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Open Access
Article
Publication date: 30 May 2019

Judith H. Semeijn, Marjolein C.J. Caniëls and Daniël Kooistra

Sustainable employability is an important goal for individuals and organizations alike. However, scarce knowledge is available on possible cross-lagged relations of…

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Abstract

Purpose

Sustainable employability is an important goal for individuals and organizations alike. However, scarce knowledge is available on possible cross-lagged relations of resilience among police officers and different aspects of their sustainable employability over time. Based on assumptions of COR theory, the purpose of this paper is to test these relations in a two-wave design.

Design/methodology/approach

A total of 532 police officers participated in a time-lagged survey design (time interval of six months) concerning their resilience and relevant aspects, i.e., self-reported vitality, workability and organization-reported individual absenteeism rates. Data were analyzed with structural equation modeling.

Findings

Results indicate cross-lagged effects between resilience and vitality with an acceptable model fit. Thus, the level of resilience at T1 affected the level of vitality at T2 and vice versa. In addition, a nearly significant negative effect of vitality on T1 was found on absenteeism on T2.

Research limitations/implications

More measurements over time are needed to test reciprocal relations and possible gain spirals. Different samples are needed to assess generalizability. Cross-lagged effects may indicate a reciprocal relation between resilience and vitality that can be further facilitated.

Practical implications

For example, resilience can be addressed explicitly in training.

Originality/value

This study is the first to test the cross-lagged relations between resilience and indicators of sustainable employability among police officers. It is important to further study this for the sake of both police officers, as well as society as a whole.

Details

Policing: An International Journal, vol. 42 no. 6
Type: Research Article
ISSN: 1363-951X

Keywords

Article
Publication date: 13 January 2021

Ahmed Attia, Salim Guettala and Rebih Zaitri

The purpose of this paper is to implement the mathematical models to predict concretes physico-mechanical characteristics made with binary and ternary sands using a…

Abstract

Purpose

The purpose of this paper is to implement the mathematical models to predict concretes physico-mechanical characteristics made with binary and ternary sands using a mixture design method. It is a new technique that optimizes mixtures without being obliged to do a lot of experiments. The goal is to find the law governing the responses depending on mixture composition and capable of taking into account the effect of each parameter separately and in interaction between several parameters on the characteristics studied.

Design/methodology/approach

Mixture design method was used for optimizing concretes characteristics and studying the effects of river sand (RS), dune sand (DS) and crushed sand (CS) in combinations of binary system and ternary on workability, the compressive and flexural strengths of concretes at 7 and 28 days. A total of 21 mixtures of concrete were prepared for this investigation. The modeling was carried out by using JMP7 statistical software.

Findings

Mixture design method made it possible to obtain, with good precision, the statistical models and the prediction curves of studied responses. The models have relatively good correlation coefficients (R2 = 0.70) for all studied responses. The use of binary and ternary mixtures sands improves the workability and their mechanical strengths. The obtained results proved that concrete, based on binary mixture C15, presents the maximum compressive strength (MCS) on 28 day with an improvement of around 20%, compared to reference concrete (C21). For ternary mixtures, MCS on 28 day was obtained for the mixture C10 with an improvement of around 15% compared to C21. Increase in compressive strength during the progress of hydration reactions was accompanied by an increase in the flexural strength, but in different proportions.

Originality/value

The partial incorporation of DS (= 40%) in the concrete formulation can provide a solution for some work in the southern regions of country. In addition, the CS is an interesting alternative source for replacing 60% of RS. The concrete formulation based on local materials is really capable of solving the economic and technical problems encountered in the building field, as well as environmental problems. Local resources therefore constitute an economic, technological and environmental alternative.

Details

World Journal of Engineering, vol. 18 no. 2
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 13 September 2021

Vijaya Prasad B., Arumairaj Paul Daniel, Anand N. and Siva Kumar Yadav

Concrete is a building material widely used for the infrastructural development. Cement is the binding material used for the development of concrete. It is the primary…

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Abstract

Purpose

Concrete is a building material widely used for the infrastructural development. Cement is the binding material used for the development of concrete. It is the primary cause of CO2 emission globally. The purpose of this study is to develop sustainable concrete material to satisfy the present need of construction sector. Geopolymer concrete (GPC) is a sustainable concrete developed without the use of cement. Therefore, investigations are being conducted to replace the cement by 100% with high calcium fly ash (FA) as binding material.

