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1 – 10 of over 67000Vijay Chawla, Sanjeev Ahuja and Varsha Rani
The purpose of this paper is to study the fundamental solution in transversely isotropic micropolar thermoelastic media. With this objective, the two-dimensional general solution…
Abstract
Purpose
The purpose of this paper is to study the fundamental solution in transversely isotropic micropolar thermoelastic media. With this objective, the two-dimensional general solution in transversely isotropic thermoelastic media is derived.
Design/methodology/approach
On the basis of the general solution, the fundamental solution for a steady point heat source on the surface of a semi-infinite transversely isotropic micropolar thermoelastic material is constructed by six newly introduced harmonic functions.
Findings
The components of displacement, stress, temperature distribution and couple stress are expressed in terms of elementary functions. From the present investigation, a special case of interest is also deduced and compared with the previous results obtained.
Practical implications
Fundamental solutions can be used to construct many analytical solutions of practical problems when boundary conditions are imposed. They are essential in the boundary element method as well as the study of cracks, defects and inclusions.
Originality/value
Fundamental solutions for a steady point heat source acting on the surface of a micropolar thermoelastic material is obtained by seven newly introduced harmonic functions. From the present investigation, some special cases of interest are also deduced.
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Hui Wang and Qinghua Qin
The purpose of this paper is to present a new special element model for thermal analysis of composites.
Abstract
Purpose
The purpose of this paper is to present a new special element model for thermal analysis of composites.
Design/methodology/approach
A hybrid finite element formulation taking the fundamental solution as kernel function is presented in this work for analyzing the thermal behavior and predicting the effective thermal conductivity of fiber‐reinforced composites. A representative volume cell containing single or multiple fibers (or inclusions) is considered to investigate the overall temperature distribution affected by the inclusions and the interactions among them, and to evaluate the effective thermal conductivity of the composites using the presented algorithm with special‐purpose inclusion elements. Numerical examples are presented to demonstrate the accuracy and applicability of the proposed method in analyzing fiber‐reinforced composites.
Findings
The independent intra‐element field and frame field, as well as the newly‐developed hybrid functional, make the algorithm versatile in terms of element construction, with the result that the related variational functional involves the element boundary integral only. All numerical results are compared with the solutions from ABAQUS and good agreement is observed for all cases, clearly demonstrating the potential applications of the proposed approach to large‐scale modeling of fiber‐reinforced composites. The usage of special inclusion element can significantly reduce model meshing effort and computing cost, and simultaneously avoid mesh regeneration when the fiber volume fraction is changed.
Practical implications
Due to the fact that the established special elements exactly satisfy the interaction of matrix and fiber within the element, only element boundary integrals are involved, thus the algorithm can significantly reduce modeling effort and computing cost with less elements, and simultaneously avoid mesh regeneration when the fiber volume fraction is changed.
Originality/value
Based on the special fundamental solution, a newly‐constructed inclusion element is applied to a number of test problems involving unit RVCs with multiple fibers to access the accuracy of the model. The effective thermal conductivity of the composites is evaluated for cases of single and multiple fibers using the average temperatures at certain points on a data‐collection surface. A new algorithm for evaluating effective properties with special elements is presented.
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Matin Mohaghegh and Andreas Größler
Adopting the dynamic capability perspective, this study aims at exploring which problem-solving capabilities result in fundamental solutions with a potentially low likelihood for…
Abstract
Purpose
Adopting the dynamic capability perspective, this study aims at exploring which problem-solving capabilities result in fundamental solutions with a potentially low likelihood for problems to recur. This can also shed light on why, despite many attempts, process improvement programs often fail to produce such long-term solutions.
Design/methodology/approach
A case study is carried out to inductively describe and classify problem-solving in companies and to indicate why problem-solving efforts are typically bounded to short-term solutions. The empirical findings are triangulated with findings from the extant literature.
Findings
First, the authors propose three problem-solving modes with different characteristics and potential impacts on operational performance: intuitive problem-solving, semi-structured problem-solving and systematic problem-solving. Second, by emphasizing dynamic capabilities' micro-foundations and with the focus on learning mechanisms, the authors show that, among these modes, only systematic problem-solving can serve as a dynamic capability with fundamental solutions. Third, based on insights from the case study, the authors address behavioral and organizational impediments that curb dynamic capabilities and limit systematic problem-solving adoption.
