scholarly journals SEA-BED CONFIGURATION IN RELATION TO BREAKWATER STABILITY

1972 ◽  
Vol 1 (13) ◽  
pp. 81 ◽  
Author(s):  
J.H. Van Oarschat ◽  
A. Wevers
Keyword(s):  
The Netherlands ◽  
Present Article ◽  
Water Depth ◽  
Systematic Study ◽  
Public Works ◽  
Irregular Waves ◽  
Sea Bed ◽  
Hydraulic Conditions ◽  
Overall Stability ◽  
The Stability

Stability tests on the Europoort breakwaters, situated on a shallow foreshore, clearly demonstrated the effect of the foreshore configuration on the overall stability. The present article gives a descriptionof the stability experiments and the interpretation leading to general conclusions regarding foreshore effects in combination with hydraulic conditions such as wave period, water depth and wave height. Both regular and irregular waves have been used. The experiments, carried out in commission of the Netherlands Government Department of Public Works (Rijkswaterstaat) were of an applied nature and were not directed primarily to the systematic study of foreshore effects.

scholarly journals Stability charts based on the finite element method for underground cavities in soft carbonate rocks: validation through case-study applications

2019 ◽  
Vol 19 (10) ◽  
pp. 2079-2095 ◽  
Author(s):  
Michele Perrotti ◽  
Piernicola Lollino ◽  
Nunzio Luciano Fazio ◽  
Mario Parise
Keyword(s):  
Finite Element ◽  
Safety Margin ◽  
Structural Elements ◽  
The Finite Element Method ◽  
Geometrical Features ◽  
Overall Stability ◽  
Underground Cavities ◽  
The Stability ◽  
Rock Mechanical Properties

Abstract. The stability of man-made underground cavities in soft rocks interacting with overlying structures and infrastructures represents a challenging problem to be faced. Based upon the results of a large number of parametric two-dimensional (2-D) finite-element analyses of ideal cases of underground cavities, accounting for the variability both cave geometrical features and rock mechanical properties, specific charts have been recently proposed in the literature to assess at a preliminary stage the stability of the cavities. The purpose of the present paper is to validate the efficacy of the stability charts through the application to several case studies of underground cavities, considering both quarries collapsed in the past and quarries still stable. The stability graphs proposed by Perrotti et al. (2018) can be useful to evaluate, in a preliminary way, a safety margin for cavities that have not reached failure and to detect indications of predisposition to local or general instability phenomena. Alternatively, for sinkholes that already occurred, the graphs may be useful in identifying the conditions that led to the collapse, highlighting the importance of some structural elements (as pillars and internal walls) on the overall stability of the quarry system.

scholarly journals The stability of major and trace element concentrations from musts to Champagne during the production process

OENO One ◽  
2022 ◽  
Vol 56 (1) ◽  
pp. 29-40
Author(s):  
Robin Cellier ◽  
Sylvain Berail ◽  
Ekaterina Epova ◽  
Julien Barre ◽  
Fanny Claverie ◽  
...  
Keyword(s):  
Trace Elements ◽  
Production Process ◽  
Trace Element ◽  
Narrow Range ◽  
Grape Juice ◽  
Elemental Concentrations ◽  
Element Concentrations ◽  
Production Processes ◽  
Overall Stability ◽  
The Stability

Thirty-nine Champagnes from six different brands originating from the AOC Champagne area were analyzed for major and trace element concentrations in the context of their production processes and in relation to their geographical origins. Inorganic analyses were performed on the must (i.e., grape juice) originating from different AOC areas and the final Champagne. The observed elemental concentrations displayed a very narrow range of variability. Typical concentrations observed in Champagne are expressed in mg/L for elements such as K, Ca, Mg, Na, B, Fe, A, and Mn. They are expressed in µg/L for trace elements such as Sr, Rb, Ba, Cu, Ni, Pb Cr and Li in decreasing order of concentrations. This overall homogeneity was observed for Sr and Rb in particular, which showed a very narrow range of concentrations (150 < Rb < 300 µg/L and 150 < Sr < 350 µg/L) in Champagne. The musts contained similar levels of concentration but showed slightly higher variability since they are directly influenced by the bedrock, which is quite homogenous in the AOC area being studied. Besides the homogeneity of the bedrock, the overall stability of the concentrations recorded in the samples can also be directly linked to the successive blending steps, both at the must level and prior to the final bottling. A detailed analysis of the main additives, sugar, yeast and bentonite, during the Champagne production process, did not show a major impact on the elemental signature of Champagne.

