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Open Access
Article
Publication date: 20 December 2022

Quivine Ndomo, Ilona Bontenbal and Nathan A. Lillie

The purpose of this paper is to characterise the position of highly educated African migrants in the Finnish labour market and to examine the impact of the COVID-19 pandemic on…

Abstract

Purpose

The purpose of this paper is to characterise the position of highly educated African migrants in the Finnish labour market and to examine the impact of the COVID-19 pandemic on that position.

Design/methodology/approach

The paper is based on the biographical work stories of 17 highly educated African migrant workers in four occupation areas in Finland: healthcare, cleaning, restaurant and transport. The sample was partly purposively and partly theoretically determined. The authors used content driven thematic analysis technique, combined with by the biographical narrative concept of turning points.

Findings

Using the case of highly educated African migrants in the Finnish labour market, the authors show how student migration policies reinforce a pattern of division of labour and occupations that allocate migrant workers to typical low skilled low status occupations in the secondary sector regardless of level of education, qualification and work experience. They also show how the unique labour and skill demands of the COVID-19 pandemic incidentally made these typical migrant occupations essential, resulting in increased employment and work security for this group of migrant workers.

Research limitations/implications

This research and the authors’ findings are limited in scope owing to sample size and methodology. To improve applicability of findings, future studies could expand the scope of enquiry using e.g. quantitative surveys and include other stakeholders in the study group.

Originality/value

The paper adds to the knowledge on how migration policies contribute to labour market dualisation and occupational segmentation in Finland, illustrated by the case of highly educated African migrant workers.

Details

International Journal of Sociology and Social Policy, vol. 43 no. 3/4
Type: Research Article
ISSN: 0144-333X

Keywords

Open Access
Article
Publication date: 28 February 2024

Luke Mizzi, Arrigo Simonetti and Andrea Spaggiari

The “chiralisation” of Euclidean polygonal tessellations is a novel, recent method which has been used to design new auxetic metamaterials with complex topologies and improved…

Abstract

Purpose

The “chiralisation” of Euclidean polygonal tessellations is a novel, recent method which has been used to design new auxetic metamaterials with complex topologies and improved geometric versatility over traditional chiral honeycombs. This paper aims to design and manufacture chiral honeycombs representative of four distinct classes of 2D Euclidean tessellations with hexagonal rotational symmetry using fused-deposition additive manufacturing and experimentally analysed the mechanical properties and failure modes of these metamaterials.

Design/methodology/approach

Finite Element simulations were also used to study the high-strain compressive performance of these systems under both periodic boundary conditions and realistic, finite conditions. Experimental uniaxial compressive loading tests were applied to additively manufactured prototypes and digital image correlation was used to measure the Poisson’s ratio and analyse the deformation behaviour of these systems.

Findings

The results obtained demonstrate that these systems have the ability to exhibit a wide range of Poisson’s ratios (positive, quasi-zero and negative values) and stiffnesses as well as unusual failure modes characterised by a sequential layer-by-layer collapse of specific, non-adjacent ligaments. These findings provide useful insights on the mechanical properties and deformation behaviours of this new class of metamaterials and indicate that these chiral honeycombs could potentially possess anomalous characteristics which are not commonly found in traditional chiral metamaterials based on regular monohedral tilings.

Originality/value

To the best of the authors’ knowledge, the authors have analysed for the first time the high strain behaviour and failure modes of chiral metamaterials based on Euclidean multi-polygonal tessellations.

Details

Rapid Prototyping Journal, vol. 30 no. 11
Type: Research Article
ISSN: 1355-2546

Keywords

Open Access
Article
Publication date: 18 January 2021

Hongxing Wang, LianZheng Ge, Ruifeng Li, Yunfeng Gao and Chuqing Cao

An optimal solution method based on 2-norm is proposed in this study to solve the inverse kinematics multiple-solution problem caused by a high redundancy. The current research…

1020

Abstract

Purpose

An optimal solution method based on 2-norm is proposed in this study to solve the inverse kinematics multiple-solution problem caused by a high redundancy. The current research also presents a motion optimization based on the 2-Norm of high-redundant mobile humanoid robots, in which a kinematic model is designed through the entire modeling.

Design/methodology/approach

The current study designs a highly redundant humanoid mobile robot with a differential mobile platform. The high-redundancy mobile humanoid robot consists of three modular parts (differential driving platform with two degrees of freedom (DOF), namely, left and right arms with seven DOF, respectively) and has total of 14 DOFs. Given the high redundancy of humanoid mobile robot, a kinematic model is designed through the entire modeling and an optimal solution extraction method based on 2-norm is proposed to solve the inverse kinematics multiple solutions problem. That is, the 2-norm of the angle difference before and after rotation is used as the shortest stroke index to select the optimal solution. The optimal solution of the inverse kinematics equation in the step is obtained by solving the minimum value of the objective function of a step. Through the step-by-step cycle in the entire tracking process, the kinematic optimization of the highly redundant humanoid robot in the entire tracking process is realized.

