scholarly journals Evaluation of the relative roles of a vegetative filter strip and a biofiltration swale in a treatment train for road runoff

2016 ◽  
Vol 75 (4) ◽  
pp. 987-997 ◽  
Author(s):  
Kelsey Flanagan ◽  
Philippe Branchu ◽  
David Ramier ◽  
Marie-Christine Gromaire

In order to determine the relative importance of a vegetative filter strip and a biofiltration swale in a treatment train for road runoff, US EPA Storm Water Management Model was used to model infiltration and runoff from the filter strip. The model consisted of a series of subcatchments representing the road, the filter strip and the side-slopes of the swale. Simulations were carried out for different rain scenarios representing a variety of climatic conditions. In addition, a sensitivity analysis was conducted for the model's different parameters (soil characteristics and initial humidity, roughness, geometry, etc.). This exercise showed that for the system studied, the majority of road runoff is treated by the filter strip rather than the biofiltration swale, an effect observed especially during periods of low-intensity rainfall. Additionally, it was observed that the combination of infiltration of road runoff in the filter strip and direct rainfall on the system leads to a significant and variable dilution of the runoff reaching the swale. This result has important implications for evaluating the treatment efficiency of the system.

Chemosphere ◽  
2005 ◽  
Vol 61 (5) ◽  
pp. 717-725 ◽  
Author(s):  
Monica Vianello ◽  
Costantino Vischetti ◽  
Luciano Scarponi ◽  
Giuseppe Zanin

Author(s):  
Palanisamy R ◽  
PLS Sai Kumar ◽  
Mekala Paavan Kiran ◽  
Ashutosh Mahto ◽  
Md. Irfan ◽  
...  

<p>Often modern cars have a collision avoidance system built into them known as Pre-Crash System, or Collision Mitigation System in order to reduce the collision. But majority of vehicles on the road, especially heavy motor vehicles lack in such a system. In this paper, the implementation of the Collision Avoidance System is to reduce the risks of collisions at the hairpin bend on a Hilly track, Ghats, or other Zero visibility turns. The proposed system contains a set of IR sensors, LEDs, etc. It uses four IR sensors, which are placed on either side of the hairpin bend. The sensors are mutually exclusive and are connected to LEDs through wires. Based on the output of sensors, the LEDs will glow and start alerting the other vehicle approaching from the other end, Hence the drivers will decrease their speeds which would help in preventing collision. The LEDs will help the drivers in detecting the position of  the vehicles on either side of the bend. During climatic conditions like fog, snow, etc, the visibility of the drivers would decrease due to which they will not be able to see the LEDs, Hence, a collision may take place. To bring help as soon as possible to the injured, we have also made a proposed system which would alert the nearby hospitals that an accident has taken place. We have used Arduino UNO, GSM sim module and these will be kept inside a black box which will be inside the, car safe from breakage during the accident.<strong></strong></p>


2021 ◽  
Author(s):  
Qiyue Hu ◽  
Song Zhu ◽  
Zanfang Jin ◽  
Aijing Wu ◽  
Xiaoyu Chen ◽  
...  

Abstract Increased nitrogen (N) from urban stormwater runoff aggravates the deterioration of aquatic ecosystems as urbanisation develops. In this study, the sources and transport of nitrate (NO3−) in urban stormwater runoff were investigated by analysing different forms of N, water isotopes (δD-H2O and δ18O-H2O), and NO3− isotopes (δ15N-NO3− and δ18O-NO3−) in urban stormwater runoff in a residential area in Hangzhou, China. The results showed that the concentrations of total N and nitrate N in road runoff were higher than those in roof runoff. Moreover, high concentrations of dissolved organic N and particulate N in road runoff led to significantly different TN concentrations in road runoff (mean: 3.76 mg/L) and roof runoff (mean: 1.23 mg/L). The high δ18O-NO3− values (mean: 60 ± 13.1‰) indicated that atmospheric deposition was the predominant NO3− source in roof runoff, as confirmed by the Bayesian isotope mixing model (SIAR model), contributing 83.6–97.8% to NO3−. The SIAR model results demonstrated that atmospheric deposition (34.2–91.9%) and chemical fertilisers (6.27–54.3%) were the main NO3− sources for the road runoff. The proportional contributions from soil and organic N were smaller than other sources in both the road runoff and roof runoff. For the initial period, the NO3− contributions from atmospheric deposition and chemical fertilisers were higher and lower, respectively, than those in the middle and late periods in road runoff during storm events 3 and 4, while an opposite trend of road runoff in storm event 7 highlighted the influence of short antecedent dry weather period. It was suggested that reducing impervious areas and more effective management of fertiliser application in urban green land areas were essential to minimize the presence of N in urban aquatic ecosystems.


