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Article
Publication date: 10 May 2019

Tarek Salama and Osama Moselhi

The purpose of this paper is to present a newly developed multi-objective optimization method for the time, cost and work interruptions for repetitive scheduling while considering…

Abstract

Purpose

The purpose of this paper is to present a newly developed multi-objective optimization method for the time, cost and work interruptions for repetitive scheduling while considering uncertainties associated with different input parameters.

Design/methodology/approach

The design of the developed method is based on integrating six modules: uncertainty and defuzzification module using fuzzy set theory, schedule calculations module using the integration of linear scheduling method (LSM) and critical chain project management (CCPM), cost calculations module that considers direct and indirect costs, delay penalty, and work interruptions cost, multi-objective optimization module using Evolver © 7.5.2 as a genetic algorithm (GA) software, module for identifying multiple critical sequences and schedule buffers, and reporting module.

Findings

For duration optimization that utilizes fuzzy inputs without interruptions or adding buffers, duration and cost generated by the developed method are found to be 90 and 99 percent of those reported in the literature, respectively. For cost optimization that utilizes fuzzy inputs without interruptions, project duration generated by the developed method is found to be 93 percent of that reported in the literature after adding buffers. The developed method accelerates the generation of optimum schedules.

Originality/value

Unlike methods reported in the literature, the proposed method is the first multi-objective optimization method that integrates LSM and the CCPM. This method considers uncertainties of productivity rates, quantities and availability of resources while utilizing multi-objective GA function to minimize project duration, cost and work interruptions simultaneously. Schedule buffers are assigned whether optimized schedule allows for interruptions or not. This method considers delay and work interruption penalties, and bonus payments.

Details

Engineering, Construction and Architectural Management, vol. 26 no. 7
Type: Research Article
ISSN: 0969-9988

Keywords

Article
Publication date: 3 August 2021

Tarek Salama, Ahmad Salah and Osama Moselhi

The purpose of this paper is to present a new method for project tracking and control of integrated offsite and onsite activities in modular construction considering practical…

1001

Abstract

Purpose

The purpose of this paper is to present a new method for project tracking and control of integrated offsite and onsite activities in modular construction considering practical characteristics associated with this type of construction.

Design/methodology/approach

The design embraces building information modelling and integrates last planner system (LPS), linear scheduling method (LSM) and critical chain project management (CCPM) to develop tracking and control procedures for modular construction projects. The developed method accounts for constraints of resources continuity and uncertainties associated with activity duration. Features of proposed method are illustrated in a case example for tracking and control of modular projects.

Findings

Comparison between developed schedule and Monte Carlo simulation showed that baseline duration generated from simulation exceeds that produced by developed method by 12% and 10% for schedules with 50% and 90% confidence level, respectively. These percentages decrease based on interventions of members of project team in the LPS sessions. The case example results indicate that project is delayed 5% and experienced cost overrun of 2.5%.

Originality/value

Developed method integrated LPS, LSM and CCPM while using metrics for reliability assessment of linear schedules, namely, critical percent plan complete (PPCcr) and buffer index (BI). PPCcr and BI measure percentage of plan completion for critical activities and buffer consumption, respectively. The developed method provides a systematic procedure for forecasting look-ahead schedules using forecasting correction factor Δt and a newly developed tracking and control procedure that uses PPCcr and BI. Quantitative cost analysis is also provided to forecast and monitor project costs to prove the robustness of proposed framework.

Details

Construction Innovation , vol. 21 no. 4
Type: Research Article
ISSN: 1471-4175

Keywords

Article
Publication date: 11 April 2023

Tarek Salama and Hisham Said

The purpose of this paper is to determine if companies in the modular and offsite construction (MOC) industry are agile or not and its level of application for agility principles…

Abstract

Purpose

The purpose of this paper is to determine if companies in the modular and offsite construction (MOC) industry are agile or not and its level of application for agility principles, which allows for quick responses to the increasingly dynamic nature of industry environments.

Design/methodology/approach

This paper proposes an agility assessment framework for MOC that uses 48 assessment attributes organized into four categories: metrics, drivers, enablers and capabilities. A questionnaire approach was used to disseminate the framework globally in 19 countries and synthesize its relevance to the MOC industry. The questionnaire had 55 complete responses, majority of respondents work in managerial positions for MOC manufacturing facilities and onsite general contractors.

