Multi-Scale Numerical Analysis of the Field Efficiency of an Ocean Plastic Cleanup Array

2016 ◽  
Author(s):  
Bruno Sainte-Rose ◽  
Laurent Lebreton ◽  
Joao de Lima Rego ◽  
Frank Kleissen ◽  
Julia Reisser
Keyword(s):  
Global Economy ◽  
Spatial Scales ◽  
Target Area ◽  
Japanese Island ◽  
Plastic Pollution ◽  
Plastic Debris ◽  
Multi Scale ◽  
Effective Manner ◽  
Field Efficiency ◽  
The Impact

The impact of plastic pollution on marine ecosystems and global economy has been drawing public concern since the end of the 20th century. To mitigate this issue, The Ocean Cleanup (TOC) Foundation is developing technologies to extract, prevent, and intercept plastic debris from coastal and oceanic environments. The core technology being optimized is the use of floating booms placed perpendicular to the main ocean plastic flow so it can concentrate plastic debris to a point where it can be extracted, shipped and processed in a cost-effective manner. In order to optimize the system’s field efficiency (i.e. mass of ocean plastic captured per length of floating boom), a multi-scale approach has been elaborated, where temporal and spatial scales span over several orders of magnitude. Here we introduce this general multi-scale method alongside its assumptions and multi-scale models. We then describe two application examples, the first corresponding to our coastal pilot in the Japanese island of Tsushima and the second related to our main cleanup target area: the so-called Great Pacific Garbage Patch, situated between Hawaii and the US west coast.

Hydrodynamics and Capture Efficiency of Plastic Cleanup Booms: Part I — Experiments and Dynamic Analysis

2017 ◽  
Author(s):  
Roberto Brambini ◽  
Bénédicte Dommergues ◽  
Hannah Maral ◽  
Bruno Sainte-Rose
Keyword(s):  
Dynamic Analysis ◽  
Global Economy ◽  
Vertical Plane ◽  
Cost Effective ◽  
Analysis Model ◽  
Plastic Pollution ◽  
Plastic Debris ◽  
Cfd Models ◽  
Core Technology ◽  
Effective Manner

To reduce the threatening consequences of plastic pollution on marine ecosystems and global economy, The Ocean Cleanup (TOC) Foundation develops technologies to extract, prevent, and intercept plastic debris from coastal and oceanic environments. The core technology being optimized is the use of floating booms placed perpendicular to the main ocean plastic flow so it can concentrate plastic debris to a point where it can be extracted, shipped and processed in a cost-effective manner. To better understand the behavior of such a system in the vertical plane and to calibrate dynamic analysis models as well as Computational Fluid Dynamics (CFD) models, TOC conducted model tests of a portion of the boom at 1:5 scale. These tests were carried out in the Concept Basin at the Maritime Research Institute of the Netherlands (MARIN). The aim of this paper is to present those tests along with the assessment of the dynamics of the boom and the validation of a dynamic analysis model to predict the mooring loads on the system.

Hydrodynamics and Capture Efficiency of Plastic Cleanup Booms: Part II — 2D Vertical Capture Efficiency and CFD Validation

2017 ◽  
Author(s):  
Bénédicte Dommergues ◽  
Roberto Brambini ◽  
René Mettler ◽  
Zaki Abiza ◽  
Bruno Sainte-Rose
Keyword(s):  
Global Economy ◽  
Cost Effective ◽  
Capture Efficiency ◽  
Cfd Model ◽  
Plastic Pollution ◽  
Cfd Validation ◽  
Plastic Debris ◽  
The Core ◽  
Core Technology ◽  
Effective Manner

To mitigate the growing impact of plastic pollution on marine ecosystems and global economy, The Ocean Cleanup (TOC) Foundation develops technologies to extract, prevent, and intercept plastic debris from coastal and oceanic environments. The core technology being optimized is the use of floating booms placed perpendicular to the main ocean plastic flow so it can concentrate plastic debris to a point where it can be extracted, shipped and processed in a cost-effective manner. To investigate the capture efficiency of such a system, TOC conducted model scaled tests at the Dutch research institute MARIN. The objective of this paper is to present those tests along with the assessment of an hydrodynamic model and a CFD model to predict the dynamics of a rigid boom on one hand and the validation of this CFD model to predict the capture efficiency of such a boom.

scholarly journals Validation of a Pattern Scaling Approach for Determining the Maximum Available Renewable Freshwater Resource

2014 ◽  
Vol 15 (1) ◽  
pp. 505-516 ◽  
Author(s):  
Yasuhiro Ishizaki ◽  
Tokuta Yokohata ◽  
Seita Emori ◽  
Hideo Shiogama ◽  
Kiyoshi Takahashi ◽  
...  
Keyword(s):  
Large Scale ◽  
Basic Assumption ◽  
Spatial Scales ◽  
Global Climate Models ◽  
Target Area ◽  
Emission Scenarios ◽  
Anthropogenic Aerosol ◽  
Freshwater Resource ◽  
Wide Range ◽  
The Impact

Abstract A pattern scaling approach allows projection of regional climate changes under a wide range of emission scenarios. A basic assumption of this approach is that the spatial response pattern to global warming (scaling pattern) is the same for all emission scenarios. Precipitation minus evapotranspiration (PME) over land can be considered to be a measure of the maximum available renewable freshwater resource, and estimation of PME is fundamentally important for the assessment of water resources. The authors assessed the basic assumption of pattern scaling for PME by the use of five global climate models. A significant scenario dependency (SD) of the scaling pattern of PME was found over some regions. This SD of the scaling pattern of PME was mainly due to the SD and the nonlinear response of large-scale atmospheric and oceanic changes. When the SD of the scaling pattern of PME is significant in a target area, projections of the impact of climate change need to carefully take into consideration the SD. Although the SD of the anthropogenic aerosol scaling patterns tended to induce SDs of precipitation and evapotranspiration scaling patterns, the SDs of precipitation and evapotranspiration tended to cancel each other out. As a result, the SD of the PME scaling pattern tended to be insignificant over most regions where the SD of anthropogenic aerosol scaling patterns were significant. The authors could not find large impacts of land use change on PME scaling pattern, but the former may influence the latter on different time scales or spatial scales.

