scholarly journals The impact of disposal of fine-grained sediments from maintenance dredging works on SPM concentration and fluid mud in and outside the harbor of Zeebrugge

2016 ◽  
Vol 66 (11) ◽  
pp. 1497-1516 ◽  
Author(s):  
Michael Fettweis ◽  
Matthias Baeye ◽  
Claudio Cardoso ◽  
Arvid Dujardin ◽  
Brigitte Lauwaert ◽  
...  
Keyword(s):  
Fluid Mud ◽  
Fine Grained ◽  
Spm Concentration ◽  
Maintenance Dredging ◽  
The Impact

scholarly journals Advances in Maintenance of Ports and Waterways: Water Injection Dredging

2021 ◽  
Author(s):  
Alex Kirichek ◽  
Katherine Cronin ◽  
Lynyrd de Wit ◽  
Thijs van Kessel
Keyword(s):  
Water Injection ◽  
Fluid Mud ◽  
Density Currents ◽  
Fine Grained ◽  
Sediment Bed ◽  
Port Authorities ◽  
Monitoring Tools ◽  
Nautical Bottom ◽  
Maintenance Techniques ◽  
Maintenance Dredging

The main objective of this chapter is to demonstrate developments in port maintenance techniques that have been intensively tested in major European ports. As regular port maintenance is highly expensive, port authorities are considering alternative strategies. Water Injection Dredging (WID) can be one of the most efficient alternatives. Using this dredging method, density currents near the bed are created by fluidizing fine-grained sediments. The fluidized sediment can leave the port channels and be transported away from the waterways via the natural force of gravity. WID actions can be successfully coupled with the tidal cycle for extra effectiveness. In addition, WID is combined with another strategy to reduce maintenance dredging: the nautical bottom approach, which enables the vessel to navigate through the WID-induced fluid mud layer. The nautical bottom approach uses the density or the yield stress of sediment to indicate the navigability after WID rather than the absolute depth to the sediment bed. Testing WID-based port maintenance requires thorough preparation. Over the years modeling and monitoring tools have been developed in order to test and optimize WID operations. In this chapter, the application of the recently developed tools is discussed.

scholarly journals Potential Impacts of Future Climate Change Scenarios on Ground Subsidence

Water ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 219 ◽  
Author(s):  
Antonio-Juan Collados-Lara ◽  
David Pulido-Velazquez ◽  
Rosa María Mateos ◽  
Pablo Ezquerro
Keyword(s):  
Climate Change ◽  
Land Subsidence ◽  
Ground Subsidence ◽  
Lower Percentage ◽  
Future Climate Change ◽  
Climate Change Scenarios ◽  
Fine Grained ◽  
Fine Grained Material ◽  
The Impact

In this work, we developed a new method to assess the impact of climate change (CC) scenarios on land subsidence related to groundwater level depletion in detrital aquifers. The main goal of this work was to propose a parsimonious approach that could be applied for any case study. We also evaluated the methodology in a case study, the Vega de Granada aquifer (southern Spain). Historical subsidence rates were estimated using remote sensing techniques (differential interferometric synthetic aperture radar, DInSAR). Local CC scenarios were generated by applying a bias correction approach. An equifeasible ensemble of the generated projections from different climatic models was also proposed. A simple water balance approach was applied to assess CC impacts on lumped global drawdowns due to future potential rainfall recharge and pumping. CC impacts were propagated to drawdowns within piezometers by applying the global delta change observed with the lumped assessment. Regression models were employed to estimate the impacts of these drawdowns in terms of land subsidence, as well as to analyze the influence of the fine-grained material in the aquifer. The results showed that a more linear behavior was observed for the cases with lower percentage of fine-grained material. The mean increase of the maximum subsidence rates in the considered wells for the future horizon (2016–2045) and the Representative Concentration Pathway (RCP) scenario 8.5 was 54%. The main advantage of the proposed method is its applicability in cases with limited information. It is also appropriate for the study of wide areas to identify potential hot spots where more exhaustive analyses should be performed. The method will allow sustainable adaptation strategies in vulnerable areas during drought-critical periods to be assessed.

