate the effectiveness of the controller design.
基金supported by the National Natural Science Foundations of China under Grant Nos. 60903200,61003299
文摘This paper presents a construction for a class of 1-resilient functions with optimal algebraic immunity on an even number of variables. The construction is based on the concatenation of two balanced functions in associative classes. For some n, a part of 1-resilient functions with maximum algebraic immunity constructed in the paper can achieve almost optimal nonlinearity. Apart from their high nonlinearity, the functions reach Siegenthaler＇s upper bound of algebraic degree. Also a class of l-resilient functions on any number n 〉 2 of variables with at least sub-optimal algebraic immunity is provided.
基金the National Natural Science Foundation of China (90604023)Fujian Province Young Talent Program (2006F3044)+2 种基金Natural Science Foundation of Fujian Province (2006J0189)the Open Funds of Key Laboratory of Fujian Province University Network Security and Cryptology (07B002)Fujian Education Department Technology Program (JA07050)
文摘Carlet et al. recently introduced generalized nonlinearity to measure the ability to resist the improved correlation attack of a vector output Boolean function. This article presents a construction of vector output Boolean fimctions with high generalized nonlinearity using the e-biased sample space. The relation between the resilient order and generalized nonlinearity is also discussed.
基金This work was supported in part by the National Natural Science Foundation of China （Grant Nos. 61373008, 11201359, 61562069）, the Natural Science Basic Research Plan in Shaanxi Province of China （Grant No. 2012JM8013）, the 111 Project （Grant No. B08038）, and the Science and Technology on Communication Security Laboratory （Grant No. 9140C110203140C11049）.
文摘Boolean functions possessing multiple cryptographic criteria play an important role in the design of symmetric cryptosystems. The following criteria for cryptographic Boolean functions are often considered： high nonlinearity, balancedness, strict avalanche criterion, and global avalanche characteristics. The trade-off among these criteria is a difficult problem and has attracted many researchers. In this paper, two construction methods are provided to obtain balanced Boolean functions with high nonlinearity. Besides, the constructed functions satisfy strict avalanche criterion and have good global avalanche characteristics property. The algebraic immunity of the constructed functions is also considered.
基金Supported by the National Natural Science Foundations of China （No. 60773003, 60970120, 60903180）, the Natural Science Basic Research Plan in Shanx/Province of China （No. S JOB -ZTI4 ）, and the Fundamental Research Funds For the Central Universities and the 111 Project （ No. B08038 ）.
文摘The main results in this paper are to construct two classes of plateaued functions with desirable cryptographic properties. By using the Maiorana-McFarland construction, a class of highly nonlinear resilient plateaued functions satisfying the propagation criterion has been obtained. Johansson,s et al＇ s construction is modified slightly to obtain highly nonlinear multi-output resilient plateaued functions.
文摘Dear Editor,This letter deals with the stabilization of a resilient model predictive control(MPC)algorithm with a dynamic event-triggered mechanism subject to Denial-of-Service(Do S)attacks.Different from previous works,this letter is based on the designed threshold function to dynamically trigger and gives the upper bound conditions for intersampling intervals with attack and attack-free scenarios to converge.
文摘This study was carried out to assess plasticity to drought of 30 adult fig cultivars,based on a screening of leaf structural and functional traits under sustained deficit irrigation,corresponding to 60%of crop evapotranspiration.All trees,three per cultivar,are planted in an ex-situ collection in Sais plain,northern Morocco.The measurements concerned leaf area,blade thickness,trichomes density,trichome hair length,stomatal density,stomatal dimensions,stomatal area index,chlorophyll concentration index,relative water content,stomatal conductance,leaf temperature,water loss in detached leaves,cuticular wax content,proline content,total phenolic compounds,and total soluble sugars.The ranking of cultivars regarding drought tolerance was established based on a two-level clustering approach,primarily relying on chlorophyll concentration index and secondarily on water status traits.Results showed significant genotypic variations for all measured traits,except phenolic compounds content.Correlations between structural and functional traits have pinpointed blade thickness and trichome hair length as the key indicators of fig drought tolerance,owing to their involvement in maintaining chlorophyll content under water stress conditions.The extent of the variations shows that fig leaf is endowed with a wide structural and functional diversity,which can give to the species potential for resilience to various environmental stresses,including drought.Among the cultivars assessed,two exotic varieties,“Kadota”and“Royal Blanck”,as well as four local cultivars,namely,“Ferqouch Jmel”,“El Qoti Labied”,“Hamra”and“Fassi”showed the highest drought plasticity level.
基金supported by the National Natural Science Foundation of China(No.11772090).
文摘This study investigates the nonlinear dynamic properties of rotating functionally graded sandwich rectangular plates in a thermal environment.The nonlinear vibration equations for a rotating metal-ceramic functionally graded sandwich rectangular plate in a thermal environment are derived using classical thin plate theory and Hamilton’s principle,considering geometric nonlinearity,temperature-dependent material properties,and power law distribution of components through the thickness.With cantilever boundary conditions,the flexural nonlinear differential equations of the rectangular sandwich plate are obtained via the Galerkin method.Since the natural vibration differential equations exhibit nonlinear characteristics,the multiscale method is employed to derive the expression for nonlinear natural frequency.An example analysis reveals how the natural frequency of a functionally graded sandwich rectangular plate varies with rotational speed and temperature.Results show that the nonlinear/linear frequency ratio increases with rotational angular velocity Ω and thickness-to-length ratio h/a,follows a cosine-like periodic pattern with the setting angle,and shows a sharp decrease followed by a rapid increase with increasing width-to-length ratio b/a.The derived analytical solutions for nonlinear frequency provide valuable insights for assessing the dynamic characteristics of functionally graded structures.
