Mitigation Efficiency Research Articles

Basic Characteristics and Vibration-Serviceability-Related Properties of Recent Footbridges in China

Abstract Purpose This study identifies basic characteristics and vibration-serviceability-related properties of recent footbridges in China. Also, it characterizes relations between vibration-serviceability-related properties and basic characteristics. Methods A database is constructed for recent footbridges in China based on systematic literature survey. For each footbridge, it collects basic information (name, function, province, location, service year), structural information (girder cross-section type, main span length, width, bridge type, girder material, deck material, first lateral and vertical natural frequencies, first lateral and vertical damping ratios), response information (crowd density, acceleration responses, mitigation measures), etc. Results Data analysis shows natural frequencies decrease with increasing bridge span. Estimation relations are proposed to quantitatively express fundamental natural frequencies and main spans in vertical and lateral directions. Damping ratios vary from 0.0015 to 0.0325, indicating the low damping capacity of the footbridges. Footbridges with non-solid cross-section are more vulnerable to human-induced excitations. Most footbridges apply mitigation measures, with mitigation efficiency from 18% to 70%. Conclusion This study provides designers with first judgements on feasibility of footbridges’ design scheme, for instance, a first estimation of natural frequency. Also, the reported information may guide them towards right directions of better design scheme, for example, by adjusting structural information.

Assessment of the Greenery Content in Suburban Multi-Family Housing Models in Poland: A Case Study of the Poznań Metropolitan Area

(1) Contemporary approaches to sustainable housing design tend to prioritize technological solutions supporting energy efficiency and climate change mitigation. On the contrary, spatial planning of housing estates does not always address all pro-ecological aspects, such as the role of greenery. This research aimed to assess the greenery content and its environmental importance in typical housing districts in the selected study area. (2) The research methodology was based on indicators reflecting the biologically active area ratio, the length of communication routes lined with trees, the tree number per area unit, the tree canopy, and the environmental benefits delivered by the trees. The above indicators allowed us to compare selected models of suburban residential districts typical of specific timeframes. (3) The results indicated that the greenery content and its environmental benefits in suburban districts are decreasing in the study area. Another finding concerned the importance of selecting tree species for their ability to develop a canopy and provide ecosystem services. (4) The proposed methodology, based on inter-related indicators, validly compared the greenery content in the analyzed districts, giving it application value. The problems observed contributed to the proposal of a revision of Poland’s planning practices. Local zoning plans could include streetscape standards, indicating paving solutions and plantings to improve the situation.

What-if nature-based storm buffers on mitigating coastal erosion

Creating ecosystem buffers in intertidal zones, such as seagrass meadows, has gained increasing attention as a nature-based solution for mitigating storm-driven coastal erosion. This study presents what-if scenarios using an integrated model framework to determine the effectiveness and strategies for planting seagrass to reduce coastal erosion. The framework comprises two levels of simulation packages. The first level is a regional-scale coupled hydrodynamic model that simulates the processes of a specific storm and provides boundary forces for the morphodynamic model XBeach to apply at the next level, which simulates nearshore morphological evolution. The framework is applied to the open coast of Norderney in the German Bight of the North Sea. We demonstrate that optimising the location and size of seagrass meadows is crucial to increase the efficiency of onshore sediment erosion mitigation. For a specific depth range, depending on the storm's intensity, the most significant reduction in erosion may not be achieved by starting the meadow at the depth that permits the largest meadow size. To maintain a significant coastal protection effect, seagrass density and stem height should be considered together, ensuring erosion reduction by at least 80 % compared to the unprotected coast. This study provides valuable insights for the design and implementation of seagrass transplantation as a nature-based solution, highlighting the importance of considering location, size, density, and stem height when using seagrass meadows for coastal protection.

