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网络度-度相关性对Parrondo博弈的影响分析
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作者 杭小荣 叶晔 +1 位作者 王璐 谢能刚 《信息与电脑》 2019年第10期24-27,共4页
笔者采用基于复杂网络的群体Parrondo博弈模型,模型由A、B两个博弈组成。其中,A博弈设计为马太方式,B博弈设计为依赖资本形式。通过观察Parrondo悖论成立的参数空间从同配网络至异配网络的渐进变化情况,分析度-度相关性对Parrondo悖论... 笔者采用基于复杂网络的群体Parrondo博弈模型,模型由A、B两个博弈组成。其中,A博弈设计为马太方式,B博弈设计为依赖资本形式。通过观察Parrondo悖论成立的参数空间从同配网络至异配网络的渐进变化情况,分析度-度相关性对Parrondo悖论效应的影响,并针对一组参数,详细分析异配网络下系统发生悖论的微观原因,揭示了B博弈的不对称结构、A博弈的'搅动'作用以及网络拓扑结构的共同作用机制。 展开更多
关键词 Parrondo悖论 度-度相关 复杂网络
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HIV传播度‐度相关分层无标度网络生成算法 被引量:1
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作者 何晓力 王海瑞 毕贵红 《系统仿真学报》 CAS CSCD 北大核心 2014年第2期279-288,293,共11页
社会网络结构对HIV传播有重要影响。提出了一种网络节点度分布具有无标度特性和度-度相关的动态HIV同性传播社会网络模型。根据网络中节点的度即伙伴关系数量将节点分成三层,对应三类不同高危行为人群,利用配置模型生成关系网络时,层内... 社会网络结构对HIV传播有重要影响。提出了一种网络节点度分布具有无标度特性和度-度相关的动态HIV同性传播社会网络模型。根据网络中节点的度即伙伴关系数量将节点分成三层,对应三类不同高危行为人群,利用配置模型生成关系网络时,层内连接有较大同类匹配连接概率和层间有较小的异类匹配连接概率,并考虑了伙伴间的固定和偶然连接关系以及连接关系断开和重连的动态演化特性。生成网络模型,并对复杂网络属性进行度量,验证了动态分层无标度网络既有指数可调的无标度网络特性,又有较高的聚类系数、动态和同类匹配特性,更符合社会网络的特性,为研究HIV传播和其他动态社会网络提供基础。 展开更多
关键词 分层无标网络 分布 度-度相关 聚类系数 动态网络
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Evaluation of Phonon-level Density of UO2 by Molecular Dynamics Simulation 被引量:1
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作者 张慧芬 李赣 +1 位作者 田晓峰 高涛 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第4期399-404,I0003,共7页
Molecular dynamics calculation of UO2 in a wide temperature range are presented and dis- cussed. The calculated lattice parameters, mean square displacements, and dynamic prop- erty of phonon-level density of the velo... Molecular dynamics calculation of UO2 in a wide temperature range are presented and dis- cussed. The calculated lattice parameters, mean square displacements, and dynamic prop- erty of phonon-level density of the velocity auto-correlation functions for UO2 are provided. The Morelon potential and the Basak potential are employed. It confirms that the cal- culated lattice parameters using the Basak potential are in nearly perfect agreement with the reported values. The models successfully predict mean square displacement and Bredig transition. Furthermore, the phonon-level density of uranium dioxide are discussed. The intensity of phonon-level density increases with temperature, and the properties of UO2 are characterized by large thermal vibrations rather than extensive disorder. 展开更多
关键词 Molecular dynamics Phonon-level density Velocity auto-correlation function Uranium dioxide
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Lipoxygenase Activity and Its Relationship with Traits of Whole-mill Color in Wheat 被引量:1
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作者 包晓婷 颛孙湘溪 +3 位作者 郑文寅 张文明 郭文善 姚大年 《Agricultural Science & Technology》 CAS 2016年第10期2242-2246,2255,共6页
130 wheat varieties are selected as materials to test the LOX activity, whiteness, yellowness, carotenoids content and RVA parameters, which are to be analyzed by variance analysis, correlation analysis, cluster analy... 130 wheat varieties are selected as materials to test the LOX activity, whiteness, yellowness, carotenoids content and RVA parameters, which are to be analyzed by variance analysis, correlation analysis, cluster analysis and classified according to the origins. The result shows there are highly significant variations in LOX activity from varieties; LOX activity is positively correlated with whiteness, and significantly and negatively correlated with yellowness. Cluster analysis applying longest distance method based on LOX activity clusters all the varieties or lines into three major groups. There are great differences between the averages of LOX activity from varieties. LOX activities are discussed in the application of nutritional quality improvement in wheat. 展开更多
关键词 WHEAT LOX WHITENESS Yellowness Carotenoids Correlation analysis Cluster analysis
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Phase Structure in a Quark Mass Density-and-Temperature-Dependent Model 被引量:1
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作者 WEN Xin-Jian PENG Guang-Xiong SHEN Peng-Nian 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第1期78-84,共7页
The phase diagram of bulk quark matter in equilibrium with a finite hadronic gas is studied. Different from previous investigations, we treat the quark phase with the quark mass density-and-temperature-dependent model... The phase diagram of bulk quark matter in equilibrium with a finite hadronic gas is studied. Different from previous investigations, we treat the quark phase with the quark mass density-and-temperature-dependent model to take the strong quark interaction into account, while the hadron phase is treated by hard core repulsion factor. It is found that the phase diagram in this model is, in several aspects, different from those in the conventional MIT bag model, especially at high temperature. The new phase diagram also has strong effects on the mass-radius relation of compact hybrid stars. 展开更多
