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Ultrasound in Obstetrics &Gynecology, Volume 68, Issue 2, Page 256-269, August 2026.ABSTRACT Objectives The primary aims of this study were to validate externally the diagnostic performance of the Assessment of Different NEoplasias in the adneXa (ADNEX) model for distinguishing between malignant and benign adnexal masses, when used by non‐expert ultrasound examiners in general gynecological settings with a low prevalence of ovarian ...
I. M. Dueholm Hjorth +11 more
wiley +1 more source
Gongye shui chuli, 2007 活性污泥数学模型No.1(ASM1)涉及的参数多，而且数学模型是非线性的，求解困难。采用非线性优化的方法仿真ASM1，把仿真结果和基准值做了比较。仿真结果证明非线性优化仿真方法可行。
张英爽 +3 more
doaj +2 more sources
四川大学学报. 自然科学版, 2004 提出了一种将非线性角度电位器用于仿真伺服系统设计的新方案.首先推导了非线性角度电位器的数学模型,非线性角度电位器可将转角量转化为电压或电阻信号,然后将非线性角度电位器用于仿真伺服控制系统的模拟位置闭环,仿真伺服控制系统整体结构采用四闭环控制.仿真实验表明,采用非线性角度电位器的仿真伺服系统具有较高的控制精度、功能完善、可维护性好、具有很强的鲁棒性.
段海滨 +3 more
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Changes in the transformative potential of action proposals in Finnish Red Lists from 1986 to 2019
Conservation Biology, Volume 40, Issue 4, August 2026.Abstract Red lists provide critical knowledge regarding biodiversity decline, especially in Finland, where broad assessments have been made regularly since the 1980s. They deliver information on the threat status of species and ecosystems, propose actions to guide conservation policy, and have the potential to spur transformative change.
Anni Arponen +4 more
wiley +1 more source
Guangtongxin yanjiu, 2008 文章介绍了高非线性光子晶体光纤的特点及产生高非线性特性的基本原理,分析了在高非线性光子晶体光纤中产生超连续光谱和慢光效应的机理和其应用,并给出了国内利用文章作者研制的高非线性光子晶体光纤进行超连续谱和慢光试验的结果。
李进延 +5 more
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Moving in Cycles: Explaining the Failure of Militarization to Address Illegal Mining in Ghana
Politics &Policy, Volume 54, Issue 4, August 2026.ABSTRACT Mining contributes to Ghana's economic growth but also imposes significant social costs—land dispossession and unemployment—which have fueled the rise of illegal mining (galamsey). Galamsey, which intensified during the commodity boom of the 2010s, provides livelihoods while simultaneously worsening environmental degradation and social ...
Sulemana Alhassan Saaka, Phil Faanu
wiley +1 more source
, 1979 星系密度波理论成功地解释了螺旋结构的缠卷困难。为了克服有限群速度引起的维持困难,人们研究了各种线性波的不稳定增长模式解。线性波的不稳定性分析只能适用于短的时间发展,所以应该进一步讨论非线性密度波的稳定性。徐遐生等用星系激波方程计算恒星的非线性密度波时发现,解极敏感地依赖于初值的选择,可能在物理上不稳定 ...
王联, 胡文瑞, 王慕秋, 秦元勋
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四川大学学报. 自然科学版, 1981 近年来由于非线性泛函分析理论的发展,应用这一理论的某些最新成果和方法于研究某些具体类型的非线性Volterra积分方程的工作也日渐增多.1975年Barbu[1]首先利用非线性单调算子理论,讨论过Hilbert空间中下面一类型非线性Volterra积分方程:
张石生
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