The purpose of this project is to is to investigate the possibility of exploiting the flexibility inherent to micro air vehicle structures to create small-amplitude oscillations that delay stall and increase lift. Initially two-dimensional rigid airfoils undergoing small amplitude plunging oscillations are considered, this is then expanded to finite wings and finally flexible wings. For the 2D airfoil case two mechanisms of lift generation are identified: deflected jets for pre-stall angles of attack and convected leading- edge vortices for post-stall angles of attack. For rigid airfoils plunging with small-amplitude, two mechanisms of lift enhancement have been identified: deflected jets and convected LEVs. For finite wings oscillating at post-stall incidence, similar lift-enhancing convected LEVs are observed, however the flow field is more complicated. For oscillating flexible wings appropriate spanwise flexibility can significantly enhance lift performance. In terms of the flow field, the rigid wing exhibits weak vortical structures near the leading-edge, which are essentially the three-dimensional version of the LEV dipole observed for flat plate airfoils. Conversely the flexible wing exhibits a strong convected LEV, strong tip vortex and thus high lift.

关键词：翼型；攻角；长宽比；非对称流动；岔流

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Catalytic converters (CATCONs) are required by Federal law to be installed in nearly all gasoline- and diesel-fueled onroad vehicles used in the United States. About 85 percent of the light-duty vehicles and trucks manufactured worldwide are equipped with CATCONs (Ashok Kumar, Director, A1 Specialized Services & Supplies, Inc., written commun. July 10, 2012). These vehicles include buses, cars, light- and heavy-duty trucks, and motorcycles. Many offroad vehicles, such as trail bikes and all-terrain recreational vehicles, are also equipped with CATCONs, but offroad vehicles are not addressed in this paper (Manufacturers of Emission Controls Association, 2008). Portions of the CATCONs (called monoliths) are recycled for their platinum-group metal (PGM) content and for the value of the stainless steel they contain. The cerium contained in the monoliths, however, is disposed of along with the slag produced from the recycling process. Although there is some smelter capacity in the United States to treat the monoliths in order to recover the PGMs, a great percentage of monoliths is exported to Europe and South Africa for recycling, and a lesser amount is exported to Japan. There is presently no commercial-scale capacity in place domestically to recover cerium from the monoliths. Recycling of cerium or cerium compounds from the monoliths could help ensure against possible global supply shortages by increasing the amount that is available in the supply chain as well as the number and geographic distribution of the suppliers. It could also reduce the amount of material that goes into landfills.

关键词：大气；稀有气体；空气污染

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Many engineering systems can be characterized as complex since they have a nonlinear behaviour incorporating a stochastic uncertainty. It has been shown that one of the most appropriate methods for modelling of such systems is based on the application of Gaussian processes (GPs). The GP models provide a probabilistic non-parametric modelling approach for black-box identification of nonlinear stochastic systems. This chapter reviews the methods for modelling and control of complex stochastic systems based on GP models. The GP-based modelling method is applied in a process engineering case study, which represents the dynamic modelling and control of a laboratory gas-liquid separator. The variables to be controlled are the pressure and the liquid level in the separator and the manipulated variables are the apertures of the valves for the gas flow and the liquid flow. GP models with different regressors and different covariance functions are obtained and evaluated. A selected GP model of the gas-liquid separator is further used to design an explicit stochastic model predictive controller to ensure the optimal control of the separator.

