This paper proposes a design method for a wide-area measurements based power system stabilizer to improve the mode of concern, which is the dominant inter-area mode, in each system operating point. The design method, which is an iterative one, includes two steps: feedback signal selection and controller parameter tuning. The principle of the feedback signal selection is to maximize the residue of the mode of concern for the feedback signal while minimizing that of other modes. Then the tuning process can focus on only the mode of concern. The proposed method has been tested on the day time operating point of the IEEJ West 10-machine system. The result shows that the designed controller can improve the mode of concern significantly, while it can not affect much the others.

关键词：广域测量；电力系统稳定器；反馈信号选择

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The flow structures and their interactions behind side-by-side cylinders of unequal diameters at small gap ratios are studied by dye-flow visualization and particle image velocimetry at Reynolds number 1000. The whole-field mean and fluctuating velocity distributions and evolutions in the wakes are studied by the particle image velocimetry. As the gap ratio decreases, the mutual interaction of the wakes behind side-by-side cylinders pushes the recirculation region behind the large cylinder farther downstream at the expense of deterioration of the wake behind small cylinder. This change is important and may be relevant to the applications of passive flow control strategy.

关键词：并排侧缸；小的差距比；不等径

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Stamping is a long-established, widely used industrial process for economical high-volume production. It is used extensively in the automotive industry, as well as for production of white goods and many other products. In this book we present an approach, based on process control, to improve stamped part quality at reduced cost by eliminating tearing, wrinkling and springback. The concept is straightforward: measure punch forces and then adjust the blank holder (i.e., binder) forces (i.e., how tightly we hold the blank material in place) at various locations around its periphery and at various times during the stamping process to properly control the draw-in of blank material into the die. Of course, how to do this is the challenge! This book describes in detail how this simple goal can be achieved through real-time control technology.

关键词：冲压；钣金；过程控制

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Deformation substructures control plastic, creep, fatigue and fracture properties of ductile crystalline solids. The key ingredient of a substructure is a spontaneously formed dislocation arrangement - dislocation structure. The present notes provide 5 different, complementary points of view which present the dislocation structure formation as a multi scale phenomenon: (ⅰ) The basic concepts of dislocation theory and plasticity of single crystals and polycrystals (Section 2). (ⅱ) A "gallery" of commented pictures of dislocation structures as seen by a transmission electron microscope (Section 3). (ⅲ) Discrete dislocation dynamics (Section 4). (ⅳ) An attempt to formulate statistics of dislocations as a transition from discrete dislocation dynamics to continuum crystal plasticity capable of modeling dislocation structure formation (Section 5). (ⅴ) Two continuous models of dislocation structure formation: one dimensional model simulating a formation of vein structure and its transformation into a ladder structure of a persistent slip band (Section 6.1), and a model of misoriented dislocation cells (Section 6.2).

关键词：变形子控制；韧性结晶固体胶；静脉结构

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This chapter introduces a digital image processing algorithm to detect the obstacle in the path and according to the position of the obstacle, the speed of Autonomous Robotic Vehicle is controlled through PID based Speed control module. The camera mounted on Autonomous Robotic Vehicle captures image in such a way that the obstacle in image and actual vehicle position keep some distance to avoid collision. Based on the computed obstacle size, the vehicle actions are controlled. The streaming of the images of the path is done and each image is analysed through MATLAB Simulink based Video Processing Module. The control actions are taken based on the PID constants computed through MATLAB Simulink modules.

