scholarly journals Assessment of vertically-resolved PM<sub>10</sub> from mobile lidar observations

2009 ◽  
Vol 9 (21) ◽  
pp. 8617-8638 ◽  
Author(s):  
J.-C. Raut ◽  
P. Chazette
Keyword(s):  
Cross Sections ◽  
Urban Areas ◽  
Spatiotemporal Variability ◽  
Paris Area ◽  
Surface Measurements ◽  
Surface Network ◽  
Set Up ◽  
Outlying Regions ◽  
Lidar Observations ◽  
Mass Concentrations

Abstract. We investigate in this study the vertical PM10 distributions from mobile measurements carried out from locations along the Paris Peripherique (highly trafficked beltway around Paris), examine distinctions in terms of aerosol concentrations between the outlying regions of Paris and the inner city and eventually discuss the influence of aerosol sources, meteorology, and dynamics on the retrieved PM10 distributions. To achieve these purposes, we combine in situ surface measurements with active remote sensing observations obtained from a great number of research programs in Paris area since 1999. Two approaches, devoted to the conversion of vertical profiles of lidar-derived extinction coefficients into PM10, have been set up. A very good agreement is found between the theoretical and empirical methods with a discrepancy of 3%. Hence, specific extinction cross-sections at 355 nm are provided with a reasonable relative uncertainty lower than 12% for urban (4.5 m2 g−1) and periurban (5.9 m2 g−1) aersols, lower than 26% for rural (7.1 m2 g−1) aerosols, biomass burning (2.6 m2 g−1) and dust (1.1 m2 g−1) aerosols The high spatial and temporal resolutions of the mobile lidar (respectively 1.5 m and 1 min) enable to follow the spatiotemporal variability of various layers trapping aerosols in the troposphere. Appropriate specific extinction cross-sections are applied in each layer detected in the vertical heterogeneities from the lidar profiles. The standard deviation (rms) between lidar-derived PM10 at 200 m above ground and surface network stations measurements was ~14μg m−3. This difference is particularly ascribed to a decorrelation of mass concentrations in the first meters of the boundary layer, as highlighted through multiangular lidar observations. Lidar signals can be used to follow mass concentrations with an uncertainty lower than 25% above urban areas and provide useful information on PM10 peak forecasting that affect air quality.

scholarly journals Assessment of vertically-resolved PM<sub>10</sub> from mobile lidar observations

2009 ◽  
Vol 9 (3) ◽  
pp. 13475-13521 ◽  
Author(s):  
J.-C. Raut ◽  
P. Chazette
Keyword(s):  
Cross Sections ◽  
Spatiotemporal Variability ◽  
Horizontal Gradient ◽  
Particulate Pollution ◽  
Paris Area ◽  
Surface Measurements ◽  
Surface Network ◽  
Set Up ◽  
Lidar Observations ◽  
Mass Concentrations

Abstract. We investigate in this study the role of the Paris Peripherique (the ring around Paris agglomeration) in local particulate pollution and the horizontal gradient of pollution between Paris centre and its remote suburbs. For this purpose, we combine in situ surface measurements with active remote sensing observations obtained from a great number of research programs in Paris area since 1999. Two approaches, devoted to the conversion of vertical profiles of lidar-derived extinction coefficients into PM10, have been set up. A very good agreement is found between the theoretical and empirical methods with a discrepancy of 3%. Hence, specific extinction cross-sections at 355 nm are provided with a reasonable uncertainty for urban (4.5 m2/g), periurban (5.9 m2/g), rural (7.1 m2/g), biomass burning (2.6 m2/g) and dust (1.1 m2/g) aerosols. The high spatial and temporal resolutions of the mobile lidar (respectively 1.5 m and 1 min) enable to follow the spatiotemporal variability of various layers carrying aerosols in the troposphere. Appropriate specific extinction cross-sections are applied in each layer detected in the vertical heterogeneities from the lidar profiles. The standard deviation between lidar-derived PM10 at 200 m above ground and surface network stations measurements was ~14 μg m−3. This difference is particularly ascribed to a decorrelation of mass concentrations in the first meters of the boundary layer, as highlighted through multiangular lidar observations. Lidar signals can be used to follow mass concentrations at the surface and provide useful information on PM10 peak forecasting that affect air quality.

