In this chapter we revise basic principles and methods of model predictive control with a view towards applications in power electronics and drives. The simplest predictive control formulations use horizon-one cost functions, which can be related to well-established dead-beat controllers. Model predictive control using larger horizons has the potential to give significant performance benefits, but requires more computations at each sampling instant to solve the associated optimization problems. For particular classes of system models, we discuss practical algorithms, which make long-horizon predictive control suitable for power electronics applications.

关键词：预测控制；驱动器；控制器

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Polyelectrolytes, which are a macromolecule dissolved in water or polar solvent, have gained a wide attention among scientists and engineers for their wide application areas. Their different properties have allowed them to be used in many areas such as soap, body lotions, electrochromic devices, solid-state reference electrode systems, fuel cell exchange membranes, water treatment, waste treatment, paper production, corrosion protection, fuel cells, electrodialysis, contact lenses, membrane-based separations, drug delivery, and genetic science. Biocompatible polyelectrolytes are also utilized in biosensors and biomolecular recognition systems. Layer-by-layer (LbL) technique can be used to produce polyelectrolyte multilayer. Severe substrate such as gold, quartz, silicon, glass, plastic, stainless steel can be used in LbL technique. LbL technique is reproducible, cost-effective, and environmentally-friendly method. The characteristic properties of polyelectrolyte depend on the interaction between electrostatic forces. The degree of polymer charge can modify the electrostatic interactions. We examine the scaling theory according to Gennes et al. and Beurle and Nogovitsin in this chapter. After having discussed the scaling theory, we provide a basic introduction to properties of the neutron scattering and dynamic light scattering. In the end, we analyzed biopolymers and ionomers briefly. Polyelectrolytes (PEs) are generally denned as macromolecules, which when dissolved in water, dissociate to give highly charged polymeric molecules. As another definition, polyelectrolytes are polymers carrying either positively or negatively charged ionizable groups. These groups dissociate under appropriate conditions, and leaving ions on the chain and counter ions in the solution Examples of polyelectrolytes include polystyrene sulfonate, polyacrylic and polymethacrylic acids and their salts. DNA, proteins, nucleic acids, polysaccha-rides and other poly acids are given example to the natural polyelectrolytes. Polyelectrolytes are well known to play a vital role in nature and technology. PEs finds widespread use as solubilizing agents, phase separation agents, and rheo-logical property modifiers in daily life and technological applications. However, despite of their fundamental and practice importance, PEs systems still remain only poorly understood. This relates to the fact that their chemistry and physics are influenced by many controlling parameters, such as molecular weight, salt concentration, pH of the solution, etc.

关键词：聚电解质；高分子；天然聚电解质

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This chapter proposes a servo control of multiple-input multiple-output (MIMO) nonlinear systems approximated by piecewise bilinear (PB) models. The approximated model is found to be fully parametric. The input-output (I/O) feedback linearization is applied to stabilize PB control systems. The controller can be represented as a Look-Up-Table (LUT). We apply the servo control based on PB models to the Caltech ducted fan model. Although the controller is simpler than the conventional I/O feedback linearizing controller, the control performance based on PB model is the same as the conventional one. The example is shown to confirm the feasibility of our proposals by computer simulations.

关键词：非线性系统；非线性控制；控制器

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Soils are a source of oxides of nitrogen (NO(sub x) = nitric oxide and nitrogen dioxide), precursors for the production of ozone (O(sub 3)), an air pollutant in the troposphere. Production of nitric oxide (NO) occurs through soil microbial processes using ammonium from nitrogen fertilizer and manure inputs or soil mineral nitrogen (N). Emissions of NO(sub x) were measured in almond, alfalfa, tomato, wheat, and silage corn cropping systems during summer months to obtain estimates of NO(sub x) emissions that could potentially be used in regional models predicting O(sub 3) in the San Joaquin Valley. The lowest average NO(sub x) fluxes (40 g NO(sub x)-N ha(sup -1) h(sup -1)) were measured. These high NOx flux events are difficult to predict.

关键词：大气；空气污染；空气治理

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This article presents a thermo-mechanical approach to investigate heat transfer between solid and fluid phases in a model gasifier. A two-temperature equation approach is applied in addition to a macroscopic model for laminar flow through a porous moving bed. Transport equations are discretized using the control-volume method and the system of algebraic equations is relaxed via the SIMPLE algorithm. The effects on inter-phase heat transfer due to variation of medium permeability, thermal conductivity and thermal capacity are analyzed. Results indicate that for smaller medium permeabilities, as well as for higher solid-to-fluid thermal capacity and thermal conductivity ratios, enhancement of heat transfer between phases is observed.

