高陡坡运输碾压混凝土抗分离溜管的 研制与应用

为解决黄花寨水电站大坝工程高陡坡碾压混凝土运输问题,根据混凝土拌和物流变体特征,通过试验研制出能改变混凝土运行状态、控制混凝土输送速度,并能使混凝土在输送过程多次拌和的抗分离溜管。该抗分离溜管结构简单、操作简便,运行安全,制作及使用费低,在高陡坡条件下输送碾压混凝土,可以防止混凝土分离、保证混凝土质量,具有良好的推广价值。     

黄河海勃湾水利枢纽取水影响分析

黄河海勃湾水利枢纽是一座防凌、发电等综合利用的大型水利枢纽。重点从工程建成后对区域水资源、水域纳污能力、坝下河段最小生态水量、水温、水质、水生生物、西鄂尔多斯国家级自然保护区以及内蒙古河段防凌等方面的影响进行了详细的分析论述,总结了水利水电建设项目水资源论证中取水影响分析的经验以及需重点关注的问题,可为类似建设项目水资源论证取水影响分析提供参考。     

我国山洪灾害防治技术研究综述

针对我国防洪减灾工作中亟待解决的山洪灾害问题,总结了国内山洪灾害防治技术的研究成果,从山洪灾害的成因、预测预报技术、预警技术、监测预警系统建设、灾情风险评估技术、形成机理、防治区划及防治对策等7个方面对我国山洪灾害防治技术主要成果进行分析,探讨了当前存在的不足及今后研究的方向。     

以浸没式超滤膜为核心的短流程净水工艺的应用与思考

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.     

基于ANSYS的重力坝建基面等效应力计算

采用ANSYS进行重力坝坝体应力分析时,坝踵、坝趾等角缘部位存在应力集中现象,转化为等效应力可以有效地避免这个现象,但ANSYS没有提供专门的等效应力计算模块.本文基于ANSYS软件计算重力坝应力,采用VB可视化编程直接访问ANSYS数据库,结合等效应力计算公式实现对重力坝建基面等效应力计算,并通过算例验证了其实用性、...     

Joint video adaptation and erasure code for video broadcast in wireless networks

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.     

What Constitutes Effective Mathematics Instruction: A Comparison of Chinese Expert and Novice Teachers’ Views

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.     

Geiringer theorems: from population genetics to computational intelligence, memory evolutive systems and Hebbian learning

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.     

Stabilization of a memristor-based chaotic system by intermittent control and fuzzy processing

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.     

A scheme for generating a multi-photon NOON state based on cavity QED

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.