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Article
Publication date: 1 September 1988

S.A. Fam, O.F. Moustafa, T.M. Ezzat and A.M. Motawie

A dewaxed and dearomatized petroleum fraction having a boiling range 180–250°C was oxidised by air at 140°C. under atmospheric pressure using cobalt or manganese naphthenate as…

500

Abstract

A dewaxed and dearomatized petroleum fraction having a boiling range 180–250°C was oxidised by air at 140°C. under atmospheric pressure using cobalt or manganese naphthenate as catalyst. The oxynaphthenic acids were isolated from the oxidation product, purified and then neutralised to sodium salts.

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Pigment & Resin Technology, vol. 17 no. 9
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 1 December 2008

John D. McLellan and Essam Moustafa

This article uses a survey of Certified Management Accountants (CMA) in the six Arab Gulf Cooperation Council (GCC) countries to examine the importance that CMAs place on a number…

625

Abstract

This article uses a survey of Certified Management Accountants (CMA) in the six Arab Gulf Cooperation Council (GCC) countries to examine the importance that CMAs place on a number of management accounting practices for the efficient operation of their business and to determine the degree of adoption of that management accounting practice by their organization. The findings indicate a large discrepancy between what accountants consider effective management accounting tools and the use of those tools by their companies’ senior management team. Evidence suggests that companies in the GCC rely on the traditional management accounting practices rather than the more recently developed tools. In addition, the management accountants of GCC companies feel that it would be more important for their businesses to emphasis a range of non‐financial tools as well as to adopt a more strategic management focus using tools.

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Journal of Economic and Administrative Sciences, vol. 24 no. 2
Type: Research Article
ISSN: 2054-6238

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Article
Publication date: 1 January 1991

M. Moustafa, I.A. Sabbah, S.I. Darwish and F. Abd El‐Hai

Rosin‐modified polyesteramide resins are prepared covering a wide range of oil lengths by partial replacement of hydroxy ethyl fatty acid amides employed in resin formulations by…

22

Abstract

Rosin‐modified polyesteramide resins are prepared covering a wide range of oil lengths by partial replacement of hydroxy ethyl fatty acid amides employed in resin formulations by rosin‐diethanolamine derivative without affecting the resin constants. This is followed by a study of the optimum amount of modifier which improve the resins performance and durability without affecting the other properties. Optimum modifier concentration and durability characteristics are then determined.

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Pigment & Resin Technology, vol. 20 no. 1
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 1 April 1989

A.Z. Gomaa, M.M. Metwally, M. Moustafa and M.A. Abd El‐Ghaffar

Insecticides are chemicals that are used to control damage or annoyance from insects. Generally, control is achieved by poisoning the insects by oral ingestion of stomach poisons…

33

Abstract

Insecticides are chemicals that are used to control damage or annoyance from insects. Generally, control is achieved by poisoning the insects by oral ingestion of stomach poisons, by contact poisons that penetrate through the cuticle, or by fumigants that penetrate through the respiratory system. Pojurowsky Leon has made wall paper washproof and contact‐insecticidal coating compositions by addition of 1–12% insecticide solutions in polar organic solvents in 15–45% amounts by usual vinyl‐acrylic or oil type emulsion lacquers. Coating dye compositions dispersible, in water and containing (MeO)2P(O)CH(OH)CC13 with lasting insecticide effect were prepared by Bozzay Jazsel, et al. In 1986, Lee, et al, have performed aqueous emulsions of insecticidal activity, containing hydrophilic silicone organic copolymer elastomer. Recently Moustafa, M., et al prepared and evaluated various coating compositions for their insecticidal activity. The binders used are chlorinated rubber, polyurethane and alkyd resins. Three kinds of insecticides with trade names sumicidin, sumithion and cyanox were studied. Cockroaches were the target insect. They showed that compositions based on alkyd or chlorinated rubber and containing 4% cyanox or sumithion as insecticide showed promising results as insecticidal and insect repellent coatings.

