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Article
Publication date: 5 January 2024

Neslihan Arslan and Eda Köksal

The goal of this narrative review was to look at the link between the Mediterranean diet (MD) and the telomere length. Furthermore, this study aims to understand the impact of the…

Abstract

Purpose

The goal of this narrative review was to look at the link between the Mediterranean diet (MD) and the telomere length. Furthermore, this study aims to understand the impact of the MD on obesity-related telomere length.

Design/methodology/approach

Relevant literature was reviewed to explore the potential influence of the MD on telomere length and its association with obesity.

Findings

The MD is one of the healthiest diets of all known dietary patterns, and it is also linked to the telomere length. Except for fruits and vegetables, the main findings for other MD components are inconsistent. In terms of antioxidant and antiinflammatory properties, using the MD as a weight loss approach is a good method. For predicting changes in obesity characteristics, the initial telomere length is critical. However, there are not many studies in the field that have looked at the MD as a weight loss approach and its link to the telomere length. As a result, more research is needed to understand these connections in various groups.

Originality/value

This study is unique since it examines the MD, telomere length and obesity-related consequences. This study examines the MD, telomere length and obesity to determine if the MD can help lose weight while maintaining telomere length. As there are few studies on MD weight loss and telomere length, the work emphasizes the need for greater research in this area. This study fills a research gap and improves the understanding of nutrition, telomere biology and obesity-related outcomes.

Details

Nutrition & Food Science , vol. 54 no. 2
Type: Research Article
ISSN: 0034-6659

Keywords

Article
Publication date: 29 April 2022

Taposh Kumar Roy and Md Habibullah

Predictive current control (PCC) of three-to-five-phase direct matrix converters (DMCs) is computationally expensive. For this reason, this study aims to consider a reduced number…

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Abstract

Purpose

Predictive current control (PCC) of three-to-five-phase direct matrix converters (DMCs) is computationally expensive. For this reason, this study aims to consider a reduced number of switching states of DMC in PCC algorithm to predict the control objectives, such as output current control and input reactive power control.

Design/methodology/approach

The switching sequences which yield the voltage vectors of variable amplitude at a constant frequency in space are considered for the prediction and optimization step of PCC algorithm. For the selected voltage vectors, the phase angles of the output vectors are independent on the phase angles of the input vectors. In a three-to-five-phase DMC, there are 243 valid switching states. Among the switching states, only 91 states are considered using the aforementioned concept of variable amplitude output at a constant frequency. This reduced number of switching states simplifies the computational complexity of MPC based current control of three-to-five-phase DMC.

Findings

The computational complexity of the proposed PCC based DMC is lower than the all 243 vectors based PCC. The current total harmonic distortion, transient current response and input reactive power control for the simplified 91 vector based PCC are similar to the all 243 vectors based PCC.

Originality/value

A reduced number of switching sequence is considered for the prediction and optimization step of PCC algorithm. Hence, PCC algorithm can be sampled at a high frequency in real-time applications. Then, the performance of the PCC will be improved.

Details

World Journal of Engineering, vol. 20 no. 5
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 30 March 2022

Karthick R., Ramakrishnan C. and Sridhar S.

This paper aims to introduce the quasi impedance source inverter (qZSI)-based static compensator (STATCOM), which is incorporated into the hybrid distributed power generation…

Abstract

Purpose

This paper aims to introduce the quasi impedance source inverter (qZSI)-based static compensator (STATCOM), which is incorporated into the hybrid distributed power generation system for enhancement of power quality. The distributed power generation system includes the photovoltaic (PV), wind energy conversion system (WECS) and battery energy storage system.

Design/methodology/approach

The WECS is used by the self-excited induction generator (SEIG) and the flywheel energy storage system (FESS). To regulate its terminal voltage and frequency, the SEIG requires adjustable volt-ampere reactive (VAR). A combination of a STATCOM and a fixed condenser bank usually serves to satisfy the VAR demand. The maximum correntropy criterion-based adaptive filter technique (AFT) is proposed to control the qZSI-STATCOM and to guarantee that the voltage at the SEIG terminal is harmonic-free while providing non-linear three-phase and single-phase loads.

Findings

The coordinated operation of the suggested voltage control and flywheel control systems ensures that load voltage and frequency are retained in their respective values at very low harmonic distortions regardless of wind speed and load variation. The simulation and experimental studies are carried out under different load conditions to validate the efficiencies of the PV-assisted STATCOM.

Originality/value

To improve system stability and minimize total costs, extra load current sensors can also be avoided. This paper proposes to control the SEIG terminal voltage and harmonic elimination in the standalone WECS systems using maximum correntropy criterion-based AFT with a fuzzy logic controller.

