scholarly journals PECULIARITIES OF MONITORING FOR INFRASOUND POLLUTION OF RESIDENTIAL AREAS LOCATED IN PROXIMITY TO HIGHWAYS

2018 ◽  
Vol 97 (12) ◽  
pp. 1141-1145 ◽  
Author(s):  
Elena B. Kuznetsova ◽  
I. D. Bulavina
Keyword(s):  
Large Scale ◽  
Free Field ◽  
Experimental Studies ◽  
Measurement Data ◽  
Sound Field ◽  
Wind Load ◽  
Residential Areas ◽  
Noise Measurements ◽  
Research Findings ◽  
Determination Of Parameters

Introduction. Procedural provision of studies on monitoring for infrasound pollution of residential areas located in proximity to highways is the issue of the consideration in this article. The fact of the absence of a standardized procedure for carrying out large-scale studies of the infrasound range of the sound pressure in residential areas is reported. A brief review of regulatory documents currently used by experts of accredited laboratories, hygiene and epidemiology centers to solve sanitary problems of infrasound range acoustics, is given. Material and Methods. As a rule, experts use techniques for a hearing range of noise measurements and procedures specified by device service instructions which result in significant inconsistencies of research findings. Determination of parameters affecting the accuracy of research findings carried out with the help of routine devices available in hygiene and epidemiology centers was the objective of infrasound measurements presented here. Results. Effect of wind flows, study duration and monitoring location point were found to be the major parameters affecting the accuracy of research findings. Data on wind load on Saint-Petersburg territory is reported. Territories in the immediate proximity to the “West Speed Diameter” (WSD) highway, Ring motorway and Sinopskaya embankment being potential infrasound sources, were chosen for experimental studies. Such choice was caused by the heavy freight and passenger car traffic characterized by relatively permanent intensity. Discussion. Measurement series at various wind loads and of different durations were done. Measurement points were chosen in free field and in the vicinity of echoing areas. Measurement data were assessed taking into account expanded uncertainty, at 95% confidence level. It was found that reliable measurement results in infrasound frequency range can be obtained on the territory at wind velocity not exceeding 1 m/sec, during measurements in the free sound field with duration over 20 minutes. Given wind load conditions can be realized in St.-Petersburg for several days a month.

Investigation of ambient noise seismological methods on a bridge model

2021 ◽  
Author(s):  
Chun-Man Liao ◽  
Franziska Mehrkens ◽  
Celine Hadziioannou ◽  
Ernst Niederleithinger
Keyword(s):  
Wave Propagation ◽  
Large Scale ◽  
Seismic Velocity ◽  
Measurement Data ◽  
Correlation Coefficients ◽  
Coda Wave ◽  
Velocity Change ◽  
Promising Tool ◽  
Bridge Model ◽  
Noise Measurements

<p>The aim of this work is to investigate the application of seismological noise-based monitoring for bridge structures. A large-scale two-span concrete bridge model with a build-in post-tensioning system, which is exposed to environmental conditions, is chosen as our experimental test structure. Ambient seismic noise measurements were carried out under different pre-stressed conditions. Using the seismic interferometry technique, which is applied to the measurement data in the frequency domain, we reconstruct waveforms that relate to wave propagation in the structure. The coda wave interferometry technique is then implemented by comparing two waveforms recorded in two pre-stress states. Any relative seismic velocity changes are identified by determining the correlation coefficients and reveal the influence of the pre-stressing force. The decrease of the wave propagation velocity indicates the loss of the pre-stress and weakening stiffness due to opening or event extension of cracks. We conclude that the seismological methods used to estimate velocity change can be a promising tool for structural health monitoring of civil structures.</p>

Geoecological assessment of acoustic screens using for protection residential areas when transportation minerals by rail