Recent trends on energy-efficient solar dryers for food and agricultural products drying: a review

AbstractThe energy efficiency enhancement of solar dryers has attracted the attention of researchers worldwide because of the need for energy storage in solar drying applications, which arises primarily from the irregular nature of solar energy that leads to improper drying which will reduce the quality of the products being dried. This work comprehensively reviews the state-of-the-art research carried out on solar dryers for energy efficiency enhancement using various alternative strategies, including hybrid solar dryers that use auxiliary heating sources, such as electric heaters or biomass heaters, solar-assisted heat pump dryer, use of desiccant materials, and heat storage systems that use both sensible and latent heat storage. The advent of phase change materials (PCM), such as thermally and chemically stable PCMs, for long-term storage, bio-degradable and bio-compatible PCM materials to alleviate the negative environmental impact of conventional PCMs is also presented. The performance parameters considered for evaluating dryers include the maximum temperature attained inside the drying chamber, drying time and efficiency, specific moisture extraction rate (SMER), energy and exergy efficiency and CO2 mitigation effect. The factors considered to analyze the PCMs application in solar dryers include cost and sustainability of PCMs, and both energy and exergy analyses of dryers using PCMs. The gaps in current knowledge and future scope for further improvement of solar dryers are also elucidated. Graphical abstract

Metagenomics reveals the variations in functional metabolism associated with greenhouse gas emissions during legume-vegetable rotation process

Legume-based rotation is commonly recognized for its mitigation efficiency of greenhouse gas (GHG) emissions. However, variations in GHG emission-associated metabolic functions during the legume-vegetable rotation process remain largely uncharacterized. Accordingly, a soybean-radish rotation field experiment was designed to clarify the responses of microbial communities and their GHG emission-associated functional metabolism through metagenomics. The results showed that the contents of soil organic carbon and total phosphorus significantly decreased during the soybean-radish process (P < 0.05), while soil total potassium content and bacterial richness and diversity significantly increased (P < 0.05). Moreover, the predominant bacterial phyla varied, with a decrease in the relative abundance of Proteobacteria and an increase in the relative abundance of Acidobacteria, Gemmatimonadetes, and Chloroflexi. Metagenomics clarified that bacterial carbohydrate metabolism substantially increased during the rotation process, whereas formaldehyde assimilation, methanogenesis, nitrification, and dissimilatory nitrate reduction decreased (P < 0.05). Specifically, the expression of phosphate acetyltransferase (functional methanogenesis gene, pta) and nitrate reductase gamma subunit (functional dissimilatory nitrate reduction gene, narI) was inhibited, indicating of low methane production and nitrogen metabolism. Additionally, the partial least squares path model revealed that the Shannon diversity index was negatively correlated with methane and nitrogen metabolism (P < 0.01), further demonstrating that the response of the soil bacterial microbiome responses are closely linked with GHG-associated metabolism during the soybean-radish rotation process. Collectively, our findings shed light on the responses of soil microbial communities to functional metabolism associated with GHG emissions and provide important insights to mitigate GHG emissions during the rotational cropping of legumes and vegetables.

Evaluation of active leeward side air-blowing layout on the lateral aerodynamic performance of high-speed trains in crosswinds environment: Sustainable and safe operation strategy

The lateral aerodynamic forces experienced by high-speed trains operating in crosswind environments affect trains' operating safety significantly. This paper used the Improved Detached Eddy Simulation (IDDES) method based on the Shear Stress Transport (SST) k-ω turbulence model to explore the mitigating effect of air-blowing at the leeward side of the train on the train's lateral aerodynamic forces. Different air-blowing positions and speeds were considered. The results indicate that the best mitigating effect can be achieved when simultaneously blowing air at the head, middle, and tail cars; in addition, when blowing air at the speed of 0.3 times of the resultant velocity, the rolling moment of the three cars reduced by 7.71%, 7.25%, and 25.46% respectively. Finally, the assessment of the mitigation efficiency was displayed to discuss the trade-off of rolling moment reduction and energy utilization rate for air-blowing. The research gives an insight into increasing the stability and safety of trains in crosswind based on active control, which can improve the safe operation threshold of trains.

