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1.
杜健  巩克现  彭华 《通信学报》2015,36(3):202-207
在软输出逐幸存路径处理(SOVA-PSP)算法的基础上,提出了基于Chase译码思想的载波成对复用多址(PCMA)信号的盲分离算法。该算法对SOVA-PSP软输出的结果进行可靠性排序,对于排序中可靠性较低的混合符号进行信号重构,通过重构信号和接收信号之间的欧式距离对比纠正其中的错误结果。仿真结果表明,所提算法与SOVA-PSP算法相比,性能有2 dB左右的增益。  相似文献   
2.
杨勇  张冬玲  彭华  涂世龙 《通信学报》2015,36(4):157-162
针对非合作接收的单通道同频数字调制混合信号,提出一种基于Gibbs采样的分离算法。该算法利用统计的方法获得未知符号序列概率密度的随机样本,运算复杂度随信道阶数的增加不呈指数增长。重点研究了基于单符号对、多符号对的分离算法和信道响应的跟踪,并对Gibbs分离算法和PSP分离算法的性能进行了详细的分析比较。仿真结果表明,针对2路QPSK调制的混合信号,在与L=4时的PSP算法具有近似分离性能的同时,Gibbs分离算法可使复杂度降低近17倍。  相似文献   
3.
Polarized Sensory Positioning (PSP) is a relatively new methodology for sensory characterization, based on the comparison of samples to reference products, usually called poles. The key step in the implementation of this methodology is the selection of the poles. In this context, the aim of the present work was to gain insights on the strategies used by consumers to complete this task and to study the influence of the number and characteristics of the poles on results from PSP. Three consumer studies were carried out, on three product categories: chocolate-flavored milks, vanilla milk desserts and orange-flavored powdered drinks. In each study, three groups of consumers (n = 40) evaluated samples using one of three sets of two or three poles. After the PSP task consumers indicated how they evaluated the degree of difference between the samples and the poles, and listed the sensory characteristics of the poles they took into account for the evaluation. Consumers tended to evaluate the degree of difference between the samples and each of the poles by evaluating the intensity of one or two main sensory characteristics. Sample configurations obtained using two and three poles did not largely differ, especially when the poles clearly represented the sensory characteristics responsible for the main differences among samples. This work demonstrates that it is possible to unfold a multidimensional sensory space with the use of just two well-selected poles, and that the number of poles should be selected considering the main sensory characteristics that discriminate among samples.  相似文献   
4.
提出了一种支持PSP过程的SPEM扩展元模型P-SPEM,并给出了基于P-SPEM的PSP实施过程及支持该过程的原型工具.其中使用PROBE方法帮助个体进行项目计划和估算,用DEA分析方法综合评价工程师的过程性能,有效地指导工程师实施PSP.  相似文献   
5.
研究了网状WDM网中双链路失效下共享通路保护(SPP)和共享链路保护(SLP),以及新的保护方式—共享段保护(SSP)的模型,并分析了静态和动态保护算法。动态保护算法可以根据当前网络状态动态调整链路代价,使它们具有较高的资源利用率和较低的阻塞率。  相似文献   
6.
In ice cream and sorbet manufacturing small ice crystals are desired to deliver a product with a smooth texture and good palatability. This research studied the influence of the operating conditions on the ice crystal size and the draw temperature of the sorbet during the freezing process. The evolution of ice crystal size was tracked with the focused beam reflectance measurement (FBRM) technique, which uses an in situ sensor that makes it possible to monitor online the chord length distribution (CLD) of ice crystals in sorbets containing up to 40% of ice. The refrigerant fluid temperature had the most significant influence on the mean ice crystal chord length, followed by the dasher speed, whereas the mix flow rate had no significant influence. A decrease in the refrigerant fluid temperature led to a reduction in ice crystal size, due to the growth of more small ice crystals left behind on the scraped wall from previous scrapings. Increasing the dasher speed slightly reduced the mean ice crystal chord length, due to the production of new small ice nuclei by secondary nucleation. For a given refrigerant fluid temperature and dasher speed, low mix flow rates resulted in lower draw temperatures, due to the fact that the product remains in contact with the freezer wall longer. High dasher speeds warmed the product slightly, due to the dissipation of frictional energy in the product, the effect of which was in part moderated by the improvement in the heat transfer coefficient between the product and the freezer wall.  相似文献   
7.
涡轮内部流动及冷却射流的湍流特性决定了气膜冷却具有强烈的非定常性,精确获取高时空分辨率的气膜冷却换热特性对揭示其内在机理尤为重要。本文针对气膜冷却的非定常测试需求,聚焦于气膜冷却中涉及的壁面气膜动态覆盖以及叶片表面温度测量,从测量原理、测试系统及实际应用方面依次介绍了两种气膜冷却非定常实验测量技术。基于快响应压敏漆能够测量涡轮叶片、叶身及端壁的非定常气膜冷却,进而利用高温磷光热图评估近发动机工况下高温叶片表面的动态温度分布。  相似文献   
8.
本文阐述了波分复用(WDM)系统进行偏振模散(PMD)补偿的背景和理论基础,首次通过考虑偏振主态(PSP)带宽所能容纳的信道数目提出了两种基于已有单信道补偿方案的满足特定条件的WDM系统中的PMD补偿方案。  相似文献   
9.
基于工作流的软件开发过程支持平台框架   总被引:2,自引:0,他引:2  
讨论了一个软件开发过程支持平台WSDPP的系统框架,这个平台以基于PSAF过程元模型的工作流引擎为核心,以Agent辅助的PSP Client为开发人员与平台的接口.基于这个平台,软件组织的开发过程可以得到全面的自动化控制,不仅RUP/TSP/PSP的嵌套开发过程可以得到有效的支持,而且可以有效地实现TSP中的任务安排以及工作量平衡,完整地收集组织、团队和个人的生产力数据,达到定量管理的目的.在WSDPP平台上执行规范的自动化开发过程,将克服开发过程中的大部分问题,高效率地开发出高质量的软件产品.  相似文献   
10.
A rapid and simple QuEChERS sample treatment was proposed for the development of a selective hydrophilic interaction liquid chromatography-ESI-MS2-based method for the determination of saxitoxins (STXs) in mussel samples. Among different sorbents, ABS Elut-NEXUS phase, composed of polystyrene cross-linked with 50% divinyl benzene and poly(methyl methacrylate), provided the best results. The effects of experimental parameters, including sorbent amount, vortexing time and centrifugation time were investigated and optimized by experimental design. In particular, regression models and desirability functions were applied to find the experimental conditions providing the highest global extraction response. The method was validated under the optimized conditions; detection and quantification limits in the 3–159 μg/kg and 7–436 μg/kg ranges respectively were obtained, except for C2 for which highest values were calculated due to its low ESI ionization efficiency. Finally, the analysis of twenty-eight mussel samples permitted to detect and quantify some of the investigated STXs, proving the applicability of the devised method.  相似文献   
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