LTE and 5G NR – Coexistence and Collaboration

Exposure of acid aerosol for schoolchildren in metropolitan Taipei

In this study, the authors evaluated exposure to airborne polycyclic aromatic hydrocarbons (PAHs) in workers exposed to exhaust gas from cars, and they assessed the efficiency of urinary 1-hydroxypyrene as an indicator of exposure to pyrene and PAHs. The authors selected 2 groups of police who worked in 2 areas in the city of Florence: 1 group was highly exposed to high-density traffic emissions during the winter and summer of 1997, and the 2nd group experienced low exposure to traffic emissions during the same period. Ambient monitoring was achieved with personal sampling of airborne PAHs during each workshift. Eight hydrocarbons were used as indicators of pollution caused by PAHs (e.g., pyrene, benzo[a]pyrene, benzo[a]anthracene, dibenzo[a,h]anthracene). Biological monitoring was performed through dosing of 1-hydroxypyrene (pyrene metabolite) in urine samples taken at the end of each workshift. The ambient monitoring revealed that PAH concentrations were influenced by both season of sampling and varying intensities of traffic in the different areas. The median concentration of benzo[a]pyrene in winter was twice as high in the high-density traffic area as in the low-density traffic area (i.e., 4.1 ng/m3 versus 1.8 ng/m3). In summer, the high-density traffic area experienced benzo[a]pyrene concentrations that were 6 times higher than in the low-density traffic area (i.e., 1.2 ng/m3 versus 0.2 ng/m3). Benzo[a]pyrene was also correlated highly (r(s) = .92, p < .0001) with the mixture of total PAHs analyzed, thus confirming its function as a good indicator of exposure to PAHs in an urban environment. Levels of urinary 1-hydroxypyrene appeared to be generally influenced by the intensity of traffic, especially during the winter (i.e., median value in winter was 199.2 ng/gm creatinine in the high-density traffic area and 120.5 ng/gm creatinine in the low-density traffic area). An analysis of the general data revealed that 1-hydroxypyrene was, to some degree, related to pyrene, benzo[a]pyrene, and airborne total PAHs, whereas analysis of separate data for the area and the season revealed an emergence of a closer correlation during the winter in the high-traffic area. Therefore, 1 -hydroxypyrene can be considered a good biological indicator of exposure to airborne PAHs in the urban environment, especially in winter and in high-density traffic areas.

Petroleum hydrocarbon pollution of urban topsoil in Ibadan City, Nigeria

The digital transmission amongst vehicles and roadway equipment is necessary for the realization of smart transportation systems. Vehicular ad-hoc network (VANet) is an ascension field of engineering that presents brilliant transport applications, road safety, comfort and luxury to drivers. VANet protocols face many challenges because of the changing nature of vehicular ad-hoc network. VANet routing protocols perform a vital role in terms of the performance efficiency because they decide the mode of sending and receiving packets between mobile vehicular nodes. Finding suitable and efficient routing protocol is very important for the efficient implementation of VANet. The foremost objective of this research is to suggest the relevant and efficient VANet routing protocols in a high traffic density area. This research work presents a practical evaluation of the VANet topology’s features with respect to time for the high traffic situations. This evaluation incorporates the actual creation of roadway layout. An accurate traffic flow is produced by extracting run-time facts and figures from PeMS (Freeway Performance Measurement System) database and assigning this extracted information into a microscopic mobility model. To achieve our goal, we consider three routing protocols i.e., AOMDV, AODV and DSDV. The simulation results prove that the performance of AOMDV is greater in comparison to DSDV and AODV protocols in high traffic density areas. The AOMDV protocol improves overall network performance by achieving maximum throughput and minimum end to end delay.

A search for cheap and efficient method to monitor atmospheric particulates in city centres has raised new interest to measure foliar element concentrations after the role of particulate pollution for respiratory illnesses was discovered. Leaf samples of Golden dewdrop (Duranta repens L.) collected in Palermo (South of Italy) between 1998 and 2000 were analysed to study the possible use of this shrub as a passive biomonitor for atmospheric pollution in urban areas. Concentrations of Ba, Cd, Cu, Fe, Mg, Mn, Pb and Zn were determined from leaf samples collected from six sampling sites representing either (a) areas of high traffic density or (b) areas not directly affected by the city traffic (e.g. gardens). Most of the elements showed a significant temporal variation but no consistent trends could be seen, i.e. the highest (or lowest) values were not detected consistently at some particular time of the year. Furthermore temporal changes were of same magnitude in polluted versus less polluted areas; no statistically significant interaction between pollution level and collection period was detected. Pollution level (traffic density) was the primary factor to explain spatial variation only in the case of foliar Mg concentrations. On the other hand, variation in foliar concentrations between sampling sites (irrespective of the pollution level) was large. Our results suggest that particulate deposition needs to be quite high before spatial segregation can be done on the basis of foliar element concentrations.

