Geotechnical Approach to Early-Stage Site Characterisation of Shallow Wave Energy Sites

Marine renewable energy is still in its infancy and poses serious challenges due to the harsh marine conditions encountered for wave or tidal installations and the survivability of devices. Geophysical and hydrodynamic initial site surveys need to be able to provide repeatable, reliable, and economical solutions. An oscillating water column wave energy converter is to be installed on the west coast of King Island, Tasmania. The location is in a high-energy nearshore environment to take advantage of sustained shoaling non-breaking waves of the Southern Ocean and required site-specific information for the deployment. We provide insight into scalable geophysical site surveys capable of capturing large amounts of data within a short time frame. This data was incorporated into a site suitability model, utilising seabed slope, sediment depth, and water depth to provide the terrain analysis needed to match deployment-specific characteristics. In addition, short-term hydrology and geotechnical work found a highly energetic seabed (near seafloor water velocities <1 m/s) with sufficient bearing capacity (6 MPa). In a highly energetic environment, care was taken to collect the relevant data needed for an assessment of critical information to an emerging technology companies primary project. This is in addition to the malleable methodology for a site suitability model that can incorporate various weighted parameters to prioritise the location for shallow wave energy sites in general.

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Variations of wave energy power in shoaling zone of Benin coastal zone

International Journal of Renewable Energy Development ◽

10.14710/ijred.4.1.64-71 ◽

2015 ◽

Vol 4 (1) ◽

pp. 64-71

Author(s):

Mathias A. Houekpoheha ◽

Basile B. Kounouhewa ◽

Joël T. Hounsou ◽

Bernard N. Tokpohozin ◽

Jean V. Hounguevou ◽

...

Keyword(s):

Wave Energy ◽

Boussinesq Equations ◽

Population Level ◽

Electrical Energy ◽

Breaking Waves ◽

High Energy ◽

Fossil Energy ◽

Deep Waters ◽

Stokes Waves ◽

Local Water

Today, we observe at the population level, that the improvement in comfort is accompanied by an increase in the electrical energy required. The predicted exhaustion of fossil energy resources maintains some speculation. Their unequal geographical distribution justifies the energy dependence of Benin overlooked from outside. So it is urgent to explore the various sources of renewable energy available to Benin. In this work, using measurements made by the Millennium Challenge Account (MCA-Benin) as part of the extension of the port of Cotonou, with Boussinesq equations (Peregrine) and Stokes waves dispersion relation, we characterized the variations of various swell parameters (height, wavelength, velocities) in the shoaling zone on the study site and proceeded to estimate variations in wave energy power from deep waters to the bathymetric breaking point. Finally, the zone with high energy power (where the conversion of this energy into electrical energy would be profitable) of these waves is highlighted on the site, the local water depth at the point of breaking waves is evaluated and results obtained allowed to justify the very energetic character take by these swells on this coast when they are close to the beach.

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Evaluation of Energy Absorption Capabilities of Polyethylene Foam under Impact Deformation

Materials ◽

10.3390/ma14133613 ◽

2021 ◽

Vol 14 (13) ◽

pp. 3613

Author(s):

Baohui Yang ◽

Yangjie Zuo ◽

Zhengping Chang

Keyword(s):

Energy Absorption ◽

Failure Modes ◽

High Strain ◽

Early Stage ◽

High Energy ◽

Test Method ◽

Test Theory ◽

Strain Rates ◽

Impact Properties ◽

The Impact

Foams are widely used in protective applications requiring high energy absorption under impact, and evaluating impact properties of foams is vital. Therefore, a novel test method based on a shock tube was developed to investigate the impact properties of closed-cell polyethylene (PE) foams at strain rates over 6000 s−1, and the test theory is presented. Based on the test method, the failure progress and final failure modes of PE foams are discussed. Moreover, energy absorption capabilities of PE foams were assessed under both quasi-static and high strain rate loading conditions. The results showed that the foam exhibited a nonuniform deformation along the specimen length under high strain rates. The energy absorption rate of PE foam increased with the increasing of strain rates. The specimen energy absorption varied linearly in the early stage and then increased rapidly, corresponding to a uniform compression process. However, in the shock wave deformation process, the energy absorption capacity of the foam maintained a good stability and exhibited the best energy absorption state when the speed was higher than 26 m/s. This stable energy absorption state disappeared until the speed was lower than 1.3 m/s. The loading speed exhibited an obvious influence on energy density.