2017 ◽  
pp. 36-43
Author(s):  
Olga Kopytenkova ◽  
Dmitriy Kurepin ◽  
Ekaterina Vereshchagina
Keyword(s):  
Practical Importance ◽  
Reference Conditions ◽  
Measurement Data ◽  
Excess Noise ◽  
Normative Values ◽  
Residential Areas ◽  
Acoustic Environment ◽  
Allowable Level ◽  
Noise Measurements ◽  
Standard Values

Objective: Аssessment of acoustic screens effectiveness for protection residential areas when transportation minerals by rail. Methods: The experiment, simulation of acoustic environment. Results: Оne of the main problems of big cities is protection of population from excessive noise. To assess the acoustic screens effectiveness for protection residential areas when transportation minerals by rail were carried out noise measurements at the station Pontoon. The obtained measurement data show that the excess noise above the standard values. Therefore, to reduce noise it is necessary to conduct anti-noise measures. One of the most common means of reducing the noise of rail transport, is the use of acoustic screens. In the work carried out simulation of an acoustic screen using the program «Acoustics» at the following reference conditions: acoustic screen with a height of 5 m were installed on the site along houses № 13–16, 18, 19 A. Titenko Str (railway station Pontoon); design points were taken at a distance of not less than 1 m from the facade of buildings. The obtained simulation results show that normative values are reached only at the height of the calculation points is up to 5 m. With increasing elevation there is growing noise beyond the maximum permissible level. Research shows that the acoustic screen would be effective only at the level of 1–2 floors of the building. Low screen efficiency with increasing altitude is due to the missing in the sound area of the shadow calculated points located above 5 m. Practical importance: Revision of existing noise regulations of the railway transport in the direction of increasing the maximum allowable level by using amendments, can reduce complaints of noise from rail freight transport (in particular carrying solid minerals).

Geomechanical behavior of jointed rock mass in the large-scale blast impact zone

2020 ◽  
pp. 11-14
Author(s):  
V. N. Tyupin ◽  
Keyword(s):  
Rock Mass ◽  
Large Scale ◽  
Measurement Data ◽  
Ground Surface ◽  
Jointed Rock ◽  
Jointed Rock Mass ◽  
Open Pit ◽  
Velocity Versus ◽  
Research Findings ◽  
Seismic Impact

The review of literature sources has allowed determining the mechanism of seismic blasts waves in jointed rock mass. The author presents the theoretical formulas for calculating stresses, relative strains and displacement velocities induced in rock mass by large-scale blasts. The formulas take into account the detonation characteristics of explosives, the borehole diameter, the length of explosive charges, the number of simultaneously blasted charges per groups and the factor of explosion energy redistribution to rock throw. Moreover, the formulas include the properties of rocks between the blasting point and a guarded object, and on the exposed surface of a guarded object. The compressive stresses, relative strains and displacement velocities in rocks are calculated from the formulas. The theoretically found change in the displacement velocity versus distance agrees with the field measurement data obtained in an open pit mine of Polyus company. The formulas of stresses and relative strains were used to define seismic impact exerted by large-scale blasts on the barrier of dry dock No. 1. Based on the calculated results, the recommendations are developed on reduction of seismic impact of blasts during dredging in the dock. The research findings are applicable to developing blasting regulations toward reduction in seismic impact of large-scale explosions on exposed surfaces in rock mass, as well as on the ground surface structures and buildings.

Methods of Network Planning and Management when Implementing Territory Planning Projects

2019 ◽  
pp. 49-54
Keyword(s):  
Large Scale ◽  
Housing Stock ◽  
Network Planning ◽  
Network Models ◽  
Point Of View ◽  
Residential Areas ◽  
Basic Principles ◽  
Planning And Management ◽  
Planning Project ◽  
Complex Process

The success of the Program of housing stock renovation in Moscow depends on the efficiency of resource management. One of the main urban planning documents that determine the nature of the reorganization of residential areas included in the Program of renovation is the territory planning project. The implementation of the planning project is a complex process that has a time point of its beginning and end, and also includes a set of interdependent parallel-sequential activities. From an organizational point of view, it is convenient to use network planning and management methods for project implementation. These methods are based on the construction of network models, including its varieties – a Gantt chart. A special application has been developed to simulate the implementation of planning projects. The article describes the basic principles and elements of modeling. The list of the main implementation parameters of the Program of renovation obtained with the help of the developed software for modeling is presented. The variants of using the results obtained for a comprehensive analysis of the implementation of large-scale urban projects are proposed.

