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The purpose of this paper is to understand a flameproof distance necessary to avoid the flame harms to underground personnel which may have great significance to the safety of underground personnel and the disaster relief of gas explosions in coal mines.

Through a roadway with a length of 100 m and a cross-section area of 80 mm×80 mm, the flame propagation of premixed methane-air deflagrations were simulated by using AutoReaGas software for various fuel concentrations (7, 8, 9.5, 11, and 14 percent), fuel volumes (0.0128, 0.0384, 0.064, and 0.0896 m3), initial temperatures (248, 268, 288, 308, and 328 K), and initial pressures (20, 60, 101.3, 150, and 200 kPa).

The maximum combustion rate for each point follows a changing trend of increasing and decreasing with the distance increasing from the ignition source, and it increases with the fuel volume increasing or the initial pressure increasing, and decreases with the initial temperature increasing. However, increasing the initial temperature increases the flame arrival time for each point. The flameproof distance follows a changing trend of increasing and decreasing with the fuel concentration increasing, and it linearly increases with the fuel volume increasing or the initial temperature increasing. However, the flameproof distances are all 17 m for various initial pressures.

Increasing initial temperature increases flame arrival time for each test point. Flameproof distance increases and then decreases with fuel concentration increasing. Increasing fuel volume or initial temperature linearly increases flameproof distance. Initial pressure has little impact on the flameproof distance.

The purpose of this paper is to develop a three‐dimensional (3D) numerical model capable of predicting the vaporization rate of a liquid fuel droplet exposed to a convective turbulent airflow at ambient room temperature and atmospheric pressure conditions.

The 3D Reynolds‐Averaged Navier‐Stokes equations, together with the mass, species, and energy conservation equations were solved in Cartesian coordinates. Closure for the turbulence stress terms for turbulent flow was accomplished by testing two different turbulence closure models; the low‐Reynolds number (LRN) k‐ε and shear‐stress transport (SST). Numerical solution of the resulted set of equations was achieved by using blocked‐off technique with finite volume method.

The present predictions showed good agreement with published turbulent experimental data when using the SST turbulence closure model. However, the LRN k‐ε model produced poor predictions. In addition, the simple numerical approach employed in the present code demonstrated its worth.

The present study is limited to ambient room temperature and atmospheric pressure conditions. However, in most practical spray flow applications droplets evaporate under ambient high‐pressure and a hot turbulent environment. Therefore, an extension of this study to evaluate the effects of pressure and temperature will make it more practical.

It is believed that the numerical code developed is of great importance to scientists and engineers working in the field of spray combustion. This paper also demonstrated for the first time that the simple blocked‐off technique can be successfully used for treating a droplet in the flow calculation domain.

Highly anisotropic zirconium is a material used in the cladding of nuclear fuel rods, ensuring containment of the radioactive material within. The complex material structure of anisotropic zirconium requires model developers to replicate not only the macro-scale stresses but also the meso-scale material behavior as the crystal structure evolves; leading to strongly coupled multi-scale plasticity models. Such strongly coupled models can be achieved through partitioned analysis techniques, which couple independently developed constituent models through an iterative exchange of inputs and outputs. Throughout this iterative process, biases, and uncertainties inherent within constituent model predictions are inevitably transferred between constituents either compensating for each other or accumulating during iterations. The paper aims to discuss these issues.

A finite element model at the macro-scale is coupled in an iterative manner with a meso-scale viscoplastic self-consistent model, where the former supplies the stress input and latter represents the changing material properties. The authors present a systematic framework for experiment-based validation taking advantage of both separate-effect experiments conducted within each constituent’s domain to calibrate the constituents in their respective scales and integral-effect experiments executed within the coupled domain to test the validity of the coupled system.

This framework developed is shown to improve predictive capability of a multi-scale plasticity model of highly anisotropic zirconium.

For multi-scale models to be implemented to support high-consequence decisions, such as the containment of radioactive material, this transfer of biases and uncertainties must be evaluated to ensure accuracy of the predictions of the coupled model. This framework takes advantage of the transparency of partitioned analysis to reduce the accumulation of errors and uncertainties.

The great magnitude differences between the integral tunnel and its structure details make it impossible to numerically model and analyze the global and local seismic behavior of large-scale shield tunnels using a unified spatial scale, even with the help of supercomputers. The paper aims to present a combined equivalent & multi-scale simulation method, by which the tunnel's major mechanical properties under seismic loads can be represented by the equivalent model, and the seismic responses of the interested details can be studied efficiently by the coupled multi-scale model.

