Video and User′s Data Multiplexing in Desktop Video Conferencing Systems

１ＩｎｔｒｏｄｕｃｔｉｏｎＩｎｄｅｓｋｔｏｐｖｉｄｅｏｃｏｎｆｅｒｅｎｃｉｎｇｓｙｓｔｅｍｓ，ｔｈｅｒｅａｒｅｔｗｏｋｉｎｄｓｏｆｄａｔａ：ｃｏｎｔｉｎｕｏｕｓｍｅｄｉａｓｔｒｅａｍａｎｄｕｓｅｒ′ｓｄａｔａｔｈａｔｎｅｅｄｔｏｂｅｔｒａｎｓｍｉｔｅ...     

激光辐照制备搪瓷涂层

激光辐照制备的搪瓷涂层表面粗糙,与金属基材结合牢固。一般由 Si,Al,Na,K,B,F,O等元素组成。在激光辐照过程中 K,Na 明显地挥发,从而在涂层中的含量明显减少;Co,Ni,主要分布在界面附近;Fe 元素也由基材进入涂层,呈梯度状分布,在界面过渡区含量很高,在涂层内含量很低。搪瓷涂层的形成与激光辐照参数,特别与激光功率间存在极为密切的关系;只有选用合理的参数,才能制得搪瓷涂层。     

熔融 NaCl-(Na,K)_2SO_4引起的 Fe-Cr 合金的热腐蚀

本文采用电化学方法研究了 Fe-Cr 合金在800℃、熔融 NaCl-(Na,K)_2SO_4中的腐蚀行为,并对腐蚀产物进行了观察和分析。结果表明,提高合金 Cr 含量可以改善合金耐蚀性能。氧化-硫化是Fe5Cr、Fe10Cr 合金腐蚀破坏的主要方式;氧化膜的熔融反应是 Fe20Cr、Fe25Cr 合金加速腐蚀的主要原因。同时,氧化膜的机械破裂也加速了合金的腐蚀。     

A3钢的工业大气腐蚀

在辽宁省工业城市进行 A3钢大气暴露试验。两年后测出不同地点腐蚀率。依据所记录的各试验点的气象数据和污染数据,讨论了 A3钢的大气腐蚀规律。     

3DFD Simulation of Asymmetric Wave Field by Side-wall Acoustic Tool in Open and Cased Wells

1. Introduction Side-wall acoustic logging tools, such as the Segmented Bond Tool (SBT) from Baker Atlas and the tools for open hole measurements, utilize acoustic transducers mounted on six pads to make compensated acoustic velocity and attenuation measurements which are not affected by mud weight, gas cut, fast formation effects, casing surface conditions or reasonable tool de- centralizing. Studies on the wave fields generated by these tools are very important to tool design and data int…     

Ti_3Al金属间化合物的熔盐热腐蚀

采用电化学方法并结合扫描电镜、X 射线衍射、电子探针和能谱等物相分析技术研究了 Ti_3Al 金属间化合物在800℃熔融 NaCl-(Na,K)_2SO_4体系中的腐蚀行为。结果表明,Ti_3Al 合金耐熔盐腐蚀性能远低于 Ni 基 IN738合金。腐蚀时在合金表面形成外层为 TiO_2;内层为富 Nb 的Nb_2O_5,Al_2O_3,TiO_2的混合层和中间层为富 Al 的 TiO_2,Al_2O_3混合层的多层腐蚀层结构。Ti 快速向外扩散和氧向内扩散使合金表面腐蚀产物层迅速增厚。腐蚀产物内层的富 Nb 氧化物破坏了膜层与合金基体的粘附性。     

Preparation and Characterization of Zeolite Beta with Low SiO_2/Al_2O_3 Ratio

Zeolite beta with a low SiO2/Al2O3 ratio was synthesized by a novel two-step process.The synthesized sample was characterized with XRD,SEM,FTIR,and N2 adsorption-desorption and solid-state MAS NMR.The results showed that aluminium species were inserted into the framework of zeolite beta.The BET surface area,volume,and particle size of the zeolite beta sample decreased with decreasing SiO2/Al2O3 ratio.Our process was proved an efficient route to synthesize zeolite beta with a low SiO2/Al2O3 ratio.     

Ti_3Al PHASE PRECIPITATION DURING VIBRATION FATIGUING FOR A TITANIUM ALLOY

Ｔｉ_３ＡｌＰＨＡＳＥＰＲＥＣＩＰＩＴＡＴＩＯＮＤＵＲＩＮＧＶＩＢＲＡＴＩＯＮＦＡＴＩＧＵＩＮＧＦＯＲＡＴＩＴＡＮＩＵＭＡＬＬＯＹ￥ＴａｏＣｈｕｎｈｕ；ＺｈａｎｇＳｈａｏｑｉｎｇ；ＹａｎＭｉｎｇｇａｏ（ＩｎｓｔｉｔｕｔｅｏｆＡｅｒｏｎａｕｔｉｃａｌＭ?..     

Deterministic learning of completely resonant nonlinear wave systems with Dirichlet boundary conditions

In this paper, we investigate the approximation of completely resonant nonlinear wave systems via deterministic learning. The plants are distributed parameter systems (DPS) describing homogeneous and isotropic elastic vibrating strings with fixed endpoints. The purpose of the paper is to approximate the infinite-dimensional dynamics, rather than the parameters of the wave systems. To solve the problem, the wave systems are first transformed into finite-dimensional dynamical systems described by ordinary differential equation (ODE). The properties of the finite-dimensional systems, including the convergence of the solution, as well as the dominance of partial system dynamics according to point-wise measurements, are analyzed. Based on the properties, second, by using the deterministic learning algorithm, an approximately accurate neural network (NN) approximation of the the finite-dimensional system dynamics is achieved in a local region along the recurrent trajectories. Simulation studies are included to demonstrate the effectiveness of the proposed approach.