Effect Of Spread Research Articles

Numerical investigation of the Pedrógão Grande pyrocumulonimbus using a fire to atmosphere coupled model

Understanding the development of fire-generated thunderstorms in mega fire events is important given their high impact on the evolution of the fire fronts, where the fire spread becomes highly unpredictable and difficult to suppress. This study aims to investigate numerically the influence of strong pyro-convective activity on the local atmospheric conditions by means of a numerical simulation based on the coupled Meso-NH/ForeFire code. To our knowledge, it is the first time that the effect of wildfire spread on the local atmospheric conditions is accounted explicitly in a high-resolution NWP model to investigate pyro-convection activity. More specifically, we study numerically the Portuguese Pedrógão Grande mega fire, which was one of the most destructive and deadliest wildfire hazards affecting the Mediterranean region in the recent years. The spatio-temporal propagation of the wildfire was assigned a priori on the basis of the official investigation's reports, while the impact of the forced fire evolution and of the ensuing heat and water vapour emissions on the local atmospheric conditions is accounted explicitly. The simulation, configured with very-high spatial and temporal resolutions, was capable of resolving the intense convective column reaching the upper troposphere and the fast development of the associated cloud system. The numerical fire produced intense updraughts with vertical velocities above 15 m/s, whereas the associated pyroCb cloud was composed by five different hydrometeor species along the main convective column and reached an altitude of 10 km. It is remarkable that the numerical experiment reproduced phenomena occurring at a fine scale related to cloud microphysics, such as very-localized outflows. This study, based on a coupled numerical simulation, was capable of illustrating in detail the development of a pyroCb cloud from strong pyro-convective activity.

Design of slurries for 3D printing of sodium-ion battery electrodes

Additive manufacturing of battery electrodes, using syringe deposition 3D printing or direct ink writing methods, enables intricate microstructural design. This process differs from traditional blade or slot-die coating methods, necessitating tailored physical properties of composite slurries to ensure successful deposition. Inadequately optimised slurries result in non-uniform extrusion, and challenges such as nozzle swelling or slumping, result in compromised structural integrity of the print, limiting the resolution. This study focuses on developing slurry design principles by thoroughly characterising the rheology of several water-based hard carbon anode slurry, both in shear and extension. Hard carbon is chosen as a material of significant importance for future sodium-ion batteries, and an example for this optimisation. The slurry composition is tailored to introduce yield stress by incorporating network-forming binder (carrageenan) and additive (carbon nanotubes), effectively reducing spreading, and preserving the printed coating's structure. Validation is performed through printing a large width line and evaluating spread. The same slurry is deposited on a smaller 150 μm nozzle, which introduces die swell and spreading effects. This offers insights for further optimization strategies. The strategies developed in this research for characterizing and optimizing the rheology through formulation lay the groundwork for the advancement of detailed 3D printed electrodes, contributing to the progress of additive manufacturing technologies in the field of battery manufacturing.

Forest model dynamics analysis and optimal control based on disease and fire interactions

<abstract><p>Three models for the propagation of forest disease are revisited to include the effect of forest fires and disease spread. We study the global stability of the forest-disease model in the absence of forest fires and the spread of disease. When forest fires caused by grass cover are considered, we show that the equilibrium points are locally asymptotically stable. If both forest fires and the spread of disease exist in the second model, then Turing instability can occur. In this case, the system exhibits complex dynamic behavior. To determine the effect of fire on the forest disease model, we obtain the optimal control expression of the key parameter fire factor, and carry out sensitivity analysis. Finally, we use forest biomass data of some provinces in China from 2002 to 2018 for numerical simulation, and the results are in agreement with the theoretical analysis.</p></abstract>

Trend of Vegetable Oils International Trade of India

The Covid-19 pandemic has had a major impact on the world economy, more than in the last century. The trade in agricultural products plays an important role in the food security of the people of the world. In this situation, the Government of India has called for a general lockdown to protect the people from the effects of the disease spread. This paper analyses in detail the impact of the pandemic on the India’s international trade in vegetable oilsand its trend over the last 10 years from2010-11 to 2020-21. Accordingly, despite the sharp decline in exports and imports of industrial goods in the international trade of India, export and import of vegetable oils were increased well. But, its impact has different effects on different commodities.