Design/methodology/approach

High calcium FA is used as cementitious binder, sodium hydroxide (NaOH) and sodium silicates (Na2SiO3) are used as alkaline liquids for developing the GPC. Mix proportions with different NaOH molarities of 4, 6, 8 and 10 M are considered to attain the appropriate mix. The method of curing adopted is ambient and oven curing. Workability, compressive strength and microstructure characteristics of GPC are analysed and presented.

Findings

An increase of NaOH in the mix decreases the workability. Compressive strength of 29 MPa is obtained for Mix-I with 8 M under ambient curing. A polynomial relationship is obtained to predict the compressive strength of GPC. Scanning electron microscope analysis is used to confirm the geo-polymerisation process in the microstructure of concrete.

Originality/value

This research work focuses on finding some alternative cementitious material for concrete that can replace ordinary portland cement (OPC) to overcome the CO2 emission owing to the utilisation of cement in the construction industry. An attempt has been made to use the waste material (high calcium FA) from thermal power plant for the production of GPC. GPC concrete is the novel building material and alternative to conventional concrete. It is the ecofriendly product contributing towards the improvement of the circular economy in the construction industry. There are several factors that affect the property of GPC such as type of binder material, molarity of activator solution and curing condition. The novelty of this work lies in the approach of using locally available high calcium FA along with manufactured sand for the development of GPC. As this approach is rarely investigated, to prove the attainment of compressive strength of GPC with high calcium FA, an attempt has been made during the present investigation. Other influencing parameter which affects the strength gain has also been analysed in this paper.

Details

Journal of Engineering, Design and Technology , vol. 20 no. 2
Type: Research Article
ISSN: 1726-0531

Keywords

Article
Publication date: 12 October 2015

Nihel Chabrak

The purpose of the paper is to propose a model of integrity to help assess corporate responsiveness to this new wave of pressure in the backdrop of the prevailing…

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Abstract

Purpose

The purpose of the paper is to propose a model of integrity to help assess corporate responsiveness to this new wave of pressure in the backdrop of the prevailing Shareholder Value Maximization doctrine. In a context of ecological crisis, sustainability is considered in an intergenerational perspective on well-being. Nations are required to maintain the productive base, composed of manufactured, natural and human capitals, to continue producing future generations’ well-being. Such macroeconomic challenges require businesses to contribute to human and natural capitals’ conservation.

Design/methodology/approach

This paper applies the integrity model to the historical case of the New Lanark mills from Owen’s (1991/1813-1816) new view of society. Owen’s deeds are compared to his promises in light of community expectations in that time to assess Owen’s commitment to social responsibility through “his honoring his word”.

Findings

The findings show the importance of the concept of “workability” for a business to create an opportunity set for “performance”. Such workability is determined by the business being a person of integrity.

Research limitations/implications

Future researches are invited to use this model to build empirical evidence of corporate irresponsibility in dealing with the new challenges.

Practical implications

This paper’s contribution resides in the capacity to uncover any attempt by businesses to subsume their corporate social responsibility and sustainability commitment to the doxic shareholder value maximization (SVM) ideology.

Social implications

The findings recall the importance for corporate activities to be re-embedded in their social and ecological contexts. This requires an overhaul of the business logic.

Originality/value

The originality of the model of integrity resides in its simplicity and practicality.

Details

Society and Business Review, vol. 10 no. 3
Type: Research Article
ISSN: 1746-5680

Keywords

Article
Publication date: 17 March 2022

Mudasir Peerzada, Khan Adnan, Basrah Bilal, Riyaz Janees, Bazila Qazi and Naqash Ahmed Javed

The purpose of this paper is to study the effect of nano alumina (Al2O3) on the properties of fresh concrete, hardened concrete and microstructure of concrete incorporated…

Abstract

Purpose

The purpose of this paper is to study the effect of nano alumina (Al2O3) on the properties of fresh concrete, hardened concrete and microstructure of concrete incorporated with high range water reducer (HRWR). This initiative was taken to improve characteristic properties of concrete using nano alumina because nano alumina can be easily be manufactured from a scrap of industrial aluminum products, so its incorporation in concrete will not only reduce industrial aluminum waste but will also change the morphology of concrete at the microstructural level.