Article
Publication date: 6 March 2024

Mouna Zerzeri, Intissar Moussa and Adel Khedher

The purpose of this paper aims to design a robust wind turbine emulator (WTE) based on a three-phase induction motor (3PIM).

Abstract

Purpose

The purpose of this paper aims to design a robust wind turbine emulator (WTE) based on a three-phase induction motor (3PIM).

Design/methodology/approach

The 3PIM is driven by a soft voltage source inverter (VSI) controlled by a specific space vector modulation. By adjusting the appropriate vector sequence selection, the desired VSI output voltage allows a real wind turbine speed emulation in the laboratory, taking into account the wind profile, static and dynamic behaviors and parametric variations for theoretical and then experimental analysis. A Mexican hat profile and a sinusoidal profile are therefore used as the wind speed system input to highlight the electrical, mechanical and electromagnetic system response.

Findings

The simulation results, based on relative error data, show that the proposed reactive power control method effectively estimates the flux and the rotor time constant, thus ensuring an accurate trajectory tracking of the wind speed for the wind emulation application.

Originality/value

The proposed architecture achieves its results through the use of mathematical theory and WTE topology combine with an online adaptive estimator and Lyapunov stability adaptation control methods. These approaches are particularly relevant for low-cost or low-power alternative current (AC) motor drives in the field of renewable energy emulation. It has the advantage of eliminating the need for expensive and unreliable position transducers, thereby increasing the emulator drive life. A comparative analysis was also carried out to highlight the online adaptive estimator fast response time and accuracy.

Details

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

Keywords

Article
Publication date: 2 January 2024

Tim Gruchmann, Gernot M. Stadtfeld, Matthias Thürer and Dmitry Ivanov

Experiencing more frequent, system-wide disruptions, such as pandemics and geopolitical conflicts, supply chains can be largely destabilized by a lack of materials, services or…

Abstract

Purpose

Experiencing more frequent, system-wide disruptions, such as pandemics and geopolitical conflicts, supply chains can be largely destabilized by a lack of materials, services or components. Supply chain resilience (SCRES) constitutes the network ability to recover after and survive during such unexpected events. To enhance the understanding of SCRES as a system-wide quality, this study tests a comprehensive SCRES model with data from multiple industries.

Design/methodology/approach

The study proposes a theoretical framework conceptualizing SCRES as system quality, extending the classical proactive/reactive taxonomy by multiple system states consisting of the supply system properties, behaviors and responses to disruptions. Underlying hypotheses were tested using an online survey. The sample consists of 219 responses from German industries. Maximum likelihood structural equation modeling (ML-SEM) and moderation analysis were used for analyzing the survey data. The study was particularly designed to elaborate on supply chain theory.

Findings

Two pathways of parallel SCRES building were identified: proactive preparedness via anticipation and reactive responsiveness via agility. Both system responses are primarily built simultaneously rather than successively. The present study further provides empirical evidence on the central role of visibility and velocity in achieving comprehensive SCRES, while flexibility only exerts short-term support after a disruption. The study additionally points to potential “spillover effects” such as the vital role of proactive SCRES in achieving reactive responsiveness.

Originality/value

The present study confirms and expands existing theories on SCRES. While stressing the multidimensionality of SCRES, it theorizes the (inter-)temporal evolution of a system and offers practical guidelines for SCRES building in various industrial contexts. It thus supports the transformation toward more resilient and viable supply chains, contributing to the increasing efforts of middle-range theory building to achieve an overarching theory. The study also points to potential future research avenues.

Details

International Journal of Physical Distribution & Logistics Management, vol. 54 no. 1
Type: Research Article
ISSN: 0960-0035

Keywords

Article
Publication date: 15 April 2024

Ann Wairimu Mburu, David Githinji Njuguna, Fredrick Musieba, Charles Nzila, Virginia Kimani and Alice Wangai

The purpose of this paper is to investigate the efficacy of bacterial exopolysaccharides (Eps) in reactive black 5 (RB5) textile dye wastewater bioremediation.

Abstract

Purpose

The purpose of this paper is to investigate the efficacy of bacterial exopolysaccharides (Eps) in reactive black 5 (RB5) textile dye wastewater bioremediation.

Design/methodology/approach

The Eps were produced by bacteria isolated from cotton gin trash soils collected from different cotton-growing regions in Kenya for comparison purposes. A broth medium reconstituted using molasses was assessed for its capacity to produce the Eps. RB5 textile dye wastewater was optimized for dye removal under different temperatures, times and molasses concentrations. Dye removal was studied by Lovibond-Day Light Comparator, UV–Vis spectrophotometer and FTIR.

