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Recent Submissions

MULTI-OBJECTIVE INTEGRATED APPROACH FOR DISTRIBUTED GENERATION PLACEMENT AND SIZING TO ENHANCE PERFORMANCE OF RADIAL POWER DISTRIBUTION SYSTEM
(Vysoká škola báňská - Technická univerzita Ostrava, 2025) Ranga, Jarabala; Jalli, Ravi Kuma; Muthusamy, Senthil Kumar; Sundaresan, Vijayalakshmi; Ramesh, Sundar; Palanisamy, Rajakumar; Aralprakusam, Sakthidasan
This article proposes an integrated approach combining a novel population-based jellyfish search al- gorithm (JSA) and loss sensitivity factor (LSF) to optimize single and multiple distributed generation (DG) placement and ratings for total active power loss (TAPL) minimization and total voltage deviation (TVD) reduction. The study considers photovoltaic (PV) and wind turbine (WT) DG systems for optimal integration. The simulation findings are examined for a single and multiple DG allocation on the IEEE 69-bus benchmark radial distribution power network (RDPN). The TAPL of the 69-bus benchmark RDPN is mini- mized from 225 kW to 77.10 kW, 62.32 kW, 19.52 kW, and 9.94 kW after the single PV, three PV, single WT, and three WT DG systems optimization, respectively. Simultaneously, the TVD is minimized from 1.8369 per unit (p.u.) to 0.7036 p.u. and 0.6698 p.u. for a single and three PV DG systems optimization, respectively, and 0.3934 p.u. and 0.3466 p.u. for a single and three WT DG systems placement, respectively. The perfor- mance of the proposed integrated approach is compared to the different optimization techniques, taking TAPL as a comparison metric. The comparison showcases that the integrated approach results in a favorable op- timal solution among the compared optimization tech- niques.
Enhanced Reservoir Characterization of Phem Field, Offshore Niger Delta: Integration of Seismic Attributes and Reservoir Property Modeling
(Vysoká škola báňská-Technická Univerzita Ostrava, 2025) Salami, Rotimi; Adepetun, Adeolu Oluwafemi
This study provides a comprehensive characterization of hydrocarbon-bearing reservoirs in the Phem Field, offshore Niger Delta, integrating well logs, seismic attributes, and petrophysical modeling for enhanced exploration and production. Three key reservoirs (R-1, R-2, and R-3) were identified within the Agbada Formation, exhibiting intercalated sand and shale layers with variable thickness and significant hydrocarbon potential. Well log analyses based on gamma ray (GR), resistivity, and neutron-density (N-D) logs revealed increasing shale content with depth, aligning with the stratigraphy of the Agbada Formation. Time and depth structure maps highlighted key structural features and hydrocarbon trapping mechanisms, supported by fault-controlled anticlinal structures. Seismic attribute analysis, particularly RMS amplitude and average envelope, delineated high-amplitude zones correlating with high- porosity sands and favorable reservoir facies, providing strategic targets for exploration. Petrophysical modeling, including net-to-gross (NTG), porosity, and permeability models, confirmed superior reservoir quality in specific zones, with NTG values reaching 95% and porosity ranging from 0.12 to 0.42. Additionally, water and hydrocarbon saturation models underscored zones with strong hydrocarbon presence and minimal water content, marking promising areas for efficient hydrocarbon recovery. These integrated findings highlight the Phem Field's robust hydrocarbon potential, offering valuable insights for optimized reservoir management and future development.
Geophysical and Geotechnical Investigation, and Lime Stabilizing Effect on Subgrade Failure Around a Section of Lagos-Abeokuta Highway
(Vysoká škola báňská-Technická Univerzita Ostrava, 2025) Ojekunle, Olurotimi Victor; Omitogun, Solomon; Oloruntola, Moroof O.
An electrical resistivity survey and geotechnical investigations were employed to examine the factors responsible for incessant roadway failure along sections of the Lagos-Abeokuta highway in Southwestern Nigeria. A study on the efficacy of lime as a stabilizing agent on failed subgrade soil was also conducted. Electrical resistivity imaging and laboratory geotechnical tests with the aid of grain size analysis, Atterberg’s limits, the standard proctor compaction test, the CBR (unsoaked and soaked), and the compression test (UCS) were carried out for this study. The 2D resistivity images reveal incompetent subgrade layers with resistivity values ranging between 12– 88.3 Ω.m, and values ranging between 21.5 and 127.3 Ω.m at a depth of approximately 2 m for the VES investigation. The laboratory geotechnical tests’ results along the failed segments also reveal poor subgrade soils which are composed of clay, clayey sand, and sandy clay; with plasticity indices ranging between 29.4 and 31.5, and average values of 74.5 KN/m2 and 1.69 g/cm3 for the UCS and maximum density, respectively. However, with lime admixture to the soil samples in 2%, 4%, 6%, 8%, and 10% proportions, there was a progressive improvement in the shear strength of the clayey soil samples, owing to the reduction in the plasticity and increase in the MDD and UCS.
D6.2 : Demonstration of the TERRAVIEW Application Case
(2025-10-31) Bogdanov, Evgeny; Gutta, Kiran; Teran, José; Chaudhary, Smaran; Furmánek, Radek; Hachinger, Stephan; Ventsenostseva, Zhanna; Öztürk, Aslı Umay
This deliverable demonstrates the outcome of the SME/Smart - Viticulture application case of EXA4MIND. The work has focused on a Soil Moisture Content (SMC) monitoring system capable of processing large-scale satellite imagery to support viticulture. This “A quaview” platform is shown, assessed and validated. A central component of this endeavour is a rigorous benchmarking study that evaluates the efficiency of the EXA4MIND "Extreme Data" architecture against traditional data retrieval methods. EXA4MIND with its Advanced Query and Indexing System offers a continuously-updated satellite data cache for Aquaview via an iRODS object store. The performance of selective Cloud-Optimized GeoTIFF (COG) access via this cache is compared to legacy full-file downloads. The results demonstrate that the integrated solution achieves significant improvements in data ingestion speeds and substantial reductions in payload sizes. These findings validate the scalability of the Aquaview pipeline, confirming its readiness to address the critical water management challenges of the wine industry using infrastructure at supercomputing centres.
D3.3 : Query Performance Report
(2025-10-31) Gelecek, Atakan; Koç, Robin; KARAGÖZ, Pinar; Pauw, Viktoria; Ventsenostseva, Zhanna; Furmánek, Radek
The EXA4MIND project enables Extreme Data analytics, leveraging top-notch computing facilities and optimum data stores – from object stores over relational databases to NoSQL databases. EXA4MIND aims to facilitate data-flow connectivity between its database and object-storage deployments, computing systems at supercomputing centres, and the European data ecosystem (EUDAT, EOSC, European Data Spaces). In such demanding setting, using the databases efficiently and effectively is critical. Deliverable D3.3 presents how different types of databases and data storage systems are used in the Platform and Application Cases with a focus on improvement provided with the effective data management in the AQIS workflows. The obtained improvements are presented under two subtitles: (i) Functional Improvements, and (ii) Performance Improvements. The functional improvements describe the new functionalities provided to the Application Cases with the use of databases and database querying, whereas the performance improvements include the improvements obtained in comparison to previous status of the functionalities and services by the Application Cases with the integration of databases or tailoring the way databases are accessed and queried. The solutions we present are also applicable to a variety of other possible use cases.