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Neurodynamic analysis of NACA 0012 airfoil and wing using Bayesian regularisation
Full text linkThis paper proposes a novel neural network-based approach with Bayesian regularisation for analysing air foils and wings. Here, the established NACA0012 airfoil, a standard in aviation and aerospace engineering, is used. Empirical methods, various software, and computational fluid dynamics (CFD) simulations have been commonly employed in airfoil analysis. To forecast and model the aerodynamic characteristics of the NACA0012 airfoil and its wing counterparts, this study presents a data-driven approach utilising artificial neural networks (ANNs). Datasets are first generated using software xflr5, followed by AI-based Bayesian regularisation (AI-BR). Approximations in analyses were demonstrated using three data sets: training (80%), testing (10%), and validation (10%), with 20 neurons. Large-scale Simulink results on mean-squared error, error histograms, and regression analyses further emphasise the proposed AI-BR\u27s competence, dependability, and accuracy. A direct and immediate way to assess the accuracy of models or measurements is to use an absolute error (AE) plot, which shows the differences between estimated and actual values. The findings support the effectiveness of integrating ANNs with Bayesian regularisation in aerodynamic analysis. The approach not only enhances prediction accuracy but also opens new avenues for future investigations into more complex aerodynamic models
Multi-satellite analysis of key climate variables over Qinghai province: GNSS-RO vs remote sensing (2019–2023)
Full text linkReliable climate monitoring is essential for understanding environmental changes in sensitive regions such as Qinghai province, China, where complex topography and scarce ground observations challenge accurate assessment. In this context, GNSS-RO has emerged as a robust technique, offering high vertical resolution, global coverage, and long-term stability. This study conducts a comparative analysis of three key climate variables: air temperature, precipitation, and evapotranspiration in Qinghai from 2019-2023 using GNSS-RO alongside widely used satellite-based datasets, namely ERA5 for air temperature, GPM for precipitation, and TerraClimate for evapotranspiration. Results reveal notable discrepancies: remote sensing air temperatures (269.56–271.69 K) were consistently higher than GNSS-RO values (~263.2 K); TerraClimate evapotranspiration estimates (2,600– 2,734 mm) were substantially larger than GNSS-RO values (~500 mm/year); and GNSS-RO precipitation outperformed GPM with lower bias and RMSE (2.130 mm; 5.900 mm vs. 18.573 mm; 22.601 mm). These differences may reflect the influence of regional topography, atmospheric variability, and dataset-specific retrieval methods. Spatiotemporal variations were especially evident in high-altitude areas, underscoring GNSS-RO’s advantage in capturing mountain climate dynamics. Overall, the findings emphasise the need for integrating multiple satellite platforms to reduce uncertainties, strengthen climate monitoring in data-scarce regions, and provide more reliable evidence for climate policy and future adaptation strategies
Optimizing wettability alteration in carbonate reservoirs using hybrid low saline brine formulations for enhanced oil recovery
Full text linkThe study explores the effects of hybrid low-saline brine (LSB) formulations on wettability alteration to promote oil displacement efficiency in carbonate reservoirs. It addresses the challenges of shifting rock surfaces from oil-wet to water-wet conditions, particularly in high-salinity, and temperature environments. Five hybrid LSB injection schemes were designed, incorporating different salts, xanthan polymer, silica nanoparticles, and reef salts to improve wettability alteration in carbonate cores. The Fourier Transform Infrared spectroscopy (FTIR), revealing significant changes in mineralogy, and surface structure. Contact angle (CA) measurements were performed to evaluate the impacts of modified LSB on carbonate cores, signifying that rock-brine-oil interactions potentially altered the surface chemistry, shifting wettability from oil-wet to water-wet. The findings reveal that higher salinity and temperature improved the wettability shift, decreasing CA from 126° to 80°. Scheme 5, containing silica nanoparticles, reef salts, and xanthan polymer, significantly altered surface alkalinity and wettability by reducing CA over 30° at 60°C. This indicates that higher salinity and temperature in LS brine enhance wettability alteration and decrease interfacial tension, substantial for efficient oil recovery. The study confirms the usefulness of hybrid LSB formulation in wettability alteration, advancing enhanced oil recovery (EOR) techniques in carbonate reservoirs, under complex conditions
New records of spiders: Araneae, Pisauridae, Salticidae, and Theridiidae from Pakistan
