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1 – 10 of 145Javad Babakhani and Farzad Veysi
The purpose of this article is to investigate the variables affecting heat transfer from the surfaces of a tall building and also the extent of the impact of each of them. Another…
Abstract
Purpose
The purpose of this article is to investigate the variables affecting heat transfer from the surfaces of a tall building and also the extent of the impact of each of them. Another purpose of this paper is to provide a suitable model for estimating the heat transfer coefficient of the external surfaces of the building according to the impact of variables.
Design/methodology/approach
In this study, the Taguchi's approach in the design of the experiments was used to reduce the number of experiments. Percent contributions factors into the overall and surface-averaged Nu of a square prism were obtained by the (ANOVA). The change in Nu by changing either of T, P, angle of attack and V were investigated by the (ANOM). The most significant factors affecting the value Nu were also identified to facilitate the design of thermal systems by eliminating the factors imposing no significant effect on the response in the molding phase. The set of conditions under which the air properties remained unchanged was identified. Five correlations were formulated to predict Nu.
Findings
Models used in BES, in which the effects of T, P, A and geometrical effects are not accounted for, are not reliable. The air pressure was found to impose no significant effect on the overall Nu of the considered square prism. Studied in the range of 274–303 K, the air temperature imposed a significant effect on the overall Nu. The results of ANOVA show the significant role of Re to predict Nu of tall buildings.
Originality/value
This article is taken from a doctoral dissertation.
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Ripendeep Singh Sidhu, Gurmeet Singh and Harjot Singh Gill
This empirical study aims to investigate the erosion wear performance of two different 3D-printed materials (acrylonitrile butadiene styrene [ABS] and polylactic acid [PLA]) with…
Abstract
Purpose
This empirical study aims to investigate the erosion wear performance of two different 3D-printed materials (acrylonitrile butadiene styrene [ABS] and polylactic acid [PLA]) with various micro textures. The two different textures (prism and square) were created over the surfaces of both materials by using the 3D-printed technique.
Design/methodology/approach
The erosion experiments on both materials were performed by using Ducom Erosion Jet Tester. Erosion tests were performed at four different impacting velocities (15, 30, 45 and 60 m/s) with the four different particle sizes (17, 39, 63 97 µm) at the impact angles (30°–90°) for the time duration of 5, 10, 15 and 20 min. The two different textures prism and cone were used for performing the erosion experiments. Taguchi’s orthogonal L16 (mixed level) was used to reduce the number of experiments and to determine the impact of these parameters on erosion wear performance of both 3D-printed materials.
Findings
The PLA with cone texture was found to be best (against erosion) than the ABS cone and prism textures due to their high hardness (68 HV). Also, the average signal to noise (S/N) ratio for PLA and ABS was measured as 56.4 and 44.4 dB, respectively. As the value of the S/N ratio is inversely proportional to the erosion rate, the PLA has the least erosion rate as compared to the ABS. The sequence of erosion wear influencing parameters for both materials was in the following order: velocity > erodent size > texture > impact angle > time interval.
Originality/value
Both PLA and ABS with different micro textures for erosion testing were studied with Taguchi’s optimization method, and the erosion mechanisms are well analyzed by using scanning electron microscopy and Image J techniques.
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Rawan Ramadan, Hassan Ghanem, Jamal M. Khatib and Adel M. ElKordi
The purpose of this paper is to check the feasibility of using biomaterial such as of Phragmites-Australis (PA) in cement paste to achieve sustainable building materials.
Abstract
Purpose
The purpose of this paper is to check the feasibility of using biomaterial such as of Phragmites-Australis (PA) in cement paste to achieve sustainable building materials.
Design/methodology/approach
In this study, cement pastes were prepared by adding locally produced PA fibers in four different volumes: 0%, 0.5%, 1% and 2% for a duration of 180 days. Bottles and prisms were subjected to chemical shrinkage (CS), drying shrinkage (DS), autogenous shrinkage (AS) and expansion tests. Besides, prism specimens were tested for flexural strength and compressive strength. Furthermore, a mathematical model was proposed to determine the variation length change as function of time.