scholarly journals A Study of the Impact of Graphite on the Kinetics of SPS in Nano- and Submicron WC-10%Co Powder Compositions

Ceramics ◽  
2021 ◽  
Vol 4 (2) ◽  
pp. 331-363
Author(s):  
Eugeniy Lantcev ◽  
Aleksey Nokhrin ◽  
Nataliya Malekhonova ◽  
Maksim Boldin ◽  
Vladimir Chuvil'deev ◽  
...  
Keyword(s):  
Activation Energy ◽  
Solid Phase ◽  
Continuous Heating ◽  
Diffusion Creep ◽  
Hard Alloys ◽  
Fine Grained ◽  
Plasma Sintering ◽  
Spark Plasma ◽  
The Impact ◽  
Kinetics Of

This study investigates the impact of carbon on the kinetics of the spark plasma sintering (SPS) of nano- and submicron powders WC-10wt.%Co. Carbon, in the form of graphite, was introduced into powders by mixing. The activation energy of solid-phase sintering was determined for the conditions of isothermal and continuous heating. It has been demonstrated that increasing the carbon content leads to a decrease in the fraction of η-phase particles and a shift of the shrinkage curve towards lower heating temperatures. It has been established that increasing the graphite content in nano- and submicron powders has no significant effect on the SPS activation energy for “mid-range” heating temperatures, QS(I). The value of QS(I) is close to the activation energy of grain-boundary diffusion in cobalt. It has been demonstrated that increasing the content of graphite leads to a significant decrease in the SPS activation energy, QS(II), for “higher-range” heating temperatures due to lower concentration of tungsten atoms in cobalt-based γ-phase. It has been established that the sintering kinetics of fine-grained WC-Co hard alloys is limited by the intensity of diffusion creep of cobalt (Coble creep).

The impact of business networks on foreign subsidiaries development

IMP Journal ◽  
2018 ◽  
Vol 12 (3) ◽  
pp. 427-443
Author(s):  
Enrico Baraldi ◽  
Francesco Ciabuschi ◽  
Olof Lindahl ◽  
Andrea Perna ◽  
Gian Luca Gregori
Keyword(s):  
Single Case ◽  
Foreign Market ◽  
Business Networks ◽  
International Expansion ◽  
Content Type ◽  
Fine Grained ◽  
Automatic Control Systems ◽  
Industrial Networks ◽  
The Impact

Purpose The purpose of this paper is to explore two specific areas pertaining to industrial networks and international business (IB). First, the authors look at how business relationships influence the internationalization in time, from the establishment of the first subsidiary in a foreign market to the following ones, and in space, that is, across different markets. Second, the authors investigate how an increasing external network dependence of subsidiaries in their internationalization may cause a detachment of a subsidiary from the mother company as its knowledge becomes insufficient to guide a subsidiary’s internationalization. Design/methodology/approach This paper utilizes an exploratory, longitudinal, single-case study of Loccioni – a manufacturer of measuring and automatic control systems for industrial customers – to illustrate the specific dynamics of the influences of industrial networks on the internationalization of subsidiaries. Findings The case study helps to elucidate the roles, entailing also free will and own initiative, of small suppliers’ subsidiaries which operate inside several global factories, and how “surfing” on many different global factories, by means of several local subsidiaries, actually supports these suppliers’ own international developments. This notion adds to our understanding of the global factory phenomenon a supplier focus that stresses how the role of suppliers is not merely that of being passive recipients of activities and directions from a focal orchestrating firm, but can also be that of initiative-takers themselves. Originality/value The paper contributes to the IMP tradition by providing a multi-layered and geographically more fine-grained view of the network embedding companies that operate on internationalized markets. This paper thereby sheds light on a less investigated area of research within the IMP tradition: the link between internationalization in different countries and the interconnectedness between the industrial networks spanning these countries. At the same time, this paper contributes to IB theories by showing how a late-internationalizing SME can enter highly international markets by “plugging into” several established “Global Factories” as a way to exploit further opportunities for international expansion.