Findings

It was found that cotton gin trash soils contained Eps-producing bacteria. Three of the Eps studied were found to have the capacity to remove at least 80% of the dye from the wastewater.

Research limitations/implications

This research did not assess the efficacy of the RB5 dye removal from the wastewater by mixtures of the Eps.

Practical implications

Bioremediation of textile dye wastewater with Eps produced by bacteria cultured from cotton gin trash soil is significant because it will offer an effective and cleaner alternative to the chemical coagulants.

Social implications

Alternative treatment of textile wastewater with the Eps would result in safer water being released into the water bodies as opposed to the chemically treated wastewater that contains remnant chemicals.

Originality/value

Research on the use of Eps produced by bacteria isolated from cotton gin trash soils for removal of RB5 dye from textile wastewater has not been done before.

Details

Research Journal of Textile and Apparel, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1560-6074

Keywords

Article
Publication date: 19 December 2023

Seda Özcan, Bengü Sevil Oflaç, Sinem Tokcaer and Özgür Özpeynirci

The criticality of late deliveries in transportation lies in the threat of considerable multi-level supply chain costs. This study aims to reveal the dynamic capabilities playing…

Abstract

Purpose

The criticality of late deliveries in transportation lies in the threat of considerable multi-level supply chain costs. This study aims to reveal the dynamic capabilities playing a facilitating role in preventing delay, thus providing timely delivery, as well as developing an understanding of how and when those capabilities are activated within the supply chain network.

Design/methodology/approach

An exploratory study was conducted involving 16 semi-structured expert interviews with the representatives of logistics service providers and shippers. Following an interpretive phenomenology framework, the prevention phenomenon was explained.

Findings

Findings revealed two preventive capability categories in delay prevention: (1) proactive capabilities, referring to the enabling actions planned before departure, and (2) reactive capabilities, referring to actions planned after departure. Findings pinpoint that, in addition to the proactive capabilities, reactive capabilities enabled by innovative problem-solving actions are crucial for adapting to a dynamically changing environment in prevention. Moreover, this study shows that prevention capabilities are characterized by tangible and intangible resources and integration of resources with external links which constitute a delay prevention network within a wider service ecosystem.

Originality/value

This study stands out with its specific focus on delay prevention capabilities and enabling actions from the perspectives of logistics service providers and shippers. The premises of the resource-based view are combined with dynamic capabilities theory, leading to a proposed time-based taxonomy of proactive and reactive capabilities in supply chains, aimed at creating value and strengthening resilience.

Details

The International Journal of Logistics Management, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0957-4093

Keywords

Article
Publication date: 25 August 2023

Matthew C. McParker

Preservice teachers (PSTs) typically have few opportunities to observe social studies instruction in PSTs' elementary field placements. To practice effective integration as a…

Abstract

Purpose

Preservice teachers (PSTs) typically have few opportunities to observe social studies instruction in PSTs' elementary field placements. To practice effective integration as a pathway to include more social studies instruction, PSTs developed a unit plan based on inquiry during an undergraduate methods course. The purpose of this study was to explore what scaffolds were effective in PSTs' development of social studies inquiry projects.

Design/methodology/approach

The author used a multiple case study approach, examining initial submissions, feedback and resubmissions as PSTs developed PSTs' inquiry projects. The data were analyzed with an eye on PSTs' ability to plan a unit according to the four dimensions of the C3 Framework's inquiry arc (National Council for the Social Studies [NCSS], 2013).

Findings

The author analyzed data related to PSTs’ area of highest need from PSTs' initial submissions: staging the task, formative tasks and resources. PSTs were able to develop inquiry projects after being supported in their (1) organization, (2) clarity, (3) alignment and (4) developmental appropriateness.

Originality/value

This study shows that novice teachers can create high-quality social studies learning experiences in elementary school when provided appropriate supports (in this case, feedback about organization, clarity, alignment and developmental appropriateness). With the tools to develop such projects, new teachers may be able to increase the amount of social studies taught in elementary classrooms.

Details

Social Studies Research and Practice, vol. 18 no. 3
Type: Research Article
ISSN: 1933-5415

Keywords

Article
Publication date: 26 January 2023

Emilia Vann Yaroson, Liz Breen, Jiachen Hou and Julie Sowter

This study aims to explore the effect of power-based behaviours on pharmaceutical supply chain (PSC) resilience.

Abstract

Purpose

This study aims to explore the effect of power-based behaviours on pharmaceutical supply chain (PSC) resilience.