Findings
The experimental findings showed that the mechanical properties of cement paste were significantly improved by the addition of 1% PA fiber compared to other PA mixes. The effect of increasing the % of PA fibers reduces the CS, AS, DS and expansion of cement paste. For example, the addition of 2% PA fibers reduces the CS, expansion, AS and DS at 180 days by 36%, 20%, 13% and 10%, respectively compared to the control mix. The proposed nonlinear model fit to the experimental data is appropriate with R2 values above 0.92. There seems to be a strong positive linear correlation between CS and AS/DS with R2 above 0.95. However, there exists a negative linear correlation between CS and expansion.
Research limitations/implications
The PA used in this study was obtained from one specific location. This can exhibit a limitation as soil type may affect PA properties. Also, one method was used to treat the PA fibers.
Practical implications
The utilization of PA fibers in paste may well reduce the formation of cracks and limit its propagation, thus using a biomaterial such as PA in cementitious systems can be an environmentally friendly option as it will make good use of the waste generated and enhance local employment, thereby contributing toward sustainable development.
Originality/value
To the authors best knowledge, there is hardly any research on the effect of PA on the volume stability of cement paste. Therefore, the research outputs are considered to be original.
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Harry J. Van Buren and Judith Schrempf-Stirling
Stakeholder capitalism has been proposed as an alternative way of thinking about business purpose and value creation. However, stakeholder capitalism can only work as an…
Abstract
Purpose
Stakeholder capitalism has been proposed as an alternative way of thinking about business purpose and value creation. However, stakeholder capitalism can only work as an alternative model of business if all stakeholders and their interests are visible to and taken seriously by managers. The purpose of this paper is to untangle the challenges that invisible, marginalized and powerless stakeholders pose for theorizing about stakeholder capitalism.
Design/methodology/approach
This paper is conceptual. The authors first briefly outline the promise of stakeholder capitalism for addressing pressing questions about value creation and stakeholder welfare. The authors then conceptualize stakeholder invisibility as the outcome of a particular stakeholder being both powerless and marginal through the prism of moral intensity theory and one of its elements: proximity. This study discusses the ways in which managers can make invisible stakeholders more visible in their decision-making.
Findings
For managers truly to manage for stakeholders, as anticipated by stakeholder capitalism, all stakeholders and stakeholder interests must be visible to them. This study analyzes why sometimes they are not, how they can be made more visible and why stakeholder visibility matters for stakeholder capitalism. This study proffers three principles for business practice: ethical commitments to reduce stakeholder invisibility, analyses of business strategies to surface the contributions of marginalized and invisible stakeholders and taking rights seriously.
Originality/value
This study provides a new perspective on stakeholder capitalism by linking the challenge in operationalizing it to the problems of stakeholder invisibility and marginality.
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Jamal Khatib, Lelian ElKhatib, Joseph Assaad and Adel El Kordi
The purpose of this paper is to examine the use of phragmites australis ash (PAA) in cementitious systems to achieve sustainable construction.
Abstract
Purpose
The purpose of this paper is to examine the use of phragmites australis ash (PAA) in cementitious systems to achieve sustainable construction.
Design/methodology/approach
In this paper, the properties of mortar containing PAA as partial cement replacement are determined. The PAA is produced through slow burning in a closed system to minimize the CO2 emission. A total of four mortar mixes are prepared with PAA replacement levels ranging from 0% to 30% by weight. The water to binder and the proportions of binder to sand are 0.55 and 1:3 by weight, respectively. The properties tested are density, compressive strength, flexural strength, ultrasonic pulse velocity, water absorption by total immersion and capillary rise. Testing is conducted at 1, 7, 28 and 90 days.
Findings
While there is a decrease in strength as the amount of PAA increases, there is strong indication of pozzolanic reaction in the presence of PAA. This is in agreement with the results reported by Salvo et al. (2015), where they found noticeable pozzolanic activities in the presence of straw ash, which is rich in SiO2 and relatively high K2O content. At 90 days of curing, there is a decrease of 5% in compressive strength at 10% PAA replacement. However, at 20% and 30% replacement, the reduction in compressive strength is 23% and 32%, respectively. The trend in flexural strength and ultrasonic pulse velocity is similar to that in compressive strength. The water absorption by total immersion and capillary rise tends to increase with increasing amounts of PAA in the mix. There seems to be a linear relationship between water absorption and compressive strength at each curing age.
Research limitations/implications
The Phragmites australis plant used in this investigation is obtained from one location and this present a limitation as the type of soil may change the properties. Also one method of slow burning is used. Different burning methods may alter the composition of the PAA.