Findings

It was found that the lowest metric score for adapting to change was for cost since controlling cost would be difficult for any changes required after the design freeze stage. The top agility driver was found to be the need to respond to the wide variety of customer expectations, while the lowest driver was the existence of competing priorities. The top agility enabler was vendor partnership, which can be related to current postpandemic supply chain disruptions. Regarding technological capabilities, Europe and the USA acquired better scores compared to Asia, Latin America and Africa.

Originality/value

This study contributes to the MOC body of knowledge by creating an agility assessment tool for MOC firms to analyze their agile approach and environment, identifying the preliminary importance of agility assessment attributes and determining significant agile differences between the main MOC industry groups.

Details

Construction Innovation , vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1471-4175

Keywords

Article
Publication date: 20 October 2021

Walid S. Abdel-Wakil, Tarek M. Salama, Elbadawy A. Kamoun, Farag Abd El Hai Ahmed, Wassem Hassan, Yaser A. El-Badry and Alaa Fahmy

This paper aims to synthesize new terpolymers by the emulsion polymerization technique composed of acrylamide-based polyurethane monomers (TPM and MPM) with different vinyl…

Abstract

Purpose

This paper aims to synthesize new terpolymers by the emulsion polymerization technique composed of acrylamide-based polyurethane monomers (TPM and MPM) with different vinyl acetate copolymer systems, such as vinyl acetate/butyl acrylate (VAc/BA), vinyl acetate/ethylhexyl acrylate (VAc/2-EHA) and vinyl acetate/vinyl ester of versatic acid (VAc/VEOVA 10) systems. The performance of the prepared terpolymers as binders in emulsion coatings and textile industries was investigated and compared with the analogous commercial ones.

Design/methodology/approach

New waterborne polyurethane-vinyl ester-vinyl acetate terpolymers with high solid content and nano-scale emulsions have been successfully synthesized in two steps. The polyurethane oligomers were prepared by the prepolymer method as the first step. The second step involved polymerization with different vinyl monomers. The synthesized terpolymers were characterized using FTIR, scanning electron microscope, thermogravimetric analysis, minimum film forming temperature and particle size analyzer methods.

Findings

The synthesized emulsion terpolymers have shown small particle sizes averaged of 70 nm and a narrow distribution range, along with good mechanical, thermal and chemical stabilities. The surface coating layers of the terpolymers also have some important in terms of smoothness, clarity and binding ability in water-based coating for up to 4425 scrub cycles at 30 GU. Further, a high potential application textile printing was achieved at high solid content of 47–50%.

Originality/value

The effects of different isocyanates and vinyl monomers on the properties of obtained emulsion coatings have been studied. The improvement consequences of the coating evaluation of the waterborne binders for emulsion paints have been described. The properties of polyester/cotton fabric print pigment printing of textiles appear to be most promising enhancements by using the prepared nanocomposites of PU-co-vinyl acetate-co-vinyl ester as waterborne binders. So that the prepared emulsions have the potential to replace solvent-based coatings as waterborne binders for both emulsion coating and textile printing applications.

Details

Pigment & Resin Technology, vol. 52 no. 1
Type: Research Article
ISSN: 0369-9420

Keywords

Abstract

Details

Journal of Intelligent Manufacturing and Special Equipment, vol. 4 no. 1
Type: Research Article
ISSN: 2633-6596

Article
Publication date: 1 March 2017

Gasser Gamil Abdel-Azim

The ideology of “Local Architecture” was about the religious experience, social and cultural interpretations non-awareness, and solutions for environmental and social problems…

Abstract

The ideology of “Local Architecture” was about the religious experience, social and cultural interpretations non-awareness, and solutions for environmental and social problems. This case aims at producing a compatible architecture for this society. The problem of the paper deals with the absence of the local heritage in contemporary architecture. Most of our buildings reflect western ideologies, and use the local vocabulary, as has happened in most of the Arab architecture, that deals directly with a language of shapes to create compatibility with the public. Hence, the aim of the paper is to link the variables that the contemporary architecture formulated with concepts of local architecture. To meet such aims, the research is pivot around two themes: Firstly, tackling how to extract the forces that lead to the contemporariness of local heritage and formalize the DNA of any local community (Culture, Community Aspiration, Climate, and Technology), as well as discussing some experience that dealt with local architecture. Secondly, discussing some recent trials that learned from the previous attempts through history. The attempts strongly re-activate the local architecture in the contemporary challenges, namely, the use of heritage forms as is to conform to environmental determinants, development of these forms using contemporary materials through the visions of local architecture, and employing high-tech solutions to achieve contemporary appropriateness within traditional ideologies. In the end, the paper presents new ideas of the local architecture that learned from the previous experiences in our Arab societies to meet the needs of today's Arab societies.

