海上高分辨率地震采集

重点介绍海上高分辨率地震采集对空气枪震源、记录仪器和电缆的基本要求.     

Fix7.0在张钢5#高炉自动控制系统中的应用

张钢5#高炉微机自动控制系统,采用Fix7.0组态软件实现系统的数据采集、实时监控、历史数据处理以及安全和报警等功能。生产实践证明,该系统图形界面友好、参数准确可靠、操作方便、安全稳定。     

Estrogen improves response accuracy and attenuates the disruptive effects of Δ?-THC in ovariectomized rats responding under a multiple schedule of repeated acquisition and performance.

Despite evidence of an interaction between cannabinoids and estrogen in the brain, little information is available regarding the consequences of this interaction on behavior. A within-subjects design was used to examine the effects of estrogen and Δ?-tetrahydrocannabinol (Δ?-THC) on learning and memory in ovariectomized rats responding under a multiple schedule of repeated acquisition and performance. Treatment with low physiological levels of estrogen, delivered in Silastic capsules, improved response accuracy without affecting response rate during acquisition. Estrogen also attenuated the ability of Δ?-THC (0.56-3.2 mg/kg) to decrease response accuracy and rate during acquisition and response accuracy during performance. Results indicate that estrogen can improve accuracy during acquisition of a nonspatial operant task and can attenuate Δ?-THC-induced behavioral deficits. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

ARAM—24遥测地震数据采集系统的数传及重采样技术分析

本文对ARAM—24遥测地震数据采集系统有关采集数据、命令、状态数据的传输方式及系统数据传输的编码方式进行了分析,并详尽地阐述了地震数据的重采样技术及实现这一功能的具体方法。     

运用Verilog HDL实现AD7862的数据采集设计

AD7862是AD公司推出的一种高速、低功耗、双12位A/D转换芯片。本文对它的性能进行了简要的介绍,并用verilogHDL设计方法对它在数据采集中的应用进行了设计。     

官1地区高分辨率地震采集技术

官1地区断块发育,勘探潜力较大。老资料分辨率较低,影响了进一步勘探开发。针对工区勘探存在的技术难点,使用小面元、高采样率提高地震资料分辨率;采用小炮排距、高覆盖次数的目标设计提高资料信噪比;根据对干扰波的压制效果优选最佳观测系统;使用延迟叠加震源提高有效波的下传能量;通过多种方法联合调查、解释,量化工区不同井点的激发井深,保证资料采集质量。得到的新资料较老资料分辨率和信噪比明显提高,满足了精细解释的需要。     

Is there "feedback" during visual imagery? Evidence from a specificity of practice paradigm.

The specificity of practice hypothesis predicts the development of a sensorimotor representation specific to the afferent feedback available during skill acquisition (Proteau, 1992; Proteau, Marteniuk, Girouard, & Dugas, 1987). In the present investigation, we used the specificity of practice hypothesis to test whether skill acquisition through visual imagery would lead to the development of a sensory-specific movement representation similar to one resulting from actual practice. To accomplish this objective, participants practiced walking a 12-m linear path in one of three practice conditions, full-vision (FV), no-vision (NV), or visual imagery (VI), for either 10 or 100 trials. Knowledge of spatial and/or temporal results (KR) was provided to participants following each trial during this phase. Following acquisition, participants completed 10 NV trials without KR. An analysis of root-mean-squared-error (RMSE) indicated NV participants were more accurate than both FV and VI participants in the transfer condition. We believe the equivalence in transfer RMSE between FV and VI suggests that there are similarities between the movement representations attained by FV and VI practice. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A Rapid Code Acquisition Scheme for DS/SS Systems

In this paper, we propose a rapid code acquisition scheme for direct-sequence spread-spectrum (DS/SS) system basing on the improved seed accumulation of sequential estimation (ISASE). This method solves the problem that SASE scheme cannot work in the presence of carrier-frequency offset. The mean acquisition time of the ISASE scheme is derived by the generating function flow graph technique, and the tolerance of carrier-frequency offset is obtained in a closed-form expression. The performance of the proposed acquisition scheme is analytically evaluated in terms of the mean acquisition time. Analysis in theory and numerical results show that the proposed scheme yields improvement of the mean acquisition time over the RASE scheme by a factor of 2–15 times for the PN} period more than 255 in normal operating condition. For the important parameter-accumulating number m, we recommend to choose from 5 to 20 through the tradeoff of the tolerance of carrier-frequency offset and acquisition speed. Jiachi Wang was born in September, 1971. He is a Phd candidate in department Electronics and Information Engineering, Huazhong University of Science and Technology. His research areas include spread spectrum and digital communication, and digital signal processing. Xiulin Hu was born in 1945. He is a professor and Phd advisor in department Electronics and Information Engineering, Huazhong University of Science and Technology. His research areas include spread spectrum and digital communication. Yunyu Zhang was born in 1948. She is a professor in department Electronics and Information Engineering, Huazhong University of Science and Technology. Her research areas include software radio and digital communication. Qingyun Dai was born in 1977. She is a Phd candidate in department of Electronics and Information Engineering, Huazhong University of Science and Technology. Her research areas is wireless network.     

OFDM系统中一种高效的符号定时估计算法

本文提出了一种新的适合于OFDM系统的符号定时估计算法。该算法利用经过特殊处理的前后两段信息序列的内在相关性进行准确的符号定时估计。理论分析和仿真表明,该算法能在大频偏低信噪比的条件下完成定时捕获的任务,并且无需专门的训练符号,从而大大提高了系统传输的效率。     

基于CompactPCI总线的雷达信号采集系统及其设备驱动程序设计

首先给出一种基于CompactPCI总线的雷达信号采集系统体系结构和硬件设计,然后介绍针对这类数据采集电路的设备驱动程序的设计方法,着重讨论硬件访问、中断处理、DMA传输以及驱动程序和应用程序间的相互通信等4个方面的问题,并给出相应的解决方案。