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991.
以浸没式超滤膜为核心的短流程净水工艺的应用与思考 总被引:1,自引:0,他引:1
以浸没式超滤膜为核心的短流程净水工艺自问世以来受到业界的广泛关注.该工艺为净水厂建设和改造提出了一条将预处理、超滤、浓水回收、污泥浓缩、排泥等工序集合在一个构筑物中运行的全新技术路线,有着广阔的应用前景.从该工艺各个环节的特点出发,进行从设计到运行的多角度思考,提出了一些自己的理解,抛砖引玉与大家共同探讨. 相似文献
992.
993.
Advances in wireless access technologies such as WiMax and LTE have accelerated the development of wireless video applications.Though existing erasure codes are designed for wireless data broadcasting,their potential can only be realized for wireless video broadcasting if the distortions associated with video packets and their complex decoding dependency are taken into consideration.In this paper,we propose the greedy video erasure code(GVEC)to minimize average video distortion by accounting for the temporal scalable decoding dependency among video frames e.g.I,P and B frames in MPEG.GVEC is a greedy algorithm and sufers from high computational complexity.For practical implementation,we have designed the joint video adaptation and erasure code(JVEC)with lower complexity,which can generate erasure codes on the fly to guarantee the decoding of important video frames.Simulation results show that the performance of JVEC is very close to that of GVEC,and is superior to that of existing erasure codes.Our results also show the existence of a performance tradeof between video distortion and video packet throughput. 相似文献
994.
Rongjin Huang Yeping Li Xiaoya He 《Canadian Journal of Science, Mathematics, & Technology Education》2013,13(4):293-306
Abstract In this study, we examined the views of 10 experts and 10 novices on effective mathematics instruction in China. We found that all the participants valued students’ mastering of mathematical knowledge and skills and their development in mathematical thinking methods and abilities. Compared with novice teachers, expert teachers emphasized the development of students’ mathematical thinking and higher order thinking abilities and properly dealing with important and difficult content points. In contrast, novice teachers were particularly concerned about the effectiveness of teachers' guidance. 相似文献
995.
Boris S. Mitavskiy Elio Tuci Chris Cannings Jonathan Rowe Jun He 《Natural computing》2013,12(4):473-484
The classical Geiringer theorem addresses the limiting frequency of occurrence of various alleles after repeated application of crossover. It has been adopted to the setting of evolutionary algorithms and, a lot more recently, reinforcement learning and Monte-Carlo tree search methodology to cope with a rather challenging question of action evaluation at the chance nodes. The theorem motivates novel dynamic parallel algorithms that are explicitly described in the current paper for the first time. The algorithms involve independent agents traversing a dynamically constructed directed graph that possibly has loops and multiple edges. A rather elegant and profound category-theoretic model of cognition in biological neural networks developed by a well-known French mathematician, professor Andree Ehresmann jointly with a neurosurgeon, Jan Paul Vanbremeersch over the last thirty years provides a hint at the connection between such algorithms and Hebbian learning. 相似文献
996.
Junjian Huang Chuandong Li Xing He 《International Journal of Control, Automation and Systems》2013,11(3):643-647
This paper further investigates the problem of intermittent control of a memristor-based Chua’s oscillator and presents the oscillator as the T-S fuzzy model system. Based on Lyapunov stability theory, we design an intermittent controller to guarantee the stability of the chaotic system. Simulation results are presented to verify the effectiveness of the method. 相似文献
997.
A scheme for generating the two-mode maximally path-entangled state of multi-photon, i.e., the so-called NOON state, through use of cavity QED techniques is proposed. In the present scheme, the entanglement between two spatial modes is established by guiding a laser pulse through a single atom cavity firstly, and then is transferred to the entanglement of the fields of the two cavities. The multi-photon state is generated in either one of the cavities via the strong atom-light interaction stimulated by the laser pulse adiabatically. Consequently, the desired optical NOON state is obtained. 相似文献
998.
We investigate the dynamics of quantum correlation between two separated qubits trapped in one-dimensional plasmonic waveguide. It is found that for a class of initial states, the quantum discord shows a sudden change phenomenon during the dynamical evolution. Furthermore, we demonstrate that the quantum discord can be enhanced if a proper product of the plasmon wave number and two qubits distance is chosen. Finally, we find that the non-zero quantum discord between two qubits can be created for the states without initial quantum discord during the time evolution of the system. 相似文献
999.
构皮滩水电站双曲拱坝底孔混凝土在施工过程中,针对底孔部位结构复杂、钢筋分布密集、混凝土种类多、标号高等技术特点,通过对施工模板规划布置及设计、混凝土下料控制、浇筑工艺及温度控制等采取合理的技术措施,保证了底孔施工的顺利进行。 相似文献
1000.
本文基于土石坝除险加固实际,对加筋土技术在土石坝出险加固中的应用进行探讨.利用ANSYS对某一土石坝现状和加筋状态进行二维有限元模拟,对前后的应力、位移结果进行分析比较.得出加筋在滑体土的中下部时效果最好、加筋层数越多,对坝体的变形控制的越好,但加强的效果逐渐减弱的结论. 相似文献