Land Mobile Research Articles

Neural Network SNR Prediction for Improved Spectral Efficiency in Land Mobile Satellite Networks

The use of satellites to cover remote areas is a promising approach for increasing communication availability and reliability. The satellite resources, however, can be quite costly, and developing ways to optimize their usage is of great interest. Optimizing spectral efficiency while keeping the transmission error rate above a certain threshold represents one of the crucial aspects of resource optimization. This paper provides a novel strategy for adaptive coding and modulation (ACM) employment in land mobile satellite networks. The proposed solution incorporates machine learning techniques to predict channel state information and subsequently increase the overall spectral efficiency of the network. The Digital Video Broadcasting Satellite Second Generation (DVB-S2X) satellite protocol is considered as the use case, and by using the developed channel simulator, this paper performs an evaluation of the proposed machine learning solutions for channels with various characteristics, with a total of 90 different observed channels. The results show that a convolutional neural network with a modified loss function consistently achieves an improvement (over 100% in some scenarios) of spectral efficiency compared to the state-of-the-art ACM implementation while keeping the transmission error rate under 0.01 for single channel evaluation. When observing two channels, an improvement of more than 300% compared to the outdated information spectral efficiency was obtained in multiple scenarios, showing the effectiveness of the proposed approach and allowing optimization of the handover strategy in satellite networks that allow user-centric handover executions.

Design and Implementation of a Land-Air Omnidirectional Mobile Robot

This paper proposes a new type of omnidirectional mobile robot for land and air, which has three motion modes, combines the motion characteristics of land motion and air flight, has the ability to climb walls, and can be actively deformed to adapt to the working conditions according to the current working environment. The robot incorporates an innovative “rotor blade–single row omnidirectional wheel” composite structure, which is mainly characterized by a single row of continuous switching wheels covering the outside of each rotor blade, and does not need to provide additional power when moving on the ground and walls, relying on the driving force generated by the rotor blades to drive the continuous switching wheels driven by the rotor blades. This structure can effectively combine the land movement mode, wall crawling mode, and air flight mode, which reduces the energy consumption of the robot without increasing the weight, and we design a deformation device that can realize the transformation of the three modes into each other. This paper mainly focuses on the design of the robot structure and the analysis of the movement method, and the land omnidirectional movement experiments, wall crawling experiments, and air flight experiments were, respectively, carried out, and the results show that the proposed land and air omnidirectional mobile robot has the ability to adapt to the movement of each scene, and improves the upper limit of the robot’s operation.

Decoding cargo bikes’ potential to be a sustainable last-mile delivery mode: an operations management perspective

ABSTRACT Cargo bikes are considered as a low-cost and flexible last-mile solution for the transport of goods. However, there are few studies that identify and contextualise the factors underpinning their sustainable operations and potential to effectively work as the last leg of a green, efficient, and societally beneficial supply chain. The authors addressed this gap by systematically collecting and thematically analysing 49 articles published between 2017 and 2023. The findings demonstrate that cargo bikes can utilise their potential as a sustainable last-mile delivery mode if: (a) their operations are optimised (from parking to routing and from traffic management to load capacity planning); (b) their social sustainability performance is enhanced (e.g. safety, security, fatigue of workforce); and (c) the cities hosting them invest in bike-friendly infrastructure, regulatory frameworks, land use approaches and mobility hubs. This paper offers cargo bike insights that can assist relevant stakeholders to enhance their efficiency and overall adoption.

