基于现场总线的彩钢板自动生产线控制系统

设计开发了彩钢板自动生产线控制系统,阐述了CC-LINK现场总线通信系统及三个控制从站的设计原理.实践表明,该控制系统控制精度高、投资少、运行可靠,满足了企业的需求.     

Influence of Dispersion of Nano-ZnO Particles in Polymer Matrices on Properties of Relevant Nano Composite Fibers

IntroductionIt is well knownthat nanoparticles have rich propertiesand are useful for functional composites . The nanometricsize ,leading to huge specific surface area up to or morethan1 000m2/g ,andtheir unique properties have attractedintensive interests . Thus many articles have elucidated thepreparation of polymer matrix nanocomposites( PMNC)[1 6]. Polymers are very i mportant matricesbecause of their flexibility and easy processing .Nanoparticles i mpart larger-size congeries because of…     

200 MN油压机液压系统的减振与降噪

通过测试200MN油压机液压系统表明动力流体和管路的耦合振动是液压系统主要的振动源.分析给出了液压泵和管路系统的模型,建立了液压管路及相关部件的传递函数矩阵,给出了解决特性阻抗的途径,为设计高压大流量油压机系统提供了参考.     

当代地理学研究前沿及研究思想发展

地理学是一门研究地球表层自然要素与人文要素相互作用及其时空变化规律的科学，以“格局-结构-过程-机理”的研究思路贯穿始终。随着新技术、新方法的使用以及观测资料的不断积累，实验测试数据质量的提高和数据量的增加，当今地理学的研究在空间尺度上同时向微观、宏观两个方向扩展，模型研究不断科学化。近十年来，“地球系统科学”发展迅速，地理学作为“地球系统科学”的重要组成部分，通过对地表多种自然与人文过程的耦合研究，正在不断完善认识与深化理论。本文在总结当代地理学研究前沿与发展趋势的基础上，对地理学思想的发展进行了评述。     

Analyzing and Designing Business Processes Management System Based on Transformation of Instantiated Ontology＇s State

The paper discusses efforts of finding a simple and transparent method to analyze business processes and developing its management system architecture. By introducing ontology and its state, the approach tried to find a unified representation and a flexible choreography of business processes. The main idea of the paper is the transformation of ontology＇s states, which are the most important scenarios of enterprises. The business activity composition, that is, case composition based on an AI technique, Case Based Reason （CBR）, which is to solve new problems by retrieving solutions to previous problems, and then store the modified solution. The main interest in CBR relies on that it allows a system to avoid past failures and exploit past successes.     

Synthesis and properties of a Pr（Ⅲ） complex with 2-acetylbenzimidazoledehyde-glycine Schiff-base ligand

Abstract The 2-acetyl-benzimidazoledehyde-glycine Schiff-base ligand and the corresponding Pr（Ⅲ） complex Pr2L3（NO3）3· 2CH3OH （L=C11H10N3O2） were synthesized in methanol and characterized by a series of methods, including chemical analysis, elemental analysis, TOF-MS, ^1H NMR, UV-, IR-, Raman spectra, thermal analysis, and the three-dimension fluorescence excitation and emission spectra. The Pr（Ⅲ） complex exhibits extraordinary water-solubility and the Pr（Ⅲ） hydroxide appears at pH≥13. The complex also possesses specific fluorescent properties. Thus, at the excitation wavelengths 200.0-280.0 and 260-350 nm the fluorescence bands were observed at 290.0 and 400.0 nm, respectively.     

Seasonal variation of snow microbial community structure in the East Rongbuk glacier, Mt. Everest

Mt. Everest, the zenith of the world, plays an impor- tant role in the global climate change. During the lastdecade, some studies on glacier and snow have been undertaken in this region. The climate and environment changes in the past hundred years have b…     

我国改革受阻深层原因分析

在改革过程中,我国利益表达主体多元化导致利益表达要求的多样性,利益表达客体角色错位引起利益表达信息的失真,利益表达能力的差异性及利益表达渠道畅通的有限性,利益表达效果与成本的不成比例性等,这些就是目前我国错综复杂的利益表达局面。它对处于攻坚阶段我国的改革产生一定阻力,并在一定程度上延缓了改革的进程。     

一种基于直扩码分多址系统的复信号空时扩频算法

基于直扩码分多址系统下行链路，提出了一种针对复信号的空时扩频算法．该算法采用发射分集技术，将空时分组编码与直接序列扩频相结合，依靠空时分组码和扩频码的双重正交特性以及复信号自身的特性，充分利用了空域和时域资源设计出新的收、发和解码算法，解决了复信号空时分组编码非正交所导致的解码复杂度过高的问题，将最大似然检测简化为一个线性过程．在独立瑞利衰落信道和给定收、发天线数的条件下，能够实现系统所能达到的最大的分集增益．理论分析及仿真结果表明，与未加扩频的发射分集系统及现有的空时扩频算法相比，该算法不仅能够显著提高数据传输速率，增大系统容量，还具有误码性能好，解码复杂度低、接收机结构简单等优点．     

浅议成本观念的更新和现代成本控制

企业要适应经济环境的变化，必须及时更新传统的成本观念。结合企业的实际情况，论述了充分运用现代成本控制方法，从管理的高度去挖掘降低成本的潜力，增强企业的市场竞争力。