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Found 6383 publications

Euro area economic growth between 2010 and 2019 in the light of secular stagnation theory

Eszter Kazinczy Tatay Tibor

Publication Name: Public Finance Quarterly

Publication Date: 2023-09-29

Volume: 69

Issue: 3

Page Range: 72-88

Description:

Achieving economic growth remains an important issue for economic policy today. Growth in developed economies has slowed considerably in recent decades. In our study, we examine economic growth in the euro area between 2010 and 2019 in the light of secular stagnation theory. The concept of secular stagnation was developed by Hansen after the Great Depression of 1929-33. According to this theory, the causes of secular stagnation are low population growth and weak technological development. The concept was brought back into the economic discourse after 2010 by Summers. Following the 2008 crisis, euro area economies should have adjusted to a higher growth rate. Instead, growth remained below 2% for all but one year, below potential output for most of the decade. Investment rates have barely risen despite euro interest rates falling to near zero. The euro areas population barely grew despite a net migration surplus, putting a brake on employment growth. The available data suggest that neither employment growth nor productivity growth have boosted economic growth. The low level of economic growth and the evolution of the underlying factors are consistent with the theoretical assumptions described by Hansen and his followers.

Open Access: Yes

DOI: 10.35551/PFQ_2023_3_4

Exchange interaction between two quantum dots coupled through a superconducting island

Rok Žitko Ádám Bácsi Luka Pavešić

Publication Name: Physical Review B

Publication Date: 2023-09-15

Volume: 108

Issue: 11

Page Range: Unknown

Description:

We present a theoretical study of a system consisting of a superconducting island and two quantum dots, a possible platform for building qubits and Cooper pair splitters, in the regime where each dot hosts a single electron and, hence, carries a magnetic moment. We focus on the case where the dots are coupled to overlapping superconductor states and we study whether the spins are ferromagnetically or antiferromagnetically aligned. We show that if the total number of particles is even the spins align antiferromagnetically in the flatband limit, i.e., when the bandwidth of the superconductor is negligibly small, but they align ferromagnetically if the bandwidth is finite and above some value. If the total number of particles is odd, the alignment is ferromagnetic independently from the bandwidth. This implies that the results of the flatband limit are applicable only within a restricted parameter regime for realistic superconducting qubit systems and that some care is required in applying simplified models to devices such as Cooper pair splitters.

Open Access: Yes

DOI: 10.1103/PhysRevB.108.115160

Hierarchical fuzzy system modeling by genetic and bacterial programming approaches

János Botzheim Krisztián Balázs László T. Kóczy

Publication Name: 2010 IEEE World Congress on Computational Intelligence Wcci 2010

Publication Date: 2010-11-25

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

In this paper a method is proposed for constructing hierarchical fuzzy rule bases in order to model black box systems defined by input-output pairs, i.e. to solve supervised machine learning problems. The resultant hierarchical rule base is the knowledge base, which is constructed by using structure constructing evolutionary techniques, namely, Genetic and Bacterial Programming Algorithms. Applying hierarchical fuzzy rule bases is a way of reducing the complexity of the knowledge base, whereas evolutionary methods ensure a relatively efficient learning process. This is the reason of the investigation of this combination. © 2010 IEEE.

Open Access: Yes

DOI: 10.1109/FUZZY.2010.5584220

Experimental and numerical investigation of internally reinforced damaged pipelines

Balázs Pere J. Lukács Gy Nagy János Égert I. Török

Publication Name: 18th European Conference on Fracture Fracture of Materials and Structures from Micro to Macro Scale

Publication Date: 2010-12-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

The purpose of the paper is to present the role of the internal reinforcing on the structural integrity of steel pipes, based on numerical and experimental investigations. For FE analysis of unreinforced case three mechanical models were applied: multilayered elastic shell, 3D elastic solid and 3D elastic-plastic solid FE models. The aim of the numerical analysis was to clarify deformations, stresses and strains in the surrounding area of defects both in the steel pipe and on the composite reinforcement. A further task is to determine numerically the width of reinforcement and the number of layers needed for the repair. For experimental investiga-Tions internal reinforcement was developed using glass fibre polymer matrix composite. Fa-Tigue and burst tests were performed on pipe sections containing artificial metal loss defects. Both unreinforced and reinforced pipeline sections were examined. The applicability of the hybrid structure was demonstrated by means of the numerical and the experimental results.

Open Access: Yes

DOI: DOI not available

Some examples of computing the possibilistic correlation coefficient from joint possibility distributions

József Mezei Peter Varlaki Robert Fuller

Publication Name: Studies in Computational Intelligence

Publication Date: 2010-11-03

Volume: 313

Issue: Unknown

Page Range: 153-170

Description:

In this paper we will show some examples for computing the possibilistic correlation coefficient between marginal distributions of a joint possibility distribution. First we consider joint possibility distributions, (1-x-y), (1-x 2-y 2), and (1-x 2-y) on the set {(x,y)≡R2| x≥0,y≥0,x+y≤1}, then we will show (i) how the possibilistic correlation coefficient of two linear marginal possibility distributions changes from zero to -1/2, and from -1/2 to -3/5 by taking out bigger and bigger parts from the level sets of a their joint possibility distribution; (ii) how to compute the autocorrelation coefficient of fuzzy time series with linear fuzzy data. © 2010 Springer-Verlag Berlin Heidelberg.