scholarly journals A model for coupled electro-hydro-mechanical processes in fine grained soils accounting for gas generation and transport

2010 ◽  
Vol 82 (1) ◽  
pp. 169-193 ◽  
Author(s):  
Claudio Tamagnini ◽  
Cristina Jommi ◽  
Fabio Cattaneo
Keyword(s):  
Pore Space ◽  
Transport Coefficients ◽  
Gas Production ◽  
Degree Of Saturation ◽  
Coupled Processes ◽  
Gas Generation ◽  
Fine Grained ◽  
Clayey Silt ◽  
Waste Containment Systems ◽  
The Impact

A theoretical and numerical model is developed for the quantitative analysis of coupled processes taking place in active waste containment systems, such as electrokinetic barriers or fences, in which alow intensity DC current is circulated across the clay barrier to move polar and non-polar contaminants. A novel feature of the proposed approach is the allowance for the presence of air in the pore space. Under unsaturated conditions, all transport coefficients involved in the electrokinetic process are strongly dependent on the degree of saturation of pore liquid. In order to assess the predictive capability of the proposed theory and to appreciate the impact of gas production at the electrodes, a series of numerical simulations of simple onedimensional electrokinetic tests have been performed. The results of the simulations compare reasonably well with data obtained from laboratory experiments performed on an illitic clayey silt. The numerical results indicate that the impact of gas production at the electrodes can be significant, even in low-intensity and short-duration treatments.

scholarly journals Stream plant chemistry as indicator of acid sulphate soils in Sweden

2008 ◽  
Vol 14 (1) ◽  
pp. 83 ◽  
Author(s):  
K. LAX
Keyword(s):  
Surface Waters ◽  
Stream Water ◽  
Low Ph ◽  
Fontinalis Antipyretica ◽  
Acid Sulphate ◽  
Fine Grained ◽  
Acid Sulphate Soils ◽  
Trace Element Chemistry ◽  
Study Results ◽  
The Impact

Results from the biogeochemical mapping (roots of aquatic plants and Fontinalis antipyretica) conducted by the Geological Survey of Sweden (SGU) reflects the metal load of surface waters draining acid sulphate (AS) soils in Sweden. In this study, results from the biogeochemical, soil geochemical and Quaternary mapping programmes at SGU were used to investigate the impact of fine-grained deposits hosting AS soils on stream water trace element chemistry in two separate areas. In the area around Lake Mälaren, postglacial sediments contain the highest levels of most trace elements studied. Owing to the low pH of AS soils and subsequent leaching, levels of nickel (Ni), cobalt (Co), copper (Cu), sulphur (S), yttrium (Y), uranium (U), tungsten (W), and molybdenum (Mo) were significantly elevated in aquatic roots. Levels were lower in the Skellefteå area, which may be explained by lower concentrations in source deposits. Concentrations of arsenic (As) and lead (Pb) were normal or impoverished in biogeochemical samples from postglacial, finegrained sediment areas. Maps based on ratios (Ni:Pb or Y:Pb) in biogeochemical samples can, together with results from Quaternary mapping, be used to predict areas with AS soils in Sweden.;

scholarly journals Denudation systematics inferred from in situ cosmogenic <sup>10</sup>Be concentrations in fine (50–100 µm) and medium (100–250 µm) sediments of the Var River basin, southern French Alps