scholarly journals Elements constituent for the design of a riser system in areas deep water and extreme deep water applied for offshore drilling

2020 ◽  
Vol 6 (3) ◽  
pp. 127-144
Author(s):  
Marius STAN ◽  
◽  
Valentin Paul TUDORACHE ◽  
Lazăr AVRAM ◽  
Mohamed Iyad AL NABOULSI ◽  
...  
Keyword(s):  
Working Conditions ◽  
Water Depth ◽  
Deep Water ◽  
Environmental Conditions ◽  
Oil And Gas ◽  
Operational Mode ◽  
Exploration And Exploitation ◽  
Offshore Drilling ◽  
The Stability ◽  
Marine Platform

Riser systems are integral components of the offshore developments used to recover oil and gas stored in the reservoirs below the earth’s oceans and seas. These riser systems are used in all facets of the development offshore process including exploration and exploitation wells completion/intervention, and production of the hydrocarbons. Their primary function is to facilitate the safe transportation of material, oil and gases between the seafloor oceans and seas and the marine platform. As the water depth increases, the working conditions of this system becomes challenging due to the complex forces and extreme environmental conditions which are impacting the operational mode as well as the stability. In this paper several aspects concerning riser mechanics and the behaviour of the riser column will be evaluated against different operational situations.

scholarly journals Study shows low rate of transmission of MRSA in Dutch nursing homes

2003 ◽  
Vol 7 (51) ◽  
Author(s):  
A J de Neeling ◽  
W J B Wannet
Keyword(s):  
Staphylococcus Aureus ◽  
Nursing Homes ◽  
The Netherlands ◽  
Systematic Study ◽  
Methicillin Resistant Staphylococcus Aureus ◽  
Methicillin Resistant ◽  
Low Rate

A systematic study was undertaken from 2000 to 2002 to determine the occurrence of methicillin resistant Staphylococcus aureus (MRSA) in nursing homes in four regions of the Netherlands

A systematic study of the stability, electronic and optical properties of beryllium and nitrogen co-doped graphene

Carbon ◽  
2018 ◽  
Vol 129 ◽  
pp. 207-227 ◽  
Author(s):  
O. Olaniyan ◽  
R.E. Maphasha ◽  
M.J. Madito ◽  
A.A. Khaleed ◽  
E. Igumbor ◽  
...  
Keyword(s):  
Optical Properties ◽  
Systematic Study ◽  
Electronic And Optical Properties ◽  
Doped Graphene ◽  
The Stability ◽  
Co Doped

The Netherlands

2012 ◽  
Author(s):  
Bob Moore
Keyword(s):  
The Netherlands ◽  
Political System ◽  
Social Democracy ◽  
Roman Catholicism ◽  
Islamic Culture ◽  
Small Minority ◽  
General Consensus ◽  
Popular Appeal ◽  
The Stability

There is a general consensus among historians and political scientists that fascism has never had much popular appeal in the Netherlands. The reasons put forward for this view centre on the stability of a Dutch political system epitomized by relatively unchanging voter allegiances and cabinet formation through coalitions of two or more parties. Traditionally, these allegiances were defined primarily by confessional or established ideological positions: Roman Catholicism, Orthodox Calvinism, liberalism, and Social Democracy. More recently, a fear of immigrants and of an increased presence of Islamic culture has helped spawn movements that, if not openly fascist, certainly contain some of the attributes associated with mainstream fascism. The first forms of fascism emerged in the Netherlands during the 1920s, inspired by a small minority who were motivated by admiration for what Mussolini had achieved in Italy.