关键词 phase diagram quark matter hadron matter
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STUDY ON THE RELATIONSHIP BETWEEN BRIGHTNESS TEMPERATURE FROM GMS-5 INFRARED CLOUD IMAGERY AND SURFACE RAIN RATES DURING THE RAINING SEASONS OF FUJIAN PROVINCE 被引量:2
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作者 林长城 张长安 +3 位作者 林忠敏 林祥明 谢怡芳 郑淑贞 《Journal of Tropical Meteorology》 SCIE 2003年第1期74-79,共6页
The GMS-5 infrared cloud imagery for two yearly first raining seasons in 1998 and 1999 are used to study the relationship between brightness temperature and surface rain rates. The result shows that it is likely to ha... The GMS-5 infrared cloud imagery for two yearly first raining seasons in 1998 and 1999 are used to study the relationship between brightness temperature and surface rain rates. The result shows that it is likely to have large probability of heavy precipitation with the decrease of brightness temperature and the gradual increase of rainfall intensity; for areas of low temperature, the brightness temperature is better determined for atmosphere above rain gauge stations with multiple points sampling than with single point one; for the yearly first raining season, the threshold brightness temperature is set at 4.6℃ for indication of heavy precipitation in the Fujian area. 展开更多
关键词 yearly first raining seasons GMS-5 cloud top temperature rainfall intensity
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Sensitivity of the Number of Snow Cover Days to Surface Air Temperature over the Qinghai-Tibetan Plateau 被引量:1
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作者 Lijuan Ma Dahe Qin +2 位作者 Lingen Bian Cunde Xiao Yong Luo 《Advances in Climate Change Research》 SCIE 2010年第2期76-83,共8页
Based on the number of snow cover days (NSCDs) and homogenized surface air temperature data for the period 1951-2004, this study performs the quantitative analysis on the sensitivity of NSCDs to surface air temperat... Based on the number of snow cover days (NSCDs) and homogenized surface air temperature data for the period 1951-2004, this study performs the quantitative analysis on the sensitivity of NSCDs to surface air temperature over the Qinghai-Tibetan Plateau (QTP). Results show that both the extreme sensitivity and sensitivity under current climate are higher in the edge than in the central area of the QTP. There exists a strong negative correlation between station's elevation and critical temperature, at which the sensitivity reaches extremum. The negative correlation between the elevation and the extreme sensitivity is not as strong as the former one. Currently, the climatological temperatures in quite a few stations do not reach the critical stage. The sensitivity at these stations will become greater under the current background of climate warming, which means NSCDs will be more sensitive to surface air temperature. 展开更多
关键词 snow cover sensitivity Qinghai-Tibetan Plateau surface air temperature
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基于复杂网络的中国南方航空网络研究
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作者 李振全 史晓红 +2 位作者 张越 任轩禾 徐颖 《舰船电子工程》 2024年第3期110-115,共6页
随着经济的快速发展和全球化进程的加快,国内航空运输网络的不断扩大,航空业的迅速发展使得对航空网络的研究具有较大的意义。文中以中国南方航空公司2021-2022年冬春航班计划为基础,运用复杂网络的基础理论分析中国南方航空航线网络的... 随着经济的快速发展和全球化进程的加快,国内航空运输网络的不断扩大,航空业的迅速发展使得对航空网络的研究具有较大的意义。文中以中国南方航空公司2021-2022年冬春航班计划为基础,运用复杂网络的基础理论分析中国南方航空航线网络的特性,将南方航空网络的特性与中国航空网络的特性进行对比。再运用度中心性、介数中心性、接近度中心性三种中心性分析指标对南方航空网络进行节点重要性排序,分析在不同中心性指标因素下节点的重要性。最后对研究成果进行分析和展望。 展开更多
关键词 航空运输 复杂网络 南方航空 幂律分布 度-度相关 中心性
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NOVEL GENERALIZED GREY INCIDENCE MODEL BASED ON INTERVAL GREY NUMBERS 被引量:4
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作者 谢乃明 郑静 辛江慧 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第2期118-124,共7页
To extend the traditional generalized grey incidence model, a novel grey incidence model based on inter- val grey numbers is constructed. Considering the numerical information of indexes cannot be accurately obtained ... To extend the traditional generalized grey incidence model, a novel grey incidence model based on inter- val grey numbers is constructed. Considering the numerical information of indexes cannot be accurately obtained and can be defined as interval grey numbers, the interval grey numbers are defined as standard interval grey num- bers which are split in white part and grey part. The absolute degree of incidence and relative degree of incidence based on the interval grey numbers are constructed and their arithmetic are given. Finally, an example about commercial aircraft index selection illuminates the effectiveness of the model. The results show that the model can sort indexes better and can extend the grey incidence models significantly. 展开更多
