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The purpose of this paper is to study the propagation of harmonic plane waves in a homogeneous anisotropic piezothermoelastic diffusive medium.

After developing the mathematical model and theoretical analysis of the problem, computational work has been performed to study the different characteristics of the plane harmonic waves.

The existence of waves namely, quasi-longitudinal wave (QP), quasi-thermal wave and quasi-mass diffusion wave have been found which propagates in an anisotropic piezothermoelastic diffusive medium. The different characteristics of waves like phase velocity and attenuation quality factor are computed numerically and presented graphically to show the piezoelectric effect.

A significant piezoelectric effects have been observed on the different characteristics of the waves in an anisotropic piezothermoelastic diffusive medium.

The purpose of this paper is to compute the phase velocities and attenuation coefficients of coupled longitudinal waves in a generalized thermoporoelastic model and to observe the effect of porosity, frequency and thermal parameters on the phase velocities and attenuation coefficients on these waves graphically.

The linear governing equations of a generalized thermoporoelastic model in the context of Lord and Shulman theory of generalized thermoelasticity are solved with the help of plane harmonic solution method to show the existence of one shear and three kinds of coupled longitudinal waves.

The results obtained show the dependence of phase velocities and attenuation coefficients of coupled longitudinal waves on frequency, porosity, relaxation times and other material parameters.

The problems on coupled heat‐fluid flow in a saturated deformable porous medium are important in various engineering fields, for example, petroleum engineering, chemical engineering, pavement engineering and nuclear waste management. A new generalized thermoporoelastic model is formulated to study the wave phenomena and their dependence on various material parameters.

This paper aims to concentrate on research that has been conducted in the previous decade on metamaterial (MTM)-based sensors for material characterization, which includes solid dielectrics, micro fluids and biomolecules.

There has been a vast advancement in sensors based on MTM since the past few decades. MTM elements provide a sensitive response to materials while having a tiny footprint, making them an appealing alternative for realizing diverse sensing devices.

Related research papers on MTM sensors published in reputable journals were reviewed in this report, with a specific emphasis on the structure, size and nature of the materials characterized. Because electromagnetic wave interaction excites MTM structures, sensing applications around the electromagnetic spectrum are possible.

The paper contains valuable information on MTM sensor technology for material characterization, and this study also highlights the challenges and approaches that will guide future development.

The purpose of this article is to investigate the propagation characteristics (such as particle motion, attenuation and phase velocity) of a Rayleigh wave in a nonlocal generalized thermoelastic media.

The bulk waves are represented with Helmholtz potentials. The stress-free insulated and isothermal plane surfaces are taken into account. Rayleigh wave dispersion relation has been established and is found to be complex. Due to the presence of radicals, the dispersion equation is continuously computed as a complicated irrational expression. The dispersion equation is then converted into a polynomial equation that can be solved numerically for precise complex roots. The extra zeros in this polynomial equation are eliminated to yield the dispersion equation’s roots. These routes are then filtered for inhomogeneous wave propagation that decays with depth. To perform numerical computations, MATLAB software is used.

In this medium, only one mode of Rayleigh wave exists at both isothermal and insulated boundaries. The thermal factors of nonlocal generalized thermoelastic materials significantly influence the particle motion, attenuation and phase velocity of the Rayleigh wave.

Numerical examples are taken to examine how the thermal characteristics of materials affect the existing Rayleigh wave’s propagation characteristics. Graphical analysis is used to evaluate the behavior of particle motion (such as elliptical) both inside and at the isothermal (or insulated) flat surface of the medium under consideration.

Attenuation characteristics of microstrip transmission lines on alumina substrates up to 50GHz are discussed. The lines under test came from three different manufacturers, each of whom used different processes to realise the transmission lines. Two of the manufacturers used silver (Ag) paste, whereas the process of one of the manufacturers was copper (Cu) based. Each manufacturer used identical alumina substrates and identical test pattern files so that the measured attenuation properties reflected manufacturer’s capability to fabricate microstrips and the quality of the metal system used. Measurements showed that the attenuation of copper microstrips was slightly lower than that of the silver microstrips, but the difference was small. Measured attenuation (S21) of about 50Ω microstrips was approximately 0.5db/cm at 30GHz and 0.8dB/cm at 50GHz, respectively. The loss coefficient, α_t, of about 0.035dB/mm at 40GHz was obtained for the Cu microstrips. Such an attenuation is reasonable for many practical applications in the microwave and millimetre wave regions.

Equipment reliability significantly impacts productivity, and in order to obtain high equipment reliability and productivity, maintenance and production decision should be made simultaneously to keep manufacturing system healthy. The purpose of this paper is to investigate the joint optimization of equipment maintenance and production decision for k-out-of-n system equipment with attenuation of product quality and to explore the impact of maintenance on the production and cost control for manufacturers.

