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Abstract

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An Introduction to Algorithmic Finance, Algorithmic Trading and Blockchain
Type: Book
ISBN: 978-1-78973-894-0

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Article
Publication date: 6 December 2021

Saman Esmaeilian, Dariush Mohamadi, Majid Esmaelian and Mostafa Ebrahimpour

This paper aims to minimize the total carbon emissions and costs and also maximize the total social benefits.

Abstract

Purpose

This paper aims to minimize the total carbon emissions and costs and also maximize the total social benefits.

Design/methodology/approach

The present study develops a mathematical model for a closed-loop supply chain network of perishable products so that considers the vital aspects of sustainability across the life cycle of the supply chain network. To evaluate carbon emissions, two different regulating policies are studied.

Findings

According to the obtained results, increasing the lifetime of the perishable products improves the incorporated objective function (IOF) in both the carbon cap-and-trade model and the model with a strict cap on carbon emission while the solving time increases in both models. Moreover, the computational efficiency of the carbon cap-and-trade model is higher than that of the model with a strict cap, but its value of the IOF is worse. Results indicate that efficient policies for carbon management will support planners to achieve sustainability in a cost-effectively manner.

Originality/value

This research proposes a mathematical model for the sustainable closed-loop supply chain of perishable products that applies the significant aspects of sustainability across the life cycle of the supply chain network. Regional economic value, regional development, unemployment rate and the number of job opportunities created in the regions are considered as the social dimension.

Details

Journal of Modelling in Management, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1746-5664

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Article
Publication date: 30 November 2021

Supen Kumar Sah and Anup Ghosh

The purpose of this article is to carry out the thermal buckling analysis of power and sigmoid functionally graded material Sandwich plate (P-FGM and S-FGM) under uniform…

Abstract

Purpose

The purpose of this article is to carry out the thermal buckling analysis of power and sigmoid functionally graded material Sandwich plate (P-FGM and S-FGM) under uniform, linear, nonlinear and sinusoidal temperature rise.

Design/methodology/approach

Thermal buckling of FGM Sandwich plates namely, FGM face with ceramic core (Type-A) and homogeneous face layers with FGM core (Type-B), incorporated with nonpolynomial shear deformation theories are considered for an analytical solution in this investigation. Effective material properties and thermal expansion coefficients of FGM Sandwich plates are evaluated based on Voigt's micromechanical model considering power and sigmoid law. The governing equilibrium and stability equations for the thermal buckling analysis are derived based on sinusoidal shear deformation theory (SSDT) and inverse trigonometric shear deformation theory (ITSDT) along with Von Karman nonlinearity. Analytical solutions for thermal buckling are carried out using the principle of minimum potential energy and Navier's solution technique.

Findings

Critical buckling temperature of P-FGM and S-FGM Sandwich plates Type-A and B under uniform, linear, non-linear, and sinusoidal temperature rise are obtained and analyzed based on SSDT and ITSDT. Influence of power law, sigmoid law, span to thickness ratio, aspect ratio, volume fraction index, different types of thermal loadings and Sandwich plate types over critical buckling temperature are investigated. An analytical method of solution for thermal buckling of power and sigmoid FGM Sandwich plates with efficient shear deformation theories has been successfully analyzed and validated.

Originality/value

The temperature distribution across FGM plate under a high thermal environment may be uniform, linear, nonlinear, etc. In practice, temperature variation is an unpredictable phenomenon; therefore, it is essential to have a temperature distribution model which can address a sinusoidal temperature variation too. In the present work, a new sinusoidal temperature rise is proposed to describe the effect of sinusoidal temperature variation over critical buckling temperature for P-FGM and S-FGM Sandwich plates. For the first time, the FGM Sandwich plate is modeled using the sigmoid function to investigate the thermal buckling behavior under the uniform, linear, nonlinear and sinusoidal temperature rise. Nonpolynomial shear deformation theories are utilized to obtain the equilibrium and stability equations for thermal buckling analysis of P-FGM and S-FGM Sandwich plates.