scholarly journals High-Resolution Modelling of Thermal Exposure during a Hot Spell: A Case Study Using PALM-4U in Prague, Czech Republic

Atmosphere ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 175
Author(s):  
Jan Geletič ◽  
Michal Lehnert ◽  
Pavel Krč ◽  
Jaroslav Resler ◽  
Eric Scott Krayenhoff
Keyword(s):  
Czech Republic ◽  
Urban Areas ◽  
Heat Exposure ◽  
Thermal Exposure ◽  
Urban Environments ◽  
Cooling Effect ◽  
Spatiotemporal Variability ◽  
Climate Index ◽  
Street Canyons ◽  
General Terms

The modelling of thermal exposure in outdoor urban environments is a highly topical challenge in modern climate research. This paper presents the results derived from a new micrometeorological model that employs an integrated biometeorology module to model Universal Thermal Climate Index (UTCI). This is PALM-4U, which includes an integrated human body-shape parameterization, deployed herein for a pilot domain in Prague, Czech Republic. The results highlight the key role of radiation in the spatiotemporal variability of thermal exposure in moderate-climate urban areas during summer days in terms of the way in which this directly affects thermal comfort through radiant temperature and indirectly through the complexity of turbulence in street canyons. The model simulations suggest that the highest thermal exposure may be expected within street canyons near the irradiated north sides of east–west streets and near streets oriented north–south. Heat exposure in streets increases in proximity to buildings with reflective paints. The lowest heat exposure during the day may be anticipated in tree-shaded courtyards. The cooling effect of trees may range from 4 °C to 9 °C in UTCI, and the cooling effect of grass in comparison with artificial paved surfaces in open public places may be from 2 °C to 5 °C UTCI. In general terms, this study illustrates that the PALM modelling system provides a new perspective on the spatiotemporal differentiation of thermal exposure at the pedestrian level; it may therefore contribute to more climate-sensitive urban planning.

scholarly journals Computer-aided design of multi-purpose steel headframes for mines with a new technical level

2020 ◽  
Vol 174 ◽  
pp. 01048
Author(s):  
Elena Kassikhina ◽  
Vladimir Pershin ◽  
Nina Rusakova
Keyword(s):  
Cross Sections ◽  
Computer Aided Design ◽  
Information Technologies ◽  
Three Dimensional ◽  
Numerical Control ◽  
Technical Level ◽  
Resource Saving ◽  
Existing Structures ◽  
Set Up ◽  
Aided Design

The existing structures of the steel sinking headgear and permanent headframe do not meet the requirements of resource saving (metal consumption and manpower input at installation), and the present methods of the headframe designing do not fully reflect recent possibilities of applying of the advanced information technologies. Technical level of the modern software makes it possible for designers to set up multiple numerical experiments to create a computer simulation that allows solving the problem without field and laboratory experiments, and therefore without special costs. In this regard, a mathematical simulation has been developed and based on it, software to select cross-sections of multi- purpose steel headframe elements and to calculate proper weight of its metal structures depending on the characteristics and hoisting equipment. A headframe drawing is displayed, as the results of the software work, including list of elements, obtained optimal hoisting equipment in accordance with the initial data. The software allows speeding up graphic work and reducing manpower input on calculations and paper work. The software allows developing a three-dimensional image of the structure and its functional blocks, based on the obtained initial parameters, as well as developing control software for units with numerical control (NC) in order to manufacture multi-purpose headframes.

scholarly journals Imaging the Subsurface: How Different Visualizations of Cross-sections Affect the Sense of Uncertainty

