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Copyright of FME Transactions is the property of University of Belgrade, Faculty of Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of DYNA - Ingeniería e Industria is the property of Publicaciones Dyna SL and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to highlight the complexity in planning street sweeping in urban areas, an example is given based on the collection of the number of passages of sweeping vehicles during an observation period of one year. Data refer to a district of a European city whose street sweeping service was kept under monitoring with the aid of a software tracking sweeping vehicles and other operational parameters. The monitoring campaign pointed out the issues occurring during sweeping operations and the available margins of improvements. Two methodologies for optimization were proposed: a theoretical-analytical approach based on the attribution of weights to street characteristics and a hybrid approach, initially based on a previous experience in an urban area and later refined with the continuous analysis of data collected during sweeping operations. The present article shows that the second approach is the easier to adopt and allows for a flexible calibration of sweeping operations.

The article "Horses as Heroes in the Fight Against Diphtheria" discusses the crucial role horses played in producing diphtheria antitoxin in the late 19th and early 20th centuries. The serum derived from horses significantly reduced the mortality rate of diphtheria, leading to a decline in the disease's impact. The horses were treated with care and respect during the production process, highlighting their contribution to public health. [Extracted from the article]

One of the municipal waste streams is street cleaning waste, classified under code 20 03 03. They are not considered hazardous waste. Due to the lack of other management technology, they are sent to landfills. This waste, among other things, by its high chloride content especially after winter, can contribute to changes in the salinity of surface and groundwater and soil salinization, which consequently contributes to changes in the local environment and entire ecosystems. As it is deposited entirely in landfills, it also contributes to the salinity of leachate generated here. The Regulation of the Minister of Economy of July 16, 2015, on allowing waste to be deposited in landfills, the total organic carbon in waste deposited in non-hazardous and inert waste landfills must not exceed 5% of dry weight. The purpose of this article is to present a study of the quality of the waste on parameters like water content, organic and mineral fraction in the dry weight of the waste, and fractional separation. The water content of the waste ranged from 12–27%, while the mineral fraction in the dry weight was 91–94%. The smallest fraction below 0.05 mm accounted for 0d 1.8 to 4.5%. [ABSTRACT FROM AUTHOR]

In an effort to inform interventions targeting littering behaviour, we estimate how much a change in trash-bag colour increases trash can visibility in Paris. To that end, we applied standard Signal Detection techniques to test how much changing trash-bag colour affects subjects' trash can detection rates. In three pre-registered studies, we found that changing trash bag colour from grey to either red, green or blue considerably increases the perception of bins in British (tourist) and Parisian (resident) samples. We found that changing the bag colour from grey to blue increased visibility the most. [ABSTRACT FROM AUTHOR]

[Display omitted] • Street dust comprises large debris, a significant fraction of coarse particles, and minor fractions of PM 10 and PM 2.5 primarily containing crustal materials. • The composite filters comprising 3D-shaped fibrous demister filters are washable and regenerable for long-term operation. • Composite filtration system can be applicable for mitigating re-emitted particulate matter from street sweepers. • Theoretical prediction models for removal efficiency and pressure drop of the composite filter was developed. Street dust is an important fugitive emission source of particulate matter (PM), including total suspended particles (TSP), PM 10 , and PM 2.5. Street sweepers are normally used to remove street dust and garbage to keep the street clean, but they can contribute to secondary particle emissions due to a lack of effective particle control devices in the sweepers. This study aims to investigate the mass fraction of street dust to develop an effective filtration system to capture secondary particles. Silt (<94 µm) in the collected street dust contains mainly PM 10-94 with 94.14 % in the mass fraction. Based on the mass fraction data, a filtration system using composite filter media was designed, which consisted of 14 or 8 layers of flat or 3D-shaped fibrous demister filters with different porosities and fiber diameters for long-term operation and ease of regeneration using a water jet. The results showed that the 8-layer filter with an operating flow rate of 86 CMM (filtration velocity of 1.5 m/s) had desirable PM removal efficiency and long lifespan before regeneration. The initial pressure drop was only 43 Pa, while the initial removal efficiencies for TSP, PM 10 , and PM 2.5 were 89.0 %, 79.6 %, and 46.0 %, respectively. The efficiencies were increased with increasing dust loading, and finally, they reached > 96.7 % after 62.9 h of operation with a corresponding pressure drop of 996 Pa. After regeneration, the system's initial pressure drop and collection efficiency were fully recovered, demonstrating the system's sustainability and operational reliability. The developed theoretical models for the pressure drop and removal efficiency were in good agreement with the field data. To conclude, the developed composite filter can be used as a viable and economical device to avoid secondary particle emission from street sweepers and the theoretical model can be used for the design in various dust removal applications. [ABSTRACT FROM AUTHOR]