Findings

Compared with the before and after motion optimizations based on the 2-norm algorithm of the robot, its motion after optimization shows minimal fluctuation, improved smoothness, limited energy consumption and short path during the entire mobile tracking and operating process.

Research limitations/implications

In this paper, the whole kinematics model of the highly redundant humanoid mobile robot is established and its motion is optimized based on 2-norm, which provides a theoretical basis for the follow-up research of the service robot.

Practical implications

In this paper, the whole kinematics model of the highly redundant humanoid mobile robot is established and its motion is optimized based on 2-norm, which provides a theoretical basis for the follow-up research of the service robot.

Social implications

In this paper, the whole kinematics model of the highly redundant humanoid mobile robot is established and its motion is optimized based on 2-norm, which provides a theoretical basis for the follow-up research of the service robot.

Originality/value

Motion optimization based on the 2-norm of a highly redundant humanoid mobile robot with the entire modeling is performed on the basis of the entire modeling. This motion optimization can make the highly redundant humanoid mobile robot’s motion path considerably short, minimize energy loss and shorten time. These researches provide a theoretical basis for the follow-up research of the service robot, including tracking and operating target, etc. Finally, the motion optimization algorithm is verified by the tracking and operating behaviors of the robot and an example.

Details

Assembly Automation, vol. 41 no. 2
Type: Research Article
ISSN: 0144-5154

Keywords

Open Access
Article
Publication date: 3 November 2020

Dalia Abdelwahab, Nadia Jiménez, Sonia San-Martín and Jana Prodanova

This research aims to address ethnocentric consumers’ willingness to boycott dual origin brands, in the particular case of national brands linked to a very specific regional…

3504

Abstract

Purpose

This research aims to address ethnocentric consumers’ willingness to boycott dual origin brands, in the particular case of national brands linked to a very specific regional origin, through analysing the paradox of (unfavourable) regional ethnocentrism versus (favourable) consumer–brand relationship (i.e. brand identification, trust and love) on consumers’ decision to buy or boycott those brands in that circumstances. Building on social identity and cognitive dissonance theories, this study aims to examine the Spanish consumer relationship with national brands originated in Catalonia considering the current conflicting circumstances in the region.

Design/methodology/approach

The authors collected data by means of personal questionnaires, distributed among 277 Spanish consumers of Catalan brands of Cava. The data is analysed by using structural equation modelling and linear structural relations.

Findings

After controlling for brand familiarity, the results of this study reveal that ethnocentrism negatively distorts consumers’ confidence in dual origin brands and highlight the role of identification and trust as brand love antecedents. It also reveals that ethnocentrism has a more profound impact on boycotting decision than brand love.

Originality/value

This study is one of the few to capture the puzzlement created by the paradoxical nature of the brand’s duality of origin. Furthermore, it contributes to the marketing literature by examining the impact of ethnocentrism on two relationship variables (i.e. identification and trust) and exploring their joint impact on consumers’ decision to buy or boycott. The findings of this study can be helpful for companies facing boycotting behaviour triggered by ethnocentric consumer reaction towards dual origin brands.

Propósito

Esta investigación tiene como objetivo abordar la disponibilidad de los consumidores etnocéntricos para boicotear las marcas de origen dual -en el caso particular de marcas nacionales vinculadas a un origen regional muy específico-, mediante el análisis de la paradoja del (desfavorable) etnocentrismo regional versus la relación (favorable) entre el consumidor y la marca (es decir, la identificación, la confianza y el amor a la marca) en la decisión de los consumidores de comprar o boicotear dichas marcas en esas circunstancias. Partiendo de las teorías de la identidad social y la disonancia cognitiva, este estudio examina la relación del consumidor español con las marcas nacionales originales de Cataluña, considerando las circunstancias conflictivas actuales en la región.

Diseño/método

Los datos se recogieron mediante cuestionarios personales, distribuidos entre 277 consumidores españoles de marcas catalanas de Cava. Los datos se analizaron utilizando modelación de ecuaciones estructurales y relaciones estructurales lineales.

Hallazgos

Después de controlar la familiaridad con la marca, nuestros resultados revelan que el etnocentrismo distorsiona negativamente la confianza de los consumidores en las marcas de origen dual y destaca el papel de la identificación y la confianza como antecedentes del amor por la marca. También revela que el etnocentrismo tiene un impacto más profundo en la decisión de boicotear que el amor por la marca.

