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1.
模型飞行验证系统是为更加有效地开展模型自由飞试验研究而设计的通用试验系统,测控(TT C)与信息传输系统是其信息保障的核心。本文在充分考虑模型自由飞试验特点的基础上,重点研究了模型飞行验证系统研制过程中的测控与信息传输技术,介绍了其工作原理及实现方法,并对部分结果进行分析。  相似文献   

2.
吕洪发  王惠南 《光子学报》2006,35(12):1846-1849
根据1/2波节自聚焦(GRIN)透镜中光的传输特性,提出了一种新颖的测量微小角位移的模型,通过对模型中光线传输和几何关系的理论分析,推导了待测角位移与光耦合效率之间的传递函数.针对模型对测量范围的限制,提出了一种可行的拓宽测量范围的方法.研究结果表明,该模型不但测量范围宽,而且测量准确度高,线性度好.  相似文献   

3.
在“星光Ⅱ”装置上,采用双孔柱腔靶研究辐射在空腔中轴向传输变化特性.提出“漏水管”辐射输运的简化模型,用来分析X射线在空腔中的传输的实验结果。分析结果表明,简化模型与实验结果基本相符.X射线输运的结果是输运末端的X射线减弱,辐射持续的时间增大,等离子体弛豫时间增大 关键词: 双孔柱腔靶 辐射传输 “漏水管”模型  相似文献   

4.
杨志春  吴锋  郭方中  张春萍 《物理学报》2011,60(8):84303-084303
将辛数学引入热声系统网络模型的处理,通过对热声系统网络传输矩阵的分析,证明系统中等温流体管道内工质运动的传输矩阵为辛矩阵.存在温度梯度的热声回热器中气体工质微团的传输矩阵不是辛矩阵,但是可以通过变量代换将传输矩阵转换为辛矩阵,使整个热声系统网络传输都可用辛矩阵传输来表示.辛对称的形式有助于热声系统网络模型的分析与计算. 关键词: 辛 热声 网络模型 传输矩阵  相似文献   

5.
被光阑衍射部分偏振高斯-谢尔模型光束的远场特性   总被引:5,自引:0,他引:5  
潘留占 《光学学报》2006,26(8):250-1255
从部分相干光的传输理论出发,采用光束相干-偏振矩阵方法研究了被光阑衍射部分偏振高斯-谢尔模型光束的远场特性,对远场偏振和光强特性作了详细的数值计算和物理分析。研究结果表明,光阑衍射部分偏振高斯-谢尔模型光束的远场特性与光阑截断参量、光的空间相干性和衍射角有关。并与自由空间的传输特性和以前的工作作了比较分析。  相似文献   

6.
郑羽  赵宣  李静  付孝洪  王金海  李红志  刘宁 《物理学报》2014,63(4):40507-040507
由于环境的要求,深海走航抛弃式测量仪器信号传输大多使用有线信道,然而,信道的电阻抗随放线长度不断变化,严重影响了深海走航抛弃式测量仪器信道传输的稳定性.本文以国家海洋技术中心自主研发的走航抛弃式温度、盐度、湿度(XCTD)剖面仪的传输信道为原型,提出了一种动态分析有线信道对传输信号幅值和相位影响的方法.首先推导出各电路参数随信道长度变化的规律,建立简化的传输电路模型和该模型的传输函数.通过定性分析得出传输频率、分布电容和缠绕电感对信号相位的影响.利用MATLAB软件分析XCTD在动态放线过程中信道对信号幅值和相位的影响.研究结果可进一步指导抛弃式走航测量系统的电路设计,提高测量数据的精度和信号传输的稳定性.  相似文献   

7.
光孤子传输模型及其应用   总被引:3,自引:0,他引:3  
杨祥林  王发强 《光学学报》1997,17(5):59-564
从周期性集中放大系统孤子传输的基本方程出发,建立了比平均孤子模型适用范围更广、更精确的传输模型,运用微扰方法对孤子到达时间抖动作了研究,并与平均孤子模型给出的结果作了比较。  相似文献   