Full text linkThe genus Emertonella Bryant, 1945, with Emertonella taczanowskii (Keyserling, 1886), is recorded for the first time with stable random population distribution, extension of Chinattus mikhailovi Logunov, 2021 towards the southern part with clump pattern of distribution of population, and Perenethis sindica (Simon, 1897) recorded after 127 years with stable random pattern population distribution from the subtropical to the ecotone of the North-West Hindu Kush Peshawar valley, eurytopic species Loxosceles rufescens (Dufour, 1820) reported extended distribution from the subtropical to the Pan Hindukush-Himalaya mountains sub-temperate regions. We observed that synanthropic pressure is due to anthropogenic extension displacing or changing the behavioural ecology of these spiders. The authors point out the adverse effects of human activities, such as habitat destruction and agriculture, which threaten local wildlife and biodiversity. They stress the urgent need for more studies on spiders in Pakistan to fill the gaps in our understanding of the distribution of species in Eurasia. The research involved actively collecting specimens and closely examining them better to understand the patterns in their distribution and ecological roles. The findings call for conservation efforts in the biodiversity-rich Hindu Kush region of Pakistan
Enhancing peacekeeping deployment: structural and functional reforms from Rwanda and South Sudan case studies
Full text linkUnited Nations Peacekeepers endeavour to prevent the recurrence of violence and establish conditions conducive to enduring peace in countries ravaged by conflict. This document analyses methods to enhance the deployment and organisational structure of UN Peacekeeping missions, utilising two missions as illustrative case studies. It underscores the significance of the mission mandate, elucidating how it can facilitate support to peacekeepers during deployment rather than impede their efforts, and outlines the process for implementing necessary modifications. The study commences with an overview of UN peacekeeping and proceeds by providing background information on the missions in South Sudan and Rwanda, both serving as case studies. The central section investigates strategies for bolstering peacekeeping efforts, with an emphasis on the mission mandate and the deployment of peacekeepers. The case studies underscore the urgent necessity for reform in both the deployment and organisation of peacekeeping operations, notwithstanding some successes in mandate achievement. Although peacekeeping possesses substantial potential as a mechanism for restoring stability, its overall effectiveness remains constrained by existing deployment procedures and operational limitations. To address these issues more humanely and decisively in complex conflict scenarios, future missions must endeavour to surmount these challenges
Impact of temperature and precipitation variability on the sowing time and pest incidence on late-season gourd in Pakistan
Full text linkPakistan is an agricultural country where most people work in the agriculture sector. However, Pakistan’s agriculture industry is being severely impacted by climate change. This study examines the effects of temperature, precipitation, and pest incidence on late-season gourd crops, focusing on the districts of Mardan and Charsadda. Time series data were obtained from Khyber Pakhtunkhwa’s Meteorological Office, while cross-sectional data were gathered by survey questionnaires in the research area. Statistical analysis was used to evaluate the effects of temperature and precipitation on the variability of sowing dates and its subsequent impact on the frequency and growth of pests. Temperature rose by 0.15°C/year in Mardan and 0.1°C/year in Charsadda, while rainfall dropped by 1.4 mm/year and 0.9 mm/year, increasing pest damage to 79% and 75%, respectively. The findings indicate that farmers postpone sowing the gourd crop from the first to the last week of September to protect their crops from insect attacks and other damage. This is because the climatic factors (temperature and precipitation patterns) are changing. The primary pest causing significant harm to the gourd crop is the white fly, which spreads the virus known as mosaic viral disease. It is advised to offer heat-tolerant types with a brief lifespan
Investigating the role of green infrastructure for planning flood resilient cities: a case study of Peshawar, Pakistan
