scholarly journals Evaluation of dynamics of atmospheric air pollution of the city center by emissions of the road transport using cartographic method

2020 ◽  
pp. 81-89
Author(s):  
A.A. Dementyev ◽  
◽  
A.M. Tsurgan ◽  
N.V. Chudinin ◽  
D.A. Soloviev ◽  
...  
Keyword(s):  
Heavy Traffic ◽  
Free Access ◽  
Traffic Flows ◽  
Vehicle Exhaust ◽  
City Center ◽  
Exhaust Gases ◽  
Traffic Conditions ◽  
Main Components ◽  
The City ◽  
Heavy Traffic Conditions

When characterizing vehicle emissions, as a rule, the speed of traffic flows is not taken into account, which significantly reduces its accuracy. In this regard, the use of the cartographic method for assessing the speed of traffic flows on the tracks is quite reasonable and relevant. The assessment of the intra-annual dynamics of the intensity of traffic flows and emissions of the main components of exhaust gases by vehicles on the streets of the city of Ryazan and bypass roads using a cartographic method for recording the intensity of traffic flows was carried out. The study was conducted in 2018–2019 on the territory of Ryazan. The material used for the study was cartographic data published in free access on the website www.yandex.ru traffic jams. The length of traffic flows with a speed of 5-10 km / h (heavy traffic conditions – TTU) was determined at different times of the day on days of the week. The indicators of the average hourly length of heavy transport conditions were calculated. Bypass roads of the city were characterized by a significantly greater length of sections with TTU compared to the city streets from Tuesday to Thursday and Sunday (p<0.05). The increased complication of traffic conditions during morning and evening rush hours led to an average annual increase in emissions of the main components of vehicle exhaust gases of 17.7% and 14.9% respectively, with the largest increase in emissions being typical for the city center. At the same time, the maximum complication of transport conditions on the bypass roads was observed in the summer and spring (from Monday to Wednesday and Sunday), while on city highways - on working days in the autumn and weekends in winter. On the city streets, the greatest length of heavy traffic conditions during the morning rush hour was observed in winter, and the shortest was in summer, while the evening rush hour, on the contrary, was most pronounced in autumn. On the bypass roads, there was a clear tendency towards heavier transport conditions over a longer period of the day according to the scheme winter–autumn–spring– summer.

scholarly journals Characteristics of Traffic Flows at Kuda Mati non-traffic light Intersection in Workhour and Holidays

2018 ◽  
Vol 73 ◽  
pp. 08030
Author(s):  
F. Betaubun Herbin
Keyword(s):  
Traffic Flow ◽  
Movement Pattern ◽  
Survey Method ◽  
Traffic Flows ◽  
Traffic Light ◽  
City Center ◽  
Work Time ◽  
Traffic Lights ◽  
Economic Support ◽  
The City

Characteristics of traffic flow needs to be revealed to describe the traffic flow that occurred at the research location. One of the patterns of traffic flow movement of Merauke Regency that is important enough to be observed is the movement pattern that occurs at Kuda Mati Non-traffic lights Intersection. This intersection is one of the access for economic support of Merauke Regency. The intersection connects the city center to the production centers and is used by the community to perform activities in meeting their needs such as working and meeting the needs of clothing, food and shelter. This fulfillment activity is usually differentiated according to work time and holiday time. The method used is survey method to describe the characteristics of traffic flow at the intersection. Data analysis applied MKJI 1997. The results show that peak hour traffic flow occurs at 17.00 - 18.00 on holiday 803 smp / hour, while for working time the traffic flow is evenly distributed with maximum vehicle volume occur at 12:00 to 13:00 which amounted to 471 smp / hour.

scholarly journals The Main Components of Vehicle Exhaust Gases and Their Effective Catalytic Neutralization

2019 ◽  
Vol 35 (1) ◽  
pp. 110-127 ◽  
Author(s):  
L. R. Sassykova ◽  
Y. A. Aubakirov ◽  
S. Sendilvelan ◽  
Zh. Kh. Tashmukhambetova ◽  
M. F. Faizullaeva ◽  
...  
Keyword(s):  
Combustible Mixture ◽  
Motor Vehicles ◽  
Toxic Substances ◽  
Vehicle Exhaust ◽  
Exhaust Gases ◽  
Gasoline Engines ◽  
Ceramic Block ◽  
Mode Of Operation ◽  
Main Components

