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1 – 10 of over 1000Mohammad Sedigh Kohanpour and Gholamreza Imani
This study aims to investigate lattice Boltzmann (LB) simulation of the fluid flow and heat transfer characteristics of a heated porous elliptic cylinder in uniform flow based on…
Abstract
Purpose
This study aims to investigate lattice Boltzmann (LB) simulation of the fluid flow and heat transfer characteristics of a heated porous elliptic cylinder in uniform flow based on the two-domain scheme. In the present research, the effect of axis ratio (1 ≤ AR ≤ 2), Reynolds number (5 ≤ Re ≤ 40) and Darcy number (10−4 ≤ Da ≤ 10−2) are studied.
Design/methodology/approach
To perform the LB simulation based on the two-domain scheme, the nonequilibrium extrapolation method is modified to model the heat transfer interfacial conditions required at the curved interface.
Findings
The results show that the axis ratio as well as Reynolds and Darcy numbers significantly affect the fluid flow and heat transfer characteristics of the porous elliptic cylinder. It is shown that for AR > 1, the phenomenon of detached recirculating zone occurs at much higher Darcy numbers compared with the case of the porous circular cylinder (AR = 1). The results show that the location of maximum temperature within the cylinder moves downstream when the Reynolds number, Darcy number and axis ratio increase. It is also concluded that the average Nusselt number of a porous elliptic cylinder is always lower than that of a porous circular cylinder.
Originality/value
The LB simulation of forced convection from a porous cylinder in uniform flow with a curved interface based on the two-domain scheme has not been studied yet.
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Gholamreza Imani and Mohsen Mozafari-Shamsi
The lattice Boltzmann simulation of fluid flow in partial porous geometries with curved porous-fluid interfaces has not been investigated yet. It is mainly because of the lack of…
Abstract
Purpose
The lattice Boltzmann simulation of fluid flow in partial porous geometries with curved porous-fluid interfaces has not been investigated yet. It is mainly because of the lack of a method in the lattice Boltzmann framework to model the hydrodynamic compatibility conditions at curved porous-fluid interfaces, which is required for the two-domain approach. Therefore, the purpose of this study is to develop such a method.
Design/methodology/approach
This research extends the non-equilibrium extrapolation lattice Boltzmann method for satisfying no-slip conditions at curved solid boundaries, to model hydrodynamic compatibility conditions at curved porous-fluid interfaces.
Findings
The proposed method is tested against the results available from conventional numerical methods via the problem of fluid flow through and around a porous circular cylinder in crossflow. As such, streamlines, geometrical characteristics of recirculating wakes and drag coefficient are validated for different Reynolds (5 ≤ Re ≤ 40) and Darcy (10−5 ≤ Da ≤ 5 × 10−1) numbers. It is also shown that without applying any compatibility conditions at the interface, the predicted flow structure is not satisfactory, even for a very fine mesh. This result highlights the importance of the two-domain approach for lattice Boltzmann simulation of the fluid flow in partial porous geometries with curved porous-fluid interfaces.
Originality/value
No research is found in the literature for applying the hydrodynamic compatibility conditions at curved porous-fluid interfaces in the lattice Boltzmann framework.
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Dominique Gobin and Benoit Goyeau
This paper aims to provide a limited, but selective bibliography on modelling heat and mass transfer in composite fluid‐porous domains.
Abstract
Purpose
This paper aims to provide a limited, but selective bibliography on modelling heat and mass transfer in composite fluid‐porous domains.
Design/methodology/approach
Since the pioneer study by Beavers and Joseph, the problem of interface continuity and/or jump conditions at a fluid‐porous interface has been of interest to the fluid mechanics and heat and mass transfer community. The paper is concerned both with numerical simulations of heat and fluid flow in such systems, and with the linear stability problems.
Findings
The one‐ and two‐domain formulations are equivalent. Using the Darcy‐Brinkman extension instead of the Darcy model reduces the number of ad hoc parameters in this configuration.
Research limitations/implications
The problem of double diffusive convection has still to be solved and analyzed.