Statistical channel modeling for low-elevation in LEO satellite communication

Channel modeling plays a crucial role in measuring wireless communication performance. This paper describes statistical channel modeling for a recorded signal from a ground station in an urban area in Tehran. This signal was recorded from the GRBALPHA satellite at 170–180° elevation and fixed azimuth. The three-state Markov channel modeling is used for this case. Markov models are often used for Land Mobile Satellite Channels (LMSC) because when the user is moving at different speeds between different environments, this causes, Variety in received power. By analyzing the communication channel in the lower elevations, the link budget can be designed with a suitable margin by considering the channel specification and its limitations. In addition to increasing communication time, reducing the bit error rate (BER), lowering costs, etc., this causes a more accurate channel analysis from the beginning to the end of the satellite passage.This work presents a statistical model for channel simulation using the Markov multi-state chain, estimating the Markov channel model between a fixed ground station and a Low Earth Orbit (LEO) Satellite at low elevations. The comparison of simulation data with recorded data demonstrates the proposed approach's effectiveness in modeling the channel.

Surface Temperature Distribution Through Vegetation Density and Building growth in Makassar City

The high temperature phenomenon is an event where the temperature in the city area is hotter than the surrounding area. Indonesia is located in a tropical climate, so several cities have the potential for temperatures to rise during the dry season. The city of Makassar is one of the cities with a high level of urbanization. With residents' enthusiasm for looking for work in the city, the land around the city has been converted into built-up land. Conditions like this make the existence of green open space uneven. This research aims is to determine the distribution of high-temperature phenomena through a spatial approach using remote sensing technology and geographic information systems. This research uses Landsat imagery for 2022 with the Land Surface Temperature (LST), Normalized Difference Vegetation Index (NDVI), and Normalized Difference Built-up Index (NDBI) methods. The results of the research explain that the large number of existing buildings has caused an increase in urban temperatures, from an initial temperature of 29.93 oC to 39.51 oC.The increase in temperature occurs throughout the year, with the hottest peak temperature reaching 37 oC on April 15, 2022. The condition of vegetation density decreased by 0.05, starting from 0.66 in 2012 to 0.61 in 2022; this is in line with the increase in building area to 15,368 ha in 2022. This condition makes Makassar City one of the hottest cities in Indonesia. With an increasingly high need for built-up land and high mobility, it has the potential to accelerate temperature changes, so it is necessary to provide green open space in densely built areas by creating public open spaces. open private.

A Study on the Spatial Growth and Housing in Mingora, Pakistan (Phases of Expansions and Appraisal on the Criteria of Sustainable Cities)

Mingora as a city that has grown exponentially through years and has faced many challenges both manmade and natural through the phases of its development. From administrative changes to conflict, floods, earth quake and climate change, while these challenges are global, the urban fabric of Mingora Swat is majorly affected. This research critically appraises Mingora city through the lens of criteria for sustainable cities based on Land Use, Housing, Mobility, Economic development, Health and Green systems to establish its current status and finds major issues in terms of housing, haphazard expansion and transportation means in the city resulting in a lowered quality of life. This study aims to shed light on the current status of Mingora city, provide insight and devise a starting point and direction for policy and decision makers, by providing a devised development plan for sustainable interventions that the city requires.

On sustainable land rent

IntroductionThis paper introduces the concept of Sustainable Land Rent (SLR), providing a comprehensive, multidimensional exploration anchored in the dynamics of its origin, separability, mobility, valuation, and the imperative for equitable distribution. SLR capitalizes on the economic mobility of land’s value to enhance community welfare and promote environmental sustainability. Advocating for the systematic institutionalization of SLR, the research tackles the complex challenge of distinguishing land value from improvements.MethodsEmploying traditional Price, Cost, and Income (PCI) methods as practiced in North America, the study addresses the technical challenge of inseparability by estimating and integrating the SLR value within each of these methods. The methodology clarifies the valuation process and establishes an objective framework for resource allocation and negotiation between public and private sectors.Results and discussionFurthermore, our findings highlight SLR’s vital role in advancing public revenue generation and underscore its function as an innovative catalyst for integrating sustainability into economic valuation models and practices in real estate development and urbanization.

