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Publications - 6374

Reassembling Naija Marxisms: Leftist thought and the socialist movement after 1989 in Nigeria

Adam Mayer

Publication Name: Canadian Journal of African Studies

Publication Date: 2021-01-01

Volume: 55

Issue: 2

Page Range: 331-349

Description:

Throughout the Cold War the USSR was the most important external source of funds, ideological transfers, and organizational help for Marxists in Nigeria. The events of 1989 and the USSR’s subsequent withdrawal from this role created a major hiatus for the Nigerian Left. In this article, I prove that Nigerian socialist movements and thinkers, after a short adjustment period, successfully recovered from the shock of 1989. I present a plethora of coping mechanisms that Leftist intellectuals employed as private survival strategies. I also show that the Nigerian Left as a movement retained their Marxist and radical inspirations, and it also grew and became suffused with a new spirit of human rights, gender sensitivity, and attention to ethnicity from the 1990s onward. The Nigerian Left turned the disappearance of its external backer from a calamity into an engine of growth and ethical conscientization after 1989.

Open Access: Yes

DOI: 10.1080/00083968.2020.1842218

Generative Hypergraph-based Kinematic Models for Virtual-Reality Applications

Adam Csapo Csaba Hajdu

Publication Name: 2022 1st IEEE International Conference on Cognitive Aspects of Virtual Reality Cvr 2022

Publication Date: 2022-01-01

Volume: Unknown

Issue: Unknown

Page Range: 11-16

Description:

Recently, virtual reality applications have become a prominent research area, along with related topics such as digital-twin applications and simulation of devices such as vehicles or cyber-physical systems. These topics are intimately linked with computer-based simulations and computer graphics. Consequently, accurately describing entities populating simulated worlds is a critical task. Relevant properties include but are not limited to an object's visual appearance and kinematic constraints. This paper proposes a hypergraph-based kinematic model aiming to describe virtual entities used in virtual reality applications and simulations. Compared to other popular schematics (e.g., URDF, SDF), a primary advantage of this approach is its reduced language element set, which is capable of minimally describing a conceptually very simple kind of hypergraph. This reduction, in turn, enables the description of simple graph triplets amenable to storage in graph databases or ontologies. The introduced format is aimed at enabling the flexible and efficient real-time exchange of visual and physical information on cognitive channels between entities. The possibility of transforming an instance of this model into other schematics (SDF, MaxWhere) is further demonstrated in the paper, which constructively proves the expressive capabilities of the model and helps support the claim that it is equivalent in expressive power to other widely used description models.

Open Access: Yes

DOI: 10.1109/CVR55417.2022.9967632

A maturity model to assess startups toward industry 4.0: Combined compromise solution approach

Mohsen Shafiei Nikabadi Dragan Pamucar Fatemeh Ghasemzadeh

Publication Name: Sustainable Futures

Publication Date: 2026-06-01

Volume: 11

Issue: Unknown

Page Range: Unknown

Description:

The fourth industrial revolution is the integration of new digital industrial technologies aimed at connecting and enabling interaction between humans, machines, and components, transforming production systems into fully automated and integrated equipment that communicate with each other. In this paper, we propose a new maturity model for Industry 4.0 (I4.0) startups using the combined compromise solution (CoCoSo) decision-making algorithm. This model assists companies seeking to transition their business towards I4.0 and can serve as a guiding procedure for systems on their path to full I4.0 implementation. First, we compile a list of key I4.0 dimensions from the literature and previous studies. Then, we gather opinions from industrial and academic experts to select the most relevant and important indicators for analyzing the maturity level of startups. We use the CoCoSo decision-making algorithm to prioritize the I4.0 dimensions and design the model elements. Three main sustainability dimensions are used as decision criteria with equal weight when prioritizing the I4.0 sub-dimensions. To evaluate the applicability of the model, we assess three Iranian startups operating at the Science and Technology Park using the proposed model and present the radar graph of their maturity level in each dimension. The proposed model can be readily used by startups to assess themselves, identify their strengths and weaknesses, better define improvement projects, and allocate their resources. To our knowledge, there is no similar assessment model in the literature that can be used by startups due to their innovative nature.

Open Access: Yes

DOI: 10.1016/j.sftr.2026.101728

Multigrid technique for biharmonic interpolation with application to dual and multiple reciprocity method

Csaba Gáspár

Publication Name: Numerical Algorithms

Publication Date: 1999-01-01

Volume: 21

Issue: 1-4

Page Range: 165-183

Description:

A biharmonic-type interpolation method is presented to solve 2D and 3D scattered data interpolation problems. Unlike the methods based on radial basis functions, which produce a large linear system of equations with fully populated and often non-selfadjoint and ill-conditioned matrix, the presented method converts the interpolation problem to the solution of the biharmonic equation supplied with some non-usual boundary conditions at the interpolation points. To solve the biharmonic equation, fast multigrid techniques can be applied which are based on a non-uniform, non-equidistant but Cartesian grid generated by the quadtree/octtree algorithm. The biharmonic interpolation technique is applied to the multiple and dual reciprocity method of the BEM to convert domain integrals to the boundary. This makes it possible to significantly reduce the computational cost of the evaluation of the appearing domain integrals as well as the memory requirement of the procedure. The resulting method can be considered as a special grid-free technique, since it requires no domain discretisation.

