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Article
Publication date: 12 June 2020

Amirreza Kosari, Alireza Sharifi, Alireza Ahmadi and Masoud Khoshsima

Attitude determination and control subsystem (ADCS) is a vital part of earth observation satellites (EO-Satellites) that governs the satellite’s rotational motion and pointing. In…

230

Abstract

Purpose

Attitude determination and control subsystem (ADCS) is a vital part of earth observation satellites (EO-Satellites) that governs the satellite’s rotational motion and pointing. In designing such a complicated sub-system, many parameters including mission, system and performance requirements (PRs), as well as system design parameters (DPs), should be considered. Design cycles which prolong the time-duration and consequently increase the cost of the design process are due to the dependence of these parameters to each other. This paper aims to describe a rapid-sizing method based on the design for performance strategy, which could minimize the design cycles imposed by conventional methods.

Design/methodology/approach

The proposed technique is an adaptation from that used in the aircraft industries for aircraft design and provides a ball-park figure with little engineering man-hours. The authors have shown how such a design technique could be generalized to cover the EO-satellites platform ADCS. The authors divided the system requirements into five categories, including maneuverability, agility, accuracy, stability and durability. These requirements have been formulated as functions of spatial resolution that is the highest level of EO-missions PRs. To size, the ADCS main components, parametric characteristics of the matching diagram were determined by means of the design drivers.

Findings

Integrating the design boundaries based on the PRs in critical phases of the mission allowed selecting the best point in the design space as the baseline design with only two iterations. The ADCS of an operational agile EO-satellite is sized using the proposed method. The results show that the proposed method can significantly reduce the complexity and time duration of the performance sizing process of ADCS in EO-satellites with an acceptable level of accuracy.

Originality/value

Rapid performance sizing of EO-satellites ADCS using matching diagram technique and consequently, a drastic reduction in design time via minimization of design cycles makes this study novel and represents a valuable contribution in this field.

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Article
Publication date: 12 December 2024

Reza Aalikhani, Mohammad Reza Rasouli, Hossein Ghanbari, Mohammad Fathian and Alireza Ali ahmadi

Interorganizational collaborations are crucial for delivering high-quality, integrated healthcare services. To maximize the benefits of these collaborative networks, effective…

20

Abstract

Purpose

Interorganizational collaborations are crucial for delivering high-quality, integrated healthcare services. To maximize the benefits of these collaborative networks, effective governance structures and mechanisms must be in place. While previous studies have extensively examined organizational-level factors, such as partner capabilities and backgrounds, this study focuses on network-level factors, including collaboration structures and tie characteristics that shape effective network governance.

Design/methodology/approach

A systematic literature review (SLR) was conducted to identify and synthesize the key network-level factors influencing governance structures and mechanisms in healthcare networks.

Findings

The review identified 22 critical factors, categorized into three primary groups that impact network governance. These findings offer a robust foundation for developing context-sensitive governance models tailored to healthcare systems.

Practical implications

This study provides valuable insights for healthcare practitioners, policymakers and researchers by highlighting key factors that can improve interorganizational collaboration within healthcare systems. The findings contribute to both theory and practice, with the potential to enhance healthcare service delivery and patient outcomes.

Originality/value

This study is the first to systematically identify and categorize the network-level factors that influence governance structures and mechanisms in healthcare networks, providing a comprehensive and novel contribution to the field.

Details

Journal of Health Organization and Management, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1477-7266

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Article
Publication date: 20 September 2024

Muhammad Abid, Syed Muhammad Fazal e Hasan, Hormoz Ahmadi, Alireza Amrollahi and Gary Mortimer

This study employs a multi-method approach to investigate how perceived relationship marketing investment affects perceived relationship value and consumer gratitude, influencing…

155

Abstract

Purpose

This study employs a multi-method approach to investigate how perceived relationship marketing investment affects perceived relationship value and consumer gratitude, influencing consumer involvement, word-of-mouth intentions, and long-term relationships across three retail consumer types.

Design/methodology/approach

The study analyses a model involving 542 consumers, employing structural equation modeling and fuzzy-set qualitative comparative analysis to identify distinctive factor configurations across public, semi-public, and private retail organizations.

Findings

A retailer’s investment in relationship marketing significantly enhances relationship value and consumer gratitude, leading to increased engagement and word-of-mouth intentions. Perceived benevolence moderates the effect of relationship marketing on gratitude. However, gratitude alone does not ensure long-term relationships. Using fsQCA, we identify four distinct consumer configurations, providing nuanced insights.

Research limitations/implications

Retail organizations broaden relationship marketing strategies to boost perceived value and elicit consumer gratitude, influencing consumer performance outcomes.

