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41.
桥口南--徐集地区三维地震资料连片处理技术   总被引:1,自引:0,他引:1  
针对东濮桥口南—徐集地区三维地震资料的特点及本区块的地质要求,制定处理流程,应用能量均衡、面元均化、三维道内插、三维DMO叠加及三维一步法偏移等技术方法,研究解决因为不同年代、不同方法、不同参数所采集的地震数据在连片处理时存在的问题,精细处理三维连片资料,满足构造解释精度的要求,对进一步落实该区构造和增储上产具有重要的作用。  相似文献   
42.
余庆军  谢胜利 《计算机应用》2003,23(12):94-95,98
为了适应MMS(多媒体短信息业务)的发展,提出了一个基于图像扭曲的变形动画生成机制。该机制不仅能够实时地产生效果新奇、富于戏剧性的GIF动画,而且能够根据不同终端的特点实现图像的自适应处理,从而使在无线网络上传输丰富多彩的图像文件变得更为方便。  相似文献   
43.
Abstract. A procedure for evaluating optimal linear estimates of missing values in the minimum dispersion sense is proposed for stationary symmetric stable processes. Analytical expressions for the estimates are obtained for the autoregressive moving-average process and it is shown that the finite variance setting results are special cases. Cases of one and more than one missing value are considered.  相似文献   
44.
戴松新  陆荣鑑 《电子工程师》2006,32(3):63-64,77
介绍了以PIC16F873单片机为控制核心的汽车组合仪表板控制系统的设计,简述了汽车组合仪表板的基本构成,介绍了汽车组合仪表板控制系统的组成和各部分功能,给出了数据采集处理电路、电源电路等部分硬件电路设计方案,并阐述了一些软件设计算法,如分段插补法和用于平滑指针的软件设计算法等。  相似文献   
45.
An 18-year time series of monthly NOAA-AVHRR Pathfinder Land burned area was analyzed for the region of tropical Africa, from July 1981 to June 1999. The transition period between NOAA-11 and NOAA-14 platforms from July 1993 to June 1995 was not included due to missing and outlier data. Stability of the time series was addressed for the input variables in the burned area algorithm, reflectance and temperature channels.A Seasonal AutoRegressive Integrated Moving-Average (SARIMA) model was developed for forecasting potential burned area. The SARIMA model identified an autoregressive regular term with 1-month lag and an autoregressive 12-month seasonal term with one season (12 months) component. A cross-correlation between Southern Oscillation Index (SOI) and burned area was statistically significant predictor variable in a time series with 20-month lag. Results show that the SARIMA model with this predictor improved both, fitting and forecasting, residual variance, by 4.1% and 5.6%, respectively, thereby, demonstrating potential relationship between SOI and burned area for the study region. Forecasting was estimated by considering only the first 16 years of the monthly burned area in the time series, from July 1981 to June 1997. The prediction for the following 24 months (from July 1997 to June 1999) was within the 95% confidence level indicating that the forecast was a valid characterization of the modeled process.  相似文献   
46.
Two macromodeling techniques using rational bases are investigated to accurately predict the natural frequencies of highly resonant microwave structures. Three methods are proposed and compared to calculate pole‐free solutions to the Thiele continued fraction and vector fitting pole‐residue models of the characteristic equation det[Z(s)]. © 2007 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2007.  相似文献   
47.
This paper evaluated the capacity of SPOT VEGETATION time-series to monitor herbaceous fuel moisture content (FMC) in order to improve fire risk assessment in the savanna ecosystem of Kruger National Park in South Africa. In situ herbaceous FMC data were used to assess the Normalized Difference Vegetation Index (NDVI), Normalized Difference Water Index (NDWI), Vegetation Dryness Index (VDI), Improved VDI (IVDI), and Accumulated Relative NDVI Decrement (ARND) during the dry season. The effect of increasing amounts of dead vegetation on the monitoring capacity of derived indices was studied by sampling mixed live and dead FMC. The IVDI was proposed as an improvement of the VDI to monitor herbaceous FMC during the dry season. The IVDI is derived by replacing NDVI with the integrated Relative Vegetation Index (iRVI), as an approximation of yearly herbaceous biomass, when analyzing the 2-dimensional space with NDWI. It was shown that the iRVI offered more information than the NDVI in combination with NDWI to monitor FMC. The VDI and IVDI exhibited a significant relation to FMC with R2 of 0.25 and 0.73, respectively. The NDWI, however, correlated best with FMC (R2 = 0.75), while the correlation of ARND and FMC was weaker (R2 = 0.60) than that found for NDVI, NDWI, and IVDI. The use of in situ herbaceous FMC consequently indicated that NDWI is appropriate as spatio-temporal information source of herbaceous FMC variation which can be used to optimize fire risk and behavior assessment for fire management in savanna ecosystems.  相似文献   
48.
Tensor interpolation is a key step in the processing algorithms of diffusion tensor imaging (DTI), such as registration and tractography. The diffusion tensor (DT) in biological tissues is assumed to be positive definite. However, the tensor interpolations in most clinical applications have used a Euclidian scheme that does not take this assumption into account. Several Rie-mannian schemes were developed to overcome this limitation. Although each of the Riemannian schemes uses different metrics, they all result in a ‘fixed’ interpolation profile that cannot adapt to a variety of diffusion patterns in biological tissues. In this paper, we propose a DT interpolation scheme to control the interpolation profile, and explore its feasibility in clinical applications. The profile controllability comes from the non-uniform motion of interpolation on the Riemannian geodesic. The interpolation experiment with medical DTI data shows that the profile control improves the interpolation quality by assessing the reconstruction errors with the determinant error, Euclidean norm, and Riemannian norm.  相似文献   
49.
介绍并评述人机界面可用性的定义、可用性测试与评估的指标及方法。学术界对于可用性的内涵已基本达成共识,但大多针对不同界面选取不同的测试与评估指标及权重,测试与评估方法也大都停留于主观评价,还未能深入探讨用户与系统交互过程中的内在心理机制。  相似文献   
50.
针对无线传感器网络链路质量估计模型中回归算法复杂度高、缺少统一分类标准和公开数据集等问题,提出了一种基于EWMA和线性回归的链路质量估计方法ELR-LQE。以物理层获取的RSSI、LQI和SNR,以及包接收率PRR作为度量参数,分别在多种实验环境中采用不同的发射功率、竞争条件和部署方式采集数据,建立了链路质量估计数据集。通过最小值填充和EWMA对数据进行预处理,明显提高了回归模型的输入特征与链路质量的相关性。与现有方法相比,提出方法易于和网络层协议适配,并且复杂度较低,适合在资源有限的无线传感器网络节点中实现。实验结果显示,ELR-LQE具有较高的精度,在多种实验条件下平均的ME为4.6×10-2,R2为0.99。  相似文献   
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