Limited Influence Research Articles

Investigation of fracture behavior and deformation capacity of high-strength steel butt-welded joints

Performance-based design of high-strength steel welded structures requires accurate prediction of their load-bearing capacity as well as deformation capacity. There have been several studies undertaken on the load-bearing capacity of high-strength steel butt-welded (HSSBW) joints, but very few studies are performed on their deformation capacity. This study investigates the fracture behavior as well as the deformation capacity of double-V HSSBW joints with strength-matching welding materials, taking into account the effects of different heat inputs, steel strengths, and steel processing methods. To evaluate the deformation capacity, fracture initiation criterion, and fracture propagation model of four zones within the butt-welded joints, including hardened heat-affected zone (HHAZ), softened heat-affected zone (SHAZ), welding material zone (WM), and base metal zone (BM), are first calibrated from experimental results and numerical analysis results. The calibrated material models are validated against the test data. Numerical analyses are then performed to predict the fracture behavior and deformation capacities of the welded joints utilizing the verified material models. According to the analysis results, heat inputs no more than 1.9 kJ/mm impose a limited influence on the fracture behavior of each zone within the double-V HSSBW joints. If the heat input is below 1.9 kJ/mm, QT steel welded joints exhibit a higher deformation capacity than TMCP steel welded joints. When compared to the tension specimens made of pure base metal, the reduction of the deformation capacity of the double-V HSSBW joints was even more than 30 % and it is more significant than the reduction of load-bearing capacity, therefore, evaluation of the deformation capacity of the welded joints is very essential for the performance-based design of high-strength steel welded structures.

Community solar PV adoption in residential apartment buildings: A case study on influencing factors and incentive measures in Wuhan

The potential benefits of adopting PV (photovoltaic) in residential apartments in China, such as reducing peak demand and electricity transmission issues, have been overlooked. Community PV is more applicable for most Chinese cities residents living in apartment buildings. However, existing studies failed to provide comprehensive insight regarding factors influencing community PV adoption and adoption decision strategies. This study utilized a discrete choice experiment performed in Wuhan to examine individuals' community PV adoption preferences and analyze the factors influencing their decisions. The study found that respondents who were well-educated, older than 40, lived in residential buildings constructed earlier than 2006, had a living area >120 m2, or used AC for more months in the summer were more likely to adopt PV. Three decision strategies (classes) with different PV product preferences were identified. Peer effect is identified to significantly influence the community PV adoption as almost 65% of the respondents are more likely to adopt PV if there are high neighboring PV adoption or installation agreement rates. Cost was not a determining factor for a significant proportion of respondents, who instead focused on revenue. Subsidy policies also had limited influence, affecting only about 43% of respondents. Policy implications are provided based on the research results.

PSXII-5 Genetic Parameters for Dry Matter Intake in Beef Cattle as a Function of Water Restriction: Insights into Environmental Sensitivity and Genetic-By-Environment Interactions

Abstract Genetic selection for animals more tolerant or less sensitive to inadequate water availability may become critical to beef production, particularly as water resources become scarce or represent a meaningful cost to producers. The objectives of this study were 1) to explore the genetic component and environmental sensitivity (ES) of dry matter intake (DMI) to water restriction (WR), and 2) to evaluate genetic-by-environment interactions (G×E) with respect to WR using a reaction norm. A group of 788 crossbred steers arranged across seven cohorts were provided feed and water whereby daily water intake (WI) and DMI values were recorded automatically on an individual basis. After an initial acclimation period, data were collected for 70 days in which ad libitum water was provided and baseline WI was determined on each steer. Next, steers were restricted by approximately 10% of their baseline WI every seven days until 50% WR was achieved and subsequently maintained for 42 days. The reaction norm was modeled with a linear random regression allowing for additive genetic animal-specific intercepts and slope parameters as a function of the WR environmental covariate. The relationship covariance matrix for the additive genetic animal parameters was estimated using genotypes. The model was fit using the THR3GIBBSf90 program in the BLUPf90 software. The additive genetic variances for animal-specific intercepts and WR-driven slopes, as well as their covariance, were estimated. The estimated (posterior median and 95% highest posterior density) ES to WR, represented by the regression coefficient on the WR covariate, was -0.410 (-0.422, -0.399) kg daily DMI per 10% WR, indicating evidence for population-level DMI sensitivity to WR. The estimated additive genetic correlation between animal-specific intercept (i.e., ad libitum WI) and animal-specific slope (i.e., sensitivity to WR) was -0.75 (-0.88, -0.59), supporting an association between selection for increased DMI at ad libitum WI and ES. The additive genetic correlation between DMI at 0% and 25% WR was estimated at 0.96 (0.94, 0.99) and at 0% and 50% WR was 0.78 (0.65, 0.91), thereby indicating G×E had limited influence on the overall EBV ranking of animals as WR increased. The results of this study do not indicate major G×E concerns in DMI with respect to WR in the overall population; however, ES to WR may be important to producers as selection on DMI at ad libitum WI could increase ES.

