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Design codes include serviceability limit state (SLS) provisions for stress, crack, and deflection control in concrete structures, which may limit the structural design. When drawing on reinforced ultra‐high performance fibre‐reinforced concrete (R‐UHPFRC), the process of cracking differs significantly from traditional concretes. Thus, it remains unclear whether the traditional provisions are applicable to R‐UHPFRC or should be reviewed. Uniaxial tensile tie test is an excellent option to analyse and review these criteria. This work proposes a novel test methodology to study the behaviour of R‐UHPFRC under serviceability conditions, which lets the study of the global and local deformation behaviour by using different measurement equipment. Two different types of R‐UHPFRC ties with variant fibre content were tested. The global average tensile stress–strain curve, cracking behaviour, number, and width of cracks were obtained. Promising preliminary results admitted that this methodology can be useful to propose design criteria of R‐UHPFRC under SLS. [ABSTRACT FROM AUTHOR]

Up to now, no studies have been yet reported to study the mechanical behaviors of three dimensionally functionally graded (FG) shell structures. In this paper, the free vibration of three dimensionally FG nanoplates and nanoshells are investigated for the first time. All of the mechanical properties expect passion's ratio are assumed to be changed along the length, width and thickness directions, which can vary according to an arbitrary function. The small scale effect due to nanostructures is considered based on nonlocal Eringen's theory where Hamilton's principle is adopted to derive the equations of motion. Galerkin solution method is adopted to obtain the natural frequencies of the FG nanostructures. Dynamic results are reported for nanoplates, spherical nanoshells, and cylindrical nanoshells for simply supported boundary conditions. The influences of several parameters, such as nonlocal parameter and functionally graded indexes are investigated on the natural frequency of the nanostructures. The results of the presented study can be served as benchmarks for future mechanical analysis of three-dimensionally FG shell structures. [ABSTRACT FROM AUTHOR]

AbstractThis investigation focuses on the nonlinear behavior of porosity-dependent functionally graded (FG) truncated conical small-scale structures. The modified coupled stress theory, as well as the energy method, are applied to generate the nonlinear partial differential equations (PDEs) related to buckling analysis of simply supported nonuniform micro-cylindrical structures. The material dispersion is gradually changed along the length of the structures between the Nickel and concrete, while the porosity voids are scattered in the radial direction, and the external radius of the structure decreases along the length direction via nonlinear mathematic equations applicable in sports structures. The PDEs are numerically solved via the generalized differential quadrature method (GDQM) coupled with the numerical iterative technique. In this particular context, the aim is to predict nonlinear results using a newly developed methodology that employs artificial neural networks (ANNs). The predictions generated by this approach will be compared against previously obtained data and validated to ensure their accuracy and reliability. The ANN methodology is expected to provide a more robust and comprehensive framework for predicting nonlinear results, which would be helpful in a variety of settings, from scientific research to engineering applications. [ABSTRACT FROM AUTHOR]

This study proposes a novel test method and corresponding procedure to evaluate how coconut fibres affect crack propagation rates resulting from plastic shrinkage during the accelerated drying of concrete slabs. The experiment employed concrete plate specimens, which were used to simulate slab structural elements with a surface dimension notably greater than their thickness. These slabs were reinforced with coconut fibre with 0.5%, 0.75%, and 1% fibre content. A wind tunnel was designed to simulate two significant climate parameters (wind speed and air temperature), which could impact the cracking behaviour of surface elements. The proposed wind tunnel allowed air temperature to be controlled alongside wind speed while monitoring moisture loss and the cracking propagation process. During testing, a photographic recording method was used to evaluate cracking behaviour, with the total crack length serving as a parameter to assess the impact of fibre content on the crack propagation of slab surfaces. Additionally, crack depth was measured using ultrasound equipment. The results indicate that the proposed test method was appropriate for future research, allowing for the evaluation of the effect of natural fibres on the plastic shrinkage behaviour of surface elements under controlled environmental conditions. Based on initial studies and the results obtained through the proposed test method, concrete containing 0.75% fibre content exhibited significantly reduced crack propagation on slab surfaces, as well as a reduction in the crack depth caused by plastic shrinkage during the early age of the concrete. [ABSTRACT FROM AUTHOR]

