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Effect of Size and Initial Water Content on the Effective Diffusion Coefficient during Convective Drying of Sweet Potato Cut into Cubic and Cylindrical Shapes
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作者 Ibrango Abdoul Salam Ouoba Kondia Honoré +3 位作者 Bama Désiré Traoré Yssa Zongo Karim Ouedraogo Salifou 《Journal of Materials Science and Chemical Engineering》 2024年第6期71-82,共12页
In this article, we investigated the influence of size and initial water content on the effective diffusion coefficient of sweet potatoes samples cut into cubic and cylindrical shapes. The sizes of the cubic samples a... In this article, we investigated the influence of size and initial water content on the effective diffusion coefficient of sweet potatoes samples cut into cubic and cylindrical shapes. The sizes of the cubic samples are 0.5, 1, 1.5, 1.75, 2, 2.5 and 3 cm edge with a respective initial water content of 2.7, 3.76, 3.48, 2.68, 3.28, 2.17 and 2.29 kg/kgms. For cylindrical samples, the radius is set at 0.5 cm and sample heights are 1, 1.5, 2, 2.5, 3, 3.5 and 4 cm with respective water contents of 2.2, 3.19, 2.85, 2.1, 2.17, 2.39 and 2.03 kg/kgms. The effective diffusion coefficients of cubic samples are of the order of 10−10 and 10−9 m2∙s−1 grew with sample edge. As for the cylindrical samples, the effective diffusion coefficients were of the order of 10−9 m2∙s−1 and there was no linear correlation between cylinder height and their effective diffusion coefficient. As for the examination of the initial water content on the effective diffusion coefficient, it turned out that the initial water content had no influence on the effective diffusion coefficient of the sweet potato samples. 展开更多
关键词 Effective Diffusion Coefficient Initial Water Content Sweet Potato cubic CYLINDRICAL
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使用鱼眼镜头制作QuickTime CubicVR 被引量:3
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作者 张燕翔 吴敏 邵敏勇 《系统仿真学报》 CAS CSCD 2001年第S2期568-569,共2页
讨论了最新的QuickTime CubicVR技术的几种合成方法,并就其中最简单易行的鱼眼镜头法进行了深入的探讨,得到了这种方法的数学模型,为以后的软件开发奠定了基础。
关键词 鱼眼镜头 QuickTimecubicVR 数学模型
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基于形态学算子的Cubic图像缩放方法 被引量:1
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作者 王宏文 郝春华 李晓阳 《激光杂志》 CAS CSCD 北大核心 2014年第11期42-44,共3页
立方卷积插值(Cubic算法)是一种常用的图像缩放方法。为了使喷码机喷印图像更加清晰可见,改善Cubic算法边缘模糊、分辨率低等不足,本文将形态学算子中的腐蚀运算与Cubic算法结合,以此进行了理论分析和实验验证。结果表明,此方法对提高... 立方卷积插值(Cubic算法)是一种常用的图像缩放方法。为了使喷码机喷印图像更加清晰可见,改善Cubic算法边缘模糊、分辨率低等不足,本文将形态学算子中的腐蚀运算与Cubic算法结合,以此进行了理论分析和实验验证。结果表明,此方法对提高图像边缘的清晰度和图像质量有明显效果。 展开更多
关键词 图像缩放 形态学算子 腐蚀运算 立方卷积插值
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Cubic B样条旋转曲面的自由绘制技术 被引量:3
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作者 韩丽 Raffaele De Amicis 《小型微型计算机系统》 CSCD 北大核心 2009年第7期1441-1444,共4页
随着基于样条曲线的模型逐渐成为CAGD的主要研究对象,进一步带动了高度自由曲面建模技术的发展.本文描述一个新颖、直观的旋转曲面绘制技术,它支持三次B样条的自由输入作为轮廓线,并通过提取的样点矢量以及最小方差逼近方法形成旋转轴,... 随着基于样条曲线的模型逐渐成为CAGD的主要研究对象,进一步带动了高度自由曲面建模技术的发展.本文描述一个新颖、直观的旋转曲面绘制技术,它支持三次B样条的自由输入作为轮廓线,并通过提取的样点矢量以及最小方差逼近方法形成旋转轴,利用轴上测量点的切线方向确定各个圆平面,从而建立了平面上旋转坐标矩阵,最终插值空间球面样点生成双三次B样条曲面.实验结果有效地验证了此技术的高效性. 展开更多
关键词 旋转曲面 三次B样条 逼近 插值
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基于Hermite Cubics的预滤波器与双正交平衡系统
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作者 程蓉 赵宇 李万社 《广州大学学报(自然科学版)》 CAS 2009年第3期16-19,共4页
首先将正交多小波系统的平衡性理论及预滤波理论推广到双正交系统,在此基础上,从不具有平衡性的Hermite Cubics双正交多小波出发,得到两组使系统的"低通"滤波器保持三阶多项式信号的预滤波器,最后给出一组基于Hermite Cubics... 首先将正交多小波系统的平衡性理论及预滤波理论推广到双正交系统,在此基础上,从不具有平衡性的Hermite Cubics双正交多小波出发,得到两组使系统的"低通"滤波器保持三阶多项式信号的预滤波器,最后给出一组基于Hermite Cubics系统的具有一阶平衡性的双正交多小波系统. 展开更多
关键词 双正交多小波 预滤波 平衡性 HERMITE cubics