Originality/value
This study is an empirically informed attempt to understand systematic problem-solving as a dynamic capability. The authors uncover the micro-foundations and the learning mechanisms through which systematic problem-solving becomes a dynamic capability. By highlighting problem-solving orientation as a hardly investigated dimension of improvement programs, the authors show that a mixture of a static problem-solving approach and a set of impediments at both individual and organizational levels is the major reason of failures of improvement programs over time.
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Abstract
Purpose
The purpose of this paper is to analyze the crowd stampede risk mechanism from the perspective of systems thinking.
Design/methodology/approach
Causal loop diagram is drawn to outline the non-linear interactions among complex factors across the whole system and dissect the contributory factors of crowd stampede accident. To systematically construct the theoretical framework and find fundamental solutions, co-word analysis with Citespace is used to get the critical data. An agent-based simulation using Pathfinder is conducted to develop a spatial model for the Shanghai Stampede Accident that happened in 2014.
Findings
The causal loop diagram is formed to not only illustrate the symptomatic solutions with a quick fix but also dissect the fundamental solutions through an underlying systemic analysis. The simulation shows that crowd stampede experiences an interactive process of accumulation, trigger, delay, break and diffusion of risk factors within the crowd system. A linkage effect among the multidimensional characters of individuals and the system accelerates the stampede risk deterioration. There exists delay of the result of effect from the deep-level measure.
Practical implications
A top-down approach is offered to policymakers for crowd stampede risk protocol design and synergic emergency control that may reduce the risk of the stampede.
Originality/value
In this study, SDFT paradigm is proposed as the critical solution for the crowd stampede accident. In addition, a chain effect of energy and a linkage effect within the crowd system is illustrated for in-depth understanding of crowd stampede risk.
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FR. Oswald A. J. Mascarenhas, S.J.
Morality is primarily a system of values, meanings, convictions, beliefs, principles, and drivers of good behavior and good outcomes in any organization. Using systems thinking…
Abstract
Executive Summary
Morality is primarily a system of values, meanings, convictions, beliefs, principles, and drivers of good behavior and good outcomes in any organization. Using systems thinking concepts and applications introduced and developed during the last 50 years or so by various scholars from MIT, Stanford, and Wharton, such as Chris Argyris, Russell Ackoff, G. K. Forrester, Peter Senge, Stephen Covey, and Jim Collins, this chapter seeks to explore various past and contemporary market systems and challenges in terms of specific inputs, processes, and outputs. Systems thinking reckons everything in the cosmos (usually classified as subjects, objects, properties, and events) as a system (composed of two or more interactive parts with individual and interactive effects) that is connected to every other system in the universe. Various systems thinking laws and archetypes that have been developed thus far by systems thinkers will be introduced in order to identify basic patterns, structures, and constraints of human thinking and reasoning that create market phenomena. The academic and managerial challenge is to identify, explore, and capitalize such nonobvious connections for creating and developing new markets and corporate growth opportunities in the highly turbulent markets of today. In a globalized, digitized, and networked planet and universe, systems thinking is a very effective tool for analyzing turbulent market systems holistically and in an inclusive and integrated manner, with their specific inputs, processes, and outcomes. Several contemporary market cases will be included to illustrate the contents of this chapter.
Oswald A. J. Mascarenhas, Munish Thakur and Payal Kumar
Systems thinking calls for a shift of our mindset from seeing just parts to seeing the whole reality in its structured dynamic unity and interconnectedness. Systems thinking…
Abstract
Executive Summary
Systems thinking calls for a shift of our mindset from seeing just parts to seeing the whole reality in its structured dynamic unity and interconnectedness. Systems thinking fosters a sensibility to see subtle connections between components and parts of reality, especially the free enterprise capitalist system (FECS). It enables us to see ourselves as active participants or partners of FECS and not mere induced factors of its production–distribution–consumption processes. Systems thinking seeks to identify the economic “structures” that underlie complex situations in FECS that bring about high versus low leveraged changes. A system is strengthened and reinforced by feedback of reciprocal exchanges that makes the system alive, transparent, human, and humanizing.
