输电线非线性振动问题的同伦映射近似解

研究了一类输电线非线性振动的动力学模.利用同伦映射方法,得到了该模型的任意次精度的近似解. 关键词： 输电线 非线性振动 同伦映射 近似解     

一类相对转动非线性动力学模型的近似解

研究了一类具有非线性阻尼力和强迫周期力项的相对转动非线性动力学模型. 首先构造一个同伦映射, 其次决定方程的初始近似, 最后通过同伦映射方法得到了对应模型的任意次近似解. 关键词： 相对转动 非线性动力系统 近似解     

一类扰动非线性发展方程的类孤子同伦近似解析解

采用一个简单而有效的技巧,研究了一类扰动非线性发展方程.首先,引入一个相应典型方程的孤子近似解.然后,利用同伦映射方法得到了原扰动非线性发展方程的近似解. 关键词： 孤子 扰动发展方程 同伦映射     

薛定谔扰动耦合系统孤波的行波近似解法

研究了一类薛定谔非线性耦合系统.利用精确解与近似解相关联的特殊技巧,首先讨论了对应的无扰动耦合系统,利用投射法得到了精确的孤波解.再利用泛函映射方法得到了薛定谔非线性扰动耦合系统的行波近似解.     

广义Boussinesq方程的同伦映射近似解

研究了一个广义非线性Boussinesq方程. 利用同伦映射方法,首先构造了相应的同伦变换;其次选取了适当的初始近似;然后用同伦映射方法得到了孤立子波近似解;最后得到了微扰渐近表示式. 关键词： Boussinesq方程 非线性 孤立子 近似方法     

强非线性发展方程孤波同伦解法

研究了一个强非线性发展方程. 利用同伦映射方法，首先构造了相应的同伦变换；其次选取了适当的初始近似；再用迭代方法得到了孤波的任意次精度的近似解.     

扰动KdV方程孤子的同伦映射解

利用同伦映射方法研究了一类非线性KdV(Korteweg de Vries)方程. 首先引入一个同伦变换,使相应的方程求孤子解问题转化为映射变换问题.然后利用映射特性得到了原方程孤子的近似解. 关键词： 孤子 扰动 同伦映射     

一类广义非线性扰动色散方程孤立波的近似解

采用了一个简单而有效的技巧,研究了一类非线性扰动色散方程.首先引入求解相应典型方程的孤立波解.然后利用同伦映射方法得到了原非线性扰动色散方程奇异孤立波的近似解.     

一类非线性扰动Nizhnik-Novikov-Veselov系统的孤立波近似解析解

采用了一个简单而有效的技巧,研究了一类非线性扰动Nizhnik-Novikov-Veselov系统.首先引入一个相应典型系统的孤立波解.然后利用同伦映射方法得到了原非线性扰动Nizhnik-Novikov-Veselov系统的近似解析解.     

非线性扰动时滞长波系统孤波近似解

本文是讨论一类时滞非线性扰动长波系统的孤波解.首先,引入非扰动的典型长波方程的精确解.然后,用同伦映射和改进的技巧构造了非线性扰动时滞长波系统孤波行波解的近似展开式.     

A system for the remote spectroscopy in the visible and infrared regions

Results of the design and development of a system for remote sensing of the state and evaluation of the parameters of the natural environment and objects are presented. The devices developed are based on a generalized structural model of measuring system for acquisition of data on spectral, energy, polarization, angular, and spatial characteristics of the optical radiation field of the object under investigation. A. N. Sevchenko Scientific Research Institute for Applied Physical Problems at the Belarusian State University, 7, Kurchatov St., Minsk, 220064, Belarus. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 6, pp. 827–833, November–December, 1997.     