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Pigment & Resin Technology, vol. 18 no. 4
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 16 November 2021

Medhat Abd el Azem El Sayed Rostum, Hassan Mohamed Mahmoud Moustafa, Ibrahim El Sayed Ziedan and Amr Ahmed Zamel

The current challenge for forecasting smart meters electricity consumption lies in the uncertainty and volatility of load profiles. Moreover, forecasting the electricity…

149

Abstract

Purpose

The current challenge for forecasting smart meters electricity consumption lies in the uncertainty and volatility of load profiles. Moreover, forecasting the electricity consumption for all the meters requires an enormous amount of time. Most papers tend to avoid such complexity by forecasting the electricity consumption at an aggregated level. This paper aims to forecast the electricity consumption for all smart meters at an individual level. This paper, for the first time, takes into account the computational time for training and forecasting the electricity consumption of all the meters.

Design/methodology/approach

A novel hybrid autoregressive-statistical equations idea model with the help of clustering and whale optimization algorithm (ARSEI-WOA) is proposed in this paper to forecast the electricity consumption of all the meters with best performance in terms of computational time and prediction accuracy.

Findings

The proposed model was tested using realistic Irish smart meters energy data and its performance was compared with nine regression methods including: autoregressive integrated moving average, partial least squares regression, conditional inference tree, M5 rule-based model, k-nearest neighbor, multilayer perceptron, RandomForest, RPART and support vector regression. Results have proved that ARSEI-WOA is an efficient model that is able to achieve an accurate prediction with low computational time.

Originality/value

This paper presents a new hybrid ARSEI model to perform smart meters load forecasting at an individual level instead of an aggregated one. With the help of clustering technique, similar meters are grouped into a few clusters from which reduce the computational time of the training and forecasting process. In addition, WOA improves the prediction accuracy of each meter by finding an optimal factor between the average electricity consumption values of each cluster and the electricity consumption values for each one of its meters.

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COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 41 no. 1
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 29 October 2024

Saeed Reza Mohandes, Khalid Kaddoura, Atul Kumar Singh, Moustafa Y. Elsayed, Saeed Banihashemi, Maxwell Fordjour Antwi-Afari, Timothy O. Olawumi and Tarek Zayed

This study underscores the critical importance of well-functioning sewer systems in achieving smart and sustainable urban drainage within cities. It specifically targets the…

67

Abstract

Purpose

This study underscores the critical importance of well-functioning sewer systems in achieving smart and sustainable urban drainage within cities. It specifically targets the pressing issue of sewer overflows (SO), widely recognized for their detrimental impact on the environment and public health. The primary purpose of this research is to bridge significant research gaps by investigating the root causes of SO incidents and comprehending their broader ecological consequences.

Design/methodology/approach

To fill research gaps, the study introduces the Multi-Phase Causal Inference Fuzzy-Based Framework (MCIF). MCIF integrates the fuzzy Delphi technique, fuzzy DEMATEL method, fuzzy TOPSIS technique and expert interviews. Drawing on expertise from developed countries, MCIF systematically identifies and prioritizes SO causes, explores causal interrelationships, prioritizes environmental impacts and compiles mitigation strategies.

Findings

The study's findings are multifaceted and substantially contribute to addressing SO challenges. Utilizing the MCIF, the research effectively identifies and prioritizes causal factors behind SO incidents, highlighting their relative significance. Additionally, it unravels intricate causal relationships among key factors such as blockages, flow velocity, infiltration and inflow, under-designed pipe diameter and pipe deformation, holes or collapse, providing a profound insight into the intricate web of influences leading to SO.

Originality/value

This study introduces originality by presenting the innovative MCIF tailored for SO mitigation. The combination of fuzzy techniques, expert input and holistic analysis enriches the existing knowledge. These findings pave the way for informed decision-making and proactive measures to achieve sustainable urban drainage systems.