Land Security and Mobility Frictions

Abstract Frictions that impede the mobility of workers across occupations and space are a prominent feature of developing countries. We disentangle the role of insecure property rights from other labor-mobility frictions for the reallocation of labor from agriculture to nonagriculture and from rural to urban areas. We combine rich household and individual-level panel data from China and an equilibrium quantitative framework featuring sorting of workers across locations and occupations. We explicitly model the farming household and the endogenous decisions of who operates the family farm and who potentially migrates, capturing an additional channel of selection in the household. We find that land insecurity has substantial negative effects on agricultural productivity and structural change, raising the share of rural households operating farms by over 40 percentage points and depressing agricultural productivity by more than 20%. Comparatively, these quantitative effects are as large as those from all residual labor-mobility frictions. We measure a sharp reduction in overall labor-mobility barriers over 2004–2018 in the Chinese economy, all accounted for by improved land security, consistent with reforms covering rural land in China during the period. JEL Codes: O11, O14, O4, E02, Q1.

The Inter-Relationships of Territorial Quality of Life with Residential Expansion and Densification: A Case Study of Regions in EU Member Countries

High-density urban development is promoted by both global and local policies in response to socio-economic and environmental challenges since it increases mobility of different land uses, decreases the need for traveling, encourages the use of more energy-efficient buildings and modes of transportation, and permits the sharing of scarce urban amenities. It is therefore argued that increased density and mixed-use development are expected to deliver positive outcomes in terms of contributing to three pillars (social, economic, and environmental domains) of sustainability in the subject themes. Territorial quality of life (TQL)—initially proposed by the ESPON Programme—is a composite indicator of the socio-economic and environmental well-being and life satisfaction of individuals living in an area. Understanding the role of urban density in TQL can provide an important input for urban planning debates addressing whether compact development can be promoted by referring to potential efficiencies in high-density, mixed land use and sustainable transport provisions. Alternatively, low-density suburban development is preferable due to its benefits of high per capita land use consumption (larger houses) for individual households given lower land prices. There is little empirical evidence on how TQL is shaped by high-density versus low-density urban forms. This paper investigates this topic through providing an approach to spatially map and examine the relationship between TQL, residential expansion, and densification processes in the so-called NUTS2 (nomenclature of terrestrial units for statistics) regions of European Union (EU) member countries. The relative importance of each TQL indicator was determined through the entropy weight method, where these indicators were aggregated through using the subject weights to obtain the overall TQL indicator. The spatial dynamics of TQL were examined and its relationship with residential expansion and densification processes was analysed to uncover whether the former or the latter process is positively associated with the TQL indicator within our study area. From our regression models, the residential expansion index is negatively related to the TQL indicator, implying that high levels of residential expansion can result in a reduction in overall quality of life in the regions if they are not supported by associated infrastructure and facility investments.

La Carrera de Campeche (1717-1818): demografia móvel, devoções vernáculas e estradas provincias

This article studies how the Carrera de Campeche, a series of fluvial and land traffic and mobility routes, connected the city port of Campeche and the gulf of Mexico with the Carrera de Guatemala, the commercial circuit that linked the audiencias/kingdoms of New Spain and Guatemala. For this, a review of the regional, economic historiography and anthropological studies was made; also archival documents and cartography collected in Mexico, Guatemala, the United States and Spain to support the hypothesis of the existence of the routes. As a result, it was possible to corroborate the existence of a dynamic demography and in continuous movement, fortified by regional devotions that strengthened the religious-cultural integration and that allowed to sustain the road projects of magistrates and elites in the Carrera de Campeche, at the end of the Spanish colonial period.