Agriculture is a leading sector in international initiatives to mitigate climate change and promote sustainability. This article exhaustively examines the removals and emissions of greenhouse gases (GHGs) in the agriculture industry. It also investigates an extensive range of GHG sources, including rice cultivation, enteric fermentation in livestock, and synthetic fertilisers and manure management. This research reveals the complex array of obstacles that are faced in the pursuit of reducing emissions and also investigates novel approaches to tackling them. This encompasses the implementation of monitoring systems powered by artificial intelligence, which have the capacity to fundamentally transform initiatives aimed at reducing emissions. Carbon capture technologies, another area investigated in this study, exhibit potential in further reducing GHGs. Sophisticated technologies, such as precision agriculture and the integration of renewable energy sources, can concurrently mitigate emissions and augment agricultural output. Conservation agriculture and agroforestry, among other sustainable agricultural practices, have the potential to facilitate emission reduction and enhance environmental stewardship. The paper emphasises the significance of financial incentives and policy frameworks that are conducive to the adoption of sustainable technologies and practices. This exhaustive evaluation provides a strategic plan for the agriculture industry to become more environmentally conscious and sustainable. Agriculture can significantly contribute to climate change mitigation and the promotion of a sustainable future by adopting a comprehensive approach that incorporates policy changes, technological advancements, and technological innovations. • AI-driven Solutions for Green Agriculture: Mitigating Emissions, Enhancing Sustainability. • Navigating the Climate Challenge: Assessing GHG Emissions in Agriculture with Precision. • Cultivating Tomorrow: Balancing Emissions, Carbon Sequestration, and Innovative Technologies. • Sustainable Agriculture in the AI Era: A Holistic View of Emissions Reduction Strategies. [ABSTRACT FROM AUTHOR]

In this article, amplitude, and vibrational characteristics of a rotating orthotropic piezoelectric nanodisk are presented. The centrifugal and Coriolis effects due to the rotation are considered. The strains and stresses can be determined via the higher-order shear deformable theory (HSDT). For accessing to size effects, the nonlocal strain gradient theory (NSGT) is used for obtaining the correct results. The boundary conditions are derived through governing equations of the orthotropic piezoelectric rotating nanodisk using an energy method known as Hamilton's principle and finally are solved using the generalized differential quadrature method (GDQM). The results created from a finite element simulation illustrates a close agreement with the semi-numerical method results. Vibration characteristics of the spinning nanodisk with various boundary conditions are described based on the curves drawn by Matlab software. The outcomes show that the applied voltage, angular velocity, length scale, and nonlocal parameters, and geometrically properties of piezoelectric nanodisk have a considerable impact on the amplitude, and vibration behavior of a piezoelectric rotating cantilever nanodisk. [ABSTRACT FROM AUTHOR]

Metallic nanoparticles (NPs) are of particular interest as antimicrobial agents in water and wastewater treatment due to their broad suppressive range against bacteria, viruses, and fungi commonly found in these environments. This review explores the potential of different types of metallic NPs, including zinc oxide, gold, copper oxide, and titanium oxide, for use as effective antimicrobial agents in water and wastewater treatment. This is due to the fact that metallic NPs possess a broad suppressive range against bacteria, viruses, as well as fungus. In addition to that, NPs are becoming an increasingly popular alternative to antibiotics for treating bacterial infections. Despite the fact that most research has been focused on silver NPs because of the antibacterial qualities that are known to be associated with them, curiosity about other metallic NPs as potential antimicrobial agents has been growing. Zinc oxide, gold, copper oxide, and titanium oxide NPs are included in this category since it has been demonstrated that these elements have antibacterial properties. Inducing oxidative stress, damage to the cellular membranes, and breakdowns throughout the protein and DNA chains are some of the ways that metallic NPs can have an influence on microbial cells. The purpose of this review was to engage in an in-depth conversation about the current state of the art regarding the utilization of the most important categories of metallic NPs that are used as antimicrobial agents. Several approaches for the synthesis of metal-based NPs were reviewed, including physical and chemical methods as well as "green synthesis" approaches, which are synthesis procedures that do not involve the employment of any chemical agents. Moreover, additional pharmacokinetics, physicochemical properties, and the toxicological hazard associated with the application of silver NPs as antimicrobial agents were discussed. [Display omitted] • Metallic NPs are effective antimicrobial agents in water and wastewater treatment due to their broad suppressive range against bacteria, viruses, and fungi. • Zinc oxide, gold, copper oxide, and titanium oxide NPs have demonstrated antibacterial properties and are potential alternatives to antibiotics. • Metallic NPs can induce oxidative stress, damage to cellular membranes, and breakdowns throughout protein and DNA chains in microbial cells. • The review discusses different synthesis methods for metallic NPs and potential toxicological hazards associated with the application of silver NPs. [ABSTRACT FROM AUTHOR]