关键词 grey system grey incidence analysis standard interval grey number absolute degree of incidencerelative degree of incidence
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层间耦合关联对多层网络交通传输的影响
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作者 胡亚琴 唐明 《华东师范大学学报(自然科学版)》 CAS CSCD 北大核心 2021年第3期105-113,共9页
多层网络能更好地反映真实世界中许多系统的结构和特征,近年来已逐渐成为人们的研究热点.基于层间节点的度-度相关性,提出了一种层间中间度耦合方式,目的是在较低的层间耦合成本下提高网络传输容量.在最短路径和有效路由这两种经典的路... 多层网络能更好地反映真实世界中许多系统的结构和特征,近年来已逐渐成为人们的研究热点.基于层间节点的度-度相关性,提出了一种层间中间度耦合方式,目的是在较低的层间耦合成本下提高网络传输容量.在最短路径和有效路由这两种经典的路由策略下,分别验证了中间度耦合方式的有效性.与同配耦合、异配耦合和随机耦合这3种耦合方式相比,中间度耦合方式可以使网络中流量的分布更加均匀、网络传输容量的提升更大,并可有效降低数据包在网络中的平均传输时间.数据包采用有效路由策略传输时,在较低的耦合概率下,中间度耦合方式更能明显地提高网络的传输容量;同时,仿真发现均匀的网络拓扑结构具备更高的承载能力. 展开更多
关键词 多层网络 度-度相关 耦合方式 网络拥塞
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Study on the scales of heterogeneous geologic bodies in random media 被引量:2
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作者 李灿苹 刘学伟 《Applied Geophysics》 SCIE CSCD 2011年第4期363-369,373,共8页
In order to study the scale characteristics of heterogeneities in complex media, a random medium is constructed using a statistical method and by changing model parameters (autocorrelation lengths a and b), the scal... In order to study the scale characteristics of heterogeneities in complex media, a random medium is constructed using a statistical method and by changing model parameters (autocorrelation lengths a and b), the scales of heterogeneous geologic bodies in the horizontal and the vertical Cartesian directions may be varied in the medium. The autocorrelation lengths a and b represent the mean scale of heterogeneous geologic bodies in the horizontal and vertical Cartesian directions in the randQm medium, respectively. Based on this model, the relationship between model autocorrelation lengths and heterogeneous geologic body scales is studied by horizontal velocity variation and standard deviation. The horizontal velocity variation research shows that velocities are in random perturbation. The heterogeneous geologic body scale increases with increasing autocorrelation length. The recursion equation for the relationship between autocorrelation lengths and heterogeneous geologic body scales is determined from the velocity standard deviation research and the actual heterogeneous geologic body scale magnitude can be estimated by the equation. 展开更多
关键词 random medium autocorrelation length velocity standard deviation heterogeneous geologic body scale
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Probabilistic durability assessment approach of deteriorating RC bridges 被引量:5
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作者 朱劲松 高嫦娥 《Journal of Southeast University(English Edition)》 EI CAS 2011年第1期70-76,共7页
A stochastic finite element computational methodology for probabilistic durability assessment of deteriorating reinforced concrete(RC) bridges by considering the time-and space-dependent variabilities is presented.F... A stochastic finite element computational methodology for probabilistic durability assessment of deteriorating reinforced concrete(RC) bridges by considering the time-and space-dependent variabilities is presented.First,finite element analysis with a smeared cracking approach is implemented.The time-dependent bond-slip relationship between steel and concrete,and the stress-strain relationship of corroded steel bars are considered.Secondly,a stochastic finite element-based computational framework for reliability assessment of deteriorating RC bridges is proposed.The spatial and temporal variability of several parameters affecting the reliability of RC bridges is considered.Based on the data reported by several researchers and from field investigations,the Monte Carlo simulation is used to account for the uncertainties in various parameters,including local and general corrosion in rebars,concrete cover depth,surface chloride concentration,chloride diffusion coefficient,and corrosion rate.Finally,the proposed probabilistic durability assessment approach and framework are applied to evaluate the time-dependent reliability of a girder of a RC bridge located on the Tianjin Binhai New Area in China. 展开更多
关键词 stochastic finite element method space-dependent reliability time-dependent reliability durability assessment concrete carbonation corrosion of rebars
