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Near-infrared brain functional characteristics of mild cognitive impairment with sleep disorders
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作者 Heng Liao Sha Liao +5 位作者 Yu-Jiao Gao Xi Wang Li-Hong Guo Su Zheng Wu Yang Yi-Nan Dai 《World Journal of Psychiatry》 SCIE 2025年第1期106-116,共11页
BACKGROUND Mild cognitive impairment(MCI)has a high risk of progression to Alzheimer’s disease.The disease is often accompanied by sleep disorders,and whether sleep disorders have an effect on brain function in patie... BACKGROUND Mild cognitive impairment(MCI)has a high risk of progression to Alzheimer’s disease.The disease is often accompanied by sleep disorders,and whether sleep disorders have an effect on brain function in patients with MCI is unclear.AIM To explore the near-infrared brain function characteristics of MCI with sleep disorders.METHODS A total of 120 patients with MCI(MCI group)and 50 healthy subjects(control group)were selected.All subjects underwent the functional near-infrared spec-troscopy test.Collect baseline data,Mini-Mental State Examination,Montreal Cognitive Assessment scale,fatigue severity scale(FSS)score,sleep parameter,and oxyhemoglobin(Oxy-Hb)concentration and peak time of functional near-infrared spectroscopy test during the task period.The relationship between Oxy-RESULTS Compared with the control group,the FSS score of the MCI group was higher(t=11.310),and the scores of Pittsburgh sleep quality index,sleep time,sleep efficiency,nocturnal sleep disturbance,and daytime dysfunction were higher(Z=-10.518,-10.368,-9.035,-10.661,-10.088).Subjective sleep quality and total sleep time scores were lower(Z=-11.592,-9.924).The sleep efficiency of the MCI group was lower,and the awakening frequency,rem sleep latency period,total sleep time,and oxygen desaturation index were higher(t=5.969,5.829,2.887,3.003,5.937).The Oxy-Hb concentration at T0,T1,and T2 in the MCI group was lower(t=14.940,11.280,5.721),and the peak time was higher(t=18.800,13.350,9.827).In MCI patients,the concentration of Oxy-Hb during T0 was negatively correlated with the scores of Pittsburgh sleep quality index,sleep time,total sleep time,and sleep efficiency(r=-0.611,-0.388,-0.563,-0.356).It was positively correlated with sleep efficiency and total sleep time(r=0.754,0.650),and negatively correlated with oxygen desaturation index(r=-0.561)and FSS score(r=-0.526).All comparisons were P<0.05.CONCLUSION Patients with MCI and sleep disorders have lower near-infrared brain function than normal people,which is related to sleep quality.Clinically,a comprehensive assessment of the near-infrared brain function of patients should be carried out to guide targeted treatment and improve curative effect. 展开更多
关键词 MILD Cognitive impairment Sleep disorders NEAR-INFRARED Brain functional characteristicS
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Dynamic Characteristics of Functionally Graded Timoshenko Beams by Improved Differential Quadrature Method
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作者 Xiaojun Huang Liaojun Zhang +1 位作者 Hanbo Cui Gaoxing Hu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第8期1647-1668,共22页
This study proposes an effective method to enhance the accuracy of the Differential Quadrature Method(DQM)for calculating the dynamic characteristics of functionally graded beams by improving the form of discrete node... This study proposes an effective method to enhance the accuracy of the Differential Quadrature Method(DQM)for calculating the dynamic characteristics of functionally graded beams by improving the form of discrete node distribution.Firstly,based on the first-order shear deformation theory,the governing equation of free vibration of a functionally graded beam is transformed into the eigenvalue problem of ordinary differential equations with respect to beam axial displacement,transverse displacement,and cross-sectional rotation angle by considering the effects of shear deformation and rotational inertia of the beam cross-section.Then,ignoring the shear deformation of the beam section and only considering the effect of the rotational inertia of the section,the governing equation of the beam is transformed into the eigenvalue problem of ordinary differential equations with respect to beam transverse displacement.Based on the differential quadrature method theory,the eigenvalue problem of ordinary differential equations is transformed into the eigenvalue problem of standard generalized algebraic equations.Finally,the first several natural frequencies of the beam can be calculated.The feasibility and accuracy of the improved DQM are verified using the finite element method(FEM)and combined with the results of relevant literature. 展开更多
关键词 Timoshenko beams functionally graded materials dynamic characteristics natural frequency improved differential quadrature method
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Effects of Functional Fish Organizations on the Fractal Characteristics of the Microstructure of Feces
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作者 QIAO Lina WANG Hongshuai LIU Yao 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第6期1655-1665,共11页
