Short-wave near-infrared spectroscopy analysis of major compounds in milk powder and wavelength assignment

In this study, short-wave near-infrared (NIR) spectroscopy at 800–1050 nm region was investigated for the analysis of main compounds in milk powder. Through quantitative analysis, the feasibility is further demonstrated for the simultaneous measurement of fat, proteins and carbohydrate in milk powder. Two models, partial least-squares and least-squares support vector machine, were compared and utilized for regression coefficients and loading weights. The affect of standard normal variate spectral pretreatment to model performance was evaluated. Based on the resulted coefficients and loading weights, interesting wavelength regions of nutrition in milk powder are screened and the assignment of all specific wavelengths is firstly proposed in the details associated with chemical base. Instead of the whole short-wave NIR spectral data, these assigned wavelengths which can be reliably exploited were used for the content determination. Compared with other spectroscopy technique, assigned short-wave NIR spectral wavelengths did a good work. Determination coefficients for prediction are 0.981, 0.984, and 0.982, respectively for three components. The proposed wavelength assignment in the short-wave NIR region could be used for the component contents determination of milk powder, and could be as a guidance to interpret the spectra of milk powder.     

坚硬岩石在强冲击荷载作用近区的性状研究

根据坚硬岩石的性质,利用力学模型分析了在冲击荷载作用下的岩石破坏过程,经由弹性状态向内摩擦状态的转变,最终达到流体力学状态。通过对内摩擦状态的分析,认为在强冲击荷载区域的变形近似为一维变形状态。冲击荷载作用在岩石中产生的应力波可以看作类似于冲击波的短波,在波阵面附近的某个狭窄区域内将发生参数的急剧变化。根据近区变形状态与质量守恒导出了侵彻近区的速度场表达式。根据短波的研究,给出了近区应力波的衰减规律。     

Darboux transformations for a matrix long-wave–short-wave equation and higher-order rational rogue-wave solutions

A new matrix long-wave–short-wave equation is proposed with the of help of the zero-curvature equation. Based on the gauge transformation between Lax pairs, both onefold and multifold classical Darboux transformations are constructed for the matrix long-wave–short-wave equation. Resorting to the classical Darboux transformation, a multifold generalized Darboux transformation of the matrix long-wave–short-wave equation is derived by utilizing the limit technique, from which rogue wave solutions, in particular, can be obtained by employing the generalized Darboux transformation. As applications, we obtain rogue-wave solutions of the long-wave–short-wave equation and some explicit solutions of the three-component long-wave–short-wave model, including soliton solutions, breather solutions, the first-order and higher-order rogue-wave solutions, and others by using the generalized Darboux transformation.     

On the exact solutions to the long–short-wave interaction system

The complete discrimination system for polynomial method is applied to the long-short-wave interaction system to obtain the classifications of single traveling wave solutions. Compared with the solutions given by the （G~/G）-expansion method, we gain some new solutions.     

基于GPS和短波的高精度时钟系统研究与设计

介绍了全球定位系统GPS、短波授时技术;在对高稳恒温晶振及其频率特性进行分析的基础上,设计了一种基于GPS卫星、短波无线电授时的高精度时钟系统;系统通过利用GPS接收处理模块、短波授时接收模块得到的秒脉冲信号、时间信息,经过信号检测,时延修正处理、性能优选,脉冲数量统计、脉冲滤波与卡尔曼算法处理、PWM脉冲调压控制,实现对高稳恒温晶振频率的校准,获得一个短期及长期频率准确度都比较优良的时间频率标准,同时利用校频后恒温晶振分频出的1 pps信号对RTC时间芯片进行校准,对外输出高精度时间信息;对恒温晶振校频系统的基本工作原理及关键技术进行了详细说明,试验结果表明,在时间不长于1 h内,频率准确度优于0.9*10-9;该系统实用方便,达到了将恒温晶振校准到较高指标的目的。     

Variable separation solutions and new solitary wave structures to the (1+1)-dimensional equations of long-wave－short-wave resonant interaction

A variable separation approach is proposed and extended to the (1+1)-dimensional physical system. The variable separation solutions of (1+1)-dimensional equations of long-wave－short-wave resonant interaction are obtained. Some special type of solutions such as soliton solution, non-propagating solitary wave solution, propagating solitary wave solution, oscillating solitary wave solution are found by selecting the arbitrary function appropriately.     

人工电离层洞形态调制及其对短波传播的影响

本文在电离层中性气体点源扩散近似解的基础上,给出了多源释放动力学模型.分析了释放物质、释放高度、释放模式和释放量等因素对人工电离层洞形态调制的影响,并利用电离层短波三维数字射线追踪技术,对不同调制电离层洞的电波传播效应进行了数值模拟和分析. 关键词： 化学物质释放 人工电离层洞 形态调制 电波传播效应     

红外滤光片低温光谱特性研究

低温光谱是红外滤光片一项重要的考核参数，采用傅里叶光谱仪测试了红外滤光片在安装滤光片架前后的常温和85K低温光谱，同时利用有限元分析方法模拟了85K的红外滤光片安装滤光片支架前后的形变和应力，分析和比较了试验结果，为进一步优化红外滤光片的可靠性设计提供了参考。     

Portable Analyzer for Rapid Analysis of Total Protein, Fat and Lactose Contents in Raw Milk Measured by Non-dispersive Short-wave Near-infrared Spectrometry

A novel portable analyzer for raw milk quality control during the material purchase at dairy plants was developed, by which the percentages(mass fraction) of main components including total protein, fat, and lactose of an unhomogenized milk sample could be determinated in 1 min with the help of non-dispersive short-wave near-infrared (NDSWNIR) spectrometry in a wavelength range from 600 nm to 1100 nm and multivariate calibration. The analyzer was designed with a single-beam optical system, which comprised a temperature control module, a multi-channel narrow-band light source(16 wavelengths), a glass absorption cell with 15 mm sample thickness, a silicon photodiode detector, several compound lenses and a recorder module. A total of 80 raw milk samples were collected at a dairy farm twice a month for 4 months. The samples were scanned with a common UV-Vis-NIR spectrometer and analyzed according to China GB standard methods. The uninformative variables elimination(UVE) method was carried out on the spectrum data and the percentages of main components of all the samples to choose the peak emitting wavelength of each channel of the light source. Another 90 raw milk samples were collected from the same dairy farm thrice a month for 3 months. The samples were analyzed according to China GB standard methods and with the proposed analyzer. The percentages of the main components and the NDSWNIR absorption data of the samples were used for the construction and validation of the multivariate calibration model with partial least squares(PLS) method. The root-mean-square errors of prediction(RMSEP) of total protein, fat and lactose were 0.201, 0.172 and 0.247 and the coefficients of correlation(R) were 0.932, 0.981 and 0.933, respectively.     

基于灰度空间相关性的双谱微光图像融合方法

图像的灰度空间相关性可以反映图像的清晰度，而图像融合的主要目的之一就是改善图像的清晰度.根据微光全波图像和微光短波图像的光谱特点，在分析微光全波图像和微光短波图像的一维灰度直方图及二维灰度空间相关性图的基础上，提出了一种新型的基于灰度空间相关性的图像融合方法.该融合方法由基于标准偏差的灰度调制和灰度统计平衡两部分实现，同灰度调制融合法及谱域融合法比较，此方法能够有效地改善图像的清晰度，同时便于硬件实现.文中详细阐述了该融合方法的理论公式，并分析了其在不同场景时的实验结果. 关键词： 图像融合 微光全波图像 微光短波图像 灰度空间相关性