波束形成和解码的联合迭代接收技术

SDMA技术是提高频谱利用率的有效技术，但在判决反馈最小均方波束形成中，在深衰落之后期望用户波束会指向干扰用户,严重影响了波束形成的性能。文中提出在波束形成和信道解码之后，经过编码、交织，重新生成波束形成的参考信号，再进行波束形成，有效克服了深衰落之后的波束指向错误。计算机仿真结果证明了该方法的有效性。     

Spray forming technology for military applications

Over the past five years, the Annapolis Detachment, Carderock Division, Naval Surface Warfare Center (formerly David Taylor Research Center) has established a state- of- the- art spray forming facility for the study and exploitation of this near net shape manufacturing process. Spray forming is a single step gas atomization/deposition process which yields ferrous and nonferrous, near final shape, near fully dense preforms that has proven to be a viable and cost effective alternative to conventional metalworking technology for the production of material preforms with properties surpassing those of their cast and wrought counterparts. Current programs at Carderock Divison Naval Surface Warfare Center are aimed at optimization of the process, certification of the spray formed products and industrialization of the technology.     

高纯锗探测器的快定时性能及其应用

为了将高纯锗（ＨＰＧｅ）探测器用于快定时的物理实验中，本实验研究厂影响高纯锗探测器定时谱仪时间性能的各种因素，找出了获得谱仪最小时间分辨的各种最佳参数。并建立了分辨时间为４．１９ｎｓ，能量分辨率为２０ｋｅＶ，微分非线性好于±２．０％，计效率可承受１２０×１０￣３ｓ￣（－１）的时间微分扰动角关联谱仪。利用此谱仪，以￣（２０４）Ｂｉ为探针核，研究了Ｂｉ系高温超导的微观机理，取得了较好的结果。     

快速Hartley变换在实时相关器中的应用

快速Ｈａｒｔｌｅｙ变换（ＦＨＴ）是离散Ｈａｒｔｌｅｙ变换（ＤＨＴ）的快速算法，它是一种实序的变换，其正反变换具有完全相同的形式。利用ＦＨＴ进行实数据相关可以避免复数运算，特别适用于采和可编程数字信号处理器（ＤＳＰ）来实现的实时相关器。和ＦＦＴ相关算法相比，在保持同样数据吞吐率的情况下，采用ＦＨＴ方法，可显著减少系统所需的高速存贮器，从而，可降低系统的成本。本文讨论了ＤＨＴ的有关性质和ＦＨＴ算法和运     

聚醚砜中空纤维的成形条件对其宏观结构的影响

主要讨论了纺速、填充液压力、凝固浴浓度和拉伸率成形条件的设置对中空纤维的宏观结构的影响 ,为设计具有合理的宏观结构的中空纤维膜提供参考     

Y型密封圈橡胶模设计

介绍了Y型橡胶模具的设计 ,重点对模具结构和模腔尺寸进行了分析和阐述 ,经生产验证 ,此模具结构合理 ,定位可靠 ,操作方便 ,从而为同类产品的设计提供了参考。     

喷射沉积柱状坯形状模型

通过坐标跟踪法建立了沉积坏形状预测模型。该模型不但考虑沉积坯任何表面点身自位置变化对沉积效果的影响，同时考虑了该点温度和其它表面点位置对该点沉积效果的影响，其计算过程严格按照喷射成形的实际过程执行，可实时计算并记录沉积坯的形貌，并验证了计算效果。本文模型可用于多种工艺下喷射沉积坯的形状预测。     

Development of a fast neutron radiography converter using wavelength-shifting fibers

A fluorescent converter for fast neutron radiography (FNR) comprising a scintillator and hydrogen-rich resin has been developed and applied to electronic imaging. The rate of the reaction between fast neutrons and the converter is increased by thickening the converter, but its opaqueness attenuates emitted light photons before they reach its surface. To improve the luminosity of a fluorescent converter for FNR, a novel type of converter was designed in which wavelength-shifting fibers were adopted to transport radiated light to the observation end face. The performance of the converter was compared with that of a polypropylene-based fluorescent converter in an experiment conducted at the fast-neutron-source reactor YAYOI in the University of Tokyo.     

LF6铝合金的超塑性／扩散连接组合工艺试验及理论研究EI

本文研究了ＬＦ６铝合金的超塑性／扩散连接组合工艺，用变形和再结晶的方法细化晶粒，成功地进行了ＳＰＦ／ＤＢ工艺试验，利用电子探针观察了扩散连接接头的界面微观区域，并从机理上分析了金属的超塑性／扩散连接两种工艺之间的内部联系及其金属学行为。     

Ultrahigh-performance FFTs for the CRAY-2 and CRAY Y-MP supercomputers

In this paper a set of techniques for improving the performance of the fast Fourier transform (FFT) algorithm on modern vector-oriented supercomputers is presented. Single-processor FFT implementations based on these techniques are developed for the CRAY-2 and the CRAY Y-MP, and it is shown that they achieve higher performance than previously measured on these machines. The techniques include (1) using gather/scatter operations to maintain optimum length vectors throughout all stages of small-to medium-sized FFTs, (2) using efficient radix-8 and radix-16 inner loops, which allow a large number of vector loads/stores to be overlapped, and (3) prefetching twiddle factors as vectors so that on the CRAY-2 they can later be fetched from local memory in parallel with common memory accesses. Performance results for Fortran implementations using these techniques demonstrate that they are faster than Cray's library FFT routine CFFT2. The actual speedups obtained, which depend on the size of the FFT being computed and the supercomputer being used, range from about 5 to over 300%.