Recent Submissions
Impact of Political Corruption on International Tourism Demand: A Panel Data Analysis of 22 Asian Countries
(University of Nigeria Department of Mass Communication, 2026-06-01) Weerasinghe, P; Bandara, C; Indrapriya, A; Jayasekara, K; Yapa, S.R; Dayapathirana, N
Background: Tourism serves as a critical driver of international economic activity, particularly for developing nations that rely on the sector for employment generation and foreign exchange earnings. However, tourism performance varies significantly across jurisdictions, suggesting that institutional factors, such as political corruption, may play a decisive role in shaping industry outcomes. Objective: This study investigates the impact of political corruption on tourism demand across Asia. Specifically, it seeks to determine whether, and to what extent, corruption levels significantly deter international tourist arrivals in these countries. Methodology: Adopting a quantitative research design, the study utilises panel data analysis covering 22 Asian countries from 2002 to 2020. Simple linear regression models were employed to examine the relationship between political corruption indices and international tourism demand. Results: The findings reveal a statistically significant negative relationship between corruption and tourism demand. The regression analysis demonstrates that higher levels of perceived corruption are associated with a marked decrease in tourist inflows. Although the model exhibits relatively low explanatory power, the consistency and significance of the negative effect indicate that corruption is a critical institutional determinant of tourism performance. Conclusion: The study concludes that political corruption is a major deterrent to the growth of the tourism industry. Reducing institutional uncertainties and curbing corrupt practices are essential prerequisites for countries aiming to enhance their competitiveness and attract international visitors. Unique Contribution: This research contributes to the intersection of governance and tourism literature by providing long-term empirical evidence from the Asian context. It highlights the importance of institutional quality as a primary factor in the patterns of international tourism flows. Key Recommendation: Governments and policymakers in the Asian region should prioritise anti-corruption reforms as a strategic tool for tourism development. Strengthening institutional transparency and reducing political risks will create a more favourable environment for international travellers and foster sustainable economic growth.
SLIF-Tomato: Inverted Residual Convolutional Block Attention Module for In-field Tomato Leaf Disease Recognition
(Springer Science and Business Media Deutschland GmbH, 2026-06-27) George, R; Thuseethan, S; Ragel, R.G; Pakeerathan, K; Sivalingam, V; Mithuran, T
Tomato cultivation represents a critical component of nutrition, economic development, and public health, yet it is increasingly compromised by foliar diseases that diminish yield and intensify dependency on hazardous agrochemicals. Although deep learning models have demonstrated strong capabilities for automated disease recognition, existing benchmark datasets exhibit limited real-world utility, primarily due to the absence of in-field imagery and precise annotations of diseased regions. A novel attention mechanism, Inverted Residual Convolutional Block Attention Module (IR-CBAM), is proposed, combining inverted residual blocks with the CBAM Module, and is specifically tailored to address challenges posed by in-field image variability, such as complex backgrounds and inconsistent lighting. Furthermore, this study introduces SLIF-Tomato, the Sri Lankan In-Field Tomato leaf disease dataset, which is the first complete in-field dataset comprising class labels and bounding box annotations collected under diverse real-world conditions. The proposed approach achieved 99.66% and 99.91% accuracy rates on two curated versions of the SLIF-Tomato dataset. Subsequently, the YOLOv12-large model is employed to detect diseased regions, which obtained an average precision score of 88.5%. These contributions advance the development of accurate, efficient and field-adaptable diagnostic systems for tomato leaf disease management in precision agriculture.
Investigating the mechanical and durability properties of locally sourced fly ash-based ternary cement paste to increase OPC replacement
(Emerald Publishing, 2026-07-07) Gamage, O; Kulasuriya, C; Perera, S V T J
The mechanical and durability performance of fly ash (FA)-based ternary blended cement pastes was investigated in an attempt to increase ordinary Portland cement (OPC) replacement while maintaining comparable strength and improved durability. This paper provides region-specific experimental data using locally sourced FA from Sri Lanka and imported ground granulated blast-furnace slag (GGBFS). A control mix (100% OPC), two binary blends and six ternary blends were tested for compressive strength at 3, 7 and 28 days, along with water absorption and resistance to sulfuric acid after 28 days. The results showed that OPC specimens achieved the highest early strength, while ternary blends with 25% and 40% OPC replacement achieved comparable 28-day strengths of 82.7 ± 4.8 MPa and 76.2 ± 3.2 MPa, respectively. GGBFS contributed to early strength gain, whereas FA enhanced long-term strength. Durability was improved significantly in the ternary blends. The F15S10 blend, with a higher GGBFS content, showed the greatest sulfuric acid resistance (4.8 ± 0.15% weight loss), while the F40S10 blend, with higher FA content, exhibited the lowest water absorption (6.0 ± 0.18%). Overall, ternary blends with 40% OPC replacement and low FA content are recommended for achieving balanced strength and superior durability in cement paste applications.