Effect of pylon tower spread on modal time period of cable-stayed suspension hybrid bridge

Effect of pylon tower spread on modal time period of cable-stayed suspension hybrid bridge

Effect of Pylon Tower Spread on Modal Time Period of Cable-Stayed Suspension Hybrid Bridge

Effect of Pylon Tower Spread on Modal Time Period of Cable-Stayed Suspension Hybrid Bridge

Effect of Anti-Reflective and Dust Spreading on Performance of Solar PV Panels

This study intends to better solar photovoltaic (PV) panel performance by employing anti-reflective coating and explore how dust affects solar panel effectiveness. Three equivalent solar PV panels were compared, having one of them being uncoated, the next one having a TiO2 nanomaterial coating, and the very last one having a SiO2 nanomaterial coating. PV panel surfaces are coated with superhydrophilicity TiO2 as well as superhydrophobic SiO2 nanomaterials using a cloth made of microfibers. With the aid of a photovoltaic (PV) analyser, the power output of each and every PV panel has been monitored during the month of November 2021. After one month of being exposed to the environment, the percentage improvement in efficiency for TiO2-coated panels was 7.66% and for SiO2 coated panels was 19.73% as compared to uncoated PV panels. Results demonstrate that SiO2 covered PV panels outperform the other two scenarios in terms of efficiency and power output. The frequency of photovoltaic panel washing is reduced by the application of coating. Different amounts of dust are evenly scattered on the surface of the PV panel in order to observe the effect of the dust. Additionally, as the amount of dust increases, the effectiveness of PV panels declines considerably. When 20g of dust is dispersed across the surface of a PV panel, its efficiency falls by 34.6 percent.

Powder spreading effects on laser powder bed fused parts quality

Laser powder bed fusion (LPBF) is an additive manufacturing technique whose efficiency and quality depend largely on a consistent and precise powder spreading procedure. This article examines the crucial role of powder spreading in influencing the quality of 3D-printed parts. Through case studies and experimental results, the article demonstrates in detail the impact of parameters such as: powder flowability, spreading speed, layer thickness, and recoater type on powder uniformity during spreading. In addition, the paper presents a comparison between types of recoaters in order to obtain optimum surface finish, mechanical properties, and reduced defects. This paper reviews the most appropriate powder spreading techniques to maintain the flowability and uniformity of the powder. Therefore, the primary objective of this work is to present an in-depth review of the impact of powder spreading dynamics in LPBF. In addition, it aims to demonstrate to the reader the various factors influencing powder spreading and the methodologies employed to optimize this crucial process.

OPM-MEG Measuring Phase Synchronization on Source Time Series: Application in Rhythmic Median Nerve Stimulation.

The magnetoencephalogram (MEG) based on array optically pumped magnetometers (OPMs) has the potential of replacing conventional cryogenic superconducting quantum interference device. Phase synchronization is a common method for measuring brain oscillations and functional connectivity. Verifying the feasibility and fidelity of OPM-MEG in measuring phase synchronization will help its widespread application in the study of aforementioned neural mechanisms. The analysis method on source-level time series can weaken the influence of instantaneous field spread effect. In this paper, the OPM-MEG was used for measuring the evoked responses of 20Hz rhythmic and arrhythmic median nerve stimulation, and the inter-trial phase synchronization (ITPS) and inter-reginal phase synchronization (IRPS) of primary somatosensory cortex (SI) and secondary somatosensory cortex (SII) were analysed. The results find that under rhythmic condition, the evoked responses of SI and SII show continuous oscillations and the effect of resetting phase. The values of ITPS and IRPS significantly increase at the stimulation frequency of 20Hz and its harmonic of 40Hz, whereas the arrhythmic stimulation does not exhibit this phenomenon. Moreover, in the initial stage of stimulation, the ITPS and IRPS values are significantly higher at Mu rhythm in the rhythmic condition compared to arrhythmic. In conclusion, the results demonstrate the ability of OPM-MEG in measuring phase pattern and functional connectivity on source-level, and may also prove beneficial for the study on the mechanism of rhythmic stimulation therapy for rehabilitation.