Soil/Tire Interaction Analysis Using FEM and FVM

2005 ◽  
Vol 33 (1) ◽  
pp. 38-62 ◽  
Author(s):  
S. Oida ◽  
E. Seta ◽  
H. Heguri ◽  
K. Kato
Keyword(s):  
Large Scale ◽  
Interaction Analysis ◽  
Yield Criterion ◽  
Surrounding Medium ◽  
Flow Analysis ◽  
Measurement Data ◽  
Traction Force ◽  
Elastoplastic Material ◽  
The Road ◽  
Soil Flow

Abstract Vehicles, such as an agricultural tractor, construction vehicle, mobile machinery, and 4-wheel drive vehicle, are often operated on unpaved ground. In many cases, the ground is deformable; therefore, the deformation should be taken into consideration in order to assess the off-the-road performance of a tire. Recent progress in computational mechanics enabled us to simulate the large scale coupling problem, in which the deformation of tire structure and of surrounding medium can be interactively considered. Using this technology, hydroplaning phenomena and tire traction on snow have been predicted. In this paper, the simulation methodology of tire/soil coupling problems is developed for pneumatic tires of arbitrary tread patterns. The Finite Element Method (FEM) and the Finite Volume Method (FVM) are used for structural and for soil-flow analysis, respectively. The soil is modeled as an elastoplastic material with a specified yield criterion and a nonlinear elasticity. The material constants are referred to measurement data, so that the cone penetration resistance and the shear resistance are represented. Finally, the traction force of the tire in a cultivated field is predicted, and a good correlation with experiments is obtained.

scholarly journals Leisure Time Sports Activities and Life Satisfaction: Deeper Insights Based on a Representative Survey from Germany

2020 ◽  
Author(s):  
Michael Mutz ◽  
Anne K. Reimers ◽  
Yolanda Demetriou
Keyword(s):  
Life Satisfaction ◽  
Large Scale ◽  
Leisure Time ◽  
Organizational Context ◽  
Experimental Studies ◽  
Well Being ◽  
Activity Level ◽  
Leisure Satisfaction ◽  
General Life Satisfaction ◽  
Sports Activities

Abstract Observational and experimental studies show that leisure time sporting activity (LTSA) is associated with higher well-being. However, scholars often seem to assume that 1) LTSA fosters “general” life satisfaction, thereby ignoring effects on domain satisfaction; 2) the effect of LTSA on well-being is linear and independent of a person’s general activity level; 3) the amount of LTSA is more important than the repertoire of LTSA, i.e. the number of different activities; 4) all kinds of LTSA are equal in their effects, irrespective of spatial and organisational context conditions. Using data from the German SALLSA-Study (“Sport, Active Lifestyle and Life Satisfaction”), a large-scale CAWI-Survey (N = 1008) representing the population ≥ 14 years, the paper takes a closer look on these assumptions. Findings demonstrate that LTSA is associated with general life satisfaction and domain-specific satisfaction (concerning relationships, appearance, leisure, work and health), but that the relationship is most pronounced for leisure satisfaction. Associations of sport with life satisfaction, leisure satisfaction and subjective health are non-linear, approaching an injection point from which on additional LTSA is no longer beneficial. Moreover, findings lend support to the notion that diversity in LTSA matters, as individuals with higher variation in sports activities are more satisfied. Finally, results with regard to spatial and organizational context suggest that outdoor sports and club-organized sports have additional benefits.