8.
考虑硅通孔的三维集成电路热传输解析模型   总被引:1,自引:0,他引:1       下载免费PDF全文
朱樟明  左平  杨银堂 《物理学报》2011,60(11):118001-118001
基于不考虑硅通孔的N层叠芯片的一维热传输解析模型,提出了硅通孔的等效热模型,获得了考虑硅通孔的三维集成电路热传输解析模型,并采用Matlab软件验证分析了硅通孔对三维集成电路热管理的影响.分析结果表明,硅通孔能有效改善三维集成电路的散热,硅通孔的间距增大将使三维集成电路的温升变大. 关键词: 三维集成电路 热管理 硅通孔 等效热模型  相似文献   

9.
张克涵  阎龙斌  闫争超  文海兵  宋保维 《物理学报》2016,65(4):48401-048401
文章对基于磁共振的水下非接触式电能传输系统在海水中的传输机理以及电涡流损耗进行了分析. 首先基于互感模型, 建立了空气中磁共振非接触式电能传输系统的数学模型, 分析了系统的频率特性, 从理论上对频率分裂现象进行了解释. 然后针对海水环境, 通过麦克斯韦方程组建立系统的数学模型, 通过级数展开, 略去高阶项, 得到计算电涡流损耗的近似公式, 分析了电涡流损耗与线圈半径、谐振频率、传输距离、磁感应强度的关系, 为水下非接触式电能传输系统的总体设计提供了理论依据. 最后通过实验验证了在空气中和海水中进行非接触式电能传输的异同, 以及电涡流损耗与各项参数的关系. 实验表明: 在空气中当传输距离为50 mm、传输功率为100 W时, 效率在80%以上; 在海水中当传输距离为50 mm、传输功率为100 W时, 效率约为67%, 说明基于磁共振的水下非接触式电能传输系统在海水中也有很好的应用前景.  相似文献   

10.
X射线在毛细导管中传输的理论研究   总被引:2,自引:0,他引:2       下载免费PDF全文
陈宝振 《物理学报》2000,49(10):1933-1937
给出了X射线在毛细导管中传输特性的简明而系统的理论描述.在这个理论描述的基础上,建 立了X射线在毛细导管中传输的计算模型,编制了X射线在毛细导管中传输的计算程序.利用 编制的X射线在毛细导管中传输计算程序得到的数值结果和实验结果符合得很好. 关键词: 毛细导管 X射线 传输模型  相似文献   

11.
A unified algebraic approach to both the hard-core Fermi- and Bose-Hubbard models is extended to boththe finite- and infinite-site with periodic condition cases. Excitation energies and the corresponding wavefunctions ofboth the models with nearest neighbor hopping are exactly derived by using a new and simple algebraic method. It isfound that spectra of both the models are determined simply by eigenvalue problem of N × N hopping matrix, where Nis the number of sites for finite system or the period of sites for infinite system.  相似文献   

12.
We consider two single-species reaction-diffusion models on one-dimensional lattices of lengthL: the coagulation-decoagulation model and the annihilation model. For the coagulation model the system of differential equations describing the time evolution of the empty interval probabilities is derived for periodic as well as for open boundary conditions. This system of differential equations grows quadratically withL in the latter case. The equations are solved analytically and exact expressions for the concentration are derived. We investigate the finite-size behavior of the concentration and calculate the corresponding scaling functions and the leading corrections for both types of boundary conditions. We show that the scaling functions are independent of the initial conditions but do depend on the boundary conditions. A similarity transformation between the two models is derived and used to connect the corresponding scaling functions.  相似文献   

13.
谢峰  林万涛  林一骅  莫嘉琪 《中国物理 B》2011,20(1):10208-010208
A class of delayed oscillators of El Ni?o-southern oscillation (ENSO) models is considered. Using the delayed theory, the perturbed theory and other methods, the asymptotic expansions of the solutions for ENSO models are obtained and the asymptotic behaviour of solution of corresponding problem is studied.  相似文献   