Defects of monolayer PbI2: a computational study

2021 ◽  
Vol 23 (36) ◽  
pp. 20553-20559
Author(s):  
Han Wang ◽  
Xiao Wang ◽  
Da Li
Keyword(s):  
Dft Calculations ◽  
Electronic Properties ◽  
Systematic Study ◽  
Computational Study ◽  
The Stability ◽  
The Impact

We performed a systematic study on the defects in PbI2 of both 1T and 1H phases by DFT calculations. The stability at the neutral and charged states was calculated. The impact of the defects on the electronic properties was also discussed.

Environmental drivers of benthic communities and habitat heterogeneity on an East Antarctic shelf

2016 ◽  
Vol 29 (1) ◽  
pp. 17-32 ◽  
Author(s):  
Alexandra L. Post ◽  
Caroline Lavoie ◽  
Eugene W. Domack ◽  
Amy Leventer ◽  
Amelia Shevenell ◽  
...  
Keyword(s):  
Water Depth ◽  
Habitat Heterogeneity ◽  
Marine Protected Area ◽  
Regional Distribution ◽  
Benthic Fauna ◽  
Environmental Drivers ◽  
Brittle Stars ◽  
Sea Bed ◽  
Sessile Invertebrates ◽  
Antarctic Shelf

AbstractThis study presents the first analysis of benthic megafauna and habitats from the Sabrina Coast shelf, encompassing a proposed Marine Protected Area. Sea bed imagery indicated an abundant benthic fauna compared to other parts of the Antarctic shelf, dominated by brittle stars, polychaete tubeworms, and a range of other sessile and mobile taxa. The distribution of taxa was related (ρ=0.592, P<0.001) to variations in water depth, latitude, substrate type and phytodetritus. High phytodetritus cover was associated with muddy/sandy sediments and abundant holothurians and amphipods, while harder substrates hosted abundant brachiopods, hard bryozoans, polychaete tubeworms, massive and encrusting sponges, and sea whips. Brittle stars, irregular urchins and anemones were ubiquitous. Variations in substrate largely reflected the distribution of dropstones, creating fine-scale habitat heterogeneity. Several taxa were found only on hard substrates, and their broad regional distribution indicated that the density of dropstones was sufficient for most sessile invertebrates to disperse across the region. The hexactinellid sponge Anoxycalyx joubini and branching hydrocorals exhibited a more restricted distribution, probably related to water depth and limited dispersal capability, respectively. Dropstones were associated with significant increases in taxa diversity, abundance and biological cover, enhancing the overall diversity and biomass of this ecosystem.

scholarly journals Upper and lower limits on the stability of calving glaciers from the yield strength envelope of ice

2011 ◽  
Vol 468 (2140) ◽  
pp. 913-931 ◽  
Author(s):  
J. N. Bassis ◽  
C. C. Walker
Keyword(s):  
Yield Strength ◽  
Water Depth ◽  
Shear Failure ◽  
Ice Sheets ◽  
Direct Consequence ◽  
Ice Thickness ◽  
Tightly Coupled ◽  
The Stability ◽  
Induced Changes ◽  
Lower Limits

Observations indicate that substantial changes in the dynamics of marine-terminating ice sheets and glaciers are tightly coupled to calving-induced changes in the terminus position. However, the calving process itself remains poorly understood and is not well parametrized in current numerical ice sheet models. In this study, we address this uncertainty by deriving plausible upper and lower limits for the maximum stable ice thickness at the calving face of marine-terminating glaciers, using two complementary models. The first model assumes that a combination of tensile and shear failure can render the ice cliff near the terminus unstable and/or enable pre-existing crevasses to intersect. A direct consequence of this model is that thick glaciers must terminate in deep water to stabilize the calving front, yielding a predicted maximum ice cliff height that increases with increasing water depth, consistent with observations culled from glaciers in West Greenland, Antarctica, Svalbard and Alaska. The second model considers an analogous lower limit derived by assuming that the ice is already fractured and fractures are lubricated by pore pressure. In this model, a floating ice tongue can only form when the ice entering the terminus region is relatively intact with few pre-existing, deeply penetrating crevasses.

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