Search Results (101)

The widespread adoption of the Internet of Things (IoT) has driven major advancements in wireless communication, especially in rural and suburban areas where low population density and limited infrastructure pose significant challenges. Accurate Path Loss (PL) prediction is critical for the effective deployment and operation of Wireless Sensor Networks (WSNs) in such environments. This study explores the use of Convolutional Neural Networks (CNNs) for PL modeling, utilizing a comprehensive dataset collected in a smart campus setting that captures the influence of terrain and environmental variations. Several CNN architectures were evaluated based on different combinations of input features—such as distance, elevation, clutter height, and altitude—to assess their predictive accuracy. The findings reveal that CNN-based models outperform traditional propagation models (Free Space Path Loss (FSPL), Okumura–Hata, COST 231, Log-Distance), achieving lower error rates and more precise PL estimations. The best performing CNN configuration, using only distance and elevation, highlights the value of terrain-aware modeling. These results underscore the potential of deep learning techniques to enhance IoT connectivity in sparsely connected regions and support the development of more resilient communication infrastructures. Full article

In recent years, the use of unmanned aerial vehicles (UAVs), commonly known as drones, has significantly surged across civil, military, and commercial sectors. Ensuring reliable and efficient communication between UAVs and between UAVs and base stations is challenging due to dynamic factors such as altitude, mobility, environmental obstacles, and atmospheric conditions, which existing communication models fail to address fully. This paper presents a multi-ray channel model that captures the complexities of the airspace network, applicable to both ground-to-air (G2A) and air-to-air (A2A) communications to ensure reliability and efficiency within the network. The model outperforms conventional line-of-sight assumptions by integrating multiple rays to reflect the multipath transmission of UAVs. The multi-ray channel model considers UAV flights’ dynamic and 3-D nature and the conditions in which UAVs typically operate, including urban, suburban, and rural environments. A technique that calculates the received power at a target UAV within a networked airspace is also proposed, utilizing the reflective characteristics of UAV surfaces along with the multi-ray channel model. The developed multi-ray channel model further facilitates the characterization and performance evaluation of G2A and A2A communications. Additionally, this paper explores the effects of various factors, such as altitude, the number of UAVs, and the spatial separation between them on the power received by the target UAV. The simulation outcomes are validated by empirical data and existing theoretical models, providing comprehensive insight into the proposed channel modelling technique. Full article

The Roma population is one of Europe’s largest ethnic minorities, often living in inadequate living conditions, worse than those of the majority population. They frequently lack access to essential services, even in high-income countries. This lack of basic services—particularly in combination with proximity to (stray) animals and human and solid waste—significantly increases environmental health risks, and leads to a higher rate of endoparasitic infections. Our study sheds light on the living conditions and health situation in Roma communities in Slovakia, focusing on the prevalence of intestinal endoparasitic infections across various settlement localisations. It highlights disparities and challenges in access to safe drinking water, sanitation, and hygiene (WASH) and other potentially disease-exposing factors among these marginalised populations. This study combines a comprehensive review of living conditions as per national data provided through the Atlas of Roma communities with an analysis of empirical data on parasitological infection rates in humans, animals, and the environment in settlements, applying descriptive statistical methods. It is the first study in Europe to provide detailed insights into how living conditions vary and cause health risks across Roma settlements, ranging from those integrated within villages (inside, urban), to those isolated on the outskirts (edge, sub-urban) or outside villages (natural/rural). Our study shows clear disparities in access to services, and in health outcomes, based on where people live. Our findings underscore the fact that (i) place—geographical centrality in particular—in an already challenged population group plays a major role in health inequalities and disease exposure, as well as (ii) the urgent need for more current and comprehensive data. Our study highlights persistent disparities in living conditions within high-income countries and stresses the need for greater attention and more sensitive targeted health-promoting approaches with marginalised communities in Europe that take into consideration any and all of the humans, ecology, and animals affected (=One Health). Full article

