Cotton fiber-reinforced polymer composites have emerged as promising sustainable structural materials. However, the combined influence of fiber volume fraction ($V_f$) and fiber orientation on their mechanical performance has not been fully quantified. In this study, the mechanical behavior of cotton fiber-reinforced epoxy composites containing fiber volume fractions ($V_f$) of 20 vol.%, 40 vol.%, and 50 vol.% was systematically investigated through finite element analysis using ANSYS. Two representative reinforcement architectures, namely unidirectional and tri-directional fiber orientations, were modeled to evaluate their responses under tensile, flexural, and compressive loading conditions. The mechanical performance was assessed to elucidate the reinforcing mechanisms associated with different fiber configurations. It was found that the mechanical properties were consistently enhanced as the fiber volume fraction increased. Among all configurations, the composite containing 50 vol.% fiber volume fractions with a tri-directional orientation exhibited the highest mechanical performance, achieving tensile, flexural, and compressive strengths of 57.67, 71.03, and 68.31 MPa, respectively, corresponding to improvements of 46.1%, 17.5%, and 16.1% over the 20 vol.% tri-directional composites. Similarly, the 50 vol.% unidirectional composite demonstrated increases of 43.4% in tensile strength, 15.2% in flexural strength, and 17.3% in compressive strength relative to the corresponding 20 vol.% unidirectional configuration. Superior mechanical performance was consistently achieved by the tri-directional architecture compared with the unidirectional counterpart, which was attributed to a more uniform stress transfer mechanism, reduced stress concentration, and improved load redistribution, as confirmed by the von Mises stress distributions obtained from the finite element simulations. These findings demonstrate that both fiber volume fraction and fiber orientation play critical roles in governing the mechanical behavior of cotton fiber-reinforced epoxy composites. The numerical results further indicate that optimizing reinforcement architecture can substantially improve structural efficiency while maintaining the inherent sustainability and lightweight characteristics of natural fiber composites, thereby supporting their broader application in environmentally responsible engineering structures. 20%, 40%, and 50%.

The financial sustainability of non-governmental organizations (NGOs) is potentially vulnerable to fluctuations in external financing, particularly in resource-constrained settings where continued access to funding may be uncertain. This study examined the relationship between external financing fluctuations and the financial sustainability of NGOs in Kakamega County, Kenya, drawing on Resource Dependence Theory (RDT). An explanatory research design was adopted, and a census approach was used to target all 69 registered NGOs in the county, of which 67 participated, yielding a response rate of 97.1%. Primary data were collected using semi-structured questionnaires and analyzed using Pearson’s correlation and linear regression in the Statistical Package for the Social Sciences (SPSS). A positive and statistically significant correlation was reported between external financing fluctuations and financial sustainability (r = 0.619, p < 0.05). Regression analysis also indicated a positive association, with a reported unstandardized regression coefficient of B = 0.321. The regression model was reported to yield R = 0.836, R² = 0.699 and an adjusted R² = 0.680, suggesting that a substantial proportion of the observed variation in financial sustainability was accounted for by the predictors included in the model. These findings suggest that external financing dynamics are relevant to the financial sustainability of NGOs in Kakamega County. However, the direction and magnitude of this relationship should be interpreted in accordance with the operational definition of financing fluctuations and the specification of the regression model. The findings provide a basis for further investigation into how changes in external funding affect the financial resilience of NGOs and underscore the importance of examining financing patterns when assessing organizational sustainability.

Hard point-of-interconnection (POI) export limits can strand otherwise-available photovoltaic (PV) energy unless battery storage is dispatched with sufficient anticipation and under physically consistent constraints. This study evaluates a constraint-audited receding-horizon dispatch framework for curtailment recovery at an anonymized 230 MW utility-scale PV plant with a modeled 195.5 MW export cap and a nominal 30 MW/140 MWh battery energy storage system (BESS). The mixed-integer model predictive controller enforces BESS power and energy limits, charge–discharge exclusivity, no grid charging, forecast-dependent discharge headroom, first-action receding-horizon execution, and a common 50%-to-50% terminal-energy protocol. Twelve rolling monthly folds from September 2024 to August 2025 are evaluated against cap-only operation and a protocol-matched perfect-information Oracle. Cap-only operation curtails 26,279 MWh (4.9872% of evaluated PV energy). A transparent 72 h Diurnal model predictive control (MPC) reduces curtailment to 11,719.454 MWh, recovers 14,559.546 MWh, and closes 98.450% of the modeled cap-only-to-Oracle recoverable-energy opportunity; the matched Oracle curtails 11,490.175 MWh. All 3 h closed-loop trajectories satisfy the modeled export cap, BESS limits, terminal equality, charge–discharge exclusivity, discharge-headroom rule, and no-grid-import condition. A matched information-sensitivity analysis then compares History-CatBoost and Weather-CatBoost under the same controller. Weather-CatBoost lowers daylight mean absolute error (MAE) by 2.225 MW at 24 h and 1.175 MW at 72 h relative to History-CatBoost, while annual curtailment is 288.601 MWh higher at 24 h and 99.699 MWh lower at 72 h; the monthly block-bootstrap intervals include zero in both cases. Histogram gradient boosting (HGB) robustness and BESS-sensitivity results further show that the incremental control value of weather information is model- and configuration-dependent. Under the tested plant, cap, BESS, 3 h resolution, horizon, and terminal protocol, physically constrained anticipatory dispatch captures most of the modeled recoverable curtailed energy, leaving comparatively limited residual opportunity for additional forecast sophistication.

