Internet中的物理资源

对Internet中的物理资源进行了较系统的介绍,主要内容有：综合物理网站、物理期刊网站和物理教学网站,其中重点介绍了美国和欧洲主要国家的物理网站和物理期刊网站,利用这些物理站点,可以方便的进行文献检索、物理会议查询,物理教学相关资料的查询和世界各大学物理系的查询;可以方便快捷的了解当今世界各国的物理教学学科研的最新进展,文中对各个物理站点的使用方法都一一做了详细的介绍,以方便读者使用。     

Internet与大学物理的双语教学

研究了大学物理的双语教学 ,指出因特网上对物理教学有用的在线资源的应用是很好的切入点 ,推荐一些十分有用的论点。     

国际互联网上的光谱学信息资源-Ⅰ

为了促进和方便光谱学工作者利用国际互联网,本文介绍了部分网上光谱学信息资源,主要包括光谱数据库,学术杂志,协会与组织,国际学术会议,与光谱学有着的机构、公司以及一部分光谱学工作者的网站及可检索的内容。     

我国掌握无汞扣式碱锰电池专利技术

日前中国电池工业协会主办的新闻发布会上宣布，我国已经掌握无汞扣式碱锰电池专利技术．由广东新利达电池实业有限公司发明的无汞扣式电池，是扣式电池无害化领域的重大技术突破；除在国内申请了实用新型专利外，还在美国、法国和中国香港等地申请了发明专利．目前，该技术已在新利达电池实业有限公司成功投入产业化，并出口美国等多个发达国家．一些欧美大公司的礼品、玩具已大量采购该公司的无汞扣式电池．     

视觉估计显示器gamma在Internet网络上的应用

使用自行开发出的基于Web的gamma估计程序,分别通过Internet对CRT和LCD显示器在暗、微暗和办公环境三种观察环境下,进行了视觉估计显示器gamma精确度研究实验.实验得出:不同实验者估计偏差范围,对CRT和LCD显示器分别是0.13和0.20;估计与测量结果的平均误差范围,对CRT和LCD显示器分别是0.07和0.17;gamma估计基本与观察环境无关;观察视角对LCD显示器gamma值影响很大;显示器的"亮度"和"对比度"设置,不影响视觉估计结果.     

国际互联网络（Internet）上的化学及分析化学信息

本文讨论了国际互联网络（Ｉｎｔｅｒｎｅｔ）在化学和分析化学中的应用，通过Ｉｎｔｅｒｎｅｔ可以有效地进行文献检索，获取信息，另外还介绍了查找实例并给出与化学有关的站点。     

视觉估计显示器gamma在Internet网络上的应用

使用自行开发出的基于Web的gamma估计程序,分别通过Internet对CRT和LCD显示器在暗、微暗和办公环境三种观察环境下,进行了视觉估计显示器gamma精确度研究实验.实验得出：不同实验者估计偏差范围,对CRT和LCD显示器分别是0.13和0.20|估计与测量结果的平均误差范围,对CRT和LCD显示器分别是0.07和0.17|gamma估计基本与观察环境无关|观察视角对LCD显示器gamma值影响很大|显示器的“亮度”和“对比度”设置,不影响视觉估计结果.     

怎样通过E-mail获取Internet信息

 如果你只能通过E-mail方式进入Internet网络,也请不要放弃Internet网络上的其他服务项目的尝试。尽管你的联网计算机还没有提供你可能听说过的诸如FTP、Gopher、Archie、Veronica、Finger、Whois、WAIS、World-Wide Web、Usenet等服务。即使你的计算机已能进入Internet网络方便地使用这些服务项目,应用E-mail服务器也能使你节约时间与资金。 本文介绍怎样通过E-mail方式做下列事情: (1)使用FTP索取文件; (2)通过Gopher软件来探取Internet网络信息资源; (3)应用Archie、Veronica或WAIS检索信息资源; (4)进入World-WideWeb; (5)进入Usenet新闻组。     

PC机如何进入Internet网

 随着现代通讯及计算机技术的飞速发展,Internet正在逐步进入人们的工作及生活空间。1994年,中国被获准进入Internet后,至今已有六个国际出口,联入Internet的主机已有数百台,用户也早已超过数千名。     

Information verification and encryption based on phase retrieval with sparsity constraints and optical inference

A novel optical information verification and encryption method is proposed based on inference principle and phase retrieval with sparsity constraints. In this method, a target image is encrypted into two phase-only masks (POMs), which comprise sparse phase data used for verification. Both of the two POMs need to be authenticated before being applied for decrypting. The target image can be optically reconstructed when the two authenticated POMs are Fourier transformed and convolved by the correct decryption key, which is also generated in encryption process. No holographic scheme is involved in the proposed optical verification and encryption system and there is also no problem of information disclosure in the two authenticable POMs. Numerical simulation results demonstrate the validity and good performance of this new proposed method.     

Worldwide nanotechnology development: a comparative study of USPTO,EPO, and JPO patents (1976–2004)

To assess worldwide development of nanotechnology, this paper compares the numbers and contents of nanotechnology patents in the United States Patent and Trademark Office (USPTO), European Patent Office (EPO), and Japan Patent Office (JPO). It uses the patent databases as indicators of nanotechnology trends via bibliographic analysis, content map analysis, and citation network analysis on nanotechnology patents per country, institution, and technology field. The numbers of nanotechnology patents published in USPTO and EPO have continued to increase quasi-exponentially since 1980, while those published in JPO stabilized after 1993. Institutions and individuals located in the same region as a repository’s patent office have a higher contribution to the nanotechnology patent publication in that repository (“home advantage” effect). The USPTO and EPO databases had similar high-productivity contributing countries and technology fields with large number of patents, but quite different high-impact countries and technology fields after the average number of received cites. Bibliographic analysis on USPTO and EPO patents shows that researchers in the United States and Japan published larger numbers of patents than other countries, and that their patents were more frequently cited by other patents. Nanotechnology patents covered physics research topics in all three repositories. In addition, USPTO showed the broadest representation in coverage in biomedical and electronics areas. The analysis of citations by technology field indicates that USPTO had a clear pattern of knowledge diffusion from highly cited fields to less cited fields, while EPO showed knowledge exchange mainly occurred among highly cited fields.     

