Volume 15 ~ Issue 3

This study undertakes a rigorous techno-economic and environmental evaluation of hybrid renewable energy systems as a pathway to improving electricity supply in Salvation Ministries Cathedral, Igwuruta, Rivers State, Nigeria, an area typified by acute rural energy deficits. Drawing upon high-resolution meteorological datasets from NASA and the Global Wind Atlas, the analysis examines the viability of an integrated system comprising solar photovoltaics, wind energy, battery storage, and diesel generation within an optimized microgrid framework. Advanced modeling platforms including HOMER Pro for economic optimization and ETAP 19.0.1 for transient electrical performance are employed to simulate alternative configurations under representative load conditions and climatic realities.......
Keywords:- Hybrid renewable energy, Microgrid, Solar PV, Wind turbine, Techno-economic analysis, HOMER Pro, ETAP, Net Present Cost, Levelized Cost of Energy, Weibull distribution, Grid integration, Distributed generation.

To reveal the spatiotemporal evolution characteristics of surface water bodies in the eastern high groundwater level mining areas, this paper takes Yanzhou Coalfield as the research area. Four commonly used water extraction methods, including the modified normalized difference water index (MNDWI) method, single-band threshold method, spectral relationship method, and K-T transformation method, were compared in terms of extraction accuracy and advantages and disadvantages. Based on the comparison results, the MNDWI method based on threshold segmentation was selected to extract water body information from 2015 to 2022, and its spatiotemporal variation characteristics were analyzed.......
Keywords:- Yanzhou Coalfield; coal mining subsidence; modified normalized difference water index (MNDWI); water area dynamic monitoring; driving force analysis.

Digital learning resources have become a strategic component of higher education, especially in open, blended and distance learning environments. However, many institutions still treat digital resources as digitized documents rather than as structured, interactive, measurable and reusable learning systems. This paper proposes a technology-supported management model for organizing the production, deployment, evaluation and continuous improvement of digital learning resources in higher education. Based on applied research and institutional implementation analysis, the study synthesizes theoretical foundations, practical requirements, production workflows, quality criteria and governance mechanisms for digital learning resources.......
Keywords:- Digital learning resources; learning management system; distance education; higher education; educational technology; learning analytics; quality assurance.

This article presents the design, implementation, and initial evaluation of an artificial-intelligence-enabled chatbot for academic advising and training management in a university distance-learning context. The study addresses a practical management problem: distance learners often need timely, accurate, and personalized answers about regulations, curricula, credit registration, learning progress, assessment, and graduation conditions, while academic advisors face high volumes of repetitive inquiries during peak periods........
Keywords:- Academic advising; distance education; chatbot; retrieval-augmented generation; training management; vector database; relational database; learning support.