Search results

1 – 10 of over 4000
Article
Publication date: 6 June 2023

Wujiu Pan, Xianmu Li, Lele Sun, Hongxing Song and Minghai Wang

The purpose is to predict the distribution of the residual pretightening force of the bolt group under the action of any initial pretightening force, and to achieve the final…

Abstract

Purpose

The purpose is to predict the distribution of the residual pretightening force of the bolt group under the action of any initial pretightening force, and to achieve the final residual pretightening force as the target to solve the initial pretightening force value to be applied.

Design/methodology/approach

Based on the finite element method and the elastic interaction theory between bolt group, this paper establishes a prediction model for the residual pretightening force distribution of bolt group for one-step pretightening and multi-step pretightening of gasketless flange connection systems. In addition, using the general modeling method given in this paper, the prediction model of residual pretightening force of long plate bolt connection system is established, and compared with reference, which fully proves the effectiveness and universality of the general prediction model of residual pretightening force of bolt group.

Findings

The appropriate pretightening sequence, increasing the number of pretightening steps and variable amplitude loading can effectively reduce the influence of elastic interaction and improve the uniformity of residual pretightening force of the bolt group. And the selection of material, number of bolts and connected thickness of bolt connection system also has a great influence on the distribution of residual pretightening force of bolt groups.

Originality/value

The general prediction model for the residual pretightening force of bolt group of connecting structural components considering elastic interaction given in this paper can provide a reference for the design and optimization of the bolt assembly process of the rotor system and the casing system in aero-engine and the prediction of the performance of the connecting system.

Details

Engineering Computations, vol. 40 no. 4
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 7 September 2021

Alolote Amadi

The study is carried out to analytically reconnoiter geotechnical index properties of subgrade soils as key variables that shape the cost profile of road infrastructure projects…

Abstract

Purpose

The study is carried out to analytically reconnoiter geotechnical index properties of subgrade soils as key variables that shape the cost profile of road infrastructure projects in a tropical geographic setting with starkly heterogenous ground conditions.

Design/methodology/approach

Using the Niger Delta region, as a point of reference, data on geotechnical index properties of subgrade soils at spatially dispersed locations for 61 completed highway projects are collated. Exploratory statistical tests were carried out to infer significant associations with final project costs before regression analysis. Regression analysis is principally deployed as an explanatory analytical tool, relevant to quantify the sensitivity of highway project costs to the individual and collective impact of geotechnical variables.

Findings

Several parameters of expansivity and compressibility exhibited significantly strong associations with the final costs recorded on the highway projects. The statistical analysis further established a cause-effect relationship, whereby small changes in the geotechnical properties of sub-grade soils at project locations, would result in disproportionately large changes in the cost of road construction.

Practical implications

The study findings provide insight into the sensitivity of road construction costs to geotechnical variables, which can serve as a useful input in financial risk analysis for development appraisal and the generation of location adjustment factors.

Originality/value

The study statistically demonstrates location-induced construction cost profiles, triggered in response to the spatial geotechnical variability and occurrence of problem subgrade soils in the humid tropics, which may be different from those traditionally established in studies of cold and temperate climate soils.

Details

International Journal of Building Pathology and Adaptation, vol. 41 no. 4
Type: Research Article
ISSN: 2398-4708

Keywords

Article
Publication date: 3 July 2020

Ruben B.O. Acevedo, Klaudia Kantarowska, Edson Costa Santos and Marcio C. Fredel

This paper aims to generate a review of available techniques to measure Residual Stress (RS) in Ti6Al4V components made by Ti6Al4V.

Abstract

Purpose

This paper aims to generate a review of available techniques to measure Residual Stress (RS) in Ti6Al4V components made by Ti6Al4V.

Design/methodology/approach

State of the art; literature review in the field of Residual Stress measurement of Ti6Al4V parts made by selective laser melting (SLM).

Findings

Different Residual Stress measurement techniques were detailed, regarding its concept, advantages and limitations. Regarding all researched references, hole drilling (semi destructive) and X-ray diffraction (nondestructive) were the most cited techniques for Residual Stress measurement of Ti6Al4V parts made by SLM.

Originality/value

An extensive analysis of RS measurement techniques for Ti6Al4V parts made by SLM.