Design/methodology/approach

This study used a mixed-method approach to explore the role of power-based behaviours in PSC resilience. Qualitative interviews from 23 key PSC stakeholders, followed by thematic analysis, revealed the underlying perceptions regarding PSC resilience. Quantitative propositions were then developed based on the themes adopted from PSC resilience literature and the qualitative findings. These were tested via a survey questionnaire administered to 106 key stakeholders across the various levels in the PSC. Structural equation modelling with partial least squares was used to analyse the data.

Findings

The data analysed identified proactive and reactive strategies as resilience strategies in the PSC. However, power-based behaviours represented by quota systems, information and price control influenced these resilience strategies. From a complex adaptive system (CAS) perspective, the authors found that when power-based behaviours were exhibited, the interactions between PSC actors were mixed. There was a negative influence on reactive strategies and a positive influence on proactive strategies. The analysis also showed that PSC complexities measured by stringent regulations, long lead times and complex production moderated the effect of power-based behaviour on reactive strategies. Thus, the negative impact of power-based behaviours on reactive strategies stemmed from PSC complexities.

Research limitations/implications

This research particularly reveals the role of power-based behaviours in building PSC resilience. By evaluating the nexus from a CAS perspective, the analysis considered power-based behaviours and the moderating role of PSC complexities in developing resilience strategies. This study considers the interactions of PSC actors. This study shows that power asymmetry is a relational concept that inhibits the efficacy of reactive strategies. This study thus advocates the importance of power in achieving a more resilient PSC from a holistic perspective by highlighting the importance of the decision-making process among supply chain (SC) partners. The findings are particularly relevant if PSC resilience is viewed as a CAS. All the interactions and decision-making processes affect outcomes because of their inherent complexities. Although this study focused on the PSC, its implications could be extended to other SCs.

Practical implications

The authors identified that power-based behaviours influenced resilience strategies. It was detrimental to reactive strategies because of the complexities of the PSC but beneficial to proactive strategies through resource-sharing. PSC actors are therefore encouraged to pursue proactive strategies as this may aid in mitigating the impact of disruptions. However, power-based behaviours bred partner dissatisfaction. This dissatisfaction may occur even within strategic alliances indicating that power could be detrimental to proactive strategies. Therefore, it is pertinent to identify conditions that lead to dissatisfaction when pursuing strategic partnerships. This study provides insight into actual behaviours influencing resilience and quantifies their effects on the PSC. These insights will be valuable for all SC partners wanting to improve their resilience strategies.

Originality/value

Previous PSC management and resilience studies have not examined the role of power in building resilience in the PSC. This paper thus provides a unique contribution by identifying the role of power in PSC resilience, offers empirical evidence and a novel theoretical perspective for future practice and research in building PSC resilience strategies.

Details

Supply Chain Management: An International Journal, vol. 28 no. 4
Type: Research Article
ISSN: 1359-8546

Keywords

Article
Publication date: 8 September 2022

Yildiz Kose, Suleyman Muftuoglu, Emre Cevikcan and Mehmet Bulent Durmusoglu

Autonomous maintenance (AM), one of the pillars of total productive maintenance (TPM), aims to achieve performance toward zero defects and zero breakdowns. AM system equipped with…

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Abstract

Purpose

Autonomous maintenance (AM), one of the pillars of total productive maintenance (TPM), aims to achieve performance toward zero defects and zero breakdowns. AM system equipped with comprehensive lean tools provides continuous improvement during the AM activities. Despite its long duration, establishing a lean AM system with a robust guideline would provide significant benefits such as high quality and short lead time. Therefore, AM design approach should be provided in a holistic and detailed manner. This study aims to develop a framework for AM design, including preliminary, reactive, preventive and proactive steps using the axiomatic design (AD).

Design/methodology/approach

Requirements and technical parameters of the AM system are explored with AD. An extensive literature review and a real-life application are presented.

Findings

The proposed design was validated by adapting the proposed roadmap to a textile manufacturing system in Turkey. The application results justify the established AM system design with an average downtime improvement of 69.2% and the average elapsed time between two failures improvement of 65.1% for apparel department.

Originality/value

This study has the novelty of establishing an overall AM system design with all of its stages stepwise. It presents a comprehensive guideline in terms of integration of lean philosophy into AM design by generating maintenance-related use cases for lean tools. The developed approach facilitates creating and analyzing complex systems to improve maintenance implementations while reducing nonvalue-added operations.

Details

International Journal of Lean Six Sigma, vol. 14 no. 3
Type: Research Article
ISSN: 2040-4166

Keywords

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