Hassan Yousefi and Iradj Mahmoudzadeh Kani
The purpose of this study is to (1) improve the spectral features of the second-order uniformly non-oscillatory (UNO) slope limiters, and (2) numerical simulation of the…
Abstract
Purpose
The purpose of this study is to (1) improve the spectral features of the second-order uniformly non-oscillatory (UNO) slope limiters, and (2) numerical simulation of the unified-form of generalized fully-coupled saturated thermo-poro-elastic systems in the axisymmetric cylindrical coordinate via cell-adaptive Kurganov-Tadmor (KT) central high-resolution scheme using the UNO limiters.
Design/methodology/approach
(1) The spectral features of the UNO limiter are improved by compression-adaptive MINMOD (MM) limiters, achieved by blending different types of MM limiters to achieve less numerical dissipation and dispersion. These blended MM limiters preserve the total variation diminishing (TVD) feature over non-uniform non-centered cells. Also, the spectral features of the central schemes using the UNO limiters are investigated. (2) For the thermo-poro-elastic problem, corresponding first-order hyperbolic system is provided, including flux, source, diffusion and nonlinear terms. Where, there are different interacting components in the source and flux terms. The nonlinear terms are also considered by the Picard-like linearization concept.
Findings
Compression-adaptive UNO limiters would be stable over adapted cells with centered and non-centered cells. The benchmarks confirm that both spectral features and numerical accuracy are improved. For the generalized thermo-poro-elastic problem, corresponding responses including the shock waves can properly be captured.
Originality/value
Studying heat effects (e.g. hot fluid or freezing) and explosions on tunnels. Also, the UNO limiters could be used for simulations of various systems of conservation laws.
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This chapter develops a set of two-step identification methods for social interactions models with unknown networks, and discusses how the proposed methods are connected to the…
Abstract
This chapter develops a set of two-step identification methods for social interactions models with unknown networks, and discusses how the proposed methods are connected to the identification methods for models with known networks. The first step uses linear regression to identify the reduced forms. The second step decomposes the reduced forms to identify the primitive parameters. The proposed methods use panel data to identify networks. Two cases are considered: the sample exogenous vectors span Rn (long panels), and the sample exogenous vectors span a proper subspace of Rn (short panels). For the short panel case, in order to solve the sample covariance matrices’ non-invertibility problem, this chapter proposes to represent the sample vectors with respect to a basis of a lower-dimensional space so that we have fewer regression coefficients in the first step. This allows us to identify some reduced form submatrices, which provide equations for identifying the primitive parameters.
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In this paper, we study a partially linear dynamic panel data model with fixed effects, where either exogenous or endogenous variables or both enter the linear part, and the…
Abstract
In this paper, we study a partially linear dynamic panel data model with fixed effects, where either exogenous or endogenous variables or both enter the linear part, and the lagged-dependent variable together with some other exogenous variables enter the nonparametric part. Two types of estimation methods are proposed for the first-differenced model. One is composed of a semiparametric GMM estimator for the finite-dimensional parameter θ and a local polynomial estimator for the infinite-dimensional parameter m based on the empirical solutions to Fredholm integral equations of the second kind, and the other is a sieve IV estimate of the parametric and nonparametric components jointly. We study the asymptotic properties for these two types of estimates when the number of individuals N tends to ∞ and the time period T is fixed. We also propose a specification test for the linearity of the nonparametric component based on a weighted square distance between the parametric estimate under the linear restriction and the semiparametric estimate under the alternative. Monte Carlo simulations suggest that the proposed estimators and tests perform well in finite samples. We apply the model to study the relationship between intellectual property right (IPR) protection and economic growth, and find that IPR has a non-linear positive effect on the economic growth rate.
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Lillian T. Eby, Melissa M. Robertson and David B. Facteau
Interest in employee mindfulness has increased dramatically in recent years, fueled by several important conceptual articles, numerous studies documenting the benefits of…
Abstract
Interest in employee mindfulness has increased dramatically in recent years, fueled by several important conceptual articles, numerous studies documenting the benefits of mindfulness for employee outcomes, and the adoption of mindfulness-based practices in many Fortune 500 organizations. Despite this growing interest, the vast majority of research on employee mindfulness has taken an intrapersonal focus, failing to appreciate the ways in which mindfulness may enhance work-related relational processes and outcomes. The authors explore possible associations between mindfulness and relationally oriented workplace phenomena, drawing from interdisciplinary scholarship examining mindfulness in romantic relationships, child–parent relationships, patient–healthcare provider relationships, and student–teacher relationships. A framework is proposed that links mindfulness to three distinct relationally oriented processes, which are expected to have downstream effects on work-related relational outcomes. The authors then take the proposed framework and discuss possible extensions to a variety of unique workplace relationships and discuss critical next steps in advancing the relational science of mindfulness.