A simple but effective method for the enrichment of Al in red mud waste

This study proposes transforming red mud, an abundant byproduct from the aluminum industry, into minerals using Na2CO3 activation for efficient water leaching. It was aimed at breaking down the rigid Al-Si network structure. The investigation compares the effects of sodium salts, with Na2CO3 achieving an 88.90 % aluminum leaching rate crucial for activating katoite and cancrinite in red mud. Using XRD, FT-IR, SEM-EDS, in situ hot-stage microscopy, FactSage, and Material Flow Analysis, the study explores changes in Na2CO3-loaded red mud, elucidating its role in converting aluminum-bearing minerals into water-soluble aluminates at a low temperature of 900 °C for an optimum activation duration of 90 min, with a preferred loading of 32 % Na2CO3. Introducing a new cyclic aluminum extraction method from red mud, utilizing sodium salts, especially Na2CO3, the study optimizes the activation process through a comprehensive exploration of thermal and mineral transformation behaviors. Quantitative analysis of Na and Al elements ensures successful recovery and cyclic utilization of Na2CO3, maintaining aluminum extraction efficiency above 82 % after six cycles. This economically feasible closed-loop system aligns with principles of industrial efficiency and climate change mitigation. Na2CO3, acting as an activator and a carbon sink, showcases significant potential for sustainable aluminum production.

Exploring the dynamic mechanism of water wetting induced corrosion on differently pre-wetted surfaces in oil–water flows

Water wetting induced corrosion is the core issue for uncovering the corrosion mechanism in multiphase flow environments, relevant to many industrial applications. Here, we experimentally investigated the dynamic failure of an oil film attached on the pre-wetted model surfaces by the electrochemical current detection using an “Alternate Wetting Cell” and the direct visualization of near-wall fluid states. The oil pre-wetted surface performed a superior corrosion mitigation efficiency, exhibiting a protective oil film with a duration time at least 5 times longer than the water pre-wetted surface. It confirms that the oil film rupture is a combined process of the local penetration and pinning of micro-droplets and the phase redistribution of the near-wall fluids. Corrosion finally initiates and propagates on the surface once the droplets pin there or damage the oil film. The result suggests new control strategies for materials corrosion in complex systems by surface modification and fluid management.

An open web-based GIS service for biomass data in Finland

Reliable, up-to-date biomass data are needed for climate change mitigation and resource efficiency. Therefore, a calculation and reporting tool with thematic maps and data was developed. A free web-tool, Biomass Atlas, collects the spatial distribution of biomasses in Finland. Over 300 data layers present land use, cultivation, residual biomasses from forest, crop production, animal husbandry, municipalities, and industry at 1 km2 spatial resolution. The service enables calculations of biomass amount in a defined geographical area of interest and examining the opportunities and restrictions to utilise biomasses. The service was evaluated with six test-users in laboratory tests and 20 voluntary pilot test-users. Biomass Atlas shows the regional potential of biomaterials, fertilizer products, and renewable energy, as well as potential targets for utilized, recyclable biomass. Other possible uses include monitoring plant cover on fields and assessing land use diversity. Application enables users with no experience in GIS or biomass assessments to analyse biomass resources, produce maps and data summaries for decision making.

An analytical study on the effect of different photovoltaic technologies on enviro-economic parameter and energy metrics of active solar desalting unit

The enviro-economic and energy metrics analyses of the solar system by incorporating different photovoltaic technologies are required to fulfill the sustainable development goal of the United Nations. However, the effect of different photovoltaic technologies on the solar distillation system has not been informed by any of the researchers to date. This research gap has been explored in this study. The present manuscript is an endeavour to explore the best photovoltaic technology aimed at a single-slope solar desalting unit comprised of N identical photovoltaic thermal flat-plate-collectors. Data regarding all four weather conditions for a year for New Delhi's climate have been procured from the Indian Meteorological Department situated in the western part of India. Fundamental equations along with input data have been provided to a computational code developed in MATLAB for the estimation of various performance parameters. Concludingly, the energy payback time is minimum (1.64 years) for the case of copper indium gallium selenide photovoltaic technology, however, maximum values of life cycle conversion efficiency and net CO2 mitigation are respectively 0.171 and 199.10 tons of CO2 for the case of crystalline silicon photovoltaic technology. The carbon credit is also found to be a maximum (15269.25 US$) for crystalline silicon photovoltaic technology.

