Loading Time Research Articles

Justification of fire protection measures in the NPP control room using CFD fire modeling

Introduction. The present paper provides justification of fire safety measures to protect systems of the main control room of NPP using computational fluid dynamics fire modeling.Aim. To develop fire protection measures for systems of the NPP control room using computational fluid dynamics model.Materials and methods. The study involved analysis into purpose and application scope of various methods for modeling dynamics of development and spread of fire hazards. The application of the computational fluid dynamics fire modeling for multifunctional premises was considered.Results. Following the analysis of different methods for modeling the dynamics of development and spread of fire hazards, the present paper introduces the potential of using various methods of fire modeling in the evaluation of fire hazards for main control room. The obtained computations show that the temperature at the reinforcement site remains below the critical value in the most dangerous fire development scenarios like ventilation controlled fire. Moreover, fire hazards fail to spread through the walls of an uninsulated room within three hours at any value of fire load in main control room.Conclusions. The study revealed a potential for using computational fluid dynamics fire modeling for evaluating fire hazards in various buildings and premises, as well as for justifying the sufficiency of fire resistance requirements established for building structures. This regularity is obtained under conditions of preventing the spread of fire beyond the fire zone within the estimated burnout time of the entire fire load. The results received for this particular type of premises (cable floor) indicate that the designed fire resistance of the barriers separating safety system premises and normal operation premises guarantees non-proliferation of fire. The obtained regularities can be used in the development/revision of regulatory documents on fire safety at operating NPPs and NPPs under construction

Glass-Forming Ability, Mechanical Properties, and Energetic Characteristics of ZrCuNiAlNbHfY Bulk Metallic Glasses.

The effects of partially substituting Al for Cu in Zr59.62Cu18.4-xNi12Al6+xNb3Hf0.78Y0.2 (x = 0, 2, 4, 6, 8 at.%) bulk metallic glasses (BMGs) on their glass-forming ability (GFA), quasi-static and dynamic mechanical properties, and energy characteristics were investigated. The results showed that an appropriate substitution of Al for Cu can improve GFA and reach a critical casting size up to 10 mm. Additionally, with Al replacement of Cu, the change in the distribution and content of free volume inside the BMGs was the main reason for the quasi-static compression plasticity. In contrast, the BMGs exhibited no plasticity during dynamic compression and high-speed impact, owing to the short loading time and thermal softening effect. In terms of energy characteristics, all alloys have a high combustion enthalpy. And on the surface of the fragments collected from impact, the active elements Zr, Al, and Nb reacted because of the adiabatic temperature rise. Further, x = 4 at.% Zr-based BMG with its superior overall performance could penetrate a 6 mm Q235 plate at a speed of 1038 m/s, combining excellent mechanical properties and energy characteristics. This study contributes to the development of Zr-based BMGs as novel energetic structural materials.

Morphology characteristics of filler particles and their effects on the low–temperature cracking behavior of asphalt mastics

The article concerned on particle morphology of mineral filler and its impact on mastic cracking property at low temperatures. Limestone and granite fillers with four-sized groups were prepared and further investigated using a simplex-centroid experimental design. The particle morphologies of each filler were captured using a digital image processing. By applying bending beam rheometer tests, mastic cracking behavior was investigated at low temperatures. Results show that compared with granite filler, each limestone filler shows less regular contour shape (except l1), less abundant angularity (except l1, l2, l5 and l17) and surface texture when performed by a simplex-centroid experimental design. The established fractional derivative Burgers model considering creep damage can effectively describe mastic cracking behavior at low temperatures. Composite fractal dimension is the decisively relevant factor with mastic relaxation behavior. Moreover, mastic creep damage is obviously affected by composite morphology characteristics and filler lithology with increasing loading time. All the results are instructive to inform researches of the selection of mineral filler with appropriate particle morphology that will produce asphalt materials with desired performance.