2020 ◽  
Vol 264 (4) ◽  
pp. 40-46
Author(s):  
Viktor Zolotaryov ◽  
◽  
Yan Pyrig ◽  
Andrey Galkin ◽  
◽  
...  

The first Ukrainian standard ДСТУ 4044 “Viscous petroleum road bitumens. Technical conditions” was implemented in 2002. According to its content and list of indicators, it met the level of the oil refining industry of Ukraine and the state of the road industry. In addition to conventional indicators, it included additional indicators of adhesion and mass content of paraffins. The indicator for paraffin remained unregulated, because there was neither acceptable method nor necessary equipment, and in generally an intention of manufacturers and users to apply it. The standard referred to in the article differs from the previous one by the principle of assigning indicators and their list. This is largely due to Ukraine’s accession to the European Free Trade Association and the deepening of scientific knowledge on predicting the behavior of bitumen under different conditions and their impact on the properties of asphalt concrete. Accordingly, the limits of normalization of bitumen grades on the depth of needle penetration were changed, which led to an increase in amount of grades from 4 to 5. Using the dependence of the penetration index on the softening point temperature, its new normative values are ordered. The Fraas breaking temperature provided by the standard is slightly lower than that normalized EN 12591 which is due the climatic conditions of Ukraine. The rate of adhesion of bitumen to the surface is normalized, which quantitatively characterizes the adhesion of bitumen to the mineral substrate, the least favorable for interaction. It is proposed to determine the indicators of technological aging by the RTFOT method. The standard contains additional indicators to be determined according to the harmonized European standards ДСТУ EN 12607-1 and ДСТУ EN 13302 (methods for determining the dynamic viscosity). Additional standards include equal viscous heating temperatures of bitumen in the production of asphalt mixtures and their compaction. The first is the temperature, which corresponds to a bitumen viscosity of 0.5 Pas, the second is 10 Pas. Elongation at a temperature of 0 ºC is included in the standard as a certain analogue of the breaking temperature. Based on the fact that at this time the next European standard is in the final stage before approval, the values of additional indicators can be included into this standard after adjusting their values with European ones based on the characteristics of bitumen used in Ukraine. Keywords: bitumen, depth of needle penetration, softening point temperature, adhesion, ductility, cohesion, heating.


2017 ◽  
Vol 57 (36) ◽  
pp. 459
Author(s):  
Jorge A. Díaz-Pérez ◽  
Alcides C. Sampedro-Marín ◽  
Martha P. Ramírez-Pinilla

Despite its success as an invasive species, little is known about the ecological aspects of the gekkonid lizard Hemidactylus frenatus in Colombia. In the present study the size at maturity, sexual dimorphism, reproductive activity, and diet composition of a population of this species in an urban locality of Northern Colombia were determined. We conducted eleven samplings from September 2011 to August 2012 in buildings of the municipality of Sincelejo. A total of 264 specimens H. frenatus were captured, 112 were adult females, 133 adult males and 19 juveniles. Males reach sexual maturity at a smaller size (snout-vent length) than females (males: 35.7 mm; females: 42.7 mm), also they are larger and have proportionally larger heads and mouths than females. Males were reproductive throughout the year; although testicular volume varied significantly between samples, this variation was not associated with body size and precipitation in the study area. Reproductive adult females were found during all the sampling period. Females have an invariable clutch size of two eggs and we found no differences in the diameter and weight of eggs in each oviduct. The diet of H. frenatus is varied, with Diptera, Hemiptera and Formicidae being the prey types with the greatest relative importance values. Individuals of both sexes consume a similar volume and number of prey. Thus, the studied population of H. frenatus has continuous reproductive activity and a generalist-opportunistic feeding behavior. The climatic conditions of the study area, environmental availability of prey and intrinsic features of this species appear to be responsible for their abundance and colonizing success in this and other localities.


1996 ◽  
Vol 12 (1) ◽  
pp. 31-38 ◽  
Author(s):  
D. R. Edwards ◽  
T. C. Daniel ◽  
P. A. Moore Jr.

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