In this study, it is tried to probe the wave propagation phenomenon in an embedded functionally graded graphene oxide powder-strengthened nanocomposite curved beam exposed to different thermal loadings. In order to achieve different thermal environments, three different temperature rises including uniform temperature rise, linear temperature rise and sinusoidal temperature rise are considered. The graphene oxide powders are distributed in a polymer matrix along the curved beam thickness by regarding various patterns (i.e. X, Λ, V, O and uniform patterns). The Halpin–Tsai homogenization model is implemented to compute the effective properties of the nanocomposite structure. The kinetic relations of nanocomposite curved beam are derived by utilizing Euler-Bernoulli beam theory incorporating Hamilton's principle. The derived governing equations of nanocomposite curved beams are analytically solved to achieve the wave frequency and phase velocity values. The precision of the calculated results is verified by the published outcomes in the literature. Thereupon, a parametric investigation is performed to study the influences of different remarkable parameters like different distribution patterns of graphene oxide powders, the weight fraction of graphene oxide powders, wave number, thermal environment, elastic foundation coefficients and opening angle. • Wave propagation phenomenon of functionally graded graphene oxide powder-strengthened nanocomposite curved beam is investigated. • Five various distributions patterns are accounted for GOPs through the curved beam thickness. • The curved structure is supported on an elastic substrate. • The effect of different thermal loadings on the propagated waves is studied. • The influences of various notable parameters are examined and illustrated. [ABSTRACT FROM AUTHOR]

Application of steel pallet racks (SPRs) for storage purposes has been widely grown around the world since the age of the industrial revolution. SPRs are cold formed structures and beam-to-column connections (BCCs) used in these structures are largely responsible for the sway stability of these frames in the down-aisle direction. It is essential to understand the performance of SPR BCCs under variable circumstances. This study investigates the monotonic and cyclic behavior of SPR BCCs. The cantilever test method was used and six monotonic and six cyclic tests were conducted according to the European standard and major failure modes and moment-rotation (M-θ) behavior of the connections were identified. In order to appraise the influence of parameters, the connections were distinguished by column thickness. After investigating the original rotational stiffness value, moment resistance, ductility and failure mode of the connection, an innovative design of SPR BCC is proposed with one additional bolt in the beam end connector and monotonic testing was performed. The findings showed that the proposed connections increased the performance of SPR BCC to a larger extent. [ABSTRACT FROM AUTHOR]

This study is aimed to investigate the surface eco-protection techniques for cohesive soil slopes along the selected Guthrie Corridor Expressway (GCE) stretch by way of analyzing a new set of intelligence techniques namely neuro-bee, artificial neural network (ANN) and neuro-fuzzy. Soil erosion and mass movement which induce landslides have become one of the disasters faced in Selangor, Malaysia causing enormous loss affecting human lives, destruction of property and the environment. Establishing and maintaining slope stability using mechanical structures are costly. Hence, biotechnical slope protection offers an alternative which is not only cost effective but also aesthetically pleasing. To reach the aim of the current study, a field investigations and numerical studies were conducted and a suitable database was prepared and established. By preparing factor of safety (FOS) as a single output parameter and a combination of the most important parameters on that, the desired models have been designed based on training and test patterns. In order to evaluate and compare the prediction precision of the developed models, a series of statistical indices, such as root mean squared error (RMSE), determination coefficient (R-square) and variance account for (VAF) are calculated. Many intelligence models with the most effective parameters on the mentioned models were developed to predict FOS. Based on the simulation results and the measured indices, it was found that the proposed neuro-fuzzy model with the lowest system error and highest R-square performs better as compared to other proposed ANN and neuro-bee models. Therefore, the neuro-fuzzy can provide a new applicable model to effectively predict the FOS of the slopes due to the fact that it is able to combine the advantages of the ANN and fuzzy inference system to indicate a high prediction capacity in solving problem of slope stability. [ABSTRACT FROM AUTHOR]

Rail vehicles diagnostics is very important task since it is necessary to secure regular work of railcar and to obtain list of maintenances measures. Therefore in this study an attempt was made to analyze and model an information system for e-diagnostics for rail vehicles. The e-diagnostics system was designed based on object-oriented approach. The system should be enabled to identify and to analyze vibrations on shaft assembly. The outcomes from the system could give also conclusion about other assemblies of rail cars. The main purpose of the system us to determine the dynamic behavior and running behavior of the rail cars. Frequent analyses are main roll in early failure determining. Frequent analyses was used to dissolve vibrations on separated frequents components. • Rail vehicles diagnostics is very important task. • To secure regular work of railcar and to obtain list of maintenances measures. • To analyze and model an information system for e-diagnostics for rail vehicles. • The e-diagnostics system was designed based on object-oriented approach. • Frequent analyses was used to dissolve vibrations on separated frequents components. [ABSTRACT FROM AUTHOR]