Design/methodology/approach

To accomplish the objectives of the research, four different concrete mixes with the constant water–cement ratio (W/C) and superplasticizer (SP) content 0.4 and 0.6% by weight of cement, respectively, were prepared, whereas nano alumina content was altered by 0.3% and 0.4% by weight of cement. Fresh property of concrete was analyzed by using slump cone test, whereas hardened properties of concrete were analyzed through compression test and flexural strength test. The interaction of nano alumina with concrete composite was evaluated using an X-ray diffraction test.

Findings

It was observed that 0.6% superplasticizer by weight of cement increased workability by 22% but with the addition of 0.3%, nano alumina by weight of cement workability decreased by 31%. Compressive strength increased by 4.88% with the addition of 0.6% superplasticizer but with the addition of 0.3% nano alumina by weight of cement compressive strength increased by 18.60%. Also, flexural strength increased by 1.21% with the addition of 0.6% superplasticizer by weight of cement but with the addition of 0.3% nano alumina by weight of cement flexural strength increased by 8.76%. With the addition of superplasticizer, alite and belite phases remained un-hydrated but with the addition of nano alumina alite phase was hydrated while belite phase was un-hydrated. The size of belite crystals in mixes having nano alumina was less than that of mix having 0.6% superplasticizer. Also with the addition of nano alumina, a calcium aluminum silicate phase was formed which was responsible for the increment of strength in mixes having nano alumina.

Originality/value

Incorporation nano alumina (Al2O3) in concrete will not only reduce industrial aluminum waste but will also reduce CO2 emission. Nano alumina (Al2O3) also changes morphology of concrete at micro structural level.

Details

World Journal of Engineering, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 5 June 2017

Richard Ohene Asiedu

The quest to reduce the cost of concrete which is a major construction input has prompted investigations into assessing the suitability of alternative sources of…

Abstract

Purpose

The quest to reduce the cost of concrete which is a major construction input has prompted investigations into assessing the suitability of alternative sources of conventional materials. This paper aims to report the compressive strength and workability of lateritic gravel used as all-in aggregate for concrete production.

Design/methodology/approach

Three prescribed mixes from all-in aggregate concrete were compared with concrete from lateritic gravel. The paper investigated the variation in strength of four different mixes – 100: 0, 90: 10, 80: 20 and 70: 30 – when portions of the lateritic gravel were replaced with pit sand, respectively, using varying water cement ratios to achieve optimal workability.

Findings

The density and compressive strength of each cube was measured on the 7th and 28th test dates. An increase in slump and compressive strength was observed in the lateritic concrete, as portions of the lateritic gravel were replaced with sand. However, the rate of increase in the compressive strength tended to decrease with increase in part replacement of lateritic gravel with sand indicating that there was a threshold of percentage of sand increase after which the compressive strengths are likely to decrease. This work never reached this threshold, but it is estimated to be about 40 per cent.

Research limitations/implications

Investigations focused on lateritic gravel sampled from two sites to represent samples from both the forest and savannah belt.

Practical/implications

Lateritic gravel can be used as all-in aggregate for non-structural concrete.

Originality/value

The compressive strengths achieved were better than those for the available normal all-in aggregate used.

Details

Journal of Engineering, Design and Technology, vol. 15 no. 03
Type: Research Article
ISSN: 1726-0531

Keywords

Article
Publication date: 1 August 2001

Paul Hathaway

People often say that working to expand opportunities in rural areas is one of the greatest challenges faced by mental health services. Paul Hathaway describes a uniquely…

Abstract

People often say that working to expand opportunities in rural areas is one of the greatest challenges faced by mental health services. Paul Hathaway describes a uniquely individualised way of working that enables service users to participate in and contribute to the communities in which they live, while at the same time improving their skills and employability.

Details

A Life in the Day, vol. 5 no. 3
Type: Research Article
ISSN: 1366-6282

Article
Publication date: 24 May 2022

Jin Hong Tan, Siaw-Chuing Loo, Nurshuhada Zainon, Nur Mardhiyah Aziz and Faizul Azli Mohd Rahim

Although building information modelling (BIM) brings various benefits and open up the construction industry to many new possibilities, it is not without some challenges…

Abstract

Purpose

Although building information modelling (BIM) brings various benefits and open up the construction industry to many new possibilities, it is not without some challenges. Blockchain has the potential to resolve some of these problems. It has shown that blockchain and BIM can potentially work together in bringing various benefits to all project stakeholders. However, there is a lack of research and knowledge in relation to blockchain-based BIM. Therefore, the purpose of this study is to close this gap by looking into the potential functionality and workability of blockchain within a BIM environment.