Performance measurement implementation on the smart fisheries village website using pagespeed insight

Websites have become the primary way organizations and individuals to communicate, provide information, and offer daily services. The purpose of creating the Smart Fisheries Village (SFV) website was to enhance the performance and quality of the user experience by measuring and optimizing image sizes using Google's tools, specifically Google PageSpeed Insight. We monitored and analyzed the implementation performance to ensure faster loading times without compromising visual quality. The implementation results showed significant improvements in the SFV loading speed, leading to a more satisfactory user experience. To identify images that slow website loading, we used data from PageSpeed Insight. After implementing improvements, we distributed a questionnaire to users to evaluate the development results. The results of the questionnaire revealed a significant increase in user satisfaction with the loading speed and quality of the user experience of the Bangsring Smart Fisheries Village (SFV) website. These findings provide valuable information for the continued development and optimization of website performance in the future. Therefore, this research makes a valuable contribution to improving the performance and user experience of the Bangsring Smart Fisheries Village (SFV) website.

Research on the low-frequency fatigue behavior of NEPE solid composite propellant based on fractional derivative constitutive model

The long-term fatigue loading history from offshore vibration environment will cause microdamage and affect the mechanical properties of NEPE solid propellant grains. The paper investigates the evolution law of microdamage through constant-strain-amplitude fatigue tests, and proposes an improved fractional derivative constitutive model for effectively predicting the low-frequency fatigue behavior of NEPE solid propellant based on the experimental phenomena. The evolution law of microdamage is negative power functional with the loading time and exponential with the maximum loading strain during the fatigue loading process. The stress-softening behavior, the Mullins effect, and the accumulation of residual strain are observed, as characteristics of low-frequency fatigue behavior. The theoretical modeling of the stress-softening behavior and the Mullins effect is proven to be significant for effectively predicting the low-frequency fatigue behavior by the improved fractional derivative constitutive model, while strain-modfication is also necessary for eliminating the influence of residual strain. The fatigue damage in solid propellant grains cannot be neglected when assessing the structural integrity of a solid propellant grain which has experienced long-term transportation or offshore storage.

On the economics of co-opting in energy sector

The purpose of the work is to formulate the main provisions of the co-opting economy and detail them using the case method in the field of energy. Elizabeth Watkins and David Stark from Columbia University (USA) put forward the concept of Möbius organizational forms. Unlike traditional forms in business, Möbius forms do not Make, Buy or Cooperate, they Co-opt assets that do not belong to them. In 2019, the author of this work proposed the term "paraphernalia", which reflects the essence of the theory, but the name is more suitable for the Global Informality Project online encyclopedia, in which it was published. The co-opting economics is a social science about the production, distribution, exchange and consumption of goods and services with non-violent, but non-cooperative appropriation of assets belonging to others to satisfy one's own needs. The original formula of the co-opting economy is: money-commodity-money with a dash and an additional commodity (good) received for free, which is produced with the help of assets belonging to other owners. Theoretical studies were carried out using the case method. The effect of the co-opting economy is demonstrated on the example of the Sukha Balka mine (Kryvyi Rih). The mine has shafts hoists. In the process of moving loads, hoist generate electricity that is recovered and fed back into the network. The author introduces the conditional category "Mechanics", whose asset is mine hoist, and the category "Energeticians", whose asset is power distribution networks. The additional energy resource received by the Mechanics flows through the network to the Energeticians and becomes their property. There is a co-optation of assets that do not belong to Energeticians, with the receipt of a product that they use to meet their own needs. Such a virtual power plant does not belong to any energy company, but helps it to overcome the shortage of electricity during times of maximum load. Here, too, energy companies adhere to the economy of co-optation, because the generating assets they use are not their property. By adopting legislative acts on the introduction of the active consumer category, the state indirectly contributes to the development of the co-optation economy.

Strength degradation and damage mechanism of TA1 titanium alloy clinched joints under fatigue loading

A digital model for the strength degradation of titanium alloy clinched joints was established using strength degradation tests and a fatigue cumulative damage model. This model aims to investigate the strength degradation law and fatigue damage failure mechanism of titanium alloy clinched joints under fatigue loading. Fractured test specimens were scanned to analyse the fatigue damage failure mechanism by examining the evolution of fracture morphology under varying fatigue cyclic loading times. The results demonstrate that the power index degradation model accurately predicts the strength degradation of titanium alloy clinched joints. As the number of fatigue loading cycles increases, cleavage features emerge alongside fatigue cracks, leading to a gradual reduction in joint strength. Ultimately, the strength degradation power index model for titanium alloy clinched joints is verified by the test to have high accuracy in predicting residual strength.