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Outlet Temperature Correlation and Prediction of Transfer Line Exchanger in an Industrial Steam Ethylene Cracking Process 被引量:3
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作者 金阳坤 李进龙 +2 位作者 杜文莉 王振雷 钱锋 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第4期388-394,共7页
Predicting the best shutdown time of a steam ethylene cracking furnace in industrial practice remains a challenge due to the complex coking process. As well known, the shutdown time of a furnace is mainly determined b... Predicting the best shutdown time of a steam ethylene cracking furnace in industrial practice remains a challenge due to the complex coking process. As well known, the shutdown time of a furnace is mainly determined by coking condition of the transfer line exchangers (TLE) when naphtha or other heavy hydrocarbon feedstocks are cracked. In practice, it is difficult to measure the coke thickness in TLE through experimental method in the complex industrial situation. However, the outlet temperature of TLE (TLEOT) can indirectly characterize the coking situation in TLE since the coke accumulation in TLE has great influence on TLEOT. Thus, the TLEOT could be a critical factor in deciding when to shut down the furnace to decoke. To predict the TLEOT, a paramewic model was proposed in this work, based on theoretical analysis, mathematic reduction, and parameters estimation. The feasibility of the proposed model was further checked through industrial data and good agreements between model prediction and industrial data with maximum deviation 2% were observed. 展开更多
关键词 transfer line exchanger outlet temperature parametric model steam ethylene cracking
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RELATIONSHIP BETWEEN DIPOLE OSCILLATION OF SSTA OF INDIAN OCEAN REGION AND PRECIPITATION AND TEMPERATURE IN CHINA 被引量:1
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作者 肖子牛 晏红明 李崇银 《Journal of Tropical Meteorology》 SCIE 2002年第2期121-131,共11页
The work is a general survey using SSTA data of the Indian Ocean and of precipitation at 160Chinese weather stations over 1951~1997 (47 years). It reveals that the dipole oscillation of SST, especially the dipole ind... The work is a general survey using SSTA data of the Indian Ocean and of precipitation at 160Chinese weather stations over 1951~1997 (47 years). It reveals that the dipole oscillation of SST, especially the dipole index of March~May, in the eastern and western parts of the ocean correlates well with the precipitation during the June~August raining season in China. As shown in analysis of 500-hPa Northern Hemisphere geopotential height height by NCEP for 1958~1995, the Indian Ocean dipole index (IODI) is closely related with geopotential height anomalies in the middle- and higher- latitudes in the Eurasian region. As a negative phase year of IODI corresponds to significant Pacific-Japan (P J) wavetrain, it is highly likely that the SST for the dipole may affect the precipitation in China through the wavetrain. Additionally, correlation analysis of links between SST dipole index of the Indian Ocean region and air temperature in China also shows good correlation between the former and wintertime temperature in southern China. 展开更多
关键词 Indian Ocean SSTA dipole indexes precipitation in raining seasons correlation analysis
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Research on the Correlation of the Fluctuating Density Gradient of the Compressible Flows
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作者 Y. Obikane 《Journal of Energy and Power Engineering》 2010年第7期27-31,共5页
This work is to study a role of the fluctuating density gradient in the compressible flows tbr the computational fluid dynamics (CFD). A new anisotropy tensor with the fluctuating density gradient is introduced, and... This work is to study a role of the fluctuating density gradient in the compressible flows tbr the computational fluid dynamics (CFD). A new anisotropy tensor with the fluctuating density gradient is introduced, and is used for an invariant modeling technique to model the turbulent density gradient correlation equation derived from the continuity equation. The modeling equation is decomposed into three groups proportional to the mean velocity, proportional to the mean strain rate, and proportional to the mean density. The characteristics of the correlation in a wake are extracted from the results by the two dimensional direct simulation, and shows the strong correlation with the vortices in the wake near the body. Thus, it can be concluded that the correlation of the density gradient is a significant parameter to describe the quick generation of the turbulent property in the compressible flows. 展开更多
关键词 Turbulence modeling density gradient correlation compressible.
