U. Heck, U. Fritsching and K. Bauckhage
Heat treatment by quenching of individual metallic parts with multiple impinging gas jets is an environmentally friendly alternative to conventional surface hardening and…
Abstract
Heat treatment by quenching of individual metallic parts with multiple impinging gas jets is an environmentally friendly alternative to conventional surface hardening and quenching in liquids. In the present investigation the gas flow field and simultaneous heat transfer process in gas quenching is studied by numerical simulation for surface treatment of a cylindrical sample geometry. Aim of the investigation is the evaluation of optimized flow conditions and nozzle arrangements to achieve: a maximum overall heat release (high integral heat transfer rates) to maximize the quenching efficiency; a local smooth distribution of the cooling process (spatially homogeneous heat transfer) for avoidance of spatial hardness variations. These aims are achieved by derivation of an optimized nozzle arrangement and appropriate operation conditions of the gas jet array with respect to the three dimensional sample geometry of a cylinder to be quenched.
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The paper aims to explore, using an analysis of the three components of memes content, form and stance – whether and how the memes offer a broad picture of a specific society…
Abstract
Purpose
The paper aims to explore, using an analysis of the three components of memes content, form and stance – whether and how the memes offer a broad picture of a specific society during the COVID-19 pandemic crisis.
Design/methodology/approach
The author collected, from the two largest Facebook groups in Israel, 25 memes with the largest number of likes in each month, beginning from the month in which awareness of COVID-19 increased significantly, between March 2020 and February 2019. A total of 597 memes were collected. The data were analyzed by a quantitative and qualitative analysis.
Findings
Findings indicate that meme culture effectively reflects a society’s situation and the challenges it faces. Memes also reflect local cultural icons and effects. Meme contents vary across groups. During a crisis, memes do not function as fertile groups for sharp criticism or calls to take action to resolve society’s social ills.
Practical implications
Memes may serve as a tool to understand and explore an unfamiliar, foreign culture, its state of mind and its history through meme culture.
Social implications
Memes may constitute a platform for relieving stress through light-hearted humor, unaccompanied by a true call to action; that is, “slacktivism” which gives a sense of active participation without involvement in actual activities for change.
Originality/value
The study reveals that the Israeli meme culture is not activist and rather focuses on humor to relieve stress. Memes may be used as “bread and circuses” or a means of “slacktivism” that fails to call to genuine activism.
Peer review
The peer review history for this article is available at: https://publons.com/publon/10.1108/OIR-07-2022-0381
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E. Vishnuvardhanarao and Manab Kumar Das
The purpose of this paper is to consider the conjugate heat transfer from a flat plate involving a turbulent plane wall jet. The bottom wall of the solid block is heated by a…
Abstract
Purpose
The purpose of this paper is to consider the conjugate heat transfer from a flat plate involving a turbulent plane wall jet. The bottom wall of the solid block is heated by a constant heat flux.
Design/methodology/approach
High Reynolds number two‐equation model (κ‐ϵ) has been used for turbulence modeling. The parameters considered are the conductivity ratio of solid and fluid, the solid slab thickness and the Prandtl number. The Reynolds number considered is 15,000 because the flow becomes fully turbulent and then is independent of the Reynolds number. The range of parameters considered are: conductivity ratio = 1‐1,000, solid slab thickness = 1‐10 and Prandtl number = 0.01‐100.
Findings
The non‐dimensional bottom surface temperature is high for high‐Prandtl number fluid and vice versa. As conductivity ratio increases, it decreases whereas it increases with the increase in slab thickness. Similar trend is observed for the distribution of the interface temperature. The Nusselt number computed based on the interface temperature increases with Prandtl number. It is observed that for the range of parameters considered, local Nusselt number distribution superimposes with each other. The average heat flux at the interface has been computed and found to be equal with average heat flux at the bottom which ensures the overall heat balance.
Originality/value
The study of conjugate heat transfer with a turbulent wall jet will be useful for cooling of heated body.
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Ruei-Yan Wu, Ya-Han Hu and En-Yi Chou
Although prior research has employed various variables to predict player churn, the dynamic evolution of the behavioral patterns of players has received limited attention. In this…
Abstract
Purpose
Although prior research has employed various variables to predict player churn, the dynamic evolution of the behavioral patterns of players has received limited attention. In this study, churn prediction models are developed by incorporating the progress level, in-game purchase, social interaction, behavioral pattern and behavioral variability (BV) of players in social casino games (SCGs). The study distinguishes churn prediction between two player groups: monetizers and non-monetizers.
Design/methodology/approach
This study employs three machine learning techniques—logistic regression, decision trees and random forests—using real-world player data from an SCG company to construct churn prediction models. Two experiments were conducted. In Experiment 1, BV was combined with four other variable categories to effectively predict churn behaviors across all players (n = 52,246). In Experiment 2, churn prediction models were developed separately for monetizers (n = 16,628) and non-monetizers (n = 35,618).