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用Bi-cubic插值法改进H.264视频质量
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作者 黄晓宇 肖伟平 余新宇 《湖南工程学院学报(自然科学版)》 2005年第2期66-68,共3页
通过对H.264标准的分析,提出了用Bi-cubic插值法来改进H.264标准中推荐的插值算法,以使H.264视频质量达到更好的标准,实验表明方案是可行的.
关键词 H.264 Bi—cubic插值法 双线性插值法
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基于Cubic映射的灰狼优化算法及应用 被引量:20
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作者 张孟健 张浩 +1 位作者 陈曦 杨靖 《计算机工程与科学》 CSCD 北大核心 2021年第11期2035-2042,共8页
针对标准的灰狼优化算法GWO对于复杂优化问题的求解易陷入局部最优的缺点,从混沌初始化和非线性控制策略2个角度,提出一种基于Cubic映射和反向学习的灰狼优化算法COGWO。首先,利用Cubic映射和反向学习策略对种群进行初始化,并通过非线... 针对标准的灰狼优化算法GWO对于复杂优化问题的求解易陷入局部最优的缺点,从混沌初始化和非线性控制策略2个角度,提出一种基于Cubic映射和反向学习的灰狼优化算法COGWO。首先,利用Cubic映射和反向学习策略对种群进行初始化,并通过非线性参数控制策略来调节寻优过程中的参数;然后,对6种基准测试函数进行寻优实验,实验结果表明,COGWO算法具有更好的收敛精度、收敛速度和稳定性;最后,将COGWO算法应用到了实际的工程优化问题中。 展开更多
关键词 灰狼优化算法 cubic映射 反向学习 拉伸弹簧设计 非线性
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基于Cubic Hermite的改进EMD算法 被引量:4
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作者 李奇 刘自然 +1 位作者 颜丙生 宋宇宙 《机床与液压》 北大核心 2021年第21期186-190,共5页
传统经验模态分解(EMD)算法求取IMF分量是依据信号极值点通过三次样条插值拟合上下包络线,然后求其局部均值,存在端点效应问题,严重影响部分特征信号的提取。针对此类问题,提出一种利用Cubic Hermite插值改进EMD过程的方法,并通过LabVIE... 传统经验模态分解(EMD)算法求取IMF分量是依据信号极值点通过三次样条插值拟合上下包络线,然后求其局部均值,存在端点效应问题,严重影响部分特征信号的提取。针对此类问题,提出一种利用Cubic Hermite插值改进EMD过程的方法,并通过LabVIEW平台实现改进后的经验模态分解。采用频率和幅值不同的2种叠加正弦信号进行算法验证,结果表明:该算法能有效缓解包络线过冲、欠冲现象,抑制低频信号的端点效应和端点附近局部失真问题。 展开更多
关键词 经验模态分解 端点效应 cubic Hermite插值 IMF分量 LabVIEW
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AXISYMMETRIC CONTACT PROBLEM OF CUBIC QUASICRYSTALLINE MATERIALS 被引量:14
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作者 Zhou Wangmin Fan Tianyou Yin Shuyuan 《Acta Mechanica Solida Sinica》 SCIE EI 2002年第1期68-74,共7页
The axisymmetric elasticity theory of cubic quasicrystal was developed in Ref. [1]. The axisymmetric elasticity problem of cubic quasicrystal is reduced to a single higher-order partial differential equation by introd... The axisymmetric elasticity theory of cubic quasicrystal was developed in Ref. [1]. The axisymmetric elasticity problem of cubic quasicrystal is reduced to a single higher-order partial differential equation by introducing a displacement function, based on which, the exact analytic solutions for the elastic field of an axisymmetric contact problem of cubic quasicrystalline materials are obtained for universal contact stress or contact displacement. The result shows that if the contact stress has order - 1/2 singularity on the edge of the contact domain, die contact displacement is a constant in the contact domain. Conversely, if the contact displacement is a constant, the contact stress must have order - 1/2 singularity on the edge of die contact domain. 展开更多
关键词 cubic quasicrystal AXISYMMETRY contact problem
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利用数据挖掘技术改进TCP CUBIC拥塞控制算法 被引量:8
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作者 张錋 毛澍 +3 位作者 李彦庆 张晶晶 武宏斌 韩啸 《计算机应用研究》 CSCD 北大核心 2018年第10期3044-3047,共4页
TCP CUBIC拥塞控制算法无法主动判断拥塞和预测丢包。为解决这一难题,算法首先采集网络节点数据,利用多维关联挖掘方法建立模型,引用RTT最大值和最小值变化率判定网络拥塞;然后划分拥塞等级,利用动态神经网络算法训练模型,确定拥塞窗口... TCP CUBIC拥塞控制算法无法主动判断拥塞和预测丢包。为解决这一难题,算法首先采集网络节点数据,利用多维关联挖掘方法建立模型,引用RTT最大值和最小值变化率判定网络拥塞;然后划分拥塞等级,利用动态神经网络算法训练模型,确定拥塞窗口的立方增长因子λ和线性增长参数S数值大小,制定不同策略主动调整拥塞窗口增长速度,利用贝叶斯学习推理策略,动态学习预测连接路径丢包概率;最后,结果表明改进算法能有效调整拥塞和预测丢包。 展开更多
关键词 数据挖掘 关联挖掘 拥塞控制 往返时延
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Electrochemical Generation of Cubic Shaped Nano Zn_2SnO_4 Photocatalysts 被引量:5
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作者 Chandrappa K.Govindappa Venkatesha T.Venkatarangaiah Sharifah B.Abd Hamid 《Nano-Micro Letters》 SCIE EI CAS 2013年第2期101-110,共10页