Techno-economy of lithic raw materials in Piedmont (north-western Italy): A first life-like scenario

Data about Palaeolithic peopling, settlement dynamics and techno-economy of the south-western margin of the Alpine region are sketchy. In this area, the lack of systematic research and the scarcity of lithic raw materials, spread the idea that Piedmont was not inhabited during Palaeolithic. In 2009, the re-starting of the excavations at the Ciota Ciara cave, gave rise to new questions and to the development of research projects at a regional scale.
 The Ciota Ciara cave is the only Middle Palaeolithic site object of multidisciplinary and systematic investigations. Its lithic assemblage, analysed through a techno-economic approach, allows to understand in detail the technological choices and the land mobility of the Neanderthal groups on a local and sub-regional scale. Other Middle Palaeolithic assemblages are known in the region and are all issued from surface collections. They come from the northern part of the region, from Vaude Canavesane, Trino, Baragge biellesi and Colline Novaresi. The technological study of these assemblages led to the identification of strong similarities in the technological choices of the Middle Palaeolithic human groups: they based their technology on the exploitation of vein quartz, a rock diffused all over the regional territory, from time to time accompanied by other local (spongolite, rhyolite, metamorphic rocks, jasper) and allochthonous (radiolarite and flint) lithic resources, with technological adaptation to their quality and mechanical properties both when it comes to predetermined methods (Levallois and discoid) and when expedient reduction sequences are used. Concerning Upper Palaeolithic, the only lithic assemblage issued from an archaeological excavation (and therefore with a clear stratigraphic context) is that from the Epigravettian site of Castelletto Ticino. Other lithic artefacts referable on a techno-typological basis to Upper Palaeolithic are from Trino and Colline Novaresi. As for Middle Palaeolithic, the techno-economic approach used in the analysis of these lithic assemblages, allow to have, for the first time, reliable data at a regional scale.
 In this work we present the data obtained after about ten years of research in Piedmont: they outline a scenario where, even in the limits of analysis mostly based on materials issued from surface collections, we can see both clear differences between the Middle and the Upper Palaeolithic technological behaviours and hypothesise the land mobility of the hunter-gatherers’ groups that inhabited the region.

Urban growth by fragments. Consolidation and land value in peripheral areas resulting from housing policy in Córdoba, Argentina

The study of the consolidation of built-up areas in the periphery of cities is interesting because it is linked to the differential forms of access to land, services, urban facilities, workplaces, and daily mobility for the inhabitants. The research identifies the locations of public housing in Córdoba city and the transformations that were produced in the physical morphology of the surroundings during a decade. Land uses, the level of building consolidation, and the dynamics of land prices in the surrounding areas lead us to reflect on the evolution of social housing areas as urban fragments built on the periphery. The objectives of the study are to recognize the effects of housing policy location in urban development and to discuss the sustainability of the urban-growth model. In the context of the increasing commodification of the city, this development pattern intensifies socio-territorial inequalities derived from the location of low-income families in scattered outlying areas.

Public safety network design for broadband wireless access

Public protection and disaster relief (PPDR) agencies rely on wireless communications to respond in the event of emergencies. Public safety networks (PSNs) provide the wireless network used by emergency services. PSN is used to support push-to-talk services with some data transmission by employing land mobile radios. However, PPDR agencies are increasingly relying on additional information such as videos that require higher bandwidths. Therefore, many countries are transitioning or integrating their public safety networks with advanced broadband wireless communication systems such as fourth-generation (4G) long-term evolution (LTE) and planning to evolve to fifth-generation (5G) new radio (NR) in the future. The paper investigates infrastructure sharing mechanisms and deployment strategies in the transition of PSNs to a 4G LTE network, including a roadmap for cost analysis. Additionally, the paper examines LTE-based PSN deployment scenarios in various countries and engages in a discussion of the advantages and disadvantages of different sharing mechanisms and coexistence schemes. Finally, the challenges within the Public Safety Broadband Network (PSBN) are addressed and potential future research directions in this domain are deliberated.