Water shortages are currently becoming a more global than local issue. This paper aims to demonstrate a complex, universal urban water reuse system, allowing for a reduction of freshwater withdrawal. Opportunities for improvement were analyzed in the categories of municipal services: power and heat production, greenery irrigation, landscaping, street and public transport fleet cleaning. Technical possibilities were coupled with current international legislative requirements. Two scenarios for universal, complex water reuse systems in the municipal area were evaluated, including all essential city services. Results of the case study show that ozonation and filtration of treated wastewater should be sufficient to obtain the desired water quality for urban purposes. Current legislation mainly addresses agricultural water reuse, so their requirements should be adjusted to assess the water quality needed for other applications. When water is used in public spaces, constant monitoring for the presence of pathogens should be maintained due to the risk of human exposure. A life cycle assessment was conducted to evaluate the environmental impacts associated with the topic of water transportation in urban areas, which is infrequently considered in such studies. Two scenarios including different means of transport were compared. It was shown that with constant daily operation, it is necessary to build an independent water network, since the environmental impact of water delivery by tank lorries increases substantially. [ABSTRACT FROM AUTHOR]

The aim of this paper is to shed light on the effects of the only privatisation that existed in the street cleaning service in Madrid. Framed within the international processes of privatisation since the 1970s and through a search in historical archives, it analyses the political-administrative and social factors that influenced this privatisation and its consequences on labour relations in the sector. Finally, the hypothesis of the planning of the privatisation of the service, the existence of differences with the political parties in the municipal government of Madrid and the effects of privatisation on the dualisation of working conditions affecting the further development of the service in the different districts of Madrid are tested. JEL Code: H75, I18, N9. [ABSTRACT FROM AUTHOR]

The aim of this paper is to shed light on the effects of the only privatisation that existed in the street cleaning service in Madrid. Framed within the international processes of privatisation since the 1970s and through a search in historical archives, it analyses the political-administrative and social factors that influenced this privatisation and its consequences on labour relations in the sector. Finally, the hypothesis of the planning of the privatisation of the service, the existence of differences with the political parties in the municipal government of Madrid and the effects of privatisation on the dualisation of working conditions affecting the further development of the service in the different districts of Madrid are tested.JEL Code: H75, I18, N9.

Road dust, containing tire-road wear particles, atmospheric dust, or construction-related particles, contaminates road environments and poses a health hazard when inhaled by humans. To further explore the particle size and composition of road deposit dust, this study collects these particles in Xi'an, considering various road grades, materials, service conditions, sections, and locations. The collected particles undergo electron microscopy, laser particle size, thermal, mass spectrometry, infrared spectroscopy, and inductively coupled plasma analyses. Qualitative and quantitative analysis of the particles has been conducted, leading to the following conclusions: Asphalt & tire contribute 8.5% of the road deposit dust, while wear from calcium carbonate accounts for approximately 30%. The average particle size on urban roads (392 μm) is 1.25 times that of rural roads (312 μm). The smaller particles on rural roads are more easily resuspended and inhaled, posing health risks and requiring more attention. Brake zones, which often have 1.4 times the metal content compared to mid-sections, including potentially carcinogenic chromium (Cr), should receive focused watering and adsorption due to brake zone where is also at intersections and pedestrian crossing. New roads, which generate 3-6 times more organic matter than old roads, requires continuous cleaning after opening to traffic. Surface-blocked asphalt concrete (AC) pavements, as their lack of pores can lead to easy re-suspension of deposited particles due to tire-road interaction should also be attention. This study aims to contribute to the field of traffic-related dust pollution cleaning strategies and non-exhaust emissions mitigation measures in the future. [ABSTRACT FROM AUTHOR]

