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4231.通过柔性交流输电系统对电力系统稳定进行线性控制设计与仿真
[电气机械和器材制造业] [2014-03-14]
Inter-area oscillations in power systems are triggered by, for example, disturbances such as variation in load demand or the action of voltage regulators due to a short circuit. The primary function of the damping controllers is to minimize the impact of these disturbances on the system within the limited dynamic rating of the actuator devices (excitation systems, FACTS-devices). In H_∞ control term, this is equivalent to designing a controller that minimizes the infinity norm of a chosen mix of closed-loop quantities.
关键词:光机电;电力系统;柔性交流输电系统;线性控制
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4232.量子搜索算法研究——专家算法与几何参数
[信息传输、软件和信息技术服务业] [2014-03-14]
We introduce the new framework of natural continuous time quantum search algorithms, that in contrast to the adiabatic quantum algorithms, require neither the ground state initialization nor the adiabatic change of the Hamiltonian parameters. We derive a slightly more general bound for the cumulative matrix multiplicative weights algorithm and introduce the first iterative matrix multiplicative weights algorithm with the same small performance regret. Furthermore, we address the following question:”what is the minimal size quantum circuit required to exactly implement a specifiednqubit unitary operationU, without the use of ancillaqubits?” finally we investigate then-dimensional hypercube quantum random walk(QRW) as a particularly appealing example of a quantum walk because it has a natural implementation on a register onnqubits.
关键词:量子搜索;专家算法;几何算法;矩阵多乘加权算法;量子线路;量子随机行走;非零和博弈
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4233.通过柔性交流输电系统对多个工作点电力系统稳定进行控制
[电气机械和器材制造业] [2014-03-14]
Power systems may operate on several operating conditions including post-fault operating conditions where it is challenging to design a FACTS damping controller that can achieve satisfactory performance over several operating conditions. When the nonlinear power system model is linearized around these operating conditions, a set of linearized state equations can formulate the multi-model system. So in principle the control design for the system with several operating points is to design a common controller for the multi-model system. Basically the output
关键词:光机电;电力系统;柔性交流输电系统
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4234.智能电网环境下的节能建筑控制:一种网络物理系统方法(CPS)
[信息传输、软件和信息技术服务业,建筑业] [2014-03-14]
We present a physics-based mathematical model of thermal behavior of buildings,along with a novel Parameter Adaptive Building (PAB) model framework to update the model parameters.We then address the "Cyber-Physical" aspect of a building HVAC system in the design flow.The last part of this dissertation is centered on the role of smart buildings in the context of the smart grid.
关键词:智能电路;节能建筑;信息物理系统
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4235.在试生产放射性同位素动力系统的最终整合活动中的行星保护问题
[电气机械和器材制造业] [2014-03-14]
The Advanced Stirling Radioisotope Generator (ASRG) is a next-generation radioisotope-based power system that is currently being developed as an alternative to the Multi-Mission Radioisotope Thermoelectric Generator (MMRTG). Power sources such as these may be needed for proposed missions to solar system planets and bodies that have challenging Planetary Protection (PP) requirements (e.g. Mars, Europa, Enceladus) that may support NASA s search for life, remnants of past life, and the precursors of life. One concern is that the heat from the ASRG could potentially create a region in which liquid water may occur. As advised by the NASA Planetary Protection Officer, when deploying an ASRG to Mars, the current COSPAR/NASA PP policy should be followed for Category IVc mission. Thus, sterilization processing of the ASRG to achieve bioburden reduction would be essential to meet the Planetary Protection requirements. Due to thermal constraints and associated low temperature limits of elements of the ASRG, vapor hydrogen peroxide (VHP) was suggested as a candidate alternative sterilization process to complement dry heat microbial reduction (DHMR) for the assembled ASRG. The following proposed sterilization plan for the ASRG anticipates a mission Category IVc level of cleanliness. This plan provides a scenario in which VHP is used as the final sterilization process. Keywords: Advanced Stirling Radioisotope Generator (ASRG), Planetary Protection (PP), Vapor hydrogen peroxide (VHP) sterilization.
关键词:光机电;电力系统;先进斯特林放射性同位素发生器(ASRG);行星保护(PP)
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4236.电力系统中具有高穿透风电场的电压控制研究
[电气机械和器材制造业] [2014-03-14]
The high penetration of wind farms in the transmission system causes difficulty for system operation such as voltage fluctuation, optimal system operation. In this study, the voltage fluctuation caused by output variation of wind farms (WF) is considered. In the conventional system, static condensers (SCs) play the role to keep the system voltage in the proper range with load change. Then, generation variation of WFs causes nodal to pass over the upper limit. Thus, the injected capacity of SCs is necessary to control for preventing overvoltage risk passing over the predefined value. The control capacity of SC is determined by loop calculation basing on sensitivity of SCs.
关键词:光机电;电力系统;电压控制;蒙特卡罗模拟
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4237.通过柔性交流输电系统进行稳态电力系统电压稳定分析与控制
[电气机械和器材制造业] [2014-03-14]
Voltage stability analysis and control become increasingly important as the systems are being operated closer to their stability limits including voltage stability limits. This is due to the fact that there is lack of network investments and there are large amounts of power transactions across regions for economical reasons in electricity market environments. It has been recognized that a number of the system blackouts including the recent blackouts that happened in North America and Europe are related to voltage instabilities of the systems.
关键词:光机电;电力系统;柔性交流输电系统
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4238.为有效的局域场增强设计光学天线
[计算机、通信和其他电子设备制造业] [2014-03-14]
In this dissertation, we theoretically derived the local enhancement of the optical antenna and found that optimized radiation and small gap spacing are required for maximum field enhancement of the antenna. To address these parameters, we experimentally demonstrated three different designs of optical antennas. First, we report on applying a dipole antemma on a ground plane for radiation engineering. Secondly, we report on a patch antenna on gound plane for the uniform sub-5 nm gap spacing. Finally, we present a novel optical antenna design—thearch-dipole antenna—which has radiation efficiency and small gap spacing(5 nm) fabricated by CMOS-compatible deep-UV spacer lithography.
关键词:局域场;场增强;光学天线;偶极天线;贴片天线;设计
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4239.稀疏主成分分析的算法与应用
[信息传输、软件和信息技术服务业] [2014-03-14]
In this dissertation, we first discuss several formulations for Sparse PCA, as well as the algorithms for solving the formulations and a few greedy methods. We then develop a block coordinate ascent algorithm for solving DSPCA with better dependence on problem size. We show that our algorithm converges much faster than the existing first-order algorithm in practice and demonstrate that our code can handle huge real data sets. We also demonstrate that Sparse PCA does bring more interpretability and hence gives rise to new interesting findings in various real data sets.
关键词:稀疏主成分分析;二维对称主成分分析;区域共坐标上升算法;共坐标上升算法;文本数据分析;半定松弛
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4240.一种低压、高电流的隧道晶体管的设计
[计算机、通信和其他电子设备制造业] [2014-03-14]
关键词:隧道晶体管;隧道场效应晶体管;频带边缘陡度