Details

Open House International, vol. 42 no. 1
Type: Research Article
ISSN: 0168-2601

Keywords

Article
Publication date: 27 May 2020

Marwa M. El-Ashmouni and Ashraf M. Salama

The purpose of this paper is to develop an analytical account on the contemporary architecture of Cairo with emphasis on the past three decades, from the early 1990s to the…

566

Abstract

Purpose

The purpose of this paper is to develop an analytical account on the contemporary architecture of Cairo with emphasis on the past three decades, from the early 1990s to the present. The paper critically analyses narratives of the plurality of “isms”, within architectural vocabulary and discourse, that resulted from the contextual particularities that shaped it.

Design/methodology/approach

Three lines of inquiry are envisioned as overarching aspects of architecture: the chronological, the interventional and the representational. These discussions are underpinned by the discourse of decolonialisation and cosmopolitanism, posited sequentially by Frantz Fanon in The Wretched of the Earth (1961), and Ulrich Beck in The Cosmopolitan Vision (2004). The analysis expands to interrogate these two notions as prelude for reflecting on representations of selected projects: The Smart Village (2001); the Great Egyptian Museum (2002), Al-Azhar Park (2005), American University in Cairo New Campus (2008/2009), and the New Administrative Capital (2018).

Findings

The investigation on the interventional and the representational levels via aspects of discursivity and contradictions highlights that decolonisation and cosmopolitanism are two inseparable facets in the architectural practice in Egypt’s 21st century. These indivisible notions are based on idiosyncratic core to human experience, which emerged from concurrent overturning historical and secular everyday life striving to suppress ideological supremacy.

Research limitations/implications

Further detailed examples can be developed to offer discerning elucidations relevant to both notions of cosmopolitanism and decolonialisation.

Originality/value

The paper offers novel theoretical analysis of Cairo’s most recent architecture. The reflection on the notions of decolonialisation and cosmopolitanism is a timely example of the complex cultural encounters that have shaped the Egyptian architecture, given the recent interventions by the “Modern State” that legitimised such notions.

Details

Open House International, vol. 45 no. 1/2
Type: Research Article
ISSN: 0168-2601

Keywords

Article
Publication date: 7 May 2019

Christine Adel, Mostaq M. Hussain, Ehab K.A. Mohamed and Mohamed A.K. Basuony

This paper aims to report on the quality of corporate social responsibility (CSR) disclosure in S&P Europe 350 companies. The paper also examines the impact of corporate…

3381

Abstract

Purpose

This paper aims to report on the quality of corporate social responsibility (CSR) disclosure in S&P Europe 350 companies. The paper also examines the impact of corporate governance structure and other firm-specific characteristics on the quality of CSR disclosure in European companies.

Design/methodology/approach

The paper uses a disclosure index adopted from Jizi et al. (2014). Moreover, the paper contributes to the CSR disclosure literature by developing a new index that includes all the aspects introduced by the Global Reporting Initiative version 4.The data of CSR reporting are manually collected from the firms’ reports. The population and sample of this study are related to 350 companies operating in 16 European countries. Tobit regression analysis is used to test the hypotheses.

Findings

The results reveal that directors’ ownership, the presence of a CSR committee and firm size positively affect the quality of CSR reporting. Further testing of the independent variables on each CSR sub-category is made. The CSR sub-categories used are, namely, community involvement, employees, environment, social product and service quality, supply chain sustainability and business ethics. The presence of a sustainability committee inside the company is the only factor that shows a strong positive effect on the disclosure of every CSR sub-category and the CSR inclusive index.

Research limitations/implications

The limitations of this research are that it focuses exclusively on the effect of the internal corporate mechanisms on the quality of CSR reporting; disregarding the economic, institutional, political and cultural factors that can play a role in influencing sustainability reporting of the companies.