Full text linkRapid urbanisation and the worsening effects of climate change are the primary causes of urban flooding, which is becoming an increasingly serious global issue. Flood risks have increased in developing countries due to deteriorating infrastructure, intensifying precipitation, unchecked urban growth, and ineffective stormwater management. Major Pakistani cities, such as Peshawar, experience urban flooding, which damages infrastructure, disrupts the economy, and negatively affects livelihoods. Using Khamosh Colony as a representative example of one of the urban flooding hotspots, this study explores how Green Infrastructure (GI) can enhance urban flood resilience in Peshawar. The effectiveness of both standalone and combined GI interventions in addressing floods under rainfall events with a 5-year return period was simulated using the Storm Water Management Model (SWMM). While community preferences were gathered through surveys conducted using the Kobo Toolbox platform with over 400 respondents, economic feasibility was evaluated using MRS 2024. The most successful solutions were permeable pavement and a combination of permeable pavement and bioretention. This study provides stakeholders with a clear understanding of flood scenarios, both before and after GI implementation. This method encourages strategic investment in climate-resilient infrastructure and informs participatory planning
Evaluating the engineering design and computational analysis: a case study of Machai micro-hydropower plant, Mardan, Pakistan
Full text linkHydroelectric power generation is one of the most significant and dependable renewable energy sources for Pakistan. With a few minor adjustments and a range of design options, micro hydropower plants may be built on an existing canal to restore or boost irrigation water delivery and generate electricity by choosing the appropriate turbine. The design of the Machai hydropower plant was examined in this study using the Manning equation to establish the power canal\u27s design specifications. The Manning roughness coefficient is calculated to find the section factor. Hydraulic mean depth, top width, height, area, and channel width may all be determined using the section factor. Based on the outcomes of the TURBNPRO program, the Kaplan turbine installed in the powerhouse was selected. To evaluate the stability of embankments, SLIDE software was employed. The study concludes that micro-hydropower is a technically viable and environmentally friendly method of producing electricity in remote areas. Particularly for isolated off-grid locations, Machai and other micro-hydropower devices provide a cost-effective and ecologically friendly energy alternative. Compared to diesel generators or coal-fired power plants, micro-hydropower is a more environmentally beneficial choice since it emits no greenhouse gases when in operation
Reference pattern-based data aggregation in a wireless sensor network
No full textAdvances in computing hardware have enabled the development of wireless sensors that can detect and report various real-world phenomena in real time. These systems face bandwidth, power, and throughput limitations that restrict the amount of information transmitted end-to-end. Data aggregation is a proven method for addressing these issues. We employ reference pattern-based data aggregation in a wireless sensor network to save energy and reduce redundancy. In traditional data aggregation, each node sends its data to the cluster head, which combines it and forwards it to the base station, consuming more energy. However, in ESPDA, each sensor node creates a pattern code for the sensed data using a lookup table and then transmits it to the cluster head. Pattern codes represent sensed data and are compact. Generating pattern codes from a lookup table poses challenges: first, creating the table requires more computational resources; second, finding critical values in the interval also consumes computational resources and energy. The new proposed mechanism lowers the use of computational and energy resources. We utilized a reference-based approach to generate the pattern codes. Simulation results show that the proposed mechanism is more energy- and computation-efficient compared to ESPDA
The scale direct shear test effect on the shear strength characteristics of different sands in Lahore, Pakistan
Full text linkThe direct shear test is a widely used method for determining soil and material shear strength parameters. This study examines the impact of shear box size on the shear strength properties of poorly graded sands collected from Lahore, Pakistan. Sand samples were classified using the Unified Soil Classification System and tested at dry densities ranging from 1.601 to 1.825 g/cm3 using shear boxes with 60 mm, 100 mm, and 160 mm diameters. Tests were performed at a constant rate of 1.25 mm/min under normal stresses of 23.42, 35.76, and 48.11 kPa. Results indicate that increasing box size leads to higher cohesion and lower friction angles, while increasing soil density enhances both parameters. Regression relationships were developed to relate small-scale and large-scale test results. These findings underscore the importance of accounting for scale effects in laboratory shear testing and offer guidance on extrapolating small-scale results to design applications. The study highlights the significance of considering container size effects in the interpretation of laboratory shear tests. Future research may explore varying soil types and moisture contents to generalise these findings further. Understanding these scale effects is crucial for improving the accuracy of geotechnical assessments and ensuring safe construction practices