Practical implications
This outcome of this research will contribute towards sustainable development as it will make use of the waste generated, reduce the amount of energy-intensive cement used in construction and help generate local employment in the area where the Phragmites australis plant grows.
Originality/value
To the best knowledge of the authors, the ash from the Phragmites australis plant has not been used in cementitious system and this research can be considered original as it examines the properties of mortar containing PAA. Also, the process of burning in a closed system using this material.
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This study aims to conceptualize, rethink and systematize methods used for measurement and evaluation (M&E) corporate communication.
Abstract
Purpose
This study aims to conceptualize, rethink and systematize methods used for measurement and evaluation (M&E) corporate communication.
Design/methodology/approach
The reflection is based on 462 key English-language books and papers devoted to M&E in the fields of corporate communication and public relations from the 1970th to 2023. Keywords in the titles and abstracts found the necessary materials. A critical analysis of the central concepts, models and methods described in the literature was conducted. As a result, a new model that unifies and structures the M&E toolkit is proposed for discussion.
Findings
Despite the significant contribution to developing a wide range of M&E models, they are still not perfect and universal. In addition, this system of approaches is continuously self-evolving and changing under the influence of digital innovations, so it requires steady rethinking and updating. On the other hand, most previous studies focused on communication management processes, losing focus on communication aspects. This led to the need for an alternative view based on proven theories to fill this gap. The proposed model combines quantitative and qualitative M&E methods for the five main components of corporate communication (communicator, audience, content, channels and result), covering a wide range of tools, from statistical and sociological research to big data analysis and neuro research.
Originality/value
This work contributes to developing the M&E theory of corporate communication, systematizing existing methods and opening new research perspectives. From a practical point of view, companies can use the presented approach for a more accurate and objective internal evaluation of the main components of corporate communication.
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I aimed to obtain a deeper insight into the link between supplier involvement in product development (SIPD), supplier relationship resilience and company performance.
Abstract
Purpose
I aimed to obtain a deeper insight into the link between supplier involvement in product development (SIPD), supplier relationship resilience and company performance.
Design/methodology/approach
To collect data, a survey among 500 Polish manufacturing companies was conducted. I used quantitative methods (structural equation modeling) to test several research hypotheses referring to a single supplier–customer relationship. Thanks to the use of multi-construct measurement of SIPD and supplier relationship resilience, the study provides detailed research results on the topic.
Findings
Collaborative practices implemented during SIPD increase procurement flexibility and decrease redundancy in the relationship with the involved supplier. Communication during SIPD increases supplier flexibility and procurement flexibility. Increased supplier flexibility and increased procurement flexibility in the relationship with the involved supplier as well as collaborative practices during SIPD positively impact company performance. I confirmed the indirect effect between communication during SIPD and company performance when the mediators are supplier flexibility and procurement flexibility. Decreased redundancy in relationship with involved supplier does not impact company performance.
Practical implications
Supply chain managers need to rethink SIPD practice to effectively ensure supply chain resilience (SCRES), especially in the face of the contemporary global crisis and black swans affecting the supplier base. My article provides important managerial insights into drivers of SCRES and company performance.
Originality/value
To the best of my knowledge, this research is among the first to conclude that SIPD does not have an unequivocally positive or direct impact on supplier relationship resilience. The research fills the gap by analyzing the impact of SIPD on two main SCRES elements. The study examines supplier relationship resilience, understood as flexibility and redundancy elements, in a single supplier–buyer relationship perspective. Thus, the presented considerations go beyond the traditional understanding of flexibility and redundancy in supplier relationship management, that is through the prism of double or multi sourcing and having back up-suppliers.
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Zeynep Fatma Niğdeli, Funda Gençer and İzzet Yüksek
The purpose of the study is to provide a dataset about geometrical constructions of early Ottoman tombs for conservation studies. Thus, a proposal for the restitution phase of the…
Abstract
Purpose
The purpose of the study is to provide a dataset about geometrical constructions of early Ottoman tombs for conservation studies. Thus, a proposal for the restitution phase of the damaged tombs aims to develop.
Design/methodology/approach
The study is composed of four phases. First, the representative plan and section drawings of early Ottoman Tombs were redrawn; second, a geometrical analysis was made, a proposal table was prepared for the restitution of the damaged tombs; and last, this table was applied to tomb examples and restitution drawings are verified with the original situation of the tombs.