Fish feces affect the structure and function of aquatic ecosystems,and they are affected by the functional fish organizations.In this research,Ctenopharyngodon idellus,Hypophthalmichthys molitrix,and Cyprinus carpio w... Fish feces affect the structure and function of aquatic ecosystems,and they are affected by the functional fish organizations.In this research,Ctenopharyngodon idellus,Hypophthalmichthys molitrix,and Cyprinus carpio were selected to study the effects of different functional fish organizations on the fractal characteristics of fecal micro-structure by scanning electron microscopes(SEM),particles(pores)and cracks analysis system(PCAS).The results showed that fish feces pores mainly consisted of medium pores(cumulative pore number,97%)classified by the International Union of Pure and Applied Chemistry(IUPAC).The grain area fractal dimension D_(1) and the pore-number and pore-size fractal dimension D_(2) were 1.94-1.96 and 2.07-2.19,respectively.The distribution of fish feces pores was very close to the Sierpinski carpet structure,which is the basic fractal construction methods widely used to describe the fractal of pore surface distribution.D_(1)(1.96)and D_(2)(2.19)of Hypophthalmichthys molitrix were the maximum values of the three functional organizations.Combining with the habit of fish,it is inferred that the feces of H.molitrix,the finer the feed and the faster the swimming of fish,the higher the content of feces clay,the larger the fractal dimension of feces,the easier it is to decompose feces,and the high the content of nutrients and organic matter to release into the water.It is demined that fish functional organizations affected the fractal characteristics and the stability of fish feces in water.This study is helpful for further research on water quality prediction and the impact of functional fish organizations on the structure and function of the ecosystem. 展开更多
关键词 functional fish organizations feces microstructure fractal characteristic scanning electron microscopy(SEM) particles(pores)and cracks analysis system(PCAS)
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Construction of Orthogonal Vector-valued Wavelets and Characteristics of Vector-valued Wavelet Packets 被引量:1
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作者 CHEN Qing-jiang LIU Hong-yun 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第3期360-367,共8页
The notion of vector-valued multiresolution analysis is introduced and the concept of orthogonal vector-valued wavelets with 3-scale is proposed. A necessary and sufficient condition on the existence of orthogonal vec... The notion of vector-valued multiresolution analysis is introduced and the concept of orthogonal vector-valued wavelets with 3-scale is proposed. A necessary and sufficient condition on the existence of orthogonal vector-valued wavelets is given by means of paraunitary vector filter bank theory. An algorithm for constructing a class of compactly supported orthogonal vector-valued wavelets is presented. Their characteristics is discussed by virtue of operator theory, time-frequency method. Moreover, it is shown how to design various orthonormal bases of space L^2(R, C^n) from these wavelet packets. 展开更多
关键词 ORTHOGONAL Hermitian matrix vector-valued multiresolution analysis vector-valued scaling functions vector-valued wavelets vector-valued wavelet packets
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Characteristics and Functions of Cooperative Economic Organizations for Water-saving Irrigation in Agricultural Development in Arid Areas 被引量:4
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作者 吴开波 朱美玲 +1 位作者 董新光 李金 《Agricultural Science & Technology》 CAS 2011年第12期1979-1982,共4页
Agricultural cooperative economic organization for water-saving irrigation in arid areas is a new form of economic organization in production,operation and management during the application process of water-saving irr... Agricultural cooperative economic organization for water-saving irrigation in arid areas is a new form of economic organization in production,operation and management during the application process of water-saving irrigation technologies.Currently,there are few researches on this cooperative economic organization.In this study,connotations of cooperative economic organizations for water-saving irrigation are specifically defined,and the characteristics and functions of this cooperative economic organization are analyzed.Based on that,several suggestions are proposed on the continuous development of cooperative economic organizations for water-saving irrigation. 展开更多
关键词 Cooperative economic organizations Water-saving irrigation characteristicS functionS
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Metabolic Characteristics and Functional Diversity of Carbon Source in Microflora of Ponds with Recirculating Aquaculture System 被引量:2
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作者 李谷 宋景华 +3 位作者 李晓莉 张世羊 陶玲 张春雪 《Agricultural Science & Technology》 CAS 2014年第2期278-282,299,共6页
With Biolog Eco microplate, metabolic characteristics and functional diver-sity of carbon source in microflora of ponds were researched based on recitculating ponds and control ponds in order to explore effects of eco... With Biolog Eco microplate, metabolic characteristics and functional diver-sity of carbon source in microflora of ponds were researched based on recitculating ponds and control ponds in order to explore effects of eco-adjustments on microflo-ra in ponds. The results indicate that total number of bacterium, microbial metabolism activity, and diversity index in P7, P8, P1 and P2 kept higher, fol owed by P3, P4, P5 and P6. The utilization rate of microbes on sugars achieved the highest (31.0%-48.7%), fol owed by carboxylic acid (13.4%-18.0%), amino acid (10.1%-20.5%), polymers (9.4%-17.0%), biopolymer (5.7%-9.7%) and phenol (4.95%-7.50%). Principal component analysis divided microflora in different ponds, suggesting that microbial community has varied carbon source characteristics and nitrogen-containing compound and biopolymer metabolisms are most affected. 展开更多