Climate adaptation in informal areas in hot arid climates

AbstractThis conceptual and exploratory research study investigates, systematically and holistically, climate‐adaptive spatial design interventions for high‐density informal urban areas in hot arid climates, which remain understudied despite their vulnerability to heat stress and the heat‐vulnerable groups populating them. Five streetscape design prototypes are proposed that include climate‐adaptive spatial interventions appraised qualitatively with consideration to relevant feasibility matters: land use planning, equity, affordability, mobility, and sense of place. The study shows that there is potential for climate‐adaptive interventions in informal urban areas in hot arid climates, but that these interventions also present challenges. Common climate‐adaptive design strategies can be used to address heat stress in these areas but, for example, increasing vegetation might be challenging due to water stress. As a conceptual study, the findings presented and the discussion raised on feasibility are targeted at opening avenues for future research, and at informing decision‐makers and spatial designers.

Enhancing urban public space through appropriate sustainable mobility policies. A multi-criteria analysis approach

Decision-making in the context of urban sustainability is a challenging problem for policy-makers, given its complex nature, demanding the compromise between different and, often, conflicting social, economic and environmental criteria. This multi-factor problem needs to be addressed in a holistic way, on the basis of an integrated transport and urban planning approach, through ad hoc planning for each different area. Land use and mobility policies are characterized by a high level of interaction, a fact that needs to be taken into account in urban and transport planning within the framework of sustainability. Effective land use policies may have a positive impact on sustainable mobility and vice versa: effective mobility policies may have a positive impact on sustainable land use in urban areas. Aiming at developing and testing via a case study a decision-support tool for policy-makers and decision-analysts to promote sustainable urban and transport planning, the application of two hybrid multi-criteria analysis models is proposed in this research work, in order to rank land use and transportation policies in the framework of urban sustainability, especially in terms of public space. The center of Thessaloniki (Greece), an urban area suffering from sustainable mobility and public space problems, is selected as a case study.

Planning a trip during Middle Palaeolithic. The mobile toolkit debate and some considerations about expedient vs curated technologies in the light of new data from the Ciota Ciara cave (NW Italy)

Since the term “personal gear” was introduced, the presence, in an archaeological lithic assemblage, of artefacts in allochthonous rocks has been considered as a source of information about land mobility and techno-economic organization. A technological and functional approach has been used to face the study of the lithic artefacts made in allochthonous raw materials from level 14 of the Ciota Ciara cave (north-western Italy). This level attests the phases of most intense frequentation of the cave, and it is the layer where allochthonous lithic raw materials are better represented. In a technological context described as markedly opportunistic, tools and unretouched flake, made in raw materials collected at a distance between 2 and 30 km, have been introduced in the site. The present work is aimed towards the understanding of the role of these artefacts within the technological organization of the Neanderthal groups that inhabited the cave. The results indicate that these “exotic” artefacts were part of a mobile toolkit and that they were multifunctional tools used for different activities (mainly butchering activities). We can hypothesize the transport within the site of finished products in the form of small, unretouched flakes and retouched tools, and, just sporadically, of small cores. The significative presence of Levallois radiolarite flakes in the Ciota Ciara toolkit is particularly interesting as the presence of this type of product in toolkits has already been reported by other scholars and for different European Middle Palaeolithic contexts. Moreover, the introduction in the site of unretouched flakes and of tools made in allochthonous and better-quality rocks could be interpreted as a planned behaviour, aimed at satisfying the need for more durable and efficient tools during the periods of staying at the Ciota Ciara cave.

DeepAir: Enabling Data-Driven Dynamic Spectrum Sharing via Scalable Forecasting

The rapid uptake of wireless technologies over the past decade has resulted in an increasing pressure on the limited radio spectrum resources. To improve the efficiency of current allocation policies, regulators in many jurisdictions are considering dynamic spectrum sharing. The success, however, of an optimized system hinges on the ability to sense, characterize, and forecast spectrum usage behaviour. Since traditional methods prove unable to scale to a wide range of channels, we propose DeepAir, a robust and scalable model that is capable of learning and predicting complex temporal and spectral dependencies in multivariate spectrum data. Specifically, we design a Sequence-to-Sequence model that employs an encoder-decoder architecture with two Deep Temporal Convolutional Networks. Using a test set consisting of approximately 900 channels in the Land Mobile Radio bands, we obtain a median RMSE and median MAE of 6.51 and 5.15, respectively. We then apply transfer learning to demonstrate the effectiveness of this model in forecasting patterns from any sensor, regardless of the band, sensitivity, and geographical location. Furthermore, the model exhibits no performance degradation up to three years after training for both short and long forecast horizons. Finally, we use DeepAir to quantify spectrum availability to enhance existing spectrum sharing capabilities.