Details

Rapid Prototyping Journal, vol. 29 no. 8
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 5 January 2024

Seyfe Nigussie Adamu, Temesgen Wondimu Aure and Tesfaye Alemu Mohammed

From the factors that affect shear strength of reinforced concrete (RC) beams, the study examines the effect of controversial parameters, width-to-depth (b/d) and effective…

Abstract

Purpose

From the factors that affect shear strength of reinforced concrete (RC) beams, the study examines the effect of controversial parameters, width-to-depth (b/d) and effective length-to-depth (leff/d) ratio on shear strength of RC slender beams.

Design/methodology/approach

The researchers utilized a database of 676 experimental test results from ACI-DAfStb database, Conducted regression analysis to examine relationship between b/d and leff/d ratios and shear strength, compare and analyze sensitivity to changes in b/d and leff/d ratios for the selected 12 shear models for RC beams.

Findings

Increasing b/d ratio enhanced shear strength until b/d ˜ 3, but further increases had limited impact and increasing leff/d ratio resulted in decreased shear strength. From comparative analysis, the models provided by various design standards were found to be safe, with EC-2 and JSCE models being conservative. From considered research models, Campione and Arslan models were conservative, while Kim and White model were observed to be unsafe. Sensitivity analysis indicated ACI318-19, JSCE, CEB-FIP-90 and Arslan models were sensitive to changes in b/d and leff/d ratios. National code models generally captured shear strength characteristics well. Certain models suggested a constant/decreasing b/d effect despite observed shear strength enhancement. Most models indicated improved shear strength with an increasing leff/d ratio, contrary to experimental findings while TS500 and Hwang models aligned with experimental results.

Research limitations/implications

The study's limitations include the dependence on the available database, which may not encompass all possible experimental scenarios. Further research should aim to expand the database and investigate additional parameters that may influence shear strength in RC beams.

Practical implications

The findings of this study have practical implications for the design and analysis of RC beams by suggesting that the width-to-depth and length-to-depth ratios should be carefully considered to optimize shear strength. The identified models can assist engineers in selecting appropriate shear strength prediction models based on specific design scenarios.

Social implications

The study contributes to the advancement of knowledge in the field of reinforced concrete beam design, which has implications for the safety and reliability of structural systems. By understanding the factors influencing shear strength, engineers can design more efficient and robust structures, ensuring the safety of buildings and infrastructure.

Originality/value

This study provides valuable insights into the influence of the width-to-depth and effective length-to-depth ratios on shear strength in reinforced concrete beams. It contributes to the understanding of these factors and their impact on shear strength, addressing the lack of consensus among researchers. The comparative analysis of shear models and the sensitivity analyses add value by identifying the models that align better with experimental observations. The study emphasizes the need for accurate models that account for these factors and highlights the importance of further research to refine and develop improved predictive models.

Details

Multidiscipline Modeling in Materials and Structures, vol. 20 no. 1
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 26 April 2022

Michela Serrecchia

The aim of this study is to examine the trend over time of the demand for .it domain names.This study first assesses whether there is a phase of growth and expansion or at a point…

Abstract

Purpose

The aim of this study is to examine the trend over time of the demand for .it domain names.This study first assesses whether there is a phase of growth and expansion or at a point of saturation. Second, this research can be useful also to compare researches that have considered other internet metrics and other models.

Design/methodology/approach

This paper describes the forecasting methods used to analyze the internet diffusion in Italy. The domain names under the country code top-level domain “.it” have used as metrics. To predict domain names .it the seasonal auto regressive integrated moving average (SARIMA) model and the Holt-Winters (H-W) methods have been used.

Findings

The results show that, to predict domain names .it the SARIMA model is better than the H-W methods. According to the findings, notwithstanding the forecast of a growth in domain names, the increase is however limited (about 3%), tending to reach a phase of saturation of the market of domain names .it.

Originality/value

In general many authors have studied internet diffusion applying statistical models that follow an S-shaped behavior. On the other hand, the more used diffusion models that follow an S-shape not always provide an adequate description of the Internet growth pattern. To achieve this goal, this paper demonstrates how the time series models, in particular SARIMA model and H-W models, fit well in explaining the spread of the internet.