In this contribution, an efficient and simple two-step hybrid electrochemical-thermal route was developed for the synthesis of cubic shaped Zn_2SnO_4 (ZTO) nanoparticles using aqueous sodium bicarbonate(NaHCO_3) and s... In this contribution, an efficient and simple two-step hybrid electrochemical-thermal route was developed for the synthesis of cubic shaped Zn_2SnO_4 (ZTO) nanoparticles using aqueous sodium bicarbonate(NaHCO_3) and sodium stannate(Na_2SnO_3) electrolyte. The sacrificial Zn was used as anode and cathode in an undivided cell under galvanostatic mode at room temperature. The bath concentration and current density were respectively varied from 30 to 120 mmol and 0.05 to 1.5 A/dm^2. The electrochemically generated precursor was calcined for an hour at different range of temperature from 60 to 600. The crystallite sizes in the range of 24-53 nm were calculated based on Debye-Scherrer equation. Scanning electron microscope and transmission electron microscopy results reveal that all the particles have cubic morphology with diameter of40-50 nm. The as-prepared ZTO samples showed higher catalytic activity towards the degradation of methylene blue(MB) dye, and 90% degradation was found for the sample calcined at 600, which is greater than that of commercial TiO_2-P25 photocatalysts. The photodegradation efficiency of ZTO samples was found to be a function of exposure time and the dye solution p H value. These results indicate that the ZTO nanoparticles may be employed to remove dyes from wastewater. 展开更多
关键词 ELECTROCHEMISTRY Zn2SnO4 PHOTOCATALYST cubic NANOPARTICLE
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A comparison of piecewise cubic Hermite interpolating polynomials,cubic splines and piecewise linear functions for the approximation of projectile aerodynamics 被引量:3
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作者 C.A.Rabbath D.Corriveau 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2019年第5期741-757,共17页
Modelling and simulation of projectile flight is at the core of ballistic computer software and is essential to the study of performance of rifles and projectiles in various engagement conditions.An effective and repr... Modelling and simulation of projectile flight is at the core of ballistic computer software and is essential to the study of performance of rifles and projectiles in various engagement conditions.An effective and representative numerical model of projectile flight requires a relatively good approximation of the aerodynamics.The aerodynamic coefficients of the projectile model should be described as a series of piecewise polynomial functions of the Mach number that ideally meet the following conditions:they are continuous,differentiable at least once,and have a relatively low degree.The paper provides the steps needed to generate such piecewise polynomial functions using readily available tools,and then compares Piecewise Cubic Hermite Interpolating Polynomial(PCHIP),cubic splines,and piecewise linear functions,and their variant,as potential curve fitting methods to approximate the aerodynamics of a generic small arms projectile.A key contribution of the paper is the application of PCHIP to the approximation of projectile aerodynamics,and its evaluation against a set of criteria.Finally,the paper provides a baseline assessment of the impact of the polynomial functions on flight trajectory predictions obtained with 6-degree-of-freedom simulations of a generic projectile. 展开更多
关键词 Aerodynamic coefficients PIECEWISE POLYNOMIAL FUNCTIONS cubic splines Curve fitting PIECEWISE linear FUNCTIONS PIECEWISE cubic HERMITE interpolating POLYNOMIAL PROJECTILE modelling and simulation Fire control inputs Precision Ballistic computer software