Enhancing fire safety in underground mines: Experimental and large eddy simulation of temperature attenuation, gas evolution, and bifurcation influence for improved emergency response

The occurrence of underground mine fires remains a significant and persistent safety challenge in the mining industry, posing imminent risks to both miners' lives and the operational integrity of mining facilities. Current underground mine fire studies lack scale accuracy due to lab experiments and fail to consider bifurcation effects on smoke gas temperature. This study performed full-scale experiments and built validated CFD models to explore the interactive impact of ventilation and fire size on temperature attenuation, gas behavior, and CO generation in underground mines. A new empirical correlation for temperature decay in the mine drift was developed and its accuracy was compared with established models in the literature. In addition, the influence of bifurcation on maximum smoke temperature was analyzed. This research combines full-scale experiments and validated CFD modeling to address major gaps in underground mine fire studies. Unlike previous methods, this study explores the interactive effects of ventilation, fire size, temperature attenuation, and toxic gas spread, offering unprecedented insights. This innovation enables the development of tailored fire safety standards for mines, ensuring safer designs, rapid fire suppression, and improved evacuation strategies. By bridging theory and practice, this work transforms fundamental knowledge, empowering the mining industry to enhance safety measures, protect lives, and mitigate the impact of underground mine fires.

Governing Online Rumor: An Uncertain Intervention Timing Model for Online Rumor Propagation from the Perspective of Government

In view of different types of online rumors, when the governance institutions (government departments) intervene to achieve the least cost and the best effect is a core issue of rumor governance. Based on the perspective of the government, under the premise of limited human, material and financial resources, and considering the different impacts of government intervention opportunities on the spread of different types of rumors, this paper establishes an uncertain multi-objective network rumor transmission intervention timing model, so as to achieve the optimal allocation of government intervention opportunities for different types of online rumors, minimize the total cost and maximize the inhibition effect of rumor spreading. Then, the equivalent form of the model is given, and the model is solved. In addition, numerical experiments are conducted on three types of rumors during the COVID-19 pandemic. The experimental results show that when the types of online rumors and the focus of government departments on cost and governance effect are different, the optimal time for intervention will change. Finally, combined with the experimental results, corresponding countermeasures and suggestions are put forward for the supervision of online rumors by government departments.

Seasonality of Water Exchange in the Northern South China Sea from Hydrodynamic Perspective

In this study, we utilized exposure time (θ¯) as a key metric to investigate water exchange and its spatiotemporal variations in the Northern South China Sea (NSCS). The Eulerian adjoint method and Lagrangian tracking were adopted to capture a comprehensive view of water exchange in coastal regions. Our findings reveal distinct spatial and seasonal variations in θ¯. Spatially, a long θ¯ (exceeding 150 days) appears in the coastal region, and the largest values occur in the Beibu Gulf (300 days). Temporally, θ¯ exhibits clear seasonal patterns across the extensive shelf area, influenced by the seasonal monsoon which induced seasonally reversing shelf current and results in symmetrical distribution patterns of θ¯ across the board shelf during both winter and summer months. θ¯ is longer in winter than in summer. The study also revealed pronounced vertical contrasts in cross-isobath transport over the NSCS shelf, though significant vertical variations in net exchange time were noted only in specific locations, including the northeast side of Hainan Island, the Beibu Gulf mouth, and along the west side of Taiwan Island. The Beibu Gulf emerged as a critical factor in the NSCS’s water exchange dynamics in both seasons. In summer, it impacts more than 20% of the water exchange over adjacent areas, particularly through its westward transport against typical northeastward shelf currents. This highlights the combined effect of the westward spread of the Pearl River freshwater and the stable slope current on regional hydrodynamics. In winter, the Gulf’s retention characteristics profoundly affected even distant areas, contributing to up to 50% of water exchange, showing its broad impact on the NSCS’s water dynamics throughout the year.

