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不闭合磁芯的tesla变压器初次级线圈电感估算
石磊,樊亚军,
强激光与粒子束 , 2013,
Abstract: ?对具有不闭合磁芯的tesla变压器磁路进行了研究,计算了tesla变压器磁路中磁力线分布以及各处磁感应强度分布,结果表明:在磁芯所在位置,磁力线主要集中在磁芯内部;在内外筒磁芯之间,磁力线主要分布在初次级线圈以外磁芯两端之间的空隙中。实际的tesla变压器漏磁较小,分析了在没有漏磁的理想情况下tesla变压器不闭合磁芯对初、次级线圈电感的影响,并给出了初、次级线圈电感的估算公式,利用估计公式得出的结果与实际测量对比,误差范围在15%以内,该公式在tesla变压器设计和参数估算时不失为一种简便易行的处理方法。
失效卫星空间近距离接近的位姿联合确定
熊智,姚小松,
南京航空航天大学学报 , 2013,
Abstract:
热漏、内不可逆性和传热规律对卡诺热泵最优性能的影响
薛蒙,陈林根,,
工程热物理学报 , 1997,
Abstract:
热阻对闭式燃气轮机回热循环性能的影响
陈林根,,
工程热物理学报 , 1995,
Abstract:
土壤液化势的剪切波速判别法
石兆吉,寿松,万玲
岩石工程学报 , 1993,
Abstract: <正>一、前言剪切波速vs在我国地震工程和岩土工程中的应用日益普遍,如判别砂性土的液化势等,但这种方法在国际上尚未得到统一的认识。某些学者认为,不可直接用vs预测砂土的液化势,而只能用间接的方法进行.其根据是,在试验室内得不到单一的地震应力比与剪切波速的关系,这种关系与砂土的类型有关。笔者对这些试验结果曾进行了仔细研究,指出这些试验存在的问题和得不到合理结果的原因,同时提出了合理的试验方法,得到了地震应力比与vs之间的单一定量关系,从而验证了用vs预测砂性土液化势的物理基础.
饱和砂土振后再固结体应变的变化规律
石兆吉,万玲,寿松
岩石工程学报 , 1989,
Abstract: <正>砂土地震液化灾害的一种表现形式是饱和砂土层因现因结造成的沉陷,宏观震害资料表明,因现固结引起的地表下沉可达50-100cm.
形成线脉冲压缩技术在超宽谱技术中的应用
,石磊,樊亚军,夏文锋
强激光与粒子束 , 2013,
Abstract: ?分析了基于同轴blumlein线的高功率脉冲源对低阻抗短形成线充电、实现脉冲压缩的基本原理,给出了理想情况下,脉冲压缩后输出的高功率超宽谱脉冲电压、功率增益及能量效率计算公式。利用电路仿真软件建立了脉冲压缩电路模型,通过模拟验证了理论分析。模拟了实际主脉冲波形对输出脉冲的影响,结果表明:低阻抗压缩线充电时间变长、充电电压峰值降低;通过在前级脉冲源与脉压形成线之间增加一定长度传输线,可以有效提高压缩线充电电压。针对典型的同轴blumlein线高功率脉冲源——紧凑tesla型高功率脉冲源ckp-1000,设计了脉冲压缩装置和测量系统,建立了完整的脉冲压缩实验系统,开展了脉冲压缩试验。该脉压系统可将4.5ns输入脉冲压缩为前沿940ps、半高宽约1ns的亚纳秒脉冲,实现了约2.2倍的功率增益。实验数据与理论分析基本吻合。
一维双基线相位干涉测向公式的准确解
Accurate Solution of DF Formula for Phase Interference with One-Dimensional Double Baseline
 [PDF]


Journal of Antennas (JA) , 2012, DOI: 10.12677/ja.2012.11002
Abstract:

摘  要:在利用径向距离与相位之间的对应关系给出相差定位方程的基础上,应用余弦定理所给出的三角方程,且仅通过简单的数学变形处理即得到了求解目标位置的线性方程组,并由所解得的目标位置获得了一维双基线相位干涉阵列的测向公式准确解。整个分析过程借助于路程差与相位差测量项的等价性,在不涉及对整周数和鉴相电路相位差值计算的情况下,实现了对准确解的验证和测量误差的分析。本文的研究为校正现有按平行入射波假定所得到的近似解的测量精度提供了理论依据。





Abstract: On the basis of the phase-differential locating equation obtained by the correspondence relationship between radial distance and phase, applying the trigonometric equation obtained by cosine law, the set of linear equation solving the target position can be obtained only by simple mathematical manipulation. Now, the location parameter of target can be solved and the accurate DF formula can be derived for the phase interference array with double baseline in one-di- mensional space. The verification for accurate solution and analysis for measuring error can be worked out by using the equivalence between path length difference and phase difference. But also, the analysis process is not related to the integer of wavelength and phase-differential measurement of discriminator. The study in this paper provides a theoretical basis for the correction of the measurement accuracy to the existing approximate solution obtained by the assumption of parallel incident wave.

机载平台相对角速度的相移检测法
Detection Method of Relative Angular Velocity by Measuring Phase-Shift on Airborne Platform
 [PDF]


Journal of Antennas (JA) , 2012, DOI: 10.12677/JA.2012.12004
Abstract:

如对基本测向公式进行微分变形,则即可得到基于频差检测的角速度计算公式。进一步引用相差与频差之间的函数关系,即可将频差检测等效转化为相差检测。模拟计算验证了本文所导出的仅基于相差检测的角速度计算公式的正确性。误差分析则表明,在综合考虑了相差和速度的测量误差之后,具有实时测量性能的新方法可实现小于1 mrad/s的测量精度。

After making the differential transformation for direction finding based on phase interferometry, the formula of angular velocity can be obtained by measuring frequency difference. Further, the measurement for frequency differ- ence can be transformed into phase difference measurement as soon as the function relationship between frequency shift and phase shift is introduced. The analog calculation validates that derived formula only based on phase difference measurement is correctness. The error analysis shows that the new method which has the performance of real-time measurement can achieve the measurement accuracy less than 1 mrad/s after synchronously calculating the measurement error of phase difference and airborne platform flight speed.

 

虚拟基线的相位跳变及校正
Phase Jump of Virtual Baseline as Well as Correction
 [PDF]


Journal of Antennas (JA) , 2013, DOI: 10.12677/JA.2013.21002
Abstract:

分析发现,在对相邻两基线采用异侧比值相减方式构造虚拟短基线时,在部分的到达角方向上,波长整周数的差值将不为零,而是存有跳变。并且,在利用虚拟短基线的无模糊测向结果求解长基线的相位模糊值的过程中同样存有相位跳变问题。本文的分析表明,通过对到达角的正弦值进行判别即可实现校正,且修正因子即为两基线差值的比例因子。最后通过应用精确测向公式从理论上说明,若不考虑相差测量误差,则通过校正之后,采用一维双基线阵列即能获得较高的测向准确性。

While the virtual short baseline is constructed by using the ratio subtraction in contrary terminal for adjacent two baselines, the differential of wavelength integer is not to zero in some arrival angle direction and but there is a jump. At the same time, there is also jump problem while using the DF result of virtual short baseline without phase ambiguity solves the phase ambiguity valuation of long baseline. The analysis in this paper shows that the emendation can be realized by distinguishing for the sinusoidal valuation of arrival angle. Also, the modifying factor is namely the proportional factor of differential between two baselines. Finally, applying the accurate DF formula explains in theory that higher accuracy of DF can be obtained by using two baselines arrays after revising without considering the phase error.

 



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