Influence of Mechanical Loading on the Process of Tribochemical Action on Physicochemical and Biopharmaceutical Properties of Substances, Using Lacosamide as an Example: From Micronisation to Mechanical Activation.

Many physical and chemical properties of solids, such as strength, plasticity, dispersibility, solubility and dissolution are determined by defects in the crystal structure. The aim of this work is to study in situ dynamic, dispersion, chemical, biological and surface properties of lacosamide powder after a complete cycle of mechanical loading by laser scattering, electron microscopy, FR-IR and biopharmaceutical approaches. The SLS method demonstrated the spontaneous tendency toward surface-energy reduction due to aggregation during micronisation. DLS analysis showed conformational changes of colloidal particles as supramolecular complexes depending on the loading time on the solid. SEM analysis demonstrated the conglomeration of needle-like lacosamide particles after 60 min of milling time and the transition to a glassy state with isotropy of properties by the end of the tribochemistry cycle. The following dynamic properties of lacosamide were established: elastic and plastic deformation boundaries, region of inhomogeneous deformation and fracture point. The ratio of dissolution-rate constants in water of samples before and after a full cycle of loading was 2.4. The lacosamide sample, which underwent a full cycle of mechanical loading, showed improved kinetics of API release via analysis of dissolution profiles in 0.1 M HCl medium. The observed activation-energy values of the cell-death biosensor process in aqueous solutions of the lacosamide samples before and after the complete tribochemical cycle were 207 kJmol-1 and 145 kJmol-1, respectively. The equilibrium time of dissolution and activation of cell-biosensor death corresponding to 20 min of mechanical loading on a solid was determined. The current study may have important practical significance for the transformation and management of the properties of drug substances in solid form and in solutions and for increasing the strength of drug matrices by pre-strain hardening via structural rearrangements during mechanical loading.

What controls the magma production rate along the Walvis Ridge, South Atlantic?

The Walvis Ridge is a volcanic chain with the most pronounced topographic anomaly in the South Atlantic. This study analyzes the factors influencing magma production rates along the ridge to provide insights into hotspot-lithosphere interactions. With the sub-lithospheric gravity effect excluded, we determine the crustal thickness in the South Atlantic via gravity inversion. By subtracting the age-averaged crustal thickness, we isolate the excess crustal thickness attributable to ridge magmatism and calculate the magma generation rate along the Walvis Ridge over the past 80 Ma. Our results reveal a relatively lower magma production rate in the Walvis Ridge (peaking at ∼2.5 m3/s) compared to other major hotspot tracks (e.g. Hawaii-Emperor seamount chain, Ninetyeast Ridge, or Deccan-Reunion hotspot). Furthermore, variations in magma production rate show a strong inverse correlation with lithospheric thickness (or crustal age) at the time of loading but no significant correlation with spreading rate. Extensively distributed fracture zones in the lithosphere also promote magma production during the period of ∼70–40 Ma. Together with previously identified spreading-type magmatism in the northeast Walvis Ridge, we infer that external tectonic factors, other than hotspot-related factors, play a crucial role in magma production rate across the entire Walvis Ridge.

Improving Scrum Methodology Management using the Kano Model

The software development process requires the use of methodologies and methods that contribute to its construction in a way that ensures the achievement of its required quality. The Scrum methodology is one of these methodologies. Still, this methodology needs a mechanism to ensure a clear structure for its organization. Therefore, the goal of this paper is to improve the work of this methodology, as the Scrum methodology was integrated with the Kano model to work as an organized framework that facilitates developers to use it easily by integrating the Scrum methodology with the Kano model, which strategically aims to enhance software development practices and enhance the effectiveness of Scrum. Through practicality in a real-world scenario, this framework demonstrates exceptional stability and clarity in alignment with system requirements. The main purpose of this study is to integrate the Scrum methodology with the Kano model to improve the performance of the Scrum methodology, clarify requirements, reduce the constant change in requirements, facilitate meetings, and organize teams and their work that is directly related to system requirements The proposed framework was applied to a case study involving an e-commerce site evaluated using assessment tools, including GTMetrix, PageSpeed Insights, and Pingdom, which collectively highlights the system's powerful optimization potential, displaying excellent results in performance, structural audits, and load times. This research measures the effectiveness of the framework in improving the software development process, which leads to the development of a high-performance, user-centric e-commerce platform the results confirm that this approach can contribute significantly to the evolving landscape of agile methodologies and software development.