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Smart and Sustainable Built Environment, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2046-6099

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Article
Publication date: 11 October 2021

Moustafa Abdelmotaleb, Nacef Mouri and Sudhir K. Saha

The purpose of this study is to examine the relationship between leader-signaled knowledge-hiding behavior (LSKH) and employee organizational identification (OI) with…

840

Abstract

Purpose

The purpose of this study is to examine the relationship between leader-signaled knowledge-hiding behavior (LSKH) and employee organizational identification (OI) with self-interest climate perceptions (SIC) as a mediator. This study also takes into consideration the impact of individual differences (i.e. employee trait of agreeableness) in shaping these relationships.

Design/methodology/approach

Two-wave data were collected from a sample of employees working in service industry companies in Egypt (N = 305). The mediation model (model 4) and the moderated mediation model (model 14) were tested using the statistical package for the social sciences PROCESS macro. The indirect effect of LSKH behavior on employee OI was examined using the bootstrapping approach (n = 5,000) with 95% confidence intervals (CI) for the indices.

Findings

Findings show that LSKH behavior has a negative impact on employee OI through SIC perceptions. Additionally, a moderation analysis indicates that the employee trait agreeableness strengthens the negative relationship between SIC and OI as well as the indirect relationship between LSKH behavior and employee OI.

Originality/value

While previous studies mainly focused on employee knowledge-hiding behavior, this study extends this nascent stream of literature by investigating the impact of this behavior at the leader’s level in the Egyptian cultural context. The results provide insights into the consequences of this type of behavior on important outcomes, namely, SIC and OI.

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Journal of Knowledge Management, vol. 26 no. 6
Type: Research Article
ISSN: 1367-3270

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Article
Publication date: 7 May 2024

Gangting Huang, Qichen Wu, Youbiao Su, Yunfei Li and Shilin Xie

In order to improve the computation efficiency of the four-point rainflow algorithm, a new fast four-point rainflow cycle counting algorithm (FFRA) using a novel loop iteration…

84

Abstract

Purpose

In order to improve the computation efficiency of the four-point rainflow algorithm, a new fast four-point rainflow cycle counting algorithm (FFRA) using a novel loop iteration mode is proposed.

Design/methodology/approach

In this new algorithm, the loop iteration mode is simplified by reducing the number of iterations, tests and deletions. The high efficiency of the new algorithm makes it a preferable candidate in fatigue life online estimation of structural health monitoring systems.

Findings

The extensive simulation results show that the extracted cycles by the new FFRA are the same as those by the four-point rainflow cycle counting algorithm (FRA) and the three-point rainflow cycle counting algorithm (TRA). Especially, the simulation results indicate that the computation efficiency of the FFRA has improved an average of 12.4 times compared to the FRA and an average of 8.9 times compared to the TRA. Moreover, the equivalence of cycle extraction results between the FFRA and the FRA is proved mathematically by utilizing some fundamental properties of the rainflow algorithm. Theoretical proof of the efficiency improvement of the FFRA in comparison to the FRA is also given.

Originality/value

This merit makes the FFRA preferable in online monitoring systems of structures where fatigue life estimation needs to be accomplished online based on massive measured data. It is noticeable that the high efficiency of the FFRA attributed to the simple loop iteration, which provides beneficial guidance to improve the efficiency of existing algorithms.

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Article
Publication date: 27 February 2023

Ali A. Ali, H. Abd El-Wahab, Moustafa S. Abusaif, Ahmed Ragab, Omar A. Abdel-Jaid, E.A. Eldeeb and Yousry A. Ammar

The paper aims to the preparation of novel disperse dye based on azo salicylaldehyde derivatives TF-A [2-hydroxy-5-((3-(trifluoromethyl)phenyl)diazenyl)benzaldehyde] and full…

205

Abstract

Purpose

The paper aims to the preparation of novel disperse dye based on azo salicylaldehyde derivatives TF-A [2-hydroxy-5-((3-(trifluoromethyl)phenyl)diazenyl)benzaldehyde] and full evaluation of their use as disperse dye TF-ASC [bis 2-hydroxy-5-((3-(trifluoromethyl)phenyl)diazenyl)benzaldehyde Schiff base with 4,4'-methylenedianiline] for dyeing polyester fabric at various conditions.

