基于单片机的开关电源并联供电系统的设计

针对并联供电中各电源模块参数的分散性,导致输出电流的不均衡,结果分担电流多的模块热应力大,降低了系统的可靠性等问题,提出了具有均流技术的开关并联供电系统的设计.     

Secret shared multiple-image encryption based on row scanning compressive ghost imaging and phase retrieval in the Fresnel domain

A multiple-image encryption method is proposed that is based on row scanning compressive ghost imaging, (t, n) threshold secret sharing, and phase retrieval in the Fresnel domain. In the encryption process, after wavelet transform and Arnold transform of the target image, the ciphertext matrix can be first detected using a bucket detector. Based on a (t, n) threshold secret sharing algorithm, the measurement key used in the row scanning compressive ghost imaging can be decomposed and shared into two pairs of sub-keys, which are then reconstructed using two phase-only mask (POM) keys with fixed pixel values, placed in the input plane and transform plane 2 of the phase retrieval scheme, respectively; and the other POM key in the transform plane 1 can be generated and updated by the iterative encoding of each plaintext image. In each iteration, the target image acts as the input amplitude constraint in the input plane. During decryption, each plaintext image possessing all the correct keys can be successfully decrypted by measurement key regeneration, compression algorithm reconstruction, inverse wavelet transformation, and Fresnel transformation. Theoretical analysis and numerical simulations both verify the feasibility of the proposed method.     

WLAN共建共享方案探讨

主要讨论了WLAN共建共享的4种组网方案,分析了每种方案的优缺点以及应用场景,并给出了WLAN共建共享架构下的网络规划方案。     

Meromorphic functions with weighted sharing of three values

In this article we study the problem of uniqueness of meromorphic functions with weighted sharing of three values. The results in this article improve some theorems of M. Ozawa, H. Ueda, G. Brosch, H. Yi, I. Lahiri and other authors. Examples are provided to show that the conditions of our results are sharp.     

Time-series analysis of pressure fluctuations in gas–solid fluidized beds – A review

This work reviews methods for time-series analysis for characterization of the dynamics of gas–solid fluidized beds from in-bed pressure measurements for different fluidization regimes. The paper covers analysis in time domain, frequency domain, and in state space. It is a follow-up and an update of a similar review paper written a decade ago. We use the same pressure time-series as used by Johnsson et al. (2000). The paper updates the previous review and includes additional methods for time-series analysis, which have been proposed to investigate dynamics of gas–solid fluidized beds. Results and underlying assumptions of the methods are discussed.     

β-苦瓜素的结构分析与表位预测

采用佳物信息学方法、神经网络算法、量化矩阵法和隐式马尔可夫模型,分析β-苦瓜素蛋白的空间结构,预测其信号肽、B细胞抗原表位、细胞毒性T细胞表位、主要组织相容性复合物分子结合肽,对β-占瓜素蛋白序列作预测打分.得出β-苦瓜素启始部有一段22个氨基酸构成的信号肽,分布着6个B细胞表位,3个CTL表位,序列71-79的HLA...     

Improvements of a two-in-one image secret sharing scheme based on gray mixing model

Yang and Ciou recently proposed a two-in-one image secret sharing scheme (TiOISSS), which can easily preview a vague image by human eyes, but also provide a perfect reconstruction of the original image by computation. However, their scheme cannot recover the lossless image by computation as they claimed. In this paper, we resolve the problem of lossless reconstruction. In addition, we improve the visual quality of the previewed image. Also, we introduce a new definition of contrast to evaluate the visual quality of the previewed image. Compared with Yang and Ciou’s TiOISSS, our scheme can gain the lossless secret image and meantime enhance the contrast of previewed image.     

广播电视与移动通信系统频谱共享应用问题

移动通信系统通过引入频谱共享技术实现与广播系统的共用是近年来国内研究提出的一种新思路。本文对频谱共享应用的方案和若干关键技术问题进行了探讨,重点研究并提出了共享应用模式下的共存保护要求。     

浅谈数字媒体技术在精品课程网络资源共享中的运用

共享优质的教学资源是精品课建设的主要目的,精品课堂的共享可以分享优秀和成果的教学案例,最终发挥其的示范作用.精品课堂的共享可以促进课程建设的改革与发展,提高教学的质量.充分利用教学资源,真正让学生学会自主学习,为师生之间提供可以互动和交流的平台.本文提出,提高精品课程网站的便捷性,让网站的内容更加具有互动性,提高网络的流畅性,让界面更加具有友好性,都可以用数字媒体技术来解决.同时本文通过对信息技术在精品课程网站建设中的应用分析,提出了网络资源共享在精品课程建设中的重要作用.     

开放网络数据访问协议OPeNDAP的研究及应用

数据的共享有助于充分挖掘数据的价值,开放网络数据访问协议OPe NDAP面向地球科学数据提供一种通用标准的数据共享方式,目前在国际上已经成为一种事实上的标准。文章对OPe NDAP协议原理、应用模式、特点进行了系统的研究,面向气象数据共享目前存在的问题,提出引入OPe NDAP协议及相关技术来解决的途径。通过结合OPe NDAP的气象数据共享模型的设计和基于OPe NDAP服务器的气象数据共享实现,文章认为OPe NDAP是一种可行的气象数据共享技术。