IIR数字陷波器的设计及FPGA实现

IIR（无限冲激响应）数字滤波器在许多领域得到广泛应用.这里介绍了一种利用Matlab设计一个IIR数字陷波器的方法,接着在硬件实现时将其转化为二阶级联形式,以VerilogHDL语言书写模块,最后利用Altera公司的Quartus Ⅱ软件进行FPGA设计及仿真.     

Weibull分布基于定数逐次截尾寿命数据的统计分析

讨论Weibull分布基于定数逐次截尾寿命数据的参数估计，得到了参数的逆矩估计量和区间估计，模拟结果显示在中小样本情况下所给估计量优于参数的最大似然估计．     

论冯特心理学体系“两个世界”的划分

在科学心理学史上,冯特是一个不可或缺的奠基性人物。他不仅创建了该学科,而且创建了一个包含＂分裂＂的心理学思想体系,这已为心理学界所＂共识＂。但是冯特心理学体系＂两个世界＂的划分并不符合其原初的学术诉求,其＂两个世界＂亦绝非并列的关系,反而恰恰是一种不断演进、不断超越的生成关系,其间统觉对超越的实现发挥了功不可没的重要作用。     

基于FPGA的数字基带通信方案

该文设计方案采用FPGA(Field programmable gate array,即现场可编程门陈列)来实现数字通信中的时分复用和解复用功能,以三路固定时分复用器的设计为例,介绍了一个基于美国ALTERA公司的EPF10K10LC84 FPGA芯片开发的数字基带通信方案。该方案设计通过时分复用实现多路数据的传输,并采用EDA技术及自顶而下的设计思路。将时分复用主要硬件功能通过编程方式制作在两片FPGA芯片上,以MAX plus II软件为平台,以VHDL语言为工具,并且通过PCM编码电路、译码电路、显示电路等模块进行验证。该方案具有结构简单、成本低、性能稳定、抗干扰能力强的特点。     

阻抑催化光度法测定痕量硫氰酸根

在pH=4．5的HAc-NaAc介质中,痕量硫氰酸根能阻抑以2,2’-联吡啶为活化剂,阴离子表面活性剂十二炕基苯磺酸钠 (SDBS)为增溶剂,银催化过硫酸钾氧化天青(Ⅱ)的褪色反应,据此建立测定痕量硫氰酸根的阻抑催化动力学光度分析方法．该法检测限为2．0×10-2mg／L;线性范围为0．02-0．20mg／L.用于吸烟者和不吸烟者尿液中痕量硫氰酸根测定,结果满意．     

Symmetry properties of tetraammine platinum(II) with C_(2v) and C_(4v) point groups

INTRODUCTION The simplicity and elegance of some of theapplications of graph theory to chemistry can perhapsonly be compared with the results from group theorydealing with symmetry as a basic quality of a system.In some problems connectivity and symmetry arecombined and the question of determining symmetryproperties of graph becomes important. Given here are some definitions and notations.An automorphism of a graph G is a permutation g ofthe vertex set of G with the property that, for an…     

Listening to Mothers II: Report of the Second National U.S. Survey of Women's Childbearing Experiences: Conducted January–February 2006 for Childbirth Connection by Harris Interactive? in partnership with Lamaze International*

With permission from Childbirth Connection, the “Executive Summary” for the Listening to Mothers II survey is reprinted, here. The landmark Listening to Mothers I report, published in 2002, described the first national U.S. survey of women''s maternity experiences. It offered an unprecedented opportunity to understand attitudes, feelings, knowledge, use of obstetric practices, outcomes, and other dimensions of the maternity experience. Listening to Mothers II, a national survey of U.S. women who gave birth in 2005 that was published in 2006, continues to break new ground. Although continuing to document many core items measured in the first survey, the second survey includes much new content, exploring earlier topics in greater depth, as well as some new and timely topics.     

化学改性活性炭对Cu(Ⅱ)离子吸附性能的研究

将市售粉状活性炭用16%硝酸进行氧化,再用0.1mol.L-1的氢氧化钠进行处理,制得化学改性活性炭,并对其吸附性能进行了研究.实验结果表明,改性后的活性炭较改性前对Cu2 离子的吸附能力提高60%以上.     

A Study of the Effectiveness of Computer-Based Simulations in Teaching Computer Architecture

No abstract available for this article.