Corrosion resistance of the anti‐sulfide steel in the CO2/H2S containing solutions

The present work primarily investigates the corrosion characterization of the common P110 steel and the anti‐sulfide P110SS steel in CO₂‐containing solution with or without hydrosulfuric acid (H₂S) at 70 °C. The electrochemical techniques such as potentiodynamic polarization sweep and electrochemical impedance spectroscopy (EIS) were used to disclose the differences of the corrosion mechanisms between both P110 and P110SS steels in CO₂‐containing solution with various additions of H₂S. The EIS data fitted by ZsimpWin software were analyzed and discussed. The experimental results indicated that H₂S could accelerate and also inhibit the corrosion attack according to the changes of corrosive environments.     

Domino群集在AS/400上的实现及应用

通过嘉兴电力局的应用作为实例,详细介绍了在AS/400上,如何实现Domino群集.主要包括群集的规划、群集的配置及群集的测试3大部分.并且结合实际,提出了在应用中需要考虑的问题及解决办法.     

莫糊-PID复合控制在燃烧控制系统中的应用

燃烧系统是一个具有大惯性、纯滞后、分布参数非线性的系统，PID调节以及双交叉限幅PID控制在燃烧系统中控制效果不理想、超调量和响应时间的矛盾不能解决、系统抗干扰的能力比较差。在培烧炉的控制中，采用双交叉限幅控制和模糊控制相结合的方法，选用西门子公司的S7—400PLC实现了上述控制功能，得到了比较好的控制效果。     

低悬浮物水样SS测定出现负值的探讨

低 SS(≤ 1 0 mg/L)水样的 SS测试过程中 ,天平的及时校准、冷却条件的严格控制、干燥剂的更换频率、滤纸等方面 ,对其测试结果有很大影响。对大量的试验数据进行对比 ,提出了相应的解决措施     

System Capacity and Access Control for Multimedia TDMA/SS Networks

In this paper, we study the system capacity and access control for the TDMA/SS (time division multiple access with spread spectrum) cellular networks supporting multimedia services. In the TDMA/SS system, time is divided into frames and each frame is further divided into slots. Only one user is allowed to transmit in a slot and spread spectrum technique is adopted to combat inter-cell interference. A packet can occupy more than one slot, depending on the user's data rate and quality of service requirement. We derive a necessary and sufficient condition for a group of users to be admissible for the TDMA/SS system and prove that its admission region contains that of the TDMA/CDMA system. In the TDMA/CDMA system, time is also divided into frames and each frame consists of several slots. The difference is that every packet occupies exactly one slot and multiple users can transmit their packets in the same slot. Numerical results show that the admission region of the TDMA/SS system can be significantly larger than that of the TDMA/CDMA system. To further increase bandwidth utilization and guarnatee delay bound requirements, several access control schemes are proposed. Simulation results are obtained for these access control schemes.     

TETRA电路模式控制实体信令软件实现

TETRA作为全球性数字集群标准,其技术和市场都在迅速发展。本文详细分析了TETRA移动台电路模式控制实体(CMCE-MS)协议,并给出其软件设计与实现的详细方案。     

基于西门子S7-400的造纸漂白工段PLC控制系统

介绍了漂白工段在制浆造纸工业中的重要性,针对漂白工段复杂的工艺特性,给出了基于西门子S7-400控制系统的结构及硬件配置.同时采用多模态控制算法实现对塔温的优化控制.     

SIMATIC S7-400H在膨胀机控制系统改造中的应用

文章介绍了SIMATIC S7-400H在膨胀机控制系统改造中的应用,总结了改造中的经验教训。减少设备故障,降低设备维护成本,消除了停产的风险(缺备件),对于正常生产缺少备件的用户来说,S5升级S7是一种切实可行的方法,值得借鉴。通过改造提高了生产的自动化程度,充分发挥了S7-400H系统的优势。     

直扩信号伪码的盲估计方法的研究

对直接序列扩频通信的信号检测方法进行了综述,重点讨论了自相关域检测方法、四阶累积量方法、谱分析与信号子空间分解法,其中四阶统积量方法和谱分析与信号子空间分解法的最低检测门限远低于相关算法,谱分析与信号子空间分解法在直接序列扩频(DS/SS)信号的伪码周期估计以及伪码序列盲估计中,利用功率谱二次处理结合信号子空间分解的方法可以实现对低信噪比DS/SS信号的估计。