scholarly journals Inverse Infiltration Modeling of Dike Covers Made of Dredged Material Using PEST and AMALGAM

Geosciences ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 41
Author(s):  
Tim Jurisch ◽  
Stefan Cantré ◽  
Fokke Saathoff
Keyword(s):  
Large Scale ◽  
Measurement Data ◽  
Fine Grained ◽  
Dredged Materials ◽  
Measurement Results ◽  
Large Scale Field ◽  
Eigenvalue Ratio ◽  
Ill Posed ◽  
Materials Used ◽  
Installation Technology

A variety of studies recently proved the applicability of different dried, fine-grained dredged materials as replacement material for erosion-resistant sea dike covers. In Rostock, Germany, a large-scale field experiment was conducted, in which different dredged materials were tested with regard to installation technology, stability, turf development, infiltration, and erosion resistance. The infiltration experiments to study the development of a seepage line in the dike body showed unexpected measurement results. Due to the high complexity of the problem, standard geo-hydraulic models proved to be unable to analyze these results. Therefore, different methods of inverse infiltration modeling were applied, such as the parameter estimation tool (PEST) and the AMALGAM algorithm. In the paper, the two approaches are compared and discussed. A sensitivity analysis proved the presumption of a non-linear model behavior for the infiltration problem and the Eigenvalue ratio indicates that the dike infiltration is an ill-posed problem. Although this complicates the inverse modeling (e.g., termination in local minima), parameter sets close to an optimum were found with both the PEST and the AMALGAM algorithms. Together with the field measurement data, this information supports the rating of the effective material properties of the applied dredged materials used as dike cover material.

scholarly journals Why does the spread of COVID-19 vary greatly in different countries? Revealing the efficacy of face masks in epidemic prevention

2021 ◽  
Vol 149 ◽  
Author(s):  
Jincheng Wei ◽  
Shurui Guo ◽  
Enshen Long ◽  
Li Zhang ◽  
Bizhen Shu ◽  
...  
Keyword(s):  
Social Isolation ◽  
Large Scale ◽  
Experimental Studies ◽  
Weighted Average ◽  
Filtration Efficiency ◽  
Volume Distribution ◽  
Particle Sizes ◽  
Economic Activities ◽  
Protection Measure ◽  
Source Of Infection

Abstract The severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) is highly contagious, and the coronavirus disease 2019 (COVID-19) pandemic caused by it has forced many countries to adopt ‘lockdown’ measures to prevent the spread of the epidemic through social isolation of citizens. Some countries proposed universal mask wearing as a protection measure of public health to strengthen national prevention efforts and to limit the wider spread of the epidemic. In order to reveal the epidemic prevention efficacy of masks, this paper systematically evaluates the experimental studies of various masks and filter materials, summarises the general characteristics of the filtration efficiency of isolation masks with particle size, and reveals the actual efficacy of masks by combining the volume distribution characteristics of human exhaled droplets with different particle sizes and the SARS-CoV-2 virus load of nasopharynx and throat swabs from patients. The existing measured data show that the filtration efficiency of all kinds of masks for large particles and extra-large droplets is close to 100%. From the perspective of filtering the total number of pathogens discharged in the environment and protecting vulnerable individuals from breathing live viruses, the mask has a higher protective effect. If considering the weighted average filtration efficiency with different particle sizes, the filtration efficiencies of the N95 mask and the ordinary mask are 99.4% and 98.5%, respectively. The mask can avoid releasing active viruses to the environment from the source of infection, thus maximising the protection of vulnerable individuals by reducing the probability of inhaling a virus. Therefore, if the whole society strictly implements the policy of publicly wearing masks, the risk of large-scale spread of the epidemic can be greatly reduced. Compared with the overall cost of social isolation, limited personal freedoms and forced suspension of economic activities, the inconvenience for citizens caused by wearing masks is perfectly acceptable.

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