Practical implications
The discussion on the interface conditions is of great relevance to many industrial and practical situations.
Originality/value
The important question of the macroscopic formulation of the problem is tackled in the paper.
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I. Raspo, J. Ouazzani and R. Peyret
This paper presents a spectral multidomain method for solving theNavier‐Stokes equations in the vorticity‐stream function formulation. Thealgorithm is based on an extensive use of…
Abstract
This paper presents a spectral multidomain method for solving the Navier‐Stokes equations in the vorticity‐stream function formulation. The algorithm is based on an extensive use of the influence matrix technique and so leads to a direct method without any iterative process. Numerical results concerning the Czochralski melt configuration are reported and compared with spectral monodomain solutions to show the advantage of the domain decomposition for such a problem which solution presents a singular behaviour.
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Hei-Chia Wang, Army Justitia and Ching-Wen Wang
The explosion of data due to the sophistication of information and communication technology makes it simple for prospective tourists to learn about previous hotel guests'…
Abstract
Purpose
The explosion of data due to the sophistication of information and communication technology makes it simple for prospective tourists to learn about previous hotel guests' experiences. They prioritize the rating score when selecting a hotel. However, rating scores are less reliable for suggesting a personalized preference for each aspect, especially when they are in a limited number. This study aims to recommend ratings and personalized preference hotels using cross-domain and aspect-based features.
Design/methodology/approach
We propose an aspect-based cross-domain personalized recommendation (AsCDPR), a novel framework for rating prediction and personalized customer preference recommendations. We incorporate a cross-domain personalized approach and aspect-based features of items from the review text. We extracted aspect-based feature vectors from two domains using bidirectional long short-term memory and then mapped them by a multilayer perceptron (MLP). The cross-domain recommendation module trains MLP to analyze sentiment and predict item ratings and the polarities of the aspect based on user preferences.
Findings
Expanded by its synonyms, aspect-based features significantly improve the performance of sentiment analysis on accuracy and the F1-score matrix. With relatively low mean absolute error and root mean square error values, AsCDPR outperforms matrix factorization, collaborative matrix factorization, EMCDPR and Personalized transfer of user preferences for cross-domain recommendation. These values are 1.3657 and 1.6682, respectively.
Research limitation/implications
This study assists users in recommending hotels based on their priority preferences. Users do not need to read other people's reviews to capture the key aspects of items. This model could enhance system reliability in the hospitality industry by providing personalized recommendations.
Originality/value
This study introduces a new approach that embeds aspect-based features of items in a cross-domain personalized recommendation. AsCDPR predicts ratings and provides recommendations based on priority aspects of each user's preferences.
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David Forbes and Pornpit Wongthongtham
There is an increasing interest in using information and communication technologies to support health services. But the adoption and development of even basic ICT communications…
Abstract
Purpose
There is an increasing interest in using information and communication technologies to support health services. But the adoption and development of even basic ICT communications services in many health services is limited, leaving enormous gaps in the broad understanding of its role in health care delivery. The purpose of this paper is to address a specific (intercultural) area of healthcare communications consumer disadvantage; and it examines the potential for ICT exploitation through the lens of a conceptual framework. The opportunity to pursue a new solutions pathway has been amplified in recent times through the development of computer-based ontologies and the resultant knowledge from ontologist activity and consequential research publishing.
Design/methodology/approach
A specific intercultural area of patient disadvantage arises from variations in meaning and understanding of patient and clinician words, phrases and non-verbal expression. Collection and localization of data concepts, their attributes and individual instances were gathered from an Aboriginal trainee nurse focus group and from a qualitative gap analysis (QGA) of 130 criteria-selected sources of literature. These concepts, their relationships and semantic interpretations populate the computer ontology. The ontology mapping involves two domains, namely, Aboriginal English (AE) and Type II diabetes care guidelines. This is preparatory to development of the Patient Practitioner Assistive Communications (PPAC) system for Aboriginal rural and remote patient primary care.