Social Themed Post LinkedIn Can Affect Engagement Rate as Social Media Professional Platform For Business to Business (B2B)

This research investigates the influence of social theme-oriented content on the LinkedIn platform on business-to-business (B2B) enterprise in Indonesia. The unit of analysis in this study is a B2B corporation located in Indonesia. The research methodology employed is a quantitative approach, specifically utilizing secondary data analysis. The findings of the study indicate that posts centered around social themes had a statistically significant and favorable effect on the number of followers a company gained on LinkedIn. However, it is noteworthy that these posts did not exhibit a statistically significant impact on levels of engagement and impressions. The limited influence of social theme-based postings on user engagement and impressions could potentially be attributed to users' inclination towards more professional material and the presence of competing content in the same thematic category. Additional factors, such as the timing of posts, the underlying objectives, and the maintenance of brand coherence, also exert a significant influence. Hence, it can be argued that LinkedIn postings centered around social themes primarily contribute to the growth number of followers, rather than enhancing engagement and impressions. This study offers valuable insights into the utilization of the LinkedIn platform by B2B enterprises for the purpose of cultivating a number of followings. It highlights the significance of developing a content strategy that aligns with the preferences of the target audience and the unique qualities of the platform.
 
 Received: 24 June 2023 / Accepted: 5 October 2023 / Published: 5 November 2023

Understanding the relationship between poverty, environmental degradation, and power dynamics: a qualitative study in Northern Ghana

AbstractThis study investigates the connection between poverty, power dynamics and environmental degradation, focusing on the specific context of Northern Ghana. Within the remits of environmental degradation, agriculture has long been acknowledged as a significant contributor to the depletion of environmental resources, although, recent discussions have highlighted the differential impact of poor and rich farmers. Employing a qualitative approach and utilizing multistage sampling techniques, this research delves into how poverty or wealth influences deforestation and water pollution, as well as the persistent narratives surrounding the primary drivers of environmental degradation. Qualitative data were gathered from 35 participants through semi-structured interviews. The interviews lasted between 45 min and 1 h. The data were analyzed thematically to explore the relationships between poverty, environmental degradation, and power dynamics in agricultural practices. The findings reveal that both poor and rich farmers contribute to deforestation, with rich farmers playing a substantial role in the expansion of farming activities. Additionally, the study uncovers that water pollution is predominantly caused by wealthier farmers, through the spillover of agrochemicals. Significantly, the study highlights the exclusion of the poor from poverty-environment studies and their limited power and influence as crucial factors that perpetuate the prevailing poverty-resource-depletion narrative. This study emphasizes the need to contextualize the poverty-environmental degradation nexus, recognizing it as a result of power dynamics and political agendas. The implications of these findings extend to policy formulation, underscoring the necessity of addressing underlying discourses of power for sustainable environmental management.