SDS and TX-100 performance in removing Cd ion from contaminated sand in flushing column

In this study, contaminated sand by cadmium (Cd2+) ion was cleansed by surfactant foam in a flushing column. The ability to remove Cd2+ ion on the sand surface influenced by the surfactant's properties. The Sodium dodecyl sulfate (SDS) as an anionic surfactant was compared with Triton X-100 (TX-100) non anionic surfactant in their ability to remove the metal ion on the sand surface in the flushing column. The loading time, surfactant concentration, and flow rate of the surfactant were then investigated to confirm the charging effect of surfactant in the ability to remove metal ions. The results show that SDS has a higher ability than TX-100 to remove the Cd2+ ion on the sand surface. The optimal removal efficiency by SDS was 52 %, and TX 100 was 47 %. The loading time impacted surfactant interaction with metal ions in the column, showing that a longer loading time will increase the removal efficiency. Increased concentration of surfactants and more prolonged initial flushing tend to remove higher metal ions, indicating that the residual metal ion was flushing out on the first four pore volume removals. Flushing in a column with foam by anionic surfactant shows a higher ability to remove metal ions on the sand surface.

Preparation and characterization of cellulose-chitosan/β-FeOOH composite hydrogels for adsorption and photocatalytic degradation of methyl orange

Biopolymer-based hydrogels have received great attention in wastewater treatment due to their excellent properties, e.g., high adsorption capacity, fast kinetics, reusability and ease of operation. In the present work, cellulose-chitosan/β-FeOOH composite hydrogels were prepared via co-dissolution and regeneration process as well as hydrothermal in situ synthesis of β-FeOOH. Effect of β-FeOOH loading on the properties of the composite hydrogels and the removal efficiency of methyl orange (MO) was investigated. Results showed that β-FeOOH was uniformly loaded onto the hydrogel framework, and the nanoporous structure of composite hydrogels could increase not only the effective contact area between β-FeOOH and the pollutants but also the active sites. Moreover, the increased β-FeOOH loading led to the enhanced MO removal rate under light conditions. When the loading time was extended from 6 h to 9 h, the MO removal rate increased by 21%, which can be mainly due to the photocatalytic degradation. In addition, MO removal rate reached 97.75% within 40 min under optimal conditions and attained 80.81% after five repetitions. The trapping experiment and EPR results indicated that the main active species were hydrogel radicals and holes. Consequently, this work provides an effective preparation approach for cellulose-chitosan/β-FeOOH composite hydrogel with high adsorption and photocatalytic degradation, which would hold great promise for wastewater treatment applications.

Data-driven forecasting of FOWT dynamics and load time series using lidar inflow measurements

This study focuses on forecasting the fairlead tension and floater dynamics time series of floating offshore wind turbines (FOWTs) using a data-driven approach that incorporates onboard sensor measurements and lidar inflow data. Sensors on FOWTs can provide data on turbine dynamics, such as rotational and translational movements, and load metrics like mooring line loads. However, these sensors are limited to current state measurements and do not provide future signal projections. In this research, we investigate a data-driven forecasting methodology using a simulated dataset. This dataset encompasses FOWT responses to diverse environmental conditions and the associated lidar measurements. Utilizing a Long Short-Term Memory (LSTM) sequence-to-sequence model, this study forecasts the time series of fairlead tension, surge, and pitch for forecasting horizons of 20, 40, and 60 seconds, considering lidar ranges from 100m to 500m. The performance of these forecasting models is benchmarked against a simple persistence model. The results indicate that incorporating lidar inflow measurements significantly improves the forecasts of fairlead tensions and platform motions. The enhancement for pitch motion forecasts is observed across all forecasting horizons. For fairlead tension and surge motion, the enhancement is observed for the longer horizons of 40s and 60s. These findings underscore the value of lidar data in accurate forecasting and emphasize the need to account for the interplay between lidar range, wind speed, and forecasting horizon to achieve optimal forecast accuracy.