Waste from street cleaning is usually of a fine fraction below 10 mm and varies greatly in both quantity and composition. It may be composed of chlorides, especially for that resulting during winter due to the use of street de-icing agents. Chlorides can cause the salinization of surface water and groundwater, and the salinization of soils, which in turn lead to the deterioration of water purity and a decrease in biodiversity of aquatic organisms, changes in microbiological structure, and increases in toxicity of metals. Therefore, it is very important to determine the level of salinity in stored waste and its impact on the environment. The present study was conducted in a city of about 55,000 inhabitants. The highest chloride concentrations were observed after winter in waste from street and sidewalk cleaning around the sewer gullies, amounting to 1468 mg/dm3. The lowest chloride concentration in this waste occurred in summer and amounted to 35 mg/dm3. The multi-criteria analysis indicated that the most beneficial form of street cleaning and, thus, of reductions in chloride concentration in the waste from street cleaning, would be sweeping and daily washing. The objective of this research was to determine the amount of chlorides in sweepings on an annual basis in order to determine the potential risks associated with their impact on select aspects of the environment and to evaluate the frequency of necessary cleaning for city streets, considering the effects. The methodology used was a multi-criteria evaluation, which as a decision analysis, allowed us to determine the frequency of cleaning and washing of streets, in such a way that an ecological effect is achieved with simultaneous economic efficiency. [ABSTRACT FROM AUTHOR]

Object detection is a central task in computer vision, with applications ranging across the process of smart city construction, city managers always spend a lot of energy and money cleaning street garbage due to the random appearances of street garbage, As deep network solutions become deeper and more complex, they are often limited by the amount of training data available. With this in mind, to spur advances in analyzing and understanding images, Open CV or Google AI has publicly released the Open Images dataset. Open Images follows the tradition of PASCAL VOC, Image Net and COCO, now at an unprecedented scale. In this project we to implement the Consequently, visual street cleanliness assessment is particularly important. However, existing assessment approaches have some clear disadvantages, such as the collection of street garbage information is not automated, and street cleanliness information is not real-time best performing algorithm for automatically detecting objects. Finally, the results are incorporated into the street cleanliness calculation framework to ultimately visualize street cleanliness levels, which provides convenience for city managers to arrange clean-up personnel effectively. [ABSTRACT FROM AUTHOR]

At the beginning of the COVID-19 pandemic the government of Spain decreed the State of Alarm to confine the entire population at their homes, except for essential services. Therefore, the central objective of this study is to evaluate the implication of this situation for the environmental noise existing in the city of Huelva (Spain). This study demonstrates that during the state of alarm an average daily reduction of 3.4 dBA was noted, and in the central moments of the day these reductions reached up to 4.4 dBA, while from 10:00 to 12:00 pm the reduction was around 6.5 dBA. Nevertheless, there were two moments of day: 3:00 am (garbage collection, street cleaning and container disinfection), and 8:00 pm (daily applause for health professionals), when the noise during the pandemic was higher than before it. It is further shown that globally, the loudest events only decreased by about 3 dBA, while the global background noise decreased by 10 dBA during the alarm state. Regarding road traffic noise, it is verified that in addition to being reduced by about 4 dBA, traffic represents 6.7% of noisy events during the alarm state, while before it represented 13%. [ABSTRACT FROM AUTHOR]

