scholarly journals Near-Field Measurement of Six Degrees of Freedom Mining-Induced Tremors in Lower Silesian Copper Basin

Sensors ◽  
2020 ◽  
Vol 20 (23) ◽  
pp. 6801
Author(s):  
Krzysztof Fuławka ◽  
Witold Pytel ◽  
Bogumiła Pałac-Walko
Keyword(s):  
Seismic Wave ◽  
Degrees Of Freedom ◽  
Seismic Waves ◽  
Near Field ◽  
High Energy ◽  
Rotational Component ◽  
Empirical Formulas ◽  
Six Degrees Of Freedom ◽  
The Impact

The impact of seismicity on structures is one of the key problems of civil engineering. According to recent knowledge, the reliable analysis should be based on both rotational and translational components of the seismic wave. To determine the six degrees of freedom (6-DoF) characteristic of mining-induced seismicity, two sets of seismic posts were installed in the Lower Silesian Copper Basin, Poland. Long-term continuous 6-DoF measurements were conducted with the use of the R-1 rotational seismometer and EP-300 translational seismometer. In result data collection, the waveforms generated by 39 high-energy seismic events were recorded. The characteristic of the rotational component of the seismic waves were described in terms of their amplitude and frequency characteristics and were compared with translational measurements. The analysis indicated that the characteristic of the rotational component of the seismic wave differs significantly in comparison to translational ones, both in terms of their amplitude and frequency distribution. Also, attenuation of rotational and translational components was qualitatively compared. Finally, the empirical formulas for seismic rotation prediction in the Lower Silesian Copper Basin were developed and validated.

The Drugs and Natural Antioxidants as the Components of Anti-radiation Countermeasures during Cosmic Flights

2017 ◽  
pp. 66-73 ◽  
Author(s):  
И. Ушаков ◽  
I. Ushakov ◽  
М. Васин ◽  
M. Vasin
Keyword(s):  
Solar Activity ◽  
Cosmic Rays ◽  
Radiation Effects ◽  
High Energy ◽  
Galactic Cosmic Rays ◽  
Stress Factors ◽  
Solar Cosmic Rays ◽  
Post Radiation ◽  
The Impact

Radiation situation for cosmonauts over long-term cosmic flights is caused by low-rate radiation of galactic cosmic rays and solar cosmic rays consisting of high-energy proton as well as heavy particles (Z>10) within 1-2 % that is exclusively a threat of stochastic radiation effects (small increase of cancer risk and decrease of mean life span) for men. During interplanetary expedition periods the small probability of raised solar activity there is a threat of exposure to astronauts at doses that cause deterministic radiation effects leading to the development of the disease as a clinical manifestation of radiation injuries,. In a similar scenario it is necessary to have available to cosmic ship anti-radiation countermeasures for cosmonaut protection. Among radioprotective equipment can be provided with radiation protective agents and partial shielding of body separate section providing the best condition for post-radiation repair of radiosensitive body tissues. Preparation B-190 (indralin) is the most perspective from a small numbers of other radioprotectors permitting for men administration. Besides high radioprotective efficacy and large broadness of protective action B-190 is well tolerated including the impact of extrem flight factors. Antiemetic agent latran (ondansetron) is most interesting among preparation for prophylaxis and reduction of prodromal radiation reaction. To accelerate post-radiation hematopoietic recovery after raised solar activity an administration of radiomitigators (riboxin et al.) is substantiated. Neupomax (neupogen) is recommended as a preparation for pathogenesis therapy of acute radiation syndrome. Possible consequences of long-term cosmic voyages for oxidative stress development are taken into consideration. On their basis of nNatural antioxidants, preparations and nutrients radiomodulators, fully qualitative nutrition including vegetable food enriched flavonoids, vitamins C, E and carotene potentially prevent a shorten of cosmonaut biological age induced by solar cosmic rays and galactic cosmic rays and stress factors of long-term cosmic voyages. Radiomodulators are low and non-toxic and have not side effects in recommended doses. Their radioprotective effect is directly induced by adaption reaction on cellular and organismic levels through gene expression modulation and in that way the increase of non-specific body tolerance. The implementation of radiomodulator action is possible through hormesis mechanism.

scholarly journals The long-term effects of space weather on satellite operations