Integrated catalytic approach for advanced biofuel production from renewable ABE fermentation

This study focuses on advancing the production of sustainable aviation biofuels by employing a one-pot integrated catalytic approach to convert Clostridium beijerinckii strain SR-44 ABE fermentation products into higher-value compounds, specifically ketones, using Pd/Ni@BNNS bimetallic catalysts. The influence of various parameters, such as salting-out agents, temperature, catalyst loading, and reaction time, significantly improved the ABE conversion to 98% with 86% higher ketone (C5–C11) selectivity. Furthermore, the heterogeneity and recyclability of the Pd/Ni @BNNSs catalyst were investigated, confirming its suitability for industrial-scale applications. By advancing biofuel synthesis technology and overcoming the drawbacks of conventional biofuels, this study contributes to the mitigation of the environmental and energy challenges facing the aviation industry.

Optimizing dimension selection for rain flow counting in fatigue assessment of large-scale lattice wind turbine support structures: A comprehensive study and design guidance

The selection of dimension (d) for the rain flow counting matrix significantly influences the reliable prediction of fatigue life in wind turbine support structures. However, there are limited public reports on the impact of dimensions on the fatigue assessment of wind turbine structures. This study explores the influence of dimensions on the fatigue assessment process and outcomes, focusing on a large-scale ultra-high lattice wind turbine support structure from an engineering project. Through integrated load simulation, fatigue load time series for different design load cases (DLCs) are obtained for the overall structure. The rain flow counting method is utilized to derive the overall rain flow counting matrix (Markov_n) with varying dimensions. Subsequently, employing a multi-scale fatigue assessment method, the damage matrix (Markov_D), cumulative fatigue damage (D), and fatigue life are computed. A detailed exploration examines the impact of rain flow counting matrix dimensions on Markov_n, Markov_D, D, fatigue life, and calculation time (t). Furthermore, guidance is provided for selecting the optimal dimension for engineering design. The findings indicate that selecting dimensions that are too small results in the loss and merging of smaller mean and amplitude load values, thereby failing to accurately represent the load history. Moreover, a small dimension yields an excessively cautious estimation of cumulative fatigue damage (D) and underestimates the fatigue life, consequently inflating construction expenses.

A Long-Term Power Supply Risk Evaluation Method for China Regional Power System Based on Probabilistic Production Simulation

To qualify the risk of extreme weather events for power supply security during the long-term power system transformation process, this paper proposes a risk probability evaluation method based on probabilistic production simulation. Firstly, the internal relationship of extreme weather intensity and duration is depicted using the copula function, and the influences of extreme weather on power security are described using the guaranteed power output ability coefficient, which can provide the extreme scenario basis for probabilistic production simulation. Then, a probabilistic production simulation method is proposed, which includes a typical-year scenario and extreme weather events. Meanwhile, an index system is proposed to qualify the power security level, which applies the loss of load expectation (LOLE) and time of loss of load expectation (TOLE) under different scenarios and other indices to reveal the long-term power security trend. Finally, the long-term power supply risks for the Yunnan provincial power system are analyzed using the proposed method, validating that the proposed method is capable of characterizing the influences of extreme weather on power security. The security level of different long-term power transformation schemes is evaluated.

Emotion-Driven Energy Load Forecasting: An Ensemble Leveraging Insights from News

In modern times, system energy load forecasting is an extremely important process in a variety of contexts. Moreover, energy load time series fluctuations are influenced by a wide range of factors, ranging, inter alia, from environmental conditions, natural events, and demographics to both regional and global geopolitical contexts, economic conditions, energy sources, policies, and regulations. Given these, this paper examines the integration of news information from the global scene into Greek energy load forecasting schemes through the use of sentiment analysis. Investigating the ways the general emotional footprint of news worldwide affects and can be used in an energy modeling context, we benchmark possible ensemble configurations incorporating a multitude of 31 emotion polarities. Building on our previous work, an ensemble method that exploits specific outputs from a multi-label sentiment classifier and a sentiment analysis procedure under a multivariate forecasting scheme is presented. It is shown, through an empirical evaluation of the results, that the integration of emotion representations related to non-Greek news concerning global current affairs improves the predictions.