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Al-incorporation into Li7La3Zr2O12 solid electrolyte keeping stabilized cubic phase for all-solid-state Li batteries 被引量:4
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作者 Changbin Im Dongwon Park +1 位作者 Hosung Kim Jaeyoung Lee 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2018年第5期1501-1508,共8页
We observe the influence of AI occupancies in Li sites on the formation process of the garnet solid elec- trolyte of Li_7La_3Zr_2O_12 (LLZO). A direct incorporation of AI is first promoted in a Li-insufficient garne... We observe the influence of AI occupancies in Li sites on the formation process of the garnet solid elec- trolyte of Li_7La_3Zr_2O_12 (LLZO). A direct incorporation of AI is first promoted in a Li-insufficient garnet solid electrolyte during the calcination process of 850 ℃ and then the cubic phase of LLZO is obtained after successive annealing step of 1000 ℃. Comparing to pristine LLZO, AI incorporated LLZO shows less formation of Li_2CO_3, keeping crystallographic and physicochemical properties. This AI incorporation im- proves both the ionic conductivity and interfacial resistance to poisoning procedure. 展开更多
关键词 Li_7La_3Zr_2O_12 AI incorporation Garnet solid electrolyte cubic phase
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Generation of breathing solitons in the propagation and interactions of Airy–Gaussian beams in a cubic–quintic nonlinear medium 被引量:5
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作者 Weijun Chen Ying Ju +2 位作者 Chunyang Liu Liankai Wang Keqing Lu 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第11期528-533,共6页
Using the split-step Fourier transform method, we numerically investigate the generation of breathing solitons in the propagation and interactions of Airy–Gaussian(AiG) beams in a cubic–quintic nonlinear medium in... Using the split-step Fourier transform method, we numerically investigate the generation of breathing solitons in the propagation and interactions of Airy–Gaussian(AiG) beams in a cubic–quintic nonlinear medium in one transverse dimension. We show that the propagation of single AiG beams can generate stable breathing solitons that do not accelerate within a certain initial power range. The propagation direction of these breathing solitons can be controlled by introducing a launch angle to the incident AiG beams. When two AiG beams accelerated in opposite directions interact with each other,different breathing solitons and soliton pairs are observed by adjusting the phase shift, the beam interval, the amplitudes,and the light field distribution of the initial AiG beams. 展开更多
关键词 cubic-quintic nonlinear medium Airy-Gaussian beams propagation and interactions breathing solitons
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Displacement Response Reconstruction of Slender Flexible Structures Based on Cubic Spline Fitting Method 被引量:3
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作者 HAN Qing-hua MA Ye-xuan +1 位作者 FENG Xin-xin XU Wan-hai 《China Ocean Engineering》 SCIE EI CSCD 2019年第2期226-236,共11页
