基于CIELab色空间法分析光质对葡萄酒颜色的影响

光辐射能够导致葡萄酒颜色变暗、酒体衰老。为延长葡萄酒的货架期,采用蓝光、红光、绿光、棕光和白光分别对葡萄酒进行辐照处理,研究不同光照对葡萄酒的影响。结果发现,蓝光处理后葡萄酒的L^(*)和a^(*)分别下降了20.53和1.282,而b^(*)增加了9.9,表明蓝光对葡萄酒颜色损伤较大。棕光和绿光处理组葡萄酒辐照7 d后,亮度与对照组无显著差异,a^(*)略有增加,红色色调有增加的趋势。损伤最大的是白光处理组,葡萄酒L^(*)和a^(*)分别下降了19.86和6.33,而b^(*)值增加了12.9,辐照7 d后,葡萄酒颜色变暗,呈现棕色色调,出现老化特征。总之,蓝光、白光处理对葡萄酒的颜色影响较大,棕光和绿光影响较小,因此葡萄酒建议使用棕色或绿色玻璃瓶进行贮藏。

色空间法葡萄酒颜色分析仪的设计

颜色对于葡萄酒感官质量起着重要的作用,如何品鉴葡萄酒的好坏呢?最直观当属观色,单从酒的颜色来讲就蕴含着很多重要信息,最重要的一点是我们可以通过颜色对比即可对葡萄酒进行品鉴、分级。在葡萄酒颜色分析仪诞生以前对于葡萄酒的鉴定只是通过人眼观察,但是在相近色的判断上,人的主观差异所导致的误差也是不容忽视的,"目视+语言描述"的方法有相当大的随机误差。为了改变传统肉眼葡萄酒色度的判定方法,我们根据行业标准CIE 1976(L*a*b*)色空间法,用葡萄酒颜色分析仪来对葡萄酒的颜色进行分析检测,同时也可以判断出同一批样品的葡萄酒色差是否在合格范围内。

色空间法结合化学计量学研究麦麸含水量、粒径及其用量对麸炒山药外观颜色的影响

目的以色空间法结合化学计量学研究麦麸对麸炒山药外观颜色的影响,为中药炮制辅料麦麸质量标准的制定和麸炒炮制工艺的优选提供依据。方法以不同含水量(ω)、不同粒径(Φ)的麦麸为辅料以及加入不同用量(n)的麦麸,分别制备麸炒山药。采用色差仪测定麸炒山药外观色度值L^(*)、a^(*)、b^(*)及总色度值Eab^(*)[L^(*)为亮度,a^(*)为红绿色度值,b^(*)为黄蓝色度值,Eab^(*)=(L^(*)2+a^(*)2+b^(*)2)1/2],采用SIMCA 14.1和SPSS statistics 26对麸炒山药外观色度值进行数据分析。结果麦麸含水量主要影响麸炒山药外观色度值a^(*),含水量越大,a^(*)值越小;麦麸粒径主要影响麸炒山药外观色度值L^(*),粒径越细,L^(*)值越分散;麦麸用量则主要影响麸炒山药外观色度值a^(*)、b^(*),每100 g山药用麦麸5~20 g,麦麸用量越大,a^(*)、b^(*)值越大。合适规格麦麸炮制的麸炒山药外观色度值及总色度值范围分别为81.09≤Eab^(*)<90.12。基于色度值的麦麸规格参数非标准化典则判别函数式分别为ω=0.688 L^(*)+1.264 a^(*)-0.872 b^(*)-18.113,Φ=0.058 L^(*)+0.049 a^(*)-3.696,n=0.346 L^(*)+0.867 a^(*)-24.666。结论麦麸含水量<25%,粒径10~50目,每100 g山药饮片用麦麸10~15 g,炮制出的麸炒山药饮片符合《中国药典》2020年版性状要求。过于潮湿、粒径过细及麦麸用量过大或过小均难以满足麸炒山药的外观颜色要求。

An improved Vibe algorithm for illumination mutations

The visual background extractor(Vibe)algorithm can lead to a large area of false detection in the extracted foreground target when the illumination is mutated.An improved Vibe method based on the YCbCr color space and improved three-frame difference is proposed in this paper.The algorithm detects the illumination mutation frames accurately based on the difference between the luminance components of two frames adjacent to a video frame.If there exists a foreground moving target in the previous frame of the mutated frame,three-frame difference method is utilized;otherwise,Vibe method using current frame is used to initialize background.Improved three-frame differential method based on the difference in brightness between two frames of the video changes the size of the threshold adaptively to reduce the interference of noise on the foreground extraction.Experiment results show that the improved Vibe algorithm can not only suppress the“ghost”phenomenon effectively but also improve the accuracy and completeness of target detection,as well as reduce error rate of detection when the illumination is mutated.