Robust quantitative estimation of the seismic attenuation from shallow geotechnical borehole VSP data

Estimating seismic attenuation from shallow geotechnical borehole surveys can be a delicate task. Measured data are often collected within the source near-field domain and the classic inverse-distance correction of the geometric spreading (GS) is inappropriate at this scale. We develop a novel approach based on a 3D full-waveform modeling to substitute the inverse-distance correction. It consists of scaling the picked amplitudes using their counterparts obtained from an elastic simulation carried out under conditions mimicking the data acquisition. The seismic attenuation may be inferred from the corrected amplitudes using either a piecewise regression or a ray-based inversion. Numerical experiments involving P- and S-wave synthetic data indicate that our correction better compensates for the GS effect than the inverse-distance correction. For a synthetic example with 5% noise, the Q-factor values derived from amplitude corrected via the proposed approach have a relative error of approximately 10% compared with 40% for the traditional correction. We investigate the effect of the velocity and density uncertainty upon the calculated correction terms and show that our approach is unbiased and stable. Finally, the robustness of our workflow is assessed on a real case study involving a P-wave data set acquired in a geotechnical borehole.

Strategies for the measurement and prediction of balcony insertion loss

The change in noise level inside a building due to the presence of balconies is an important consideration for predicting traffic noise intrusion, with the ISO 12354-3:2017 standard providing recommended correction factors to model the effect. Data from scale model experiments is more comprehensive than in situ data, however these experiments define the balcony insertion loss as measured on the external facade behind the balcony rather than inside the building. This paper presents new methods to both measure and predict the insertion loss for each of the two definitions. In situ octave band measurements of traffic noise are undertaken i) at the balcony opening, ii) on the facade behind the balcony, iii) inside the building with the glazing closed, iv) inside the building with the glazing open, and are compared to v) a time-synchronized reference microphone placed in front of the balustrade, correcting the noise reduction for spreading and coherence effects. The insertion loss on the external facade was found to generally increase with frequency, which results in the overall A-weighted insertion loss inside the building being lower than that measured on the external facade. This difference is shown to be dependent on the amount of absorption within the balcony and the location of the noise source.

Bond default risk transmission through a common underwriter: evidence from China

Using samples of corporate bonds issued by Chinese A-share firms from 2014 to 2021, we examine whether information about bond defaults transmits to other bonds underwritten by a common underwriter. We document that during the underwriting process for a new corporate bond, if any prior bonds underwritten by the same underwriter have defaulted, the yield spread of the new corporate bond increases significantly. Specifically, such a new bond, on average, has a yield spread that is 16.8 basis points higher than one without a common underwriter. The results suggest that investors perceive the default risk of a new bond increases due to a deteriorated reputation of the underwriter. Additional analyses suggest that the adverse effect of the new bond yield spread is less salient when an underwriter has a strong reputation, is state-owned, or has foreign shareholding; the issuer is state-owned or dual listed overseas. Overall, default information in the bond market transmits through common underwriters.

Beyond density: COVID-19 as an accelerator of spatial (in)justices

Around the end of 2019, in Wuhan, Hubei Province, China, the first confirmed cases of COVID-19 were identified, and from then on, the world we were used to knowing changed globally. The role of population density, in relation to the spread of the pandemic, has been widely scrutinised in urban studies, believed to be the triggering variable. However, the results so far are inconclusive. This paper suggests instead to shift the focus to socio-spatial vulnerabilities, as the effects of the pandemic's spread have been more severe in urban units which feature long-standing inequalities. The paper's aim is, therefore, twofold: on the one hand it aims at contributing to the debate on population density and COVID-19 in urban areas, and, on the other hand, to analyse the pandemic's spread in relation to socio-spatial vulnerabilities. Different cities across the globe are drawn into a comparative project, where the pandemic's spread is analysed in relation to variables of Population Density (PD) and a Social Vulnerability Index (SVI), by employing correlation matrices. The results suggest that there is no significant correlation between density and the spread of COVID-19. Instead, a positive correlation is in place when analysing the pandemic's diffusion with socio-spatial inequalities.