Effects of the fillers on the interface strength of the hat-stiffened composite panel

Hat-stiffened composite skins have been widely used in primary structures of aircraft components. The bonding strength at the stiffener-skin interface is critical to ensure the advanced load-bearing capacity of the stiffened skin, whereas, the deltoid regions are usually the weakest locations because of the geometrical singularity. Inserting fillers into the deltoid regions could alter the bonding strength. In this study, a series of four-point bending tests are conducted on the co-cured hat-stiffened composite skin specimens with and without fillers and with different pre-fabricated debonding defects, furthermore, finite element simulations are implemented to predict the failure process. The stiffness, initial failure load, failure mode and failure process are analyzed to obtain the influences of the fillers on the damage tolerance of the hat-stiffened composite panels, and the influential mechanisms were revealed by the combined analyses of the test and simulation results. It is found that the usage of fillers can increase the initial stiffness of the panel without prefabricated defects by about 10%, but provide limited influence on the initial failure load. The pre-fabricated debonding defect along longitudinal direction has little influence on the stiffness and failure load, but the influence of the defect along transverse direction are higher. The initial failure of all hat-stiffened composite panels with/without filler and with/without prefabricated defects under four-point bending onsets around the deltoid region. The usage of the fillers changed the load transfer and the stress status in the deltoid region of the hat-stiffened composite panels and as a consequence, the initial failure modes were changed and the failure load were increased by the fillers. This work provides a technical support for the damage tolerance design and strengthening method of hat-stiffened composite structures.

Co-immersion in Audio Augmented Virtuality: the Case Study of a Static and Approximated Late Reverberation Algorithm.

In immersive Audio Augmented Reality, a virtual sound source should be indistinguishable from the existing real ones. This property can be evaluated with the co-immersion criterion, which encompasses scenes constituted by arbitrary configurations of real and virtual objects. Thus, we introduce the term Audio Augmented Virtuality (AAV) to describe a fully virtual environment consisting of auditory content captured from the real world, augmented by synthetic sound generation. We propose an experimental design in AAV investigating how simplified late reverberation (LR) affects the co-immersion of a sound source. Participants listened to simultaneous virtual speakers dynamically rendered through spatial Room Impulse Responses, and were asked to detect the presence of an impostor, i.e., a speaker rendered with one of two simplified LR conditions. Detection rates were found to be close to chance level, especially for one condition, suggesting a limited influence on co-immersion of the simplified LR in the evaluated AAV scenes. This methodology can be straightforwardly extended and applied to different acoustics scenes, complexities, i.e., the number of simultaneous speakers, and rendering parameters in order to further investigate the requirements for immersive audio technologies in AAR and AAV applications.

Investigation on cost-effective composites for CO2 adsorption from post-gasification residue and metal organic framework

Cost-effective CO2 adsorbents are gaining increasing attention as viable solutions for mitigating climate change. In this study, composites were synthesized by electrochemically combining the post-gasification residue of Macadamia nut shell with copper benzene-1,3,5-tricarboxylate (CuBTC). Among the different composites synthesized, the ratio of 1:1 between biochar and CuBTC (B 1:1) demonstrated the highest CO2 adsorption capacity. Under controlled laboratory conditions (0°C, 1 bar, without the influence of ambient moisture or CO2 diffusion limitations), B 1:1 achieved a CO2 adsorption capacity of 9.8 mmol/g, while under industrial-like conditions (25°C, 1 bar, taking into account the impact of ambient moisture and CO2 diffusion limitations within a bed of adsorbent), it reached 6.2 mmol/g. These values surpassed those reported for various advanced CO2 adsorbents investigated in previous studies. The superior performance of the B 1:1 composite can be attributed to the optimization of the number of active sites, porosity, and the preservation of the full physical and chemical surface properties of both parent materials. Furthermore, the composite exhibited a notable CO2/N2 selectivity and improved stability under moisture conditions. These favorable characteristics make B 1:1 a promising candidate for industrial applications.

