基于数据挖掘的电力云资源规划调度

随着虚拟化技术的应用,数据中心的资源利用率已经得到一定程度的提高,但是云资源通常还是根据用户提出的需求预先分配,资源利用率仍然有待提高.为了进一步改进资源利用率,云中心的实际资源需求可分为“周期资源”及“峰期资源”.“周期资源”可以通过历史规律,利用递阶成分负载模型进行分析,预测出数据中心大部分时间的资源需求;“峰期资源”主要是满足短时间内的各种高峰资源需求,这种需求应用了排队论及随机均衡算法模型并根据实际应用的需要动态启用、分配和收回资源.通过使用资源收集与分配守护进程对云中心资源需求进行规划调度实验,效果明显,从而为云中心资源利用率的提升及节能减排提供了一种有效途径.     

4G移动通信系统的热点技术及其发展动态

简述了4G系统的特点,并介绍了4G中的OFDM、软件无线电、智能天线、IPv6等新技术,依靠这些复杂的技术,4G系统得以实现100Mbps的传输速度,为人们提供高质量的数据服务。文章最后指出了4G未来的发展动态。     

单场限环结构的表面电场分布及环间距的优化

基于横向扩散与纵向扩散构成的冶金结边界为椭圆形这一特点,讨论单场限环结构表面电场强度的分布,给出表面电场强度、主结及环结分担电压的解析表达式。在纵向结深和掺杂浓度一定的条件下,根据临界电场击穿理论,讨论环间距的优化设计方法。单场限环结构主结环结间表面电场强度的绝对值曲线近似呈抛物线,最大电场位于主结处。随着环间距的增大,最大电场变大;随着横向扩散深度的增大,最大电场变小。环右侧最大电场也出现在结处,随着环间距和横向扩散深度的增加,最大电场均减小。在场限环结构中,当主结和环结在表面处的最大电场强度均等于临界电场强度时,击穿电压达到最大值,此时所对应的环间距为最佳环间距。     

Two‐Dimensional Assembly of Symmetric Colloidal Dimers under Electric Fields

Like atoms and molecules with directional interactions, anisotropic particles could potentially assemble into a much wider range of crystalline arrays and meso‐structures than spherical particles with isotropic interactions. In this paper, the electric‐field directed assembly of geometrically anisotropic particles–colloidal dimers is studied. Rich phase behavior and different assembly regimes are found, primarily arising from the broken radial symmetry in particles. The orientations of individual dimers depend on the frequency of the electric field, the ramping direction of frequency, and the salt concentration. The competition and balance between the hydrodynamic, electric, and Brownian torques determine the orientation of individual particles, while the competition between the electrohydrodynamic force and dipolar interaction determines the aggregation of aligned particles at a given experimental condition. The field distribution near the electrode is critical to understand the orientation and assembly behavior of colloidal dimers on a conducting substrate. This study also demonstrates the effectiveness, the reversibility, and potential opportunity of applying electric field to control the orientation and direct the assembly of non‐spherical particles. In particular, two dimensional close‐packed crystals of perpendicularly aligned dimers are obtained, which shows promise in fabricating 3D photonic crystals based on dimer‐like colloids and field‐directed display.     

Joint frequency and DOA estimation using spatial-temporal co-prime sampling with off-grid sources

A method of joint frequency and direction of arrival (DOA) estimation using spatial-temporal co-prime sam-pling with off-grid sources was proposed to solve the problem of two-dimensional (2D) mismatches of signals.Firstly,the received signal was sampled by spatio-temporal co-prime sampling technique to construct 2D sparse reconstruction model with the filled coarray.Then the frequency mismatch term and angle mismatch term were incorporated into the re-ceived data model.Based on the above modified model,an improved greedy algorithm was presented to obtain the fre-quency mismatch and angle mismatch by estimating the spectrum leakage terms jointly.So the 2D off-grid sources can be corrected to accurate positions.The method can increase the degrees of freedom (DOF) in the space-frequency domain.Moreover,the method has reduced the amount of computation,and it can improve the frequency and DOA estimation accuracy in the meantime.Simulation results demonstrate the correctness and effectiveness of the proposed approach.     

Kirigami/Origami‐Based Soft Deployable Reflector for Optical Beam Steering

The beam steering mechanism has been a key element for various applications ranging from sensing and imaging to solar tracking systems. However, conventional beam steering systems are bulky and complex and present significant challenges for scaling up. This work introduces the use of soft deployable reflectors combining a soft deployable structure with simple kirigami/origami reflective films. This structure can be used as a macroscale beam steering mechanism that is both simple and compact. This work first develops a soft deployable structure that is easily scalable by patterning of soft linear actuators. This soft deployable structure is capable of increasing its height several folds by expanding in a continuous and controllable manner, which can be used as a frame to deform the linearly stretchable kirigami/origami structures integrated into the structure. Experiments on the reflective capability of the reflectors are conducted and show a good fit to the modeling results. The proposed principles for deployment and for beam steering can be used to realize novel active beam steering devices, highlighting the use of soft robotic principles to produce scalable morphing structures.     

智能语音机顶盒的软硬件实现方案

在语音交互技术发展的大背景下,智能音箱产品在提供内容娱乐、生活服务的同时,更多地接入家庭生活场景中,成为智能家居的控制中心。从智慧家庭下最新的业务需求出发,详细分析为了适应新的业务需求和智能语音机顶盒需增加的功能要求,提出了满足新业务功能的智能语音机顶盒的软硬件实现方案。     

智慧城市及其评价指标和评估方法研究

结合业界现有智慧城市研究和我国城市的特点,提出了智慧城市的定义。对国内外智慧城市的发展现状和特点进行了分析和对照。研究了智慧城市评价指标和评估方法,提出了一套科学化、可定制、易剪裁的评估指标体系,可以满足不同规模（大、中、小）、不同特色（综合型、工业型、旅游型、港口型等）的智慧城市评估需求。     

智能型漏电断路器的设计

叙述了剩余电流产生的原因及危害,设计了一套智能型漏电断路器,并给出了硬件结构和软件设计。试验结果表明:该智能断路器质量可靠、性能稳定、完全达到了国家标准的要求。     

动态关断资源栅格的异构无线网络基站节能算法

针对现有的基于载频/时隙关断的基站节能算法没有考虑异构网络之间的协同或者只考虑单一的业务与实际网络情况不相适应的问题,在异构网络环境下提出了动态关断资源栅格(RG,resource grid)的基站节能新算法——DRGSM(dynamic resource grid shut mode)算法。该算法根据网络的即时负载,当有业务接入时,动态打开RG以满足业务的QoS要求;当RG闲置时,即将其关断以实现节能。仿真结果表明,所提算法较现有的基于载频/时隙关断的基站节能算法,明显地降低了能耗,提高了节能百分比。