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Damian Tago, Henrik Andersson and Nicolas Treich
This study contributes to the understanding of the health effects of pesticides exposure and of how pesticides have been and should be regulated.
Abstract
Purpose
This study contributes to the understanding of the health effects of pesticides exposure and of how pesticides have been and should be regulated.
Design/methodology/approach
This study presents literature reviews for the period 2000–2013 on (i) the health effects of pesticides and on (ii) preference valuation of health risks related to pesticides, as well as a discussion of the role of benefit-cost analysis applied to pesticide regulatory measures.
Findings
This study indicates that the health literature has focused on individuals with direct exposure to pesticides, i.e. farmers, while the literature on preference valuation has focused on those with indirect exposure, i.e. consumers. The discussion highlights the need to clarify the rationale for regulating pesticides, the role of risk perceptions in benefit-cost analysis, and the importance of inter-disciplinary research in this area.
Originality/value
This study relates findings of different disciplines (health, economics, public policy) regarding pesticides, and identifies gaps for future research.
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Martin Götz and Ernest H. O’Boyle
The overall goal of science is to build a valid and reliable body of knowledge about the functioning of the world and how applying that knowledge can change it. As personnel and…
Abstract
The overall goal of science is to build a valid and reliable body of knowledge about the functioning of the world and how applying that knowledge can change it. As personnel and human resources management researchers, we aim to contribute to the respective bodies of knowledge to provide both employers and employees with a workable foundation to help with those problems they are confronted with. However, what research on research has consistently demonstrated is that the scientific endeavor possesses existential issues including a substantial lack of (a) solid theory, (b) replicability, (c) reproducibility, (d) proper and generalizable samples, (e) sufficient quality control (i.e., peer review), (f) robust and trustworthy statistical results, (g) availability of research, and (h) sufficient practical implications. In this chapter, we first sing a song of sorrow regarding the current state of the social sciences in general and personnel and human resources management specifically. Then, we investigate potential grievances that might have led to it (i.e., questionable research practices, misplaced incentives), only to end with a verse of hope by outlining an avenue for betterment (i.e., open science and policy changes at multiple levels).
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Francis J. Yammarino, Minyoung Cheong, Jayoung Kim and Chou-Yu Tsai
For many of the current leadership theories, models, and approaches, the answer to the question posed in the title, “Is leadership more than ‘I like my boss’?,” is “no,” as there…
Abstract
For many of the current leadership theories, models, and approaches, the answer to the question posed in the title, “Is leadership more than ‘I like my boss’?,” is “no,” as there appears to be a hierarchy of leadership concepts with Liking of the leader as the primary dimension or general factor foundation. There are then secondary dimensions or specific sub-factors of liking of Relationship Leadership and Task Leadership; and subsequently, tertiary dimensions or actual sub-sub-factors that comprise the numerous leadership views as well as their operationalizations (e.g., via surveys). There are, however, some leadership views that go beyond simply liking of the leader and liking of relationship leadership and task leadership. For these, which involve explicit levels of analysis formulations, often beyond the leader, or are multi-level in nature, the answer to the title question is “yes.” We clarify and discuss these various “no” and “yes” leadership views and implications of our work for future research and personnel and human resources management practice.
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Robert Straka and Tadeusz Telejko
The model of a shaft furnace operation is presented in this paper. Aim of this model is to predict concentrations of carbon monoxide and dioxide, the temperature of the lava and…
Abstract
Purpose
The model of a shaft furnace operation is presented in this paper. Aim of this model is to predict concentrations of carbon monoxide and dioxide, the temperature of the lava and the heat losses.
Design/methodology/approach
The mathematical model is based on 1D mass and heat balance laws for flue gas, coke and four materials used in a mineral wool production. Process parameters should be optimized for the minimal heat loss and the carbon monoxide concentration while keeping the prescribed lava temperature. The model consists of heterogeneous and homogeneous reactions for coke combustion, dolomite decomposition, rock and coke heating and a rock-melting model. The resulting system of partial differential equations is discretized by the finite volume method and solved with the explicit Euler scheme together with the point-implicit preconditioning of sources in species balance equations.
Findings
Numerical results are compared with the measured data on the pilot-scale device and show good agreement. It is found that in the lower region of the furnace, the large amount of carbon monoxide is present despite high oxygen levels.
Practical/implications
Based on the numerical model, the parameters of the secondary air stream could be studied (position, volume flux, oxygen enrichment and temperature) to decrease levels of carbon monoxide emissions while keeping lava temperature at needed levels.
Originality/value
The paper includes mathematical and numerical model needed for simulation of shaft furnaces in mineral wool industry. It can be used as a valuable tool for design engineers and furnace operators during research or redesign of existing devices.