How to reconstruct a dynamic displacement of slender flexible structures is the key technology to develop smart structures and structural health monitoring(SHM), which are beneficial for controlling the structural vib... How to reconstruct a dynamic displacement of slender flexible structures is the key technology to develop smart structures and structural health monitoring(SHM), which are beneficial for controlling the structural vibration and protecting the structural safety. In this paper, the displacement reconstruction method based on cubic spline fitting is put forward to reconstruct the dynamic displacement of slender flexible structures without the knowledge of modeshapes and applied loading. The obtained strains and displacements are compared with the results calculated by ABAQUS to check the method's validity. It can be found that the proposed method can accurately identify the strains and displacement of slender flexible structures undergoing linear vibrations, nonlinear vibrations, and parametric vibrations. Under the concentrated force, the strains of slender flexible structures will change suddenly along the axial direction. With locally densified measurement points, the present reconstruction method still works well for the strain concentration problem. 展开更多
关键词 DISPLACEMENT RECONSTRUCTION cubic SPLINE FITTING slender flexible structures linear vibrations PARAMETRIC vibrations nonlinear vibrations
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First-principles study of the electronic structure and optical properties of cubic Perovskite NaMgF_3 被引量:3
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作者 李贞丽 安辛友 +4 位作者 程新路 王雪敏 张红 彭丽萍 吴卫东 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第3期469-474,共6页
The structural, electronic, and optical properties of cubic perovskite NaMgF3 are calculated by plane-wave pseudopo- tential density functional theory. The calculated lattice constant a0, bulk modulus B0, and the deri... The structural, electronic, and optical properties of cubic perovskite NaMgF3 are calculated by plane-wave pseudopo- tential density functional theory. The calculated lattice constant a0, bulk modulus B0, and the derivative of bulk modulus B~ are 3.872/~, 78.2 GPa, and 3.97, respectively. The results are in good agreement with the available experimental and theo- retical values. The electronic structure shows that cubic NaMgF3 is an indirect insulator with a wide forbidden band gap of Eg = 5.90 eV. The contribution of the different bands is analyzed by total and partial density of states curves. Population analysis of NaMgF3 indicates that there is strong ionic bonding in the MgF2 unit, and a mixture of ionic and weak covalent bonding in the NaF unit. Calculations of dielectric function, absorption coefficient, refractive index, electronic energy loss spectroscopy, optical reflectivity, and conductivity are also performed in the energy range 0 to 70 eV. 展开更多
关键词 density functional theory cubic perovskite NaMgF3 electronic properties optical properties
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Industrial growth of yttria-stabilized cubic zirconia crystals by skull melting process 被引量:3
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作者 徐家跃 雷秀云 +4 位作者 蒋新 何庆波 房永征 张道标 何雪梅 《Journal of Rare Earths》 SCIE EI CAS CSCD 2009年第6期971-974,共4页
We reported the development of a Ф100 cm growth apparatus for skull melting growth of yttria-stabilized cubic zirconia(YSZ) crystals and more than 1000 kg crystals have been grown in the furnace each time.The growth ... We reported the development of a Ф100 cm growth apparatus for skull melting growth of yttria-stabilized cubic zirconia(YSZ) crystals and more than 1000 kg crystals have been grown in the furnace each time.The growth conditions were optimized and the structure of the as-grown crystals was characterized by X-ray diffraction.The transmittance of 15 mol.% yttria-stabilized cubic zirconia crystal was nearly 80% in the range of 400–1600 nm.The refractive indices were measured and fitted the Sellmeier equation whi... 展开更多
关键词 yttria-stabilized cubic zirconia crystal growth skull melting process rare earths
