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Construction of a sequence of approximate solutions for determining the cumulative energy associated with the convergence of a l


Distribution pattern of apparent stress seems to have a largescale correlation with the cumulative energy release level in the 20th century.


The set of input data for quantification was based on SPET acquisition of emission data in four separate energy windows, the associated cumulative energy spectra and transmission data.


Data on respiration and energy content were used to estimate the cumulative energy investment by workers per queen and male of Lasius niger from small larvae (>amp;lt;0.3 mg) to flying adults.


The AE parameters like acoustic rate or cumulative energy are highly sensitive to fabric arrangement in rocks with pronounced fabric (e.g.

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 In this paper the role of summation in classical Cowell's method is discussed. It is not only proved that the secondsum formula is algebraically equivalent to the formula in which no summation is employed,but also that contrary to the tradi tional view such algorithm cannot efficiently reduce the accumulation of roundoff error.Therefore,the secondsum formula hardly has any advantage.But when the firstsum formula is used,the accumulated roundoff error is about O(h) times that of primary formulas,in which... In this paper the role of summation in classical Cowell's method is discussed. It is not only proved that the secondsum formula is algebraically equivalent to the formula in which no summation is employed,but also that contrary to the tradi tional view such algorithm cannot efficiently reduce the accumulation of roundoff error.Therefore,the secondsum formula hardly has any advantage.But when the firstsum formula is used,the accumulated roundoff error is about O(h) times that of primary formulas,in which h is the step length.Here the value of partial double precision arithmetic is also discussed.This arithmetic might reduce the accumulated roundoff error which is about O(h~2) times that of primary arithmetic,but in this case there is not any advantage to use the firstsum or secondsum formula.  本文讨论了经典的 Cowell 方法中和分技术的作用.证明了采用二次和分的方法不仅在代数上完全等价于不用和分的方法,而且与传统的观念相反,这样的算法并不能有效地减少舍入误差的累积,因而,使用二次和分的方法几乎没有优越性.但若采用一次求和的方法,舍入误差的累积能改善 O(h)倍(h 为积分步长).本文亦讨论了部分双倍位算法的作用,它能使舍入误差的累积改善 O(h~2)倍,但此时采用二次、一次和分都没有任何好处.  Objective: To introduce cumulative metaanalysis method and its characteristics in analysis. Methods: 3 ways of accumulation were used to analyze real examples and illustrate with graphs. Results: The time when the significant effectiveness of treatment appears first can be confirmed, and the confidence intervals of treatment effectiveness of total population can be narrowed by accumulation in chronological order. The impact of sample size on the comprehensive results can be observed by accumulation according... Objective: To introduce cumulative metaanalysis method and its characteristics in analysis. Methods: 3 ways of accumulation were used to analyze real examples and illustrate with graphs. Results: The time when the significant effectiveness of treatment appears first can be confirmed, and the confidence intervals of treatment effectiveness of total population can be narrowed by accumulation in chronological order. The impact of sample size on the comprehensive results can be observed by accumulation according the sample size. With the entering of small difference group the estimated value of comprehensive results tended to be small can observed accumulative according to the difference between treatment and control groups. Conclusion: Cumulative metaanalysis method can provide more information than traditional metaanalysis method. It can't be substituted by traditional method. However, it is affected by publication bias.  目的 介绍累积Meta分析方法及其分析特点。方法 采用3种累计方式进行实例分析并辅以图例说明。结果 按研究年代顺序累积能证实疗效最初具有统计学意义的时间,及大型实验缩窄了估计总体治疗效应值可信区间的长度;按样本大小顺序积累能观察到样本大小对综合结果的影响;按治疗组和对照组疗效差异的大小(AR)累积能观察到随着疗效差异较小研究的加入,综合结果的估计值呈现减小的趋势。结论 累积Meta分析方法较传统Meta分析方法提供更多有价值的信息,是传统Meta分析方法不能取代的方法,但该方法仍然受到发表偏倚的影响。  There are a number of high altitude nuclear electromagnetic pulse (HEMP) waveform standards for equipment and systems on susceptibility to the testing effects. These typical HEMP standards include IEC6100029, MILSTD461E and some other publication standards such as Bell Laboratory's etc. The time domain parameters, amplitude spectrum, and the cumulative energy fluence of these HEMP waveforms are compared in this paper. The results show that earlytime HEMP in IEC6100029(equals to MILSTD461E) is less severe... There are a number of high altitude nuclear electromagnetic pulse (HEMP) waveform standards for equipment and systems on susceptibility to the testing effects. These typical HEMP standards include IEC6100029, MILSTD461E and some other publication standards such as Bell Laboratory's etc. The time domain parameters, amplitude spectrum, and the cumulative energy fluence of these HEMP waveforms are compared in this paper. The results show that earlytime HEMP in IEC6100029(equals to MILSTD461E) is less severe than HEMP in the 'publication 1976' and Bell laboratory standard except for slots coupling as the former have slightly shorter rise time and more wide 3dB bandwidth. In the end, the influence on the HEMP simulation and effects due to the change of HEMP standard are also discussed in this paper.  目前,国际上已有美军标、国际电工委员会、Bell实验室及各种学术出版物等各种高空核爆电磁脉冲波形标准。综述了这些标准,并从时域参数、频谱、归一化累积能流谱、总的能量密度等几方面研究其异同性。比较后认为,IEC61000 2 9和MIL STD 461E表述的新标准要比1976年出版物波形和Bell实验室波形的频谱范围宽,对电子系统的小孔缝耦合效应稍强,但对多数效应物尤其是线缆引入的传导耦合,损伤程度则相对弱化。最后,分析了由于HEMP波形表述形式变化,给EMP模拟器和效应研究带来的影响和新动态趋势。   << 更多相关文摘 
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