波普倾向的新城市主义

尽管原本相互对立？现代主义的乌托邦城市理想和后现代主义的历史主义倾向所产生的城市中心贵族化的现象有着同一个推动力——精英主义.同时精英主义使得城市不断同质化，而在当今全球化大趋势下。大众自我意识的觉醒渴求一个更加人文和包容的城市？一种新的城市主义以一种波普的面貌出现.表现出了当代城市的大众化．偶发性和捞贴的特质.     

昌房500kV紧凑型输电线路中的关键技术

昌平一房山500kV紧凑型输电线路已于1999年11月投入运行，该线路摒弃了常规的布置形式，将三相导线以等边倒三角形形式排列在同一塔窗内。每相导线采用六分裂形式，任意两相导线间的中心距为6．7m，因此，与常规线路相比，紧凑型线路走廊的占地宽度减少了17．9m。紧凑型线路的自然功率为1．34GW，比常规线路高34％，并已通过1．6GW大负荷试验。地面电场强度超过4kV／m的宽度为16m，较常规线路减少32m，从而减轻了电磁污染。此外，紧凑型线路可进行带电作业。     

采用Massive MIMO进行5G覆盖试点规划

本文对5G试点背景及相关技术进行介绍,通过频谱资源分析,确定采用3.5 GHz作为5G试点的主要频段;通过不同信道的链路预算分析,发现采用64T64R的Massive MIMO设备进行5G组网的站址需求与现有4GD频段组网相当;选定连续覆盖试点区域后,综合考虑试点区域特性及现有资源配置,最终形成试点区5G连续覆盖异构组网方案,并采用仿真技术对试点后的效果进行预估,在此基础上,对5G试点采用的新技术Massive MIMO效果进行验证,得出采用64T64R设备的小区容量是当前4G站点的3～4倍的结论,为新技术应用推广奠定基础,也为后续5G商用总结规划建设经验.     

Efficient compressive sensing based sparse channel estimation for 5G massive MIMO systems

Massive MIMO (multiple-input-multiple-output) is one of the key technologies of 5G mobile cellular networks, which can form a huge antenna array by providing a large number of antennas at the cell base station. It will greatly improve the channel capacity and spectrum utilization and has become a hotspot in the field of wireless communications in recent years. Aiming at the high complexity of channel estimation algorithm for massive MIMO system, a sparse channel estimation algorithm with low complexity is proposed based on the inherent sparsity of wireless communication channel. The algorithm separates the channel taps from the noise space on the basis of the traditional discrete Fourier transform (DFT) channel estimation, so that the channel estimation only needs to calculate the part of the channel tap, so the computational complexity of the algorithm is greatly reduced. The simulation results show that the proposed algorithm can achieve near minimum mean square error (MMSE) performance while maintaining low complexity. Moreover, the Bit Error Rate and Inter-Cell Interference also indicates that the proposed improved algorithm shows better overall performance than the conventional algorithms which makes it suitable from practical perspective.     

合成孔径雷达成像处理的并行实现方法

本文提出了一种实现合成孔径雷达（SAR）成像处理的并行距离／多普勒算法，该算法能有效地提高SAR的成像处理速度，是实现SAR实时成像处理的有效途径，该算法尤其适合于超级并行机（MPP）及工作站和微机构成的群机系统进行并行计算。实验结果表明该并行算法能有效地减少SAR成像处理的运算时间。最后给出了原始数据的成像结果。     

基于高职专业课教学的慕课建设与应用

慕课是当前信息化技术应用到专业课课程改革中的重要体现,而在慕课建设的过程中,各级院校、不同类别的 任课教师对慕课的理解和应用却不尽相同。笔者从高职学院专业课的教学实际出发,结合高职院校慕课平台搭建和慕课教学 设计,讨论如何有效开展高职专业课的慕课建设与应用。     

FIRE,a novel concept of massive gas injection for disruption mitigation in ITER: Validation on Tore Supra

Disruptions in large size tokamak like ITER must be mitigated to reduce detrimental effects on the device. Massive impurity injection prior to disruption is a promising mitigation technique. Many injector designs have already been tested on nowadays tokamaks. A novel concept of injector has been designed and tested on Tore Supra. It is based on the use of high pressure cartridges sealed with a bursting disc. For firing, an electric arc is generated inside the cartridge close to the rupture disc. This initiates a shock wave which breaks the disc. Tests show that the opening is achieved in less than 400 μs. A detailed modeling of the fast injector operation is presented. One result is that the gas is expelled in about 2 ms and an outflow rate as large as 4.2 × 10²⁵ atoms/s can be achieved at the nozzle exit (1 cm diameter). Massive neon gas injections have be performed on stable plasma to validate the concept. The gas penetration into the plasma prior to disruption is followed by a fast camera. Comparison with a ferromagnetic-valve based injector was also carried out. It is found that the velocity of the cold front penetration into the hot plasma is larger using this new injector.     

A survey on 5G massive MIMO localization

Massive antenna arrays can be used to meet the requirements of 5G, by exploiting different spatial signatures of users. This same property can also be harnessed to determine the locations of those users. In order to perform massive MIMO localization, refined channel estimation routines and localization methods have been developed. This paper provides a brief overview of this emerging field.     

矿山系统空间数据仓库建设初探

分析了矿山系统传统数据存储特点,认为传统数据库已无法满足矿山管理应用需求,数字矿山的建设急需建立一个方便存储和提取的工具。矿山数据大多为空间数据,因此,空间数据仓库的建立能解决矿山数据的收集和存储问题,实现多源数据的管理和分享,为决策部门提供详实而准确的数据。