Single Effective Complex Loading into Zero-Mode Waveguides Optimized with Fluorescence Evaluation at Quenching and Accumulation Checkpoints.

Single-molecule detection with high accuracy and specialty plays an important role in biomedical diagnosis and screening. Zero-mode waveguides (ZMWs) enable the possibility of single biological molecule detection in real time. Nevertheless, the absence of a reliable assessment for single effective complex loading has constrained further applications of ZMWs in complex interaction. Both the quantity and activity of the complex loaded into ZMWs have a critical effect on the efficiency of detection. Herein, a fluorescence evaluation at quenching and accumulation checkpoints was established to assess and optimize single effective complex loading into ZMWs. A primer-template-enzyme ternary complex was designed, and then an evaluation for quantity statistics at the quenching checkpoint and functional activity at the accumulation checkpoint was used to validate the effectiveness of complexes loaded into ZMWs. By optimizing the parameters such as loading time, procedures, and enzyme amount, the single-molecule effective occupancy was increased to 25.48%, achieving 68.86% of the theoretical maximum value (37%) according to Poisson statistics. It is of great significance to provide effective complex-loading validation for improving the sample-loading efficiency of single-molecule assays or sequencing in the future.

Optimization and modeling of solar photocatalytic degradation of raw textile wastewater dyes using green ZnO-ED NPs by RSM

ABSTRACT This study aims to use green ZnO-ED NPs produced from Eleocharis dulcis (E. dulcis) extract to maximize solar photocatalytic degradation of raw textile wastewater. The optimization of photocatalysis was decided using the response surface methodology (RSM) as a function of ZnO-ED NPs mass load (0.1–2 g), initial concentration (10–100%), pH (4–9), and contact time (60–200 min). The maximum decolorization (87.34%) and COD removal (100%) were recorded at pH 7, time (60 min), ZnO-ED NPs dosage (2 g/L), and 10% of color concentrations with R2 coefficient of 0.78 at p < 0.05. FESEM analysis showed the presence of granules with smaller diameters than the diameter of the ZnO-ED NPs granules before SPD. EDX analysis revealed the presence of impurities like copper (Cu). XRD analysis indicated the purity of ZnO-ED NPs after SPD, as the values were all quite similar to the XRD values before SPD. The results of an AFM analysis presented that agglomerations of ZnO-ED NPs, in contrast, were somewhat homogeneous in size, nature, and dispersion before SPD.

The Role of Vitamins, Magnesium, and Trace Elements in COVID-19 Treatment and Post-COVID-19 Rehabilitation: An Updated Overview.

This review summarizes the scientific knowledge concerning the impact of vitamins, magnesium, and trace elements on various mechanisms contributing to the possible treatment and prevention of COVID-19, including its delayed consequences. A search was conducted in various databases, including PubMed, Scopus, ClinicalTrials.- gov, and Web of Science. Among the main mechanisms involved in the effects of the studied micronutrients, immune-boosting, antioxidant and anti-inflammatory effects were also highlighted. The analyzed clinical trials confirmed that supplementation with higher daily doses of some micronutrients can reduce SARS-CoV-2 viral load and hospitalization time. The potential role of most known vitamins in preventing, treating COVID-19, and rehabilitating patients was considered. The most promising agents for combating COVID-19 and its consequences might be the following vitamins: vitamin D, ascorbic acid, polyunsaturated fatty acids (PUFAs), and some B complex vitamins. Inorganic elements deserving attention include magnesium and trace elements, such as zinc, selenium, copper, and iron. Some associations were found between micronutrient deficiencies and COVID-19 severity in children, adults, and older people. Patients can obtain the aforementioned micronutrients from natural food sources or as supplements/- drugs in various dosage forms. The reviewed micronutrients might be considered adjunctive treatment strategies for COVID-19 patients.