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Article
Publication date: 30 November 2021

Latha Madhuri Poonem, Rajitha Gurijala, Sindhuja Ala and Malla Reddy Perati

The purpose of this paper is to investigate the effect of initial stress and heterogeneity on the propagation of torsional waves in dissipative medium. The problem…

Abstract

Purpose

The purpose of this paper is to investigate the effect of initial stress and heterogeneity on the propagation of torsional waves in dissipative medium. The problem consists of dry sand poroelastic half-space embedded between heterogeneous self-reinforced half-space and poroelastic medium. The frequency equation is derived in the framework of Biot's theory with some variants.

Design/methodology/approach

Torsional wave propagation in dry sand poroelastic half-space embedded between self-reinforced half-space and poroelastic medium. All the constituents here are assumed to be dissipative, heterogeneous and initial stressed.

Findings

Phase velocity and attenuation are computed against wavenumber for various values of self-reinforcement parameter, inhomogeneity parameter and initial stress. Particular cases are discussed in absence of dissipation. The numerical results are presented graphically.

Originality/value

Initial stress and heterogeneity effects on torsional waves in dry sand half-space between reinforced half-space and poroelastic medium are investigated. The frequency equation is derived, and which intern gives the phase velocity and attenuation coefficient for various values of initial stress, self-reinforcement parameter and heterogeneity parameter. From the numerical results, it is clear that as wavenumber varies phase velocity and attenuation are periodic in nature for all the cases. Particular cases are discussed in absence of dissipation. This kind of analysis can be extended to any elastic solid by taking magnetic, thermo and piezoelectric effects into account.

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Engineering Computations, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 29 October 2021

Frédérique Le Louër and María-Luisa Rapún

The purpose of this paper is to revisit the recursive computation of closed-form expressions for the topological derivative of shape functionals in the context of…

Abstract

Purpose

The purpose of this paper is to revisit the recursive computation of closed-form expressions for the topological derivative of shape functionals in the context of time-harmonic acoustic waves scattering by sound-soft (Dirichlet condition), sound-hard (Neumann condition) and isotropic inclusions (transmission conditions).

Design/methodology/approach

The elliptic boundary value problems in the singularly perturbed domains are equivalently reduced to couples of boundary integral equations with unknown densities given by boundary traces. In the case of circular or spherical holes, the spectral Fourier and Mie series expansions of the potential operators are used to derive the first-order term in the asymptotic expansion of the boundary traces for the solution to the two- and three-dimensional perturbed problems.

Findings

As the shape gradients of shape functionals are expressed in terms of boundary integrals involving the boundary traces of the state and the associated adjoint field, then the topological gradient formulae follow readily.

Originality/value

The authors exhibit singular perturbation asymptotics that can be reused in the derivation of the topological gradient function in the iterated numerical solution of any shape optimization or imaging problem relying on time-harmonic acoustic waves propagation. When coupled with converging Gauss−Newton iterations for the search of optimal boundary parametrizations, it generates fully automatic algorithms.

Details

Engineering Computations, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 16 November 2021

Karin L. Becker

This study aims to examine how members of Gen Z are impacted by Covid-19, specifically focusing on their professional opportunities, work preferences and future outlook.

Abstract

Purpose

This study aims to examine how members of Gen Z are impacted by Covid-19, specifically focusing on their professional opportunities, work preferences and future outlook.

Design/methodology/approach

A survey consisting of 24 questions including a Likert scale, multiple choice and open-ended was created to understand how members of Gen Z perceive Covid-19 impacting their education, employment, mental health and relationships. The survey was disseminated to employees of a corporate restaurant franchise, Christian college admissions and guidance non-profit, and online through social media including Instagram, Facebook, Reddit and LinkedIn. A total of 517 respondents completed the survey. Survey participants came from 29 states and 6 countries.

