scholarly journals Effect of Different Structure Type Traffic On Railway Line Capacity

2017 ◽  
Vol 24 (s1) ◽  
pp. 82-88 ◽  
Author(s):  
Radosław Gleba ◽  
Sławomir Grulkowski ◽  
Jerzy Zariczny
Keyword(s):  
Structure Type ◽  
Type Structure ◽  
Railway Line ◽  
Railway Traffic ◽  
Traffic Conditions ◽  
Two Parameters ◽  
The Impact

AbstractThe article points to methods of analyzing railway traffic conditions based on two parameters: capacity and delay of trains. The impact of the differentiated railway type structure on the capacity of the railway line was presented. Particular attention has been paid to the assessment of commonly used simplifications in analyzes.

scholarly journals Tin and Antimony As Soil Pollutants Along The Railway Lines

2021 ◽  
Author(s):  
Zvjezdana Stančić ◽  
Željka Fiket ◽  
Andreja Vuger
Keyword(s):  
Data Analysis ◽  
Total Mass ◽  
Humus Content ◽  
Railway Line ◽  
Railway Traffic ◽  
Natural Factors ◽  
Exhaust Fumes ◽  
Mass Fractions ◽  
Excessive Entry ◽  
The Impact

Abstract Antimony (Sb) and tin (Sn) in soils along railway lines pose a serious environmental risk. The study, conducted at 60 sites along the 160 km railway line connecting the Croatian capital Zagreb with surrounding smaller settlements and towns, showed pronounced soil Sb and Sn enrichment up to 87 and 33 times the median for European soils, respectively. The total mass fractions of Sb ranged from 0.98 to 52.0 mg/kg and of Sn from 3.04 mg/kg to 97.6 mg/kg. The origin of the enrichment is railway traffic, but precise sources are difficult to define, however available literature points to abrasion from brakes, rails, wheels and overhead wires, exhaust fumes from locomotive engines and cargo waste as predominant sources. The comprehensive data analysis suggested that the Sb and Sn distribution in soils near railway lines was not only conditioned by natural factors such as soil texture, humus content and soil pH, but also by the distance to the tracks, which is not necessarily linear, the site functionality, the topography and the age of the railway line. Observed soil contamination with antimony and tin requires further research to increase knowledge of the impact of railways on Sb and Sn soil content, and to establish safety distances that will ensure the least possible impact of rail traffic on nearby crops and prevent their excessive entry into the food chain.

scholarly journals Impact of Scene Content on High Resolution Video Quality

Sensors ◽  
2021 ◽  
Vol 21 (8) ◽  
pp. 2872
Author(s):  
Miroslav Uhrina ◽  
Anna Holesova ◽  
Juraj Bienik ◽  
Lukas Sevcik
Keyword(s):  
Video Compression ◽  
Spatial Information ◽  
Video Quality ◽  
Video Sequences ◽  
Compression Efficiency ◽  
Opinion Score ◽  
Scene Description ◽  
Two Parameters ◽  
The University ◽  
The Impact

This paper deals with the impact of content on the perceived video quality evaluated using the subjective Absolute Category Rating (ACR) method. The assessment was conducted on eight types of video sequences with diverse content obtained from the SJTU dataset. The sequences were encoded at 5 different constant bitrates in two widely video compression standards H.264/AVC and H.265/HEVC at Full HD and Ultra HD resolutions, which means 160 annotated video sequences were created. The length of Group of Pictures (GOP) was set to half the framerate value, as is typical for video intended for transmission over a noisy communication channel. The evaluation was performed in two laboratories: one situated at the University of Zilina, and the second at the VSB—Technical University in Ostrava. The results acquired in both laboratories reached/showed a high correlation. Notwithstanding the fact that the sequences with low Spatial Information (SI) and Temporal Information (TI) values reached better Mean Opinion Score (MOS) score than the sequences with higher SI and TI values, these two parameters are not sufficient for scene description, and this domain should be the subject of further research. The evaluation results led us to the conclusion that it is unnecessary to use the H.265/HEVC codec for compression of Full HD sequences and the compression efficiency of the H.265 codec by the Ultra HD resolution reaches the compression efficiency of both codecs by the Full HD resolution. This paper also includes the recommendations for minimum bitrate thresholds at which the video sequences at both resolutions retain good and fair subjectively perceived quality.