2019 ◽  
Vol 7 (4) ◽  
pp. 1059-1074 ◽  
Author(s):  
Apolline Mariotti ◽  
Pierre-Henri Blard ◽  
Julien Charreau ◽  
Carole Petit ◽  
Stéphane Molliex ◽  
...  
Keyword(s):  
Glacial Cycles ◽  
Size Fractions ◽  
French Alps ◽  
Fine Grained ◽  
Denudation Rates ◽  
Variable Morphology ◽  
Cosmogenic 10Be ◽  
The Impact ◽  
Quartz Grains

Abstract. Marine sedimentary archives are well dated and often span several glacial cycles; cosmogenic 10Be concentrations in their detrital quartz grains could thus offer the opportunity to reconstruct a wealth of past denudation rates. However, these archives often comprise sediments much finer (<250 µm) than typically analyzed in 10Be studies, and few studies have measured 10Be concentrations in quartz grains smaller than 100 µm or assessed the impacts of mixing, grain size, and interannual variability on the 10Be concentrations of such fine-grained sediments. Here, we analyzed the in situ cosmogenic 10Be concentrations of quartz grains in the 50–100 and 100–250 µm size fractions of sediments from the Var basin (southern French Alps) to test the reliability of denudation rates derived from 10Be analyses of fine sands. The Var basin has a short transfer zone and highly variable morphology, climate, and geology, and we test the impact of these parameters on the observed 10Be concentrations. Both analyzed size fractions returned similar 10Be concentrations in downstream locations, notably at the Var's outlet, where concentrations ranged from (4.02±0.78)×104 to (4.40±0.64)×104 atoms g−1 of quartz. By comparing expected and observed 10Be concentrations at three major river junctions, we interpret that sediment mixing is efficient throughout the Var basin. We resampled four key locations 1 year later, and despite variable climatic parameters during that period, interannual 10Be concentrations were in agreement within uncertainties, except for one upper subbasin. The 10Be-derived denudation rates of Var subbasins range from 0.10±0.01 to 0.57±0.09 mm yr−1, and spatial variations are primarily controlled by the average subbasin slope. The integrated denudation rate of the entire Var basin is 0.24±0.04 mm yr−1, in agreement with other methods. Our results demonstrate that fine-grained sediments (50–250 µm) may return accurate denudation rates and are thus potentially suitable targets for future 10Be applications, such as studies of paleo-denudation rates using offshore sediments.

scholarly journals Geospatial Analysis and Mapping Strategies for Fine Grained and Detailed COVID-19 Data With Geographic Information Systems

2021 ◽  
Author(s):  
ÁNGEL MIRAMONTES CARBALLADA ◽  
JOSE BALSA-BARREIRO
Keyword(s):  
Geographic Location ◽  
Social Contact ◽  
Temporal Behaviour ◽  
Fine Grained ◽  
Health Authorities ◽  
Public Health Authorities ◽  
Spatio Temporal ◽  
Media Reports ◽  
Predictive Risk ◽  
The Impact

Abstract The CoVID-19 pandemic is showing a dramatic impact across the world. To the tragedy of the loss of human lives, we must add the great uncertainty that the new coronavirus is causing to our lives. Governments and public health authorities must be able to respond this emergency by taking the appropriate decisions for minimizing the impact of the virus. In the absence of an immediate solution, governments have concentrated their efforts on adopting non-pharmaceutical interventions for restricting the mobility of people and reducing the social contact. Health authorities are publishing most of data for supporting their interventions and policies. The geographic location of the cases is a vital information with exceptional value for analysing the spatio-temporal behaviour of the virus, doing feasible to anticipate potential outbreaks and to elaborate predictive risk mapping. In fact, a great number of media reports, research papers, and web-browsers have presented the COVID-19 disease spreading by using maps. However, processing and visualization of this sort of data presents some aspects that must be carefully reviewed. Based on our experience with fine-grained and detailed data related to COVID-19 in a Spanish region, we present a bunch of mapping strategies and good practices using geospatial tools. The ultimate goal is create appropriate maps at any spatial scale while avoiding conflicts with data such as those related to patients’ privacy.

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