scholarly journals Estimating the impact of a new bridge over the river Danube

2022 ◽  
Vol 960 (1) ◽  
pp. 012021
Author(s):  
Adrian Vilcan ◽  
Viorel Nicolae ◽  
Ivana Martin ◽  
Mihaela Istrate
Keyword(s):  
Transport Model ◽  
Road Transport ◽  
Sensitivity Tests ◽  
River Danube ◽  
Time Savings ◽  
The Impact

Abstract The impact of a new bridge over the Danube was estimated using a 3-step road transport model, as at the time no multimodal model was available. Different forecasts have been considered for both scenarios without the project and with the project. Also, sensitivity tests have been carried out in order to assess the impact of various bridge tolls. At the end, time savings and emissions have been estimated.

scholarly journals Atmospheric ethanol in London and the potential impacts of future fuel formulations

2016 ◽  
Vol 189 ◽  
pp. 105-120 ◽  
Author(s):  
Rachel E. Dunmore ◽  
Lisa K. Whalley ◽  
Tomás Sherwen ◽  
Mathew J. Evans ◽  
Dwayne E. Heard ◽  
...  
Keyword(s):  
Transport Model ◽  
Regional Scale ◽  
Road Transport ◽  
Emission Source ◽  
Chemical Mechanism ◽  
Scale Model ◽  
Chemical Transport Model ◽  
Regional Modelling ◽  
Primary Emissions ◽  
The Impact

There is growing global consumption of non-fossil fuels such as ethanol made from renewable biomass. Previous studies have shown that one of the main air quality disadvantages of using ethanol blended fuels is a significant increase in the production of acetaldehyde, an unregulated and toxic pollutant. Most studies on the impacts of ethanol blended gasoline have been carried out in the US and Brazil, with much less focus on the UK and Europe. We report time resolved measurements of ethanol in London during the winter and summer of 2012. In both seasons the mean mixing ratio of ethanol was around 5 ppb, with maximum values over 30 ppb, making ethanol currently the most abundant VOC in London air. We identify a road transport related source, with ‘rush-hour’ peaks observed. Ethanol is strongly correlated with other road transport-related emissions, such as small aromatics and light alkanes, and has no relationship to summer biogenic emissions. To determine the impact of road transport-related ethanol emission on secondary species (i.e. acetaldehyde and ozone), we use both a chemically detailed box model (incorporating the Master Chemical Mechanism, MCM) and a global and nested regional scale chemical transport model (GEOS-Chem), on various processing time scales. Using the MCM model, only 16% of the modelled acetaldehyde was formed from ethanol oxidation. However, the model significantly underpredicts the total levels of acetaldehyde, indicating a missing primary emission source, that appears to be traffic-related. Further support for a primary emission source comes from the regional scale model simulations, where the observed concentrations of ethanol and acetaldehyde can only be reconciled with the inclusion of large primary emissions. Although only constrained by one set of observations, the regional modelling suggests a European ethanol source similar in magnitude to that of ethane (∼60 Gg per year) and greater than that of acetaldehyde (∼10 Gg per year). The increased concentrations of ethanol and acetaldehyde from primary emissions impacts both radical and NOx cycling over Europe, resulting in significant regional impacts on NOy speciation and O3 concentrations, with potential changes to human exposure to air pollutants.

scholarly journals Development of a Component-Level Hydrogen Transport Model with OpenFOAM and Application to Tritium Transport Inside a DEMO HCPB Breeder

2021 ◽  
Vol 11 (8) ◽  
pp. 3481
Author(s):  
Volker Pasler ◽  
Frederik Arbeiter ◽  
Christine Klein ◽  
Dmitry Klimenko ◽  
Georg Schlindwein ◽  
...  
Keyword(s):  
Transport Model ◽  
Tritium Concentration ◽  
Minor Role ◽  
Specific Rate ◽  
Component Level ◽  
Diffusion Limited ◽  
Purge Gas ◽  
Choice Of Species ◽  
The Impact ◽  
Tritium Transport

This work continues the development of a numerical model to simulate transient tritium transport on the breeder zone (BZ) level for the EU helium-cooled pebble bed (HCPB) concept for DEMO. The basis of the model is the open-source field operation and manipulation framework, OpenFOAM. The key output quantities of the model are the tritium concentration in the purge gas and in the coolant and the tritium inventory inside the BZ structure. New model features are briefly summarized. As a first relevant application a simulation of tritium transport for a single pin out of the KIT HCPB design for DEMO is presented. A variety of scenarios investigates the impact of the permeation regime (diffusion-limited vs. surface-limited), of an additional hydrogen content of 300 Pa H2 in the purge gas, of the released species (HT vs. T2), and of the choice of species-specific rate constants (recombination constant of HT set twice as for H2 and T2). The results indicate that the released species plays a minor role for permeation. Both permeation and inventory show a considerable dependence on a possible hydrogen addition in the purge gas. An enhanced HT recombination constant reduces steel T inventories and, in the diffusion-limited case, also permeation significantly. Scenarios with 80 bar vs. 2 bar purge gas pressure indicate that purge gas volumetric flow is decisive for permeation.