基于相位恢复和数字全息的音频水印

提出了一种在数字全息技术中引入相位恢复算法的音频水印方法.用水印图像经相位恢复处理形成虚拟物光波与参考光波干涉,得到高对比度的傅里叶变换全息图.利用量化算法和离散余弦变换把数字全息图嵌入音频信号中,在水印提取过程中不需要原始音频信号的参与,并且采用密钥加强了水印的安全性.数值计算实验表明:该算法对有损压缩、重采样、低通滤波、噪音干扰等常用音频信号攻击均具有很好的稳健性.     

可变光阑光学衍射加密系统

为了克服双随机相位编码系统的局限性,提出基于光学衍射成像原理的图像加密方法.该方法在光学衍射加密系统中加入可变光阑,形成透光面积不同的振幅板,对明文进行加密,得出多个密文.解密时,通过相位恢复算法,从多幅衍射强度图像中恢复原始明文.仿真表明,由于只需要记录光波的衍射强度,在密文记录过程无需使用干涉装置,通过可变光阑可以方便地调节振幅板的透光面积,无需改变光学结构或者移动光学器件,因此,大大降低了加密过程实施的难度.     

Modified Gerchberg–Saxton (G-S) Algorithm and Its Application

The Gerchberg–Saxton (G-S) algorithm is a phase retrieval algorithm that is widely used in beam shaping and optical information processing. However, the G-S algorithm has difficulty obtaining the exact solution after iterating, and an approximate solution is often obtained. In this paper, we propose a series of modified G-S algorithms based on the Fresnel transform domain, including the single-phase retrieval (SPR) algorithm, the double-phase retrieval (DPR) algorithm, and the multiple-phase retrieval (MPR) algorithm. The analysis results show that the convergence of the SPR algorithm is better than that of the G-S algorithm, but the exact solution is not obtained. The DPR and MPR algorithms have good convergence and can obtain exact solutions; that is, the information is recovered losslessly. We discuss the security advantages and verification reliability of the proposed algorithms in image encryption. A multiple-image encryption scheme is proposed, in which n plaintexts can be recovered from n ciphertexts, which greatly improves the efficiency of the system. Finally, the proposed algorithms are compared with the current phase retrieval algorithms, and future applications are discussed. We hope that our research can provide new ideas for the application of the G-S algorithm.     

清热解毒类中成药中重金属含量的测定及评价

建立了微波消解电感耦合等离子体-原子发射光谱法(ICP-AES)测定中成药中Cu、Pb、Cd和Cr重金属含量的方法,并用该法测定了14种清热解毒类中成药中Cu、Pb、Cd和Cr等重金属的含量,并对中成药中重金属的污染状况进行了评价。方法的加标回收率为96.7%—108.0%,相对标准偏差(RSD)值小于5.4%。实验结果表明,中成药中Cr和Cd污染严重,没有被Cu和Pb污染。     

Spatial characteristics of joint application networks in Japanese patents

Technological innovation has extensively been studied to make firms sustainable and more competitive. Within this context, the most important recent issue has been the dynamics of collaborative innovation among firms. We therefore investigated a patent network, especially focusing on its spatial characteristics. The results can be summarized as follows. (1) The degree distribution in a patent network follows a power law. A firm can then be connected to many firms via hubs connected to the firm. (2) The neighbors’ average degree has a null correlation, but the clustering coefficient has a negative correlation. The latter means that there is a hierarchical structure and bridging different modules may shorten the paths between the nodes in them. (3) The distance of links not only indicates the regional accumulations of firms, but the importance of time it takes to travel, which plays a key role in creating links. (4) The ratio of internal links in cities indicates that we have to consider the existing links firms have to facilitate the creation of new links.     

智能检索引擎中的网络数据挖掘技术优化研究

随着计算机网络技术的不断发展,对于Web Service检索技术的要求也越来越大。并且现在网络环境当中数据信息流量十分庞大,对于信息可以做到深入搜索,实现全方位信息查询是非常有必要的。为此,利用网络数据挖掘技术在智能检索引擎中的应用,以文本描述为信息作为本文的研究对象,为用户提供运用查询要求实现概念检索功能。其中强调在智能搜索引擎当中的网络数据挖掘技术进行优化研究,从结构设计以及算法分析上总结出当前网络数据挖掘应用智能检索的可能性。最终设计出一种利用数据挖掘技术的智能检索模型,实现在众多网络数据中可以准确快速的进行详细的信息检索功能。     

Constrained regularization methods for ozone profile retrieval from UV/VIS nadir spectrometers

In this paper we present several constrained regularization methods for ozone profile retrieval from UV/VIS nadir sounding instruments such as GOME, SCIAMACHY, OMI and GOME-2. These methods extend the Tikhonov regularization and the iteratively regularized Gauss-Newton method with equality and inequality constraints imposed on the vertical column. It will be shown that this type of information, which is delivered by an independent algorithm like DOAS or GODFIT, significantly improves the accuracy and stability of the profile retrieval.