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91.
92.
Prabhat K. Gupta C. Sharma Sumana Bhattacharya A.P. Mitra 《Nutrient Cycling in Agroecosystems》2002,64(1-2):19-31
A comprehensive scientific assessment of CH4 budget estimation for Indian rice paddies, based on a decade of measurements in India, is presented. Indian paddy cultivation areas contain soils that have low to medium levels of soil organic carbon. The average seasonally integrated CH4 flux (E
sif) values calculated from these measurements were 15.3 ± 2.6 g m–2 for continuously flooded (CF), 6.9 ± 4.3 g m–2 for intermittently flooded (IF) single aeration (SA) and 2.2 ± 1.5 g m–2 for IF multiple aeration (MA) rice ecosystems. For CF and IF (MA) rice ecosystems having high soil organic carbon, without organic amendments, the CH4 flux (E
sif) may be increased by 1.7 times relative to low soil organic carbon, whereas it may enhance by 5.3 for CF if amended organically. Organic amendment and high soil organic carbon paddy areas do not alter the methane budget estimates for India (3.6±1.4 TgY–1) much, due to their small paddy harvested area. Methane estimated using average emission factors (E
sif) for all paddy water regimes, which include harvested areas having soils with high organic carbon and organic amendments, may give a budget of 5 TgY–1 for India. 相似文献
93.
Nader Ebrahimi 《Sequential Analysis》2013,32(3):213-227
Exact reliability analysis for complex repairable systems are usually difficult because of the complicated failure process that can result from repair policy. A common approach in practice is to use a simplified process such as the Power Law process which, although not exact, yields useful practical results. In this paper we consider the problem of determining a stopping time when estimating parameters of a Power Law process. The Bayes method is used in order to obtain an optimal time. 相似文献
94.
矢量图形智能判断技术的研究与应用 总被引:1,自引:0,他引:1
研究矢量图形识别是建立工程制图自动阅卷与计算机辅助教学系统的基础。由于组成二维矢量图形图元类型的多样化及图形整体位置状态的不确定性,增加了矢量图形的识别与判断难度。结合开发的《三视图智能解答》系统,研究其智能识别与判断技术。系统中引入三视图导航技术,解决了图形整体定位与识别问题。实现了对矢量图形图元素信息的分类和提取,能够对所提取的的信息与标准答案进行智能判断与评定。该方法已在AutoCAD2000环境下使用AutoLISP语言编程实现。 相似文献
95.
高速宽带数字化示波器在高扫速工作时,仅能采集信号的少数样点。为了看清信号的全貌和精确测量其参数,必须在每两个样点之间进行插值(波形重构)。通过对信号能量的估计,推导了满足精度条件的SinC抽样内插的有限长选取算法,从数字信号处理的角度,研究了高速采样信号数字内插理论。计算机仿真证实了推导的有效性。 相似文献
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Ming Cen Chengyu Fu Ke Chen Xingfa Liu 《Frontiers of Electrical and Electronic Engineering in China》2009,4(1):88-92
To improve the tracking accuracy and stability of an optic-electronic target tracking system, the concept of generalized synergic
target and an algorithm named error-space estimate method is presented. In this algorithm, the motion of target is described
by guide data and guide errors, and then the maneuver of the target is separated into guide data and guide errors to reduce
the maneuver level. Then state estimate is implemented in target state-space and error-space respectively, and the prediction
data of target position are acquired by synthesizing the filtering data from target state-space according to kinematic model
and the prediction data from errorspace according to guide error model. Differing from typical multi-model method, the kinematic
and guide error models work concurrently rather than switch between models. Experiment results show that the performance of
the algorithm is better than Kalman filter and strong tracking filter at the same maneuver level.
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Translated from Journal of University of Electronic Science and Technology of China, 2007, 36(2): 217–219 [译自: 电子科技大学学报] 相似文献
100.
Single-camera mobile-vision coordinate measurement is one of the primary methods of 3D-coordinate vision measurement, and coded target plays an important role in this system. A multifunctional coded target and its recognition algorithm is developed, which can realize automatic match of feature points, calculation of camera initial exterior orientation and space scale factor constraint in measurement system. The uniqueness and scalability of coding are guaranteed by the rational arrangement of code bits. The... 相似文献