Getting Real: The Challenge of Building and Validating a Large-Scale Digital Twin of Barcelona’s Traffic with Empirical Data

Large-scale microsimulations are increasingly resourceful tools for analysing in detail citywide effects and alternative scenarios of our policy decisions, approximating the ideal of ‘urban digital twins’. Yet, these models are costly and impractical, and there are surprisingly few published examples robustly validated with empirical data. This paper, therefore, presents a new large-scale agent-based traffic microsimulation for the Barcelona urban area using SUMO to show the possibilities and challenges of building these scenarios based on novel fine-grained empirical big data. It combines novel mobility data from real cell phone records with conventional surveys to calibrate the model comparing two different dynamic assignment methods for getting an operationally realistic and efficient simulation. Including through traffic and the use of a stochastic adaptive routing approach results in a larger 24-hour model closer to reality. Based on an extensive multi-scalar evaluation including traffic counts, hourly distribution of trips, and macroscopic metrics, this model expands and outperforms previous large-scale scenarios, which provides new operational opportunities in city co-creation and policy. The novelty of this work relies on the effective modelling approach using newly available data and the realistic robust evaluation. This allows the identification of the fundamental challenges of simulation to accurately capture real-world dynamical systems and to their predictive power at a large scale, even when fed by big data, as envisioned by the digital twin concept applied to smart cities.

Heights of Cb clouds around Chhatrapati Shivaji International (C.S.I.) airport, Mumbai - Diurnal and seasonal variations

Lkkj & bl 'kks/k&i= esa 1990&99 ds o"kksZa ds nkSjku ekSle dk;kZy;] N=ifr f’kokth vUrjjk"Vªh; ¼lh- ,l- vkbZ-½ gokbZ vM~Ms esa ,df=r fd, x, jsMkj ds vk¡dM+ksa ds vk/kkj ij gokbZ vM~Ms ds lehi 200 fd- eh- dh ifjf/k esa 6 fd- eh- ls Åij vFkok blls vkSj vf/kd Å¡pkbZ ij QSys diklh es?kksa ¼lh- ch-½ dk v/;;u fd;k x;k gSA blesa lh- ch- lSyksa dh dqy la[;k ds ekSleh] ekfld vkSj ?kaVsokj forj.k vkSj mudh Å¡pkb;ksa] lh- ch- lfgr fnuksa dh la[;k] {kksHkeaMyh; lhek dh Å¡pkbZ rd igq¡pus okys lh- ch- lSyksa] foiqy lh- ch- es?kksa ds cuus ds izkFkfedrk okys LFkkuksa vkSj mudh xfr dh tk¡p djds mu ij fopkj&foe’kZ fd;k x;k gSA lh- ,l- vkbZ- gokbZ vM~Ms eqEcbZ ds lehi lh- ch- es?kksa ds fodkl ds fy, mÙkjnk;h flukfIVd fLFkfr;ksa dk Hkh irk yxk;k x;k gS vkSj mu ij fopkj&foe’kZ Hkh fd;k x;k gSA Based on radar data collected at the Meteorological Office, Chhatrapati Shivaji International (C.S.I.) airport, Mumbai during the years 1990-99, a study has been made on cumulonimbus (Cb) clouds with their height of top 6 km or more over an area having a radius of 200 km around the airport. The seasonal, monthly and hourly distribution of the total number of Cb cells and their heights, number of days with Cb, Cb cells that reached tropopause height, the preferred places of formation of large Cb clouds and their movement have been examined and discussed. The synoptic situation(s) responsible for the development of Cb clouds around C.S.I. airport, Mumbai have also been identified and discussed.

Analysis of the Wind Turbine Selection for the Given Wind Conditions

The aim of the current paper is to present an approach to a wind turbine selection based on an annual wind measurements. The proposed approach led to a choice of an optimal device for the given wind conditions. The research was conducted for two potential wind farm locations, situated on the north of Poland. The wind measurements pointed out a suitability of the considered localizations for a wind farm development. Six types of wind turbines were investigated in each localization. The power of the wind turbines were in the range of 2.0 to 2.5 MW and with a medium size of the rotor being in the range of 82 to 100 m. The purpose of the research was to indicate a wind turbine with the lowest sensitivity to the variation of wind speed and simultaneously being most effective energetically. The Weibull density distribution was used in the analyses for three values of a shape coefficients k. The energy efficiency of the considered turbines were also assessed. In terms of the hourly distribution of the particular wind speeds, the most effective wind turbines were those with a nominal power of 2 MW, whereas the least effective were those with the nominal power of 2.3–2.5 MW. The novelty of the proposed approach is to analyze the productivity for many types of wind turbines in order to select the one which is the most effective energy producer. The analyses conducted in the paper allowed to indicate a wind turbine which generates the highest amount of energy independently on the wind speed variation.