关键词：非线性行为；高斯工程；控制器

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The integration of fuzzy systems, Wavelet theory, and neural networks has recently become a popular approach in the engineering fields for control of nonlinear systems. Therefore, the application of Fuzzy Wavelet Neural Network controllers is clearly obvious to investigators. A lot of research has been done in the control of nonlinear systems by using the models based on type-1 Fuzzy Logic Systems (FLS). However, they are regularly unable to handle uncertainties in the rules. This chapter develops a novel structure of Type-2 Fuzzy Wavelet Neural Networks (T2FWNN) to control a nonlinear system. This has been performed by invoking some of the specific advantages of wavelets, such as dynamic compatibility, compression, and step parameter adaptation along with a combination of type-2 fuzzy concepts regarding the neural networks abilities. The proposed network is constructed based on a set of TSK fuzzy rules that includes a wavelet function in the consequent part of each rule. This can provide appropriate tools on adaptation of plant output signal to follow a desired one. In this regard, the merits of utilizing wavelets and type-2 FLS simultaneously have been discussed and explored to efficiently handle the uncertainties. It is worth mentioning that the stability of the system is effectively dependent on the learning procedure and the initial values of the network parameters. Here, an adaptive gradient descent strategy is used to adjust the unknown parameters. Furthermore, the performance of the proposed T2FWNN is compared with the type-1 FLS networks. As investigated, this method has gained considerably high levels of accuracy with the reasonable number of parameters. Finally, the efficiency of the proposed approach is demonstrated via the simulation results of two nonlinear case studies.

关键词：模糊神经网络；非线性系统；控制

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Approximately 89% of the paved-road network in Kansas is asphalt surfaced (bituminous and composite). According to the Kansas Department of Transportation (KDOT), typical design performance period of hot-mix asphalt (HMA) pavement for new construction or reconstruction is approximately 12 years. In most cases, these pavements are overlaid as they reach the end of their design life. Both bituminous and composite pavements are usually overlaid with Superpave HMA for pavement preservation. The new highway program of KDOT also emphasizes pavement preservation. KDOT is currently seeking to extend the lives of Superpave mixes for these overlays through educated better selection of asphalt and aggregates. Thus, KDOT is contemplating use of the Hamburg Wheel Tracking Device (HWTD) as a performance tester.

关键词：沥青；路面；试验设备；骨料；建筑

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In the last decade, the demand of micro products and miniaturization has seen a wide spread growth. Currently, micro products and micro features are produced through conventional macro scale ultra-precision machines and MEMS manufacturing techniques. These technologies have limitations as conventional machining centers consume large energy and space. For mass production of micro components using non-silicon materials and real 3D shapes or free-form surfaces, mechanical micro manufacturing technology based machine tools are developed as an alternative method. The principle of "Small equipment for small parts" is gaining trend towards the investigation on micro-machine tools. One example of miniaturization of manufacturing equipment and systems is the Japanese micro-factory concept. Few micro-machines and associated handling micro grippers and transfer arms are developed to create micro-factory. The manufacturing processes are performed in a desktop factory environment. To explore the micro-factory idea, large number of micro machines can be installed in a small work-floor. The control of this micro factory concept for operation, maintenance and monitoring becomes a Cyber-physical system capable of producing micro-precision products in a fully-automated manner at low cost. Manufacturing processing data and condition monitoring of micro machine tools in a micro factory are the variables of interest to run a smooth process flow. Every machine out of hundreds of micro machines will have sensing equipment and the sensors data is being compiled at one place, ideally using wireless communication systems. One or two operators can run and monitor the whole micro-factory and access the machine if the fault alarms receive from any station. A variety of sensors will be employed for machine control, process control, metrology and calibration, condition monitoring of machine tools, assembly and integration technology at the micro-scale resulting in smooth operation of micro-factory. Single machine can be designed with a computer numerical control, but, flexible reconfigurable controllers are envisioned to control variety of processes that will lead to the development of open architecture controllers to operate micro-factory. Therefore, the control effort and algorithms have to utilize process models to improve the overall process and, ultimately, the product. Thus, we aim to introduce machine to machine (M2M) communication in the micro factory test bed. M2M communication enables micro actuator/sensor & controller devices to communicate with each other directly i.e., without human intervention, automating management, monitoring, and data collection between devices, as well as communicating with neighboring machines. All micro sensors communicate with a local short distance wireless network e.g. via Bluetooth piconet as well as with a centralized controller via WLAN 802.11 to exchange control/command from it. In this chapter, inherent issues are first highlighted where bulk micro-part manufacturing is carried out using large size machines. State-of-the-art micro machine tool systems designed and developed so far are discussed. With the help of precision engineering fundamentals and miniaturization scaling issues, a design strategy is formulated for a high precision 3-axis CNC micro machine tool as a model for micro-factory working. Based on this, a mathematical model is built that includes machine's design variables and its inherent errors. The volumetric error between tool/work-piece is evaluated from the machine's mathematical model and further used as an objective function to be minimized. Robust design optimization at micro machine development stage reveals the sensitivity analysis of each design variable. The optimization analysis employs different design of Experiment (DOE) techniques to make initial population that is governed by multi-objective genetic algorithm. Hence, the robust design is achieved for 3-axis micro machine tool using the essential knowledge base. The technique is used to remove the machine's repeatable scale errors via calibration and is known as error mapping. These errors are entered into the machine controller, which has the capability of compensating for the error. The machine does not need any extra hardware. Error mapping is a cost-effective tool in achieving volumetric accuracy in a micro manufacturing system.

