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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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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

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.

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

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.

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.

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.

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.

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

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.

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.

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.

Collaboration is significant but difficult for the development of youth organizations, this research aims to explore whether the online collaboration process is suitable for youth organizations' collaboration and improve their effectiveness and efficiency.

This research has applied a design approach using the collaboration engineering method, to design an online collaboration process for youth organizations to improve their effectiveness and efficiency. Using a self-developed group support systems (GSS) tool, the authors have tested the new collaboration process through an experiment among four youth organizations and conducted a survey afterwards.

The new process improves the collaboration effectiveness and efficiency. The research also identifies the detailed relationships among influencing factors in the online collaboration process.

There is little research in the context of computer mediated youth organization collaboration. This research designs an online collaboration process for the effective and efficient collaboration of youth organizations and has it tested among representative youth organizations, providing practical instructions for digital youth organization collaboration in the context of global pandemic.

The purpose of this study is to investigate whether research and development (R&D) activities reduce the performance damage caused by a critical situation, such as the COVID-19 pandemic, or not. Also, this study tries to explain whether the market in its reactions pays attention to companies' R&D activities or not during the COVID-19 critical situation.

The official announcement of the COVID-19 disease in Iran is considered the date of the event in this study. To consider the effect of R&D activities on the performance, three similar time periods before and after the coronavirus pandemic have been considered. Due to the widespread prevalence of coronavirus in Iran, this country has been selected to answer the research questions.

The results showed that the companies that have more R&D activities performed better than other companies during this period and were able to better manage this crisis. Furthermore, companies with more R&D activities suffered lower abnormal returns during coronavirus shocks than other companies.

Based on the research results, the issues that were discussed on the importance of R&D activities in the accounting literature is confirmed, and the results show the importance of R&D activities on the company's ability to overcome crises.

Based on the results of this research, it can be suggested that even in difficult and critical conditions, investment in R&D activities should not be stopped and decrease.

In the accounting literature, the long-term effect of R&D activities on the survival of companies has always been considered. In this study, the effect of R&D activities on market response and firm performance in a real shock is investigated, which is the innovation of this research.

The purpose of this paper is to present a new approximate analytical procedure to obtain dual solutions of nonlinear differential equations arising in mixed convection flow in a semi-infinite domain. This method, which is based on Padé-approximation and homotopy–Padé technique, is applied to a model of magnetohydrodynamic Falkner–Skan flow as well. These examples indicate that the method can be successfully applied to solve nonlinear differential equations arising in science and engineering.

Homotopy–Padé method.

The main focus of the paper is on the prediction of the multiplicity of the solutions, however we have calculated multiple (dual) solutions of the model problem namely, mixed convection heat transfer in a porous medium.

The authors conjecture here that the combination of traditional–Pade and Hankel–Pade generates a useful procedure to predict multiple solutions and to calculate prescribed parameter with acceptable accuracy as well. Validation of this conjecture for other further examples is a challenging research opportunity.

Dual solutions of nonlinear differential equations arising in mixed convection flow in a semi-infinite domain.

In this study, the authors are using two modified methods.