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1 – 10 of 776Yijiang Peng, Xiyun Chen, Liping Ying and Mahmoud M.A. Kamel
Based on the base force element method, a two-dimensional random circle aggregate model with Monte Carlo principle is proposed to carry out research on softening curve in…
Abstract
Purpose
Based on the base force element method, a two-dimensional random circle aggregate model with Monte Carlo principle is proposed to carry out research on softening curve in meso-level.
Design/methodology/approach
The meso-level structure of recycled concrete is considered as the five-phase materials composed of aggregate, old interfacial transition zone, old mortar, new interfacial transition zone and new mortar. A multi-polyline damage model is adopted to describe the nonlinear mechanical behavior of recycled concrete material. The destruction state of the element is determined by the first strength theory. The research studies on damage process of recycled concrete under the loading conditions of uniaxial tension were established using the base force element method.
Findings
The softening curves of recycled concrete are obtained, which are in good agreement with experiment results. Simulation results show that the macroscopic mechanical properties and failure mechanism can analyze more reasonably from mesoscopic structure. Besides that, it can be investigated from the numerical results of the size effect in recycled concrete through the mesoscopic heterogeneity. Furthermore, the form of aggregate distribution has influence on the crack path but little effect on the tensile strength of recycled concrete.
Originality/value
The results show that the base force element method has been successfully applied to the study of softening curve of recycled concrete under uniaxial tension.
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Majid Jaraiedi and Wafik H. Iskander
Signal Detection Theory (SDT) has recently been used to evaluate the performance of imperfect inspectors. SDT model is based on a priori probabilities and perceived payoffs and…
Abstract
Signal Detection Theory (SDT) has recently been used to evaluate the performance of imperfect inspectors. SDT model is based on a priori probabilities and perceived payoffs and penalties to study inspectors′ behaviour. In this article, Bayes′ theorem is used to compute posterior probabilities of the two types of inspection error. These posterior probabilities give rise to the definition of Receiver Analysis Curves (RAC), which depict the “after the facts” consequences of inspection error. A cost model is also developed that reflects the true benefits and costs of inspection accuracy to the organisation.
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Karen McBride, Roza Sagitova and Olga Cam
This paper explores the reporting of the Russian American Company (RAC), from 1840 to 1863. Trading in fur, company fears of animal extinctions viewed from a monetary perspective…
Abstract
Purpose
This paper explores the reporting of the Russian American Company (RAC), from 1840 to 1863. Trading in fur, company fears of animal extinctions viewed from a monetary perspective led to early extinction reporting practice. These were not altruistic reports; they were generated by a wish to use natural resources. Despite the motivations, these reports present an example of successful extinction management by a for-profit company and a workable example of emancipatory extinction accounting.
Design/methodology/approach
Using thematic analysis, this study demonstrates how moving from transparency to accountability driven accounting can assist in biodiversity reporting, by exploring this historical business case of extinction management through the lens of Atkins and Maroun's (2018) extinction framework.
Findings
The application of the framework to the RAC's set of reports indicates that this offers a viable proposal for development of extinction management, providing a reporting tool for a for-profit company.
Originality/value
Exploring RAC's reports focusing on their extinction management processes and reporting, the paper contributes to the contemporary debate on the development of extinction reporting frameworks. These historical examples of extinction accounting, show extinction management and reporting is not a unique contemporary development in accounting. The research uses historical data as the empirical foundation for exploring applicability and further development of this extinction framework.
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Liping Ying, Yijiang Peng and Mahmoud M.A. Kamel
Based on the random aggregate model of recycled aggregate concrete (RAC), this paper aims to focus on the effect of loading rate on the failure pattern and the macroscopic…
Abstract
Purpose
Based on the random aggregate model of recycled aggregate concrete (RAC), this paper aims to focus on the effect of loading rate on the failure pattern and the macroscopic mechanical properties.
Design/methodology/approach
RAC is regarded as a five-phase inhomogeneous composite material at the mesoscopic level. The number and position of the aggregates are modeled by the Walraven formula and Monte–Carlo stochastic method, respectively. The RAC specimen is divided by the finite-element mesh to establish the dynamic base force element model. In this model, the element mechanical parameters of each material phase satisfy Weibull distribution. To simulate and analyze the dynamic mechanical behavior of RAC under axial tension, flexural tension and shear tension, the dynamic tensile modes of the double-notched specimens, the simply supported beam and the L specimens are modeled, respectively. In addition, the different concrete samples are numerically investigated under different loading rates.
Findings
The failure strength and failure pattern of RAC have strong rate-dependent characteristics because of the inhomogeneity and the inertial effect of the material.
Originality/value
The dynamic base force element method has been successfully applied to the study of recycled concrete.
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Flavia Oliveira do Prado Vicentin, Simone Vasconcelos Ribeiro Galina, Marlon Fernandes Rodrigues Alves and Adriana Backx Noronha Viana
Prior research suggests that organizational alliances' contribution to innovation performance is conditional to absorptive capacity (AC). Instead of an antecedent of alliances, in…
Abstract
Purpose
Prior research suggests that organizational alliances' contribution to innovation performance is conditional to absorptive capacity (AC). Instead of an antecedent of alliances, in this study, the authors conceptualize and evaluate AC as an outcome of alliance intensity.