Open Access: Yes

DOI: 10.1023/a:1019173816678

On the Schur component preconditioners

Béla Kiss A. Krebsz

Publication Name: Computers and Structures

Publication Date: 1999-01-01

Volume: 73

Issue: 1-5

Page Range: 537-544

Description:

Some representations of the H 1/2 norm are used as Schur complement preconditioners in PCG-based domain decomposition algorithms for elliptic problems. These norm representations are efficient preconditioners. Here we give a new matrix representation of the Ha (0 < a < 1) norms by a special sparse Toeplitz matrix. It contains O(log(N)) non-zero entries at each row, where N is the number of rows. The special properties of this matrix ensure that it can be used as preconditioner. This is proved by estimating spectral equivalence constants and this fact has also been verified by numerical tests.

Open Access: Yes

DOI: 10.1016/S0045-7949(98)00258-2

The Dissonance Within: Identity Regulation and Its Impact on Social Media Discontinuance Intentions

Irum Shahzadi Ankit Mehrotra Nourah O. Alshaghdali Dhruv Galgotia Sushant Kumar Vishnoi Irum Shahzadi

Publication Name: Journal of Global Information Management

Publication Date: 2025-01-01

Volume: 33

Issue: 1

Page Range: Unknown

Description:

This study employs Identity Regulation Theory (IRT) to investigate how identity-related psychological tensions, such as identity incongruence and dissonance, influence the discontinuation intentions of social media users. Using a cross-sectional survey of 294 active users via Prolific Academic, structural equation modeling (PLS-SEM) was employed to analyze the relationships among these tensions, platform fatigue, and discontinuation. Results show neither tension directly affects discontinuation, but both influence it through platform fatigue. This offers a new perspective on the psychological costs of social media, with fatigue serving as a key mediator in transforming identity tension into discontinuation intent. The paper adds to IRT research and helps firms understand why users leave social media.

Open Access: Yes

DOI: 10.4018/JGIM.392502

Approximation of a modified traveling salesman problem using bacterial memetic algorithms

János Botzheim Peter Foldesi Márk Farkas Ĺaszĺo T. Ḱoczy

Publication Name: Studies in Computational Intelligence

Publication Date: 2009-12-01

Volume: 243

Issue: Unknown

Page Range: 607-625

Description:

The goal of this paper is to develop an algorithm that is capable to handle a slightly modified version of the minimal Traveling Salesman Problem in an efficient and robust way and produces high-quality solutions within a reasonable amount of time. The requirements of practical logistical applications, such as road transportation and supply chains, are also taken into consideration in this novel approach of the TSP. This well-known combinatorial optimization task is solved by a bacterial memetic algorithm, which is an evolutionary algorithm inspired by bacterial transduction. A new method is also proposed to deal with the time dependency in the cost matrix. The efficiency of the implementation, including time and space constraints, is investigated on a real life problem. © 2009 Springer-Verlag Berlin Heidelberg.

Open Access: Yes

DOI: 10.1007/978-3-642-03737-5_44

Invariance conditions for nonlinear dynamical systems

Yunfei Song Tamás Terlaky Zoltán Horváth

Publication Name: Springer Optimization and Its Applications

Publication Date: 2016-01-01

Volume: 115

Issue: Unknown

Page Range: 265-280

Description:

Recently,Horváth et al. (Appl Math Comput,submitted) proposed a novel unified approach to study,i.e.,invariance conditions,sufficient and necessary conditions,under which some convex sets are invariant sets for linear dynamical systems. In this paper,by utilizing analogous methodology,we generalize the results for nonlinear dynamical systems. First,the Theorems of Alternatives,i.e.,the nonlinear Farkas lemma and the S-lemma,together with Nagumo’s Theorem are utilized to derive invariance conditions for discrete and continuous systems. Only standard assumptions are needed to establish invariance of broadly used convex sets,including polyhedral and ellipsoidal sets. Second,we establish an optimization framework to computationally verify the derived invariance conditions. Finally,we derive analogous invariance conditions without any conditions.

Open Access: Yes

DOI: 10.1007/978-3-319-42056-1_8

The use and abuse of legal history. On the nature of the censorial regimen morum

Gergely Deli

Publication Name: Journal on European History of Law

Publication Date: 2021-01-01

Volume: 12

Issue: 1

Page Range: 138-144

Description:

The paper analyses the nature of enforcement within the censorial regimen morum (CRM) in Ancient Rome by taking into consideration various Latin legal and literary sources. It comes to the conclusion that CRM could be seen as a transitional institution in a system which evolved from a formerly domaninant collective or decentralized to a more centralized enforcement. It also enriches the debate on the concept of law through historical insights by claiming that a social order can meaningfully called a legal order only if centralized production and enforcement of norms had been already added to the consensus of some commonly shared values.

Open Access: Yes

DOI: DOI not available