Search results

1 – 10 of 64
Article
Publication date: 29 June 2012

R. Mehdipour, C. Aghanajafi and A. Ashrafizadeh

The purpose of this paper is to model radiation ovens and to propose a method capable of designing this kind of oven for the paint curing application. Providing a uniform cure…

Abstract

Purpose

The purpose of this paper is to model radiation ovens and to propose a method capable of designing this kind of oven for the paint curing application. Providing a uniform cure condition on the body, especially bodies of complicated geometries, needs accurately‐designed ovens. An algorithm with high speed and high convergence capability is the most serious requirement for designing ovens of this kind.

Design/methodology/approach

In this paper, the state of the art in dynamic optimisation of radiation paint cure ovens is reviewed and a novel objective function, based on paint cure window, is proposed to be applied for designing radiation ovens. It has been shown that the proper definition of the objective function in such problems makes the mathematical model more robust and hence facilitates the convergence of the design iterations.

Findings

The computational results provide some information regarding the design space topology and show that the proposed objective function speeds up the convergence of the design procedure by an order of magnitude as compared to the currently used industrial‐standard objective function.

Practical implications

Determination of curing condition is an important requirement for designing a new oven or changing the working condition of an existing oven. In this research, a practical method is proposed for improving design procedure of cure ovens to make the method both time and cost efficient. The method is specifically implemented on paint cure ovens.

Originality/value

The quality of cured paint is usually a prominent issue that directly takes influence from the curing condition of ovens. For the complex geometries of curing body in commonly designed ovens, some areas are not properly cured or may be burnt. This issue is a significant defect in coating industry. Designing ovens with the proposed method in this paper guaranties the provided curing condition by the oven and therefore the curing quality.

Details

Pigment & Resin Technology, vol. 41 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 15 July 2021

Yang Liu, Qingwei Gong, Yongning Bian and Qinghui Suo

Hydrodynamic forces and efficiency of bare propeller and ducted propellers with a wide range of advance ratio (J) and attack angle (θ) are examined. The thrust and torque…

Abstract

Purpose

Hydrodynamic forces and efficiency of bare propeller and ducted propellers with a wide range of advance ratio (J) and attack angle (θ) are examined. The thrust and torque coefficients and the efficiency are presented and discussed in detail. The present results give a reliable guidance to the improvement of the hydrodynamic characteristics of ducted propellers.

Design/methodology/approach

The effect of a duct on the hydrodynamic performance of the KP458 propeller is numerically investigated in this study. Finite volume method (FVM)-based simulations are performed for a wide range of advance ratio J (0 ≤ J ≤ 0.75) and attack angle θ of the duct (15° ≤ θ ≤ 45°). A cubic computational domain is employed in this study, and the moving reference frame (MRF) approach is adopted to handle the rotation of the propeller. Turbulence is accounted for with the RNG k-ε model. The present numerical results are first compared against available experimental data and a good agreement is achieved.

Findings

The simulation results demonstrate that the hydrodynamic forces and efficiency increases and decreases with J, respectively, at the same attack angle. In addition, it is demonstrated that the hydrodynamic forces and efficiency are both improved due to the presence of the duct, which eventually leads a better hydrodynamic performance at high advance ratios. It is further revealed that as the attack angle increases, the pressure difference between the suction- and pressure-surfaces of the propeller is also augmented, which results in a larger thrust. The wake field is more uniform at θ = 30°, suggesting that a higher efficiency can be obtained.

Originality/value

The present study aims to investigate the effect of a duct on the KP458 propeller subjected to uniform inbound flow. The relationship between the uniform incoming flow and the attack angle of the duct is mainly focused, and the design of the ducted propellers for any ship hull can be improved according to this relationship.

Details

Engineering Computations, vol. 39 no. 2
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 15 August 2024

Sameer Dubey, Pradeep Vishwakarma, TVS Ramarao, Satish Kumar Dubey, Sanket Goel and Arshad Javed

This study aims to introduce a vision-based model to generate droplets with auto-tuned parameters. The model can auto-adjust the inherent uncertainties and errors involved with…

Abstract

Purpose

This study aims to introduce a vision-based model to generate droplets with auto-tuned parameters. The model can auto-adjust the inherent uncertainties and errors involved with the fabrication and operating parameters in microfluidic platform, attaining precise size and frequency of droplet generation.