Building a sustainable future: evaluating eco-friendly materials for energy efficiency and climate change mitigation

ABSTRACT Rapid population growth has increased housing demand. This demand was mainly addressed using conventional and unsustainable construction materials, which raised concerns about intensifying global warming. Economically challenged communities lacking access to cooling systems are more vulnerable to climate change effects. This research proposes strategies to address future climate change challenges, assessing the energy efficiency of a lab-developed eco-friendly construction material. A TRNSYS-based model was used in this study to evaluate four materials: rammed earth, hemp-lime bricks, DOUM fibre-stabilized material with quicklime, and cinder blocks in a real-scale building. Prior to the energy assessment, GenOpt software was used to ensure efficient building design. Optimizing the building's envelope can reduce annual thermal loads by up to 52%. The DOUM-clay brick house, with high thermal mass, exhibits significant potential. In comparison, the cooling loads of the cinder block, the rammed earth, and the hemp clay houses are 24.8%, 11.9%, and 9.2% lower, respectively. Additionally, the study considers the impact of climate change on buildings in a hot, semi-arid climate. The findings reveal a 20.3% lower thermal load for the lab-developed brick house compared to the cinder block house. The study also anticipates a reduction in natural ventilation’s potential in the future.

Improvement energy performance for GHG mitigation - a case of FPSO vessel platform in Oil &amp; Gas offshore production

This study offers an in-depth review of specific facets of the oil and gas industry, emphasizing the role of Floating Production, Storage, and Offloading (FPSO) vessels. It delves into diverse topics, highlighting potential opportunities, a solid research methodology for emissions quantification, and the pivotal challenge of reducing GHG emissions. Among the multitude of opportunities analyzed within the industry's value chain, the upstream sector - encompassing both exploration and production of oil and natural gas - receives considerable focus. This sector can be further divided into key segments characterized by high energy consumption and consequent significant emissions. Notably, the combustion of natural gas for power generation stands out, contributing a substantial 68% of CO2 emissions at related facilities. This process is a primary target for mitigation and energy efficiency enhancements. The intricate interplay between energy generation and CO2 emissions stands at the forefront of current research, emphasizing the need for improving vessel energy efficiency. This paper employs a case-based methodology, evaluating the effectiveness of energy efficiency measures within an FPSO setting and their resulting impact on GHG emissions. Central to this inquiry is a detailed examination of the FPSO Fluminense, strategically located within Brazil's Campos Basin, with the study meticulously examining the relationship between advancements in energy efficiency and emission reductions. While translating these insights into practical applications poses challenges, the momentum generated by rigorous research, combined with policy recommendations addressing GHG emissions in the oil sector, can indeed chart a path toward a more robust, sustainable, and integrated energy future.

GABA Supplementation, Increased Heart-Rate Variability, Emotional Response, Sleep Efficiency and Reduced Depression in Sedentary Overweight Women Undergoing Physical Exercise: Placebo-Controlled, Randomized Clinical Trial

Gamma-aminobutyric acid (GABA) serves as a pivotal neurotransmitter implicated in the pathogenesis of stress, anxiety, sleep-related disorders, and heart rate (HR) reactions. Heart-rate variability (HRV), modulated by the sympathetic and parasympathetic branches of the autonomic nervous system (ANS), offers insights into cardiac autonomic control and cardiovascular well-being. The present study aimed to explore the impact of GABA supplementation on emotional metrics, sleep quality, and HRV in sedentary women with overweight or obesity partaking in physical exercise. A randomized, double-blind, placebo-controlled clinical trial was undertaken involving 30 sedentary women with overweight or obesity. Volunteers were assigned randomly to two groups: the intervention group receiving GABA (200 mg) once daily for a total of 90 supplementation doses, and the placebo group. Both groups engaged in physical exercise, while the supplementation regimen spanned 90 days. Assessments were conducted at three intervals: baseline (T0), midway through the study (T45), and study culmination (T90). Following 90 days of GABA supplementation, the intervention group demonstrated enhancements in habitual sleep efficiency, as indicated by reductions in Pittsburgh Sleep Quality Index (PSQI) scores. Moreover, an improved emotional response was observed, characterized by diminished negative affect. GABA supplementation yielded ameliorations in depression scores as per the Depression, Anxiety, and Stress Scale (DASS-21). Notably, an augmented HRV was noted, attributed to heightened parasympathetic autonomic nervous system predominance. GABA supplementation elicited noteworthy enhancements in heart rate variability, emotional response, depression mitigation, and sleep efficiency following a 90-day supplementation.