14.
用坐标Bethe ansatz方法详细研究了开边界条件下一类新Hubbard模型的可积性问题. 得到了系统的能谱、可积边界条件和Bethe ansatz方程.  相似文献   

15.
Ferromagnetic Ising models on the lattice Sierpinski gasket are considered. We prove the Dobrushin-Shlosmann mixing condition and discuss corresponding properties of the stochastic Ising models.  相似文献   

16.
油气水三相流中的复杂相态及压力降研究   总被引:3,自引:0,他引:3  
将水平管划分为三个测量段,以空气、水和高粘度油体为工质,研究了油气水三相流中由流动引起的液-液复杂相态及其所对应的三相流压力降。试验研究发现,油气水三相流在三个测量段中可由流动引起不同的液-液相态,致使对应于相同的油、气、水三相体积通量,三相流阻力损失存在多值性。对不同的液-液相态建立了与之适应的阻力损失计算模型,模型预测结果与试验结果吻合  相似文献   

17.
Viscosity is an important property which could determine the flow liquid metal characteristics and reflect the liquidus structure. Therefore, the existence of an accurate model is necessary to calibrate the experimental measurement value of viscosity. At present, many models have been proposed to estimate the viscosity of pure liquid metal, the temperature dependence of viscosity and the viscosity of multicomponent alloy systems. In this paper, a number of the familiar models are given, and their fundamental modelling theory, model characteristics and applicability are adequately discussed. The general semi-empirical models which have been very successful in predicting the viscosity of pure liquid metal are divided into Andrade and Eyring two branches. The common multivariate melt viscosity prediction models are mostly based on the fundamental molecular theory method, which combines the thermodynamic parameters and achieves good validity. It is expected in the final that the corresponding viscosity prediction model of phase diagram might be more likely to replace the independent general prediction equation in the future.  相似文献   

18.
We present Bianchi type-I cosmological models in the presence of generalized Chaplygin gas and perfect fluid for early and late time epochs. Exact solutions of Einstein’s field equations for this model are obtained. The general solutions of gravitational field equations are expressed in an exact parametric form, with average scale factor as parameter. In the limiting cases of small and large values of the average scale factor, the solutions of the field equations are expressed in exact analytic forms. Moreover, this model predicts that the expansion of Universe is accelerating for the late times. The physical and geometrical properties of the corresponding cosmological models are discussed.  相似文献   

19.
Ali Dogan 《哲学杂志》2019,99(15):1825-1848
The surface tensions of ternary and quaternary systems of Sn-based Pb-free solder alloys have been calculated using geometric models, such as Muggianu, Kohler, Chou’s general solution model (GSM), Toop, Guggenheim, ideal Butler and Butler models. It is observed from the calculation carried out in the present work that Sb and Bi contents decrease the surface tension of the solder alloys Sn-Zn-Sb-Bi. It is inferred from the statistical analysis that the best agreement between the experimental results and the corresponding calculated values of the surface tensions is generally observed in GSM and Muggianu models among the geometric models. Whereas Muggianu model is the most appropriate. Relatively good agreements have been observed between models considered in this study and experimental data.  相似文献   

20.
Zhao X  Gang T 《Ultrasonics》2009,49(1):126-27
A nonparaxial multi-Gaussian beam model is proposed in order to overcome the limitation that paraxial Gaussian beam models lose accuracy in simulating the beam steering behavior of phased array transducers. Using this nonparaxial multi-Gaussian beam model, the focusing and steering sound fields generated by an ultrasonic linear phased array transducer are calculated and compared with the corresponding results obtained by paraxial multi-Gaussian beam model and more exact Rayleigh-Sommerfeld integral model. In addition, with help of this novel nonparaxial method, an ultrasonic measurement model is provided to investigate the sensitivity of linear phased array transducers versus steering angles. Also the comparisons of model predictions with experimental results are presented to certify the accuracy of this provided measurement model.  相似文献   

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