Practical implications

Retail organizations should broaden relationship marketing strategies to boost perceived value and elicit consumer gratitude, influencing consumer performance outcomes.

Social implications

Managers should develop strategies that lead to consumer gratitude toward the firm, such as journey mapping can help visualize retail delivery. Grateful consumers may contribute to firms’ profitability by influencing current and potential consumers in their social networks and communicating their expertise through review/feedback for improvement. Therefore, various strategies are needed to stimulate positive comments from grateful consumers about the firm’s excellent performance.

Originality/value

This study builds on Lawler’s affect theory, highlighting how relationship value and consumer gratitude profoundly influence exchange process outcomes. It introduces new psychological mechanisms to explain the impact of perceived relationship marketing investment on performance outcomes. Integrating these elements provides a comprehensive understanding of retailer–consumer dynamics, revealing how emotional and psychological factors shape marketing strategies and business performance. This contribution enriches theoretical frameworks and offers practical insights for enhancing relationship marketing practices.

Details

International Journal of Retail & Distribution Management, vol. 52 no. 12
Type: Research Article
ISSN: 0959-0552

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Article
Publication date: 27 November 2024

Taher Ahmadi, Alireza F. Hesaraki and Jan P.M. Morsch

In an era where global supply chains are increasingly susceptible to disruptions, this study aims to unlock the potential of IT integration within the supply chain in enhancing…

196

Abstract

Purpose

In an era where global supply chains are increasingly susceptible to disruptions, this study aims to unlock the potential of IT integration within the supply chain in enhancing supply chain resilience. It investigates how this integration, combined with IT-driven capabilities, acts as a cornerstone in strengthening supply chain resilience (SCRs). The research navigates through the intricate dynamics of supply chain management to chart a strategic pathway for managers, illuminating the investments necessary to cultivate a resilient supply chain.

Design/methodology/approach

Grounding their investigation within the theoretical lens of dynamic resource-based theory, the authors designed a conceptual model to investigate the relationship between IT integration and SCR. Through the survey responses from supply chain professionals, the authors applied partial least squares-based structural equation modelling (PLS-SEM) to unravel the complexities of building a resilient supply chain.

Findings

Their investigation reveals that IT-driven supply chain capabilities (SCCs) are not just beneficial but essential in bridging IT integration with SCR. These capabilities emerge as vital, fully mediating the relationship between IT integration and SCR. Moreover, the significance of robust supply chain risk management (SCRM) in harnessing these IT-driven capabilities to bolster resilience is undeniable, offering organisations a sustainable advantage during times of turbulence.

Research limitations/implications

The primary limitation of this study is that data collection occurred during the COVID-19 pandemic. Therefore, the results may not be representative of different circumstances or periods. This study uncovered several noteworthy findings. The authors found that SCCs fully mediate the relationship between Supply Chain Management IT Integration (SCMITI) and SCR. In addition, the authors found that SCRM positively moderates the relationship between SCMITI and SCCs. The authors observed that Supply Chain Structural Complexity (SCSC) has no significant moderating effect on the relationship between IT-driven SCCs and SCR.

Practical implications

The results of this study offer managers a clear path forward for investing in SCR. Businesses must invest in SCMITI and SCRM to boost their SCR through developing IT-driven SCCs to ensure consistent business continuity. SCMITI does not necessarily increase SCR resilience when it is done poorly and does not lead to SCCs effectively. In this regard, managers must rely on collective wisdom to determine which technologies and IT applications will best meet their business needs and their peers’ requirements in the supply chain.

Originality/value

This study sheds light on the mechanisms through which IT enhances SCR. It fills a critical knowledge gap, focusing on the synergy between IT integration, risk management and the cultivation of IT-driven capabilities to navigate supply chain disruptions.

Details

Supply Chain Management: An International Journal, vol. 30 no. 1
Type: Research Article
ISSN: 1359-8546

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Article
Publication date: 17 August 2010

Alireza Ahmadi, Peter Söderholm and Uday Kumar

The purpose of this paper is to present issues and challenges of scheduled maintenance task development within the maintenance review board (MRB) process, and to find potential…

3581

Abstract

Purpose

The purpose of this paper is to present issues and challenges of scheduled maintenance task development within the maintenance review board (MRB) process, and to find potential areas of improvement in the application of the MSG‐3 methodology for aircraft systems.

Design/methodology/approach

The issues and challenges as well as potential areas of improvement have been identified through a constructive review that consists of two parts. The first part is a benchmarking between the Maintenance Steering Group (MSG‐3) methodology and other established and documented versions of reliability‐centred maintenance (RCM). This benchmarking focuses on the MSG‐3 methodology and compares it with some RCM standards to identify differences and thereby find ways to facilitate the application of MSG‐3. The second part includes a discussion about methodologies and tools that can support different steps of the MSG‐3 methodology within the framework of the MRB process.