Strukturvarianten des MgCu2-Typs: Die Verbindungen Mg2Ni3P und Mg2Ni3As / Variants of the MgCu2 Type: The Compounds Mg2Ni3P and Mg2Ni3As

1992 ◽  
Vol 47 (10) ◽  
pp. 1351-1354 ◽  
Author(s):  
Viktor Keimes ◽  
Albrecht Mewis
Keyword(s):  
Single Crystal ◽  
Homogeneity Range ◽  
Hexagonal Lattice ◽  
Structure Type ◽  
Type Structure ◽  
X Ray ◽  
Lattice Constants ◽  
Metal Atoms ◽  
Rhombohedral Symmetry

The compounds Mg2Ni3P and Mg2Ni3As were prepared by heating the elements. Their structures have been determined from single-crystal X-ray data. The structure of the phosphide is a rhombohedral ternary variant of the cubic Laves structure type MgCu2 (R 3̄ m; hexagonal lattice constants: a = 4.971(0) Å, c = 10.961(2) Å). The ordered substitution of one quarter of the metal atoms by phosphorus and the resulting shorter distances are responsible for the rhombohedral symmetry.The arsenide crystallizes in the MgCu2 type structure (Fd 3 m; a = 6.891(1)A, composition Mg2Ni3As) with a statistic distribution of the Ni and As atoms; the relevant homogeneity range extends from Mg2Ni2.9As1.1 to Mg2Ni3.5As0.5.

scholarly journals Coastal Mangrove Response to Marine Erosion: Evaluating the Impacts of Spatial Distribution and Vegetation Growth in Bangkok Bay from 1987 to 2017

2020 ◽  
Vol 12 (2) ◽  
pp. 220 ◽  
Author(s):  
Han Xiao ◽  
Fenzhen Su ◽  
Dongjie Fu ◽  
Qi Wang ◽  
Chong Huang
Keyword(s):  
Spatial Distribution ◽  
Vegetation Index ◽  
Normalized Difference Vegetation Index ◽  
Mangrove Ecosystem ◽  
Early Growth ◽  
Growth Stages ◽  
Human Disturbances ◽  
Vegetation Growth ◽  
Two Parameters ◽  
The Impact

Long time-series monitoring of mangroves to marine erosion in the Bay of Bangkok, using Landsat data from 1987 to 2017, shows responses including landward retreat and seaward extension. Quantitative assessment of these responses with respect to spatial distribution and vegetation growth shows differing relationships depending on mangrove growth stage. Using transects perpendicular to the shoreline, we calculated the cross-shore mangrove extent (width) to represent spatial distribution, and the normalized difference vegetation index (NDVI) was used to represent vegetation growth. Correlations were then compared between mangrove seaside changes and the two parameters—mangrove width and NDVI—at yearly and 10-year scales. Both spatial distribution and vegetation growth display positive impacts on mangrove ecosystem stability: At early growth stages, mangrove stability is positively related to spatial distribution, whereas at mature growth the impact of vegetation growth is greater. Thus, we conclude that at early growth stages, planting width and area are more critical for stability, whereas for mature mangroves, management activities should focus on sustaining vegetation health and density. This study provides new rapid insights into monitoring and managing mangroves, based on analyses of parameters from historical satellite-derived information, which succinctly capture the net effect of complex environmental and human disturbances.

Approach to Quantify the Impact of Disruptions on Traffic Conditions using Dynamic Weighted Resilience Metrics of Transport Networks

2021 ◽  
pp. 036119812199866 ◽  
Author(s):  
Elise Henry ◽  
Angelo Furno ◽  
Nour-Eddin El Faouzi
Keyword(s):  
Three Dimensional ◽  
Traffic Load ◽  
Transport Networks ◽  
Traffic Conditions ◽  
Probe Vehicle ◽  
Vehicle Data ◽  
Network Operations ◽  
Network States ◽  
The Impact ◽  
Proper Operation

Transport networks are essential for societies. Their proper operation has to be preserved to face any perturbation or disruption. It is therefore of paramount importance that the modeling and quantification of the resilience of such networks are addressed to ensure an acceptable level of service even in the presence of disruptions. The paper aims at characterizing network resilience through weighted degree centrality. To do so, a real dataset issued from probe vehicle data is used to weight the graph by the traffic load. In particular, a set of disrupted situations retrieved from the study dataset is analyzed to quantify the impact on network operations. Results demonstrate the ability of the proposed metrics to capture traffic dynamics as well as their utility for quantifying the resilience of the network. The proposed methodology combines different metrics from the complex networks theory (i.e., heterogeneity, density, and symmetry) computed on temporal and weighted graphs. Time-varying traffic conditions and disruptions are analyzed by providing relevant insights on the network states via three-dimensional maps.

scholarly journals Analysis of Errors in the Estimation of Impact Positions in Plate-Like Structure through the Triangulation Formula by Piezoelectric Sensors Monitoring

Sensors ◽  
2018 ◽  
Vol 18 (10) ◽  
pp. 3426 ◽  
Author(s):  
Eugenio Marino-Merlo ◽  
Andrea Bulletti ◽  
Pietro Giannelli ◽  
Marco Calzolai ◽  
Lorenzo Capineri
Keyword(s):  
Propagation Velocity ◽  
Lamb Waves ◽  
Correlation Method ◽  
Time Of Arrival ◽  
Impact Point ◽  
Laboratory Procedure ◽  
Impact Position ◽  
Set Up ◽  
Two Parameters ◽  
The Impact