颗粒度对不同煤种可见光-近红外光谱的影响

煤炭是我国最主要的能源,在开采、运输、洗选加工、精煤储运等过程中都需要及时了解煤的成分、含量以及混矸程度,以便掌握和监控煤炭质量。目前,基于可见光-近红外反射光谱的煤炭原位测试技术已经成为一个研究热点。颗粒度是影响光谱特征的重要因素,开展颗粒度对不同煤种反射光谱特征的影响研究,对于深刻认识煤的光谱特征,进而提高煤光谱识别精度具有重要意义。为此,选取我国主要煤炭富集区（包括内蒙古乌海、新疆哈密、山西阳泉）的褐煤、烟煤、无烟煤为研究对象,利用SVC HR-1024光谱仪对不同颗粒度煤样的可见光-近红外光谱进行测试,分析了颗粒度对煤样光谱反射率的影响规律,以及颗粒度对于不同煤种光谱影响的差异。在此基础上,对实验现象背后的物理机理进行了分析讨论。研究表明,变质程度不同的煤反射光谱特征基本相似,即在可见光波段反射率较低且随波长增加出现缓慢下降趋势,在近红外波段快速上升。当煤样颗粒度>0.10 mm时,颗粒度大小对光谱特征的影响较小,煤样反射光谱特征随颗粒度变化规律不明显;当颗粒度<0.10 mm时,颗粒度对煤样的光谱影响增大,且影响主要体现在近红外波段的反射率光谱曲线的斜率大小,颗粒度越小,光谱反射率曲线斜率越大。0.10 mm颗粒度可作为颗粒度对煤的光谱特征影响的敏感界限。不同煤种可见光-近红外光谱曲线受颗粒度的影响程度不同,褐煤的影响最大,烟煤次之,无烟煤影响最小。实验表明,利用反射光谱进行煤质分析和煤种识别时需要考虑颗粒度的影响,同时,选择颗粒度小于0.10 mm的粉末状样品效果要好于大颗粒或块状样品。     

Laser absorption and fluorescence diagnostics of a plasma

Diagnostics of a near-surface laser plasma, the plasma of a strong-current pulse gaseous discharge in inert gases, nitrogen, and carbon dioxide under conditions of intense evaporation of the wall of the discharge chamber, the plasma of a discharge with a hollow cathode, and the active medium of an excimer laser was conducted by methods of intracavity laser spectroscopy and laser-induced fluorescence. The dynamic fields and absolute concentrations of atoms, ions, molecules and electrons, the plasma temperature, and the velocities of flows of particles were measured. The quantitative determination of the density of particles in the erosion laser flame prior to breakdown and the phenomena associated with the formation of molecules in the laser plasma received primary consideration. To whom correspondence should be addressd. Instite of Molecular and Atomic Physics of the Academy of Sciences of Belarus, 70, F. Skorina Ave., Minsk, 220072, Belarus. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 3, pp. 281–290, May–June, 1997.     

Hardware and software for the automating atomic-absorption spectrometers AAS, S115, and saturn

We describe a modified GELIOS System intended to automate the atomic-absorption spectrometers AAS, S115, SATURN, and Perkin-Elmer 503. Software is prepared in the visual environment of programming DELFI-3 and functions under the control of Windows 95. A distinguishing feature of the GELIOS System is simultaneous search for the peak and area of the absorption signal, correction of the errors of measurements, automatic digital filtration of data, control of the time of operation of hollow-cathode lamps, measurement of spectra and the statistical resource of the service life of hollow-cathode lamps, use of different methods to construct a calibrating graph, the possibility of memorizing the data of the analysis in an archived file, and a formation of the report for printing. The system contains an electrovic data directory on atomicabsorption analysis in five volumes for 67 elements of the Mendeleev system. To whom correspondence should be addressed. “University” Science and Production Center, 4, F. Skorina Ave., Minsk, 220050, Belarus. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 66, No. 5, pp. 734–737, September–October, 1999.     

Effect of the mode composition of laser radiation on the intracavity formation of periodic surface structures

We investigated the effect of the mode composition (longitudinal and transverse modes) of laser radiation on the basic parameters of the stroke pattern formed on a treated surface placed inside a laser cavity. We found that the contrast of the stroke pattern formed by a laser beam with a complex set of longitudinal modes depends, in the first place, on the width of the laser radiation spectrum and the laser cavity length and is virtually independent of the angle of rotation of the beam. In the region of small rotation angles the broadening of strokes caused by the effect of transverse modes becomes predominant. B. I. Stepanov Institute of Physics, Academy of Sciences of Belarus, 70, F. Skorina Ave., Minsk, 220072, Belarus. Translated from Zhurnal Prikaladnoi Spektroskopii, Vol. 64, No. 1, pp. 50–54, January–February, 1997.     

基于光谱和成像技术的果蔬质量检测研究进展

为保证食品安全和消费者健康,无损检测技术广泛应用于果蔬质量检测中。光谱和图像技术可分别获取果蔬的内部和外部信息,成为质量检测的有效工具。为跟踪国内外研究进展并分析研究现况,从果蔬外部品质(尺寸、形状、表面缺陷、颜色、纹理等)、内部品质(内部缺陷、可溶性固形物、可滴定酸、水分、类胡萝卜素等单一品质及综合品质)、成熟度、货架期/贮藏期、产品溯源、生长监测、安全(农药残留、病虫和细菌侵染、转基因产品等)检测及光学系统设计等方面综述了光谱和成像技术的应用,分析了存在的图谱库不完善、解混处理算法复杂、高精度和便携式的光学系统开发力度不够、校正模型的影响因素复杂等问题。然后,归纳了发展趋势,指出了各组分可视化分析及交互作用机理解析、光与果蔬组织的交互作用机理分析和光学特性参数反演等光学特性分析、科学合理的综合评价体系的建立、新算法的应用和多种算法的联合使用、不同算法的可靠性和稳定性的提高、稳定和普适模型的建立、低成本和便携式等光学分析仪器的商品化开发和商业化应用等成为进一步探索的方向,为基于光谱和成像技术的果蔬质量检测发展提供了参考。     

