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The purpose of the study is to obtain and analyze vibro-acoustic characteristics.

A unified analysis model for the rotary composite laminated plate and conical–cylindrical double cavities coupled system is established. The related parameters of the unified model are determined by isoparametric transformation. The modified Fourier series are applied to construct the admissible displacement function and the sound pressure tolerance function of the coupled systems. The energy functional of the structure domain and acoustic field domain is established, respectively, and the structure–acoustic coupling potential energy is introduced to obtain the energy functional. Rayleigh–Ritz method was used to solve the energy functional.

The displacement and sound pressure response of the coupled systems are acquired by introducing the internal point sound source excitation, and the influence of relevant parameters of the coupled systems is researched. Through research, it is found that the impedance wall can reduce the amplitude of the sound pressure response and suppress the resonance of the coupled systems. Besides, the composite laminated plate has a good noise reduction effect.

This study can provide the theoretical guidance for vibration and noise reduction.

The purpose of this paper is to develop a novel electromagnetic-based acoustic energy harvester (EH) for the application of wireless autonomous sensors.

The developed acoustic EH comprises a Helmholtz resonator (HR), a suspension system that consists of a flexible membrane and a permanent magnet, a couple of coils and a coil holder. Furthermore, the HR, used in the harvester, is designed for a specific resonant frequency based on simulation carried out in COMSOL Multiphysics®.

The developed harvester is tested both in lab under harmonic sound pressure levels (SPLs) and in real environment under random SPLs. In lab, when exposed to 100 dB SPL, the harvester generated a peak power of 212 µW. Furthermore, in real environment in vicinity of electric generator, the harvester produced an output voltage of about 110 mV collectively from its both coils.

In this paper, a novel geometric configuration for electromagnetic-based acoustic EH is proposed. In the developed harvester, two coils are placed in it to achieve enhanced electrical output from it for the first time.

Wireless sensor networks (WSN), as a solution for buried water pipe monitoring, face a new set of challenges compared to traditional application for above-ground infrastructure monitoring. One of the main challenges for underground WSN deployment is the limited range (less than 3 m) at which reliable wireless underground communication can be achieved using radio signal propagation through the soil. To overcome this challenge, the purpose of this paper is to investigate a new approach for wireless underground communication using acoustic signal propagation along a buried water pipe.

An acoustic communication system was developed based on the requirements of low cost (tens of pounds at most), low power supply capacity (in the order of 1 W-h) and miniature (centimetre scale) size for a wireless communication node. The developed system was further tested along a buried steel pipe in poorly graded SAND and a buried medium density polyethylene (MDPE) pipe in well graded SAND.

With predicted acoustic attenuation of 1.3 dB/m and 2.1 dB/m along the buried steel and MDPE pipes, respectively, reliable acoustic communication is possible up to 17 m for the buried steel pipe and 11 m for the buried MDPE pipe.

Although an important first step, more research is needed to validate the acoustic communication system along a wider water distribution pipe network.

This paper shows the possibility of achieving reliable wireless underground communication along a buried water pipe (especially non-metallic material ones) using low-frequency acoustic propagation along the pipe wall.

Reducing noise and vibration is an increasingly important objective for designers and users of a wide range of mechanical systems. Lubricants can contribute to reduction of overall noise and vibration generated by machines, both by reducing generation of acoustic energy in lubricated contacts and by modulating the transmission of vibration through the lubricant. This paper outlines various mechanisms by which the lubricant may affect the generation and transmission of acoustic vibration. Examples from the area of refrigeration compressor lubrication are presented, demonstrating that correct design and selection of lubricant can have a significant impact on noise and vibration.

The main purpose of this study was to evaluate the mechanical behaviour of layered fibrous carbon-fibre reinforced plastic (CFRP) under complex low-speed bending and impact loads and subsequent cyclic tensile loads.

A comprehensive approach was adopted to study the damage accumulation processes using state-of-the-art testing and diagnostic equipment. In the course of the study, a microstructure analysis of damages caused by a transverse impact and cyclic tension was performed.

A dependence of residual fatigue life of the studied composite material on the intensity of the preliminary impact bending was established. Temperature field distribution fields on the surface of the sample during tests were shown. Data on damage accumulation processes were presented, which were obtained during the registration of acoustic emission signals.

A connection was established between changes of registered acoustic response signals and thermal imaging camera data, which was supported by the results of an experimental study. The results of the comprehensive approach showed a qualitative correlation.

To provide a comprehensive picture of the wide range of technical, operational, and management issues that must be considered when developing, acquiring or using less lethal weapons for law enforcement agencies.

The source of the insights provided in this paper come from a careful reading and critique of the less lethal technology literature and the organization of and participation in many less lethal weapon technology conferences, technical working groups, and peer review panels.

The essential attributes of less lethal weapons for law enforcement applications are described as well as the many practical considerations that must be made when acquiring and using them.