In Part I, we explore basic laws or patterns of behaviors as understood by systems thinking; in Part II we examine the basic archetypes or structured behaviors of systems thinking; in both parts we strive to see reality through the lens of critical thinking to help us understand patterns and structures of behavior among systems and their component parts. In conclusion, we argue for compatibility and complementarity of critical thinking and systems thinking to identify and resolve management problems created by our flawed thinking, and sedimented by our wanton assumptions, presumptions, suppositions and presuppositions, biases, and prejudices. Such thinking will also identify unnecessary economic and political structures of the self-serving policies we create, which imprison us.
J. Lim, C.L. Chan and A. Chandra
A boundary element method (BEM) formulation for the solutionof transient conduction‐convection problems is developed in thispaper. A time‐dependent fundamental solution for moving…
Abstract
A boundary element method (BEM) formulation for the solution of transient conduction‐convection problems is developed in this paper. A time‐dependent fundamental solution for moving heat source problems is utilized for this purpose. This reduces the governing parabolic partial differential equations to a boundary‐only form and obviates the need for any internal discretization. Such a formulation is also expected to be stable at high Peclet numbers. Numerical examples are included to establish the validity of the approach and to demonstrate the salient features of the BEM algorithm.
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Aimin Jiang, Haojiang Ding and Guoquan Wu
Based on the governing equations of magneto‐electro‐elastic media, the general solutions in the case of distinct eigenvalues and is introduced and expressed in four harmonic…
Abstract
Based on the governing equations of magneto‐electro‐elastic media, the general solutions in the case of distinct eigenvalues and is introduced and expressed in four harmonic functions. Then, the Green’s functions for point forces, point charge and point current acting in the interior of a two‐phase infinite magneto‐electro‐elastic plane in the case of distinct or multiple eigenvalues are given using the method of mirror image source.
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Saeed Ur Rahman and José Luis Díaz Palencia
This article aims to study a model of flame propagation in a nonhomogeneous medium with a p-Laplacian operator. The intention with such operator is to model the effects of slow…
Abstract
Purpose
This article aims to study a model of flame propagation in a nonhomogeneous medium with a p-Laplacian operator. The intention with such operator is to model the effects of slow and fast diffusion, that can appear in a nonhomogeneous media, depending on the pressure driven conditions. In addition, the authors introduce a general form in the reaction term, that introduces the flame chemical kinetics.
Design/methodology/approach
To introduce the governing equations, the authors depart from previously reported models in flame propagation, but the authors consider a new modeling approach based on a p-Laplacian operator.
Findings
The authors provide evidences of regularity and uniqueness of solutions. Afterward, the authors introduce profiles of stationary solutions based on the definition of a Hamiltonian for the newly discussed model. Eventually, the authors obtain exponential profiles solutions with the help of a scaling, that transforms the model into a nonlinear Hamilton–Jacobi equation.
Originality/value
The new model has not been previously reported in the literature. The authors consider that the mathematical properties of a p-laplacian (in particular the property known as finite propagation) is of inherent interest to model pressure drive flames with slow or fast diffusion. Indeed, the authors’ approach has the value of providing an operator that can fit better to model flame propagation. In addition, the authors introduce a general form of chemical kinetics, to make the authors’ model further general.
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Oswald A. J. Mascarenhas, Munish Thakur and Payal Kumar
All of us are born critical thinkers; some perfect this talent; others ignore it as useful in daily life. This chapter follows those who perfected this talent in order to learn…
Abstract
Executive Summary
All of us are born critical thinkers; some perfect this talent; others ignore it as useful in daily life. This chapter follows those who perfected this talent in order to learn from them the art and models of critical thinking in terms of its optimal inputs, processes, and outputs. According to great critical thinkers in business management, critical thinking questions – or should question – the obsessive generalizations, constraints, and “best” practices of the prevailing system of management, and try to replace them with more valid assumptions and more meaningful generalizations that uphold the dignity, uniqueness, and inalienable rights of the individual person and the community. After setting out some cases illustrating the lack of critical thinking, in Part I of this chapter, we introduce some representative management thinkers on critical thinking, and in Part II, we introduce eight models or practical approaches for critical thinking.