Developing a Cybersecurity Training Environment through the Integration of OpenAI and AWS

Cybersecurity is a critical concern in today’s digital age, where organizations face an ever-evolving cyber threat landscape. This study explores the potential of leveraging artificial intelligence and Amazon Web Services to improve cybersecurity practices. Combining the capabilities of OpenAI’s GPT-3 and DALL-E models with Amazon Web Services infrastructure aims to improve threat detection, generate high-quality synthetic training data, and optimize resource utilization. This work begins by demonstrating the ability of artificial intelligence to create synthetic cybersecurity data that simulates real-world threats. These data are essential for training threat detection systems and strengthening an organization’s resilience against cyberattacks. While our research shows the promising potential of artificial intelligence and Amazon Web Services in cybersecurity, it is essential to recognize the limitations. Continued research and refinement of AI models are needed to address increasingly sophisticated threats. Additionally, ethical and privacy considerations must be addressed when employing AI in cybersecurity practices. The results support the notion that this collaboration can revolutionize how organizations address cyber challenges, delivering greater efficiency, speed, and accuracy in threat detection and mitigation.

Mitigation of multiple pesticide residues in green bell pepper using natural extracts as an emerging trend in pesticide decontamination using GC–MS/MS

AbstractThe main objective of this work is to assess the effect of natural extracts and its characterization for the mitigation of multiple pesticide residues in green bell pepper. In this study, four plant extracts such as Acacia concinna, Albizia amara, Tamarindus indica, and Azadirachta indica have been used to mitigate the six pesticides present in green bell pepper and its phytochemical constituents were analyzed using gas chromatography coupled to triple quadrupole tandem mass spectrometry (GC–MS/MS). In addition to that, the method for the quantification of six pesticide residues in green bell pepper using GC–MS/MS was validated according to SANTE/11312/2021 guidelines. The extracts of Acacia concinna, Albizia amara, Tamarindus indica, and Azadirachta indica were showed effective mitigation for selected pesticides. The phytochemical compounds present in plant extracts were correlated with its effect on the mitigation of multiple pesticide residues. The T. indica showed better pesticide mitigation efficiency when compared to A. indica, A. amara, and A. concinna, respectively. The plant extracts showed higher mitigation efficiency for organophosphorous pesticides than the synthetic pyrethroids. The nutritional and sensorial properties of green bell pepper were highly retained after pesticide decontamination using plant extracts. The results of this work indicated the application of plant extracts for the mitigation of multiple pesticides in green bell pepper by household and commercial processing units. This study addressed the balance between food safety and food quality.Practical ApplicationsPesticide contamination in vegetables is one of the major global food safety issues and it poses potent threat to human health. Pesticide decontamination is always a challenging task due to the unpredictability of types and levels of pesticides and the presences of multiple pesticides in contaminated vegetables. Washing of vegetables with water is the common procedure followed by both household and commercial units. However, washing of vegetables only with water is not enough to reduce the multiple pesticides residues to safe levels. The washing of vegetables with chemical solutions and other thermal and non‐thermal processing could result in toxic byproduct formation based on the types of pesticides present in contaminated sample. Hence, in this study, the plant extracts were characterized for its efficiency on the mitigation of multiple pesticide residues in vegetables has been analyzed by Gas Chromatography—Triple Quadrupole Tandem Mass Spectrometry and the method has been validated according to SANTE/11312/2021 guidelines. The phytochemical compounds of the plant extracts could be correlated with the effective multiple pesticide decontamination efficiency and the plant extracts were found to retain the physicochemical properties of vegetables during washing. The results of this study showed that the selected plant extracts could enhance the food safety without compromising food quality. The results of this study could be useful for the formulation of vegetables cleaning solutions for the effective mitigation of multiple pesticide residues.

