Results 51 to 60 of about 18,331 (226)

Pseudo-loadflow formulation as a starting process for the Newton Raphson

, 2010
This paper introduces new models which approximate the AC loadflow problem, but are able to converge (using the Newton Raphson algorithm) from a wider range of starting points.
Irving, MR
core   +1 more source

Review and prospects of shear test of bolted rock joints

Deep Underground Science and Engineering, EarlyView.
The laboratory shear test equipment, test method, and numerical simulation of bolted rock joints were summarized. The shortcomings and limitations of the current research were analyzed, and the research prospects were proposed. Abstract Rock bolting is a critical approach in geotechnical engineering for supporting weak rocks.
Shulin Ren, Fan Yang, Manchao He, Yong Yuan, Zhigang Tao   +4 more
wiley   +1 more source

Improved New Two-Spectral Conjugate Gradient Iterative Technique for Large Scale Optimization

Mağallaẗ Al-kūfaẗ Al-handasiyyaẗ
Numerous strategies have been proposed in the field of unconstrained optimization to address various optimization challenges, particularly those associated with large-scale systems. Among the classical methods, Newton and Quasi-Newton approaches are well-
Radhwan Basem Thanoon, Ghada Moayid Al-Naemi   +1 more
doaj   +1 more source

Memoryless quasi-Newton-type methods via some weak secant relations for large-scale unconstrained optimization

Journal of Inequalities and Applications
Abstract This article presents two variants of memoryless quasi-Newton methods with backtracking line search for large-scale unconstrained minimization. These updating methods are derived by means of a least-change updating strategy subjected to some weaker form of secant relation obtained by projecting the secant equation onto the search direction. In
Lim, Keat Hee, Leong, Wah June
openaire   +2 more sources

Weak‐Story Mitigation and Drift Redistribution in Moment‐Resisting Frames Using Stepping Rocking Walls

Earthquake Engineering &Structural Dynamics, EarlyView.
ABSTRACT This study investigates the seismic response of moment‐resisting frames retrofitted with a stepping rocking wall, with emphasis on weak‐story mitigation and residual drift reduction under both ordinary and pulse‐like ground motions. Nonlinear response‐history analyses are conducted on 9‐story and 20‐story SAC Los Angeles frames.
Mehrdad Aghagholizadeh
wiley   +1 more source

Applied Element Modelling of Out‐Of‐Plane Instability in Boundary Elements of Thin RC Walls

Earthquake Engineering &Structural Dynamics, EarlyView.
ABSTRACT Recent earthquakes in Chile (2010) and New Zealand (2011) caused extensive damage to buildings featuring reinforced concrete (RC) structural walls, with observed failure modes including out‐of‐plane instability of slender walls. This buckling‐type response under combined in‐plane and out‐of‐plane loading has also been documented in ...
Andrea Orgnoni, Rui Pinho, João Pacheco de Almeida   +2 more
wiley   +1 more source

Acceleration of the EM algorithm by using quasi-Newton methods

, 1997
The EM algorithm is a popular method for maximum likelihood estimation. Its simplicity in many applications and desirable convergence properties make it very attractive.
Jennrich, Robert I., Jamshidian, Mortaza
core   +2 more sources

Variance-Guided Regression for Heteroscedastic Data With a Grouping-Based Extension for Nonlinear Prediction. [PDF]

Stat Med
ABSTRACT Although homoscedasticity is often assumed in linear regression, real data may show variance patterns or residual structures that violate this assumption. We propose VarGuid, a variance‐guided framework for two related settings: Covariate‐dependent conditional variance under a global linear mean model, and residual nonlinear mean structure ...
Liu S, Lu M.
europepmc   +2 more sources

Identifying the age cohort responsible for transmission in a natural outbreak of Bordetella bronchiseptica. [PDF]

, 2010
Identifying the major routes of disease transmission and reservoirs of infection are needed to increase our understanding of disease dynamics and improve disease control. Despite this, transmission events are rarely observed directly.
Pritt, Stacy, Gráinne H Long, Eric T. Harvill, Sinha, Divya, Stacy Pritt, Ottar N Bjørnstad, Kline, Barry, Bjørnstad, Ottar N, Harvill, Eric T, Hudson, Peter J, Gráinne H. Long, Ottar N. Bjørnstad, Peter J. Hudson, Long, Gráinne H, Andrew F Read, Peter J Hudson, Barry Kline, Divya Sinha, Eric T Harvill, Read, Andrew F, Andrew F. Read   +20 more
core   +1 more source

Stability Evaluation and Parametric Optimization of Coal‐Concrete Composite Bearing Systems Under Mine‐Water‐Induced Deterioration: Experiments and FEINN Analysis

Energy Science &Engineering, EarlyView.
Mine‐water immersion tests reveal pronounced coal weakening (vs. minor concrete degradation), identifying coal pillars as the stability‐limiting component in composite dams. A coupled FEINN framework quantifies extreme‐pressure stability and ranks multi‐parameter designs via a normalized multi‐indicator scheme, enabling optimized dam configuration for ...
He Wen, Hongchuan Dai, Guixin Zhang, Pengzhe Li, Tong Yang, Cang Gong, Renbo Gao   +6 more
wiley   +1 more source