The results obtained from previous studies are not found to be sufficient for hydrostatic bearing design optimisation since thermodynamic effects are not considered. Therefore…
Abstract
Purpose
The results obtained from previous studies are not found to be sufficient for hydrostatic bearing design optimisation since thermodynamic effects are not considered. Therefore, this research is presented with considering parameter variations based on thermodynamic effects for more efficient optimisation of bearing parameters.
Design/methodology/approach
Single and multi‐criteria approaches were carried out to determine the hydrostatic journal bearing design parameters so that the total performance of the system is optimal.
Findings
It is seen that firstly, the results of single criteria approaches for minimum power, bearing coefficient and minimum temperature rise in circular hydrostatic axial journal bearings are not sufficient, secondly, there is a crucial need to consider multiple criteria optimisation cases and thirdly, thermodynamic effects must be taken into account for more efficient approach to compute the optimum values of bearing design parameters.
Research limitations/implications
Further research is required to develop a genetic algorithm‐based optimisation for bearing design problems considering thermodynamic effects and multiple criteria approaches to compare the results of present study.
Practical implications
Comparison of optimisation results of single and multi‐criteria approaches are given to show temperature variation effects on bearing performance.
Originality/value
Although, there are some works related to design and optimisation of hydrostatic bearings, most of them consider the single criteria optimisation and thermodynamic effects are not usually taken into account. Therefore, this research is different than others since the present approach is implemented with thermodynamic effects and also not limited to single criteria approach.
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The purpose of this paper is to evaluate and compare the protective, anticorrosion properties of silane- and polyrhodanine-based bilayer coatings pRh/IBTES and IBTES/pRh on an…
Abstract
Purpose
The purpose of this paper is to evaluate and compare the protective, anticorrosion properties of silane- and polyrhodanine-based bilayer coatings pRh/IBTES and IBTES/pRh on an X20Cr13 stainless steel substrate.
Design/methodology/approach
IBTES/pRh and pRh/IBTES have been coated using the dip-coating method and the cyclic voltammetry technique. The electrochemical measurements have been used to assess the anticorrosion properties of the resulting bilayer coatings. Morphological and chemical characterizations have been performed using scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS).
Findings
The results clearly show that the combination of both the deposits of polyrhodanine and silane yields a more protective structure that affords better protection against corrosion with time. The best barrier properties are achieved by the substrates coated with polyrhodanine film upon which silane is subsequently adsorbed – the pRh/IBTES bilayer coating.
Originality/value
The paper reveals that the procedure of modification of silane films with polyrhodanine had a marked effect on the anti-corrosive performance of the obtained two types of bilayers coatings (pRh/IBTES, IBTES/pRh) applied on a stainless steel surface. The coating where polyrhodanine was first electrodeposited on the steel surface and then the silane layer adsorbed (pRh/IBTES) achieved the best protective properties.
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Cheng Boon Liat, S.R. Nikhashemi and Michael M. Dent
Having Middle Eastern tourism industry as the context, this study aims to examine the impact of the four main dimensions within service innovation (i.e. product, process…
Abstract
Purpose
Having Middle Eastern tourism industry as the context, this study aims to examine the impact of the four main dimensions within service innovation (i.e. product, process, organizational and marketing innovations) on tourist satisfaction; subsequently, towards the development of destination loyalty. Realized that religiosity prevails as an important social force that shapes individual behaviours, this study, hence, placed further assessment upon its moderating role, specifically in the relationships between tourist satisfaction and destination loyalty.
Design/methodology/approach
With adopting the approach of self-structured questionnaire, 214 usable responses had been collected for this study. Obtained data was then analyzed by conducting exploratory factor analysis, confirmatory factor analysis and multiple linear regression analysis through the usage of structural equation modelling.
Findings
Analysis of obtained data has revealed all the investigated dimensions within service innovation as active predictors to tourist satisfaction, with the exception of product innovation, while having marketing innovation being of highest significance. In turn, tourist satisfaction is found to greatly influence the formation of destination loyalty. Findings then provide notable indication on religiosity as a moderating factor to the proposed relationships within the investigated framework, between service innovation and tourist satisfaction, as well as tourist satisfaction and destination loyalty.
Originality/value
This study, thus, revealed the level of religiosity, particularly from the standpoint of Islamic perspectives, in playing a critical role towards predicting capability of service innovation on tourist satisfaction, and further, destination loyalty. Contributions hereby lie on theoretical and pragmatic insights concerning aspects of service and Islamic marketing within today’s tourism front.
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E. Solmaz, F.C. Babalık and F. Öztürk
In this paper, computer‐aided design optimization approach for hydrostatic bearings is presented. The optimization problem is formulated in multicriteria strategy. The power loss…
Abstract
In this paper, computer‐aided design optimization approach for hydrostatic bearings is presented. The optimization problem is formulated in multicriteria strategy. The power loss and the temperature rise of oil are considered as performance measures for optimal hydrostatic bearing design. Optimization results indicate the effectiveness of the proposed combined approach which has advantages over the single criteria optimization. Sample results are presented to verify the proposed approach.