The effect of tumor spread through air spaces on the prognosis of patients with stage Ⅰ non-small cell lung cancer: a meta-analysis

Objective: To systematically evaluate the effect of tumor spread through air spaces (STAS) on the prognosis of patients with stage Ⅰ non-small cell lung cancer (NSCLC). Methods: PubMed, Embase, Web of Science, Cochrane Library, CNKI, Wanfang Database and VIP were searched to collect papers related to NSCLC and STAS published from the establishment of aboves databases to November 2022. Papers were screened according to the inclusion and exclusion criteria, and data were extracted. The 5-year overall survival (OS) and relapse-free survival (RFS) of stage Ⅰ NSCLC patients with or without STAS were compared. HR(95%CI) was used as effective indicator to evaluate the impact of STAS positivity on the prognosis of NSCLC. The quality of each included study was assessed using the Newcast-Ottawa Scale (NOS). Results: A total of 24 papers concerning 29 studies were included according to the inclusion and exclusion criteria, and there was no significant heterogeneity among the included papers(all I2<50%). A total of 10 883 patients with stage Ⅰ NSCLC were included in the studies, of which 3 298 (30.3%) were STAS-positive. The 29 studies showed that STAS-positive patients had a higher risk of 5-year recurrence than STAS-negative patients with stage Ⅰ NSCLC [HR=1.94(95%CI:1.74-2.16)];and a meta-analysis of 17 of the studies showed that that STAS-positive patients had a higher risk of 5-year death [HR=2.09 (95%CI:1.80-2.43)]. Compared with stage Ⅰ NSCLC patients who underwent other surgeries, STAS-positive patients who underwent sublobar resection had a higher risk of 5-year recurrence than patients with other procedures (HR=3.44, 95%CI: 2.49-4.76) and a higher risk of 5-year death (HR=3.40, 95%CI:2.05-5.64); and patients with stage Ⅰ NSCLC who had the pathologic histologic type of squamous carcinoma had a higher risk of 5-year recurrence (HR=2.48,95%CI:1.71-3.60) and a higher risk of 5-year death (HR=3.04, 95%CI: 1.90-4.86) than other patients with the type of squamous lung cancer. Conclusion: STAS positivity is a risk factor of poor prognosis in patients with stage Ⅰ NSCLC, especially for patients underwent sublobar resection or with squamous lung cancer.

Thermal Simulations in GaN HEMTs Considering the Coupling Effects of Ballistic-Diffusive Transport and Thermal Spreading

Thermal Simulations in GaN HEMTs Considering the Coupling Effects of Ballistic-Diffusive Transport and Thermal Spreading

Cutaneous Anthrax of the lip: a Case Report in a 1 Year Old Infant

Anthrax is a deadly, contagious bacterial infection. Skin anthrax is most frequent. Anthrax is a work-related illness, so it’s rare among kids. Children’s symptoms are similar to adults. In this article, we introduce a one-year-old infant who developed cutaneous anthrax due to contact with contaminated broth with a sore on the corner of the lip. A 1-yearinfant from a village in Quchan, North-east Iran, with a swollen lesion with dark brown to black crust on its surface on the left side of upper lip presented to Akbar’s Children Hospital, Mashhad, Iran, in January 2021. Bacillus anthracis was seen in direct smear of wounds with Gram staining though the sample culture result was negative. Mortality from cutaneous anthrax can be up to 20%. Therefore, timely use of antibiotics is quite effective in decreasing mortality and reducing the effects of bacterial spread in the blood.

Impact of Spread Effect on Public Market Place (Lambaro Aceh Besar)

Aceh Besar Regency is the primary access and entrance gate to the provincial capital, directly adjacent to the city of Banda Aceh. This proximity positions Aceh Besar as a buffer from the city. The strategic location and position make Aceh Besar an opportune area for rapid growth and development. Thus, developing these strategic areas will foster the emergence of growth centers (Growth Poles). This research aims to determine and analyze the impact of the spread effect on the public market between Aceh Besar Regency and Banda Aceh City as a potential sector that can encourage economic growth and have a spreading effect on the surrounding area. The analysis method employed in this research is a quantitative approach utilizing descriptive analysis. The results of the research show that the results of the gravity analysis of sub-districts in Aceh Besar Regency and Banda Aceh City show that Want Jaya Sub-district as the primary growth center has the greatest interaction value with Darul Imarah Sub-district. The last sub-district is one of the sub-districts in Aceh Besar Regency with an interaction value of 76,525,776,000. Furthermore, the largest interaction values after Darul Imarah District are Krueng Barona Jaya District and Montasik District with interaction values of 15,062,514,047 and 11,831,506,347 respectively.