Design/methodology/approach

The photolithography method is utilized to prepare the microfluidic devices used in this study, and various experiments are conducted at various flow-rate and viscosity ratios. Data for droplet shape is collected to train the artificial intelligence (AI) models.

Findings

Growth phase of droplets demonstrated a unique spring back effect in droplet size. The fully developed droplet sizes in the microchannel were modeled using least absolute shrinkage and selection operators (LASSO) regression model, Gaussian support vector machine (SVM), long short term memory (LSTM) and deep neural network models. Mean absolute percentage error (MAPE) of 0.05 and R2 = 0.93 were obtained with a deep neural network model on untrained flow data. The shape parameters of the droplets are affected by several uncontrolled parameters. These parameters are instinctively captured in the model.

Originality/value

Experimental data set is generated for varying viscosity values and flow rates. The variation of flow rate of continuous phase is observed here instead of dispersed phase. An automated computation routine is developed to read the droplet shape parameters considering the transient growth phase of droplets. The droplet size data is used to build and compare various AI models for predicting droplet sizes. A predictive model is developed, which is ready for automated closed loop control of the droplet generation.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 34 no. 8
Type: Research Article
ISSN: 0961-5539

Keywords

Open Access
Article
Publication date: 21 June 2024

Mohammad Reza Shokouhi, Mohammad Torabi, Rasoul Salimi and Parisa Hajiloo

Emergency Medical Services (EMS) providers are often faced with a range of ethical dilemmas in their line of work that require moral courage to make a quick and ethical decision…

Abstract

Purpose

Emergency Medical Services (EMS) providers are often faced with a range of ethical dilemmas in their line of work that require moral courage to make a quick and ethical decision. The purpose of this study is to investigate the level of professional moral courage (PMC) in EMS providers and its relationship with their demographic characteristics.

Design/methodology/approach

In 2022, a cross-sectional descriptive study was conducted on 175 EMS providers at the Hamadan Emergency Medical Center. The study utilized an available sampling method. Data was collected using a demographic information form and Sekerka's moral courage questionnaire, which was distributed electronically. The collected data was analyzed using SPSS 26 software with descriptive and analytic tests.

Findings

According to the findings, the average age of the participants was 34.57 ± 3.46 years. The majority of participants were married (50.3%), had work experience ranging from 8 to 14 years (49.7%), and held a degree in emergency medicine (52.6%). The participants displayed a high level of PMC, with an average score of 62.5 ± 8.14. Notably, age, work experience, educational level, and employment status were all found to have a significant relationship with moral courage (p < 0.05) among the demographic characteristics.

Research limitations/implications

The study has a limitation in terms of the sampling method employed, which may impact the generalizability of the results. Another limitation, by a narrow margin, is that the sample size is smaller than what was estimated. Furthermore, using various measurement tools to assess PMC might lead to varying outcomes. Consequently, it is recommended that future research incorporates random sampling and devises a dedicated psychometric instrument to assess the PMC of EMS providers.

Originality/value

The results revealed a positive correlation between work experience and PMC among providers. This can be attributed to the challenges and outcomes they have encountered throughout their careers. Moreover, EMS providers with higher educational qualifications and job stability demonstrated higher levels of moral courage.

Details

International Journal of Emergency Services, vol. 13 no. 2
Type: Research Article
ISSN: 2047-0894

Keywords

Article
Publication date: 23 November 2023

Sayed Arash Hosseini Sabzevari, Haleh Mehdipour and Fereshteh Aslani

Golestan province in the northern part of Iran has been affected by devastating floods. There has been a significant change in the pattern of rainfall in Golestan province based…

Abstract

Purpose

Golestan province in the northern part of Iran has been affected by devastating floods. There has been a significant change in the pattern of rainfall in Golestan province based on an analysis of the seven heaviest rainfall events in recent decades. Climate change appears to be a significant contributing factor to destructive floods. Thus, this paper aims to assess the susceptibility of this area to flash floods in case of heavy downpours.

Design/methodology/approach

This paper uses a variety of computational approaches. Following the collection of data, spatial analyses have been conducted and validated. The layers of information are then weighted, and a final risk map is created. Fuzzy analytical hierarchy process, geographic information system and frequency ratio have been used for data analysis. In the final step, a flood risk map is prepared and discussed.