The constantly increasing growth in the number of cars is one of the reasons for the deterioration of the ecological situation in cities and large settlements. In Kazakhstan, on a national scale, the share of motor vehicles in total emissions of pollutants into the atmosphere by all technogenic sources reaches on average 40%, in the mass of industrial waste - 2%. The content of toxic substances in the exhaust of diesel and gasoline engines varies and depends on the type of engine and mode of operation, as well as on the quality of the fuel, the composition of the combustible mixture in the engine cylinders, speed and driving conditions, ignition system and fuel control. The number of all toxic components in the exhaust gas exceeds the maximum permissible standards by tens and hundreds of times. One of the most reliable ways to reduce the toxicity of vehicle exhaust gases and remove harmful substances is the complete oxidation of exhaust components using catalytic compositions on metal or ceramic block carriers. The article accumulates data from the scientific literature about toxicity of different components of exhaust gases and catalytic neutralization of vehicle exhaust gases by various scientific schools.

scholarly journals Heavy traffic analysis of a transportation network model

1996 ◽  
Vol 33 (03) ◽  
pp. 870-885
Author(s):  
William P. Peterson ◽  
Lawrence M. Wein
Keyword(s):  
Queueing Networks ◽  
Transportation Network ◽  
Heavy Traffic ◽  
Queueing Network ◽  
Network Models ◽  
Reflected Brownian Motion ◽  
Traffic Conditions ◽  
Heavy Traffic Analysis ◽  
Functional Central Limit ◽  
Heavy Traffic Conditions

We study a model of a stochastic transportation system introduced by Crane. By adapting constructions of multidimensional reflected Brownian motion (RBM) that have since been developed for feedforward queueing networks, we generalize Crane's original functional central limit theorem results to a full vector setting, giving an explicit development for the case in which all terminals in the model experience heavy traffic conditions. We investigate product form conditions for the stationary distribution of our resulting RBM limit, and contrast our results for transportation networks with those for traditional queueing network models.

scholarly journals A unified method to analyze overtake free queueing systems

1996 ◽  
Vol 28 (2) ◽  
pp. 588-625 ◽  
Author(s):  
Dimitris Bertsimas ◽  
Georgia Mourtzinou
Keyword(s):  
Heavy Traffic ◽  
Complete Solution ◽  
Queueing Systems ◽  
Exact Results ◽  
Traffic Conditions ◽  
Special Cases ◽  
Number Of Customers ◽  
First In First Out ◽  
Heavy Traffic Conditions ◽  
Unified Method

In this paper we demonstrate that the distributional laws that relate the number of customers in the system (queue), L(Q) and the time a customer spends in the system (queue), S(W) under the first-in-first-out (FIFO) discipline are special cases of the H = λG law and lead to a complete solution for the distributions of L, Q, S, W for queueing systems which satisfy distributional laws for both L and Q (overtake free systems). Moreover, in such systems the derivation of the distributions of L, Q, S, W can be done in a unified way. Consequences of the distributional laws include a generalization of PASTA to queueing systems with arbitrary renewal arrivals under heavy traffic conditions, a generalization of the Pollaczek–Khinchine formula to the G//G/1 queue, an extension of the Fuhrmann and Cooper decomposition for queues with generalized vacations under mixed generalized Erlang renewal arrivals, approximate results for the distributions of L, S in a GI/G/∞ queue, and exact results for the distributions of L, Q, S, W in priority queues with mixed generalized Erlang renewal arrivals.

scholarly journals Weak Convergence Limits for Sojourn Times in Cyclic Queues Under Heavy Traffic Conditions

2008 ◽  
Vol 45 (2) ◽  
pp. 333-346 ◽  
Author(s):  
Hans Daduna ◽  
Christian Malchin ◽  
Ryszard Szekli
Keyword(s):  
Central Limit Theorem ◽  
Limit Theorem ◽  
Weak Convergence ◽  
Central Limit ◽  
Cycle Time ◽  
Heavy Traffic ◽  
Traffic Conditions ◽  
Sojourn Times ◽  
Population Sizes ◽  
Heavy Traffic Conditions

We consider sequences of closed cycles of exponential single-server nodes with a single bottleneck. We study the cycle time and the successive sojourn times of a customer when the population sizes go to infinity. Starting from old results on the mean cycle times under heavy traffic conditions, we prove a central limit theorem for the cycle time distribution. This result is then utilised to prove a weak convergence characteristic of the vector of a customer's successive sojourn times during a cycle for a sequence of networks with population sizes going to infinity. The limiting picture is a composition of a central limit theorem for the bottleneck node and an exponential limit for the unscaled sequences of sojourn times for the nonbottleneck nodes.

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