Originalidad/valor

Este estudio es uno de los pocos que captura la confusión creada por la naturaleza paradójica de la dualidad del origen de la marca. Además, contribuye a la literatura de marketing al examinar el impacto del etnocentrismo en dos variables relacionales (la identificación y la confianza) y explorar su impacto conjunto en la decisión de los consumidores de comprar o boicotear. Nuestros hallazgos pueden ser útiles para las empresas que se enfrentan al comportamiento de boicot provocado por la reacción etnocéntrica de los consumidores hacia las marcas de origen dual.

Open Access
Article
Publication date: 23 May 2023

Roland Ryndzionek, Michal Michna, Filip Kutt, Grzegorz Kostro and Krzysztof Blecharz

The purpose of this paper is to provide an analysis of the performance of a new five-phase doubly fed induction generator (DFIG).

Abstract

Purpose

The purpose of this paper is to provide an analysis of the performance of a new five-phase doubly fed induction generator (DFIG).

Design/methodology/approach

This paper presents the results of a research work related to five-phase DFIG framing, including the development of an analytical model, FEM analysis as well as the results of laboratory tests of the prototype. The proposed behavioral level analytical model is based on the winding function approach. The developed DFIG model was used at the design stage to simulate the generator’s no-load and load state. Then, the results of the FEM analysis were shown and compared with the results of laboratory tests of selected DFIG operating states.

Findings

The paper provides the results of analytical and FEM simulation and measurement tests of the new five-phase dual-feed induction generator. The use of the MATLAB Simscape modeling language allows for easy and quick implementation of the model. Design assumptions and analytical model-based analysis have been verified using FEM analysis and measurements performed on the prototype. The results of the presented research validate the design process as well as show the five-phase winding design advantage over the three-phase solution regarding the control winding power quality.

Research limitations/implications

The main disadvantage of the winding function approach-based model development is the simplification regarding omitting the tangential airgap flux density component. However, this fault only applies to large airgap machines and is insignificant in induction machines. The results of the DFIG analyses were limited to the basic operating states of the generator, i.e. the no-load state, the inductive and resistive load.

Practical implications

The novel DFIG with five phase rotor control winding can operate as a regular three-phase machine in an electric power generation system and allows for improved control winding power quality of the proposed electrical energy generation system. This increase in power quality is due to the rotor control windings inverter-based PWM supply voltage, which operates with a wider per-phase supply voltage range than a three-phase system. This phenomenon was quantified using control winding current harmonic analysis.

Originality/value

The paper provides the results of analytical and FEM simulation and measurement tests of the new five-phase dual-feed induction generator.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 42 no. 4
Type: Research Article
ISSN: 0332-1649

Keywords

Open Access
Article
Publication date: 29 July 2020

Ghoulemallah Boukhalfa, Sebti Belkacem, Abdesselem Chikhi and Said Benaggoune

This paper presents the particle swarm optimization (PSO) algorithm in conjuction with the fuzzy logic method in order to achieve an optimized tuning of a proportional integral…

1191

Abstract

This paper presents the particle swarm optimization (PSO) algorithm in conjuction with the fuzzy logic method in order to achieve an optimized tuning of a proportional integral derivative controller (PID) in the DTC control loops of dual star induction motor (DSIM). The fuzzy controller is insensitive to parametric variations, however, with the PSO-based optimization approach we obtain a judicious choice of the gains to make the system more robust. According to Matlab simulation, the results demonstrate that the hybrid DTC of DSIM improves the speed loop response, ensures the system stability, reduces the steady state error and enhances the rising time. Moreover, with this controller, the disturbances do not affect the motor performances.

Details

Applied Computing and Informatics, vol. 18 no. 1/2
Type: Research Article
ISSN: 2634-1964

Keywords

Open Access
Article
Publication date: 23 September 2022

Katharina Jahn, Frederike Marie Oschinsky, Bastian Kordyaka, Alla Machulska, Tanja Joan Eiler, Armin Gruenewald, Tim Klucken, Rainer Brueck, Carl Friedrich Gethmann and Bjoern Niehaves

Immersive virtual reality (IVR) has been frequently proposed as a promising tool for learning. However, researchers have commonly implemented a plethora of design elements in…

995

Abstract

Purpose

Immersive virtual reality (IVR) has been frequently proposed as a promising tool for learning. However, researchers have commonly implemented a plethora of design elements in these IVR systems, which makes the specific aspects of the system that are necessary to achieve beneficial outcomes unclear. Against this background, this study aims to combine the literature on presence with learning theories to propose that the ability of IVR to present 3D objects to users improves the presence of these objects in the virtual environment compared with 2D objects, leading to increased learning performance.

Design/methodology/approach

To test this study’s hypotheses, the authors conducted a 2 (training condition: approach vs avoid) x 2 (object presence: high vs low) between-subjects laboratory experiment that used IVR with 83 female participants.

Findings

The results support this study’s hypotheses and show that training with high object presence leads to greater reactions to cues (chocolate cravings) and improved health behaviour (chocolate consumption).