According to the data of the Central Statistical Office for 2017, the average amount of municipal waste generated per capita is 486 kg. Poland ranks last but one in terms of the amount of municipal waste generated. About 56% of municipal waste is processed, but still about 40% is landfilled. They may contain chlorides, especially those from the winter period, resulting from the use of deicing agents. Chlorides cause salinity of surface and ground waters and soil salinity, which in turn leads to deterioration of water purity and a decrease in biodiversity of aquatic organisms, changes in the microbiological structure and increased toxicity of metals. Chlorides also damage road surfaces and bridges, corrosion of plumbing pipes. Once the chlorine-containing sweepers are deposited in a landfill, this waste may contribute to an increase in chemical aggressiveness, which is important in the design of anti-filtration barriers, and in the rehabilitation of contaminated land and soil. The level of water and soil salinity has a significant impact on the critical infrastructure, especially in terms of water supply – the risk of corrosion of pipes and their decline in species biodiversity. An important role in the critical infrastructure is played by the storage of dust muds – the risk of failure of security measures in storage yards. Therefore, it is very important to determine the salinity level in this stored waste. The salinity level of street sweeping waste from different street locations is not commonly studied. Therefore, such a study was conducted for a midsized city. The study shows that the highest chloride concentrations in street and sidewalk sweeping waste are found around manholes and the lowest concentrations are found on sidewalks. The aim of the research is to determine the amount of chlorides in sweepings in the annual cycle to determine the potential risk associated with their impact on selected aspects of the environment. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to propose a decision support system (DSS) for maintenance management of a service system, namely, a street cleaning service vehicle. Referring to the information flow management, the blockchain technology is integrated in the proposed DSS to assure data transparency and security. Design/methodology/approach: The DSS is designed to efficiently handle the data acquired by the network of sensors installed on selected system components and to support the maintenance management. The DSS supports the decision makers to select a subset of indicators (KPIs) by means of the DEcision-MAaking Trial and Evaluation Laboratory method and to monitor the efficiency of performed preventive maintenance actions by using the mathematical model. Findings: The proposed maintenance model allows real-time decisions on interventions on each component based on the number of alerts given by sensors and taking into account the annual cost budget constraint. Research limitations/implications: The present paper aims to highlight the implications of the blockchain technology in the maintenance field, in particular to manage maintenance actions' data related to service systems. Practical implications: The proposed approach represents a support in planning, executing and monitoring interventions by assuring the security of the managed data through a blockchain database. The implications regard the monitoring of the efficiency of preventive maintenance actions on the analysed components. Originality/value: A combined approach based on a multi-criteria decision method and a novel mathematical programming model is herein proposed to provide a DSS supporting the management of predictive maintenance policy. [ABSTRACT FROM AUTHOR]

The hygienic quality of urban surfaces can be impaired by multiple sources of microbiological contaminants. These surfaces can trigger the development of multiple bacterial taxa and favor their spread during rain events through the circulation of runoff waters. These runoff waters are commonly directed toward sewer networks, stormwater infiltration systems or detention tanks prior a release into natural water ways. With water scarcity becoming a major worldwide issue, these runoffs are representing an alternative supply for some usage like street cleaning and plant watering. Microbiological hazards associated with these urban runoffs, and surveillance guidelines must be defined to favor these uses. Runoff microbiological quality from a recently implemented city center rainwater harvesting zone was evaluated through classical fecal indicator bacteria (FIB) assays, quantitative PCR and DNA meta-barcoding analyses. The incidence of socio-urbanistic patterns on the organization of these urban microbiomes were investigated. FIB and DNA from Human-specific Bacteroidales and pathogens such as Staphylococcus aureus were detected from most runoffs and showed broad distribution patterns. 16S rRNA DNA meta-barcoding profilings further identified core recurrent taxa of health concerns like Acinetobacter , Mycobacterium , Aeromonas and Pseudomonas , and divided these communities according to two main groups of socio-urbanistic patterns. One of these was highly impacted by heavy traffic, and showed recurrent correlation networks involving bacterial hydrocarbon degraders harboring significant virulence properties. The tpm -based meta-barcoding approach identified some of these taxa at the species level for more than 30 genera. Among these, recurrent pathogens were recorded such as P. aeruginosa, P. paraeruginosa, and Aeromonas caviae. P. aeruginosa and A. caviae tpm reads were found evenly distributed over the study site but those of P. paraeruginosa were higher among sub-catchments impacted by heavy traffic. Health risks associated with these runoff P. paraeruginosa emerging pathogens were high and associated with strong cytotoxicity on A549 lung cells. Recurrent detections of pathogens in runoff waters highlight the need of a microbiological surveillance prior allowing their use. Good microbiological quality can be obtained for certain typologies of sub-catchments with good hygienic practices but not all. A reorganization of Human mobility and behaviors would likely trigger changes in these bacterial diversity patterns and reduce the occurrences of the most hazardous groups. • Socio-urbanistic differentiation of rainwater harvesting urban sub-catchments. • Recurrent high counts of fecal bacteria and pathogens among downtown runoff waters. • Use of DNA meta-barcoding approaches for inferring urban surface hygienic status. • 16S rRNA and tpm metabarcoding profiles of urban runoff match traffic intensity. • Highly cytotoxic Pseudomonas paraeruginosa bacterial cells found over city surfaces. [ABSTRACT FROM AUTHOR]