scholarly journals Assessment of Spatiotemporal Peak Shift of Intra-Urban Transportation Taking a Case in Bangkok, Thailand

2021 ◽  
Vol 13 (12) ◽  
pp. 6777
Author(s):  
Masanobu Kii ◽  
Yuki Goda ◽  
Varameth Vichiensan ◽  
Hiroyuki Miyazaki ◽  
Rolf Moeckel
Keyword(s):  
Developing Countries ◽  
Travel Time ◽  
Demand Management ◽  
Likelihood Estimation ◽  
Road Transport ◽  
Peak Shift ◽  
Time Shift ◽  
Peak Time ◽  
Management Scenarios ◽  
The Impact

Reducing congestion has been one of the critical targets of transportation policies, particularly in cities in developing countries suffering severe and chronic traffic congestions. Several traditional measures have been in place but seem not very successful. This paper applies the agent-based transportation model MATSim for a transportation analysis in Bangkok to assess the impact of spatiotemporal transportation demand management measures. We collect required data for the simulation from various data sources and apply maximum likelihood estimation with the limited data available. We investigate two demand management scenarios, peak time shift, and decentralization. As a result, we found that these spatiotemporal peak shift measures are effective for road transport to alleviate congestion and reduce travel time. However, the effect of those measures on public transport is not uniform but depends on the users’ circumstances. On average, the simulated results indicate that those measures increase the average travel time and distance. These results suggest that demand management policies require considerations of more detailed conditions to improve usability. The study also confirms that microsimulation can be a tool for transport demand management assessment in developing countries.

scholarly journals The Environmental Effects of the April 2020 Wildfires and the Cs-137 Re-Suspension in the Chernobyl Exclusion Zone: A Multi-Hazard Threat

Atmosphere ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 467
Author(s):  
Rocío Baró ◽  
Christian Maurer ◽  
Jerome Brioude ◽  
Delia Arnold ◽  
Marcus Hirtl
Keyword(s):  
Air Quality ◽  
Nuclear Power ◽  
Transport Model ◽  
Atmospheric Transport ◽  
Point Of View ◽  
Plume Dispersion ◽  
Exclusion Zone ◽  
Fire Plume ◽  
Mean Values ◽  
The Impact

This paper demonstrates the environmental impacts of the wildfires occurring at the beginning of April 2020 in and around the highly contaminated Chernobyl Exclusion Zone (CEZ). Due to the critical fire location, concerns arose about secondary radioactive contamination potentially spreading over Europe. The impact of the fire was assessed through the evaluation of fire plume dispersion and re-suspension of the radionuclide Cs-137, whereas, to assess the smoke plume effect, a WRF-Chem simulation was performed and compared to Tropospheric Monitoring Instrument (TROPOMI) satellite columns. The results show agreement of the simulated black carbon and carbon monoxide plumes with the plumes as observed by TROPOMI, where pollutants were also transported to Belarus. From an air quality and health perspective, the wildfires caused extremely bad air quality over Kiev, where the WRF-Chem model simulated mean values of PM2.5 up to 300 µg/m3 (during the first fire outbreak) over CEZ. The re-suspension of Cs-137 was assessed by a Bayesian inverse modelling approach using FLEXPART as the atmospheric transport model and Ukraine observations, yielding a total release of 600 ± 200 GBq. The increase in both smoke and Cs-137 emissions was only well correlated on the 9 April, likely related to a shift of the focus area of the fires. From a radiological point of view even the highest Cs-137 values (average measured or modelled air concentrations and modelled deposition) at the measurement site closest to the Chernobyl Nuclear Power Plant, i.e., Kiev, posed no health risk.

scholarly journals Modular Approach to Ultra-fast Charging Stations

2021 ◽  
Author(s):  
Carola Leone ◽  
Michela Longo
Keyword(s):  
Impact Analysis ◽  
Road Transport ◽  
Modular Approach ◽  
Long Distance ◽  
Charging Infrastructure ◽  
Charging Station ◽  
Fast Charging ◽  
Modular Architectures ◽  
The Impact ◽  
Fast Charging Station