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Study of the Firing Temperature of Marajoara Archaeological Ceramics by EPR Associated to INAA Data
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作者 Kelly P. Nunes Casimiro S. Munita +8 位作者 Rosimeiri G. Toyota Paulo T.M. Oliveira Nilo F. Cano Denise Schaan Oswaldo Baffa Luiz C. Oliveira Carlos A. Brunello Eduardo G. Neves Ce1ia C. Demartini 《Journal of Environmental Science and Engineering(A)》 2012年第9期1108-1116,共9页
The Marajó Island is the largest island of the Marajō archipelago, located in the north of Brazil. In this region, at the end of 19th century, it was identified an archaeological society named Marajora, which oc... The Marajó Island is the largest island of the Marajō archipelago, located in the north of Brazil. In this region, at the end of 19th century, it was identified an archaeological society named Marajora, which occupied the island from 400 to 1,350 AD. It was characterized by a ceramic style recognized by its beauty and exuberance. Until this moment, the physical and chemical analysis studies in this ceramics are scarce and this kind of studies may help archaeological studies performed in the island. With this purpose, this work presents a preliminary study of the firing temperature in the ceramics. For that, the elementary concentrations of 109 samples from Museu de Archaeology and Ethnology Museum of the University of Sáo Paulo and samples collected in the Marajá Island were studied. The samples were analyzed using instrumental neutron activation analysis in which the elemental concentration of Ce, Co, Cr, Cs, Eu, Fe, Hf, K, La, Lu, Na, Nd, Rb, Sc, Sm, Ta, Tb, Th, U, Yb and Zn were determined. The interpretation of the results was made using multivariate statistical approaches and showed the existence of three chemical groups. Some samples of each cluster were chosen for the determination of their firing temperatures by electron paramagnetic resonance, in order to verify if different firing temperatures was associated with different elemental groups of ceramic samples. The results showed that there are no statistical differences in the firing temperature between the samples from Archaeology and Ethnology Museum and the contemporary samples of the Marajá Island. 展开更多
关键词 Maraj6 island archaeological ceramics INAA EPR multivariate statistical analysis.
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Independent and Combined Effect of Some Soil Tillage Systems on Nitrogen and Carbon Concentration in Soil Structural Units of Haplic Chernozems
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作者 Margarita Nankova Peter Yankov 《Journal of Agricultural Science and Technology(B)》 2015年第7期465-476,共12页
This paper aimed at studying the effect of different types of soil tillage systems on the change of total carbon (C) and nitrogen (N) in the soil structural units of different size after dry structural analysis of... This paper aimed at studying the effect of different types of soil tillage systems on the change of total carbon (C) and nitrogen (N) in the soil structural units of different size after dry structural analysis of soil. The research was carried out in a 6-field rotation system (grain maize-wheat-sunflower-wheat-bean-wheat) at the end of the 2nd rotation. Six out of 24 soil tillage systems were selected; they were applied independently and in combination in the crop rotation. After that, they were compared to the system with constant deep plowing. So a total of seven soil tillage systems were investigated. The selected systems for main soil tillage were the following: plowing (control variant), disking, cutting, nil tillage (direct sowing), plowing-disking, plowing-nil tillage, disking-nil tillage. Three depths of 0-10, 10-20 and 20-30 cm were studied, as well as soil structural units were of the following sizes: 〉 10 mm, 10-5, 5-3, 3-1, 1-0.25 mm and 〈 0.25 mm. As a result of systematic implementation of different soil tillage systems, higher N and C concentrations were established by the layers according to constant plowing. Constant disking and its alternation with nil tillage increased the total N concentration with 15.6% and 11.1%, respectively, in comparison with the constant plowing. The same was valid for C concentration in soil, but the highest increase was established in the variants with constant cutting and nil tillage. The exceeding was with 14.0% and 13.2%, in comparison to constant plowing. The redistribution of N and C depending on the structural soil units was most expressed in the 0-10 cm and 10-20 cm layers. The highest amounts of C and N were found in the soil units with size less than 5 mm, mainly in the 〈 0.25 mm fraction. At depth of 20-30 cm, the role of the size of soil structural units for C and N redistribution decreased strongly. The values of C/N ratio were moderate only under the use of constant disking. This index was low under all other soil tillage systems. The correlation of total N with C in soil was high, positive and significant depending on the size of structural soil units and the tillage systems, as average for the investigated factors in this experiment. The minimal tillage and the tillage without turning of soil, used independently and in combination, had the highest contribution to preserving the organic matter in the haplic Chernozems of Dobrudzha region. 展开更多
关键词 Soil tillage systems soil C total soil N soil structural units.