Findings

The MSG‐3 methodology is closely related to the RCM methodology, in which the anticipated consequences of failure are considered for risk evaluation. However, MSG‐3 considers neither environmental effects of failures nor operational consequences of hidden failures. Furthermore, in MSG‐3, the operational check (failure‐finding inspection) is given priority before all other tasks, whereas in RCM it is considered as a default action, where there is no other applicable and effective option. While RCM allows cost‐effectiveness analysis for all failures that have no safety consequences, MSG‐3 just allows it for failures with economic consequences. A maintenance program that is established through the MRB process fulfils the requirements of continuous airworthiness, but there is no foundation to claim that it is the optimal or the most effective program from an operator's point‐of‐view. The major challenge when striving to achieve a more effective maintenance program within the MRB process is to acquire supporting methodologies and tools for adequate risk analysis, for optimal interval assignments, and for selection of the most effective maintenance task.

Originality/value

The paper presents a critical review of existing aircraft scheduled maintenance program development methodologies, and demonstrates the differences between MSG‐3 and other RCM methodologies.

Details

Journal of Quality in Maintenance Engineering, vol. 16 no. 3
Type: Research Article
ISSN: 1355-2511

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Article
Publication date: 11 August 2022

Emad Kazemzadeh, Mohammad Taher Ahmadi Shadmehri, Taghi Ebrahimi Salari, Narges Salehnia and Alireza Pooya

One of the most important ways to pay attention to sustainable economic development is to invest in green technology and alter the energy consumption structure (ECS) in countries…

127

Abstract

Purpose

One of the most important ways to pay attention to sustainable economic development is to invest in green technology and alter the energy consumption structure (ECS) in countries. Changing the ECS can be important in two ways: first, it increases the diversity of energy consumption and reduces energy dependence on other countries. Second, the use of highly polluted nonrenewable energy sources (such as oil and coal) is reduced, leading to the transfer of energy to natural gas with less carbon emissions or renewable energy. To this end, the authors examined the asymmetric effects of eco-innovation on the US ECS from 1980 to 2019. This paper aims to address this issue.

Design/methodology/approach

In this research, the nonlinear autoregressive distributed lag (ARDL) (NARDL) model is used and the results are compared with the linear ARDL model.

Findings

The ARDL results also confirm the positive effects of oil prices and GDP per capita in the long run. On the other hand, short-term and long-term Wald test results confirm the nonlinear effects of eco-innovation (LPATENT) on US ECS. These results indicate that 1% positive shock in LPATENTˆ+ increases the ECS by 0.179, while 1% negative fluctuations (LPATENTˆ-) leads to a decrease (−0.085) in the ECS. However, the ARDL results, in general, show the positive effects of LPATENT on the ECS in long run. Evidence suggests that ignoring nonlinear effects can lead to inaccurate results. Policy suggestions for environmental technology innovation are presented in the results.

Originality/value

This research has innovations in various aspects so that the previous studies in this field have examined the effects of environmental innovation on renewable or nonrenewable energy consumption, and so far no study has been done on the ECS. In this research, the Shannon–Wiener index has been used to calculate the ECS.

Details

Management of Environmental Quality: An International Journal, vol. 34 no. 1
Type: Research Article
ISSN: 1477-7835

Keywords

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Expert briefing
Publication date: 29 February 2016

In both polls, hardline conservative candidates were ousted in Tehran, the most important electoral district.

Details

DOI: 10.1108/OXAN-DB209693

ISSN: 2633-304X

Keywords

Geographic
Topical
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Article
Publication date: 9 April 2018

Masoud Morvarid, Ali Rezghi, Alireza Riasi and Mojtaba Haghighi Yazdi

Analysis of fast transient flow in water pipe systems is an important issue for the prevention of unfavorable pressure oscillations and severe damage to the pipelines. This paper…

183

Abstract

Purpose

Analysis of fast transient flow in water pipe systems is an important issue for the prevention of unfavorable pressure oscillations and severe damage to the pipelines. This paper aims to present the performance of three-dimensional (3D) simulation of laminar water hammer caused by fast closure of valve.

Design/methodology/approach

The viscoelastic behavior of pipe wall is mathematically modeled by using the rheological model of Maxwell. The arbitrary Lagrangian–Eulerian (ALE) method is also used to simulate fluid–structure interaction. In this method, unlike the classical water hammer theory, the acoustic wave velocity is calculated during the numerical simulations and therefore it is not predetermined.

