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Kalman Filter-Based Position Estimation in UAV Swarms: Impact of Swarm Size, Flight Paths and Onboard Sensors
No full textThis paper investigates swarm navigation performance for unmanned aerial vehicles (UAVs) under varying flight path geometries and swarm sizes. Employing both local and master Kalman filter (KF) estimation techniques, the study analyzes the accuracy and efficiency of each approach in estimating UAV positions. Simulations are conducted across a range of flight paths, from simple linear trajectories to more complex maneuvers, with swarm sizes ranging from small formations to larger groups, and with different sensors such as onboard cameras to measure attitude. The primary performance metric is position estimation error. A key focus of this study is understanding how attitude estimation, derived from an onboard camera mounted on the parent UAV, the quality of the parent UAV's gyroscope, and the number of child UAVs of the swarm influence both local and master KF performances. Results show that increasing the swarm size does not make position estimations better. However, adding attitude measurements and using a high quality gyroscope on the parent UAV significantly improves position accuracy. This research contributes to the development of robust swarm navigation algorithms for UAVs for applications such as coordinated surveillance, search and rescue operations, and collaborative payload delivery
A study of single secret leader election protocol constructions for robust proof of stake consensus
No full textA Dialectical Materialist Approach to Climate Justice: Akbelen Forest and Deştin Cement Factory Movements in Muğla
No full textThis article explores how a dialectical materialist approach enriches climate justice analysis by examining the contradictions between capital accumulation, labor, and nature. While conventional climate justice frameworks emphasize equitable outcomes and participatory governance, a dialectical materialist perspective delves deeper into the structural underpinnings of ecological degradation, linking environmental harm to capitalism's historical and material dynamics. By examining two case studies from Muğla, Türkiye, with empirical evidence collected from the field–the Akbelen movement against coal mining and the Deştin movement against cement factory construction–this article demonstrates how a dialectical approach reveals the systemic contradictions in climate justice analysis, historicizes ecological disparities, and questions the material basis of climate injustices. The study emphasizes the interconnectedness of environmental protection, class differentiation, and socio-economic emancipation. The findings contribute to environmental and climate justice scholarship by showcasing the analytical utility of dialectical materialism and shedding light on grassroots resistance in the Global South
AN EXACT DIAGONALIZATION STUDY OF A RAPIDLY ROTATINGBOSE-BOSE MIXTURE WITH ATTRACTIVE INTERACTIONS
No full textA Fuzzy-Fault Tree and Simulation-Based Approach for Evaluating Uncertainties in Haul Road Quality
No full textHaul roads are vitalcomponents of surface mining operations, directly impacting safety, production efficiency,and operational continuity. However, these roads are often constructed based onpractical experience rather than standardized methodologies, increasingvulnerability to failures under uncertain conditions. This study aims toconstruct a systematic framework to evaluate quality of haul roads in surfacemines, called Mine Road Quality Index (MRQI).The research focuses onidentifying and evaluating seventeen critical uncertainties categorized under fivedomains: structural design, functional design, management, geometric design,and geology. To quantify these uncertainties, an expert survey was designed.The responses were evaluated linguistically and then converted into fuzzynumbers. These fuzzy values were further processed using a fuzzy logicintegrated fault tree analysis (FFTA), enabling prioritization of uncertaintyfactors based on failure probability and criticality index. The developed modelwas tested using a hypothetical dataset to highlight how the model can beutilized. The results revealed that uncertainties such as presence of clay weremost likely to induce road failures. The FFTA output was then embedded into adiscrete event simulation (DES) model to simulate dynamic failure occurrencesover time. The outcomes of this hybrid approach provide promising groundworkfor future development of a standardized road quality index for surface mines.</p
Preservice teachers’ formative assessment strategies they intend to implement in a real classroom.
No full textIt Takes a Village: Housing Pedagogy in Disadvantaged Transitional Landscapes
No full textThe village, both as a physical entity and as a conceptual model, has been reconfigured within the urban fabric— sometimes as relics of a bygone era, sometimes as marginalized enclaves within the sprawl. This transformation, shaped by the relentless growth of cities, prompts reflection on how traditional, landscape-embedded set- tlements encounter contemporary processes of urbanization and socio-economic fragmentation. This paper presents a pedagogical experiment developed within an undergraduate architecture studio, which takes a peri-urban territory as its ground of analysis. Situated at the intersection of rural memory and urban expansion, the site presents a landscape in flux, where remnants of village life, informal housing, gated communities, and speculative developments coexist. The studio became a space to critically explore the socio-spatial entanglements of this rural-urban interface. Students were encouraged to interpret the village not as a romanticized artifact but as a living spatial model capable of informing socially cohesive and contextually grounded housing strategies. This prompted engagement with two diverging socio-economic models: one rooted in communal reciprocity; the other, in privatized development and fragmentation. Through site visits, mapping, and design research, students examined how housing becomes a site of negotiation between inherited spatial logics and new urban pressures. Their proposals drew from rural typologies— incremental growth, landscape embeddedness, and collective life—to imagine housing alternatives attuned to affordability, inclusion, and spatial justice. The studio offers a place-based, qualitative approach to housing pedagogy rooted in the lived complexities of transitional urban geographies.</p
From Wet to Dry: Climate-Driven Water Level Oscillations Amplify Nutrient Accumulation and Chlorophyll-a Response in Shallow Lakes
No full textThe functioning of shallow lakes, which are extremely susceptible to variations in precipitation, evaporation, and water inflows and outflows due to their shallow form, depends heavily on hydrology. Water level changes in shallow lakes have large impacts on the physical and biological features of these ecosystems, and water chemistry; nutrient processing and nutrient retention. The Mediterranean region, characterized by warmer and dry conditions, is experiencing increased evaporation and fewer wet days due to the effects of climate change. Here, we investigated the relationships between lake nutrient and chlorophyll-a (Chl-a) concentrations in Eastern Mediterranean Lakes Mogan and Eymir in the semi-arid climate overall and in dry, mid and wet periods of long-term monitoring. We hypothesised that; (i) high alteration in water levels between dry and wet periods will be observed due to semi-arid climate in the region, (ii) external loadings will play an important role on the in-lake nutrient concentrations, (iii) hydraulic retention time (HRT) will be affected on in-lake concentrations because longer the HRT higher the water column-sediment interactions and increase the internal phosphorus loading, and (iv) increasing temperatures will increase the Chl-a concentrations especially in dry periods due to more profound effects of stratification which triggers internal phosphorus loading. We further included PCA plots to determine the relationships between Chl-a and nutrient concentrations, temperature, external loading, HRT, depth, macrophytes and fish. 28-year mass balance analysis of two shallow, semi-arid lakes yielded the following primary outcomes: (1) variability between the dry and wet periods was high showing the risk of drying out of the lakes under the less precipitation and higher evaporation future of semi-arid Mediterranean lakes, (2) even with modest external loading, the nutrient concentrations during dry periods increased with nutrient accumulation from evaporative water loss especially in Lake Mogan, (3) Chl-a concentrations were affected mainly by temperatures in Lake Eymir where cyanobacteria blooms occur during summers most likely causing by more frequent thermal stratification and increased internal loading. These results enhance the understanding of how variations in hydraulic loading, water level, and hydraulic residence time influence nutrient and chlorophyll-a concentrations in shallow, semiarid lakes under both dry and wet conditions.</p