Findings
The combined QGA and focus group output reported has served to illustrate the call for three important drivers of change. First, there is no evidence to contradict the hypothesis that patient-practitioner interview encounters for many Australian Aboriginal patients and wellbeing outcomes are unsatisfactory at best. Second, there is a potent need for cultural competence knowledge and practice uptake on the part of health care providers; and third, the key contributory component to determine success or failures within healthcare for ethnic minorities is communication. Communication, however, can only be of value in health care if in practice it supports shared cognition; and mutual cognition is rarely achievable when biopsychosocial and other cultural worldview differences go unchallenged.
Research limitations/implications
There has been no direct engagement with remote Aboriginal communities in this work to date. The authors have initially been able to rely upon a cohort of both Indigenous and non-Indigenous people with relevant cultural expertise and extended family relationships. Among these advisers are health care practitioners, academics, trainers, Aboriginal education researchers and workshop attendees. It must therefore be acknowledged that as is the case with the QGA, the majority of the concept data is from third parties. The authors have also discovered that urban influences and cultural sensitivities tend to reduce the extent of, and opportunity to, witness AE usage, thereby limiting the ability to capture more examples of code-switching. Although the PPAC system concept is qualitatively well developed, pending future work planned for rural and remote community engagement the authors presently regard the work as mostly allied to a hypothesis on ontology-driven communications. The concept data population of the AE home talk/health talk ontology has not yet reached a quantitative critical mass to justify application design model engineering and real-world testing.
Originality/value
Computer ontologies avail us of the opportunity to use assistive communications technology applications as a dynamic support system to elevate the pragmatic experience of health care consultations for both patients and practitioners. The human-machine interactive development and use of such applications is required just to keep pace with increasing demand for healthcare and the growing health knowledge transfer environment. In an age when the worldwide web, communications devices and social media avail us of opportunities to confront the barriers described the authors have begun the first construction of a merged schema for two domains that already have a seemingly intractable negative connection. Through the ontology discipline of building syntactically and semantically robust and accessible concepts; explicit conceptual relationships; and annotative context-oriented guidance; the authors are working towards addressing health literacy and wellbeing outcome deficiencies of benefit to the broader communities of disadvantage patients.
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Leonello Trivelli, Andrea Apicella, Filippo Chiarello, Roberto Rana, Gualtiero Fantoni and Angela Tarabella
Circumstances that are have a significant impact on it. In particular, environmental sustainability related to the increase of worldwide population, and market demand for…
Abstract
Purpose
Circumstances that are have a significant impact on it. In particular, environmental sustainability related to the increase of worldwide population, and market demand for agricultural products (with consumers more and more aware about cultivation and breeding techniques and interested in healthy and high-quality products) represent two of the key challenges that the agricultural sector is going to face in next years. In such a landscape, technological innovations that can support organizations and entrepreneurs to face these problems become increasingly important, and Industry 4.0 is the most striking example. Indeed, the Industry 4.0 paradigm aims to integrate digital technologies into business processes to raise productivity levels and to develop new business models. Accordingly, digital technologies play a similar role in the precision agriculture domain, and the purpose of this paper is to understand if the technologies at the basis of these two paradigms are the same or not.
Design/methodology/approach
The present work investigates how the two domains of Industry 4.0 and precision agriculture are connected to one another by analyzing the most used technologies in both the fields in order to highlight common patterns and technological overlaps. To reach such goal, an approach combining manual and automated analysis was developed.
Findings
The research work generated three main results: a dictionary of precision agriculture technologies including 324 terms; a graph, describing the connections between the technologies composing the dictionary; and a representation of the main technological clusters identified.
Originality/value
These show how the two domains under analysis are directly connected and describe the most important technologies to leverage when approaching digital transformation processes in the agricultural sector.
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The purpose of this study is to investigate the value of cloud computing adoption (CCA) as a proxy for information technology (IT) flexibility (ITF) and IT effectiveness (ITE…
Abstract
Purpose
The purpose of this study is to investigate the value of cloud computing adoption (CCA) as a proxy for information technology (IT) flexibility (ITF) and IT effectiveness (ITE) among Small- and medium-sized enterprises (SMEs) in Jordan.