2010 ◽  
Vol 28 (6) ◽  
pp. 1361-1367 ◽  
Author(s):  
D. T. Welling
Keyword(s):  
Background Radiation ◽  
High Energy ◽  
High Energy Particle ◽  
Solar Cycles ◽  
Long Term Effects ◽  
Radiation Background ◽  
Particle Exposure ◽  
Total Lifetime ◽  
The Impact

Abstract. Integrated lifetime radiation damage may cause spacecraft to become more susceptible to operational anomalies by changing material characteristics of electronic components. This study demonstrates and quantifies the impact of these effects by examining the National Oceanic and Atmospheric Administration (NOAA) National Geophysical Data Center (NGDC) satellite anomaly database. Energetic particle data from the Geostationary Operational Environmental Satellites (GOES) is used to construct the total lifetime particle exposure a satellite has received at the epoch of an anomaly. These values are compared to the satellite's chronological age and the average exposure per year (calculated over two solar cycles.) The results show that many anomalies occur on satellites that have received a total lifetime high-energy particle exposure that is disproportionate to their age. In particular, 10.8% of all events occurred on satellites that received over two times more 20 to 40 MeV proton lifetime particle exposure than predicted using an average annual mean. This number inflates to 35.2% for 40 to 80 MeV protons and 33.7% for ≥2 MeV electrons. Overall, 73.5% of all anomalies occurred on a spacecraft that had experienced greater than two times the expected particle exposure for one of the eight particle populations used in this study. Simplistically, this means that the long term radiation background exposure matters, and that if the background radiation is elevated during the satellite's lifetime, the satellite is likely to experience more anomalies than satellites that have not been exposed to the elevated environment.

The Potential Impact of Oil and Other Non-Aqueous Phase Liquids (NAPLs) on the Long-Term Management of Radioactive Wastes

2003 ◽  
Author(s):  
M. M. Askarieh ◽  
A. W. Harris ◽  
S. J. Wisbey
Keyword(s):  
Waste Management ◽  
Aqueous Phase ◽  
Organic Materials ◽  
Near Field ◽  
Radioactive Wastes ◽  
Assessment Tools ◽  
The United Kingdom ◽  
The Impact ◽  
Term Management

The presence of non-aqueous phase liquids (NAPLs) in radioactive wastes has the potential to adversely affect their long-term management. The buoyancy of light NAPLs can represent a separate pathway for their migration from a waste management facility, such as a deep repository, to the accessible environment. Their inherent toxicity and potential burden of radionuclides need to be addressed. Nirex is currently developing an understanding of the behaviour of NAPLs and exploring the means of mitigating any adverse impact. NAPLs such as oils and solvents are present in existing wastes, but NAPLs can also be generated by degradation of some solid organic materials, such as plastics. Wastes arising in the United Kingdom that may contain NAPLs include liquids and sludges contaminated with oils, and waste items containing trapped oil, for example gearboxes and pumps. The reference inventory being assessed by Nirex also contains significant quantities of organic materials which can be considered to be potential precursors to the generation of NAPLs. A programme of work has been instigated by Nirex to develop a better understanding of the behaviour of NAPLs. The programme includes the following aspects: understanding the mechanisms by which NAPLs might be produced and existing NAPLs degraded and destroyed: • consideration of the containment that could be offered by packaging of wastes containing NAPLs; • investigating the extent to which radionuclides may be entrained in NAPLs; • understanding the migration of NAPLs in the near-field and in geological systems; • the impact of NAPLs on the surface properties of repository backfill and the geosphere; • development of assessment tools to quantify the potential risk due to NAPLs. This paper will describe the scope of this programme of work, and will provide examples from the ongoing programme to demonstrate that suitable long-term waste management solutions can be developed for NAPL containing wastes.