Identifying the critical orientation of wood-frame walls in assessing moisture risks using hygrothermal simulation

Hygrothermal simulations can be used as a reliable tool in analysing moisture performance. For an efficient analysis, it is important to appropriately select the wall orientation in the simulations. ASHRAE 160 recommends to using orientation with highest amount of annual wind-driven rain (WDR) and the orientation with the least annual solar radiation. The objective of this work was to identify the orientation which leads to the worst moisture performance of different wall assemblies under historical climate in different Canadian cities. Four cardinal orientations (North, East, South, and West) and orientation receiving the highest amount of annual WDR (Default) were tested in this study. The simulations were carried out assuming three scenarios of moisture loads for four different wood-frame (2×6 wood stud) wall systems that differ by their claddings: brick, fibreboard, stucco, and vinyl. With an assumption of no WDR, north facing wall always leads to the worst moisture performance. In the presence of WDR, with and without water source, default orientation leads to the worst moisture performance with few exceptions. As default orientation was based on total sum of WDR, it sometimes may not lead to worst performance and hence hourly distribution of WDR should be taken into consideration.

Peculiarities of training specialists in the field of physical education and sports in higher education institutions of modern Romania

The article considers the peculiarities of training in the field of physical education and sports at specialized faculties on the example of Alexandru Ioan Cuza University. Iasi, highlighted and characterized the main provisions of the charter of the faculty, curriculum and study programs, etc. It is determined that the faculty provides training in the specialties "Physical Education and Sports", "Physical Therapy" and "Sports and Physical Activity" (bachelor); "Fitness and body aesthetics", "Leisure and extreme sports", "Therapeutic physical training in sports traumatology", "Physiotherapy in sports traumatology" (Chisinau, Republic of Moldova) and "School physical education and sports" (master's degree) future teachers of physical education and sports, coaches, physiotherapists, sports instructors, etc. The content and structure of syllabuses for the preparation of licensees / bachelors and masters are analyzed, the topics of lectures, seminars and practical academic classes are published, the hourly distribution is determined.

Analysis and Determination of Axle Load Spectra and Traffic Input for Pavement Design

This study examines the vehicle class distribution, hourly distribution factors, weekly distribution factors, monthly distribution factors, axle load spectra for each vehicle class, and each axle of each vehicle class for the WIM station installed on the N-55 highway to aid analysis and design of new Mechanistic-Empirical Pavement Design Guide. The maximum, minimum and permissible load limit for the different vehicle class, average gross vehicle weight (GWV) and permissible load limits also being incorporated. The directional distribution for north bound and south bound traffic were observed to be almost 50% for both directions, except for 5 axle trucks which was 74% for north bound and 26% for south bound. The truck class most prevalent on the highway were identified to be 3-axle tandem truck (47.50%) and also it was observed that 94.1% of this vehicle class carried load above permissible limits. Keywords: Traffic characteristics, Load distribution factor, Axle Load Spectra.

Patients Left Without Being Seen in the Emergency Department – A Retrospective Observational Patient Record Study

BackgroundThe share of patients leaving the emergency department without being seen by a physician (LWBS) is an important efficacy marker of emergency departments around the world. It has not however, been of special research interest in the Nordic countries. In this study, we assessed the LWBS rate in Kanta-Häme Central Hospital, in Hämeenlinna, Finland. Secondarily, we gathered information of LWBS patients along with all ED patients.MethodsIn this retrospective observational patient record study, our primary aim was to assess the LWBS rate of all patient visits (n = 41,631) over a 12-month period in a mid-sized Finnish secondary hospital ED. Alongside, we gathered specific information, such as age, gender, time of day and year for attendance, reason for attendance, return to healthcare and mortality after 7 and 30 days and after one year to show characteristics of LWBS patients. We present data and hourly distribution of the LWBS patients against all patient visits to the ED.ResultsA total of 305 LWBS cases were identified, leading to an LWBS rate of 0.73 %. Most LWBS took place during afternoon hours, when the ED was most crowded and waiting times were longest. Among LWBS patients, minor traumas and non-specific pain were the most common reasons for attending. Mortality among LWBS patients was naught (0.0 %) over a one-year follow-up.ConclusionsThe LWBS rate in the Kanta-Häme Central Hospital ED was low. Higher LWBS rate coincided with rush hours and longer waiting times. The proportion of minor traumas was greater than in some earlier studies. These results support the implementation of a fast track line for minor traumas in the ED.