关键词 Aquaculture pond MICROBE -Metabolic characteristics of carbon source functional diversity
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Analysis on the Functions and Properties of the Preliminarily Determined Characteristics Listed in DUS Test Guideline of Tagetes L.
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作者 刘艳芳 张建华 +5 位作者 杨晓洪 张惠 陈海荣 徐云 管俊娇 王江民 《Agricultural Science & Technology》 CAS 2012年第8期1789-1792,共4页
[Objective] This study aimed to investigate the functions and properties of the preliminarily determined characteristics listed in DUS test guideline of Tagetes L., and explore the representativeness and comprehensive... [Objective] This study aimed to investigate the functions and properties of the preliminarily determined characteristics listed in DUS test guideline of Tagetes L., and explore the representativeness and comprehensiveness of this group of characteristics in DUS test. [Method] Based on the functions and properties of the characteristics, the described plant part (s), observation stage, expression pattern and observation method of each characteristic were analyzed to illustrate the representativeness and comprehensiveness of the combination of this group of characteristics in above functions and properties. [Result] As for described plant part(s), there are 5 characteristics describing plant as a whole, 3 characteristics describing stem, 6 characteristics describing leaf, 23 characteristics describing flower and 1 characteristic describing physiological feature. As for observation stage, there are 1 characteristic needing to be observed in the stage of seedling, 1 characteristic in the stage of beginning of flowering and other 36 characteristics in the stage of fully flowering. As for the expression pattern, there are 10 qualitative characteristics, 9 pseudo-qualitative characteristics and 19 quantitative characteristics. As for the observation method, there are 30 characteristics using VG as the observation method, and 8 characteristics using MS. [Conclusion] In view of the variation and morphological properties of marigold, this group of characteristics are representative and comprehensive, and ensure the accuracy and easiness of DUS test of Tagetes L., thereby achieving the reasonable combination of characteristics in described plant parts, observation stages, expression patterns and observation methods. 展开更多
关键词 DUS test guideline of Tagetes L. characteristic function PROPERTY
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Cultural Characteristics and Communicative Functions of English Euphemism
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作者 谢彩云 《科技信息》 2011年第34期200-200,202,共2页
Euphemism is a linguistic concept and meanwhile a cultural phenomenon.It truly reflects the life and values of English people through history,thus is closely linked with the culture of English-speaking countries.Moreo... Euphemism is a linguistic concept and meanwhile a cultural phenomenon.It truly reflects the life and values of English people through history,thus is closely linked with the culture of English-speaking countries.Moreover,euphemism has significant social functions.It has been causing wide interest in people.Many linguistic researchers and scholars have done much research on it.Based on their achievements the author will have an exploration of the cultural characteristics and social functions of English euphemism. 展开更多
关键词 英语教学 教学方法 阅读教学 英语翻译
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LAD PARAMETER ESTIMATION of SaS BASED on SAMPLE CHARACTERISTIC FUNCTION
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作者 陈高波 《科技信息》 2010年第25期I0028-I0028,I0027,共2页
Parameter estimation to alpha stable distribution is difficult for without a explicit probability density function. On the base of sample characteristic function,an iterative LAD parameter estimation algorithm for SaS... Parameter estimation to alpha stable distribution is difficult for without a explicit probability density function. On the base of sample characteristic function,an iterative LAD parameter estimation algorithm for SaS is discussed. The example illustrates that the algorithm is feasible and efficient. 展开更多
关键词 概率 密度函数 计算方法 迭代参数
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Analysis of Ocean Wave Characteristic Distributions Modeled by Two Different Transformed Functions 被引量:2
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作者 Duanfeng Han Ting Cui +3 位作者 Yingfei Zan Lihao Yuan Song Ding Zhigang Li 《Journal of Marine Science and Application》 CSCD 2019年第3期247-259,共13页
The probability distributions of wave characteristics from three groups of sampled ocean data with different significant wave heights have been analyzed using two transformation functions estimated by non-parametric a... The probability distributions of wave characteristics from three groups of sampled ocean data with different significant wave heights have been analyzed using two transformation functions estimated by non-parametric and parametric methods. The marginal wave characteristic distribution and the joint density of wave properties have been calculated using the two transformations, with the results and accuracy of both transformations presented here. The two transformations deviate slightly between each other for the calculation of the crest and trough height marginal wave distributions, as well as the joint densities of wave amplitude with other wave properties. The transformation methods for the calculation of the wave crest and trough height distributions are shown to provide good agreement with real ocean data. Our work will help in the determination of the most appropriate transformation procedure for the prediction of extreme values. 展开更多