Soil has the ability to serve as a universal sink, meaning it may absorb contaminants from the environment. Additionally, plant leaves can also be used as indicators of environmental contamination. In our study, the bioaccumulation factor (BAF) was used to assess metal accumulation in the soil and leaves of the neem tree (Azadirachta indica) in Faisalabad, Pakistan. We analyzed the primary physical and chemical characteristics of the surface layer of soil in urban, suburban, and rural areas along an urbanization gradient. The ICP-OES technique was used to analyze the following elements: Ba, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Sr and Zn. The highest concentration of all elements was found in soil samples from urban areas, with an increasing tendency along with the urbanization gradient. A significant difference was found along the urbanization gradient on the plant leaves except for Cd, Cu, and Zn; a high level of pollution was measured for Ba, Pb, Co, Ni, Cr, and Cd in the urban area. We also calculated the bioaccumulation factor (BAF), but no clear pattern was found. Our findings show that high concentrations in soil do not always turn into higher plant uptake for plants. Our findings suggest that traffic and industrial emissions are likely the main cause of the metals in Faisalabad, because their concentration is higher than their background concentration. Our results also suggest that elemental analysis of soil and plant leaves is an appropriate indicator of environmental contamination. Full article

The built environment has been widely recognized as a critical determinant of physical activity among older adults. However, urban–rural disparities and the non-linear effects of environmental features remain underexplored. Using interpretable machine learning (random forest model) on nationwide representative data from 2526 older adults in the China Health and Retirement Longitudinal Study (CHARLS) database, this study identified both common and distinct risk factors for insufficient moderate-to-vigorous physical activity (MVPA) across diverse urban and rural contexts. The results revealed a location-based gradient in physical activity insufficiency: rural areas < suburban areas < central urban areas. Rural older adults faced greater constraints from safety concerns and transportation accessibility limitations. In comparison, urban older adults would benefit from targeted improvements in built environment quality, particularly elevator accessibility and diverse public activity spaces. Furthermore, non-linear relationships were observed between built environment features and physical activity, elucidating the “density paradox”: while moderate urban compactness promoted active behaviors, excessive density (>24,000 persons/km²), perceived overcrowding, and over-proximity to specific facilities (<1 km) were linked to reduced MVPA. These findings underscore the necessity for differentiated policy interventions in urban and rural settings to address the distinct environmental needs of older adults. Meanwhile, in urban planning, it is crucial that we balance spatial compactness and functional diversity within optimal thresholds for creating sustainable and inclusive built environments. Although a compact design may enhance mobility, equal attention must be paid to preventing spatial disorder from over-densification. Full article

Conducting research on the evaluation of rural resilience and risk governance strategies in the middle reaches of the Heihe River can provide a scientific basis for the sustainable development of rural areas in the inland river basins of arid regions. Affected by water resource constraints, the expansion of artificial oases, and excessive exploitation of groundwater, the rural areas in the middle reaches of the Heihe River Basin, the second largest inland river in the arid region of northwest China, are confronted with prominent contradictions in the human-land relationship and urgently need to enhance their ability to cope with risks. Based on the remote sensing data of land use and major socio-economic data, this study draws on the theory of landscape ecology to construct a disturbance-resistance-adaptability evaluation system. Taking Ganzhou District, a typical irrigated agricultural area, as a case study, the study uses the entropy weight method, resilience change rate, and obstacle degree model to analyze the rural resilience level and its changing characteristics from 1990 to 2020, identifies the key obstacle factors affecting the development of rural resilience, and proposes risk governance strategies accordingly. Main conclusions: (1) The overall rural resilience index is relatively low, showing significant spatial disparities. Towns with well-developed multifunctional agriculture, nature reserves, and ecological-cultural control lines have higher resilience indices. (2) The change rate of the rural resilience index demonstrates phase heterogeneity, generally undergoing a “relative stability-increase-decrease” process, and forming a differentiation pattern of “decrease in the north and increase in the south”. (3) Internal risks to rural resilience development in the Ganzhou District mainly stem from low economic efficiency, fragile ecological environment, and unstable landscape patterns, among which efficiency-dominant and landscape-stability obstacle factors have a broader impact scope, while habitat resistance-type obstacle factors are mainly concentrated in the western part and suburban areas. Enhancing the benefits of water and soil resource utilization, strengthening habitat resistance, and stabilizing landscape patterns are key strategies for current-stage rural resilience governance in the middle reaches of the Heihe River. This study aims to optimize the human-land relationship in the rural areas of the middle reaches of the Heihe River. Full article