An efficient identity-based signature scheme without bilinear pairing for vehicle-to-vehicle communication in VANETs

BackgroundTraffic policemen are identified to be at a higher risk of exposure to air pollution and its contaminants such as lead. A study done prior to the introduction of unleaded petroleum in Sri Lanka revealed a mean blood lead level of 53.07 μg/dL, which was well above the Center for Disease Control defined acceptable safe levels. This study aimed to determine whether unleading of fuel has made an impact on the blood lead levels of traffic police working in an urban area with high traffic density.MethodA cross-sectional survey of 168 traffic police personnel working within Colombo city limits of Sri Lanka, a high traffic density area, was conducted. Blood lead levels of participants were measured using nitric acid, perchloric acid ashing method and atomic absorption spectrophotometry. An interviewer administered questionnaire was used for a targeted history and examination.Results and discussionMean age of the sample population was 37 years. Thirty eight percent had detectable levels of lead in blood and 24.4% of the study sample had blood lead levels above Centre for disease control defined safe limits. Sample mean was 4.82 μg/dL (95% CI 3.58-6.04), and this is a 91% overall reduction when compared to data prior to unleading. Neither symptoms nor signs of classic lead toxicity showed significant correlation with toxic lead levels.ConclusionLead poisoning though still present in the high risk traffic warden population shows a considerable reduction following unleading. The need to have a low threshold to suspect lead poisoning is highlighted by the non-specific nature of the symptoms and signs of lead poisoning and its lack of association even in those found to have elevated lead levels. Further studies are required to elucidate a cause for the prevalence of lead poisoning despite cessation of using lead as an additive in petroleum.

Network designers expect a highly mobile, highly responsive, and quickly deployable network structure to enable communication in emergency situations. For this reason, a major research goal for emerging mobile network (mobile sensor network, mobile ad hoc network, etc.)is to achieve good coverage and robust communication performance by coordinated management of base stations or nodes. In this paper, we extend current methods to balancing cell load by taking base station mobility into account.We propose a novel distributed base station mobility strategy (DMS). We focus on a recently attractive network model where localized communication is supported by using mobile base stations (MBSs) placed on moving vehicles. In order to minimize the blocking rate in high traffic density area, the proposed strategy will lead the MBSs to suitable locations and re-share the whole traffic load. We demonstrate the convergence of this distributed mobility strategy by both theoretical analysis and numerical evaluations of realistic networks. The strategy enables each MBS to select destination efficiently and locally with limited information exchange. Compared with the traditional load balancing method based on transmit power control, the proposed algorithm has obvious advantages in reducing the dropped calls, especially with extremely uneven load distribution.

Nerium oleander L. (Oleander) leaves grown in Palermo city (Sicily, Italy) were collected from six sampling sites representing either areas of high traffic and urbanisation density or areas far away from traffic (e.g. city gardens). Concentration of Al, Ba, Cr, Cu, Fe, Pb, Mg, Mn, and Zn were determined in leaf samples during two years. Multivariate analysis classified the sampling sites in four groups based on the metal content in vegetal leaves in agreement with traffic and human activity site. Many elements studied (Al, Ba, Fe, Mn Mg) arise from the soil composition and others such as Cr, Cu, Pb and Zn as pollutant of the soil. On the other hand, about 30% of Al, Fe Cr, Cu and Pb originate from aerial deposition on leaves. Although the results presented should be handled with caution N. oleander can be considered as a means of assessing dust contamination in the urban environment.

Vessel traffic service systems (VTS systems) have been established, throughout the world, in areas of high traffic density. These systems, operating with such tools as VHF radiotelephony, land-based radar installations and ship's data processing, gather information to respond to collision and grounding danger, to organize traffic flow and assist allied activities. It is expected that VTS systems should effectively reduce the number of collisions in the VTS area. But efforts for collision avoidance can only be successful if the VTS operator in front of the shoreside radar screen is precisely instructed as to which measurements he has to make to identify a risk-of-collision situation. Uncertainties about the direction in which ships must take evasive action arise in VTS areas, where ships are free to engage in encounters.

&amp;lt;p&amp;gt;Urban Gardening has become increasingly popular globally in the past two decades as urbanites begin to recognise the benefits of growing their own food and the sense of community these gardening activities engender. These activities grow as citizens reclaim derelict land and are increasingly using roof top gardens and novel containers, providing much needed green oases in the city, concepts which are particularly popular with the &amp;amp;#8220;share&amp;amp;#8221; generation. However, many such sites are in areas of high traffic density, on brown field sites or on sites overlying landfill, as a result of their urban location. The proximity to such sites may lead to worries about the food safety and reduction of the adoption of such healthy urban gardening practices. One of the main concerns is the transfer of urban pollutants into the consumer&amp;amp;#8217;s food chain. Trace metals are one of the contaminants frequently found in urban crops and soils. Perceived concerns about the effects of these heavy metal contaminants on human health often outweigh the true risk; part of the problem is the lack of data in the urban production context. Moreover, collection of city-wide data on the health of the soil is often difficult and expensive to collect. In this project we intend to attempt to overcome these issues by recruiting citizens to conduct simple common collaborative experiments in their urban gardens, from these data we will create a city map of soil health status and providing information on potential risk of heavy metal contaminants and ways in which to mitigate those risks in an Urban Gardening context. We chose a citizen science approach in this project, not only as it will allow us to gather a wealth of data but also it will empower us to jointly generate useful information for the greater public good which can contribute towards creating green sustainable cities.&amp;lt;/p&amp;gt;&amp;lt;p&amp;gt;This project will place the citizen at the heart of the experimental process in contrast to more traditional observational data collection. Using an experimental approach really exposes the citizens to the scientific process and enables them to gain tacit knowledge of how scientists overcome variance, bias and arrives at scientifically sound evidence based conclusions. As a result, citizen science can provide reassurance to the public about the rigour and process of scientific enquiry. In doing so it can inspire confidence and understanding of the nuances of political bias; putting contextual knowledge together, in learning by doing.&amp;lt;/p&amp;gt;