2021 ◽  
Vol 5 (1) ◽  
Author(s):  
Ane Bang-Kittilsen ◽  
Terje Midtbø
Keyword(s):  
Cross Sections ◽  
Open Data ◽  
Question Mark ◽  
Reference Information ◽  
Geological Information ◽  
Crucial Information ◽  
Set Up ◽  
Web Experiment ◽  
The Right ◽  
Visualization Techniques

AbstractGeologists struggle to communicate the uncertainty that arise when mapping and interpreting the geological subsurface. Today, open data sharing policies make new value of geological information possible for a broader user group of non-experts. It is crucial to develop standard methods for visualizing uncertainty to increase the usability of geological information. In this study, a web experiment was set up to analyze whether and how different design choices influence the sense of uncertainty. Also, questions about the intuitiveness of symbols were asked. Two-hundred ten participants from different countries completed the experiment, both experts and non-experts in geology. Traditional visualization techniques in geology, like dashed lines, dotted lines and question mark, were tested. In addition, other visualizations were tested, such as hatched area and variations of symbol size, zoom levels and reference information. The results show that design choices have an impact on the participants’ assessment of uncertainty. The experts inquire about crucial information if it is not present. The results also suggest that when visualizing uncertainty, all the elements in the representation, and specifically the line and area symbols that delineate and colour the features, must work together to make the right impression.

scholarly journals The Impact of the Minimum Wage on Male and Female Employment and Earnings in India

2017 ◽  
Vol 34 (1) ◽  
pp. 28-64 ◽  
Author(s):  
Nidhiya Menon ◽  
Yana van der Meulen Rodgers
Keyword(s):  
Minimum Wage ◽  
Cross Sections ◽  
Urban Areas ◽  
Wage Gap ◽  
National Sample ◽  
Female Employment ◽  
Sample Survey ◽  
Market Outcomes ◽  
Wage Rates ◽  
The Impact

This study examines how employment and wages for men and women respond to changes in the minimum wage in India, a country known for its extensive system of minimum wage regulations across states and industries. Using repeated cross sections of India's National Sample Survey Organization employment survey data for the period 1983–2008 merged with a newly created database of minimum wage rates, we find that, regardless of gender, minimum wages in urban areas have little to no impact on labor market outcomes. However, minimum wage rates increase earnings in the rural sector, especially for men, without any employment losses. Minimum wage rates also increase the residual gender wage gap, which may be explained by weaker compliance among firms that hire female workers.

Glass-Alumina Functionally Graded Materials Produced by Plasma Spraying

2007 ◽  
Vol 333 ◽  
pp. 227-230
Author(s):  
Valeria Cannillo ◽  
Luca Lusvarghi ◽  
Tiziano Manfredini ◽  
M. Montorsi ◽  
Cristina Siligardi ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Plasma Spraying ◽  
Functionally Graded Materials ◽  
Cross Sections ◽  
Functionally Graded ◽  
Depth Sensing ◽  
Graded Materials ◽  
Set Up ◽  
Scanning Electron

The present work was focused on glass-alumina functionally graded materials. The samples, produced by plasma spraying, were built as multi-layered systems by depositing several layers of slightly different composition, since their alumina and glass content was progressively changed. After fabricating the graded materials, several, proper characterization techniques were set up to investigate the gradient in composition, microstructure and related performances. A particular attention was paid to the observation of the graded cross sections by scanning electron microscopy, which allowed to visualize directly the graded microstructural changes. The scanning electron microscopy (SEM) inspection was integrated with accurate mechanical measurements, such as systematic depth-sensing Vickers microindentation tests performed on the graded cross sections.

scholarly journals Exploring the relation between aerosol optical depth and PM<sub>2.5</sub> at Cabauw, the Netherlands