Urbanization changes the environment through physical constructions, disturbances, and altered resource availability. These modifications influence both prey and predator assemblages. Several studies have indicated that hole-nesting birds outnumber ground nesters in cities. Differential nest predation can be one reason behind this observation. We conducted a multi-year artificial nest predation experiment along an urban gradient by using artificial ground nests and nestboxes in Rovaniemi, Finland. Because visually searching avian predators dominate in cities, we predicted that nest predation of ground nests will increase with urbanization, whereas nests in holes will be better protected than ground nests. Ground nest predation increased with urbanization, being lowest in forest and rural areas, intermediate in suburban area and highest in urban area. However, there was no year-effects on artificial ground nest predation, suggesting that even a single-year results of artificial nest predation experiment can be reliable. In the city, ground nest predation was greater than nestbox predation. In forests, nestbox predation was greater than ground nest predation. Among ground nests, predation was greater in the city than in forests. Among nestboxes, predation was greater in forest than in urban or suburban habitats. Only the ground nest predation was greater in managed than in un-managed parks. Ground nest predation decreased with tree cover and increased with the patch area. No variables were entered in the models of the nestboxes. The results indicated that ground nesters might avoid urban areas as nesting sites. We assume that visually searching avian predators benefit from the lack of covering vegetation in city parks. However, because most avian nest predators, like corvids, are not effective nest predators of hole-nesting birds, urban areas are safe nesting areas for hole-nesters. The results suggest that nest predation is one important factor that could explain, why hole-nesting bird species outnumbered ground-nesting species in cities. The result give support for the hypothesis that nest predation pressure can modify urban bird assemblage structure. Full article

With the intensification of aging, the imbalance between the supply and demand of elderly care services has become increasingly prominent. Taking Changsha as a case study, this research constructs an accessibility evaluation system based on the 15-min life circle theory, utilizing multi-source data. Spatial weighting characteristics of elderly care facility locations were analyzed through machine learning algorithms, and service coverage disparities between urban districts and suburban towns were assessed under 5-, 10-, and 15-min walking thresholds. Street view semantic segmentation technology was employed to extract street environmental elements in central urban areas, and a multiple regression model was established to elucidate the impact mechanisms of the built environment on walking accessibility. Key findings include: (1) Significant urban-rural service disparities exist, with 91.4% of urban core facilities offering seven service categories within 15-min walking catchments compared to 26.86% in township areas, demonstrating suburban infrastructure’s heavy reliance on administrative resource allocation. (2) Street environmental factors exhibit significant correlations with walking accessibility scores. At the 15-min walking threshold, building space ratio and transportation infrastructure coverage positively influenced walking convenience, while sky view ratio showed a negative correlation. (3) A random forest-based location prediction framework identified multiple service gaps in existing facilities. Suburban service deficiencies (e.g., 59.8% medical facility coverage within walkable catchments) emerge as critical equity barriers, prompting recommendations for integrated “micro-clinic + smart pharmacy” networks and prioritized mixed-use zoning in new urban planning. This research advances a data-driven framework for reconciling urbanization-aging conflicts, offering practical insights for developing nations in creating age-friendly urban environments. Full article