Segmentation of Somatic Cells in Goat Milk Using Color Space CIELAB

Somatic cell counts （SCCs） levels indicate the occurrence of infections in goat udders and are related to the productivity of goat milk, cheese and yoghurt. This work presents a segmentation method for counting somatic cells in goat milk images, intending to detect an infection known as mastiffs, which is the major cause of loss in dairy farming. The image segmentation procedure is devised by using the lab color space and the watershed transform. A large number of samples under variable preparation conditions are treated with the proposed method. A comparison between manual and the proposed technique is presented. Promising results indicates that video-microscopy systems may be employed to develop automated SCC for goat milk.

Development of HEP-XXMF Series Hall Thrusters in BICE

Hall thruster is a type of electric propulsion thruster which is often regarded as a moderate specific im- pulse space propulsion technology and is used primarily for station keeping and orbit maintenance tasks. Magnetic field is the most important aspect in Hall thruster＇s design. Each time the performance improvement of Hall thrusters is accompanied with the regeneration of magnetic field design. Now, all the maior space nations treat the magnetic field design as the key technology for Hall thrusters, and many Hall thrusters have emerged in recent years, for example, BPT-4000 and NASA- 173M. In China, based on magnetic focus technology, the Beijing Institute of Control Engineer- ing （BICE） has been developing Hall thrusters ranged from hundreds of watts to 5 kilowatts, including the IS00 W HEP- 100MF and the 5 kW HEP- 140blF Hall thrusters. This paper briefly reviews the development of the HEP-XXMF series Hall thruster. The principle of the Hall thruster, the design methods and the current status of HEP-100MF and HEP- 140MF are discussed in the paper.

Functional safety verification and performance measurement of train-train communication link

The short-range wireless communication technology has advanced considerably and provides the feasibility of train-train(T2T)communication link in the communication-based train control system.The introduction of the T2T link would reduce the headway and improve operational efficiency.Formal methods are system design techniques that use rigorously specified mathematical models to ensure all behaviors work as expected.And it is exactly the functional safety verification needed.Therefore,to deal with the functional safety verification of the T2T link,an untimed colored petri net model is first constructed.Secondly,the verification process is performed.Conclusions can be drawn from the state space report and the computation tree logic queries.Lastly,the model is parameterized,and then data log files are obtained for further performance measurement.Results show that the proposed criteria are satisfied and there are no defects in the basic design requirements.The transmission delay has considered the reconnection,transmission errors and the interruption.The probability of the delay lower than 150 ms accounts for 98.106%,which meets the specification and the previous field test.

Suitability of Steric Mass-action Model for Ion-exchange Equilibrium of Micromolecule

The steric mass-action (SMA) model has been widely reported in the literature for ion-exchange and metal-affinity interaction adsorption equilibrium of biomacromolecules. In this paper, the usefulness of SMA model is analyzed for describing micromolecule ion-exchange equilibrium onto cation exchangers, CM Sephadex C-25 and Streamline SP. Batch adsorption experiments with ephedrine hydrochloride as a model adsorbate are carried out to determine the model parameters, that is, steric factor, characteristic charge and equilibrium constant. The result shows that the SMA model parameters of micromolecule cannot be obtained using the nonlinear least-square fitting method as protein's due to the remarkable difference between the molecular mass and dimension of micromolecule and protein. It is considered that the small size of the adsorbates dealt with in this study justifies the neglect of steric hindrances arising from adsorbate bulkiness. Thus, the three-parameter SMA model is reduced to two-parameter one (i.e., steric factor is equal to zero) for describing micromolecule ion-exchange equilibrium. It is found that the equilibrium constant for CM Sephadex C-25 increases with increasing ionic strength, while the equilibrium constant for Streamline SP shows an opposite trend. This is probably due to the remarkable difference between the physicalpro perties of the two adsorbents. Then, the relationship between the equilibrium constant and ionic strength is described by an expression. The computer simulations show that, the theoretical model with the correlation is promising in the prediction of micromolecule adsorption decrease with increasing ionic strength in a wide range of salt concentration.