Assessment of “Rubber wheel hoe weeder” for weeding efficiency in mustard crops and drudgery mitigation of farm women

Assessment of “Rubber wheel hoe weeder” for weeding efficiency in mustard crops and drudgery mitigation of farm women

Industrial Energy Efficiency and Climate Change Mitigation in Smart Cities: A Comprehensive Review

Industrial Energy Efficiency and Climate Change Mitigation in Smart Cities: A Comprehensive Review

Numerical study on the blast mitigation effect of an inner-grooved straight tube

A series of numerical simulations were conducted to clarify the shock–structure interaction inside an inner-grooved straight tube and the mitigation effect of the groove structure on the expansion of the blast wave at the exit. The results showed that the periodic grooves of the groove structure generate multiple reflected shock waves. Each time a shock wave reaches a groove, some of the shock wave and gas flow behind it propagates directly through the downstream groove, and the rest is reflected to the upstream groove. This splitting decreases the shock wave strength inside the tube. To clarify the blast mitigation effect of the configuration of the groove structure, parametric studies were conducted that changed the height and interval of the periodic grooves. The flow characteristics inside the tube were analyzed to understand the blast mitigation efficiency of the groove structure. The groove height had a significant impact on the blast mitigation efficiency, and the optimal interval for maximum blast mitigation efficiency depended on the groove height. The total energy release rate from the tube exit is a characteristic value of the blast wave strength at the exit, and it can be used to scale the blast wave strength outside.

Big Data and Neural Networks in Smart Grid - Part 1: The Impact of Measurement Differences on the Performance of Neural Network Identification Methodologies of Overhead Low-Voltage Broadband over Power Lines Networks

Until now, the neural network identification methodology for the branch number identification (NNIM-BNI) and the neural network identification methodology for the distribution line and branch line length approximation (NNIM-LLA) have approximated the number of branches and the distribution line and branch line lengths given the theoretical channel attenuation behavior of the examined overhead low-voltage broadband over powerlines (OV LV BPL) topologies [1], [2]. The impact of measurement differences that follow continuous uniform distribution (CUDs) of different intensities on the performance of NNIM-BNI and NNIM-LLA is assessed in this paper. The countermeasure of the application of OV LV BPL topology databases of higher accuracy is here investigated in the case of NNIM-LLA. The strong inherent mitigation efficiency of NNIM-BNI and NNIM-LLA against CUD measurement differences and especially against those of low intensities is the key finding of this paper. The other two findings that are going to be discussed in this paper are: (i) The dependence of the approximation Root-Mean-Square Deviation (RMSD) stability of NNIM-BNI and NNIM-LLA on the applied default operation settings; and (ii) the proposal of more elaborate countermeasure techniques from the literature against CUD measurement differences aiming at improving NNIM-LLA approximations.

Vibration damping by periodic additive acoustic black holes

Embedded acoustic black holes (ABHs) have demonstrated significant efficiency in vibration mitigation. However, their practical application is limited due to their inherent low strength. To address this issue, this paper introduces an alternative approach of additive ABHs, which are periodically mounted on the host structure to simultaneously enhance structural rigidity and damping effects. The Gaussian expansion method (GEM) is employed to model the ABH beam and base beam within the framework of Timoshenko beam theory. The coupling between the two substructures is achieved using the nullspace method (NSM) based on the interface coupling condition. Additionally, the wave and Rayleigh–Ritz method (WRRM) is utilized to handle the Bloch-Floquet periodic boundary conditions. The complex dispersion curves are obtained using the k(ω) method, where the imaginary part represents the attenuating waves in space. The accuracy of the proposed model is validated against finite element simulations for the unit cell modes and dispersion curves. The results indicate that local resonance dominates the behavior, overshadowing the Bragg scattering effect. Furthermore, the inclusion of a damping layer results in a strong damping effect across a wide frequency band. Parametric studies reveal that larger lattice constant and increased uniform portion thickness of the ABH contribute to better damping performance, albeit with an associated increase in the added mass of the ABH component. Finally, the damping capability of finite periodic beams with 5 cells is investigated, assessing modal loss factor (MLF), transmissibility, and forced vibration shapes. The findings demonstrate that the proposed additive ABH approach opens up new possibilities for engineering applications.