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IDFT Numerical Simulation Method for Gaussian Rough Surface with Relatively Large Correlation Length
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作者 王廷剑 王黎钦 赵小力 《Transactions of Tianjin University》 EI CAS 2015年第3期216-222,共7页
A numerical simulation method based on inverse discrete Fourier transform(IDFT)is presented for generating Gaussian rough surface with a desired autocorrelation function(ACF). The probability density function of the h... A numerical simulation method based on inverse discrete Fourier transform(IDFT)is presented for generating Gaussian rough surface with a desired autocorrelation function(ACF). The probability density function of the height distribution of the generated Gaussian surface and the root-mean-square height of the rough surface are also considered. It is found that the height distribution of the generated surface follows the Gaussian distribution, the deviation of the root-mean-square height of the modeled rough surface from the desired value is smaller than that of Patir's method, and the autocorrelation function of the modeled surface is also in good agreement with the desired autocorrelation function. Compared with Patir's method, the modeled surface generated by the IDFT method is in better agreement with the desired autocorrelation function, especially when the correlation length is relatively large. 展开更多
关键词 numerical simulation Gaussian rough surface autocorrelation function root-mean-square height IDFT
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New Metrics from a Fractional Gravitational Field
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作者 Rami Ahmad El-Nabulsi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2017年第9期309-312,共4页
Agop et al. proved in Commun. Theor. Phys. (2008) that, a Reissner-Nordstrom type metric is obtained, if gauge gravitational field in a fractal spacetime is constructed by means of concepts of scale relativity. We p... Agop et al. proved in Commun. Theor. Phys. (2008) that, a Reissner-Nordstrom type metric is obtained, if gauge gravitational field in a fractal spacetime is constructed by means of concepts of scale relativity. We prove in this short communication that similar result is obtained if gravity in D-spacetime dimensions is fractionalized by means of the Glaeske-Kilbaz Saigo fractional. Besides, non-singular gravitational fields are obtained without using extra-dimensions. We present few examples to show that these gravitational fields hold a number of motivating features in spacetime physics. 展开更多
关键词 D-spacetime dimensions fractional gravitational field
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Optical trapping of metallic Rayleigh particle by combined beam
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作者 程科 钟先琼 向安平 《Optoelectronics Letters》 EI 2012年第1期76-80,共5页
Radiation forces and trapping stability of metallic (i.e. gold) Rayleigh particle by combined beam are analyzed, and the combined beam is formed by superimposing two partially coherent off-axis fiat-topped beams. Th... Radiation forces and trapping stability of metallic (i.e. gold) Rayleigh particle by combined beam are analyzed, and the combined beam is formed by superimposing two partially coherent off-axis fiat-topped beams. The dependences of radiation forces on off-axis distance parameter, correlation length and particle radius are illustrated by numerical examples. The results show that there exist critical values d0,c and or σ0,c for the combined beam. For 0〈d ≤ d0,c or 0〈σ0 ≤ σ0,c the Gaussianlike intensity profile takes place at the geometrical focal plane, so that the transverse gradient force can act as restoring force. As the off-axis distance parameter increases or the correlation length decreases, the maximal intensity, the radiation force and trapping stiffness become smaller, while the transverse and longitudinal trapping ranges become larger. In comparison with a single beam, the combined beam is more favourable for trapping metallic Rayleigh particle owing to the stronger trapping stiffness and the larger trapping range. 展开更多
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