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1.
KH-931是以褐煤、丙烯酰胺、丙烯腈为原料制得的无荧光防塌降失水剂。本文简介了KH-931的合成条件,并对KH-931的防塌作用与降滤失作用进行了室内评定。实验结果表明,KH-931的防塌、降失水效果良好,并具有加量少、无荧光的特点。腐殖酸衍生物,降滤失剂,页岩抑制剂,多功能钻井液处理剂,荧光性,实验室研究  相似文献   
2.
利用零件的相似性原理对零件分组是派生式CAPP系统的重要内容,对零件的分组是否合理,直接影响到派生式CAPP系统能否正常运行。阐述了排序聚类分析算法在生产流程分析法中的工作原理,分析了利用该算法实现零件分组的实现过程,并用示例验证了该算法。  相似文献   
3.
随着国内动漫创作质量的提高和产业链的不断完善,动漫综合开发也带来了衍生产品及其市场的发展,形成了动漫产业全方位发展的格局。本文主要针对我国动漫衍生产品的现状、存在的问题和未来发展趋势,进行系统地阐述与分析。  相似文献   
4.
壳聚糖及其衍生物的吸附特性研究进展   总被引:6,自引:0,他引:6  
袁彦超  王培秋  陈炳稔 《辽宁化工》2002,31(7):291-294,314
综述了壳聚糖及其衍生物对重金属离子、酸和有机染料等吸附特性的研究进展。  相似文献   
5.
The rth order nonlinearity of a Boolean function is an important cryptographic criterion in analyzing the security of stream as well as block ciphers. It is also important in coding theory as it is related to the covering radius of the Reed-Muller code R(r,n). In this paper we deduce the lower bounds of the second order nonlinearities of the following two types of Boolean functions:
1.
with d=22r+2r+1 and , where n=6r.
2.
, where x,yF2t,n=2t,n?6 and i is an integer such that 1?i<t,gcd(2t-1,2i+1)=1.
For some λ, the functions of the first type are bent functions, whereas Boolean functions of the second type are all bent functions, i.e., they possess the maximum first order nonlinearity. It is demonstrated that in some cases our bounds are better than the previously obtained bounds.  相似文献   
6.
A new method of estimating per-pixel atmospheric column water vapor (ACWV) and potential differences in the reported band center wavelengths of the HyMap sensor has been developed. The new method uses variations of a second order derivative algorithm (SODA) to assess the impact of atmospheric residual features on calculated surface reflectance spectra after atmospheric compensation. The SODA method provides an alternative to the current band ratio techniques of ACWV estimation and also allows the same form of algorithm to be used for the estimation of possible band shifts. A comparison of in-situ measured surface reflectance at two field sites in Western Australia demonstrates improvement in the resulting spectra when post-flight updates are made to the reported HyMap band center wavelengths and applied during the atmospheric compensation process. The same SODA methodology was varied to estimate the ACWV on a per-pixel basis and found to significantly reduce the appearance of the underlying surface structure on the resulting ACWV images as well as improve the overall accuracy of the estimation. The ACWV estimated from the HyMap imagery at the two field sites was found to agree with in-situ atmospheric ACWV measurements to within 2% and represented a two fold increase in accuracy over a 3 band ratio Continuum Interpolated Band Ratio (CIBR) technique of ACWV estimation.  相似文献   
7.
A novel bacterial foraging technique for edge detection   总被引:2,自引:0,他引:2  
A new approach for edge detection using a combination of bacterial foraging algorithm (BFA) and probabilistic derivative technique derived from Ant Colony Systems, is presented in this paper. The foraging behavior of some species of bacteria like Escherichia coli can be hypothetically modeled as an optimization process. A group of bacteria search for nutrients in a way that maximizes the energy obtained per unit time spent during the foraging. The proposed approach aims at driving the bacteria through the edge pixels. The direction of movement of the bacteria is found using a direction probability matrix, computed using derivatives along the possible directions. Rules defining the derivatives are devised to ensure that the variation of intensity due to noise is discarded. Quantitative analysis of the feasibility of the proposed approach and its comparison with other standard edge detection operators in terms of kappa and entropy are given. The effect of initial values of parameters of BFA on the edge detection is discussed.  相似文献   
8.
Abstract

The work presents two methods for preliminary determination of analytical wavelength when a binary system is analysed by derivative spectrophotometry. “The method of disturbing effect” involves the recording of derivative spectra of a series of two-component solutions where the concentration of one component of the mixture remains unchanged, whereas the concentration of the other changes. “The method of sixteen solutions” involves the recording of derivative spectra of a series of 16 solutions, in which to four concentrations of the one component correspond four different concentrations of the other component of the mixture.  相似文献   
9.
以信息改进为目的,以微观的企业信息为研究对象,结合企业信息化实施过程中信息管理的现状与存在的主要问题,从信息来源、信息用途的视角提出了以企业基础信息和衍生信息概念为基础的信息分类方法,建立了新的企业信息流程框架模型,并针对两种不同的信息类型设计了差异化的信息质量改进提高方法。新的信息分类方法在某企业信息化实施过程中的应用结果表明,能够促进企业信息质量的改进。  相似文献   
10.
High resolution melting curve analysis (HRM) is an emerging new method for interrogating and characterizing DNA samples. It has been used as a powerful tool for gene mutation and single-nucleotide polymorphism (SNP) detection with high throughput and low cost. Commercially available HRM analysis systems are mostly proprietary and expensive. It lacks the flexibility for the end users and researchers to incorporate new analysis algorithms into the existing system. This paper presents the development of a MATLAB-based open software program for high resolution melting curve analysis. Key analysis functions, such as to obtain the first derivative curve using Savitzky–Golay filter, to identify the melt region, subtraction of background fluorescence and curve normalization, are introduced, followed by case studies of HRM analysis using the developed software program.  相似文献   
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