Numerical Simulation of Ship-Ship Interactions in Waves

2019 ◽  
Author(s):  
Xueshen Xie ◽  
Yuxiang Wan ◽  
Qing Wang ◽  
Hao Liu ◽  
Dakui Feng
Keyword(s):  
Numerical Simulation ◽  
Degrees Of Freedom ◽  
Simulation Analysis ◽  
Turbulence Models ◽  
Body Motion ◽  
Structured Grid ◽  
Six Degrees Of Freedom ◽  
Unsteady Rans ◽  
Small Ship ◽  
The Impact

Abstract A numerical simulation of the hydrodynamic interaction and attitude of a ship and two ships of different sizes navigating in parallel in waves were carried out in this paper. The study of the two ships navigating in parallel is of great significance in marine replenishment. This paper used in house computational fluid dynamics (CFD) code to solve unsteady RANS equation coupled with six degrees of freedom (6DOF) solid body motion equations. URANS equations are solved by finite difference method and PISO algorithm. Structured grid with overset technology have been used to make computations. Turbulence models used the Shear Stress Transport (SST) k-ω model. The method used for free surface simulation is single phase level set. In this paper, two DTMB 5415 with different scales are selected for simulation analysis. This paper analyzed the impact of the big ship on the small ship when the two ships were navigating in parallel. This paper also analyzed the relationship between interaction and velocity between hulls, which has certain guiding significance for the ship’s encounter on the sea.

General Observations of the Time-Dependent Flow Field Around Flat Plates in Free Fall

2015 ◽  
Author(s):  
Jakob Hærvig ◽  
Anna Lyhne Jensen ◽  
Marie Cecilie Pedersen ◽  
Henrik Sørensen
Keyword(s):  
Degrees Of Freedom ◽  
Model Development ◽  
Digital Camera ◽  
Free Fall ◽  
Flat Plates ◽  
Time Step ◽  
Future Studies ◽  
Six Degrees Of Freedom ◽  
Dependent Flow

The free fall trajectories of flat plates are investigated in order to improve understanding of the forces acting on falling blunt objects. The long term goal is to develop a general applicable model to predict free fall trajectories. Numerically the free fall of a flat plate is investigated using a six degrees of freedom (6DOF) solver and a dynamic mesh. To validate the simulation, the trajectories of aluminium plates falling in water are recorded by digital camera recordings and compared to the simulation. The simulation is able to calculate the motion of the plate within each time step with high accuracy, and thereby allowing the whole trajectory to be predicted with fair accuracy. With the numerical model able to predict the free fall and the complex plate fluid interactions, fluids forces can be extracted for model development in future studies.

A Seismic Wave Oblique Incidence Method and the Application in Gravity DAM Seismic Research

2014 ◽  
Vol 08 (04) ◽  
pp. 1450011 ◽  
Author(s):  
Li Chen ◽  
Liaojun Zhang
Keyword(s):  
Seismic Wave ◽  
Oblique Incidence ◽  
Large Scale ◽  
Seismic Waves ◽  
Seismic Analysis ◽  
Near Field ◽  
P Wave ◽  
Gravity Dam ◽  
Uniform Motion ◽  
Element Analysis

The incidence of seismic wave is generally assumed to be vertical in seismic analysis of large-scale hydraulic structures, but during some near-field earthquakes, the direction of seismic waves is at certain angle to the ground. The non-uniform motion produced by oblique incidence can significantly affect the structures. In this paper, based on the theories of wave motion an oblique P-wave and SV-wave incidence method based on viscous-spring boundary was introduced into finite element analysis, which can accurately simulate the incidence at different oblique angles. Then the proposed method was applied in seismic analysis of a gravity dam located in southwest China. The seismic responses under oblique incidence of P-wave and SV-wave at different oblique angles were discussed. The results indicated that the seismic response was obviously influenced by the oblique incidence, and the traditional vertical incidence was unsuitable for some near-field earthquakes. The oblique incidence should be considered in the seismic analysis of high dams as well as other large-scale water-retaining structures located in seismic regions.

Pitting Studies Under Anoxic Conditions on Candidate Container Materials AISI 316L hMo and UHB 904L for The Disposal of HLW in Argillaceous Formations

2003 ◽  
Vol 807 ◽  
Author(s):  
Bruno Kursten ◽  
Frank Druyts
Keyword(s):  
Stainless Steel ◽  
Stainless Steels ◽  
Near Field ◽  
Austenitic Stainless Steels ◽  
Aisi 316L ◽  
Progressive Change ◽  
Anoxic Conditions ◽  
The Impact ◽  
Container Material