Design/methodology/approach
The authors tested their theoretical framework using multivariate statistical analysis on data collected from a survey applied to dedicated biotechnology firms (DBFs) from three countries: Brazil, Portugal and Spain.
Findings
First, the results show that whereas the high alliance intensity effect is positive and stronger on RAC, it is negative and weaker on PAC. Second, the alliance intensity effect on RAC is strengthened when firms have alliances only in their home country and the top manager does not have both academic and managerial experiences.
Practical implications
The authors’ study suggests as implications for DBFs: (1) firms should form alliances to develop AC, (2) firms should consider alliances for improving AC when top managers' expertise is not diverse, and (3) firms should consider only alliances with national partners as a differential for AC development.
Originality/value
This research contributes to the literature of dynamic capabilities, AC, alliances and innovation management by providing empirical validation for key contingencies surrounding the benefits of alliances as an antecedent of AC.
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Emmanuel Ejiofor Anike, Messaoud Saidani, Eshmaiel Ganjian, Mark Tyrer and Adegoke Omotayo Olubanwo
This paper aims to review the effect of using recycled aggregates (RA) on the properties of recycled aggregate concrete (RAC) following the steady rise in global demand for…
Abstract
Purpose
This paper aims to review the effect of using recycled aggregates (RA) on the properties of recycled aggregate concrete (RAC) following the steady rise in global demand for concrete and the large generation of construction and demolition waste.
Design/methodology/approach
This study reviewed relevant literature of research work carried out by previous researchers, leading to a deeper understanding of the properties of both RA and RAC. The properties of RA and RAC reported in the various studies were then compared to their corresponding natural aggregate (NA) and natural aggregate concrete, as well as the specifications provided in different codes of practice. In addition, the mix design methods appropriate to RAC and the cost implication of using RA were reviewed.
Findings
Findings show that the contribution of RA to strength appears inferior in comparison to NA. The shortcoming is attributed to the mortar attached to the RA, which raises its water absorption capacity and lowers its density relative to those of NA. However, it has been reported that the use of regulated quantity of RA, new mixing and proportioning methods, the addition of admixtures and strengthening materials such as steel fibres, can improve both mechanical and durability properties of RAC. Cost evaluation also showed that some savings can be realized by using RA instead of NA.
Originality/value
This research serves as a guide for future works and suggests that the use of RA as aggregate in new concrete is technically possible, depending on the mix design method adopted.
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Examines a definition of hotels and the number of hotels in thecountries of the UK. Indicates by country the proportions of hotel stockrepresented by the major grading schemes and…
Abstract
Examines a definition of hotels and the number of hotels in the countries of the UK. Indicates by country the proportions of hotel stock represented by the major grading schemes and guides. Analyses the schemes by number and quality of grade where appropriate, and each category by its share of the country′s hotel stock. Explains the difficulties of comparison between grades of different schemes, concluding that a percentage share of grades should be employed. Indicates with equivalence tables percentage shares of quality grades for the major comparable schemes. Concludes that although the numerical comparisons can be criticized because of minor differences in the schemes, a foundation is provided for more meaningful comparisons than has previously existed.
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Lijuan Shi, Zuoning Jia, Huize Sun, Mingshu Tian and Liquan Chen
This paper aims to study the affecting factors on bird nesting on electronic railway catenary lines and the impact of bird nesting events on railway operation.
Abstract
Purpose
This paper aims to study the affecting factors on bird nesting on electronic railway catenary lines and the impact of bird nesting events on railway operation.
Design/methodology/approach
First, with one year’s bird nest events in the form of unstructured natural language collected from Shanghai Railway Bureau, the records were structured with the help of python software tool. Second, the method of root cause analysis (RCA) was used to identify all the possible influencing factors which are inclined to affect the probability of bird nesting. Third, the possible factors then were classified into two categories to meet subsequent analysis separately, category one was outside factors (i.e. geographic conditions related factors), the other was inside factors (i.e. railway related factors).
Findings
It was observed that factors of city population, geographic position affect nesting observably. Then it was demonstrated that both location and nesting on equipment part have no correlation with delay, while railway type had a significant but low correlation with delay.
Originality/value
This paper discloses the principle of impacts of nest events on railway operation.
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This paper considers whether professional codes of ethics are enforceable, legitimate, and just. In analyzing codes of ethics in this way, one must consider whether they exist to…
Abstract
This paper considers whether professional codes of ethics are enforceable, legitimate, and just. In analyzing codes of ethics in this way, one must consider whether they exist to benefit members of the profession, or society as a whole. The analysis shifts dramatically based on this question, as codes of ethics are typically created by members of the profession, not by representatives of the larger population, and where they are enforced, they are only enforced among members of the profession. However, professional codes of ethics have an impact on those outside the profession, or the larger society outside the smaller community that created them.
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This article surveys the literature dealing with theory and applications of life cycle costing (LCC). It deals with the literature published in the last 25 years and provides 667…
Abstract
This article surveys the literature dealing with theory and applications of life cycle costing (LCC). It deals with the literature published in the last 25 years and provides 667 references.