This review should help law enforcement and corrections agencies make more informed decisions on the acquisition and deployment of less lethal weapons and should also be a useful starting point for weapon developers.

Scientists and engineers seeking to develop new or improved less lethal weapons for law enforcement will benefit from having in one source a basic insight into the complexities and challenges of producing a successful less lethal weapon. Non‐technical professionals will gain a greater understanding of the difficulty in producing less lethal weapons that are both very effective and very safe, but also affordable and practical.

The United Nations has demonstrated a commitment to preserving the ecosystem through its 2030 sustainable development goals agenda. One crucial objective of these goals is to promote a healthy ecosystem and discourage practices that harm it. Building materials production significantly contributes to the emissions of greenhouse gases. This poses a threat to the ecosystem and prompts a growing demand for sustainable building materials (SBMs). The purpose of this study is to investigate SBMs to determine their utilization in construction operations and the potential impact their application could have on construction productivity.

A systematic review of the existing literature in the field of SBMs was conducted for the study. The search strings used were “sustainable” AND (“building” OR “construction”) AND “materials” AND “productivity”. A total of 146 articles were obtained from the Scopus database and reviewed.

Bio-based, cementitious and phase change materials were the main categories of SBMs. Materials in these categories have the potential to substantially contribute to sustainability in the construction sector. However, challenges such as availability, cost, expertise, awareness, social acceptance and resistance to innovation must be addressed to promote the increased utilization of SBMs and enhance construction productivity.

Many studies have explored SBMs, but there is a dearth of studies that address productivity in the context of SBMs, which leaves a gap in understanding. This study addresses this gap by drawing on existing studies to determine the potential implications that using SBMs could have on construction productivity.

A balanced armature receiver (BAR) as a special type of electromagnetic acoustic transducers plays a significant role in reproduction of music and speech, active noise control in modern hearing aid and in contemporary in-ear monitors. This paper aims to present a static analysis of the balanced armature receiver based on the lumped network approach (LNA) and the finite element method (FEM).

In this paper, the LNA and two-dimensional FEM are applied to model deflections of the BAR’s armature from the equilibrium position. Results of calculations are compared with measurements.

The derived analytical formulas and developed procedure allow for calculation of the armature deflection.

Comparing to the previous papers, the reluctance’s nonlinearity of the armature has been considered.

The pressure control valve is a possible means of overcoming the effects of compliance between a hydraulic servo and its load. The valve consists of two stages; an open‐centre flow control valve schematically analogous to a resistance bridge, and a split‐slider valve. In order to study the dynamics of the system it is convenient to set up an electrical analogue for the mechanical system. This will give the non‐linear equations of the system. Several forms of the various impedance elements making up the system require consideration. The resistance of a length of hydraulic line can be obtained from the friction factor and will depend on the flow regime which prevails. In developing an expression for the inductance of a length of line the assumption is made that the wavelength of the oscillatory motion is long compared with the line length. In considering the resistance of orifices it is necessary to take into account the three regimes for flow through an orifice, laminar, transition, and turbulent flow. The inductive effect of an orifice arises from the acceleration of the fluid as the streamlines converge through the orifice; an expression can be derived by applying Newton's second law of motion to the column of oil passing through the orifice. The effective capacitance of a volume can be derived by considering wave motion in one dimension. An expression for the radiation resistance of a piston is derived, and also one for the incident and reflected waves. In constructing the electrical analogue for the slider valve the mass and viscous damping of the slider as well as Bernoulli forces must be represented.

The urgency to address climate change and its devastating consequences has never been more pressing. As societies become increasingly aware of the detrimental impact of traditional housing on the planet, there is a growing demand for eco-friendly housing solutions that prioritize energy efficiency, resource conservation and reduced carbon emissions. Therefore, this study aims to investigate the factors that influence customers’ priority toward eco-friendly house purchasing intention.

This study collected 386 data using a quantitative research strategy and purposive sampling method. This study uses a hybrid analysis technique using partial least squares structural equation modeling (PLS-SEM) and fuzzy-set qualitative comparative analysis (fsQCA) approaches to identify the influencing factors.

The PLS-SEM analysis found that attitude toward the eco-friendly house, subjective norms, performance expectancy, environmental knowledge and environmental sensitivity have a positive influence on eco-friendly house purchasing intention. However, perceived behavioral control and willingness to pay were found to have insignificant effect on customers’ intention to purchase eco-friendly houses. The fsQCA results further revealed complex causal relationships between the influencing factors.

This research will not only contribute to academic knowledge but also provide practical guidance to real estate developers, policymakers and individuals looking to make environmentally responsible choices. By understanding the factors that influence consumers’ intentions to purchase eco-friendly houses, we can pave the way for a more sustainable and resilient future.

This study has used a hybrid analysis technique, combining PLS-SEM and fsQCA, to enhance the predictive accuracy of eco-friendly house purchase intentions among individuals residing in densely populated and highly polluted developing countries, such as Bangladesh.