Physical Layer Security in Interference Limited Land Mobile Satellite Communication Systems: Safeguarding Data Transmission

This paper focuses on evaluating the secrecy performance of a downlink land mobile satellite (LMS) system. The system faces the challenge of providing secure communication between a satellite and a legitimate user while an eavesdropper is present on the ground. Additionally, co-channel interference signals at the user's destination are considered. To address these issues, the study proposes a novel approach that utilizes Shadowed-Rician fading channels for satellite links and Nakagami-m fading for interfering terrestrial links. The main objective is to enhance the physical layer security of Interference-Limited Land Mobile Satellite Communication Systems. The approach incorporates advanced signal processing, beamforming, and artificial noise techniques to effectively manage interference. Encryption, authentication mechanisms, and intelligent power control strategies are implemented to protect transmitted data and optimize signal strength while reducing the risk of interception by potential eavesdroppers. Through comprehensive simulations, the proposed approach is thoroughly evaluated, demonstrating its effectiveness in achieving improved secrecy performance and increased resilience against security threats. The findings highlight the potential for its application in secure satellite communication systems operating in interference-constrained environments.

Challenges and Solutions for Service Continuity in Inter-PLMN Handover for Vehicular Applications

The reliability and availability of network connectivity, which significantly varies with mobility, is crucial in Connected, Cooperative and Automated Mobility (CCAM). Handover and roaming are the most challenging situations in terms of connectivity of cellular networks, which require switching across cells of the same cellular network or between Public Land Mobile Networks (PLMNs). This paper proposes a set of solutions for vehicular applications to mitigate the impact of mobility in service continuity, including a dual modem solution that reduces the interruption time when switching PLMNs, an adaptive bitrate mechanism for media streaming that increases reliability, a WebRTC server acting as a gateway in media streaming sessions between vehicles, and a MEC discovery and handover method. The proposed solutions have been evaluated executing an Extended Sensors application in several commercial and experimental 5G Non-Standalone (NSA) and Stand Alone (SA) setups with different Multi-access Edge Computing (MEC), edge-cloud and cloud infrastructures to host services. It can be concluded from the results obtained that 5G networks have not yet achieved the required performance for CCAM, and that practitioners need to implement solutions and workarounds, such as the ones proposed in this work, to mitigate the issues. As lessons learnt from the deployment and experimentation, this paper also overviews a detailed set of problems and the proposed solutions that CCAM industry and cellular network stakeholders need to consider.

Performance Evaluation of SSK Modulation Over Shadowed-Rician Land Mobile Satellite Links

We investigate the performance of satellite communication systems acquiring the space shift keying (SSK) modulation technique over shadowed-rician (SR) land mobile satellite (LMS) link. Specifically, we discuss the analytical performance of the considered system over independent and identically distributed SR fading channels in terms of symbol error rate (SER), diversity order, and average capacity. The SER of the considered set-up is derived by utilizing moment generating function (MGF) expression over the SR fading LMS communication links. The analytical diversity order of the scheme is derived by using SER expression. We consider the effect of elevation angles on the SER performance, diversity order, and channel capacity of the considered SSK-assisted satellite communication system. As observed from simulation and analytical results, the performance of the considered set-up can be raised by improving elevation angles. Further, a closed-form expression of the average capacity of the SSK assisted satellite communication system is also derived. It is shown through simulation and analysis that the fading conditions and elevation angle does not affect the diversity order of the system, but it adversely acts on the SER performance and average capacity of the system.