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Model order reduction for large-scale structures with local nonlinearities

In solid mechanics, linear structures often exhibit (local) nonlinear behavior when close to failure. For instance, the elastic deformation of a structure becomes plastic after being deformed beyond recovery. To properly assess such problems in a real-life application, we need fast and multi-query evaluations of coupled linear and nonlinear structural systems, whose approximations are not straight

Goal-oriented error estimation for beams on elastic foundation with double shear effect

In this paper, goal-oriented error estimation for Timoshenko beams on Pasternak foundation, which involves double shear effect, is performed. The constitutive relation error (CRE) estimation is used in finite element analysis (FEA) to acquire strict bounds on quantities of interest. Due to the coupling of the displacement field and the internal force field in the equilibrium equations of the beam,

Strict upper and lower bounds of quantities for beams on elastic foundation by dual analysis

Purpose - The purpose of this paper is to acquire strict upper and lower bounds on quantities of slender beams on Winkler foundation in finite element analysis. Design/methodology/approach - It leans on the dual analysis wherein the constitutive relation error (CRE) is used to perform goal-oriented error estimation. Due to the coupling of the displacement field and the stress field in the equilibr

Constitutive-relation-error-based a posteriori error bounds for a class of elliptic variational inequalities

On the basis of the dual variational formulation of a class of elliptic variational inequalities, a constitutive relation error is defined for the variational inequalities as an a posteriori error estimator, which is shown to guarantee strict upper bounds of the global energy-norm errors of kinematically admissible solutions. A numerical example is presented to validate the strictly bounding prope

Weak form quadrature solution of 2mth-order Fredholm integro-differential equations

A method is proposed for the solution of boundary-value problems of linear and non-linear 2mth-order Fredholm integro-differential equations. A set of algebraic equations are obtained after introduction of Gauss–Lobatto quadrature and the generalized differential quadrature analog into the weak form description of a Fredholm integro-differential equation. Numerical examples are presented to demons

Strict upper and lower bounds for quantities of interest in static response sensitivity analysis

In this paper, a goal-oriented error estimation technique for static response sensitivity analysis is proposed based on the constitutive relation error (CRE) estimation for finite element analysis (FEA). Strict upper and lower bounds of various quantities of interest (QoI) that are associated with the response sensitivity derivative fields are acquired. Numerical results are presented to assess th

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For model verification which is mainly focused on the control of discretization errors of numerical results, a posteriori error estimation plays an important role in various numerical tools such as the finite element method. The outputs of interest are usually converted into integral functionals over the problem domain for a posteriori error analysis. Among the available techniques for goal-orient

Lossa bromsen på det etniska företagandet

De samhälleliga och mänskliga kostnaderna för långvarigt utanförskap är förödande.Exemplet med den somaliska integrationen i Minnesota i USA visar att det skulle kunna vara annorlunda – men det kräver att vi gör upp med vår misstänksamhet mot etniskt företagande, skriver Benny Carlsson och Andreas Johansson Heinö.

How Rigidity and Conjugation of Bidentate Ligands Affect the Geometry and Photophysics of Iron N-Heterocyclic Complexes : A Comparative Study

Two iron complexes featuring the bidentate, nonconjugated N-heterocyclic carbene (NHC) 1,1′-methylenebis(3-methylimidazol-2-ylidene) (mbmi) ligand, where the two NHC moieties are separated by a methylene bridge, have been synthesized to exploit the combined influence of geometric and electronic effects on the ground- and excited-state properties of homoleptic FeIII-hexa-NHC [Fe(mbmi)3](PF6)3 and h

The Space-Charge Problem in Ultrafast Diagnostics : An All-Optical Solution for Streak Cameras

The field of ultrafast science is dependent on either ultrashort laser pulse technology or ultrafast passive detection. While there exists a plethora of sub-picosecond laser pulse solutions, streak cameras are singular in providing sub-picosecond passive imaging capabilities. Therefore, their use in fields ranging from medicine to physics is prevalent. Streak cameras attain such temporal resolutio

The Core Elements of Psychiatric and Mental Health Nursing : Time, Honest Engagement, Therapeutic Relations, Professional Nursing and Lifetime-Perspective

Defining psychiatric and mental health nursing has been a challenge for decades, and it is still difficult to find a comprehensive definition. We have identified a possibility to clarify psychiatric and mental health nursing based on humanistic philosophy in a general psychiatric care context. The aim was therefore to identify and synthesize the theoretical frameworks from which psychiatric and me

Domaren som tjänsteman - domares uppdrag i förvaltningsmyndigheter

Det finns ett ganska stort antal bestämmelser om att förvaltningsmyndigheter – ofta organiserade som domstolsliknande nämnder – ska ha medverkan av ordinarie domare. I detta bidrag ges en översikt över när lagstiftningen kräver sådandomarmedverkan. Dessutom diskuteras vad ordinarie domares uppdrag i sådana organ innebär praktiskt och principiellt, främst i statsrättsligt och förvaltningsrättsligt

Evaluation Practices of Doctoral Examination Committees : Boundary-Work Under Pressure

The doctorate forms the basis for academic careers and the regeneration of academia, and has increasingly become important for other sectors of society. The latter is reflected in efforts on institutional, national as well as supranational levels to change and adapt the doctoral degree to new expectations. As doctoral education is embedded in research, changes in governance and funding of research

Pre-fusion motion state determines the heterogeneity of membrane fusion dynamics for large dense-core vesicles

Aim: In neuroendocrine cells, large dense-core vesicles (LDCVs) undergo highly regulated pre-fusion processes before releasing hormones via membrane fusion. Significant heterogeneity has been found for LDCV population based on the dynamics of membrane fusion. However, how the pre-fusion status impacts the heterogeneity of LDCVs still remains unclear. Hence, we explored pre-fusion determinants of h

Reversible Hydration Enabling High-Rate Aqueous Li-Ion Batteries

Layered TiS2 has been proposed as a versatile host material for various battery chemistries. Nevertheless, its compatibility with aqueous electrolytes has not been thoroughly understood. Herein, we report on a reversible hydration process to account for the electrochemical activity and structural evolution of TiS2 in a relatively dilute electrolyte for sustainable aqueous Li-ion batteries. Solvate

Robustness and dosimetric verification of hippocampal-sparing craniospinal pencil beam scanning proton plans for pediatric medulloblastoma

Background and Purpose: Hippocampal-sparing (HS) is a method that can potentially reduce late cognitive complications for pediatric medulloblastoma (MB) patients treated with craniospinal proton therapy (PT). The aim of this study was to investigate robustness and dosimetric plan verification of pencil beam scanning HS PT. Materials and Methods: HS and non-HS PT plans for the whole brain part of c

Tau accumulation and its spatial progression across the Alzheimer’s disease spectrum

The accumulation of tau abnormality in sporadic Alzheimer’s disease is believed typically to follow neuropathologically defined Braak staging. Recent in-vivo PET evidence challenges this belief, however, as accumulation patterns for tau appear heterogeneous among individuals with varying clinical expressions of Alzheimer’s disease. We, therefore, sought a better understanding of the spatial distri

Diffusion weighted magnetic resonance spectroscopy revealed neuronal specific microstructural alterations in Alzheimer’s disease

In Alzheimer’s disease, reconfiguration and deterioration of tissue microstructure occur before substantial degeneration become evident. We explored the diffusion properties of both water, a ubiquitous marker measured by diffusion MRI, and N-acetyl-aspartate, a neuronal metabolite probed by diffusion-weighted magnetic resonance spectroscopy, for investigating cortical microstructural changes downs