AbstractRoad transport electrification is essential for meeting the European Union's goals of decarbonization and climate change. In this context, an Ultra-Fast Charging (UFC) system is deemed necessary to facilitate the massive penetration of Electric Vehicles (EVs) on the market; particularly as medium-long distance travels are concerned. Anyway, an ultra-fast charging infrastructure represents the most critical point as regards hardware technology, grid-related issues, and financial sustainability. Thus far, this paper presents an impact analysis of a fast-charging station on the grid in terms of power consumption, obtained by the Monte Carlo simulation. Simulation results show that it is not economical convenient size the assumed ultra-fast charging station for the maximum possible power also considering its high impact on the grid. In view of the results obtained from the impact analysis, the last part of the paper focuses on finding a method to reduce the power installed for the DC/DC stage while keeping the possibility for the electric vehicle to charge at their maximum power. To achieve this goal a modular approach is proposed. Finally, two different modular architectures are presented and compared. In both the solutions, the probability of having EVs charging at limited power is less than 5%.

scholarly journals A Comparative Analysis of the Government and NGOs in Delivering Quality Services for the Rural People of Pakistan: Community Perspectives

2020 ◽  
Vol 30 (1-2) ◽  
pp. 203-225
Author(s):  
Mohsin Khan ◽  
Jetnor Kasmi ◽  
Abdul Saboor ◽  
Iftikhar Ali
Keyword(s):  
Drinking Water ◽  
Service Delivery ◽  
Rural Areas ◽  
Public Health Education ◽  
Road Transport ◽  
Extension Services ◽  
Rural People ◽  
Basic Services ◽  
The Government ◽  
The Impact

Often the government and the non-governmental organisations (NGOs) are criticised for their poor performances in delivering services particularly in rural areas. However, there has been limited research on the assessment of their relative performances in service delivery as well as on the perceptions of people on the quality of such service delivery. This study examines the relative performances of NGOs and the governmental development interventions that provide basic services including public health, education, drinking water and sanitation. The study explains the impact of agricultural extension services and infrastructure such as access to roads and markets on the rural people and measures the satisfaction level of the rural community. For this purpose, 225 households (HHs) in 8 villages of Phalia Tehsil, district Mandi Bahauddin, Punjab, Pakistan were first surveyed in 2010 and then in 2014 using a structured questionnaire. The findings reveal different satisfaction levels of HHs, with most of them expressing less satisfaction on government service delivery compared with NGOs. They reveal satisfaction over the performance of NGOs in health, drinking water supplies and agriculture extension services. Further, the study shows an increasing satisfaction of people on access to road, transport, agri-market and price of agri-commodities by the government.

scholarly journals Nitrogen Mass Balance and Pressure Impact Model Applied to an Urban Aquifer

Water ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 1171 ◽  
Author(s):  
Mitja Janža ◽  
Joerg Prestor ◽  
Simona Pestotnik ◽  
Brigita Jamnik
Keyword(s):  
Groundwater Quality ◽  
Urban Areas ◽  
Transport Model ◽  
Nitrate Concentration ◽  
Impact Model ◽  
Sewer System ◽  
Management Measures ◽  
Pressure Impact ◽  
The Impact ◽  
The City

The assurance of drinking water supply is one of the biggest emerging global challenges, especially in urban areas. In this respect, groundwater and its management in the urban environment are gaining importance. This paper presents the modeling of nitrogen load from the leaky sewer system and from agriculture and the impact of this pressure on the groundwater quality (nitrate concentration) in the urban aquifer located beneath the City of Ljubljana. The estimated total nitrogen load in the model area of 58 km2 is 334 ton/year, 38% arising from the leaky sewer system and 62% from agriculture. This load was used as input into the groundwater solute transport model to simulate the distribution of nitrate concentration in the aquifer. The modeled nitrate concentrations at the observation locations were found to be on average slightly lower (2.7 mg/L) than observed, and in general reflected the observed contamination pattern. The ability of the presented model to relate and quantify the impact of pressures from different contamination sources on groundwater quality can be beneficially used for the planning and optimization of groundwater management measures for the improvement of groundwater quality.

scholarly journals The Impact of Financial and Non-Financial Work Incentives on the Safety Behavior of Heavy Truck Drivers

2021 ◽  
Vol 18 (5) ◽  
pp. 2759
Author(s):  
Sebastjan Škerlič ◽  
Vanja Erčulj
Keyword(s):  
Financial Incentives ◽  
Structural Equation ◽  
Traffic Accidents ◽  
Positive Impact ◽  
Road Transport ◽  
Truck Drivers ◽  
Driving Ability ◽  
Transport Sector ◽  
Safety Behavior ◽  
The Impact