Design/methodology/approach

A four-stage preferred reporting items for systematic reviews and meta-analyses systematic literature review technique has been used to review the blockchain- and BIM-related information sources published. A total of 53 journal articles, 13 books and 27 other resources including that of reports and websites have been included in this paper.

Findings

Blockchain-based BIM has countless possibilities, ranging from simple tasks such as tracking of orders to automation of construction payment claims. The literatures have suggested that the several weaknesses that BIM possesses including trust issue, asset ownership issue and data reliability issue could be resolved by incorporating blockchain into its processes.

Originality/value

Because of the lack of researches on the workability of blockchain and BIM, this paper aims to close this gap by proposing a framework for the interaction between blockchain and BIM for a typical building project. This paper has reviewed a substantial amount of currently available knowledge on blockchain-based BIM and its relevancy to the construction industry. This paper believes that the information could be of use to potential BIM tools maker and the construction industry for the betterment of BIM implementation throughout a project life cycle.

Details

Journal of Facilities Management , vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1472-5967

Keywords

Article
Publication date: 25 April 2022

Hadji Ben Salah, Benamara Dalila and Taallah Bachir

This paper aims to express a mathematical model that predicts the effect of mineral additives on the physical–mechanical properties of high-performance sand concrete…

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Abstract

Purpose

This paper aims to express a mathematical model that predicts the effect of mineral additives on the physical–mechanical properties of high-performance sand concrete (HPSC), using SAS's JMP7 statistical analysis software.

Design/methodology/approach

A mixture design modeling approach is applied to sand concrete (SC) for optimizing mixtures without being obliged to do a lot of experiments, where the cement is partially replaced with two mineral additives silica fume (SF) and blast furnace slag (BFS) in proportions as high as 20% of the mass. A total of 15 mixtures of sand concrete is prepared in the laboratory using this analytical technique in combinations with binary and ternary systems to estimate the workability and the compressive strength (CS) of sand concrete at 7 and 28 days.

Findings

The results obtained showed that the use of derived models based on the experimental design approach greatly assisted in understanding the interactions between the various parameters of the studied mixtures; the mathematical models present excellent correlation coefficients (R² = 0.96 for CS7 days, R² = 0.93 for CS28 days and R² = 0.95 for slump) for all studied responses. Moreover, it was also found that the inclusion of additives (SF and BFS) in binary mixture SC12 and ternary mixtures SC8 leads to a significant improvement in mechanical strength compared to reference sand concrete SC15. These results give the possibility to obtain a formulation of HPSC.

Originality/value

This paper shows the possibility of manufacturing high-performance sand-concrete with good compressive strength; the developed mathematical model by using SAS's JMP7 statistical analysis software allowed us to reach a strength compression value of about 60 MPa, in 28 days, by replacing 10% of the cement weight with silica fume. Furthermore, with partial replacement of the cement weight (15%) with two additions such as silica fume (10%) and blast furnace slag (5%), a 58 MPa of compressive strength can be achieved, without overlooking the fact that this can be a key economic and environmental alternative.

Details

World Journal of Engineering, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1708-5284

Keywords

Book part
Publication date: 17 January 2022

Tamai A. Johnson

Work experience helps develop skills necessary for life after high school. The California WorkAbility 1 (WA1) Program was developed to improve post-secondary outcomes for…

Abstract

Work experience helps develop skills necessary for life after high school. The California WorkAbility 1 (WA1) Program was developed to improve post-secondary outcomes for students with disabilities by providing temporary employment to students. Teacher experiences and perspectives reveal benefits and challenges of the WA1 Program. Success of the program is measured by how many student participants are hired by the employer after internship hours are completed. Challenges include funding and development of an equitable process for student selection. This chapter discusses strategies and recommendations for developing an effective work-experience program, including, acquiring and appropriating funds, staff placement, collaboration, equitable access, and education of all stakeholders.

Details

Transition Programs for Children and Youth with Diverse Needs
Type: Book
ISBN: 978-1-80117-102-1

Keywords

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