The Micrometeorology of the Haifa Bay Area and Mount Carmel during the Summer

The Haifa bay area (HBA), which includes Mount Carmel and the Zevulun valley is the third largest metropolitan area in Israel. It is also a centre of heavy industry and an important transportation hub which serve as sources of local anthropogenic pollution. Such sources are associated with adverse health effects. In order to estimate the possible exposure of the inhabitants in such heterogeneous orographic area, a detailed atmospheric transport and dispersion modelling study is required, which in turn must take into account the local micrometeorology. The aim of this study is to conduct a spatio-temporal analysis of the flow field in the HBA in order to identify the common patterns of the average wind and characterize the statistical parameters of turbulence in this area, essential for detailed pollutants dispersion modelling. This study analyses data collected during four months of summer in a network of 16 weather stations which extend across Mount Carmel and the Zevulun valley. It was found that, during the evening and night time on Mount Carmel, different flow patterns may develop on each side, separated by the watershed line. When such conditions do not develop, as well as during the daytime, the wind field, both on Mount Carmel and the Zevulun valley is approximately homogenous. The analysis of the Monin–Obukhov similarity theory functions for the velocity standard deviations show a distinct difference between Mount Carmel and the Zevulun valley, as well as between strong and weak winds. This difference can be clearly seen also in the diurnal hourly distribution of atmospheric stabilities which exhibit higher proportions of unstable conditions in the Zevulun valley during day time and higher proportion of stable stratifications at the Mount Carmel during night-time.

Improvement of the simulation of high and low flows in the LSM based hydrological modeling chain SASER applied to the Ebro river basin

<p>The SASER (Safran-Surfex-Eaudysee-Rapid) hydrological modeling chain is a physically-based and distributed hydrological model that has been implemented over two domains: Iberia and the Pyrenees. Currently, it is used for drought studies (HUMID project) and water resources analysis (PIRAGUA project).</p><p>In this modeling chain, SAFRAN provides the meteorological forcing, SURFEX is the LSM that performs the water and energy balances and Eaudyssée-RAPID simulates daily streamflow. SAFRAN and SURFEX are run at a spatial resolution of 5 km for the Iberian implementation and 2.5 km for the Pyrenean one. Daily streamflow is calculated by the RAPID river routing scheme at a spatial resolution of 1 km in both cases. SAFRAN analyzes daily observed precipitation, which is then interpolated to the hourly scale. For precipitation, relative humidity is currently used to hourly distribute the daily precipitation.</p><p>SASER is able to simulate adequate streamflow on the Ebro basin (KGE>0.5 on 62% of near-natural gauging stations when the LSM is run at 2.5 km of spatial resolution). However, due to the lack of a hydrogeological model, low flows are often poorly reproduced by this scheme. Furthermore, peak flows could also be improved.</p><p>This work aims at improving high and lows by correcting the distribution of hourly precipitation and adding linear reservoirs to improve low flows.</p><p>The increase of the spatial resolution from 5 to 2.5 km has caused a relevant improvement of peak flows. However, most of the peak flows are still underestimated. One way of improving simulated streamflow is improving the hourly distribution of the precipitation, as SAFRAN distributes precipitation through the day with unrealistic low hourly intensities. This will impact runoff generation and, thus, peak flow. We have used two ERA-Interim driven RCM simulations from the CORDEX project to improve the hourly distribution of precipitation. As a result, we now produce more realistic temporal patterns of hourly precipitation.</p><p>The current SASER implementation is not able to sustain low flows. A physical-based solution (hydrogeological model) would be desirable, but as it is difficult to implement we chose to introduce a linear reservoir, following the steps of Artinyan et al (2008) and Getinara et al. (2014). The reservoir is able to improve low flows in most near-natural subbasins. The challenge now is how to set its parameters in non-natural basins.</p>

COVID-19 Preventive Measures & their Impact on Traffic Demand & Safety

COVID-19 has affected the mobility of people significantly due to movement restrictions imposed by government authorities to control the spread of the pandemic. The staged movement restrictions that have been implemented by the government authorities to curb the spread of the disease included the closure of educational institutions and adopt online-based education, restrict commercial activities, and reducing the number of employees at the workplace. This paper presents the impact of these mitigation policies on the traffic volumes, the number of traffic violations, and the number of crashes in the State of Qatar. The hourly distribution of traffic volume showed similar trends before and after the implementation of these policies. Overall, the total traffic decreased by 30% compared to baseline conditions for all selected intersections as well as the Central Business District (CBD) screenline after the implementation of all measures. From the safety perspective, the total traffic violations decreased by 73% in April and May when the restrictions due to all three policies were imposed. During the same time, a decrease of 42% to 54%, 20% to 54%, and around 36% was observed for traffic crashes involving deaths, major loss, and minor damages respectively. Similarly, the total traffic crashes declined by 37% when complete restrictions were in place and COVID-19 was in peak stage. The results of this study will help policymakers and planners to plan/manage the traffic operations in the future during any emergencies. The results can be applied also while managing traffic during the post-Covid era, special and mega-events for temporary traffic management based on real-life data.