The nominal orthotropic material constants of the equivalent tunnel model are inversely determined by fitting the modal characteristics of the equivalent model with the corresponding segmental lining model. The critical sections are selected by comprehensive analyzing of the integral compression/extension and bending loads in the equivalent lining under the seismic shaking and the coupled multi-scale model containing the details of interest is solved by the mixed time explicit integration algorithm.

The combined equivalent & multi-scale simulation method is an effective and efficient way for seismic analyses of large-scale tunnels. The response of each flexible joint is related to its polar location on the lining ring, and the mixed time integration method can speed-up the calculation process for hybrid FE model with great differences in element sizes.

The orthotropic equivalent assumption is, to the best of the authors’ knowledge, for the first time, used in the 3D simulation of the shield tunnel lining, representing the rigidity discrepancies caused by the structural property.

The purpose of this paper is to explore how global operations of manufacturing companies influence the choice of product architecture decisions, ranging from integral to modular product designs.

The authors perform a multiple-case study of three global manufacturing companies with integral and modular product architectures.

The authors find that the internal network capabilities, the number of capable plants, the focus of component plants, the focus of assembly plants, the distances from key suppliers to internal plants, and the number of market segments significantly influence the choice of integral vs modular architecture.

This study is limited to three large manufacturing companies with global operations. However, the authors investigate both integral and modular products. The authors develop propositions that can be tested in further survey research.

The findings show that the type of global operations network influences the decision on product architecture, such that certain global operations characteristics support integral product designs, while other characteristics support modular designs.

To the best of the authors’ knowledge this paper is the first study on the explicit impact of global operations on product architecture, rather than the other way around.

The purpose of this paper is to explore how integral and modular product architectures influence the design properties of the global operations network.

The authors perform a multiple-case study of three global manufacturing companies, using interviews, seminars and structured questionnaires to identify ideal design properties.

The authors find that the choice of integral vs modular product architecture lead to significant differences in the preferred design properties of global operations networks concerning number of key technologies in-house, number of capable plants, focus at assembly plants, distance between assembly plant and market, and number of key supplier sites. Two of these were identified through this research, i.e. the number of capable plants and number of key supplier sites. The authors make a distinction between component and assembly plants, which adds detail to the understanding of the impact of product architecture on global operations. In addition, they develop five propositions that can be tested in further survey research.

This study is restricted to three large manufacturing companies with global operations. However, the authors investigated both integral and modular products at these three companies and their associated global operations network. Still, further case or survey research involving a broader set of companies is warranted.

The key aspects for integral products are to have many key technologies in-house, concentration of production at a few capable plants, and economies-of-scale at assembly plants, while long distances between assembly plants and markets as well as few key supplier sites are acceptable. For modular products, the key aspects are many capable plants, economies-of-scope at assembly plants, short distance between assembly plants and markets, and many key supplier sites, while key technologies do not necessarily have to reside in-house – these can be accessed via key suppliers.

This paper is, to the authors’ knowledge, the first study on the explicit impact of product architecture on global operations networks, especially considering the internal manufacturing network.

E-commerce, with technology as its backbone, is an indispensable business trend associated with the wave of the Fourth Industrial Revolution. Recently, its intensifying role has also been noticed due to the COVID-19 pandemic. However, technology adoption to pursue an e-commerce model for agribusinessmen is not easy, while the COVID-19 has made them lose customers and led them to crises. In that context, the role of social capital (SC) has increasingly been paid significant attention, especially for micro and family businesses. Agribusinessmen can use SC to adopt technology, renew and reinforce their businesses in the global agricultural supply chain disruption context. However, there seems to be a dearth of an integral measurement of social capital (IMSC) to apply to the practice effectively. Recognizing this need, the current study aims to develop an integral scale for SC.

This research adopts a widely accepted and rigorous scale development process, a mixed-methods research design and essential statistical techniques to develop an IMSC.

The result develops an IMSC consisting of nine facets: linking-corporate, bonding-bridging, trust in political institutions, trust in public services, generalized social trust, norms and social sanctions, subjective safety, civicness and community cohesiveness. The scales of these facets are found to be unidimensional, reliable and valid.

This is the first study developing an IMSC to contribute to the extant literature. The study also provides managerial implications for practitioners to strengthen SC and adopt technology to improve their businesses.