2008 ◽  
Vol 8 (5) ◽  
pp. 17939-17986 ◽  
Author(s):  
M. Schaap ◽  
A. Apituley ◽  
R. M. A. Timmermans ◽  
R. B. A. Koelemeijer ◽  
G. de Leeuw
Keyword(s):  
The Netherlands ◽  
Ground Level ◽  
Weather Conditions ◽  
Fair Weather ◽  
Modis Aod ◽  
Data Points ◽  
Set Up ◽  
The Relationship ◽  
Lidar Observations ◽  
Pm2.5 Concentration

Abstract. To acquire daily estimates of PM2.5 distributions based on satellite data one depends critically on an established relation between AOD and ground level PM2.5. In this study we aimed to experimentally establish the AOD-PM2.5 relationship for the Netherlands. For that purpose an experiment was set-up at the AERONET site Cabauw. The average PM2.5 concentration during this ten month study was 18 μg/m3, which confirms that the Netherlands are characterised by a high PM burden. A first inspection of the AERONET level 1.5 (L1.5) AOD and PM2.5 data at Cabauw showed a low correlation between the two properties. However, after screening for cloud contamination in the AERONET L1.5 data, the correlation improved substantially. When also constraining the dataset to data points acquired around noon, the correlation between AOD and PM2.5 amounted to R2=0.6 for situations with fair weather. This indicates that AOD data contain information about the temporal evolution of PM2.5. We had used LIDAR observations to detect residual cloud contamination in the AERONET L1.5 data. Comparison of our cloud-screed L1.5 with AERONET L2 data that became available near the end of the study showed favorable agreement. The final relation found for Cabauw is PM2.5=124.5*AOD–0.34 (with PM2.5 in μg/m3) and is valid for fair weather conditions. The relationship determined between MODIS AOD and ground level PM2.5 at Cabauw is very similar to that based on the much larger dataset from the sun photometer data, after correcting for a systematic overestimation of the MODIS data of 0.05. We applied the relationship to a MODIS composite map to assess the PM2.5 distribution over the Netherlands. Spatial dependent systematic errors in the MODIS AOD, probably related to variability in surface reflectance, hamper a meaningful analysis of the spatial distribution of PM2.5 using AOD data at the scale of the Netherlands.

scholarly journals Integrated Passenger Transport System in Rural Areas – A Literature Review

2020 ◽  
Vol 32 (6) ◽  
pp. 863-873
Author(s):  
Branimir Maretić ◽  
Borna Abramović
Keyword(s):  
Literature Review ◽  
Transport System ◽  
Rural Areas ◽  
Urban Areas ◽  
Planning System ◽  
Passenger Transport ◽  
Public Transport System ◽  
Urban And Rural Areas ◽  
Set Up ◽  
The Impact

The planning and organisation of public passenger transport in rural areas is a complex process. The transport demand in rural areas is often low, which makes it hard to establish and run a financially sustainable public transport system. A solution is integrated passenger transport that eliminates deficiencies and provides benefits for all participants in the public passenger transport process. This paper describes the impact of integrated passenger transport on mobility in rural areas and critically evaluates different literature sources. Integration of passenger transport in urban areas has been described in the context of rural areas, and the challenges of integration of public passenger transport specific to rural areas have been analysed. Through the application in urban and rural areas, the planning of integrated and non-integrated passenger transport has been functionally analysed. The analysis found an increase in the degree of mobility in the areas that use integrated passenger transport compared to the non-integrated one. This research of the literature review has identified the rural areas of mobility as under-researched. The mobility research can set up a more efficient passenger transport planning system in rural areas.

scholarly journals Float: Designing for the Rise in Sea Level

2019 ◽  
Author(s):  
Camilo Cerro ◽  
Keyword(s):  
Sea Level ◽  
Urban Areas ◽  
Healthcare Education ◽  
American University ◽  
Real Possibility ◽  
Urban Problem ◽  
Will Force ◽  
Complex Relationships ◽  
Set Up ◽  
Floating Systems