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Diffusion of heavy quarks in the early stage of high-energy nuclear collisions at energies available at the BNL Relativistic Heavy Ion Collider and at the CERN Large Hadron Collider

Physical Review C ◽

10.1103/physrevc.102.044902 ◽

2020 ◽

Vol 102 (4) ◽

Author(s):

J. H. Liu ◽

S. Plumari ◽

S. K. Das ◽

V. Greco ◽

M. Ruggieri

Keyword(s):

Large Hadron Collider ◽

Early Stage ◽

Hadron Collider ◽

Heavy Ion ◽

High Energy ◽

Heavy Quarks ◽

Relativistic Heavy Ion Collider ◽

Cern Large Hadron Collider ◽

Nuclear Collisions

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LOS ARRECIFES DE LA ISLA DE SAN ANDRÉS (MAR CARIBE, COLOMBIA)

Bulletin of Marine and Coastal Research ◽

10.25268/bimc.invemar.1973.7.0.553 ◽

2016 ◽

Vol 7 ◽

Cited By ~ 3

Author(s):

Jörn Geister

Keyword(s):

Wave Energy ◽

Maximum Degree ◽

Caribbean Sea ◽

High Energy ◽

Reef Crest ◽

Acropora Palmata ◽

Reef Complex ◽

Western Caribbean ◽

The Caribbean ◽

San Andres

The windward reef complex NE and E of San Andrés Island is briefly described in terms of submarine topography, sediments and the distribution of corals and other benthonic organisms. The breaker zone of the San Andrés barrier and other exposed Western Caribbean reefs characteristically exhibits a profuse growth consisting almost exclusively of Millepora. In this respect they are different from most other described West Indian reef localities, where Acropora palmata is the dominating species in this part of the reef. The replacement of Acropora palmata by Millepora is interpreted as an adaptation of the reef crest community to high energy environments due to long swell prevailing at the Western end of the Caribbean Sea. A few short reef sections exposed to the maximum degree of wave energy show conspicuous algal ridges.

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Control over patch encounters changes foraging behaviour

10.1101/2021.01.19.426950 ◽

2021 ◽

Author(s):

Sam Hall-McMaster ◽

Peter Dayan ◽

Nicolas W. Schuck

Keyword(s):

Computational Model ◽

Optimal Strategy ◽

Decision Problem ◽

Foraging Behaviour ◽

Specific Information ◽

Natural Environments ◽

Average Reward ◽

Reward Rate ◽

A Site ◽

A Current

SummaryForaging is a common decision problem in natural environments. When new exploitable sites are always available, a simple optimal strategy is to leave a current site when its return falls below a single average reward rate. Here, we examined foraging in a more structured environment, with a limited number of sites that replenished at different rates and had to be revisited. When participants could choose sites, they visited fast-replenishing sites more often, left sites at higher levels of reward, and achieved a higher net reward rate. Decisions to exploit-or-leave a site were best explained with a computational model estimating separate reward rates for each site. This suggests option-specific information can be used to construct a threshold for patch leaving in some foraging settings, rather than a single average reward rate.

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NMR microsystem for label-free characterization of 3D nanoliter microtissues

10.1101/2020.04.26.062141 ◽

2020 ◽

Author(s):

Marco Grisi ◽

Gaurasundar M. Conley ◽

Kyle J. Rodriguez ◽

Erika Riva ◽

Lukas Egli ◽

...

Keyword(s):