Design/methodology/approach

The dispersed dye was synthesized via Schiff base condensation in the presence of ceric ammonium nitrate cerium ammonium nitrate 10 mmole% as an eco-friendly catalyst at room temperature. The chemical structure of the prepared dye was characterized via elemental analysis, Fourier-transform infrared spectroscopy, 1H- and 13 C-NMR spectroscopic analysis tools. This study thoroughly examined the dyeing of disperse dye TF-ASC on polyester at various conditions. The characteristics of dyed polyester fabric were measured by colour measurements, as well as light, washing, crock fastness and finally, colour strength. The discrete fourier transform (DFT) theoretical studies, including EHOMO, ELUMO and optimized geometrical structure, were assumed and discussed in detail.

Findings

The results showed that the synthesized organic dye TF-ASC was highly functional and appropriate for this kind of dyeing method. The dyeing fabrics obtained from disperse dye TF-ASC, properties possess high colour strength as well as good overall fastness properties. These dyes had a high affinity for polyester fabric, with just a tiny change in dye affinity when the pH was changed, even under alkaline circumstances. The dye levelness and shade depth of the colour results were good, and there were a variety of hues from light brownish yellow to deep brownish yellow. The results obtained from DFT computational studies such as EHOMO, ELUMO, optimized structure, diploe moment µ and electrophilicity index deduced that prepared organic dye TF-ASC is more applicable as a dispersed dye.

Originality/value

This research is significant because it provides a new dye for dyeing polyethylene terephthalate fibres with exceptional brightness and levelness; the method of preparation is a useful pathway due to its being known as a green chemistry method.

Details

Pigment & Resin Technology, vol. 53 no. 5
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 3 April 2017

Rupinder Singh and Sunpreet Singh

The present research work aims to study the friction coefficient in functionally graded rapid prototyping of Al–Al2O3 composite prepared via fused deposition modelling…

218

Abstract

Purpose

The present research work aims to study the friction coefficient in functionally graded rapid prototyping of Al–Al2O3 composite prepared via fused deposition modelling (FDM)-assisted investment casting (IC) process. The optimized settings of the process parameters (namely, filament proportion, volume of FDM pattern, density of FDM pattern, barrel finishing (BF) time, BF media weight and number of IC slurry layers) suggested in the present research work will help fabricate parts possessing higher frictional coefficient.

Design/methodology/approach

Initially, melt flow index (MFI) of two different proportions of Nylon6-Al–Al2O3 (to be used as an alternative FDM filament material) was tested on the melt flow indexer and matched with MFI of commercially used acrylonitrile–butadiene–styrene filament. After this, the selected proportions of Nylon6-Al–Al2O3 were prepared in the form of the FDM filament by using a single screw extruder. Further, this FDM filament has been used for developing sacrificial IC patterns in the existing FDM system which was barely finished to improve their surface finish. Castings developed were tested for their wear resistance properties on a pin-on-disc-type tribo-tester under dry conditions at sliding conditions to check their suitability as a frictional device for industrial applications. In the methodology part, Taguchi L18 orthogonal array was used to study the effect of selected process variables on the coefficient of friction (μ).

Findings

It has been found that filament proportion, volume of FDM pattern and density of FDM pattern have significantly affected the μ-values. Further, density of the FDM pattern was found to have 91.62 per cent contribution in obtaining μ-values. Scanning electron micrographs highlighted uniform distribution of Al2O3 particles in the Al-matrix at suggested optimized settings.

Practical implications

The present methodology shows the development of a functional graded material that consisted of surface reinforcement with Al2O3 particles, which could have applications for manufacturing friction surfaces such as clutch plates, brake drum, etc.

Originality/value

This paper describes the effect of process parameters on wear properties of the Al–Al2O3 composite developed as a functionally graded material by the FDM-based pattern in the IC process.

Details

Assembly Automation, vol. 37 no. 2
Type: Research Article
ISSN: 0144-5154

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