Article
Publication date: 3 August 2023

Pablo Contreras-Contreras, Pedro Cuesta-Valiño and Pablo Gutiérrez-Rodríguez

This study aims to analyze the relationship between expectations of change after a crisis, such as that generated by COVID-19, people's levels of happiness and the propensity for…

Abstract

Purpose

This study aims to analyze the relationship between expectations of change after a crisis, such as that generated by COVID-19, people's levels of happiness and the propensity for pro-sustainable behavior.

Design/methodology/approach

Surveys were conducted using 1,130 observations. The aim was to measure expectations of change during the pandemic. Furthermore, the relationship between these expectations, happiness levels, and attitudes towards sustainability was analyzed for various elements of daily life. Statistical techniques such as principal component analysis (PCA), cluster analysis, variance analysis and correlation analysis were utilized to explore the underlying patterns and relationships.

Findings

Optimistic expectations for post-pandemic change are associated with a greater likelihood of engaging in environmentally beneficial behaviors, leading to higher levels of life satisfaction. This correlation is particularly significant when individuals envision broader transformations in the collective behavior of humanity. These findings suggest a strong link between beliefs in positive societal transformations and both pro-environmental actions and personal well-being.

Research limitations/implications

The unique circumstances of the pandemic, characterized by heightened media consumption, likely influenced the expectations of individuals, particularly fostering pessimistic outlooks in critical situations. Clear and solid variables were utilized despite not employing validated scales to measure expectations. However, it has been proven that there is a clear link between change expectations, happiness, and the propensity for a more sustainable daily life.

Practical implications

This study identifies guidelines that strengthen brands' communication strategies based on individuals' sustainability profiles and visions of the future.

Social implications

There is a need to target skeptical, change-resistant segments of the population with a more convincing and solid discourse to promote sustainable consumption and behavior.

Originality/value

This is the first study to simultaneously address the relationship between individuals' expectations of change following traumatic events such as the pandemic, their engagement in sustainable behavior, and their increased levels of happiness.

Details

Journal of Management Development, vol. 42 no. 6
Type: Research Article
ISSN: 0262-1711

Keywords

Open Access
Article
Publication date: 13 February 2024

Seungjae Shin

The purpose of this study is to compare the competition and productivity of the US freight rail transportation industry for the past 41 years (1980 ∼ 2020), which consists of the…

139

Abstract

Purpose

The purpose of this study is to compare the competition and productivity of the US freight rail transportation industry for the past 41 years (1980 ∼ 2020), which consists of the two periods, before and after the abolishment of the Interstate Commerce Commission (ICC) in 1995.

Design/methodology/approach

This study investigates any relationships between the market concentration index values and labor productivity values in the separate two periods, and how the existence of a regulatory body in the freight transportation market impacted the productivity of the freight rail transportation industry by using a Cobb–Douglas production function on annual financial statement data from the US stock exchange market.

Findings

This study found that, after the abolishment of the ICC: (1) the rail industry became less competitive, (2) even if the rail industry had an increasing labor productivity trend, there was a strong negative correlation between the market concentration index and labor productivity and (3) the rail industry’s total factor productivity was decreased.

Originality/value

This study is to find empirical evidence of the effect of the ICC abolishment on the competition and productivity levels in the US freight rail transportation industry using a continuous data set of 41-year financial statements, which is unique compared to previous studies.

Details

Journal of International Logistics and Trade, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1738-2122

Keywords

Article
Publication date: 25 May 2023

Xuebing Dong, Hong Liu, Nannan Xi, Junyun Liao and Zhi Yang

This study explores whether and how four main factors of short-branded video content (content matching, information relevance, storytelling and emotionality) facilitate consumer…

2923

Abstract

Purpose

This study explores whether and how four main factors of short-branded video content (content matching, information relevance, storytelling and emotionality) facilitate consumer engagement (likes, comments and shares), as well as the moderating effect of the release time (morning, afternoon and evening) in such relationships.

Design/methodology/approach

This study uses Python to write programs to crawl relevant data information, such as consumer engagement and short video release time. It combines coding methods to empirically analyze the impact of short-branded video content characteristics on consumer engagement. A total of 10,240 Weibo short videos (total duration: 238.645 h) from 122 well-known brands are utilized as research objects.