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1∶2 INTERNAL RESONANCE OF COUPLED DYNAMIC SYSTEM WITH QUADRATIC AND CUBIC NONLINEARITIES 被引量:3
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作者 陈予恕 杨彩霞 +1 位作者 吴志强 陈芳启 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第8期917-924,共8页
The 1:2 internal resonance of coupled dynamic system with quadratic and cubic nonlinearities is studied. The normal forms of this system in 1 :2 internal resonance were derived by using the direct method of normal for... The 1:2 internal resonance of coupled dynamic system with quadratic and cubic nonlinearities is studied. The normal forms of this system in 1 :2 internal resonance were derived by using the direct method of normal form. In the normal,forms, quadratic and cubic nonlinearities were remained. Based on a new convenient transformation technique, the 4-dimension bifurcation equations were reduced to 3-dimension. A bifurcation equation with one-dimension was obtained. Then the bifurcation behaviors of a universal unfolding were studied by using the singularity theory. The method of this paper can be applied to analyze the bifurcation behavior in strong internal resonance on 4-dimension center manifolds. 展开更多
关键词 quadratic and cubic nonlinearities Normal Form 1 : 2 internal resonance
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Energy exchange between (3+1)D colliding spatiotemporal optical solitons in dispersive media with cubic-quintic nonlinearity 被引量:2
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作者 杨红 唐翌 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第3期1008-1013,共6页
We investigate the energy exchange between (3+1)D colliding spatiotemporal solitons (STSs) in dispersive media with cubic-quintic (CQ) nonlinearity by numerical simulations. Energy exchange between two (3+1)... We investigate the energy exchange between (3+1)D colliding spatiotemporal solitons (STSs) in dispersive media with cubic-quintic (CQ) nonlinearity by numerical simulations. Energy exchange between two (3+1)D head on colliding STSs caused by their phase difference is observed, just as occurring in other optical media. Moreover, energy exchange between two head-on colliding STSs with different speeds is firstly shown in the CQ and saturable media. This phenomenon, we believe, may arouse some interest in the future studies of soliton collision in optical media. 展开更多
关键词 spatiotemporal solitons cubic-quantic nonlinearity energy exchange
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The electrical properties of sulfur-implanted cubic boron nitride thin films 被引量:2
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作者 邓金祥 秦扬 +4 位作者 孔乐 杨学良 李廷 赵卫平 杨萍 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第4期458-460,共3页
Cubic boron nitride (c-BN) thin films are deposited on p-type Si wafers using radio frequency (RF) sputtering and then doped by implanting S ions. Wile implantation energy of the ions is 19 keV, and the implantati... Cubic boron nitride (c-BN) thin films are deposited on p-type Si wafers using radio frequency (RF) sputtering and then doped by implanting S ions. Wile implantation energy of the ions is 19 keV, and the implantation dose is between 1015 ions/cm2 and 1016 ions/cm2. The doped c-BN thin films are then annealed at a temperature between 400℃ and 800℃. The results show that the surface resistivity of doped and annealed c-BN thin films is lowered by two to three orders, and the activation energy of c-BN thin films is 0.18 eV. 展开更多
关键词 cubic boron nitride ion implantation surface resistivity activation energy
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