As a zone lying adjacent to urban areas, construction land development in suburbs includes urban expansion caused by urbanization and rural construction land increments caused by rural development. Given the necessity of satisfying urban and rural development demands while protecting the ecological environment, goals of land use efficiency, socio-economic coordination, and ecological benefit need to be ensured simultaneously, which indicates that the coordinative development of suburban construction land is of great significance, thereby raising the need for a reasonable evaluation for the coordinative level from multiple dimensions. However, the evaluation of suburban construction land coordination considering spatial, socio-economic, and ecological factors is insufficiently studied. To fill the research gap, this study comprehensively evaluates the coordination of suburban construction land at the town level. Specifically, four indicators from spatial, socio-economic, and ecological dimensions, including landscape pattern, accessibility, socio-economic symbiosis, and ecological functional suitability, are selected. By utilizing coupling coordination degree estimation, the coordination among the four selected indicators is evaluated. By adopting a case study of suburban Wuhan, different coordinative levels regarding suburban construction land development are identified and respondent suggestions to promote the coordination of suburban construction land under current China’s land use policies are provided. This study contributes to understanding the coordinative development of suburban construction land and proposing a method to estimate the coordination. Full article

Sustainable urban growth is an important issue in urbanization. Existing studies mainly focus on urban growth from the two-dimensional morphology perspective due to limited data. Therefore, this study aimed to construct a framework for estimating long-term time series of building volume by integrating nighttime light data, land use data, and existing building volume data. Indicators of urban horizontal expansion (UHE), urban vertical expansion (UVE), and comprehensive development intensity (CDI) were constructed to describe the spatiotemporal characteristics of the horizontal growth, vertical growth, and comprehensive intensity of the Beijing–Tianjin–Hebei (BTH) urban agglomeration from 2013 to 2023. The UHE and UVE increased from 0.44 and 0.30 to 0.50 and 0.53, respectively, indicating that BTH has simultaneously experienced horizontal growth and vertical growth and the rate of vertical growth was more significant. The UVE in urban areas and suburbs was higher and continuously increasing; in particular, the UVE in the suburbs changed from 0.35 to 0.60, showing the highest rate of increase. The most significant UHE growth was mainly concentrated in rural areas. The spatial pattern of the CDI was stable, showing a declining trend along the urban–suburb–rural gradient, and CDI growth from 2013 to 2023 was mainly concentrated in urban and surrounding areas. In terms of temporal variation, the CDI growth during 2013–2018 was significant, while it slowed after 2018 because economic development had leveled off. Economic scale, UHE, and UVE were the main positive factors. Due to the slowdown of CDI growth and population growth, economic activity intensity, population density, and improvement in the living environment showed a negative impact on CDI change. The results confirm the validity of estimating the multi-dimensional growth of regions using remote sensing data and provide a basis for differentiated spatial growth planning in urban, suburban, and rural areas. Full article

Urban sprawl poses a significant and escalating challenge in developing countries, including Iran, leading to substantial transformations in urban areas. Despite efforts to manage urban spatial development, uncontrolled urban sprawl exerts considerable pressure on resources, infrastructure, and the environment. This study aims to identify and quantify the drivers of urban sprawl and investigate their interrelationships within Iranian metropolises. To achieve this objective, the study employs a mixed-method approach, commencing with a review of the existing literature and expert surveys based on PESTEL analysis and the Delphi method. This stage identified and categorized 40 key drivers (sub-factors) into six main categories (factors): political, economic, social, technological, environmental, and legal. Subsequently, the DEMATEL-based Analytic Network Process (DANP) method is utilized to explore the internal interrelationships among factors and sub-factors and to determine their relative weights, offering deeper insights into their relationships and relative importance. The findings reveal a complex interplay of political, economic, social, technological, environmental, and legal factors driving urban sprawl in Iran. Key drivers include political fragmentation, economic competition, social preferences for suburban living, rural-to-urban migration, increasing housing demand, weak legal regulations, natural constraints, inadequate transportation infrastructure, and the impact of technological advancements. Based on these findings, the study recommends a holistic approach to sustainable urban development in Iran, emphasizing the need for stakeholder engagement, participatory decision making, legal reforms, and significant investments in public transportation infrastructure. Full article

