微型集散系统通用过程控制软件包

本文给出一种新的基于ＭＣＳ－５１单片机集散系统通用过程控制软件包的设计原理及其实施方法。文中重点地阐述了微型集散系统的构在民，通用过程控制软件的自动生成，主要数据结构与程序结构，实现方法及关键技术等。本软件包是采用ＴＵＲＢＯＣ２．０版本和ＭＣＳ－５１泄编语言编程的，并通过了ＭＣＳ－５１组合软件的编译，形成了可用的目标码程序系统。     

全金属反射光学系统结构的有限元分析

用有限元分析方法对全金属反射光学系统在各种受力状态下的变形、应力及固有频率做了全面的分析，并给出了结构多次优化后的分析结果。     

某厂锆（Zr）生产流程中不同产物的天然放射性核素含量测定

本文报道了某厂锆(Zr)生产流程中原料(锆英砂,主要成份为 ZrSiO_4)、半成品(ZrC,ZrCl_4)、废渣和成品锆中天然放射性核素~(238)U、~(226)Ra、~(232)Th 和~(40)K 含量测定结果。采用 NaI(Tl)γ能谱法进行测定,结果表明,原料、半成品和废渣中都含有一定的放射性,各生产环节应采取适当的防护措施;成品锆中基本不含放射性,可安全地应用于各个生产和生活领域。     

长期不同施肥对玉米田间杂草生物多样性的影响

通过田间小区试验,研究了长期不同施肥对田间杂草总密度、优势杂草组成及生物多样性的影响。结果表明:综合施用N、P、K肥,不仅降低了田间杂草的总密度,降低了优势杂草在群落中的比重,而且有利于维持田间杂草的生物多样性;不施用N或P肥,田间杂草的总密度增大,优势杂草的比重也明显增强,但不利于维持田间杂草的生物多样性。所以,平衡施用N、P、K肥,有利于维持农田生态系统中的生物多样性,并能更好地进行杂草控制。     

1997年度大中型钢铁企业节能工作情况综述

第九次节能工作会议后，冶金工业掀起了节能降耗的新高潮。各企业都从本单位 实际出发，狠抓节能降耗工作，节能增效成绩显著。大中型钢铁生产企业全年节能３５０万ｔ标煤，超 出１９９７年初冶金工作会议确定的全行业节能３００万ｔ目标。创造效益２８亿元。     

为流域管理机构立法

本文主要借鉴美国田纳西河流域的管理职权立法经验，对中国江河流域机械法案的内容框架进行探讨：流域机械法的地位；流域机械的地位；流域机构管理人员组成、任免、待遇规范及工作制度；流域机构的责、权、利、罚规则；与地方各行政部门尤其是环保、城建、地质矿产等部门的关系。     

A multipurpose audio watermarking algorithm with synchronization and encryption

We propose a new multipurpose audio watermarking scheme in which two complementary watermarks are used.For audio copyright protection,the watermark data with copyright information or signature are first encrypted by Arnold transformation.Then the watermark data are inserted in the low frequency largest significant discrete cosine transform(DCT) coefficients to obtain robustness performance.For audio authentication,a chaotic signal is inserted in the high frequency insignificant DCT coefficients to detect tampered regions.Furthermore,the synchronization code is embedded in the audio statistical characteristics to resist desynchronization attacks.Experimental results show that our proposed method can not only obtain satisfactory detection and tampered location,but also achieve imperceptibility and robustness to common signal processing attacks,such as cropping,shifting,and time scale modification(TSM).Comparison results show that our method outperforms some existing methods.     

Convex relaxation for a 3D spatiotemporal segmentation model using the primal-dual method

A method based on 3D videos is proposed for multi-target segmentation and tracking with a moving viewing system. A spatiotemporal energy functional is built up to perform motion segmentation and estimation simultaneously. To overcome the limitation of the local minimum problem with the level set method, a convex relaxation method is applied to the 3D spatiotemporal segmentation model. The relaxed convex model is independent of the initial condition. A primal-dual algorithm is used to improve computational efficiency. Several indoor experiments show the validity of the proposed method.     

基于聚类分析的新书推荐

针对大多数图书馆管理系统中的个性化服务中的新书推荐只是定时将新到馆的图书罗列出来让读者浏览进行推荐,推荐效果差的问题。本文在比较三大常用的推荐技术的优缺点后,采用基于聚类分析的推荐算法推荐新书,并具体给出实现的方法。     

Controlled experiments to study corrosion effects due to external varying fields in embedded pipelines

We present controlled laboratory tests carried out to study corrosion effects due to induction currents on pipes embedded in environments with electrical resistance lateral discontinuities. Sacrificial anodes were connected to underground pipes, and corrosion rates were estimated by measuring the mass loss in each anode. We considered 1 Hz and 50 Hz inducting fields, and the effects produced on the pipes were compared with cases without an external field. The results indicated an increase in the corrosion rate when the pipe was under the effect of induction currents, particularly where there was a change of electrical resistance in the soil.