The goal of the research is to determine how compensation affects the safety behavior of truck drivers and consequently the frequency of traffic accidents. For this purpose, a survey was conducted on a sample of 220 truck drivers in international road transport in the EU, where the results of the Structural Equation Model (SEM) show that in the current state of the transport sector, financial and non-financial incentives have a positive impact on the work and safety behavior of drivers. Financial incentives also have an impact on drivers’ increased perception of their driving ability, while moving violations continue to have a major impact on the number of accidents. The proposed improvements enable decision-makers at the highest level to adopt legal solutions to help manage the issues that have been affecting the industry from a work, social and safety point of view for the past several years. The results of the research therefore represent an important guideline for improvements to the legislature as well as in the systematization of truck driver compensation within companies.

The measurement of groundwater temperature in shallow piezometers and standpipes

2005 ◽  
Vol 42 (5) ◽  
pp. 1377-1390 ◽  
Author(s):  
Matthew D Alexander ◽  
Kerry TB MacQuarrie
Keyword(s):  
Finite Element ◽  
Statistical Analysis ◽  
Transport Model ◽  
Shallow Groundwater ◽  
Subsurface Temperature ◽  
Groundwater Temperature ◽  
Monitoring Well ◽  
Laboratory Results ◽  
The Impact

Accurate measurements of in situ groundwater temperature are important in many groundwater investigations. Temperature is often measured in the subsurface using an access tube in the form of a piezometer or monitoring well. The impact of standpipe materials on the conduction of heat into the subsurface has not previously been examined. This paper reports on the results of a laboratory experiment and a field experiment designed to determine if different standpipe materials or monitoring instrument configurations preferentially conduct heat into the shallow sub surface. Simulations with a numerical model were also conducted for comparison to the laboratory results. Statistical analysis of the laboratory results demonstrates that common standpipe materials, such as steel and polyvinylchloride (PVC), do not affect temperature in the subsurface. Simulations with a finite element flow and heat transport model also confirm that the presence of access tube materials does not affect shallow groundwater temperature measurements. Field results show that different instrument configurations, such as piezometers and water and air filled and sealed well points, do not affect subsurface temperature measurements.Key words: groundwater temperature, temperature measurement, conduction, piezometers, piezometer standpipes, thermal modelling.

Impact of the Depth-to-Width Ratio of Periodically Stratified Tidal Channels on the Estuarine Circulation

2015 ◽  
Vol 45 (8) ◽  
pp. 2048-2069 ◽  
Author(s):  
Elisabeth Schulz ◽  
Henk M. Schuttelaars ◽  
Ulf Gräwe ◽  
Hans Burchard
Keyword(s):  
Eddy Viscosity ◽  
Transport Model ◽  
Stable Stratification ◽  
Estuarine Circulation ◽  
Width Ratio ◽  
Cross Sectional ◽  
Tidal Straining ◽  
The Individual ◽  
Periodic Stratification ◽  
The Impact

AbstractThe dependency of the estuarine circulation on the depth-to-width ratio of a periodically, weakly stratified tidal estuary is systematically investigated here for the first time. Currents, salinity, and other properties are simulated by means of the General Estuarine Transport Model (GETM) in cross-sectional slice mode, applying a symmetric Gaussian-shaped depth profile. The width is varied over four orders of magnitude. The individual along-channel circulation contributions from tidal straining, gravitation, advection, etc., are calculated and the impact of the depth-to-width ratio on their intensity is presented and elucidated. It is found that the estuarine circulation exhibits a distinct maximum in medium-wide channels (intermediate depth-to-width ratio depending on various parameters), which is caused by a maximum of the tidal straining contribution. This maximum is related to a strong tidal asymmetry of eddy viscosity and shear created by secondary strain-induced periodic stratification (2SIPS): in medium channels, transverse circulation generated by lateral density gradients due to laterally differential longitudinal advection induces stable stratification at the end of the flood phase, which is further increased during ebb by longitudinal straining (SIPS). Thus, eddy viscosity is low and shear is strong in the entire ebb phase. During flood, SIPS decreases the stratification so that eddy viscosity is high and shear is weak. The circulation resulting from this viscosity–shear correlation, the tidal straining circulation, is oriented like the classical, gravitational circulation, with riverine outflow at the surface and oceanic inflow close to the bottom. In medium channels, it is about 5 times as strong as in wide (quasi one-dimensional) channels, in which 2SIPS is negligible.

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