基于遗传算法和神经网络混合优化的配煤控制

在配煤炼焦中 ,配煤比是影响焦炭质量的主要因素 .为稳定焦炭质量就要求配煤比实时性、自适应性好 ,因此采用混合优化算法分两步进行配煤比计算 .首先 ,根据焦化反应机理 ,采用神经网络建立焦炭质量预测模型 ,并通过遗传算法 ( GA)训练权值 ,从而提高模型自适应性 .其次 ,采用 GA实现配煤比定量计算 ,克服了以往基于知识的定性分析方法中对经验的依赖 .通过系统仿真 ,证明该方法较已有方法预测精度高、实时性好     

碳纳米管作为载体在邻硝基甲苯多相催化加氢中的应用

采用脉冲法进样，用邻硝基甲苯常压下气相加氢生成邻甲基苯胺为探针反应研究了纳米碳管负载镍催化剂的催化性能。分别评价了Ni负载在纳米碳管，活性炭，γ－Al2O3,SiO2上的催化活性，实验结果表明：在实验条件下，碳纳米管负载镍作催化剂的反应物的转化率和产物的选择性分别是80％和1005，转化率分别是二氧化硅负载内化剂的2．36倍，活性炭负载镍催化剂的1．83倍和三氧化二铝负载镍催化剂的1．49倍。     

渤海两油田油井堵塞原因分析及化学解堵试验

简要介绍了埕北油田和绥中36－1油田的储层特点及钻完井方式和原油特性，对两油田油井的堵原因进行了分析，并对油井解堵施工工艺技术进行研究。在此基础上研制出针对有机垢的解堵剂YS－01进行现场试验，试验结果表明：化学解堵剂YS－01可以很好地解除埕北油田和绥中36－1油田油井近井地带有机垢堵塞，增产效果十分明显；9口解堵井平均有效期已超过200天，经济效益十分显著。其成果对于埕北油田和绥中36－1油田相类似油田的油井管理、堵塞原因分析、施工工艺技术研究、解堵剂研制、解堵选井及化学解堵施工具有参考价值。     

Multi-Domain Model of Faulty Stator Core for Thermal Effects and Losses Evaluation

In this work, a multi-domain model of the stator core of an electric machine is presented. Its electromagnetic behavior and the thermal dynamics are represented using Bond Graph. This approach makes apparent the topology of the machine and the energy exchange. This feature enables the model for the easy representation of faults and analysis of their consequences in the thermal/magnetic/electric domain. The proposed model is used for reproducing the behavior of the stator core during an inter-laminar insulation test. The model is capable to reproduce the thermal distribution when a fault in the stator core occurs. This contribution helps to estimate the additional iron losses due to the stator core fault based on the thermal distribution. Additionally, this methodology could help to define the proper maintenance intervention to be performed on the machine.     

Precision analysis of kinetic modelling estimates in dynamic contrast enhanced MRI

Object  

Dynamic contrast enhanced MRI and pharmacokinetic modelling provide a powerful tool for tumour diagnosis and treatment evaluation. However, several studies show low reproducibility of the technique and poor precision of the transendothelial transfer constant K ^trans. This work proposes a theoretical framework describing how finite signal-noise-ratio (SNR) in the MR images is propagated throughout the measurement protocol to uncertainty on the kinetic parameter estimates.     

Optimizing performance in switched-reluctance drives

This article discusses the requirements of electric vehicle traction drives and the consequences to the control strategies of a switched reluctance motor drive. The selection of these control strategies for different operating regions in the torque-speed diagram is also discussed. To test different control strategies, a specialized simulation program was constructed. The simulation results and the implementation of the optimization strategies are discussed. Finally, the measurement methods and the test results are presented     

RF MEMS for ubiquitous wireless connectivity. Part I. Fabrication

The aim of this article to expose the impact and status of the application of RF-MEMS switchable capacitors, varactors and switches in the three elements of this paradigm, namely, handsets, base stations, and satellites. In particular, issues such as system-level motivation/justification for RF MEMS, device requirements, high-volume manufacturing, packaging, and state-of-the-art performance and reliability, are presented.     

Online Signal Injection Through a Bus-Referenced Current Transformer

An online signal injection approach based on a special current transformer is proposed as part of a solution for improving the test setup of transfer function diagnostics of transformers. However, the method is general and applicable to many types of substation equipment, such as circuit breakers and transmission lines. The system allows a high-power, high-frequency test signal to be injected directly on a high-voltage bus of an energized system. Due to the self-contained nature of the injector, no external power supplies or signal generators are needed and the design does not need to be ground-referenced. The system can thus be at the bus potential. In conjunction with wireless communication for control, no isolator bushings are required and the device can be constructed as a sleeve to be mounted around the busbar. This allows for economical retrofitting to existing installations. In this paper, the operational need for such an injection device is discussed, followed by the theory behind the proposed concept. Finally, a low-voltage, optically controlled, self-powered prototype is designed and demonstrated online to show the practical validity of the concept.     

Influence of Anodizing Parameters on the Electrochemical Characteristics and Morphology of Highly Doped P-type Porous Silicon

Silicon - Controlling pore structure, e.g. pore diameter, size and distribution of porous silicon (PS) is highly needed for technological applications such as microfluidic operation and filtration...     

纳米级碳酸钙的制备

本文简要介绍了纳米级碳酸钙的制备