无催化纳米氧化锌的制备及其光学性质研究

本文采用无催化剂直接蒸发高纯Zn粉,在800℃氧气氛条件下,在Si(111)衬底上生长得到以四角状为主的纳米ZnO(T-ZnO)。T-ZnO纳米线每个角约互成110°,长度约为1.5μm,直径100nm左右;Raman分析表明E2(H)普遍存在于各形态的ZnO;光致发光光谱表明,T-ZnO纳米线的光致发光除了与材料性质有关,还与杂质缺陷有关,蓝绿光带是ZnO的缺陷产生的。     

A solar radio moving type IV burst of expanding arches type involving multi-sources

A complex solar radio moving type IV burst was observed on 23 September 1998 with the broadband (1.0–2.0 GHz and 2.6–3.8 GHz) spectrometers with high temporal and spectral resolutions at National Astronomical Observatories of China (NAOC). Comparing to the high spatial resolution data of Siberian Solar Radio Telescope (SSRT), we find that this burst is a rare type of moving type IV burst which is caused by the expanding arches, and the spatial structure oscillations of the radio sources are related with the time structure pulsations of the radio emission. Furthermore, the burst is associated with the multiple quasi-periodic long-term pulsations, and this suggests the existence of multi-scale magnetic structures in a large expanding coronal arch. We think the moving type IV burst is due to the synchrotron emission of the energetic electrons trapped in the expanding arch, and the multiple quasi-periodic pulsations are due to the second harmonic plasma emission.     

Controllable Magnetic Focusing of Cold Atoms on a Chip

We propose a new lens scheme to focus cold atoms by using a controllable inhomogeneous magnetic field from a square current-carrying wire fabricated on a chip. The spatial distributions of the magnetic field are calculated, and the results show that the generated magnetic field is a two-dimensional （2D） quadrupole one and can be used to focus cold atoms or a cold atomic beam. The dynamic processes of cold atoms passing through our square wire layout and its focusing properties are studied by using Monte Carlo simulations. Our study shows that the atomic clouds can be focused effectively by our magnetic lens scheme, and the focal length of the atomic lens and its radius of focused spot can be continuously changed by adjusting the current in the wires.     

硅晶片双面超精密化学机械抛光

为提高硅晶片双面超精密抛光的抛光速率,在分析双抛工艺过程基础上,采用自制大粒径二氧化硅胶体磨料配制了SIMIT8030-Ⅰ型新型纳米抛光液,在双垫双抛机台上进行抛光实验.抛光液、抛光前后厚度、平坦性能及粗糙度通过SEM、ADE-9520型晶片表面测试仪、AFM进行了表征.结果表明:与进口抛光液Nalco2350相比,SIMIT8030-Ⅰ型抛光液不仅提高抛光速率40%(14μm/h vs 10μm/h);而且表面平坦性TTV和TIR得到改善;表面粗糙度由0.4728nm降至0.2874nm,即提高抛光速率同时显著改善了抛光表面平坦性和粗糙度.     

MIMO系统的自适应均衡技术研究

研究了用于MIMO系统的自适应均衡的几种算法，比较了最小均方算法(LMS)、递归最小二乘算法(RLS)、判决反馈算法(DFE)、格型梯度自适应均衡算法(GALE)和格型最小二乘自适应均衡算法(LSALE)。文章的最后给出了仿真结果及结论。     

An Analog Front‐End Circuit for ISO/IEC 14443‐Compatible RFID Interrogators

An analog front‐end circuit for ISO/IEC 14443‐compatible radio frequency identification (RFID) interrogators was designed and fabricated by using a 0.25 µm double‐poly CMOS process. The fabricated chip was operated using a 3.3 Volt single‐voltage supply. The results of this work could be provided as reusable IPs in the form of hard or firm IPs for designing single‐chip ISO/IEC 14443‐compatible RFID interrogators.     

基于复合顺序形态变换的车牌边缘检测

边缘检测是图像分割的重要环节,边缘提取的好坏直接影响了整个图像处理的效果。数学形态学用具有一定形态结构的“结构元素”去度量图像的形态,以解决图像处理和分析问题。文章通过对多种边缘检测方法的分析比较,结合高速公路路口汽车图像噪声大的特点,提出了基于复合顺序形态变换的车牌边缘检测。该方法不但能有效地改善有噪图像边缘检测的效果,鲁棒性好,而且并行快速,便于硬件实现。     

Can Robots Manifest Personality?: An Empirical Test of Personality Recognition,Social Responses,and Social Presence in Human–Robot Interaction

Personality is an essential feature for creating socially interactive robots. Studies on this dimension will facilitate enhanced human–robot interaction (HRI). Using AIBO, a social robotic pet developed by Sony, we examined the issue of personality in HRI. In this gender-balanced 2 (AIBO personality: introvert vs. extrovert) by 2 (participant personality: introvert vs. extrovert) between-subject experiment (N = 48), we found that participants could accurately recognize a robot's personality based on its verbal and nonverbal behaviors. In addition, various complementarity attraction effects were found in HRI. Participants enjoyed interacting with a robot more when the robot's personality was complementary to their own personalities than when the robot's personality was similar to their own personalities. The same complementarity attraction effect was found in participants' evaluation of the robot's intelligence and social attraction. Participants' feelings of social presence during the interaction were a significant mediator for the complementarity attraction effects observed. Practical and theoretical implications of the current study for the design of social robots and the study of HRI were discussed.     

A PIN diode controlled variable attenuator using a 0-dB branch-line coupler

We describe a simple PIN diode controlled variable attenuator that employs a 0-dB branch line directional coupler. The response of the attenuator was measured between 1.3 GHz and 2.6 GHz. At the center frequency, the attenuation monotonically varied from 0.7 dB to 23 dB with the control voltage, and the distributed branch-line coupler structure resulted in low input reflection. Our attenuator is easier to design, smaller in area than a double hybrid coupled attenuator, and has comparable or better reflection and attenuation performance characteristics.     

A comment on 'Stabilization and optimal control for nonlinear systems'

This note presents a counter-example, to demonstrate that thebasis for the proposed solutions to the nonlinear quadraticregulator problem given in the paper ‘Stabilization andoptimal control for nonlinear systems’ is not true ingeneral.