基金financially supported by the National Natural Science Foundation of China (8225041038)the Sichuan Science and Technology Program (23NSFSC2916)the Fundamental Research Funds for the Central Universities, Southwest Minzu University (ZYN2024077)
文摘Based on the superiority of adaptive filtering algorithms designed with hyperbolic function-like objective functions,this paper proposes generalized spline adaptive filtering(SAF)algorithms designed with hyperbolic function-like objective functions.Specifically,a series of generalized new SAF algorithms are proposed by introducing the q-deformed hyperbolic function as the cost function,named SAF-qDHSI,SAF-qDHCO,SAFqDHTA&SAF-qDHSE algorithms,respectively.Then,the proposed algorithm is theoretically demonstrated with detailed mean convergence and computational complexity analysis;secondly,the effect of different q values on the performance of the new algorithm is verified through data simulation;the new algorithm still has better performance under the interference of Gaussian noise and non-Gaussian noise even when facing the system mutation;finally,the new algorithm is verified through the measured engineering data,and the results show that the new algorithm has better convergence and robustness compared with the existing algorithm.In conclusion,the generalized algorithm based on the new cost function proposed in this paper is more effective in nonlinear system identification.
基金supported by the National Natural Science Foundation of China(No.12172321)。
文摘The nonlinear traveling wave vibration of rotating ferromagnetic functionally graded(FG)cylindrical shells under multi-physics fields is investigated.Grounded in the Kirchhoff-Love thin shell theory,the geometric nonlinearity is incorporated into the model,and the constitutive equations are derived.The physical parameters of functionally graded materials(FGMs),which exhibit continuous variation across the thickness gradient,are of particular interest.The nonlinear magneto-thermoelastic governing equations are derived in accord with Hamilton's principle.The nonlinear partial differential equations are discretized with the Galerkin method,and the analytical expression of traveling wave frequencies is derived with an approximate method.The accuracy of the proposed method is validated through the comparison with the results from the literature and numerical solutions.Finally,the visualization analyses are conducted to examine the effects of key parameters on the traveling wave frequencies.The results show that the factors including the power-law index,temperature,magnetic field intensity,and rotating speed have the coupling effects with respect to the nonlinear vibration behavior.
基金Supported by the National Natural Science Foundation of China ( 60603012)the Foundation of Hubei Provincial Department of Education, China (D200610004)
文摘For an odd integer n ≥ 7, this paper presented a class of n-variable rotation symmetric Boolean functions （RSBFs） with optimum algebraic immunity. The nonlinearity of the constructed functions is determined.
文摘Horizontal impedance functions of inclined single piles are measured experimentally for model soil-pile systems with both the effects of local soil nonlinearity and resonant characteristics.Two practical pile inclinations of 5掳 and 10掳 in addition to a vertical pile embedded in cohesionless soil and subjected to lateral harmonic pile head loadings for a wide range of frequencies are considered.Results obtained with low-to-high amplitude of lateral loadings on model soil-pile systems encased in a laminar shear box show that the local nonlinearities have a profound impact on the horizontal impedance functions of piles.Horizontal impedance functions of inclined piles are found to be smaller than the vertical pile and the values decrease as the angle of pile inclination increases.Distinct values of horizontal impedance functions are obtained for the ＇positive＇ and ＇negative＇ cycles of harmonic loadings,leading to asymmetric force-displacement relationships for the inclined piles.Validation of these experimental results is carried out through three-dimensional nonlinear finite element analyses,and the results from the numerical models are in good agreement with the experimental data.Sensitivity analyses conducted on the numerical models suggest that the consideration of local nonlinearity at the vicinity of the soil-pile interface influence the response of the soil-pile systems.
基金Supported by the National Key Basic Research Program of China(No.2013CB834204)
文摘This paper discusses the degree of completeness of cryptographic functions, which is one of the cryptographic criteria should be considered in the design of stream ciphers. We establish the relationships between the degree of completeness and other cryptographic criteria. For resilient Boolean functions, a method to enhance the degree of completeness is proposed, while the nonlinearity and the algebraic degree do not decrease. Moreover, two constructions of resilient functions are provided, which have optimal degree of completeness, high nonlinearity, and high algebraic degree.
基金Key Program of National Natural Science Foundation of China(No.41931076)Laoshan Laboratory(No.LSKJ202205101)+1 种基金National Key R&D Program of China(No.2020YFB0505800)National Natural Science Foundation of China for Young Scholar(No.41904042)。
文摘Any single Positioning,Navigation and Timing(PNT)technology has its vulnerability and limits,even the powerful Global Navigation Satellite System(GNSS)is no exception.To provide continuous and reliable PNT information to users,the theory and technique of comprehensive PNT information system and resilient PNT application system have attracted great attention from Chinese scholars.We try to summarize the progress and development of the synthetic PNT system,including the proposal,the modification and the improvement of the comprehensive PNT,as well as the follow-up resilient PNT.The frame of China’s comprehensive PNT system consisted of comprehensive PNT infrastructure and comprehensive PNT application system is initially described;the achievements on some main PNT technologies are introduced;the conceptual models of resilient PNT are given;besides,existing researches on resilient function models and stochastic models are summarized according to different user scenarios.