关键词：自主机器人车辆（ARV）；数字图像处理；速度控制

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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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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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This chapter presents a low-cost, flexible lab test-bench wind farm for advanced research and education on wind turbine and wind farm design and control. The mechanical, electrical, electronic and control system design of the wind turbines, along with the dynamic models, parameters and classical pitch and torque controllers are introduced in detail. Furthermore, the study presents a variety of experiments that (a) quantifies the effect of the number of blades in the aerodynamic efficiency, (b) estimates the generator efficiency, (c) validates the rotor-speed pitch control system, (d) proves the concept of maximum power point tracking for individual wind turbines, (e) estimates the aerodynamic C_p/λ characteristics, (f) calculates the power curve, and (g) studies the effect of wind farm topology configurations on the individual and global power efficiency. The experimental results prove that the dynamics of the test-bench corresponds well with full-scale wind turbines. This fact makes the test-bench wind farm appropriate for advanced research and education in wind energy systems.

关键词：风力发电机组的设计；风力发电机组造型；涡轮参数辨识

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The physics of collisionless shocks is a very broad topic which has been studied for more than five decades. However, there are a number of important issues which remain unresolved. The energy repartition amongst particle populations in quasiperpendicular shocks is a multi-scale process related to the spatial and temporal structure of the electromagnetic fields within the shock layer. The most important processes take place in the close vicinity of the major magnetic transition or ramp region. The distribution of electromagnetic fields in this region determines the characteristics of ion reflection and thus defines the con-ditions for ion heating and energy dissipation for supercritical shocks and also the region where an important part of electron heating takes place. In other words, the ramp region determines the main characteristics of energy repartition. All these processes are crucially dependent upon the characteristic spatial scales of the ramp and foot region provided that the shock is stationary. The process of shock formation consists of the steepening of a large amplitude nonlinear wave. At some point in its evolution the steepening is arrested by processes occurring within the shock transition. From the earliest studies of collisionless shocks these processes were identified as nonlinearity, dissipation, and dispersion. Their relative role determines the scales of electric and magnetic fields, and so control the characteristics of processes such as ion reflection, electron heating and particle acceleration. The determination of the scales of the electric and magnetic field is one of the key issues in the physics of collisionless shocks. Moreover, it is well known that under certain conditions shocks manifest a nonstationary dynamic behaviour called reformation. It was suggested that the transition from stationary to nonstationary quasiperiodic dynamics is related to gradients, e.g. scales of the ramp region and its associated whistler waves that form a precursor wave train. This implies that the ramp region should be considered as the source of these waves. All these questions have been studied making use observations from the Cluster satellites. The Cluster project continues to provide a unique viewpoint from which to study the scales of shocks. During its lifetime the inter-satellite distance between the Cluster satellites has varied from 100 km to 10000 km allowing scientists to use the data best adapted for the given scientific objective. The purpose of this review is to address a subset of unresolved problems in collisionless shock physics from experimental point of view making use multi-point observations onboard Cluster satellites. The problems we address are determination of scales of fields and of a scale of electron heating, identification of energy source of precursor wave train, an estimate of the role of anomalous resistivity in energy dissipation process by means of measuring short scale wave fields, and direct observation of reformation process during one single shock front crossing.

关键词：碰撞冲击；波在等离子体中；非平稳性

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In August 2012, the U.S. Environmental Protection Agency (EPA) and the National Highway Traffic Safety Administration (NHTSA) announced the final standard governing new-vehicle fuel economy for model years 2017 through 2025. The new standard maintains the current system of incremental increases in Corporate Average Fuel Economy (CAFE) requirements for new light-duty vehicles each model year, based on targeted decreases averaging approximately 5% per year in CO2 output per mile. This report compares the recent improvements in fuel economy with the projected CAFE performance levels anticipated by NHTSA. Recent trends in CAFE performance, when compared with the performance levels projected to be achieved by NHTSA, indicate that achieved CAFE performance has exceeded these anticipated levels for 2012 and 2013 model years--the two years that the current standard has been in effect. Additionally, achieved CAFE performance has consistently increased annually from model year 2008 through model year 2013. If the current trends in annual improvements continue, future CAFE performance is expected to continue meeting or exceeding the projected performance levels (and desired greenhouse gas reductions) contained in the latest CAFE standards.

关键词：大气；空气污染；空气健康

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