CFD- and BPNN- based investigation and prediction of air pollutant dispersion in urban environment

This study employed a Computational Fluid Dynamics (CFD)-based back propagation neural network (BPNN) to investigate and predict the pollutant dispersion in an ideal urban environment. The training and test datasets were generated using the Reynolds-averaged Navier–Stokes (RANS) model, which involved 60 cases by varying reference inflow speeds, NO & NO2, and ambient O3 concentrations. The results indicated that the ambient flow was gradually decoupled from the reversed flow at each building's leeward zone further downstream, leading to heightened difficulty in pollutant elimination. Upstream buildings located in front of the emission source were rarely affected by pollutants, regardless of changes in Damköhler numbers (Da). While varying DaNO provides a limited influence, confining DaO3 can effectively reduce hazardous pollutants' impact around the emission source vicinity, on the urban streets, and in the further downstream area of the building array. A budget analysis showed that increasing DaO3 primarily enlarged the chemical reactions’ effects on NO increase within the urban residential area. Finally, the BPNN model demonstrated a high accuracy in predicting wind speed and NO concentration within a few seconds. These findings provide valuable insights for designing effective strategies to mitigate hazardous pollutants’ impacts in urban environments.

Heating affects protein digestion of skimmed goat milk proteins with different casein:whey ratios under simulated infant conditions

This research compared effects of heating on the digestion of goat milk proteins in skimmed goat milk model systems with different casein-to-whey protein ratios. The digestion was evaluated both the supernatant and gastric clot part of the digesta. Whey protein concentrates were added in skimmed goat milk (80% casein, C80 sample) to make a 40% casein sample (C40 sample). Heating at 65 °C showed limited influence on digestibility of proteins in supernatant and clot of both model systems. In the supernatant, the C80 sample had a higher soluble protein concentration after 85 °C heating, compared to the C40 sample. After heating at 85 °C for 30 min, the digestibility of proteins in the supernatant of C40 and C80 samples was increased. This heating also increased the casein digestibility of the gastric clot of C80 sample, but resulted in more undigested whey protein aggregates in C40 sample. For the difference between C80 and C40 sample, the proteins in the supernatant of C80 samples showed a higher digestibility than those in the supernatant of C40 samples, both in non-heated and in 85 °C heated samples. The clots of C40 sample showed a relatively higher digestion rate than C80 sample clots, which may be due to their higher water content and looser microstructure. Overall, this study showed that heating induced different digestion kinetics of goat milk model systems with different casein-to-whey ratios.

Study of the Seismic Behavior of Simplified RCS Joints via Nonlinear Finite Element Analysis

Compared to more complex structures, simply configured reinforced concrete column–steel beam (RCS) composite structures have more promising application prospects, especially in regions with moderate–high seismic levels, due to their ease of construction. However, the current understanding of the seismic performance of simplified RCS joints is not sufficient. Validated by experimental results, a nonlinear finite element analysis (FEA) model was developed in this study to reveal the seismic behavior of simplified RCS joints. Six vital design parameters, namely axial load ratio, concrete strength, yield strengths of steel webs and flanges, and diameters of transverse and longitudinal reinforcements, were comprehensively studied. Research has shown that the axial compression ratio has a significant impact on the failure mode and bearing capacity of joints. When the concrete strength increases, the load-bearing capacity of the joints significantly increases, while the brittleness of high-strength concrete leads to a decrease in its deformation capacity. In addition, when the steel beam strength is constant, higher flange and web yield strengths have a limited influence on crack propagation and strain development. The stirrup reinforcement ratio and longitudinal reinforcement ratio play a significant role in inhibiting crack propagation and improving the bearing capacity, respectively. With the help of the numerical results, six theoretical models introduced by national codes and other researchers were compared. Among them, the modified model proposed by Kanno demonstrated the highest accuracy and was the most suitable for simply configured RCS joints.

Serum PCDD/F levels in metropolitan populations living near a municipal solid waste incinerator in Eastern China

Ambient exposure to polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) is suspected to cause adverse human health outcomes. Herein, serum samples from 40 residents in the neighborhood of a municipal solid waste incinerator (MSWI) in the metropolitan area were measured for PCDD/Fs. The mean toxic equivalent (TEQ) concentration of total PCDD/Fs in human serum samples was 16.8 pg TEQ/g lipid. Serum PCDD/F levels were significantly higher in residents adjacent to the MSWI than in those from areas far from the emission source (p < 0.01). In addition, there were no significant associations between serum PCDD/Fs levels and factors, such as gender, age, and BMI in donors. For non-occupationally exposed populations, OCDD and 1,2,3,7,8-PeCDD in serum are available as indicators of total PCDD/Fs and total TEQ, respectively. The atmospheric PCDD/Fs levels were within a relatively low range in areas upwind and downwind of the MSWI. The results of the principal component analysis showed a distinct difference in PCDD/F congener patterns between air and serum samples, suggesting inhalation exposure could have a limited influence on the human body burden. Our findings will deepen the current knowledge of endogenous PCDD/F exposure in urban populations, and also facilitate public health protection strategies near MSWIs.

