In this article, we extend the definition of uniformly starlike functions and uniformly convex functions on the unit disk to the unit ball in Cn, give the discriminant criterions for them, and get some inequalities for them.

In this article, we extend the definition of uniformly starlike functions and uni-formly convex functions on the unit disk to the unit ball in Cn, give the discriminant criterions for them, and get some inequalities for them.

基于图像颜色、纹理和形状单一特征的特征提取和匹配的方法很多,各有优缺点,因此,本文提出了将图像中心区域的uniform模式的LBP纹理与环形分块彩色边缘相结合的图像检索算法。常用的形状检索算法只能对连续封闭曲线才有好的检索效果,而对自然彩色图像检索效果较差,而本文将图像分成几个环形分块,对每一环形分块内的图像提取彩色边缘并形成颜色直方图用于图像形状描述。纹理采用uniform模式的LBP描述,最后采用加权法融合形状特征和纹理特征。根据实验比较,该算法能较大提高大多数类别图像检索的查准率。

Feature extraction and matching method based on single feature such as image color, texture and shape are many, each has advantage but also has some shortcomings, thus puts forward the uniform model of the central region of the image of LBP texture combined with a circular block color edge of image retrieval algorithm. The shape of the commonly used retrieval algorithm can only has a good retrieval effect of continuous closed curve, and the natural color image retrieval effect is poorer. This article sepa-rates the image into several annular blocks, and then uses form of color histogram to image the shape description for each ring image edge extraction of color, and uses the uniform model of LBP to describe texture. Finally, shape features and texture features are in-corporated by using weighted method. According to the experimental comparison, our method can improve greatly and most of the cat-egories of the image retrieval precision.

The NaYF4:Yb,Er nanocrystals were synthesized via the thermal decomposition of metal oleate precursors. The nanocrystals in hexagonal structure were highly uniform and in size of 25 nm. The bright upconversion luminescence was observed under the excitation of 980 nm laser and the upconversion emission spectra were investigated at different pump powers. The emission intensity ratio of red light to green light linearly increased with pump power increasing. This result indicated that there existed a large threshold power of saturation pump for the first excitation state in NaYF4:Yb,Er nanocrystals comparing to that in bulk material.

The NaYF4:Yb,Er nanocrystals were synthesized via the thermal decomposition of metal oleate precursors. The nanocrys-tals in hexagonal structure were highly uniform and in size of 25 nm. The bright upconversion luminescence was observed under the excitation of 980 nm laser and the upconversion emission spectra were investigated at different pump powers. The emission intensity ratio of red light to green light linearly increased with pump power increasing. This result indicated that there existed a large threshold power of saturation pump for the first excitation state in NaYF4:Yb,Er nanocrystals comparing to that in bulk material.

为了减轻噪声干扰,提取更为丰富的人脸鉴别特征,提出了局部三值微分模式算子。通过判断近邻像素灰度值是否在某个范围内对当前像素的局部微分模式从二值扩展到三值,然后将扩展后编码的Uniform模式的空间直方图依次相连形成人脸的特征向量,采用卡方统计算样本相似度并进行分类。在ORL、Yale和CAS-PEAL-R1人脸数据库上的实验结果表明,提出的算法的识别性能优于局部二值模式和局部微分模式。、

In order to reduce noise and extract richer discriminant feature, the local ternary local derivative pattern operator was proposed. By determining whether the adjacent pixel gray values within a certain range, the local derivative pattern of current pixel was extended from binary to ternary, and the face feature vector was formed by sequentially connecting the uniform pattern of the space histogram of the encode. The chi-square statistic was used to calculate the sample similarity of face feature vector. The experimental results on ORL, Yale and CAS -PEAL -R1 face database show that the recognition performance of the proposed algorithm was superior to local binary pattern and local derivative pattern.

Hexagonal-phase NaYF4:Yb3+,Er3+ upconversion nanoparticles(UCNPs) with a uniform size distribution were synthesized using rare-earth acetates as precursors. The effects of reaction temperature and time on the phase transition process of the UCNPs were systematically studied. Based on the evolution of particle morphology and phase with temperature and time, it could be concluded that the transition from cubic phase to hexagonal phase for NaYF4:Yb3+,Er3+ UCNPs was consistent with a dissolution/recrystallization process. In addition, the shape and size of the UCNPs could be controlled by adjusting the solvent ratio and the precursor ratio, respectively.

Hexagonal-phase NaYF4:Yb3+,Er3+upconversion nanoparticles (UCNPs) with a uniform size distribution were synthesized using rare-earth acetates as precursors. The effects of reaction temperature and time on the phase transition process of the UCNPs were systematically studied. Based on the evolution of particle morphology and phase with temperature and time, it could be concluded that the transition from cubic phase to hexagonal phase for NaYF4:Yb3+,Er3+UCNPs was consistent with a dissolution/recrystallization process. In addition, the shape and size of the UCNPs could be controlled by adjusting the solvent ratio and the precursor ratio, respectively.