Findings

Investigating the velocity profiles and the shear stress diagrams for transient flow in elastic pipe showed that the strong effect of viscous forces on the near wall region in conjunction with the influence of inertial forces in the central region of the pipe leads to creation of reverse flow near the pipe wall. Comparing the numerical results obtained for elastic pipe with those of viscoelastic pipe revealed that during transient condition, the viscoelastic wall absorbs the energy of fluid and therefore pressure fluctuations of viscoelastic pipe are damped more quickly. Moreover, the 3D simulation of water hammer confirmed the plane wave hypothesis of water hammer.

Originality/value

The 3D Navier–Stokes equations are solved considering the viscoelasticity of the pipe and the ALE method using the software package of COMSOL Multiphysics.

Details

World Journal of Engineering, vol. 15 no. 2
Type: Research Article
ISSN: 1708-5284

Keywords

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Article
Publication date: 16 June 2023

Mohammad Ali Fallah, Mehrdad Agha Mohammad Ali Kermani, Alireza Moini and Javad Mashayekh

The present research is trying to construct the network of relationships between different department of an organization during the design and development of car engine. Analyzing…

264

Abstract

Purpose

The present research is trying to construct the network of relationships between different department of an organization during the design and development of car engine. Analyzing the structure of the network, finding the patterns of collaborations, and determining the important departments are the main purposes of the present research.

Design/methodology/approach

Improving relationships during a project life is an effective way to enhance employee performance in project-oriented organizations. This paper examines the collaborative relationships between internal project stakeholders through social network analysis (SNA) in a project for the design and development of car engine. In the first step of the research, the network of internal stakeholders was studied based on collaboration in the common activities performed by the resources. Then, the network of correspondences between internal stakeholders was studied. Finally, the two networks were integrated into a single network.

Findings

In the integrated network, the “fuel and combustion department” had the largest degree centrality (i.e. highest collaboration with others). The “integration department” was found to have the highest closeness centrality (i.e. more rapid access to other nodes). Furthermore, the “procurement department” had the highest betweenness centrality (i.e. the most strategic department). Our results revealed the potential capabilities of SNA method for the project management in the vehicle industry.

Originality/value

The obtained results of the present research show us the value of applying SNA methods and concepts to analyze the inter-organizational network of the Project Stakeholders relationship.

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Article
Publication date: 23 September 2022

Amir Amjad Mohammadi, Hadi Safaeipour, Mohammad Reza Chenaghlou, Alireza Behnejad and Roham Afghani Khoraskani

This paper aims at discovering the traditional techniques of Persian architecture for covering large-span spaces with a kind of ribbed vault titled “Karbandi”. This structure is…

118

Abstract

Purpose

This paper aims at discovering the traditional techniques of Persian architecture for covering large-span spaces with a kind of ribbed vault titled “Karbandi”. This structure is generated by intersecting several arches with a harmonic stellar geometry. Preliminary studies show that span factor affects the structural form of karbandi and large-span cases, despite similar architectural forms, have different structural systems and specific construction methods. The main focus of this paper is how karbandi has been designed and built on large-spans. To answer this question, the configuration and construction of a large-span karbandi in Tabriz Bazaar were recognized.

Design/methodology/approach

Data collection of the research was initially done in three parallel directions through the archival study of restoration documents, direct observation of the corpus of the vaultings and interviews with the master mason of the Haj-Mohammad-Qoli Timche restoration team. Then by cross-referencing the gathered data, the construction process of the karbandi was simulated in Rhino 6 and Grasshoppers software and its BIM-M models were created in three levels of development: LOD300, LOD350 and LOD400. In the next step, the preliminary BIM-M models of the karbandi were presented to the interviewed mason and revised and completed based on his comments.

Findings

Analyzing the BIM models by reverse engineering, resulted in (1) Discovering a unique self-supporting masonry construction method applied for the erection of karbandi vaulting on large-spans. (2) Finding the effect of scale factor on the architectural and structural form of the karbandi vault. (3) Discovering the connection types of the karbandi vault based on the construction details.

Originality/value

Despite the wide applications of karbandi vaults throughout history, very little information of their construction techniques is available. The techniques have mostly been experientially and orally passed down from masters to apprentices and rarely been documented. The quest to design and construct a karbandi vault is therefore like solving a puzzle whose most important guide is historical cases. Due to the geometric complexity of karbandi and its ability to cover large-span spaces, solving the puzzle can lead to achieving some technical ideas for masonry cross-ribbed vaulting. A great riddle of the karbandi vaults is how to design and build them on a large span.

Details

Engineering, Construction and Architectural Management, vol. 31 no. 1
Type: Research Article
ISSN: 0969-9988

Keywords

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