Chitosan-Starch Biocomposite for Enhanced Curcumin Delivery: Kinetic Modeling of pH and Ionic Strength Responsive Release and Evaluation of Biological Efficacy
(American Chemical Society, 2026-07-21) Abeywickrama, L; Wijayawardana, S; Thambiliyagodage, C; Jayanetti, M
A drug delivery system composed of chitosan and starch was used to deliver curcumin effectively by enhancing its pharmacokinetic properties. The sustained release of the synthesized delivery system was evaluated using a kinetic modeling approach along with its biological efficacy. The SEM analysis confirmed the coupling of starch and chitosan and loading of curcumin into the matrix during synthesis. Crystallographic orientation of the delivery system was confirmed by XRD, and the FT-IR data confirmed the successful loading of curcumin. TG analysis indicated that the increment in decomposition temperature of the composite is due to the incorporation of curcumin into the composite. BET analysis revealed the reduction in the BET surface area and pore volume in the synthesized composite, confirming successful loading. The IC50 values of the curcumin and composite for the DPPH assay were 17.81 μg/mL and 38.77 μg/mL, respectively. Composite material has shown enhanced antibacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa at 20 mg/mL, with inhibition zones of 15.56 ± 0.29 and 10.11 ± 0.44 mm, respectively. Allium cepa cytotoxicity assay confirmed that all the synthesized materials promote mitosis at 2.5 mg/mL concentration. The pH and ionic strength responsive release of curcumin was studied by fitting the release data into six kinetic models, including Korsemeyer–Peppas (KP) and Peppas–Sahlin (PS), which has not been reported earlier for the synthesized system. The KP and PS models were selected to interpret the release mechanism based on R2. A combination of Fickian diffusion, relaxation and swelling dominates the curcumin release. According to the KP model, quasi-Fickian diffusion is responsible for the release in acidic and alkaline pH, whereas non-Fickian diffusion occurs at pH 6.7. At higher [NaCl], relaxation is responsible for the release (n > 0.43, kD = 0), while a combination of diffusion and relaxation governs the release at lower [NaCl]. These behaviors are related to the chemical composition of chitosan and the release media, where the electrostatic repulsion, protonation and charge screening contribute to curcumin release.
Joint Resource Allocation and Network Slicing in Hybrid RF/VLC Systems: A Proportional-Fairness Approach
(Institute of Electrical and Electronics Engineers Inc., 2026-08-01) Rajahrajasingh, H; Jayakody, D. N. K.; Peha, J. M
This article presents a joint resource allocation and network slicing framework for hybrid radio frequency (RF) and visible light communication (VLC) systems based on a proportional-fairness (PF) objective. The proposed approach formulates a convex optimization problem that jointly allocates bandwidth resources across multiple slices and access technologies to balance aggregate throughput and user fairness. A relaxed PF solution is first derived via projected gradient optimization, followed by two practical rounding strategies: a simple threshold-based method and a greedy assignment heuristic that produce integer allocations with low complexity. Simulation results for a 20 MHz hybrid RF/VLC system (10 MHz/band) demonstrate that the proposed PF-based allocation achieves aggregate sum-rates of approximately 450-500 Mb/s with Jain's fairness indices greater than 0.9, thus outperforming static and rounding baselines by 10%-15% in throughput while maintaining high fairness. The analysis is further extended to asymmetric RF/VLC bandwidth conditions, demonstrating that the proposed PF-based slicing maintains high fairness while scaling throughput effectively. These results confirm that the PF formulation effectively captures the throughput fairness tradeoff and provides near-optimal slicing performance under realistic indoor bandwidth and power constraints.
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