Early Stage ◽

Cmos Technology ◽

Time Frame ◽

Ease Of Use ◽

Chemical Information ◽

Spectroscopic Techniques ◽

Label Free ◽

Alcoholic Fatty Liver ◽

Non Invasive

AbstractPerforming chemical analysis at the nanoliter (nL) scale is of paramount importance for medicine, drug development, toxicology, and research. Despite the numerous methodologies available, a tool for obtaining chemical information non-invasively is still missing at this scale. Observer effects, sample destruction and complex preparatory procedures remain a necessary compromise1. Among non-invasive spectroscopic techniques, one able to provide holistic and highly resolved chemical information in-vivo is nuclear magnetic resonance (NMR)2,3. For its renowned informative power and ability to foster discoveries and life-saving applications4,5, efficient NMR at microscopic scales is highly sought after6–10, but so far technical limitations could not match the stringent necessities of microbiology, such as biocompatible handling, ease of use, and high throughput. Here we introduce a novel microsystem, which combines CMOS technology with 3D microfabrication, enabling nL NMR as a platform tool for non-invasive spectroscopy of organoids, 3D cell cultures, and early stage embryos. In this study we show its application to microlivers models simulating non-alcoholic fatty liver disease (NAFLD), demonstrating detection of lipid metabolism dynamics in a time frame of 14 days based on 117 measurements of single 3D human liver microtissues.

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Abstract 144: Zebrafish Larvae: A Model System for Early Stage Atherosclerosis?

Arteriosclerosis Thrombosis and Vascular Biology ◽

10.1161/atvb.35.suppl_1.144 ◽

2015 ◽

Vol 35 (suppl_1) ◽

Author(s):

Manoj K Bandaru ◽

Petter Ranefall ◽

Anastasia Emmanouilidou ◽

Tiffany Klingström ◽

Lingjie Tao ◽

...

Keyword(s):

Early Stage ◽

Association Studies ◽

Oxidized Ldl ◽

Control Diet ◽

High Energy ◽

Model System ◽

Genome Wide Association Studies ◽

Lipid Deposition ◽

Zebrafish Larvae ◽

Starting Point

Objectives: Published results show that overfeeding zebrafish larvae on a high-cholesterol diet (HCD) can result in hypercholesterolemia and sub-endothelial lipid deposition in macrophages and other cell types. However, results are so far based on small samples, and the atherogenic response has been heterogeneous. We aim to use zebrafish larvae for large-scale, CRISPR-Cas9-based genetic screens, using results from genome wide association studies for coronary heart disease as a starting point. Firstly however, we need to ensure the model system is appropriate and robust. Therefore, we examined the effect of a high-energy diet (HED) and HCD on vascular lipid deposition in a larger number of larvae (n=241). Methods: Starting at 5 days post fertilization (dpf), ~30 larvae/tank were fed 2x/day on: 1) 5 mg control diet (CD; n=33); 2) 15 mg control diet (HED; n=90); or 3) 15 mg control diet enriched with 4% cholesterol (HCD; n=94). At 14-17 dpf, larvae were soaked in monodansylpentane cadaverase - a lipid staining dye - for 45 min, before imaging the dorsal aorta and caudal vein with a Leica SP5 confocal microscope. We used a custom written script in Cell Profiler to quantify the surface area of lipid deposits in the vasculature. Results: Manual annotation of vascular lipid deposition in 30 images (10 randomly selected images per dietary condition) allowed us to calculate the sensitivity (36%) and specificity (71%) of the Cell Profiler script. Subsequent analyses showed that HED (p=0.004) and HCD (p=0.001) fed larvae have significantly more vascular lipid deposition than CD fed larvae after adjusting for age, batch and vessel length. There was no difference in vascular lipid deposition between HED and HCD fed larvae (p=0.11). Discussion and conclusion: Our results confirm that zebrafish larvae represent a promising model system for early-stage atherosclerosis. In addition, they show that enriching the diet with cholesterol is not required to prompt atherogenesis. Future directions: In the next few months, we will examine if overfeeding also triggers vascular infiltration by macrophages, neutrophils and oxidized LDL cholesterol, and if atherogenesis can be prevented or reduced by treating larvae with statins and/or ezetimibe, using our new, automated imaging setup.