关键词 Wave characteristic DISTRIBUTIONS Transformed GAUSSIAN process Transformed function PARAMETRIC METHOD NON-PARAMETRIC METHOD Crossing-density function
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Synthetically quantitative evaluation function of characteristic parameters on CO_2 arc welding process 被引量:4
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作者 俞建荣 蒋力培 +2 位作者 史耀武 孙振国 王军波 《China Welding》 EI CAS 2001年第1期19-26,共8页
The statistical probability and their variation regularity of the measurable characteristic parameters in the CO 2 arc welding droplet short circuiting transfer process have been studied. The statistical analysis sh... The statistical probability and their variation regularity of the measurable characteristic parameters in the CO 2 arc welding droplet short circuiting transfer process have been studied. The statistical analysis shows that the sensitivity of each characteristic parameter with regard to the variation of the short circuiting transfer process is different. The sensitivity of 4 kinds among these characteristic parameters is more intense than that of the short circuiting transfer frequency. In order to take account of the synthetic influence of these characteristic parameters, by means of the characteristic parameters synthetic value, a quantitative evaluation function is built up to describe and evaluate the short circuiting transfer process of CO 2 arc welding in real time. The testing shows that the evaluation function can give a suitable synthetic valuation for the short circuiting transfer process with a variety of welding variables. 展开更多
关键词 CO 2 arc welding process characteristic parameters quantitative evaluation function
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The Characteristic Function Method and Its Application to (1 + 1)-Dimensional Dispersive Long Wave Equation 被引量:2
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作者 Medhat M. Helal Mohammad L. Mekky Emad A. Mohamed 《Applied Mathematics》 2012年第1期12-18,共7页
In this paper, the characteristic function method is applied to seek traveling wave solutions of nonlinear partial differential equations in a unified way. We consider the Wu-Zhang equation (which describes (1 + 1)-di... In this paper, the characteristic function method is applied to seek traveling wave solutions of nonlinear partial differential equations in a unified way. We consider the Wu-Zhang equation (which describes (1 + 1)-dimensional disper-sive long wave). The equations governing the wave propagation consist of a pair of non linear partial differential equations. The characteristic function method reduces the system of nonlinear partial differential equations to a system of nonlinear ordinary differential equations which is solved via the shooting method, coupled with Rungekutta scheme. The results include kink-profile solitary wave solutions, periodic wave solutions and rational solutions. As an illustrative example, the properties of some soliton solutions for Wu-Zhang equation are shown by some figures. 展开更多
关键词 characteristic function Method Wu-Zhang EQUATION
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Relations Between Characteristic Function,Positive P-Representation and Coherent Thermal State 被引量:1
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作者 FAN Hong-Yi XU Xing-Lei Department of Material Science and Engineering,University of Science and Technology of China,Hefei 230026,China2 Department of Physics,Shanghai Jiao Tong University,Shanghai 200030,China3 Department of Physics,Heze University,Heze 274015,China 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第7期67-70,共4页
We employ the coherent thermal states(a kind of entangled states)in thermal field dynamics to establisha complete entangled state formalism expressing pseudo-classical representations of density operator for light fie... We employ the coherent thermal states(a kind of entangled states)in thermal field dynamics to establisha complete entangled state formalism expressing pseudo-classical representations of density operator for light field.Especially,the relationship between the coherent thermal state and the characteristic function and the positive Prepresentation in quantum optics theory are obtained. 展开更多
关键词 coherent thermal state characteristic function positive P-representation
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Characteristic Functional Structure of Infinitesimal Symmetry Transformations for Nonholonomic System 被引量:1
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作者 张宏彬 陈立群 《Journal of Shanghai University(English Edition)》 CAS 2005年第2期134-138,共5页
It was proved that velocity-dependent infinitesima l symmetry transformations of nonholonomic systems have a characteristic functio nal structure, which could be formulated by means of an auxiliary symmetry tra nsform... It was proved that velocity-dependent infinitesima l symmetry transformations of nonholonomic systems have a characteristic functio nal structure, which could be formulated by means of an auxiliary symmetry tra nsformation function and is manifestly dependent upon constants of motion of th e system. An example was given to illustrate the applicability of the results. 展开更多
关键词 analytical mechanics nonholonomic system velocity-dependent infinitesimal symmetry transformation characteristic functional structure constant of motion.
