校园文化气氛的创造与延续

通过对邯郸热电厂学校教学综合楼设计的回顾,就中小型建筑在教育建筑中的重要性进行了探讨。     

空间重采样法恒定束宽波束形成器设计

本文视均匀线列阵为连续线阵的均匀离散采样，将宽带方位估计中的空间重采样思想用到恒定束宽波束形成器设计中，并从滤波器设计的观点出发，将阵元权系数等效为空间滤波器的脉冲响应，提出用恢复公式计算不同频率所对应的阵元权系数，从而利用频域波束形成的方法完成恒定束宽波束形成器设计。     

MODE SPACE SMOOTHING ALGORITHM TO ESTIMATE DOA OF COHERENT SIGNALS IMPINGING ON UNIFORM CIRCULAR ARRAY

A novel method to estimate DOA of coherent signals impinging on a uniform circular array( UCA) is presented in this paper. A virtual uniform linear array (VULA) is first derived by using spatial DFT technique, transforming the UCA from element space to phase mode space to obtain the properties of ordinary ULA, and then the well known spatial smoothing technique is applied to the VULA so that the lost rank of covariance matrix due to signal coherence can be retrieved. This method makes it feasible to use the simple MUSIC algorithm to estimate DOA of coherent signals impinging on a UCA without heavy computation burden. Simulation results strongly verify the effectiveness of the algorithm.     

平坦响应空域滤波器和在DOA估计中的应用

本文依据半无穷维二次优化技术提出了一个设计平坦响应空域滤波器（ＳＦ）的新方法，基本思想是使用线性泛函不等式约束夺感兴趣的空域范围内保证ＳＦ响应的平坦性，同时使输出噪声功率最小化，由于使用了硬的线性泛函约束，ＳＦ响应总可以控制在充许的误差范围之内，最后研究了基于平坦响应的信号到达方向（ＤＯＡ）估计问题，计算机模拟结果和分析表明本文提出的基于平坦响应ＳＦ的ＤＯＡ估计性能优于其它有关方法的估计性能。     

WKB近似下的Fourier衍射成象方法

对于介质目标微波衍射成象，本文引入了ＷＫＢ近似来模拟目标内部总场。基于这种近似，我们导出了Ｆｏｕｒｉｅｒ衍射公式，并采用了广义滤波逆传播方法由目标空间谱实现目标特性的重建。计算机模拟结果表明采用ＷＫＢ近似重建目标特性较Ｂｏｒｎ近似有明显改善。     

SPATIAL SPECTRUM ESTIMATION OF COHERENT SOURCES IMPINGING ON NONUNIFORM ARRAYS

The problem of bearing estimation of coherent signal impingiog on an array ofarbitrary geometry is studied.Both approaches are developed,the first one synthesizes theobserved array data into the outputs of a linear uniform array and then processes them viaconventional techniques such as spatial smoothing etc.The second approach is based on theinvariant subspace rotation operation which is equivalent to the translational displacement ofthe artay,linearly independent signal vectors are obtained thereby to span perfectly the signalsubspace.As compared with the conventional processing techniques,the approach based oninvariant subspace rotation does not lead to an effective decrease in aperture size and thereforea decrease in resolution capability.The computer simulations are conducted to demonstrate theeffectiveness of the presented approaches.     

关于出租车载客地点序列推荐技术的研究

在大城市中,出租车已成为实现智能交通运输系统不可或缺的一环。然而,由于一些出租车司机的驾驶经验,和对城市活动的熟悉程度的不足,使得其在寻找乘客时会采取毫无目的的随机漫游策略。这就导致了出租车司机的收益不高,同时也造成了能源的消耗以及环境的污染。针对此问题,将提出出租车载客地点的推荐模型,使得模型给出的推荐地点序列能获得较高的期望收益。具体来说,将基于出租车GPS轨迹数据建立出租车载客地点的马尔科夫决策过程模型,并给出求解该模型的2种算法。仿真实验结果显示,与典型的TopK方法相比,给出的推荐结果能更好地提高单位时间内出租车司机的收益。     

Mimo radar imaging model and algorithm

Based on the array architecture of multiple transmitting/receiving antennas, Multi-Input Multi-Output (MIMO) radar provides a new mechanism for radar imaging technology. In order to explore the processing approach to this imaging mechanism, the two dimensional (2D) imaging model of MIMO radar is established first, and the spatial sampling ability is analyzed from the concept of spatial convolution of the antenna elements. The target spatial spectral filling format of MIMO radar with monochromatic transmitting signal is described. High-resolution imaging capability of MIMO radar is analyzed according to spatial spectral coverage and the corresponding imaging algorithm is presented. Finally, field imaging experiment is used to demonstrate the superior imaging performance of MIMO radar.     

Anticipatory I/O Management for Clustered Flash Translation Layer in NAND Flash Memory

Recently, NAND flash memory has emerged as a next generation storage device because it has several advantages, such as low power consumption, shock resistance, and so on. However, it is necessary to use a flash translation layer (FTL) to intermediate between NAND flash memory and conventional file systems because of the unique hardware characteristics of flash memory. This paper proposes a new clustered FTL (CFTL) that uses clustered hash tables and a two‐level software cache technique. The CFTL can anticipate consecutive addresses from the host because the clustered hash table uses the locality of reference in a large address space. It also adaptively switches logical addresses to physical addresses in the flash memory by using block mapping, page mapping, and a two‐level software cache technique. Furthermore, anticipatory I/O management using continuity counters and a prefetch scheme enables fast address translation. Experimental results show that the proposed address translation mechanism for CFTL provides better performance in address translation and memory space usage than the well‐known NAND FTL (NFTL) and adaptive FTL (AFTL).