Findings

Due to the complex interaction between thermal fluctuations and precipitation, the situation in the area is further complicated by climate change and the variations in its patterns and intensities. According to the study results, coastal areas of the Caspian Sea, the Gorganrood Basin and the southern regions of the province are predicted to experience flash floods in the future. The research criteria are generalizable and can be used for decision-making in areas exposed to flash flood risk.

Originality/value

The unique feature of this paper is that it evaluates flash flood risks and predicts flood-prone areas in the northern part of Iran. Furthermore, some interventions (e.g. remapping land use and urban zoning) are provided based on the socioeconomic characteristics of the region to reduce flood risk. Based on the generated risk map, a practical suggestion would be to install and operate an integrated rapid flood warning system in high-risk zones.

Details

International Journal of Disaster Resilience in the Built Environment, vol. 15 no. 3
Type: Research Article
ISSN: 1759-5908

Keywords

Article
Publication date: 3 January 2017

Bahram Ramezanzadeh, Milad Mehdipour, S.Y. Arman and M. Ramezanzadeh

This study attempts to investigate corrosion inhibition properties of 1H-benzimidazole (B) and 1H-benzotriazole (BTA) on aluminum in 0.25 M HCl solution at different…

Abstract

Purpose

This study attempts to investigate corrosion inhibition properties of 1H-benzimidazole (B) and 1H-benzotriazole (BTA) on aluminum in 0.25 M HCl solution at different concentrations.

Design/methodology/approach

To this end, electrochemical techniques including electrochemical noise (EN), electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization were used.

Findings

Results showed a greater corrosion inhibition efficiency of BTA than B on aluminum in HCl solution. BTA showed greater tendency to adsorption on the metal surface than B because of the inclusion of three nitrogen atoms.

Originality/value

The novelty of this work is comparing EN data with EIS and potentiodynamic polarization parameters.

Details

Anti-Corrosion Methods and Materials, vol. 64 no. 1
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 29 December 2023

Jason Von Meding, Carla Brisotto, Haleh Mehdipour and Colin Lasch

This paper will challenge normative disaster studies and practice by arguing that thriving communities require the pursuit of imperfection and solidarity. The authors use Lewis…

Abstract

Purpose

This paper will challenge normative disaster studies and practice by arguing that thriving communities require the pursuit of imperfection and solidarity. The authors use Lewis Carroll’s Looking-Glass World as a lens to critique both how disasters are understood, and how disaster researchers and practitioners operate, within a climate-change affected world where cultural, political and historical constructs are constantly shifting.

Design/methodology/approach

The paper will undertake an analysis of both disasters and disaster studies, using this unique (and satirical) critical lens, looking at the unfolding of systemic mistakes, oppressions and mal-development that are revealed in contemporary disasters, that were once the critiques of Lewis Carroll’s Victorian-era England. It shows how disaster “resilience-building” can actually be a mechanism for continuing the status quo, and how persistent colonizing institutions and systems can be in reproducing themselves.

Findings

The authors argue the liberation of disaster studies as a process of challenging the doctrines and paradigms that have been created and given meaning by those in power – particularly white, Western/Northern/Eurocentric, male power. They suggest how researchers and practitioners might view disasters – and their own praxis – Through the Looking Glass in an effort to better understand the power, domination and violence of the status quo, but also as a means of creating a vision for something better, arguing that liberation is possible through community-led action grounded in love, solidarity, difference and interconnection.

Originality/value

The paper uses a novel conceptual lens as a way to challenge researchers and practitioners to avoid the utopic trap that wishes to achieve homogenized perfection and instead find an “imperfect” and complex adaptation that moves toward justice. Considering this idea through satire and literary criticism will lend support to empirical research that makes a similar case using data.

Details

Disaster Prevention and Management: An International Journal, vol. 33 no. 3
Type: Research Article
ISSN: 0965-3562

Keywords

Book part
Publication date: 6 September 2019

Abstract

Details

Experiencing Persian Heritage
Type: Book
ISBN: 978-1-78754-813-8

Open Access
Article
Publication date: 20 November 2023

David D. Walker, Su Kyung (Irene) Kim, Danielle D. van Jaarsveld, Simon Lloyd D. Restubog, Mauricio Marrone, Constantin Lagios and Arman Michael Mehdipour

The authors systematically review empirical dyadic service encounter research published in top-tier journals between 1972 and 2022.