Effect of data quality on results of Reverse Monte Carlo analysis of EXAFS data

Reverse Monte Carlo (RMC) is a computational technique used to generate three-dimensional atomic structural models compatible with a given set of experimental data. RMC is applicable to X-ray absorption fine structure (XAFS) data, which generally show different energy ranges and noise levels depending on the experimental conditions. In this article, we explore the relationship between these effects and the precision of structural results obtained through RMC, by examining two simple molecular cases. In such specific cases (Br2 and BBr3) we have found that the XAFS data range has generally a limited influence on the structural results, except for signals on restricted wave-vector ranges (kmax<8A−1). Different noise levels are shown to affect the precision of the structural results, depending also on how the noise is included in the RMC procedure. As an outcome of this study, we propose general guidelines for best practices in RMC XAFS data-analysis, aiming to improve the accuracy and reliability of atomic structure modeling.

Sound wave propagation in rarefied molecular gases

Sound wave propagation in rarefied flows of molecular gases confined in micro-channels is investigated numerically. We first validate the employed kinetic model against the experimental results and then systematically study the gas damping and surface force on the transducer as well as the resonance/anti-resonance in confined space. To quantify the impact of the finite relaxation rates of the translational and internal energies on wave propagation, we examine the roles of bulk viscosity and thermal conductivity in depth over a wide range of rarefactions and oscillation frequencies. It is found that the bulk viscosity only exerts influence on the pressure amplitude and its resonance frequency in the slip regime in high oscillations. In addition, the internal degree of freedom is frozen when the bulk viscosity of a molecular gas is large, resulting in the pressure amplitude of sound waves in the molecular gas being the same as in a monatomic gas. Meanwhile, the thermal conductivity has a limited influence on the pressure amplitude in all the simulated flows. In the case of the thermoacoustic wave, we prove that the Onsager–Casimir reciprocal relation also holds for molecular gases, i.e. the pressure deviation induced by the temperature variation is equal to the heat flux induced by the plate oscillation. Our findings enable an enhanced understanding of sound wave propagation in molecular gases, which may facilitate the design of nano-/micro-scale devices.

MP-PIC study of particle flow characteristics of pneumatic conveying process in a vertical pipe

The transportation of granular materials is commonly achieved through pneumatic conveying. In this study, the multiphase particle-in-cell model was adopted to investigate the dense phase pneumatic conveying in a vertical pipe. The simulation results were consistent with experimental data, with an error of less than 4%. The study examined the effects of varying particle size distribution (PSD), pipe diameters, and superficial gas velocities on the flow field and particle characteristics in this process. The findings revealed that the largest dispersion coefficient of particles was along the conveying direction. PSD has slight effect on dispersion coefficients. However, when the superficial gas velocity is increased from 1 m/s to 2.5 m/s, particle dispersion coefficients increases by approximately 115.22%. Formation and evolution of the plug can be observed during the pneumatic conveying process. PSD has a limited influence on particle slip velocity, but affects the particle Reynolds number.