Leadership and management skills are increasingly required to navigate organisations through the complexities and changes of contemporary environments. Over the last decade, 3608 feedback is a process that has gained wide usage to help development of these skills. Summarises current research on 3608 feedback and the development of an integrated model of leadership and management based on the theories of Wilber. The article describes a comprehensive “integral” model and a questionnaire that uses elements of 3608 feedback to measure roles of leadership and management, as well as dimensions of self‐development and strategic change skills. This approach is applied to a sample of 304 managers and over 1,000 subordinates. The construction, validity and results of the questionnaire are discussed, as well as the major leadership strengths and weaknesses of the sample managers. Issues and experiences in the use of this model and the 3608 process are described.

The education services sector faces ever-changing global market dynamics with creative disruptions. Building knowledge brands can push the higher education sector beyond its geographical boundaries into the global arena. This study aims to identify key constructs, their theoretical background and dimensions that aid in building a global knowledge brand. The authors' research focuses on adapting and validating scales for global knowledge and education services brands from well-established academic literature.

The authors have adopted a mixed methodology approach and a systematic literature review. Authors interviewed 18 subject matter experts as part of content and face validity to arrive at select constructs, dimensions and items. Quantitative methods with random sampling were adopted as the primary methodology. Initially, the survey was administered to 390 students to test preliminary results. The survey was also administered to 5,112 students at a later part of this study. Valid responses stood at 3,244 with a 63% response rate. Further, the authors conducted confirmatory factor analysis, exploratory factor analysis and structural equation modeling to test the reliability and validity of scales. This study analyzed composite reliability, convergent validity and discriminant validity to finalize items for scales. The authors also validated the hypotheses based on the discriminant validity assessment scores.

Authors' key research findings are that academic stimulus, campus infrastructure and student intent play a significant role in campus culture and events design and experience at campus. Authors were able to bring out 16 key constructs and 55 critical dimensions vital to global education services brand building. This study also adapted and validated 99 items that meet construct validity and composite reliability criteria. This study also highlights that constructs such as student intent, academic stimulus, campus infrastructure scalability, selection mechanism, pedagogical content knowledge, brand identity, events experience and campus culture play a vital role in global brand recognition.

The authors' work is fairly generalizable to education services and the higher education sector. However, this study must be extrapolated and empirically validated in other industry sectors. The research implications of this study are that it aided the authors in building theoretical background for student brand loyalty theory, student expectation theory and study loyalty theory. This study adds to the body of knowledge by contributing to theoretical concepts on students, knowledge culture, events, infrastructure and branding. Researchers can adopt the scales proposed in this study to build research models in higher education branding. This study acts as a catalyst for building theories in education services areas. Researchers can delve deep into proposed research aspects of campus infrastructure, knowledge infrastructure, campus knowledge culture, events design and events experience.

This study aids educators and brand managers to develop global education services and optimize their effort and budget. Administrators in the education services sector must focus on practical aspects of student perception, campus infrastructure, culture and events experience. Practically administrators can reorient their efforts based on this study to achieve global brand recognition.

This study highlights that students are not customers but are co-creators of value in the education sector. This study provides scales and dimensions needed to build co-creation frameworks and models.

Most research in higher education branding has not covered wider aspects of global brand building. Existing theories proposed in higher education and education services articles cover only narrower aspects of campus infrastructure, culture, events design and branding. This study presents a comprehensive list of critical factors that play a vital role in global knowledge brand building. This study highlights the constructs and scales integral to building a global education services brand.

The purpose of this paper is to discuss some fundamental aspects regarding the anomalies in the passive scalar field advected by forced homogenous and isotropic turbulence, by inspection of the analytical properties of the governing equations and with the aid of direct numerical simulation (DNS) data.

Results from a pseudo‐spectral DNS of a unitary‐Schmidt‐ number passive scalar advected by a low Reynolds number flow field, Re_λ=50 and 70 (based on the Taylor microscale λ) allow for a preliminary assessment of the developed numerical model.

Manipulation of the governing equations for the scalar field (which are monotonic) reveals that the unboundedness of the scalar gradient magnitude is not ruled out by the mathematical properties of the correspondent conservation equation. Classic intermittency effects in the passive scalar field have been reproduced, such as non‐Gaussian behavior of the passive scalar statistics, loss of local isotropy, and multi‐fractal scaling of scalar structure functions. Moreover, Taylor and Richardson theories are, surprisingly, not confirmed only in the dissipation range (small‐scales anomalies).

The authors suggest that the origin of intermittency (qualitatively pictured here as violent burst in spatial gradient quantities) should be sought in the loss of monotonicity of the evolution equation of the scalar gradient.