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Characteristic and Functions of Architectural Cultures in Traditional Villages of Ningbo 被引量:1
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作者 HUANG Shuna 《Journal of Landscape Research》 2015年第5期57-58,60,共3页
Further promotion of urbanization has resulted in the broken integrity of architectural environment and cultural system of traditional villages, and some traditional villages with historical architectural styles have ... Further promotion of urbanization has resulted in the broken integrity of architectural environment and cultural system of traditional villages, and some traditional villages with historical architectural styles have been on the verge of extinction. Against the background of building "beautiful Zhejiang and good life", Ningbo City has to optimize the livable environment continuously, integrate natural, humanistic, green, characteristic and comfortable elements into the beautiful countryside construction, thus it is urgent to explore the cultural characteristics and functions of architectural environment in traditional villages. Cultural characteristics and functions of architectural environment in traditional villages of Ningbo should be more systematic, legalized, and scientific. This paper reviewed concepts and cultural connotations of traditional villages, and integrated cultural characteristics and functions of regional architectural environment in traditional villages of Ningbo, and provided references for theoretic researches on the formation of characteristic regional architectural cultures in traditional villages of Ningbo. 展开更多
关键词 Traditional village Regionality Architectural cultural characteristics Architectural cultural functions
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Natural dynamic characteristics of a circular cylindrical Timoshenko tube made of three-directional functionally graded material 被引量:3
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作者 Ye TANG Jiye XU Tianzhi YANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2022年第4期479-496,共18页
The natural dynamic characteristics of a circular cylindrical tube made of three-directional(3 D)functional graded material(FGM)based on the Timoshenko beam theory are investigated.Hamilton’s principle is utilized to... The natural dynamic characteristics of a circular cylindrical tube made of three-directional(3 D)functional graded material(FGM)based on the Timoshenko beam theory are investigated.Hamilton’s principle is utilized to derive the novel motion equations of the tube,considering the interactions among the longitudinal,transverse,and rotation deformations.By dint of the differential quadrature method(DQM),the governing equations are discretized to conduct the analysis of natural dynamic characteristics.The Ritz method,in conjunction with the finite element method(FEM),is introduced to verify the present results.It is found that the asymmetric modes in the tube are controlled by the 3 D FGM,which exhibit more complicated shapes compared with the unidirectional(1 D)and bi-directional(2 D)FGM cases.Numerical examples illustrate the effects of the axial,radial,and circumferential FGM indexes as well as the supported edges on the natural dynamic characteristics in detail.It is notable that the obtained results are beneficial for accurate design of smart structures composed from multi-directional FGM. 展开更多
关键词 circular cylindrical tube three-directional(3D)functionally graded material(FGM) asymmetric mode natural dynamic characteristic differential quadrature method(DQM)
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Global Avalanche Characteristics of Boolean Functions by Concatenation
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作者 Zepeng Zhuo Jinfeng Chong +1 位作者 Ruirui Yu Mingsheng Ren 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2016年第3期91-96,共6页