Originality/value

This study shows that increased object presence leads to unique experiences for users, which help reinforce training effects. Moreover, this work sheds further light on how immersive computer technologies can affect user attitudes and behaviour. Specifically, this work contributes to IVR research by showing that learning effects can be enhanced through an increased degree of object presence.

Details

Internet Research, vol. 32 no. 7
Type: Research Article
ISSN: 1066-2243

Keywords

Open Access
Article
Publication date: 5 June 2020

Zijun Jiang, Zhigang Xu, Yunchao Li, Haigen Min and Jingmei Zhou

Precise vehicle localization is a basic and critical technique for various intelligent transportation system (ITS) applications. It also needs to adapt to the complex road…

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Abstract

Purpose

Precise vehicle localization is a basic and critical technique for various intelligent transportation system (ITS) applications. It also needs to adapt to the complex road environments in real-time. The global positioning system and the strap-down inertial navigation system are two common techniques in the field of vehicle localization. However, the localization accuracy, reliability and real-time performance of these two techniques can not satisfy the requirement of some critical ITS applications such as collision avoiding, vision enhancement and automatic parking. Aiming at the problems above, this paper aims to propose a precise vehicle ego-localization method based on image matching.

Design/methodology/approach

This study included three steps, Step 1, extraction of feature points. After getting the image, the local features in the pavement images were extracted using an improved speeded up robust features algorithm. Step 2, eliminate mismatch points. Using a random sample consensus algorithm to eliminate mismatched points of road image and make match point pairs more robust. Step 3, matching of feature points and trajectory generation.

Findings

Through the matching and validation of the extracted local feature points, the relative translation and rotation offsets between two consecutive pavement images were calculated, eventually, the trajectory of the vehicle was generated.

Originality/value

The experimental results show that the studied algorithm has an accuracy at decimeter-level and it fully meets the demand of the lane-level positioning in some critical ITS applications.

Details

Journal of Intelligent and Connected Vehicles, vol. 3 no. 2
Type: Research Article
ISSN: 2399-9802

Keywords

Open Access
Article
Publication date: 26 June 2021

Chunhui Liu and Huawei Zheng

Low-carbon agricultural technology (LAT) extension is a key strategy for the agricultural sector to address climate change. Social capital, which consists of social networks…

1256

Abstract

Purpose

Low-carbon agricultural technology (LAT) extension is a key strategy for the agricultural sector to address climate change. Social capital, which consists of social networks, trust and norms, can play an active LAT extension role. This paper aims to analyze the mechanism of the role of social capital in the process of LAT extension.

Design/methodology/approach

Questionnaire data from six counties in Jiangsu, China, were used to measure social capital and analyze its effect on LAT extension using logistic regression. Data from 27 interviews were used to analyze the LAT extension experiences and problems.

Findings

LAT is mainly deployed by the government to farmers and distributed among them. In this process, the village officials who form parts of the government’s composition and the villagers play a dual role that facilitates a close link between them and the farmers and ensures LAT integration. However, social norms did not play a significant role in the process.

Practical implications

Farmers’ acceptance of LAT is based solely on the trade-off between local networks’ benefits and trust in local villagers and village officials. LAT-related laws and technical measures, thus are essential to strengthen LAT practices’ authority and incorporate LAT-based agricultural production as the norm of production behavior.

Originality/value

This paper provides an insight into the process and essence of farmers’ acceptance of LAT, which provides theoretical lessons for the LAT extension in China and indeed other developing countries.

Details

International Journal of Climate Change Strategies and Management, vol. 13 no. 3
Type: Research Article
ISSN: 1756-8692

Keywords

Open Access
Article
Publication date: 29 November 2023

Daniel Kipkirong Tarus and Fiona Jepkosgei Korir

This paper examines how board structure influences real earnings management and the interaction effect of CEO narcissism on board structure-real earnings management relationship.

Abstract

Purpose

This paper examines how board structure influences real earnings management and the interaction effect of CEO narcissism on board structure-real earnings management relationship.

Design/methodology/approach

The authors used panel data derived from secondary sources from publicly listed firms in Kenya during 2002–2017. Hierarchical regression analysis was used to test the hypotheses.

Findings

The results indicate that board independence, board tenure and size have significant negative effect on real earnings management, while CEO duality positively affects real earnings management. Further, the interaction results show that CEO narcissism moderates the relationship between CEO duality and real earnings management.

Research limitations/implications

The results suggest that real earnings management reduces when boards are independent, large and comprising of long-tenured members. However, when the CEO plays dual role of a chairman, real earnings management increases. The authors also find that when CEOs are narcissists, the monitoring role of the board is compromised.

Originality/value

The study adds value to the understanding of how board structure and CEO narcissism influence the monitoring role of the board among firms listed at Nairobi Securities Exchange.

Details

PSU Research Review, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2399-1747

Keywords

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