Findings
The findings from Experiment 1 indicate that incorporating BV significantly improves the overall performance of churn prediction models. Experiment 2 demonstrates that churn prediction models achieve better performance and predictive accuracy for monetizers and non-monetizers when BV is calculated over the 3-day to 7-day and 7-day to 14-day windows, respectively.
Originality/value
This study introduces BV as a novel variable category for churn prediction, emphasizing within-person variability and demonstrating its effectiveness in enhancing model performance. Churn prediction models were independently constructed for monetizers and non-monetizers, utilizing different time windows for variable extraction. This approach improves predictive performance and highlights key differences in critical variables influencing churn across the two player groups. The findings provide valuable insights into churn management strategies tailored for monetizers and non-monetizers.
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The paper's aim is to provide information on heat transfer and flow characteristics for a jet emerging from a conical nozzle and impinging onto the cylindrical, which resembles…
Abstract
Purpose
The paper's aim is to provide information on heat transfer and flow characteristics for a jet emerging from a conical nozzle and impinging onto the cylindrical, which resembles the laser heating process, for researchers and graduate students working in the laser processing area, which can help them to improve the understanding of the laser machining process.
Design/methodology/approach
A numerical scheme employing the control volume approach is introduced to model the flow and heating situations. The effect of jet velocity on the heat transfer rates and skin friction around the cylindrical cavity subjected to the jet impingement was investigated.
Findings
Increasing jet velocity at nozzle exit enhances the heat transfer rates from the cavity wall and modifies the skin friction at cavity wall, which is more pronounced as the cavity depth increases to 1 mm.
Research limitations/implications
The effects of nozzle cone angle on the flow structure and heat transfer characteristics were not examined, which perhaps limits the general usefulness of the findings.
Practical implications
Very useful information are provided for the laser gas assisted processing, which has a practical importance in machining industry.
Originality/value
This paper provides original information for the effects of the gas jet velocity on the cooling rates of the laser produced cavity.
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Inna Soifer, Katerina Berezina, Olena Ciftci and Alexander Mafusalov
This study aims to explore virtual site visit adoption patterns of US convention facilities based on the diffusion of innovation (DOI) theory. Additionally, it offers predictive…
Abstract
Purpose
This study aims to explore virtual site visit adoption patterns of US convention facilities based on the diffusion of innovation (DOI) theory. Additionally, it offers predictive models of virtual site visit tool adoption by applying probability distributions.
Design/methodology/approach
The study used content analysis of 369 US convention facility websites. Data collected from the websites recorded the presence or absence of the following tools facilitating virtual site visits: photos, floor plans, videos, 360-photos, 360-tours and virtual reality (VR)-optimized tours. The website content analysis was followed by application of the DOI theory and predictive modeling.
Findings
According to the DOI theory, the use of VR-optimized tours (4.34%) is still in the early adoption stage, followed by 360-degree tours (12.74%) and standard videos (17.89%) that have transitioned into the early majority stage of adoption and photos (72.09%) and floor plans (84.82%) that represent a late majority stage. Three predictive models with shifted Gompertz, Gumbel and Bass distributions forecasted that convention centers would achieve a 50% adoption rate of 360-degree tools (photos and tours) in 4.67, 4.2 and three years, respectively. The same models predicted a 50% adoption rate of 360-degree tours in 6.62, 5.81 and 4.42 years.
Practical implications
The research indicates that most US convention facilities have not taken full advantage of their websites as a sales and marketing tool.
Originality/value
This study is the first comprehensive attempt to evaluate the adoption rate of VR and other technologies enabling virtual site visits by using content analysis of US convention facility websites. Additionally, it is the first attempt to apply probability distributions to predict technology adoption in the convention industry context.
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Pakorn Opasvitayarux, Siri-on Setamanit, Nuttapol Assarut and Krisana Visamitanan
The introduction of quality management Internet of things (QM IoT) can help food supply chain members to enhance real-time visibility, quality, safety and efficiency of products…
Abstract
Purpose
The introduction of quality management Internet of things (QM IoT) can help food supply chain members to enhance real-time visibility, quality, safety and efficiency of products and processes. Current literature indicates three main research gaps, including a lack of studies in QM IoT in the food supply chain, the vagueness of integrative adoption of new technology framework and deficient research covering both adoption attitude and intention in the same model. This study aims to propose an analysis model based on the technological–organizational–environmental (TOE) framework and reinforced by the collaborative structure to capture the importance of the supply chain network.
Design/methodology/approach
The partial least square-structural equation modeling (PLS-SEM) was applied to test the impacts of the adoption factors on QM IoT adoption attitude and intention among 197 respondents in food manufacturing in Thailand.
Findings
The results indicated that compatibility, trialability, adaptive capacity, innovative capability, executive support, value chain partner pressure, presence of service provider and information sharing significantly impacted the attitude toward QM IoT adoption, while adaptive capability, innovative capability and information sharing directly influenced the QM IoT adoption intention. Furthermore, the attitude toward QM IoT adoption positively impacted the QM IoT adoption intention.