ABSTRACTStainless steel is being envisaged as the primary candidate container material for the final disposal of vitrified HLW in deep geological argillaceous formations in Belgium. The impact of an evolving underground repository environment, i.e. a progressive change from oxic to anoxic conditions (due to the consumption of entrapped oxygen), on the pitting behaviour of austenitic stainless steels AISI 316L hMo and UHB 904L was studied. CPP-experiments were performed in synthetic solutions, which are representative for the near-field chemistry of an underground repository. The solutions contained various amounts of Cl- (100–50,000 mg/L) at near-neutral pH. Experiments were conducted at 16 and 90°C.AISI 316L hMo and UHB 904L will not be subjected to immediate pitting problems neither under oxic, nor under anoxic conditions. However, AISI 316L hMo could present long-term pitting problems under oxic conditions. Pits are much easier initiated on AISI 316L hMo, for both oxic and anoxic conditions. The pits propagate in a rather similar manner under oxic conditions for both alloys, whereas under anoxic conditions the pits formed on AISI 316L hMo are much deeper. AISI 316L hMo is more susceptible to crevice attack.

Study of the Impact of Stellite Material on PWR Co-60 Contamination

2017 ◽  
Author(s):  
Liying Zhang ◽  
Yaxiao Wang ◽  
Xiaoxia Wang ◽  
Bo Gao ◽  
Aijun Mi ◽  
...  
Keyword(s):  
Positive Impact ◽  
Occupational Exposures ◽  
High Energy ◽  
Primary Circuit ◽  
Primary Coolant ◽  
Radiation Fields ◽  
Piping Systems ◽  
Energy Gamma ◽  
The Impact

According with the requirements of HAF-102[1], the purpose of radiation protection optimization is to achieve occupational exposures as low as reasonably achievable (ALARA). More than 80% of the collective exposure doses are received during the outage for PWRs. Activated corrosion products, especially Co-60, deposited on the surface of reactor coolant system are the main causes of these doses. Co-60 is the principle contributor to out-of-core radiation fields in PWRs, which is a high energy gamma emitter with a 5.3 year half-life period. The contamination by Co-60 plates out in plant piping systems and produces long term high radiation areas in the plant. Stellite, a hard facing alloy trade, which has high Co-59 content (approximately 60%), is identified as one of the most important source of Co-60 in reactors, whereas the contribution of Stellite to cobalt are always not paid enough attention to. Cobalt is released through ware and corrosion of Stellite. When cobalt is released in systems with a flow path to the reactor, it can become activated by neutron to Co-60. This paper analyzes the Stellite material release into the primary coolant. Based on the above considerations, the impact of Stellite replacement on plant contamination by Co-60 is calculated and analyzed with the use of activated corrosion product source term calculation program. The primary conclusions are as follows: (1) Reducing the quantity of Stellite material used during the design and building of PWRs can significantly reduce the Co-60 deposition on primary circuit. (2) The replacement of Stellite material has a positive impact on PWR contamination by Co-60, but the outcome is not so significant. Based on the above analysis, recommendations are made. Stellite material replacement project can be used for the operating reactors to reduce the Co-60 contamination. But for the design and building of new reactors, reduction of the use of Stellite material is the best choice.

scholarly journals The influence of the fault zone width on land surface vibrations after the high-energy tremor in the “Rydułtowy-Anna” hard coal mine

2018 ◽  
Vol 36 ◽  
pp. 02007 ◽  
Author(s):  
Elżbieta Pilecka ◽  
Dariusz Szwarkowski
Keyword(s):  
Rock Mass ◽  
Fault Zone ◽  
Seismic Wave ◽  
Coal Mine ◽  
Land Surface ◽  
High Energy ◽  
Hard Coal ◽  
Surface Vibrations ◽  
The Impact ◽  
Damage Risk

In the article, a numerical analysis of the impact of the width of the fault zone on land surface tremors on the area of the “Rydułtowy – Anna” hard coal mine was performed. The analysis covered the dynamic impact of the actual seismic wave after the high-energy tremor of 7 June 2013. Vibrations on the land surface are a measure of the mining damage risk. It is particularly the horizontal components of land vibrations that are dangerous to buildings which is reflected in the Mining Scales of Intensity (GSI) of vibrations. The run of a seismic wave in the rock mass from the hypocenter to the area’s surface depends on the lithology of the area and the presence of fault zones. The rock mass network cut by faults of various widths influences the amplitude of tremor reaching the area’s surface. The analysis of the impact of the width of the fault zone was done for three alternatives.

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