Rotation of the light polarization plane by an ensemble of oriented linear associates: Model representations

In an “oriented gas” model expressions are obtained for the angle of nongyrotropic rotation of the polarization plane (NRPP) of transmitted light by an ensemble of oriented associates consisting of nongyrotropic molecules. The cluster character of the nongyrotropic rotation of the polarization plane and the dependence of its angle on the incident light polarization vector azimuth are noted, which distinguish linear and circular polarization effects. Measurement of linear dichroism by the angle of nongyrotropic rotation of the polarization plane with the use of commercial spectropolarimeters is theoretically justified. Institute of Molecular and Atomic Physics, National Academy of Sciences of Belarus, 70, F. Skorina Ave., Minsk, 220072 Belarus. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 65, No. 1, pp. 95–101, January–February, 1998.     

基于NIR和SOM-RBF网络的兰州百合关键营养物质定量分析方法

为了实现兰州百合关键营养物质蛋白质和多糖的快速无损检测,在12 000～4 000 cm^-1光谱范围内采集了59份兰州百合粉的近红外光谱(NIRS)。首先运用SG、 Normalize、 SNV、 MSC、 Detrend、 OSC、 SG+1D、 SG+Normalize、 SG+SNV和SG+Detrend十种预处理方法对原始光谱数据进行处理,确定蛋白质的最佳预处理方法为SG+Detrend、多糖的最佳预处理方法为Detrend;然后运用CARS、 SPA和PCA三种算法对预处理的光谱数据进行特征波长筛选,确定蛋白质和多糖的最佳特征波长提取方法均为SPA算法;最后采用PLSR法建立了兰州百合关键营养物质蛋白质和多糖含量的预测模型,结果显示,经过SG+Detrend＿SPA处理所建立的蛋白质PLSR模型中,预测集相关系数R_p为0.810 6,预测集均方根误差RMSEP为1.195 3;经过Detrend＿SPA处理所建立的多糖PLSR模型中,预测集相关系数R_p为0.810 9,预测集均方根误差RMSEP为2.0946。...     

基于宽带扫频的导弹RCS测量与分析

针对导弹的典型几何外形结构,基于高频散射机理对其散射特性进行了初步分析,包括散射源分布及其散射类型、各散射源散射特性随导弹姿态的变化趋势等。接着,利用宽带扫频RCS测量系统对导弹L、X波段RCS和X波段一维距离像进行了测量,得到了导弹在不同技术条件下的RCS曲线和一维距离像。最后,对测量结果进行了初步分析。测量结果表明：导弹头锥仓与进气道腔体存在较大散射,尤其是进气道壁与弹体之间连接缝隙的散射较为突出;导弹在X波段下的RCS较L波段小,且受姿态变化的影响更为敏感;另外,导弹RCS峰值点并未出现在迎头向,而是偏离迎头向一定角度,尤以X波段下最为明显,偏离角度达20°左右。测量结果为导弹在试验中的应用,包括试验设计、试验结果分析与评估、等效推论等提供了重要的技术依据。     

The width of the rotational contour of vibrational and vibronic bands of complex molecules in the gas phase as a temperature indicator

From the independence of the contour of spectral density of the rotational (orientation) correlation function of a rigid molecular top of arbitrary symmetry on temperature in the frequency scale based on the reduced time of rotational orientation relaxation and from the near independence of the rotational contour of vibrational and vibronic absorption bands of dipole transitions in the same coordinates in a model of “regular diffusion” of the transition oscillator with a classically rotating rigid molecular top, it is suggested that it is possible to use the halfwidth of the contour for estimation of temperatures. Data are presented on the halfwidth of 48 contours of bands of A, B, and C types at this frequency for 12 compounds for a temperature range of from units to 500 degrees of absolute temperature measured experimentally and (for low temperatures) calculated by the quantum theory. Institute of Molecular and Atomic Physics, Academy of Sciences of Belarus, 70, F. Skorina Ave., Minsk, 220072, Belarus. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 3, pp. 312–317, May–June, 1997.