The exponential growth in mobile data traffic, coupled with finite radio frequency resources, has intensified the challenges associated with efficient radio access network (RAN) planning and optimization in spectrum-constrained environments. As operators strive to meet increasing demands for high-speed connectivity and low-latency services, there is an urgent need for innovative strategies that can maximize spectral efficiency while ensuring quality of service (QoS) and user experience. This paper proposes a conceptual model for radio access planning and optimization specifically tailored to spectrum-limited settings, with a focus on dynamic resource allocation, interference management, and adaptive network configurations. The proposed model integrates multi-layered radio planning techniques, including spectrum reuse, frequency refarming, and heterogeneous network deployment, supported by real-time data analytics and artificial intelligence. The model introduces a feedback-driven architecture that continuously monitors network performance metrics—such as signal-to-interference-plus-noise ratio (SINR), throughput, and user mobility patterns—to guide adaptive reconfiguration of RAN parameters. Furthermore, it incorporates a spectrum-aware decision engine that enables efficient traffic offloading and load balancing across macro, micro, and small cells. To ensure robustness, the model accounts for regulatory constraints, spectrum licensing scenarios (licensed, unlicensed, and shared bands), and co-existence with legacy technologies. Emphasis is placed on the strategic placement of base stations, beamforming techniques, and interference coordination schemes such as enhanced Inter-Cell Interference Coordination (eICIC) and Coordinated Multipoint (CoMP). The framework also facilitates spectrum aggregation, dynamic carrier selection, and energy-efficient operations to enhance capacity without additional spectrum acquisition. This conceptual model serves as a valuable tool for mobile network operators, planners, and policymakers aiming to optimize network coverage and capacity under spectrum scarcity. It provides a scalable and technology-neutral blueprint applicable to 4G LTE, 5G NR, and emerging radio access technologies. Future work will focus on validating the model through simulations and real-world testbeds to refine its components and quantify its performance gains in diverse deployment scenarios.

The development and establishment of mobile communication technologies has necessitated assessments of possible risks to human health from exposures to radio-frequency electromagnetic fields (RF EMF). A number of expert committees have concluded that there is no evidence for such risks as long as exposures are at or below levels that do not allow tissue heating. These assessments have been based primarily on studies investigating frequencies up to 6 GHz including frequencies similar to those used by two of three major bands of fifth generation (more accurately 5G New Radio or 5G NR) of mobile communication. Bioeffects studies in so-called high-band at 25–39 GHz are particularly sparse. Future assessments relevant for these frequencies will need to rely on still unperformed studies. Due to few available studies at 5G NR “high band” frequencies, and questions raised by some existing studies, a recent review recommended a wide range of RF biostudies be done at 5G NR “high band” frequencies. It is of importance that such studies be done using the best possible science. Here we suggest factors to consider when performing future studies in this area. The present focus is on laboratory studies to clarify biological effects of radiofrequency (RF) energy at 5G “high band” frequencies and, more generally at millimeter wave (mm-wave) frequencies (30-300 GHz) which will be increasingly used by communications technologies in the future. Similar comments would apply to epidemiology and exposure assessment studies, but those are not the focus of the present Perspective.

Residential exposure to traffic in California and childhood cancer.

Santacruz airport constitutes a high traffic density area, with a- substantial number of jet aircraft movements. Aviation hazards at this airport get particularly accentuated during the monsoon season on account of the occurrence of very low clouds, strong gusty winds and poor visibility conditions in mist or haze, or showers. There are a- few important hill features a-round the airport, not far from the landing area.&#x0D; &#x0D; The airport is equipped with standard radio navigational aids, namely, very high frequency omnidirectional range (VOR), Instrument Landing System (ILS), the Aerodrome Surveillance Radar (ASR). A precision approach radar (PAR) will become operational at this airport shortly. On the ILS the glide path angle has recently been reduced from 4 degrees to 3.3 degrees above the horizon, necessitating the approach of the aircraft generally at a lower altitude, the altitude above the middle marker being of the order of 561 ft only. The distance of the middle marker from ARP is 2972 m (1.6 n.m.). Fig. 1 is the instrument approach chart for the Bombay airport.&#x0D; &#x0D; The aviation hazards that may be encountered by the jet aircraft especially in the monsoon season, on the phase of the final approach, have been discussed in this note with reference to climatological statistics and the synoptic climatology of this airport. It is hoped that the result arrived at will be of some practical value to pilots operating jet aircraft and to air traffic controllers.