A matheuristic approach for the multi-level capacitated lot-sizing problem with substitution and backorder

The lot-sizing problem aims at determining the products to be produced and their quantities for each time period, which is a difficult problem in production planning. This problem becomes even more complicated when practical aspects such as limited production capacity, bill of materials, and item substitution are considered. In this paper, we study a new variant of the lot-sizing problem, called the multi-level capacitated lot-sizing problem with substitution and backorder. Unlike previous studies, this variant considers substitutions at both the product and component levels, which is based on the real needs of manufacturers to increase planning flexibility. Backorders are allowed, but should be delivered within a certain time limitation. We formulate this problem using a mathematical programming model. A matheuristic approach is proposed to solve the problem. This first generates an initial feasible solution using a relax-and-fix algorithm, and then improves it using a hybrid fix-and-optimise algorithm. The proposed algorithm is calibrated with a full factorial design of experiments, and its efficiency is well validated. Finally, through extensive numerical experiments, we analyse the properties of this new lot-sizing problem, such as the effect of substitution options, and the influence of backorder time limitation, and provide several useful managerial insights for manufacturing companies to save costs in production planning.

Adjusting the pomace ratio during red wine fermentation: Effects of adding white grape pomace and juice runoff on wine flavoromics and sensory qualities

Adding pomace or juice runoff during maceration is a traditional winemaking process. To mitigate the negative effects of rainfall during harvest and examine the effects of adjusting the pomace ratio during fermentation on the flavor profile of Marselan grape wines, the prefermentation addition of Petit Manseng grape pomace (PAP) and prefermentation juice runoff (PJR) was determined. The phenolic and volatile compounds were investigated using HPLC–MS and GC–MS. PAP enriched the flavanols and PJR enriched the pigment and copigment matrix. Approximate 10% increase in the ratio of pomace promoted the formation of anthocyanin derivatives. The increased pomace ratio reduced the concentration of volatile compounds without impacting the aroma quality. Sensory analysis revealed PAP wines scored higher for acidity and astringency and PJR wines scored higher for color. In conclusion, an appropriate increase in the pomace ratio of approximately 10% can enhance the color and mouthfeel of the wine while having a limited influence on aroma.

Inspecting the role of vapour loss and other model strategies in the mod-elling of a bentonite thermo-hydraulic cell

Inspecting the role of vapour loss and other model strategies in the mod-elling of a bentonite thermo-hydraulic cell

The Influence of Work Motivation and Organizational Communication on Performance of Health Social Security Provider (BPJS) Employees

The aim of this study is to determine the relationship between organizational communication and employee motivation as well as the relationship between organizational communication and employee performance. The study's conclusions indicate that corporate communication has a limited influence on the employee performance variable. The t-test findings, which had a significance level of 0.000 &lt; 0.05 and a t-count value that was higher than the t-table, serve as evidence for this. The results of the t-test with a significance value of 0.000 &lt; 0.05 and a t-count value that is larger than the t-table suggest that work motivation partially proves that it has an effect on employee performance. Both corporate communication and work motivation have a substantial impact on employee performance. This is shown by the results of the f-test, which show an f-count value greater than f-table and a significance value of 0.000 &lt; 0.05.

Viscous effects on morphological and thermodynamic non-equilibrium characterizations of shock–bubble interaction

A two-fluid discrete Boltzmann model with a flexible Prandtl number is formulated to study the shock–bubble interaction (SBI). This paper mainly focuses on the viscous effects on morphological and thermodynamic non-equilibrium (TNE) characterizations during the SBI process. Due to the rapid and brief nature of the SBI process, viscosity has a relatively limited influence on macroscopic parameters but significantly affects the TNE features of the fluid system. Morphologically, viscosity affects the configuration of the vortex pair, increases both the amplitudes of gradients of average density and average temperature of the fluid field, and reduces circulation of the bubble. As a higher viscosity fluid absorbs more energy from the shock wave, it leads to an increase in both the proportion of the high-density region and the corresponding boundary length for a fixed density threshold. The spatiotemporal features of TNE quantities are analyzed from multiple perspectives. The spatial configuration of these TNE quantities exhibits interesting symmetry, which aids in understanding the way and extent to which fluid unit deviates from the equilibrium state. Theoretically, viscosity influences these TNE quantities by affecting the transport coefficients and gradients of macroscopic quantity. Meanwhile, the viscosity increases the entropy production rate originating from the non-organized momentum flux mainly through amplifying the transport coefficient and enhances the entropy production rate contributed by the non-organized energy flux by raising the temperature gradient. These multi-perspective results collectively provide a relatively comprehensive depiction of the SBI.