基于SOA的山东省地籍管理信息系统设计与实现

文章提出了基于SOA的地籍管理信息系统建设的目标和建设原则.以山东省地籍管理信息系统为例,给出了基于SOA的地籍管理信息系统的应用框架结构设计和实现,并对基于SOA的山东省地籍管理信息系统建设的关键技术和系统特色进行了总结.     

化学成分对ASTMA890双相不锈钢组织的影响

研究化学成分对ASTM A890双相不锈钢组织的影响,利用金相显微镜对试样进行组织观察,结合体视学定量金相,利用最小二乘法对所测得数据进行拟合,建立双相不锈钢的组织及相比例与化学成分之间的直接联系。结果表明:铬当量Creq=26.68%、镍当量Nieq=11.89%时,可使双相不锈钢的相比例达到理想的1∶1,从而获得良好的综合性能。     

EA4T钢冷却过程中脉冲电流对组织与性能的影响

针对EA4T钢车轴淬火过程中心部会析出大量大尺寸先共析铁素体的问题,采用脉冲电流辅助加热方法,研究冷却过程中脉冲电流与先共析铁素体析出的关系。EA4T钢试样加热至900℃保温20min后,以25℃/min冷速冷却,并在冷却过程中通入一定参数的脉冲电流。结果表明,由于脉冲电流辅助加热的热效应,推迟了相变过程中先共析铁素体在奥氏体晶界处的析出。与未通脉冲电流的试样相比,先共析铁素体的含量降低,尺寸减小,试样的强度、伸长率及冲击值有所提高。     

纳米Mn-Zn铁氧体制备过程中的元素补偿研究

采用回流制备方法,通过对比实验和化学定量分析,研究了Fe2+的催化作用以及对Mn、Zn元素实施补偿的可行性,得出试样中金属元素的摩尔比。实验发现:pH≤9.6时,Fe2+对合成反应具有明显的催化作用。初始pH>7时,Zn元素能进行补偿;初始pH>8.5时,Mn元素才能进行补偿。XRD和TEM研究表明,Mn-Zn铁氧体纳米粒子为球形,平均粒径约为4.35nm。     

基于MapReduce的海量图像处理模型的研究

针对目前图像的格式和数量都在不断增加,传统的串行处理方法无法满足海量的图像数据处理的问题,提出一种基于MapReduce并行框架的海量图像数据处理模型.模型中取消了Reduce处理函数,在Map函数处理完成后直接输出处理结果,不仅避免了Reduce函数和Re-duce任务处理所需的时间,同时减少了Map与Reduce阶段之间操作所消耗的时间.实验基于Hadoop伪分布式云平台,实现了文中提出的并行处理模型.     

Joint beam selection and user association strategy for beam space millimetre wave downlink systems

Beam space multiple‐input multiple‐output (B‐MIMO) systems operating at mmWave frequency in downlink uses different beam selection techniques for reducing the required number of radio frequency chains without apparent performance loss. In this paper, a joint beam selection and user association scheme with the objective of sum rate maximization is proposed. The proposed work on beam selection is based on a norm and uncorrrelation based approach, which considers channel correlation among the users so as to avoid inter‐user interference. Two different methods for beam user association with one modelled as a balanced assignment problem based on average sum assignment method and the other method that associates an optimal beam to every user by considering their channel gain values are also proposed along with beam selection. The proposed beam assignment methods are less complex and efficient in finding a suitable beam to every user within the cell. Simulation results show that the proposed method accomplish comparable performance in terms of sum rate and energy efficiency with appreciably low computational complexity relative to the existing methods in a correlated environment.     

Ni基合金+WC激光熔覆层再加热时的显微组织变化特性

采用Ni基自熔合金+块状WC混合粉末进行送粉激光熔覆并获得熔覆层,对熔覆层在不同温度下加热后空冷至室温,观察相应熔覆层的显微组织变化,结果表明：Ni基自熔合金+WC送粉激光熔覆层不适合在500℃～900℃再加热处理,再此温度区间对熔覆层再加热会导致块状WC出现裂纹。Ni基自熔合金基体的显微组织在700℃以上开始不稳定,发生形态和显微组织结构的变化。熔覆层中的块状WC加热至900℃以上时裂纹会被自行焊合,温度继续升高,块状WC会发生离散,分化成细小的WC颗粒,产生这种现象的根本原因是块状WC具有先天的超细纤维、颗粒混合结构。     

Performance analysis of large-scale MIMO system for wireless backhaul network

In this paper, we present a performance analysis of large-scale multi-input multi-output (MIMO) systems for wireless backhaul networks. We focus on fully connected N nodes in a wireless meshed and multi-hop network topology. We also consider a large number of antennas at both the receiver and transmitter. We investigate the transmission schemes to support fully connected N nodes for half-duplex and full-duplex transmission, analyze the achievable ergodic sum rate among N nodes, and propose a closed-form expression of the achievable ergodic sum rate for each scheme. Furthermore, we present numerical evaluation results and compare the resuts with closed-form expressions.     

Compressive sensing power control for interference management in D2D underlaid massive MIMO systems

This paper introduces a sparsity controlled multiple random access scheme for efficient user scheduling in Device-to-Device (D2D) underlaid massive MIMO systems. In order to both avoid collision and enhance the Energy Efficiency (EE) of two-tier Heterogeneous Cellular Networks (HCNs), a unified Compressed Sensing (CS) based interference management strategy is proposed which guarantees concurrent cellular and D2D multi-user transmissions without collision. Specifically, supposing the natural sparsity in practical fifth generation (5G) scenarios and employing the sparse signal processing techniques, an analytical random access based model is adopted where provides several user scheduling and channel gain constraints to permit user identification, channel estimation and data decoding simultaneously. Furthermore, by developing a tractable tradeoff between the total power consumption and overall throughput of D2D tier, the transmission power is optimized such that the EE of D2D tier is maximized. Numerical simulations demonstrate the effectiveness of suggested approach to improve the collision avoidance capability and EE of D2D underlaid massive MIMO systems, even for crowded scenarios where the sparsity constraint does not meet sufficiently.     

物联网海量异构数据存储与共享策略研究

随着物联网向各行业的深入发展,各行业的信息化进程也进入了快车道.信息服务作为物联网在各行业应用中重要的公共服务之一,一直受到广泛关注.然而,当前物联网信息服务系统面对物联网海量异构数据存在性能低下、共享困难等问题.因此,本文提出了一种基于NoSQL、REST以及国家物联网标识管理公共服务平台(NIOT)的存储与共享策略,并着重对该系统的构成、逻辑设计进行了详尽阐述.针对性能改进的策略设计了适当的量化评测,实验结果表明提出策略具有较好的效果,基于实验结果对进一步的优化进行了讨论.