A multi-period Markov chain model for k-out-of-n system equipment is set up based on the assumption that the deterioration of equipment is a pure birth process. Then, the maintenance cost, setup cost, inventory holding cost, shortage cost, production cost and the quality cost are analyzed with the uncertain demand and the attenuation of product quality stemmed from equipment deterioration. The total lowest cost per unit time and its specific calculation method are presented. Finally, the robustness and flexibility of the method are verified by a numerical example and the effects of equipment deterioration intensity and attenuation of product quality are analyzed.

The result shows that the joint decision model could not only satisfy the uncertain demand with low cost and strong robustness but also make the output products high quality level. In addition, the attenuation of product quality would influence the equipment maintenance and production decision and leads to the production waste and increases the operation cost greatly.

Implications derived from this study can help production maintenance managers and reliability engineers adequately select maintenance policy to improve the equipment efficiency and productivity with high quality level at a relatively low cost.

The accuracy of sensor location estimation influences directly the quality and reliability of services provided by a wireless sensor network (WSN). However, current localization methods may require additional hardware, like global positioning system (GPS), or suffer from inaccuracy like detecting radio signals. It is not proper to add extra hardware in tiny sensors, so the aim is to improve the accuracy of localization algorithms.

The original signal propagation‐based localization algorithm adopts a static attenuation factor model and cannot adjust its modeling parameters in accordance with the local environment. In this paper an adaptive localization algorithm for WSNs that can dynamically adjust ranging function to calculate the distance between two sensors is presented. By adjusting the ranging function dynamically, the location of a sensor node can be estimated more accurately.

The NCTUNs simulator is used to verify the accuracy and analyze the performance of the algorithm. Simulation results show that the algorithm can indeed achieve more accurate localization using just a small number of reference nodes in a WSN.

There is a need to have accurate location information of reference nodes.

This is an effective low‐cost solution for the localization of sensor nodes.

An adaptive localization algorithm that can dynamically adjust ranging function to calculate the distance between two sensors for sensor network deployment and providing location services is described.

Tourism employment is very diverse ranging from precarious, exploitative study to high-quality workplaces. However, poor employment images dominate the tourism industry, which makes attracting employees difficult. This study aims to examine the processes that lead to such image construction.

Using a qualitative methodology, the study develops a multilevel framing cycle comprising a media analysis of newspapers and magazines (macro-level), a conversation analysis of peer communication/negotiations (meso-level) and a content analysis of single employee/manager interviews (micro-level); and a comparative analysis of the macro-, meso- and micro-level findings.

The multilevel frame cycle identifies image-construction processes that pass through working conditions, payment, seasonality and human resource problems. These processes are shaped by the two cross-level dynamics of radicalization and attenuation. The latter consists of rationalized and repressed framings of tourism employment images (TEI) and the former consists of ideological and emotional framings.

Tourism stakeholders should support and participate in a pragmatic and open dialog to overcome the radicalization and attenuation of tourism employment. The key players require a new deal to end the “information warfare” on tourism employment, inaugurating a new era of collaborative and constructive employment relations.

This study develops a holistic and dynamic understanding of TEI by exploring how media products, peer groups and employees/managers jointly construct these images. It demonstrates how attenuation and radicalization shape poor employment images in tourism. It argues that these dynamics “lock in” the status-quo, create mutual recrimination between employers and employees and counteract common strategies that could otherwise improve employment structures and the image of tourism.

The purpose of this paper is to use de Sitter's design theory to show how organizational structures can be designed so as to attenuate organizational disturbances and amplify regulatory potential. It is argued that organizational structures with low values on so‐called design‐parameters are themselves no source of disturbances and have the required built‐in regulatory potential.

Key concepts from de Sitter's design theory are introduced and used to show how structures can attenuate disturbances and amplify regulatory potential.

The analysis in this paper deepens our understanding of the role of organizational structures for dealing with organizational complexity, and of the design parameters that should be manipulated to achieve structural attenuation and amplification.

Having a structure permitting organizations to attenuate and amplify is a crucial condition for organizational viability. This paper provides guidelines for the design of such structures.

This is one of a limited number of studies that makes apparent how general insights from (management) cybernetic (e.g. viability, attenuation and amplification) may be realized in organizations by their structural design.

This paper examines the competitive dimensions of quality for first tier suppliers in the automotive industry. A theoretically relevant set of quality variables is identified from the literature. The results of a factor analysis show that quality is a two dimensional construct in the automotive supply industry. The core dimensions of quality are: product quality, which is primarily focused on design superiority and performance of the physical product; and service quality, which comprises both pre‐ and post‐sale service. The study reveals that both product quality and service quality are related to overall firm performance, regardless of whether asset based, investment based, or market based measures are used.