Practical implications

Better CSR disclosure leads to the firm having a better image in the society; this, in turn, has implications on firm performance, attracting funds, as well as recruiting and retaining high profile employees. Stakeholders are placing cumulative significance to corporate transparency particularly in the area of CSR. Managers should exert more efforts into not only improving the disclosure of the various facts of CSR but also into using the various media available for disclosure. Companies should take the initiative of establishing a CSR committee to ensure effective formation and implementation of CSR policies and disclosure of CSR activities.

Social implications

The CRS research itself bears the merit of social implications. Moreover, the findings of this research pave the way for future researches to examine the effect of the adoption of global CSR initiatives and frameworks on the quality of CSR reporting.

Originality/value

This paper contributes to the CSR disclosure literature by developing a new index that includes all the aspects of CSR and exploring the relation between the rarely explored “presence of sustainability committee” and CSR disclosure, as well as testing a vast number of CSR sub-categories that is not extensively covered in previous studies. Moreover, the paper covers a large sample of companies across 16 European countries, in terms of their stand-alone sustainability reports, dedicated chapters of CSR in annual reports, integrated reports, website CSR information and any attachments/links provided on the websites for further CSR documents, brochures or data sheets.

Details

International Journal of Accounting & Information Management, vol. 27 no. 2
Type: Research Article
ISSN: 1834-7649

Keywords

Article
Publication date: 26 July 2023

Hamdy Mohamed Mohamed and Wael Sabry Mohamed

The study aims to assess the efficiency of nanocomposite to improve the properties of gap-filling materials for pottery artifacts.

Abstract

Purpose

The study aims to assess the efficiency of nanocomposite to improve the properties of gap-filling materials for pottery artifacts.

Design/methodology/approach

Five different pastes were used in the laboratory studies. The pastes consist mainly of pottery powder (grog), dental plaster, microballoons and an adhesive of Primal AC33, nano-silica and nano kaolinite in various concentrations. The prepared samples were subjected to accelerated heat and light aging. Besides, some investigations were used to evaluate the efficacy of the additive nanomaterials, such as TEM, digital and scanning electron microscopy microscopes. Contact angle, color change, shrinkage degree, physical properties and compressive strength tests were also conducted.

Findings

The results indicated that using Nano-silica considerably improves the mechanical strength and decreases the shrinkage of gap-filling materials. According to the results, a mixture of grog, microballoons and Primal AC33/Nano-silica Nanocomposites is the optimal gap-filling paste for archaeological pottery. Moreover, this paste showed a higher contact angle (120°), lower color change (ΔE = 2.62), lower shrinkage (3.3%), lower water absorption (3.36%), lower porosity (5.05%) and higher compressive strength (5124 N/mm2).

Originality/value

This paper attains to develop an economic polymer-nanocomposite that can be used with gap-filling materials for pottery artifacts.

Details

Pigment & Resin Technology, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 25 March 2024

Mostafa Abdel-Hamied, Ahmed A.M. Abdelhafez and Gomaa Abdel-Maksoud

This study aims to focus on the main materials used in consolidation processes of illuminated paper manuscripts and leather binding.

Abstract

Purpose

This study aims to focus on the main materials used in consolidation processes of illuminated paper manuscripts and leather binding.

Design/methodology/approach

For each material, chemical structure, chemical composition, molecular formula, solubility, advantages, disadvantages and its role in treatment process are presented.

Findings

This study concluded that carboxy methyl cellulose, hydroxy propyl cellulose, methyl cellulose, cellulose acetate, nanocrystalline cellulose, funori, sturgeon glue, poly vinyl alcohol, chitosan, chitosan nanoparticles (NPs), gelatin, aquazol, paraloid B72 and hydroxyapatite NPs were the most common and important materials used for the consolidation of illuminated paper manuscripts. For the leather bindings, hydroxy propyl cellulose, polyethylene glycol, oligomeric melamine-formaldehyde resin, acrylic wax SC6000, pliantex, paraloid B67 and B72, silicone oil and collagen NPs are the most consolidants used.

Originality/value

Illuminated paper manuscripts with leather binding are considered one of the most important objects in libraries, museums and storehouses. The uncontrolled conditions and other deterioration factors inside the libraries and storehouses lead to degradation of these artifacts. The brittleness, fragility and weakness are considered the most common deterioration aspects of illuminated paper manuscripts and leather binding. Therefore, the consolidation process became vital and important to solve this problem. This study presents the main materials used for consolidation process of illuminated paper manuscripts and leather bindings.

Details

Pigment & Resin Technology, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0369-9420

Keywords

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