关键词：移动床；模型气化炉；逆流；多孔介质；传播热量

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In this chapter, a new technique for multivariable closed-loop identification is presented. On the basis of process input and output data in the control loops, the process frequency-response matrix is estimated with signal decomposition and frequency spectrum analysis, and then a transform-function matrix is identified by least square method. The required input and output data are obtained while the processes are still in normal closed-loop operation. The closed-loop identification is applied to the boiler-turbine coordinated control system of power unit. Simulation example is given to show both effectiveness and accuracy of the identification method for boiler-turbine unit.

关键词：闭环辨识；频率响应；多变量系统；锅炉

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An Inertial Electrostatic Confinement Fusion (IECF) device is a compact fusion proton/neutron source with an extremely simple configuration, high controllability, and hence high safety. The common IECF device has constructed with an inner grid cathode. With this configuration, accelerated ions which move toward the cathode have probability of hitting the cathode to be lost, To increase neutron production rate (NPR) in this device, a grid-like rod cathode with a space at the center has been used in this experiment to increase a probability of accelerated ions to collide with each other at the center and this may increase a fusion rate. Furthermore, a cusp magnetic field, generated by small permanent magnets placed around chamber wall, is also used in this experiment in order to trap electrons and force to circulate near the anode, which will contribute to the generation of more ions near anode. Moreover, pulsed input mode has assigned in this experiment. An operation in pulsed mode is allowed us to expand experiment condition to a higher current range of a few amperes without damaging cathode and chamber wall.

关键词：融合；勾形磁场；坐月子

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In this Chapter the theory of nonlinear control systems is shortly described. The nonlinear feedback linearization control (FLC) and discontinues sliding mode control (SMC) are presented. Moreover, several applications of nonlinear control methods for induction motor drive are shown. The FLC guarantees the exactly decoupling of the motor speed and rotor flux control. Thus this control method gives a possibility to get very good behavior in both dynamic and steady states. The SMC approach assures direct control of inverter legs and allows using a simple table instead of performing complicated PWM calculation. Moreover the SMC is robust to drive uncertainties. The good behaviour of rotor flux and mechanical speed Sliding Mode Observers (SMO) is the important feature of the system. Therefore, presented approaches are very useful in a variety of applications and, in particular, in the drive systems and power electronics.

关键词：非线性控制系统；感应电机；不连续控制

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Ultra-thin body and buried oxide (UTBB) fully depleted (FD) silicon-on-insulator (SOI) MOSFETs are widely recognized as a promising candidate for 20 nm technology node and beyond, due to outstanding electrostatic control of short channel effects (SCE). Introduction of a highly-doped layer underneath thin buried oxide (BOX), so called ground-plane (GP), targets suppression of detrimental parasitic substrate coupling and opens multi-threshold voltage (V_(Th)) and dynamic- V_(Th) opportunities within the same process as well as the use of back-gate control schemes. Electrostatics, scalability and variability issues in UTBB MOSFETs as well as their perspectives for low power digital applications are widely discussed in the literature. At the same time assessment of UTBB FD SOI for analog and RF applications received less attention. This chapter will discuss Figures of Merit (FoM) of UTBB MOSFETs of interest for further analog/ RF applications summarizing our original research over the last years. Device analog/RF performance is assessed through the key parameters such as the transconductance, g_m, the output conductance, g_d, the intrinsic gain, A_v and the cutoff frequencies, f_T and f_(max). Particular attention is paid to (1) a wide-frequency band assessment, the only approach that allows fair performance prediction for analog/RF applications; (2) the effect of parasitic elements, whose impact on the device performance increases enormously in deeply downscaled devices, in which they can even dominate device performance. Whenever possible, we will compare FoM achievable in UTBB FD SOI devices with those reported for other advanced devices.

关键词：埋氧；硅绝缘体；FOM

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The United Nations Intergovernmental Panel on Climate Change (IPCC) has stated that the warming of the climate system is unequivocal, as is now evident from observed increases in global average air and ocean temperatures, widespread melting of snow and ice and rising global average sea level. In the coming decades, it is expected that these changes will result in regional climate impacts, including, but not limited to, permafrost thawing, increased tropical cyclone intensity, shifting tropical storm tracks, and an increase in the frequency of heat waves and heavy precipitation. As a result of these findings, concern is growing both in the United States and abroad (47) that these changes will have serious adverse impacts on transportation and civil infrastructure systems unless agencies take proactive steps to mitigate these issues.

关键词：大气；气候变化；空气质量

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