Practical implications
This study contributed to academicians by proposing a more solid adoption framework for QM IoT area. In addition, the business practitioners could actively prepare themselves for the QM IoT adoption, whereas the service providers could provide better and suitable service.
Originality/value
This research contributes to the building of a more solid framework and indicates significant factors that impact the attitude toward QM IoT adoption and adoption intention.
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Adarsh Anand, Mohammed Shahid Irshad and Yogesh K. Dwivedi
YouTube allows its users to upload and view videos on its platform. YouTube provides notification to the subscribers whenever a channel uploads a new video thereby making the…
Abstract
Purpose
YouTube allows its users to upload and view videos on its platform. YouTube provides notification to the subscribers whenever a channel uploads a new video thereby making the channel subscribers the potential viewers of the video. And thus, they are the first to come to know about any new offering. But later on, the view count also increases due to virality, that is, mass sharing of the content by the users on different social media platforms similar to word-of-mouth in the field of marketing. Therefore, the purpose of this paper is to examine different diffusion patterns as they can help to inflate traffic and generate revenue.
Design/methodology/approach
YouTube's view count grows majorly through virality. The pattern of view count growth has generally been considered unimodal in most of the available research in the field of YouTube. In the present work, the growth process due to views through the subscribers and views due to word-of-mouth (virality) is presented. Considering that the impact of virality in view count growth comes later in the video life cycle; the viewing patterns of both the segments have been mathematically modeled; independently.
Findings
Different models have been proposed to capture the view count growth pattern and how the impact of virality changes the view count growth curve and thereby results in a multimodal curve structure. The proposed models have been verified on various view count data sets of YouTube videos using SPSS (Statistical Package for the Social Sciences), and their ranks have been determined using a weighted criteria–based approach. The results obtained clearly depict the presence of many modes in the life cycle of view counts.
Originality/value
Till now, the literature is evident of the video life cycle following a bell shape curve. This study claims that the initial thrust is by subscribers and then the contribution in the view count by people watching via word-of-mouth comes into picture and brings in another hump in the growth curve.
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Ahmad Honarjoo, Ehsan Darvishan, Hassan Rezazadeh and Amir Homayoon Kosarieh
This article introduces SigBERT, a novel approach that fine-tunes bidirectional encoder representations from transformers (BERT) for the purpose of distinguishing between intact…
Abstract
Purpose
This article introduces SigBERT, a novel approach that fine-tunes bidirectional encoder representations from transformers (BERT) for the purpose of distinguishing between intact and impaired structures by analyzing vibration signals. Structural health monitoring (SHM) systems are crucial for identifying and locating damage in civil engineering structures. The proposed method aims to improve upon existing methods in terms of cost-effectiveness, accuracy and operational reliability.
Design/methodology/approach
SigBERT employs a fine-tuning process on the BERT model, leveraging its capabilities to effectively analyze time-series data from vibration signals to detect structural damage. This study compares SigBERT's performance with baseline models to demonstrate its superior accuracy and efficiency.
Findings
The experimental results, obtained through the Qatar University grandstand simulator, show that SigBERT outperforms existing models in terms of damage detection accuracy. The method is capable of handling environmental fluctuations and offers high reliability for non-destructive monitoring of structural health. The study mentions the quantifiable results of the study, such as achieving a 99% accuracy rate and an F-1 score of 0.99, to underline the effectiveness of the proposed model.
Originality/value
SigBERT presents a significant advancement in SHM by integrating deep learning with a robust transformer model. The method offers improved performance in both computational efficiency and diagnostic accuracy, making it suitable for real-world operational environments.
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The conventional pedestrian detection algorithms lack in scale sensitivity. The purpose of this paper is to propose a novel algorithm of self-adaptive scale pedestrian detection…
Abstract
Purpose
The conventional pedestrian detection algorithms lack in scale sensitivity. The purpose of this paper is to propose a novel algorithm of self-adaptive scale pedestrian detection, based on deep residual network (DRN), to address such lacks.
Design/methodology/approach
First, the “Edge boxes” algorithm is introduced to extract region of interests from pedestrian images. Then, the extracted bounding boxes are incorporated to different DRNs, one is a large-scale DRN and the other one is the small-scale DRN. The height of the bounding boxes is used to classify the results of pedestrians and to regress the bounding boxes to the entity of the pedestrian. At last, a weighted self-adaptive scale function, which combines the large-scale results and small-scale results, is designed for the final pedestrian detection.
Findings
To validate the effectiveness and feasibility of the proposed algorithm, some comparison experiments have been done on the common pedestrian detection data sets: Caltech, INRIA, ETH and KITTI. Experimental results show that the proposed algorithm is adapted for the various scales of the pedestrians. For the hard detected small-scale pedestrians, the proposed algorithm has improved the accuracy and robustness of detections.
Originality/value
By applying different models to deal with different scales of pedestrians, the proposed algorithm with the weighted calculation function has improved the accuracy and robustness for different scales of pedestrians.