Findings
Early Ottoman tombs may be interpreted through geometric shapes, including the square, circle, triangle, octagon, arsin grid and quadrature systems. The arsin grid system provides information about the position of the domes and the height of the drums and windows. Quadrature establishes the highest point of domes and entrances. The proposal table, developed from the obtained results, facilitated the identification of the original elements, including the dome, drum, window and portal. This information is crucial for conducting further studies on restitution.
Originality/value
The abundance and dispersed nature of tomb structures compared to other architectural designs pose challenges in their scholarly examination. The early Ottoman tombs, which experienced an increase in numbers following the Conquest of Istanbul, serve as the initial expressions and embodiments of novel architectural endeavors. Thus, the determination of design ideas of the early Ottoman tombs sheds light on Ottoman architectural practice, which has remained largely unknown and guided the conservation studies of the tombs that have lost their integrity and originality.
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To investigate the mechanical properties of geopolymer concrete at elevated temperatures.
Abstract
Purpose
To investigate the mechanical properties of geopolymer concrete at elevated temperatures.
Design/methodology/approach
The investigation involved studying the influence of partially replacing fly ash with ground granulated blast furnace slag (GGBS) at different proportions (5%, 10%, 15%, 20% and 25%) on the composition of the geopolymer. This approach aimed to examine how the addition of GGBS impacts the properties of the geopolymer material. The chemical NaOH was purchased from the local supplier of Jamshedpur. The alkali solution was prepared with a concentration of 12 M NaOH to produce the concrete. After several trials, the alkaline-to-binder ratio was determined to be 0.43.
Findings
The compressive strength values at 28 days for specimens FG1, FG2, FG3, FG4 and FG5 are 35.42 MPa, 41.26 MPa, 44.79 MPa, 50.51 MPa and 46.33 MPa, respectively. The flexural strength values at 28 days for specimens FG1, FG2, FG3, FG4 and FG5 are 5.31 MPa, 5.64 MPa, 6.12 MPa, 7.15 MPa and 6.48 MPa, respectively. The split tensile strength values at 28 days for specimens FG1, FG2, FG3, FG4 and FG5 are 2.82 MPa, 2.95 MPa, 3.14 MPa, 3.52 MPa and 3.31 MPa, respectively.
Originality/value
This approach allows for the examination of how the addition of GGBS affects the properties of the geopolymer material. Four different temperature levels were chosen for analysis: 100 °C, 300 °C, 500 °C and 700 °C. By subjecting the geopolymer samples to these elevated temperatures, the study aimed to observe any changes in their mechanical.
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Kirti Sood, Prachi Pathak, Jinesh Jain and Sanjay Gupta
Research in the domain of behavioral finance has proven that investors demonstrate irrational behavior while making investment decisions. In a similar domain, the primary…
Abstract
Purpose
Research in the domain of behavioral finance has proven that investors demonstrate irrational behavior while making investment decisions. In a similar domain, the primary objective of this research is to prioritize the behavioral biases that influence cryptocurrency investors' investment decisions in the Indian context.
Design/methodology/approach
A fuzzy analytic hierarchy process (F-AHP) was used to prioritize the behavioral factors impacting cryptocurrency investors' investment decisions. Overconfidence and optimism, anchoring, representativeness, information availability, herding, regret aversion, and loss aversion are among the primary biases evaluated in the present study.
Findings
The findings suggested that the two most important influential criteria were herding and regret aversion, with loss aversion and information availability being the least influential criteria. Opinions of family, friends, and colleagues about investment in cryptocurrency, the sale of cryptocurrencies that have increased in value, the avoidance of selling currencies that have decreased in value, the agony of holding losing cryptocurrencies for too long rather than selling winning cryptocurrencies too soon, and the purchase of cryptocurrencies that have fallen significantly from their all-time high are the most important sub-criteria.
Research limitations/implications
This survey only covered active cryptocurrency participants. Additionally, the study was limited to individual crypto investors in one country, India, with a sample size of 467 participants. Although the sample size is appropriate, a larger sample size might reflect the more realistic scenario of the Indian crypto market.
Practical implications
The study is relevant to individual and institutional cryptocurrency investors, crypto portfolio managers, policymakers, researchers, market regulators, and society at large.
Originality/value
To the best of the authors' knowledge, no prior research has attempted to explain how the overall importance of various criteria and sub-criteria related to behavioral factors that influence the decision-making process of crypto retail investors can be assessed and how the priority of focus can be established, particularly in the Indian context.
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