1393

Abstract

Purpose

The authors systematically review empirical dyadic service encounter research published in top-tier journals between 1972 and 2022.

Design/methodology/approach

The authors employed bibliometric techniques, co-citation analysis and bibliographic coupling analysis to map schools of thought and research frontiers within the dyadic service encounter literature. In total, the authors analyzed 155 articles. To ensure inclusion of high-quality research, the authors screened articles from 139 journals with “4” or “4*” ratings on the 2021 Chartered Association of Business Schools (ABS) journal list, in addition to articles published in three service sector-specific journals: Journal of Service Management, Journal of Services Marketing and Journal of Service Theory and Practice.

Findings

The authors' co-citation analysis identified four distinct clusters within the dyadic service encounter literature: (1) shaping and explaining service encounters; (2) emotions in service work; (3) modeling, manipulating and measuring encounter service quality and (4) emotional labor and regulation in dyadic service encounters. Furthermore, the authors' bibliographic coupling analysis generated three research clusters: (1) service encounter characteristics; (2) emotions and emotional labor and (3) service encounter interaction content.

Originality/value

The authors' comprehensive review synthesizes knowledge, summarizing similarities among research clusters within the service encounter realm. Noteworthy are research clusters that clarify the emotion-based underpinnings and reciprocal nature of behaviors and emotions within dyadic encounters. By conducting complementary bibliometric analyses, the authors trace the evolution of the service encounter literature, providing an overview of the present state of dyadic service encounter research. These analyses offer valuable insights into the current landscape of the field, identifying future dyadic service encounter research opportunities.

Details

Journal of Service Management, vol. 34 no. 5
Type: Research Article
ISSN: 1757-5818

Keywords

Article
Publication date: 23 August 2024

Haleh Mehdipour, Marjorie Prokosch, Darien Williams, Abdul-Hai Thomas, Brian Seymour, Jacqueline Conley and Jason von Meding

The paper explores the implementation and process of a Participatory Action Research (PAR) project in Jacksonville, Florida. Using PAR principles, we sought to disrupt traditional…

79

Abstract

Purpose

The paper explores the implementation and process of a Participatory Action Research (PAR) project in Jacksonville, Florida. Using PAR principles, we sought to disrupt traditional dynamics in research, co-generating knowledge with the community. We aimed to elevate disenfranchised voices and foster effective solutions for neighborhood revitalization and resilience, which are designed and led by the community. In this paper we explore researcher positionality, examining how engagement with the community context profoundly influences researchers' perspectives and roles, thereby shaping the study trajectory.

Design/methodology/approach

We use reflexive and thematic approaches to analyze researcher positionalities and dynamics with the community. Researchers' reflections were scrutinized with a focus on their backgrounds, adaptability to community pace of work, lessons learned and evolving perspectives on community-centered research. We present a comprehensive discussion of emerging themes and emphasize the transformative nature of PAR and the significance of the researcher pursuing a relationship of belonging within the community.

Findings

The study uncovered key themes clarifying the transformations experienced by researchers engaged in PAR. We underwent a significant shift from a predetermined, structured PAR model to a more organic, community-driven model. This shift is illustrated under key themes in the paper: being vulnerable, valuing relationships, transforming the sense of self and solidarity, focusing on the process and recognizing and valuing community-derived knowledge. We write about the metamorphosis of researchers' roles from passive observers to active and empathic participants and about the implications for our methodological approach. As a result of this adaptation, the research process was enhanced and a symbiotic learning environment was created between the researchers and the community.

Originality/value

This paper distinguishes itself through its community-centric approach, diverging from traditional research paradigms. It explores how PAR-based community engagement can have a positive impact on those who are involved in PAR themselves, contributing to a better understanding of reciprocal dynamics in community-based research. We hope that our process of reflection can help other disaster researchers to ask better questions of themselves when engaging with communities and be open to following the lead and the pace of the community.

Details

Disaster Prevention and Management: An International Journal, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0965-3562

Keywords

1 – 10 of 64