Using scanning-tunneling microscopy and first-principles total-energy calculations, we have considered the structural properties of the so-called doped clusters formed by depositing additional 0.05 monolayer of In ont...
Using scanning-tunneling microscopy and first-principles total-energy calculations, we have considered the structural properties of the so-called doped clusters formed by depositing additional 0.05 monolayer of In onto the 4×3-periodicity magic-cluster array in the In∕Si(100) system. Low-temperature STM observations have revealed that most of the doped clusters have an asymmetric shape. According to the total-energy calculations, these clusters have plausibly Si6In8 composition. In such a cluster, one of the In atoms is mobile and can hop between four equivalent sites within a cluster. The hopping between sites, located in the different 2a×3a halves of the cluster, is characterized by the barrier of about 0.7eV, and this hopping becomes frozen at 55K. In contrast, the hopping between the neighboring sites within the same cluster half persists up to very low temperatures, as the barrier height here is an order of magnitude lower. Due to the above structural properties, the doped asymmetric Si6In8 cluster can be treated as a promising switch, logic gate, or memory cell of the atomic-scale size.
This paper presents EDUSCA, an EDUcational SCAda with OPC data access. EDUSCA was specially designed for automatic control education, research and operator training purposes. The developed system takes advantage of th...
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This paper presents EDUSCA, an EDUcational SCAda with OPC data access. EDUSCA was specially designed for automatic control education, research and operator training purposes. The developed system takes advantage of the facilities offered by the OPC communication architecture. The system allows the students to face real practical problems, could be used to train operators in plant supervision and also allows the implementation of research functionalities. Their main advantages of EDUSCA are: (i) it can be connected to any plant whenever it includes OPC communications; (ii) it is free of licenses, thus it can be installed in many computers as necessary; (iii) it can be adapted to each application requirements and (iv) it allows the implementation of a diverse set of functionalities, as for example, control algorithms.
According to the parallel binocular vision system, a method that uses common calibration board to realize automatic and accurate matching of the image corner pairs was developed, and the epipolar geometry of the syste...
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According to the parallel binocular vision system, a method that uses common calibration board to realize automatic and accurate matching of the image corner pairs was developed, and the epipolar geometry of the system was restored accurately. The coiner detection algorithm, the avoidance of the degeneration problem and the fundamental matrix iterative optimization algorithm based on rank-2 constraint were introduced. Experiment results proved the validity of the proposed method.
The goal to control the dynamics of high-rise buildings either to ameliorate the damage or prevent their destruction when subject to an earthquake excitation has been subject of extensive research. All known control d...
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The goal to control the dynamics of high-rise buildings either to ameliorate the damage or prevent their destruction when subject to an earthquake excitation has been subject of extensive research. All known control designs have advantages and disadvantages as well as operating limits. The application of sliding-mode control to controlling earthquake induced vibrations of a multi-story structural system as an active seismic compensation plus base isolation has been investigated. The performance has been compared to the one of traditional industrial controls, and relevant conclusions drawn. Simulation results, carried out using El Centro earthquake acceleration, have shown that the sliding mode control can decrease significantly displacements of the floors.
The different categories of robotic competitions organized all over the world are discussed. In climbing contests category, the task is to design a robot, which is going to climb a flat vertical wall while avoiding ob...
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The different categories of robotic competitions organized all over the world are discussed. In climbing contests category, the task is to design a robot, which is going to climb a flat vertical wall while avoiding obstacles in the path. In the fire fighting category, the objective of the contest is to build an autonomous mobile robot that can navigate through a square maze that represents a model house in order to find a lit candle representing fire in the house and extinguishes the fire in the shortest time. Furthermore, robot olympiad has been organized since 1999, by the International Robot Olympic Committee, which includes contests such as robot line tracing, legged robot obstacle race, FIRA Robot Soccer, RoboDancing, and RoboBasketball.
Common engineering approaches and modeling approaches from software engineering are brought together. For the domain of process automation an implementation oriented approach for an object oriented software developmen...
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The paper presents the development of real-time visual simulation systems for PLC programming education and training. This scientific area is being worked for several years at the automation group to which the authors...
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ISBN:
(纸本)9077381228
The paper presents the development of real-time visual simulation systems for PLC programming education and training. This scientific area is being worked for several years at the automation group to which the authors are affiliated. Yet, recent developments in computer graphics engineering are introducing dramatic changes in the area. The most appealing and challenging is to move from 2D to 3D virtual worlds. However, a much more complex modelling, a sophisticated technological integration and the real-time nature of the application introduce significant difficulties. The paper reveals how modern but low cost computer technologies successfully handle such difficulties. Two automated warehouses are used to illustrate the design of 3D virtual systems.
The control of dynamical systems with inherent non-linear characteristics has motivated research in non-linear control theory. Two main approaches to dealing with uncertainties in control systems design are adaptive a...
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Today Coriolis meters offer the beat performance in mass flow measurement. For those applications, where accuracy, low pressure drop and good cleanability is needed, the single straight tube is the best alternative. T...
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Windows operating systems (NT, 2000, XP, 2003) were not designed for real-time and time-critical applications. But, due to the market requirements, many of the monitoring and control applications are to use Windows NT...
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