This article investigates the performance of the Galileo Open Service Navigation Message Authentication (OSNMA) system in real-life environments prone to RF interference (RFI), jamming, and/or spoofing attacks. Considering the existing data that indicate a relatively high number of RFI- and spoofing-related incidents reported in Eastern Europe, this study details a data-collection campaign along various roads through urban, suburban, and rural settings, mostly in three border counties in East and South-East of Romania, and presents the results based on the data analysis. The key performance indicators are determined from the perspective of an end user relying only on Galileo OSNMA authenticated signals. The Galileo OSNMA signals were captured using one of the few commercially available GNSS receivers that can perform this OSNMA authentication algorithm incorporating the satellite signals. This work includes a presentation of the receiver’s operation and of the authentication results obtained during test runs that experienced an unusually high number of RFI-related incidents, followed by a detailed analysis of instances when such RFI impaired or fully prevented obtaining an authenticated position, velocity, and time (PVT) solution. The results indicate that Galileo OSNMA demonstrates significant robustness against interference in real-life RF-degraded environments, dealing with both accidental and intentional interference. Full article

The conversion of open space to residential development increasingly continues across the United States, impacting both humans and nature. Residential development requires public input to generate meaningful places and understand contextually relevant priorities. Most municipal policies do not guarantee the provision of open spaces when residential development occurs, missing opportunities for benefits to those communities and reducing both environmental and spatial justice. This study operated a seven-state verbal questionnaire to collect and analyze a small-sample population perceptions concerning open space conservation and green space preferences towards future residential development priorities. Statistical analytical results indicated patterns, trends, and relationships within data. Although 46% of United States residents living in rural, suburban, and urban community types believe the amount of open space required in new developments should be determined on a case-by-case basis, just under half believe that requiring at least 50% open space in new developments is appropriate. More than half of Americans in the states targeted, particularly Colorado and liberal-leaning respondents, believe a lack of coherent planning will prevent open space conservation and that open space planning and conservation should be a priority for city governments. Beyond the United States, this study provides research and insight into conservation strategies that foster healthier landscapes and living environments globally. Full article

Urban environments experience amplified thermal stress due to the climate change, leading to increased health risks during extreme temperature events. Existing numerical weather prediction systems often lack the spatial resolution required to capture this phenomenon. This study assesses the efficacy of a coupled modeling system, the numerical weather prediction AROME model and the land-surface model SURFace EXternalisée in a stand alone mode (SURFEX-SA), in forecasting air temperatures at high resolutions ($2.5$km to $100$m) across four Austrian cities (Vienna, Linz, Klagenfurt and Innsbruck). The system is updated with the, according to the author’s knowledge, most accurate land use and land cover input to evaluate the added value of incorporating detailed urban environmental representations. The analysis focuses on the years 2019, 2023, and 2024, examining both summer and winter seasons. SURFEX-SA demonstrates improved performance in specific scenarios, particularly during nighttime in rural and suburban areas during the warmer season. By comprehensively analyzing this prediction system with operational and citizen weather stations in a deterministic and probabilistic mode across several time periods and various skill scores, the findings of this study will enable readers to determine whether high-resolution forecasts are necessary in specific use cases. Full article

Environmental pollution with pesticides as a result of intensive agriculture harms the development of bee colonies. Bees are one of the most important pollinating insects on our planet. One of the ways to protect them is to relocate and build apiaries in populated areas. An important condition for the development of bee colonies is the rich species diversity of flowering plants and the size of the areas occupied by them. In this study, a methodology for detecting and distinguishing white flowering nectar source trees and counting bee colonies is developed and demonstrated, applicable in populated environments. It is based on UAV-obtained RGB imagery and two convolutional neural networks—a pixel-based one for identification of flowering areas and an object-based one for beehive identification, which achieved accuracies of 93.4% and 95.2%, respectively. Based on an experimental study near the village of Yuper (Bulgaria), the productive potential of black locust (Robinia pseudoacacia) areas in rural and suburban environments was determined. The obtained results showed that the identified blooming area corresponds to 3.654 m², out of 89.725 m² that were scanned with the drone, and the number of identified beehives was 149. The proposed methodology will facilitate beekeepers in choosing places for the placement of new apiaries and planning activities of an organizational nature. Full article