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Waheed Ur Rehman, Xinhua Wang, Yingchun Chen, Xiaogao Yang, Zia Ullah, Yiqi Cheng and Marya Kanwal
The purpose of this paper is to improve static/dynamic characteristics of active-controlled hydrostatic journal bearing by using fractional order control techniques and optimizing…
Abstract
Purpose
The purpose of this paper is to improve static/dynamic characteristics of active-controlled hydrostatic journal bearing by using fractional order control techniques and optimizing algorithms.
Design/methodology/approach
Active lubrication has ability to overcome the unpredictable harsh environmental conditions which often lead to failure of capillary controlled traditional hydrostatic journal bearing. The research develops a mathematical model for a servo feedback-controlled hydrostatic journal bearing and dynamics of model is analyzed with different control techniques. The fractional-order PID control system is tuned by using particle swarm optimization and Nelder mead optimization techniques with the help of using multi-objective performance criteria.
Findings
The results of the current research are compared with previously published theoretical and experimental results. The proposed servo-controlled active bearing system is studied under a number of different dynamic situations and constraints of variable spindle speed, external load, temperature changes (viscosity) and variable bearing clearance (oil film thickness). The simulation results show that the proposed system has better performance in terms of controllability, faster response, stability, high stiffness and strong resistance.
Originality/value
This paper develops an accurate mathematical model for servo-controlled hydrostatic bearing with fractional order controller. The results are in excellent agreement with previously published literature.
Peer review
The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-07-2020-0272
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Evrim Baran Aydın, Eyüp Başaran, Sevgi Ateş and Reşit Çakmak
The aim of this study was to investigate the activity of 4-((4-((2-hydroxyethyl)(methyl)amino)benzylidene) amino)-1,5-dimethyl-2-phenyl-1,2-dihydro-3H-pyrazol-3-one (HEMAP), a…
Abstract
Purpose
The aim of this study was to investigate the activity of 4-((4-((2-hydroxyethyl)(methyl)amino)benzylidene) amino)-1,5-dimethyl-2-phenyl-1,2-dihydro-3H-pyrazol-3-one (HEMAP), a Schiff base synthesized and characterized for the first time, to the authors’ knowledge, as a novel inhibitor against corrosion of mild steel (MS) in hydrochloric acid solution.
Design/methodology/approach
HEMAP was characterized by some spectroscopic methods including High-Resolution Mass Spectrometry (HRMS), Proton Nuclear Magnetic Resonance (1H NMR), Carbon-13 (C13) nuclear magnetic resonance (13C NMR) and Fourier Transform Infrared Spectroscopy (FT-IR). Then, the inhibition efficiency of HEMAP on MS in a hydrochloric acid solution was investigated by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). To explain the inhibition mechanism, the surface charge, adsorption isotherms and thermodynamic parameters of MS in the inhibitor solution were studied.
Findings
EIS tests displayed that the highest inhibition efficiency was calculated approximately as 99.5% for 5 × 10−2 M HEMAP in 1 M HCl solution. The adsorption of HEMAP on the MS surface was found to be compatible with the Langmuir model isotherm. The thermodynamic parameter results showed that the standard free energy of adsorption of HEMAP on the MS surface was found to be more chemical than physical.
Originality/value
This study is important in terms of demonstrating the performance of the first synthesized HEMAP molecule as an inhibitor against the corrosion of MS in acidic media. EIS tests displayed that the highest inhibition efficiency was calculated approximately as 99.5% for 5 × 10−2 M HEMAP in 1 M HCl solution.
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Gülfer Akça, Aslihan Sanri and Unal Akca
This study aims to evaluate the health literacy level of the parents of children diagnosed with Down syndrome (DS) within one institution in Turkey.
Abstract
Purpose
This study aims to evaluate the health literacy level of the parents of children diagnosed with Down syndrome (DS) within one institution in Turkey.
Design/methodology/approach
A cross-sectional survey measuring demographics, information of the child and the parent and health literacy was administered to participants. The health literacy levels in the study were measured with the European Health Literacy Scale (EHLS), which consists of 47 questions.
Findings
Of the 65 participants who completed the questionnaire, 56.9% were mothers, 68.1% were diagnosed in the neonatal outpatient clinic examination after birth, and 58.5% stayed in the neonatal intensive care unit after birth. The mean score of the IHLS scale was 25.06 ± 6.59. Of the parents, 63.1% were found to be inadequate, 18.5% problematic-limited, and 18.5% adequate health literate. Any parent with excellent health literacy level was identified. High education level (p < 0.001), high income level (p < 0.001), living in the city center (p < 0.05), planned pregnancy (p < 0.05) and being a health worker (p < 0.001) were found to be statistically significant with a high EHSL score.
Research limitations/implications
The presence of Down syndrome (DS) in a child also necessitates ongoing monitoring for a range of conditions, including eye diseases and heart disease. Some surgical procedures, such as heart or gastrointestinal surgeries, may also be required. Additionally, the child may require the administration of various medications. Finally, due to the potential lifelong need for assistance, the child may require the support of an adult throughout their lifetime. This is because of the child's inability to live independently due to their mental state. Therefore, parent education is the most important issue in the follow-up of the disease.