New Extended Jacobi Elliptic Function Rational Expansion Method and Its Application

In this paper, an extended Jacobi elliptic function rational expansion method is proposed for constructing new forms of exact Jacobi elliptic function solutions to nonlinear partial differential equations by means of making a more general transformation. For illustration, we apply the method to the （2＋1）-dimensional dispersive long wave equation and successfully obtain many new doubly periodic solutions, which degenerate as soliton solutions when the modulus m approximates 1. The method can also be applied to other nonlinear partial differential equations.

A Novel Approach for Unsupervised Segmentation of Homogeneous Regions in Gray-scale Images

An improved approach for JSEG is presented for unsupervised segmentation of homogeneous regions in gray-scale images. Instead of intensity quantization, an automatic classification method based on scale space-based clustering is used for nonparametric clustering of image data set. Then EM algorithm with classification achieved by space-based classification scheme as initial data used to achieve Gaussian mixture modelling of image data set that is utilized for the calculation of soft J value. Original region growing algorithm is then used to segment the image based on the multiscale soft J-images. Experiments show that the new method can overcome the limitations of JSEG successfully.

Retinex based low-light image enhancement using guided filtering and variational framework

A new image enhancement algorithm based on Retinex theory is proposed to solve the problem of bad visual effect of an image in low-light conditions. First, an image is converted from the RGB color space to the HSV color space to get the V channel. Next, the illuminations are respectively estimated by the guided filtering and the variational framework on the V channel and combined into a new illumination by average gradient. The new reflectance is calculated using V channel and the new illumination. Then a new V channel obtained by multiplying the new illumination and reflectance is processed with contrast limited adaptive histogram equalization(CLAHE). Finally, the new image in HSV space is converted back to RGB space to obtain the enhanced image. Experimental results show that the proposed method has better subjective quality and objective quality than existing methods.

Pore scale simulation of liquid and gas two-phase flow based on digital core technology

Two-phase flow in two digital cores is simulated by the color-gradient lattice Boltzmann method.This model can be applied totwo-phase flow with high-density ratio(on order of 1000).The first digital core is an artificial sandstone core,and itsthree-dimensional gray model is obtained by Micro-CT scanning.The gray scale images are segmented into discrete phases(solid particles and pore space) by the Otsu algorithm.The second one is a digital core of shale,which is reconstructed usingMarkov Chain Monte Carlo method with segmented SEM scanning image as input.The wettability of solid wall and relativepermeability of a cylindrical tube are simulated to verify the model.In the simulations of liquid and gas two phase flow in digital cores,density ratios of 100,200,500 and 1000 between liquid and gas are chosen.Based on the gas distribution in the digital core at different times,it is found that the fingering phenomenon is more salient at high density ratio.With the density ratioincreasing,the displacement efficiency decreases.Besides,due to numerous small pores in the shale,the displacement efficiency is over 20% less than that in the artificial sandstone and the difference is even about 30% when density ratio is greaterthan 500.As the density ratio increases,the gas saturation decreases in big pores,and even reaches zero in some small pores orbig pores with small throats.Residual liquid mainly distributes in the small pores and the edge of big pores due to the wettability of liquid.Liquid recovery can be enhanced effectively by decreasing its viscosity.

Support Vector Regression Based Color Image Restoration in YUV Color Space

A support vector regression(SVR) based color image restoration algorithm is proposed.The test color images are firstly mapped into the YUV color space,and then SVR is applied to build up a theoretical model between the degraded images and the original one.Performance comparisons of the proposed algorithm versus traditional filtering algorithms are given.Experimental results show that the proposed algorithm has better performance than traditional filtering algorithms and has less computation time than iterative blind deconvolution algorithm.

The Current Status, Problems and Prospects of Researches on the Carrying Capacities of Ecological Environment in China

Determining the carrying capacity of ecological resources is the key to finding contradictions between human activities and the environment,as well as the links between economic growth,environmental protection and social development.In recent years,the carrying capacity of the ecological environment has been extensively studied at home and abroad.Through extensive literature research and analysis,this paper discusses the current status and main problems of recent research on the carrying capacity of the ecological environment in China.For example,two of the main problems are that:1)the concepts and connotations are not clear enough,and 2)the research content is not systematic enough.This is followed by a summary of the evaluation index system and main calculation methods.Finally,according to the research status and development trends at home and abroad,the possible direction for the development of this research field in the future is proposed.