Design/methodology/approach
A research framework with five hypotheses has been developed based on the results of previous studies. Partial least squares-structural equation modeling has been used for data analysis.
Findings
The results revealed that elements of ITF in two domains, IT technical resource (connectivity, modularityand compatibility) and IT human resource (IT personnel skills) specific to CCA, were significantly correlated with ITE.
Research limitations/implications
The findings have crucial implications: they contribute to the research community, administrators and cloud computing providers (CSPs) concerning the framework-improved procedure for CCA. The proposed model can enhance the awareness of service providers about why some SMEs accept cloud computing services, whereas actually the same ones having the same type of business do not. In addition, the above providers should enhance their interaction with the SMEs that contributed to the cloud computing knowledge to make a well-organized setting for the CCA, specifically, SMEs need that adopt an on-premise private cloud architecture. Moreover, necessary to determine the challenges in deploying solutions from the perspective of CSPs. The sample has been limited to Jordan respondents.
Practical implications
The research studies about the usage of cloud computing have shown its effects on SMEs today. Also, the different impacts of cloud computing on other sectors are at the center of attention. SMEs could get significant advantages by carefully considering and managing CCA from the ITF and ITE perspective.
Originality/value
To the best of the author’s knowledge, this is the first study to develop a framework for CCA based on the standpoint of ITF in two domains, IT technical resources (connectivity, modularity and compatibility) and IT human resources (IT personnel skills) and effectiveness.
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Xinzhi Cao, Yinsai Guo, Wenbin Yang, Xiangfeng Luo and Shaorong Xie
Unsupervised domain adaptation object detection not only mitigates model terrible performance resulting from domain gap, but also has the ability to apply knowledge trained on a…
Abstract
Purpose
Unsupervised domain adaptation object detection not only mitigates model terrible performance resulting from domain gap, but also has the ability to apply knowledge trained on a definite domain to a distinct domain. However, aligning the whole feature may confuse the object and background information, making it challenging to extract discriminative features. This paper aims to propose an improved approach which is called intrinsic feature extraction domain adaptation (IFEDA) to extract discriminative features effectively.
Design/methodology/approach
IFEDA consists of the intrinsic feature extraction (IFE) module and object consistency constraint (OCC). The IFE module, designed on the instance level, mainly solves the issue of the difficult extraction of discriminative object features. Specifically, the discriminative region of the objects can be paid more attention to. Meanwhile, the OCC is deployed to determine whether category prediction in the target domain brings into correspondence with it in the source domain.
Findings
Experimental results demonstrate the validity of our approach and achieve good outcomes on challenging data sets.
Research limitations/implications
Limitations to this research are that only one target domain is applied, and it may change the ability of model generalization when the problem of insufficient data sets or unseen domain appeared.
Originality/value
This paper solves the issue of critical information defects by tackling the difficulty of extracting discriminative features. And the categories in both domains are compelled to be consistent for better object detection.
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Henrik Saabye, Daryl John Powell and Paul Coughlan
Being acquainted with both lean and action learning in theory and in practice, this study finds that the theoretical complementarity of these two research streams has…
Abstract
Purpose
Being acquainted with both lean and action learning in theory and in practice, this study finds that the theoretical complementarity of these two research streams has traditionally been underexploited. In this conceptual paper, this study aims to advance the theoretical understanding of lean by exploring the complementarity of lean thinking and action learning leading to a proposed integrated theory of these two research streams. Target audience is the operations management research community.
Design/methodology/approach
By deliberately adopting a process of theorising, this paper explores, reflects upon and combines individual experiences of researching, teaching and engaging in lean and action learning as operations management scholars.
Findings
Having taken a gemba walk through the literature and practices of lean and action learning, this study views and notices a systematic and complementary relationship between the two domains. The overlapping theoretical and practical complementarities of lean and action learning suggest that these two research streams are ripe for synthesis into an integrated theory. This finding provides an opportunity to (1) progress towards an integrative design of interventions leading to more sustainable lean system adoptions and (2) add new depth to our theoretical explanation of the success and failures of lean system adoptions.
Originality/value
This paper contributes an original integrated theory perspective on lean and action learning.
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