Practical implications
To the best of the authors’ knowledge, this is the first study to determine that parents of children diagnosed with DS have very limited knowledge of the disease and health literacy. Explanation of current diseases, treatments and training of parents should also be included in genetic counseling.
Social implications
DS is a chromosomal disease that requires multidisciplinary care. Parents have to know the course of the disease and its complications.
Originality/value
The findings of this study indicate that parents of children with Down syndrome exhibit a profound lack of knowledge regarding the nature of their child's condition and the available healthcare options. It is therefore imperative that genetic counseling incorporates an explanation of the diagnosed diseases, treatments, and educational resources for parents.
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To characterise the optimal design parameters which are useful in hydrostatic radial journal bearings design.
Abstract
Purpose
To characterise the optimal design parameters which are useful in hydrostatic radial journal bearings design.
Design/methodology/approach
A computer program is developed. With this program, designers can determine and select all design parameters of the hydrostatic radial journal bearings. Design parameters are searched with an optimisation algorithm which is used as a multi‐criteria optimisation approach.
Findings
With this approach, the designer can use the time effectively. This approach is faster and more precise than other approaches in the literature.
Research limitations/implications
This approach is valid only for a specific type of hydrostatic journal bearings and within limits of shaft velocity. This approach should be improved.
Practical implications
This approach can especially be used for the hydrostatic journal bearings which are used for shafts‐turned middle velocities.
Originality/value
This paper fulfils the requests of the journal bearing designers exactly and quickly. In this research area, there is no another program.
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Sang Xiong, Jia Si, Jianlin Sun, Hao Wu, Hongchen Dong and Chao Zhang
Corrosion inhibitors for copper immersed in emulsion were investigated by experiments and theoretical calculations, and this study aims to propose a new inhibition mechanism of…
Abstract
Purpose
Corrosion inhibitors for copper immersed in emulsion were investigated by experiments and theoretical calculations, and this study aims to propose a new inhibition mechanism of the inhibitors having protective effects for copper corrosion.
Design/methodology/approach
Adsorption behavior of penta-heterocycles (thiophene, 1,2,5-oxadiazole, furan, 2 H-1,2,3-triazole, pyrrole and 1,2,5-thiadiazole) as corrosion inhibitors for copper immersed in oil-in-water (O/W) emulsions was investigated by weight loss, electrochemical tests, morphological characterization and theoretical calculations.
Findings
The orders of inhibition effect are furan < pyrrole < thiophene < 1,2,5-oxadiazole < 2H-1,2,3-triazole < 1,2,5-thiadiazole, and 1,2,5-thiadiazole at 0.5 mM has the best inhibition effect for copper immersed in emulsion. The results of scanning probe microscope, scanning electron microscope and electrochemical test show that a protective barrier can be formed on the surface of copper substrate with six corrosion inhibitors, thus effectively inhibiting the corrosion of copper mainly through chemisorption and following Langmuir’s adsorption isotherm.
Originality/value
Quantum chemical and molecular dynamic simulations demonstrate that all these compounds attached to Cu matrix with a flat-adsorption mode to prevent the emulsion corrode copper. Adsorbed inhibitors act as a barrier at Cu matrix to block corrosion and improve hydrophobicity.
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Marzia Hoque Tania, M. Shamim Kaiser, Kamal Abu-Hassan and M. A. Hossain
The gradual increase in geriatric issues and global imbalance of the ratio between patients and healthcare professionals have created a demand for intelligent systems with the…
Abstract
Purpose
The gradual increase in geriatric issues and global imbalance of the ratio between patients and healthcare professionals have created a demand for intelligent systems with the least error-prone diagnosis results to be used by less medically trained persons and save clinical time. This paper aims at investigating the development of image-based colourimetric analysis. The purpose of recognising such tests is to support wider users to begin a colourimetric test to be used at homecare settings, telepathology and so on.
Design/methodology/approach
The concept of an automatic colourimetric assay detection is delivered by utilising two cases. Training deep learning (DL) models on thousands of images of these tests using transfer learning, this paper (1) classifies the type of the assay and (2) classifies the colourimetric results.
Findings
This paper demonstrated that the assay type can be recognised using DL techniques with 100% accuracy within a fraction of a second. Some of the advantages of the pre-trained model over the calibration-based approach are robustness, readiness and suitability to deploy for similar applications within a shorter period of time.
Originality/value
To the best of the authors’ knowledge, this is the first attempt to provide colourimetric assay type classification (CATC) using DL. Humans are capable to learn thousands of visual classifications in their life. Object recognition may be a trivial task for humans, due to photometric and geometric variabilities along with the high degree of intra-class variabilities, it can be a challenging task for machines. However, transforming visual knowledge into machines, as proposed, can support non-experts to better manage their health and reduce some of the burdens on experts.