• Local governments (LGs) with greater citizen participation are more efficient in waste collection. • More transparent LGs are less efficient in the provision of the street cleaning. • Public management of the waste collection and street cleaning is more efficient. • In waste collection, higher population density translates into improved efficiency. • Tourist municipalities are less efficient in providing waste collection services. Currently, in all developed countries there is great interest in improving democratic practices in local governments, as the administration closest to citizens. However, the possible influence of these actions on the management of public services and municipal finances have been side-lined, despite the great interest in evaluating the performance of local governments under budgetary constraints. Our research aims to fill this knowledge gap by studying the impact of key aspects of local governance (transparency and citizen participation), together with other environmental variables, on the efficiency of two municipal public services of both qualitative and quantitative importance: waste collection and street cleaning. The results show that the type of management, population density, the tourist activity of the municipality and the strength of local government are determinants that explain the efficiency of the public services examined in this research, while transparency and citizen participation have little impact. [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Pesquisa em Turismo is the property of Associacao Nacional de Pesquisa e Pos-Graduacao em Turismo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Transport of contaminants from roadways to the environment is well known, although studies of technologies for preventing and managing this appear infrequently in the literature. This paper reviews technologies studied for radiological contaminants. In addition to nuclear facility decommissioning, nuclear power plant accidents at Chernobyl (Former Soviet Union), Fukushima (Japan) and elsewhere have provided real world situations to both develop and test technologies to remediate radiological contamination and to return roadways, along with adjacent vegetation and soil, to prior use. From publications arising from these efforts, technologies were reviewed for radioactive material with two distinct properties (water-soluble and insoluble radioactive contaminants). The reported characteristics and capabilities of technologies are summarized in this review. This review also presents logistical considerations of implementation of the technologies, including waste management which can be an extreme impediment to rapid remediation if generated quantities of hazardous waste exceed local handling capacity. The summarized literature review suggests future avenues of work, chiefly for insoluble particulates, focused on technologies which may be mechanistically applicable to their remediation. While the underlying chemical and physical mechanisms that contribute to transport differ among contaminants, the studies reviewed here might also be applicable to non-radioactive contaminants, because the presence of radioactivity is largely independent of the underlying mechanisms.

During the process of smart city construction, city managers always spend a lot of energy and money for cleaning street garbage due to the random appearances of street garbage. Consequently, visual street cleanliness assessment is particularly important. However, the existing assessment approaches have some clear disadvantages, such as the collection of street garbage information is not automated and street cleanliness information is not real-time. To address these disadvantages, this paper proposes a novel urban street cleanliness assessment approach using mobile edge computing and deep learning. First, the high-resolution cameras installed on vehicles collect the street images. Mobile edge servers are used to store and extract street image information temporarily. Second, these processed street data is transmitted to the cloud data center for analysis through city networks. At the same time, Faster Region-Convolutional Neural Network (Faster R-CNN) is used to identify the street garbage categories and count the number of garbage. Finally, the results are incorporated into the street cleanliness calculation framework to ultimately visualize the street cleanliness levels, which provides convenience for city managers to arrange clean-up personnel effectively. The overall approach is illustrated and visualized using the street images of Jiangning District in Nanjing, China. The practical application shows the feasibility and usability of the approach.