Findings

Results highlight Gen Z overwhelmingly values interpersonal connections, wants to Zoom less and work more in-person. The findings help anticipate potential professional gaps due to Covid-19 restrictions, as well as point out how Gen Z is markedly different in terms of workforce trends. Content analysis from an open-ended question reveals the extent of disruption Gen Z has experienced, adversely affecting their career plans and stalling professional development. Yet, despite these setbacks, Gen Z maintains a cautiously optimistic future outlook.

Research limitations/implications

Limitations to the study include the sample is largely comprising White women so the generalizability of results may be limited and the self-reporting nature of the survey may pose problems with method variance.

Practical implications

These findings have implications for Millennials as managers as they identify where resources should be invested including strengthening interpersonal communication skills, providing mentoring opportunities and appealing to their financial conservatism to recruit and retain Gen Z employees. The changes in telecommuting preferences and desire for more interpersonal and in-person communication opportunities highlight how Gen Z is markedly different than previous generations.

Social implications

Gen Z’s optimistic future outlook conveys a sense of resilience and strength in the face of stress. Rather than engaging in cognitive distortions and over generalizations when stressed, results show Gen Z is able to find healthy alternatives and maintain optimism in the face of stress. Additionally, due to the extent of isolation and loneliness Gen Zers reported, the value of in-person connections cannot be overstated. As results convey a sense of being overlooked and missing out on so many rites of passage, inviting Gen Zers to share how they have been impacted, recognizing their accomplishments and listening to them may go a long way to develop rapport.

Originality/value

This study differs from others because it takes a generational look at Covid-19 impacts. The qualitative nature allows us to hear from members of Gen Z in their own words, and as a generational cohort, their voices inform workplace attitudes, practices and managerial procedures.

Details

Management Research Review, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2040-8269

Keywords

Content available
Article
Publication date: 2 November 2021

Rabha Ibrahim

In this study, the authors introduce a solvability of special type of Langevin differential equations (LDEs) in virtue of geometric function theory. The analytic solutions…

Abstract

Purpose

In this study, the authors introduce a solvability of special type of Langevin differential equations (LDEs) in virtue of geometric function theory. The analytic solutions of the LDEs are considered by utilizing the Caratheodory functions joining the subordination concept. A class of Caratheodory functions involving special functions gives the upper bound solution.

Design/methodology/approach

The methodology is based on the geometric function theory.

Findings

The authors present a new analytic function for a class of complex LDEs.

Originality/value

The authors introduced a new class of complex differential equation, presented a new technique to indicate the analytic solution and used some special functions.

Details

Arab Journal of Mathematical Sciences, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1319-5166

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Article
Publication date: 4 November 2021

Qianyong Chen, Jinghua Xu and Shuyou Zhang

Compared with cusp height and area deviation ratio, volume error (VE) caused by the layer height could represent the stair-case effect more comprehensively. The proposed…

Abstract

Purpose

Compared with cusp height and area deviation ratio, volume error (VE) caused by the layer height could represent the stair-case effect more comprehensively. The proposed relative volume error (RVE)-based adaptive slicing method takes VE rather than cusp height as slicing criteria, which can improve part surface quality for functionalized additive manufacturing.

Design/methodology/approach

This paper proposes a volumetric adaptive slicing method of manifold mesh for rapid prototyping based on RVE. The pre-height sequences of manifold mesh are first preset to reduce the SE by dividing the whole layer sequence into several parts. A breadth-first search-based algorithm has been developed to generate a solid voxelization to get VE. A new parameter RVE is proposed to evaluate the VE caused by the sequence of the layer positions. The RVE slicing is conducted by iteratively adjusting the layer height sequences under different constraint conditions.

Findings

Three manifold models are used to verify the proposed method. Compared with uniform slicing with 0.2 mm layer height, cusp height-based method and area deviation-based method, the standard deviations of RVE of all three models are improved under the proposed method. The surface roughness measured by the confocal laser scanning microscope proves that the proposed RVE method can greatly improve part surface quality by minimizing RVE.