Open Access: Yes

DOI: 10.1007/978-3-642-15220-7_13

Computational thinking and self-leadership as predictor of innovative work behavior among employees in green product firms : An explanatory sequential mixed method

Hamid Waqas Md Billal Hossain Saad Saif Bin Li

Publication Name: Acta Psychologica

Publication Date: 2026-07-01

Volume: 267

Issue: Unknown

Page Range: Unknown

Description:

This study employed an explanatory sequential mixed-method design to investigate the factors influencing innovative work behavior in green product firms in Pakistan. Guided by social cognitive theory, data from 278 employees were analyzed using structural equation modeling in AMOS, followed by qualitative interviews to further explain and contextualize the quantitative findings. The findings showed that computational thinking (β = 0.62, p < 0.001) and self‑leadership (β = 0.56, p < 0.001) have a significant positive association with creative self-efficacy. Additionally, creative self-efficacy has a significant direct positive influence on innovative work behavior (β = 0.76, p < 0.001). The mediation analysis confirmed that creative self-efficacy significantly mediated the relationship between computational thinking and innovative work behavior (indirect β = 0.29) and between self‑leadership and innovative work behavior (indirect β = 0.26). Notably, knowledge sharing significantly moderated the relationship between creative self-efficacy and innovative work behavior (β = 0.32, p < 0.001) strengthening the effect of creative self-belief on innovative. Eighteen (n = 18) interviews were conducted to gain insight into how these mechanisms worked. During the thematic analysis, results revealed that knowledge sharing weakens negative effect of hierarchical constraints, enabling employees to act on their creative self-efficacy. Computational thinking is associated with a language of credibility for innovative ideas, while self‑leadership is associated with a necessary internal motivation against bureaucratic fatigue. These findings are relevant for green product firms operating in high power distance, resource-constrained contexts such as Pakistan.

Open Access: Yes

DOI: 10.1016/j.actpsy.2026.107030

Fuzzy signature based fuzzy communication of mobile robots

Claudiu Radu Pozna Áron Ballagi László T. Kóczy

Publication Name: 2010 IEEE Rivf International Conference on Computing and Communication Technologies Research Innovation and Vision for the Future Rivf 2010

Publication Date: 2010-12-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

This paper presents a novel method for control cooperating robots where the explicit communication line is substituted with fuzzy communication algorithms. Fuzzy signatures are used in a context dependent codebook, as complex state description method for intention guessing and action selection. Finally a possible cooperative robot application on a realistic example with missing data components will be shown. ©2010 IEEE.

Open Access: Yes

DOI: 10.1109/RIVF.2010.5633066

Material Models to Study the Effect of Fines in Sandy Soils Based on Experimental and Numerical Results

Ammar N. Alnmr

Publication Name: Acta Technica Jaurinensis

Publication Date: 2021-11-24

Volume: 14

Issue: 4

Page Range: 651-680

Description:

Choosing and calibrating a robust and accurate soil material model (constitutive model) is the first important step in geotechnical numerical modelling. A less accurate model leads to poor results and more difficulty estimating true behaviour in the field. Subsequent design work is compromised and may lead to dangerous and costly mistakes. In this research, laboratory experimental results were used as a basis to evaluate several soil material models offered in Plaxis2D software. The deciding feature of the soil model was how well it could represent effects of percentage of fine material within sandy soils to simulate its behaviour. Results indicate that the Hardening Soil (HS) model works well when the percentage of fine (soft) materials is less than 10%. Above that level, the Soft Soil model (SS) becomes the most suitable. Finally, some important conclusions about this research and recommendations for future research are highlighted.

Open Access: Yes

DOI: 10.14513/actatechjaur.00625

Artificial neural network analysis of chemical reaction and radiation effects on MHD ternary nanofluid flow over an exponentially accelerated inclined plate

S. V.K. Varma B. T. Raju Hijaz Ahmad Waleed Mohammed Abdelfattah Charankumar Ganteda Hameed Miya

Publication Name: South African Journal of Chemical Engineering

Publication Date: 2026-07-01

Volume: 57

Issue: Unknown

Page Range: Unknown

Description:

This investigation explores the magnetohydrodynamic (MHD) free convective heat and mass transfer characteristics of a ternary nanofluid traversing an exponentially accelerated inclined plate within a porous medium. The theoretical framework integrates the complexities of internal heat generation/absorption and fluctuating wall temperatures. Analytical solutions were rigorously derived utilizing the Laplace transform technique, while a sophisticated Artificial Neural Network (ANN) was implemented to forecast and corroborate these mathematical outcomes. Heat Transfer (Nusselt Number) evaluated against the interplay of the Prandtl number, thermal radiation parameters, and temporal progression. Mass Transfer (Sherwood Number) analyzed as a function of magnetic permeability, the Schmidt number, and time. Thermal Enhancement findings indicate that an augmentation in the nanofluid volume fraction significantly bolsters thermal conductivity, thereby elevating the temperature profile. The proposed Levenberg-Marquardt Algorithm-based Backpropagation Artificial Neural Network (LMA BANN) demonstrated exceptional predictive fidelity. The model achieved a precision threshold exceeding 99.9% for the Nusselt number and near-perfect accuracy for the Sherwood number. These results are substantiated by negligible Mean Squared Error (MSE), Root Mean Squared Error (RMSE), and Mean Absolute Error (MAE) values, coupled with correlation coefficients (R) nearing unity, signifying a robust alignment between the analytical and predicted datasets.

Open Access: Yes

DOI: 10.1016/j.sajce.2026.100912