Findings

Empirical results show that the content characteristics of short videos significantly affected consumer engagement. Furthermore, the release time of videos significantly moderated the relationship between the emotionality of short videos and consumer engagement. Content released in the morning enhanced the positive impact of warmth, excitement and joy on consumer engagement, compared to that released in the afternoon.

Practical implications

The findings provide new insights for the dissemination of products and brand culture through short videos. The authors suggest that enterprises that use brand videos consider content matching, information relevance, storytelling and emotionality in their design.

Originality/value

From a broader perspective, this study constructs a new method for comprehensively evaluating short-branded video content, based on four dimensions (content matching, information relevance, storytelling and emotionality) and explores the value of these dimensions for creating social media marketing success, such as via consumer engagement.

Details

Internet Research, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1066-2243

Keywords

Article
Publication date: 26 December 2022

Lakshman Sondhi, Rakesh Kumar Sahu, Shubhankar Bhowmick and Royal Madan

The purpose of this study was to perform thermo-mechanical deformation and stress analysis in a functionally graded (FG) hollow cylinder considering steady-state temperature…

Abstract

Purpose

The purpose of this study was to perform thermo-mechanical deformation and stress analysis in a functionally graded (FG) hollow cylinder considering steady-state temperature distribution under the effect of rotation, gravity and constant heat generation.

Design/methodology/approach

Navier's equation was used to solve the problem, and the obtained results were validated with benchmarks found to be in excellent agreement. The variation of temperature and other material properties such as Young's modulus, density, thermal expansion coefficient and thermal conductivity varied radially as per power-law variation.

Findings

The effect of rotation was found to be vital compared to gravity and heat generation when compared individually and in combination. The results of displacement and stresses were presented for varying grading indices.

Practical implications

FG cylinders have huge industrial applications as it opens the possibility of developing structures with a high strength/weight ratio. The present study will benefit industries in identifying the effective grading index that can be used by industries for fabricating FG structures.

Originality/value

The effect of rotation, body force and heat generation on a cylindrical body has not been studied before. Furthermore, the combined effect of rotation, body force and heat generation has been studied to understand the behaviour of cylinders operating under similar conditions.

Details

International Journal of Structural Integrity, vol. 14 no. 2
Type: Research Article
ISSN: 1757-9864

Keywords

Article
Publication date: 3 November 2021

Nahid Izadpanah Mehrkish and Susan B. Grant

Researchers have long been interested in how the psychology of senior managers affects their behaviours. This paper aims to present the results of a questionnaire into how…

1029

Abstract

Purpose

Researchers have long been interested in how the psychology of senior managers affects their behaviours. This paper aims to present the results of a questionnaire into how positive self-image influences how well senior managers in UK manufacturing organisations support the implementation of management information system (MIS). This study developed two scales, one to measure senior managers’ attitudes and the other to measure support of MIS implementation. It also sought to investigate the impact of senior managers’ positive self-image on their support of MIS implementation in UK manufacturing organisations.

Design/methodology/approach

The authors tested the hypotheses on a data set of 400 senior managers from UK manufacturing organisations. Two unidimensional scales to measure senior managers’ attitude and support level towards MIS implementation were developed. Exploratory factor analysis (EFA) was used to validate the scales. The study also examined the impact of senior managers’ positive self-image on their attitude and support from the perspective of UK manufacturing organisations by using structural equation modelling.

Findings

The study found that senior managers’ positive self-image is a significant contributing factor to their attitude. Also, senior managers’ attitude has a strong positive impact on their support in the MIS implementation process. A strong mediating relationship was found to exist between senior managers’ positive self-image and support through their attitude towards MIS implementation.

Originality/value

Although past literature has examined the importance of senior managers’ attitude and support in successful MIS implementation, there has been no specific scale around management support and attitude towards MIS implementation developed to date. Thus, a contribution of this study is its development of two new scales based on a survey of senior managers of UK manufacturing organisations. The scales can be used to evaluate senior managers’ perception towards MIS implementation and the support they are willing to give whilst implementing MIS. Another contribution of this study is the analysis of positive self-image via item-parcelling which improves model efficiency and provides more stable estimates of the construct.

Details

VINE Journal of Information and Knowledge Management Systems, vol. 53 no. 4
Type: Research Article
ISSN: 2059-5891

Keywords

1 – 10 of over 4000