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41.
具有匹配不确定的奇异摄动系统的鲁棒控制 总被引:2,自引:0,他引:2
对于同时具有结构匹配不确定和系统不确定量的奇异摄动系统,利用Lyapunov稳定性理论进行了鲁棒性研究。给出了1个理想奇异摄动系统的稳定鲁棒控制也是不确定奇异摄动系统稳定控制的稳定条件和鲁棒界,讨论了鲁棒界及其随参数变化的变化范围。本文是王宪杰,高存臣已有结果的推广。 相似文献
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The upper layer (above 140 m depth) temperature in the western Philippine Sea near Taiwan was sampled using a coastal monitoring
buoy (CMB) with 15 attached thermistors during July 28–August 7, 2005. The data were collected every 10 min at 1, 3, 5, 10,
15, and 20 m using the CMB sensors, and every 15 sec at 15 different depths between 25 m and 140 m. Internal waves and solitons
were identified from the time-depth plot of the temperature field. Without the internal waves and solitons, the power spectra,
structure functions, and singular measures (representing the intermittency) of temperature field satisfy the power law with
multi-scale characteristics at all depths. The internal waves do not change the basic characteristics of the multifractal
structure. However, the internal solitons change the power exponent of the power spectra drastically, especially in the low
wave number domain; they also break down the power law of the structure function and increase the intermittency parameter.
The physical mechanisms causing these different effects need to be explored further. 相似文献
44.
In this paper, we focus on the status and trends of the current Korean fisheries management regime. Specifically, this paper briefly introduces the Korean conventional fisheries management regime (KCFMR) and discusses its problems and limitations. In describing policy evolution, this paper finds reasons why the Korean government has chosen a TAC system, an output control approach, besides input control approaches in force for almost a century. This paper also describes the evolution of the Korean TAC system, which is carrying out a pivotal role in Korean fisheries development, and analyzes problems of the Korean TAC system. Finally, this paper gives a perspective on expanding the Korean TAC system toward Output Control Systems (OCSs) such as Individual Quotas (IQs), Individual Vessel Quotas (IVQs), Individual Transferable Traps (ITTs), Community Quotas (CQs), and Individual Transferable Quotas (ITQs). 相似文献
45.
据开发应用水产饲料膨化机实践,初步论述了膨化机生产能力与动力匹配,螺杆设计参数长径比,物料在腔内滞留时间,膨化腔设计及其温度调控,并提出改进设计的见解. 相似文献
46.
The effects of scattering and resonance on the energy dissipation of an internal tide were investigated using a two-dimensional
model which is a reassembled version of the theoretical generation model devised by Rattray et al. (1969) for internal tide. The basic character of the scattering process at the step bottom was first investigated with a
wide shelf model. When the internal wave incited from a deep region (Region II) into the shallow shelf region (Region I),
a passing wave into the shallow region, a reflected wave into the deep region, and a beam-like wave, i.e. a scattered wave
(SW), emanated at the step bottom. The SW, which consists of the superposition of numerous internal modes, propagated upward/downward
into both regions. The general properties of the SW were well expressed around the shelf edge, even in the present model with
viscosity effect. The amplitude of the SW decreased dramatically when the depth of the velocity maximum of the incident internal
wave in Region II corresponded with the depth of the shelf edge. In the narrow shelf model, where the decay distance of the
internal wave in Region I is longer than the shelf width, the incident internal wave reflected at the coast to form a standing
wave. When the internal wave in Region I is enhanced by the resonance, the energy of the SW in Region II is also intensified.
Furthermore, the energy of the modes in Region II predominated when the velocity maximum is identical to that of the dominant
mode in Region I. These results suggest that the spatial scale of shelf region is a very important factor governing the energy
dissipation of the internal tide through reflection and scattering in a narrow shelf. 相似文献
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本文对用于模式分类、函数逼近、参数估计的多层感知器 (MLPs)给出 1个清晰的关于内部行为的解释。作者以单隐层的 MLP为例 ,论述了关于 MLP的内部行为的半线性分析理论。对受训的MLP,将隐层单元的输出分别定义为网络输出的正、负“内部分量”;定义内部分量的连接权重集为给定问题的“内部判别模式”;建立了 MLP和模糊集相结合的新模型 ;分析了 MLP的结构为 N- 2 - 1和N- H- 1 ,给出权重初始化的方法 ;提出了 1种从受训神经 -模糊模型 (NFMs)中提取知识的全新的具有实用价值的方法。 相似文献
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