According to the United Nations, presently, about 54% of the world’s population lives in urban areas, with the number expected to increase to 66% by 2050. Urban areas which are ill prepared to deal with their present population needs will have to develop and manage; housing, healthcare, education, transportation, infrastructure and food pro-duction for an additional 2.5 billion people. With three-quarters of the world’s megalopolis by the sea and 80% of people living within 60 miles of the coast, sea level rise will force a new way of thinking about urban development. Managing urban areas has become one of the most important development challenges of the 21st century. In the UAE specifically, there are nearly 1,300 kilometers of coast-line. Approximately 85% of the population and over 90% of the infra-structure are located within several meters of sea level in low-lying coastal areas. This poses a very specific urban problem of relocation. But not all relocation will need to be done inland. The potential for floating architecture is a very real possibility to help solve some of the problems brought on by the rise in sea level. This is why at the American University of Sharjah, we have been studying this issue and other sustainability related opportunities in a series of courses that started in 2014 with a summer studio course set in Cambodia. Students lived with a floating community in the Tong le Sap lake for a month, studying vernacular floatation systems to inform the development of proposals for floating dwelling studies. This semester (Spring 2018), a fifth year architecture studio set up to transfer specific urban functions to the water within protected areas in the UAE. The aim of the studio was to start looking at possible implementation of floating systems within everyday functions to start a discussion of the potential of this technologies and the feasibility of its use at both an industrial and commercial level. The idea was to develop a series systemic interdependent sustainable designs based on the idea of third nature, hybridizing complex relationships between distinct functions in environments above and below water. This paper will cover the methodology implemented to start tackling these subjects in the studio environment with the aim to create awareness for designers and the general public.

Geodetic benchmark displacement measurements following the 2020 Petrinja earthquake in Croatia

2021 ◽  
Author(s):  
Branko Kordić ◽  
Matija Vukovski ◽  
Marko Budić ◽  
Marko Špelić ◽  
Josip Barbača ◽  
...  
Keyword(s):  
Rural Areas ◽  
Urban Areas ◽  
Field Research ◽  
Future Research ◽  
Postseismic Deformation ◽  
Vertical Displacements ◽  
Geodynamic Processes ◽  
Set Up ◽  
Deformation Area ◽  
Absolute Shift

&lt;p&gt;The earthquake with magnitude ML=6.2 that occurred on 29th December 2020 has caused significant material damage to objects and infrastructure in the towns of Petrinja, Sisak,Glina and the surrounding area. According to the satellite interferometry data, the coseismic and postseismic deformation area covers around 500 square kilometers. The existing geodetic benchmarks have been set in the affected towns, and their coordinates have been determined based on previous GPS campaigns. The GPS network was set up and adjusted at the State Geodetic Administration's request for geodetic monitoring of infrastructure and cadastral projects. These points are not primarily intended for high accuracy measurements at the level of a few millimeters, so their accuracy and the absolute shift concerning geodynamic processes in the region should be taken into account. Nevertheless, the data obtained by their observation after the earthquake can provide valuable information about the horizontal and vertical displacements with a certain level of confidence. The field survey has detected disappearance of a large number of benchmarks and some valuable information has been lost. Still, 58 points were found and observed and it has been concluded that 52 points are reliable and can be used for future research. Because the network of benchmarks is not developed in rural areas, there is a gap in the distribution of benchmarks in affected area. Therefore, the additional data was collected using the benchmarks established for the engineering and cadastral projects and studies. From a total of 67 points that have been found and observed, 42 points will be used. Along with the data collected in urban areas, there will be a total of 94 benchmarks. The accuracy of the geodetic benchmark measurements is at the centimeter level, while the values of deformation are at the level of a few decimeters. Therefore, the obtained data can be used to better assess the displacement recorded during the 29 December 2020 event. In the future, field research will focus on finding additional benchmarks to reach a better spatial distribution.&lt;/p&gt;

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