Originality/value

This paper proposes an RVE-based method to balance the surface quality and print time. RVE could be calculated by voxelized parts with required accuracy at a very fast speed by parallel.

Details

Rapid Prototyping Journal, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1355-2546

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Article
Publication date: 25 October 2021

Xinjian Ma, Shiqian Liu, Huihui Cheng and Weizhi Lyu

This paper aims to focus on the sensor fault-tolerant control (FTC) for civil aircraft under exterior disturbance.

Abstract

Purpose

This paper aims to focus on the sensor fault-tolerant control (FTC) for civil aircraft under exterior disturbance.

Design/methodology/approach

First, a three-step cubature Kalman filter (TSCKF) is designed to detect and isolate the sensor fault and to reconstruct the sensor signal. Meanwhile, a nonlinear disturbance observer (NDO) is designed for disturbance estimation. The NDO and the TSCKF are combined together and an NDO-TSCKF is proposed to solve the problem of sensor faults and bounded disturbances simultaneously. Furthermore, an FTC scheme is designed based on the nonlinear dynamic inversion (NDI) and the NDO-TSCKF.

Findings

The method is verified by a Cessna 172 aircraft model under bias gyro fault and constant angular rate disturbance. The proposed NDO-TSCKF has the ability of signal reconstruction and disturbance estimation. The proposed FTC scheme is also able to solve the sensor fault and disturbance simultaneously.

Research limitations/implications

NDO-TSCKF is the novel algorithm used in sensor signal reconstruction for aircraft. Then, disturbance observer-based FTC can improve the flight control system performances when the system with faults.

Practical implications

The NDO-TSCKF-based FTC scheme can be used to solve the sensor fault and exterior disturbance in flight control. For example, the bias gyro fault with constant angular rate disturbance of a civil aircraft is studied.

Social implications

Signal reconstruction for critical sensor faults and disturbance observer-based FTC for civil aircraft are useful in modern civil aircraft design and development.

Originality/value

This is the research paper studies on the signal reconstruction and FTC scheme for civil aircraft. The proposed NDO-TSCKF is better than the current reconstruction filter because the failed sensor signal can be reconstructed under disturbances. This control scheme has a better fault-tolerant capability for sensor faults and bounded disturbances than using regular NDI control.

Details

Aircraft Engineering and Aerospace Technology, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1748-8842

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Article
Publication date: 9 November 2021

Songmee Kim, Seyoon Jang, Woojin Choi, Chorong Youn and Yuri Lee

“Contactless service” refers to the use of technology in providing products or services without a salesperson. This study explores the mechanism underlying Millennial and…

Abstract

Purpose

“Contactless service” refers to the use of technology in providing products or services without a salesperson. This study explores the mechanism underlying Millennial and Generation Z (M/Z generations) consumers' preference for contactless service over salespersons in retail stores. In addition, this study tests differences between the M/Z generations.

Design/methodology/approach

The researchers predict characteristics to be antecedents of young consumer's preference for contactless service over salespersons and that the effects are mediated by technology self-efficacy. Next, a moderating variable (perceived consumer conformity) is added in the path between technology self-efficacy and the preference for contactless service. The hypotheses are tested among 142 Gen Z and 137 Millennial respondents.

Findings

The results show that M/Z generations’ characteristics significantly influence the preference for contactless service, except for security seeking. Also, interests in new technology and safety seeking are perceived higher by M/Z generations. The influence of technology self-efficacy on the preference for contactless service is moderated by social conformity.

Originality/value

As retail technology rapidly develops, the service industry is expected to change from the past, where salespersons played an important role, to contactless services. This study has academic and practical values, for the authors clarify the underlying psychological mechanisms of why young consumers prefer retail technology rather than communication with salespersons.

Details

Journal of Research in Interactive Marketing, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2040-7122

Keywords

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