关键词：微工厂；微型计算机；机器人网络物理系统

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The legged robots have emerged by the necessity of vehicles capable of travel and access safely on natural or unstructured terrains, in which vehicles with traditional travel systems (like the wheels) are unable to access, or if they achieve, they move on them with very low efficiency. However, despite the advantages of mobile robots with legs, there are limitations that hinder its use like the control of movement of their legs, the algorithm of locomotion, trajectory tracking and the obstacle avoidance. In our days, a very useful alternative applied to control systems is fuzzy logic; this one is capable of modeling mathematical complex systems. Therefore, fuzzy logic has been becoming popular in control systems for complex and nonlinear plants. The aim of this work is to make algorithms to control the hexapod robot body. The development of these algorithms uses fuzzy logic techniques for controlling the servomotors of the robot. Matlab algorithms are performed to establish a wireless communication using the ZigBee communication protocol, and we use the genetic algorithm toolbox from Matlab to make the control of the hexapod robot body in the "x-y" plane, this is a multi-objective optimization problem due to the stabilization of the robot body in "x" and the stabilization of the robot body in "y".

关键词：腿式机器人；控制器；访问安全

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This chapter presents the application of a particle swarm optimization (PSO) to a controller tuning in selected power electronic and drive systems. The chapter starts with a relatively simple tuning of a cascaded PI speed and position control system for a BLDC servo drive. This example serves as the background for a discussion on selecting the objective function for the PSO. Then the PSO is used in two challenging controller tuning tasks. This includes optimizing selected learning parameters in the adaptive artificial neural network (ANN) based online trained speed controller for an urban vehicle (3D problem) and selecting penalty factors in the LQR with augmented state (i.e. with oscillatory terms) for a three-phase four-leg sine wave inverter (15D problem). It is demonstrated with the help of these case studies why and where the PSO, or any other similar population based stochastic search algorithm, can be beneficial. Engineers encounter many non-straightforward controller tuning problems in power electronic systems and this chapter illustrates that in some cases it is relatively easy to reduce these tasks into the objective function selection problem. The relevant controller parameters are then determined automatically by the PSO.

关键词：粒子群优化；人工神经网络；搜索算法

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The Annual Energy Outlook 2013 (AEO2013) included several alternative cases in which hypothetical carbon dioxide (CO2) emission fees were imposed on fossil fuel consumers on an economy-wide basis.

关键词：大气；空气污染；二氧化碳

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The scope of this chapter is to trace the recent developments in the field of Intelligent Multiple Models based Adaptive Switching Control (IMMASC) and provide at the same time all the essential information about the conventional single model and multiple models adaptive control, which constitute the base for the development of the new intelligent methods. This work emphasizes on the importance and the advantages of IMMASC in the field of control systems technology presenting control structures that contain linear robust models, neural models and T-S (Takagi-Sugeno) fuzzy models. One of the main advantages of switching control systems against the single model control architectures is that they are able to provide stability and improved performance in multiple environments when the systems to be controlled have unknown parameters or highly uncertain parameters. Some hybrid multiple models control architectures are presented and a numerical example is given in order to illustrate the efficiency of the intelligent methods.

关键词：自适应转换控制；单模式；神经模型

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