The structural health monitoring (SHM) of critical structures is a complex task that involves the use of different sensors that are also aimed at the identification of the location of the impact point using ultrasonic sensors. For the evaluation of the impact position, reference is often made to the well-known triangulation method. This method requires the estimation of the differential time of arrival (DToA) and the group velocity of the Lamb waves propagating into a plate-like structure: the uncertainty of these two parameters is taken into consideration as main cause of localization error. The work proposes a simple laboratory procedure based on a set-up with a pair of sensors that are symmetrically placed with respect to the impact point, to estimate the uncertainty of the DToA and the propagation velocity estimates. According to a theoretical analysis of the error for the impact position, the experimental uncertainties of DToA and the propagation velocity are used to estimate the overall limit of the SHM system for the impact positioning. Because the error for the DToA estimate depends also on the adopted signal processing, three common methods are selected and compared: the threshold, the correlation method, and a likelihood algorithm. Finally, the analysis of the positioning error using multisensory configuration is reported as useful for the design of the SHM system.

Parameter Study of Concrete Impact Damage Model Based on DOE Analysis

2012 ◽  
Vol 502 ◽  
pp. 451-457
Author(s):  
Jiang Bo Wang ◽  
Qing Ming Zhang ◽  
Cheng Liang Feng ◽  
Wei Bing Li ◽  
Heng Wang
Keyword(s):  
Impact Velocity ◽  
Impact Damage ◽  
Damage Model ◽  
Considerable Effect ◽  
Model Material ◽  
Parameter Study ◽  
Material Parameters ◽  
Model Based ◽  
Two Parameters ◽  
The Impact

By building up a debugging method about material parameters of concrete impact damage model based on DOE (Design of Experiments) analysis, this paper studies the influence of material parameters of concrete targets on the results of numerical simulation based on quantitative analysis, when the impact velocity is 300m/s and 850m/s respectively. It concludes that when the impact velocity of 300m/s, 5 parameters have considerable effect on the residual velocity of warhead, they are ， ， ， and . Of all 5 parameters, , and can be obtained by calculation therefore it only needs to debug two parameters and according to experiments. Finally, when the impact velocity is 300m/s or so, debug combining the experiments to get a set of concrete impact damage model material parameters to make the results of simulation and experiment anastomosis well.

Impact of N-Shaped Wing Morphing on Solar-Powered Aircraft

2020 ◽  
pp. 1-12
Author(s):  
Mostafa E. El-Salamony ◽  
Mohamed A. Aziz
Keyword(s):  
Solar Energy ◽  
Lift Coefficient ◽  
Morphing Wing ◽  
Aerial Vehicles ◽  
Aircraft Performance ◽  
Aerial Vehicle ◽  
Solar Powered ◽  
Two Parameters ◽  
Wing Morphing ◽  
The Impact

Generally, unmanned aerial vehicles and micro aerial vehicles depend on batteries or conventional fuel as a source of energy. These sources of energy have limited flight time, relatively high cost, and also a certain level of pollutants. Solar energy applied to aerial vehicles is an excellent alternative way to overcome other sources of energy’s disadvantage. This study aimed to design a solar-powered aerial vehicle to achieve continuous flight on Earth. The efficiency of the solar system is related to the absorbed sun rays. The concept of an anti-symmetric N-shaped morphing wing is a good idea to increase the collected solar energy during the daily sun path. But this comes with the penalty of side forces and moments due to the anti-symmetry of the wing. This paper introduces a study for two parameters that strongly affect the aerodynamics of the N-shaped morphing wing; the dihedral part angle and the dihedral part length. The impact of the dihedral angle decreases the lift coefficient and increases the drag coefficient. The impact of the morphing wing on the aircraft performance is also considered.

Low Velocity Impact on Fiber Reinforced Geocomposites

2016 ◽  
Vol 827 ◽  
pp. 145-148 ◽  
Author(s):  
Sneha Samal ◽  
David Reichmann ◽  
Iva Petrikova ◽  
Bohdana Marvalova
Keyword(s):  
Impact Damage ◽  
Acoustic Vibration ◽  
Low Velocity Impact ◽  
Low Velocity ◽  
Velocity Impact ◽  
Impact Behaviour ◽  
Reinforced Composite ◽  
Before And After ◽  
Two Parameters ◽  
The Impact

Low velocity impact strength of the fabric reinforced geocomposite has investigated in this article. Various fabrics such as carbon and E-glass were considered for reinforcement in geopolymer matrix. The primary two parameters such as low velocity, impact damage modes are explained on the E-glass and carbon based fabric geocomposite. The onset mode of damage to failure mode is examined through C-scan analysis. The quality of the composite is observed using c-scan with acoustic vibration mode of sensor before and after impact test. Then the effect of fabric and matrix on the impact behaviour is discussed. Residual strength of the composite is measured to determine post impact behaviour. It has been observed that resistance properties of E-glass reinforced composite is better than carbon fabric reinforced composite.

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