Marine diesel engines are major contributors to atmospheric pollution, emitting SO₂, CO₂, NOₓ, and CO in quantities subject to increasingly stringent International Maritime Organization (IMO) regulations. Wet scrubbers are a cost-effective exhaust gas cleaning option, yet most existing systems employ either immersion (dipping) or spray (shower) gas–liquid contact in isolation, and experimental data on a structurally combined dipping–shower contact pattern under marine diesel conditions remain scarce. In this study, the term “hybrid” denotes this structural combination of bubble-immersion and spray contact, not the open-loop/closed-loop switching systems commonly called hybrid scrubbers in shipping. A prototype hybrid wet scrubber was fabricated from recycled industrial oil-storage drums and tested on a Dongfeng diesel engine at four engine-speed settings (25%, 50%, 75%, and 100% of rated speed). Concentrations of CO₂, SO₂, NO₂, and CO were measured at the scrubber inlet and outlet with an Internet of Things (IoT)-based multi-gas sensor node under three configurations: dipping-only, shower-only, and hybrid (dipping + shower), with five consecutive sensor readings per condition, and removal efficiency (η) was reported as mean ± standard deviation. Averaged over the four engine speeds, the hybrid configuration gave the highest removal of all four gases, with mean gains of about 6 and 10 percentage points for SO₂ and about 3 and 10 percentage points for CO relative to dipping-only and shower-only operation, respectively; it was not superior at every individual condition (e.g., CO at 100% and CO₂ at 75% of rated speed). SO₂ achieved the highest removal (75–79% in hybrid mode, coefficient of variation below 7%), and CO peaked at 78% at 25% rated speed, declining at higher speeds because of reduced gas–liquid contact time. By contrast, CO₂ removal remained inherently limited (8–11%) owing to its low aqueous solubility, and NO₂ removal was below 10%, reflecting the poor water solubility of NO that dominates NOₓ. The overall efficiency trend was SO₂ > CO > CO₂ > NO₂. These results indicate that the hybrid dipping–shower scrubber is best regarded as a low-cost, transitional emission-control device suited mainly to SO₂ and partial CO abatement; it cannot meet deep CO₂ capture or stringent NOₓ-control requirements without alkaline absorbents, oxidants, or multi-stage treatment. Future work should address chemically enhanced scrubbing liquids, repeated long-duration testing, and characterization of the wash water to manage the risk of transferring pollution from air to water.

The institutional processes through which public debt audit findings are translated into corrective action remain insufficiently understood, particularly where fragmented administrative records and fiscal stress coexist with established debt-reporting practices. This study examines the evolution of public debt reporting in Ghana between 2016 and 2025 and traces the institutional response to a substantial discrepancy identified in the Auditor-General’s 2024 Whole-of-Government Accounts (WGA). A longitudinal embedded single-case study design was employed, combining systematic coding of Annual Public Debt Reports (APDRs) across eight disclosure domains with process tracing of the subsequent institutional response. Debt indicators were examined to contextualise the findings rather than to establish a causal relationship between audit intervention and fiscal outcomes. The analysis shows that annual debt reporting became an established practice, accompanied by broader disclosure of debt portfolio characteristics, costs, risks, guarantees, on-lending and contingent liabilities. Nevertheless, a GH¢138.91 billion difference was reported between the debt balance consolidated by the Controller and Accountant-General’s Department (CAGD) and the corresponding Ministry of Finance record. Subsequent parliamentary scrutiny indicated that a substantial part of this discrepancy arose from differences in consolidation boundaries, following which the institutions reconciled their figures. This sequence illustrates how an audit finding can progress through detection, disclosure, deliberation and correction, although limited publicly documented evidence was identified of sustained improvements in preventive controls. Meanwhile, Ghana’s debt-to-GDP ratio increased from 56.8% in 2016 to approximately 80% in 2020 before declining to 44.7% by the end of 2025, providing fiscal context without demonstrating that audit contributed to these changes. An Audit–Accountability Transmission Mechanism (AATM) is developed to distinguish the identification of audit findings from their institutional uptake and potential governance consequences. The framework highlights inter-agency reconciliation, parliamentary scrutiny and recommendation follow-up as critical mechanisms through which audit findings may be translated into corrective action and institutional accountability. The findings also demonstrate the importance of distinguishing discrepancies arising from different reporting boundaries from errors in underlying debt records. Effective public debt oversight therefore requires not only transparent reporting and independent scrutiny but also documented reconciliation procedures, traceable corrective actions and verifiable improvements in preventive controls.