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Modeling Migratory Patterns of the Eastern Monarch Butterfly

International Journal of Applied Geospatial Research ◽

10.4018/ijagr.2020100103 ◽

2020 ◽

Vol 11 (4) ◽

pp. 42-63

Author(s):

Karen Kesler ◽

Rick Bunch

Keyword(s):

Monarch Butterfly ◽

The Other ◽

Site Suitability ◽

Average Temperature ◽

Migratory Cycle ◽

Migratory Patterns ◽

Data Layers ◽

A Site ◽

And Behavior ◽

Agriculture Development

The purpose of this research was to relate the influence of specific site suitability variables to eastern monarch butterfly migratory patterns and behavior. Elevation, temperature, precipitation, and land use data layers were overlaid to collectively consider how these variables affected the way that butterflies migrated and recolonized during the 2016/2017 migratory cycle. The variables were reclassified into layers ranking suitability as either unsuitable, suitable, or optimal with respective scores of one, three, and five. Three uninhabitable variables were identified that deemed a site unsuitable despite the influence and possible optimal suitability of the other variables. The results of this study indicated that site suitability was a large driving factor for migratory monarchs with a heavier emphasis placed on average temperature and land/cropland use. Possible displaced and sink populations were identified for further study, while the effects of agriculture, development, and climate change were considered regarding flyway connectivity and behavior.

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Description and paleobiogeographic significance of a rare Cenomanian molluscan faunule from Bathurst Island, northern Australia

Journal of Paleontology ◽

10.1017/s0022336000037306 ◽

2002 ◽

Vol 76 (3) ◽

pp. 447-471 ◽

Cited By ~ 6

Author(s):

Jeffrey D. Stilwell ◽

Robert A. Henderson

Keyword(s):

Southern Hemisphere ◽

Large Scale ◽

Early Stage ◽

High Energy ◽

Global Scale ◽

Nominal Species ◽

Oceanic Circulation ◽

Northern Australia ◽

Continental Shelves ◽

Deposit Feeding

A middle Cenomanian faunule from the Moonkinu Formation of Bathurst Island in Northern Australia contains the best-preserved suite of benthic Mollusca known from the Cretaceous of the Australian region. Twenty-four species of bivalves, gastropods, and scaphopods, many exquisitely preserved with original aragonitic nacre, are recognized. Thirteen are new: Nucula s.l. meadinga n. sp. (Nuculidae), Nuculana bathurstensis n. sp. (Nuculanidae), Jupiteria? n. sp. A (Nuculanidae), Varicorbula cretaustrina n. sp. (Corbulidae), Vanikoropsis demipleurus n. sp. (Vanikoridae), Euspira n. sp. A (Naticidae), Amuletum praeturriformis n. sp. (Turridae), Granosolarium cretasteum n. sp. (Architectonicidae), Echinimathilda moonkinua n. sp. (Mathildidae), Acteon bathurstensis n. sp. (Acteonidae), Biplica antichthona n. sp. (Ringiculidae), Goniocylichna australocylindricata n. sp. (Cylichnidae), and Dentalium (Dentalium) n. sp. A (Dentaliidae). Nominal species of Nuculana, Grammatodon, Cylichna, and Laevidentalium also are present. The occurrence of ammonites, including taxa that occur in the type Cenomanian, securely establishes the fauna as middle Cenomanian (Acanthoceras rhotomagense Zone). The Moonkinu Formation and its faunule were deposited in a high-energy, shallow-shelfal setting, as part of a large-scale regressive cycle recognized as the Money Shoals Platform of northern Australia. The assemblage represents a parauthochthonous suite which experienced little or no post mortem transport. Epifaunal and infaunal suspension feeders (some 60 percent) dominate the bivalve fauna with a subordinate representation of deposit-feeding infaunal burrowers (some 40 percent). Nearly all of the gastopods were carnivores with the aporrhaid Latiala mountnorrisi (Skwarko), probably a deposit feeder, the only exception. The scaphopods were probably micro-carnivores. Concentrations of the ammonite Sciponoceras glaessneri are likely the result of mass kills in surface waters. The cosmopolitan nature of the Bathurst Island fauna at the genus-level reflects unrestricted oceanic circulation patterns and an equitable climate on a global scale during the Cenomanian. The retreat and disappearance of the Australian epicontinental sea at the close of the Albian coincided with reduced endemism in the molluscan faunas, after which time the continental shelves hosted a rich suite of cosmopolitan affinity. The high number of endemic species in the Moonkinu Formation probably represents an early stage of broad-scale genetic separation among Southern Hemisphere molluscan stocks, a trend that became increasingly pronounced through the Late Cretaceous. The new records of Varicorbula, Amuletum, Granosolarium, Echinimathilda, and Goniocylichna represent the oldest occurrences recorded for these genera and are suggestive of Southern Hemisphere origins.

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