In order to measure the correlation propeties of two Boolean functions,the global avalanche characteristics of Boolean functions constructed by concatenation are discussed,i.e.,f_1‖f_2and f_1‖f_2‖f_3‖f_4.Firstly,f... In order to measure the correlation propeties of two Boolean functions,the global avalanche characteristics of Boolean functions constructed by concatenation are discussed,i.e.,f_1‖f_2and f_1‖f_2‖f_3‖f_4.Firstly,for the function f = f_1‖f_2,the cross-correlation function of f_1,f_2 in the special condition are studied.In this case,f,f_1,f_2 must be in desired form.By computing their sum-of-squares indicators,the crosscorrelation function between f_1,f_2 is obtained.Secondly,for the function g = f_1‖f_2‖f_3‖f_4,by analyzing the relation among their auto-correlation functions,their sum-of-squares indicators are investigated.Based on them,the sum-of-squares indicators of functions obtained by Canteaut et al.are investigated.The results show that the correlation property of g is good when the correlation properties of Boolean functions f_1,f_2,f_3,f_4 are good. 展开更多
关键词 BOOLEAN function CROSS-CORRELATION function GLOBAL AVALANCHE characteristics sum-of-squaresindicator
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CRITERION AND APPRAISABLE FUNCTION OF SIZE CHARACTERISTICS
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作者 Xie, Hengxing Yi, Guohong Li, Songren 《中国有色金属学会会刊:英文版》 EI CSCD 1997年第1期9-13,共5页
CRITERIONANDAPPRAISABLEFUNCTIONOFSIZECHARACTERISTICS①XieHengxing,YiGuohong,LiSongrenDepartmentofMineralEngin... CRITERIONANDAPPRAISABLEFUNCTIONOFSIZECHARACTERISTICS①XieHengxing,YiGuohong,LiSongrenDepartmentofMineralEngineering,CentralSou... 展开更多
关键词 SIZE SIZE characteristicS CRITERION appraisable function
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Multilevel Characteristic Basis Function Method with ACA for Accelerated Solution of Electrically Large Scattering Problems
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作者 Li Chenlu Sun Yufa +1 位作者 Wang Zhonggen Wang Guohua 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2018年第3期449-454,共6页
The multilevel characteristic basis function method(MLCBFM)with the adaptive cross approximation(ACA)algorithm for accelerated solution of electrically large scattering problems is studied in this paper.In the convent... The multilevel characteristic basis function method(MLCBFM)with the adaptive cross approximation(ACA)algorithm for accelerated solution of electrically large scattering problems is studied in this paper.In the conventional MLCBFM based on Foldy-Lax multiple scattering equations,the improvement is only made in the generation of characteristic basis functions(CBFs).However,it does not provide a change in impedance matrix filling and reducing matrix calculation procedure,which is time-consuming.In reality,all the impedance and reduced matrix of each level of the MLCBFM have low-rank property and can be calculated efficiently.Therefore,ACA is used for the efficient generation of two-level CBFs and the fast calculation of reduced matrix in this study.Numerical results are given to demonstrate the accuracy and efficiency of the method. 展开更多
关键词 multilevel characteristic basis function method(MLCBFM) adaptive cross approximation(ACA) characteristic basis functions(CBFs) electromagnetic scattering
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Genetic-algorithm-based balanced distribution of functional characteristics for machines
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作者 王国新 杜景军 阎艳 《Journal of Beijing Institute of Technology》 EI CAS 2015年第1期49-57,共9页
In order to make reconfigurable manufacturing system (RMS) adapt to the fluctuations of production demand with the minimum number of reconflgurations in its full life cycle, we presented a method to design RMS based... In order to make reconfigurable manufacturing system (RMS) adapt to the fluctuations of production demand with the minimum number of reconflgurations in its full life cycle, we presented a method to design RMS based on the balanced distribution of functional characteristics for ma- chines. With this method, functional characteristics were classified based on machining functions of cutting-tools and machining accuracy of machines. Then the optimization objective was set as the to- tal shortest mobile distance that all the workpieces are moved from one machine to another, and an improved genetic algorithm (GA) was proposed to optimize the configuration. The elitist strategy was used to enhance the global optimization ability of GA, and excellent gene pool was designed to maintain the diversity of population. Software Matlab was used to realize the algorithm, and a case study of simulation was used to evaluate the method. 展开更多
关键词 reconfigurable manufacturing systems balanced distribution functional characteristics genetic algorithm
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