Multi-scale shear impacts during the genesis of Hagupit (2008)

2020 ◽  
Author(s):  
Chaehyeon C. Nam ◽  
Michael M. Bell
Keyword(s):  
Tropical Cyclone ◽  
Doppler Radar ◽  
Negative Impact ◽  
Early Stage ◽  
Spatial Scales ◽  
Deep Convection ◽  
Vertical Wind Shear ◽  
Low Level ◽  
Multi Scale ◽  
The Impact

AbstractThe impact of vertical wind shear (VWS) on tropical cyclogenesis is examined from the synoptic to meso scales using airborne Doppler radar observations of pre-depression Hagupit during the Tropical Cyclone Structure 2008 (TCS08) / THORPEX Pacific Area Regional Campaign (T-PARC) field campaigns. The high temporal and spatial resolution observations reveal complex localized convective and vortical characteristics of a pre-depression in a sheared environment. Pre-depression Hagupit interacted with an upper-tropospheric trough during the observation period. The strong deep-layer VWS (> 20 m s−1) had a negative impact on the development through misalignment of the low and mid-level circulations and dry air intrusion. However, the low-level circulation persisted and the system ultimately formed into a tropical cyclone after it left the high-shear zone. Here we propose that a key process that enabled the pre-depression to survive through the upper-tropospheric trough interaction was persistent vorticity amplification on the meso-γ scale that was aggregated on the meso-α scale within the wave pouch. Multi-Doppler wind analysis indicates that cumulus congestus tilted the low-level horizontal vorticity into the vertical in the early stage of convective life-cycle, followed by stretching from maturing deep convection. Variations in low-level VWS on the meso-β scale affect convective organization and horizontal vorticity generation. The results provide new insights into multi-scale processes during TC genesis and the interactions of a pre-depression with VWS at various spatial scales.

scholarly journals MuSCA: a multi-scale model to explore carbon allocation in plants

2018 ◽  
Author(s):  
F. Reyes ◽  
B. Pallas ◽  
C. Pradal ◽  
F. Vaggi ◽  
D. Zanotelli ◽  
...  
Keyword(s):  
Spatial Scale ◽  
Field Data ◽  
Carbon Allocation ◽  
Spatial Scales ◽  
Computation Time ◽  
Fruit Growth ◽  
Scale Model ◽  
Growth Unit ◽  
Multi Scale ◽  
The Impact

ABSTRACTBackground and aimsCarbon allocation in plants is usually represented at a specific spatial scale, peculiar to each model. This makes the results obtained by different models, and the impact of their scale of representation, difficult to compare. In this work we developed a Multi Scale Carbon Allocation model (MuSCA) that can be applied at different, user-defined, topological scales of a plant, and used to assess the impact of each spatial scale on simulated results and computation time.MethodsModel multi-scale consistency and behavior were tested by applications on three realistic apple tree structures. Carbon allocation was computed at five spatial scales, spanning from the metamer (the finest scale, used as a reference) up to 1st order branches, and for different values of a sap friction coefficient. Fruit dry mass increments were compared across spatial scales and with field data.Key ResultsThe model showed physiological coherence in representing competition for carbon assimilates. Results from intermediate values of the friction parameter best fitted the field data. For these, fruit growth simulated at the metamer scale (considered as a reference) differed from about 1% at growth unit scale up to 35% at first order branch scale. Generally, the coarser the spatial scale the more fruit growth diverged from the reference and the lower the obtained within-tree fruit growth variability. Coherence in the carbon allocated across scales was also differently impacted, depending on the tree structure considered. Decreasing the topological resolution reduced computation time up to four orders of magnitude.ConclusionsMuSCA revealed that the topological scale has a major influence on the simulation of carbon allocation, suggesting that this factor should be carefully evaluated when using different carbon allocation models or comparing their results. Trades-off between computation time and prediction accuracy can be evaluated by changing topological scales.

scholarly journals Impact of Plastic Debris on the Gut Microbiota of Caretta caretta From Northwestern Adriatic Sea

2021 ◽  
Vol 8 ◽  
Author(s):  
Elena Biagi ◽  
Margherita Musella ◽  
Giorgia Palladino ◽  
Valeria Angelini ◽  
Sauro Pari ◽  
...  
Keyword(s):  
Adriatic Sea ◽  
Caretta Caretta ◽  
Marine Ecosystems ◽  
Sea Turtle ◽  
Marine Organisms ◽  
Pollution Level ◽  
Flagship Species ◽  
Plastic Pollution ◽  
Plastic Debris ◽  
The Impact

Plastic pollution is nowadays a relevant threat for the ecological balance in marine ecosystems. Small plastic debris (PD) can enter food webs through various marine organisms, with possible consequences on their physiology and health. The loggerhead sea turtle (Caretta caretta), widespread across the whole Mediterranean Sea, is a “flagship species,” useful as indicator of the general pollution level of marine ecosystems. Ingested PD accumulate in the final section of turtles’ digestive tract before excretion. During their transit and accumulation, PD also interact with the residing microbial community, with possible feedback consequences on the host’s health. To explore the possible relationship between fecal microbial composition and PD ingestion, we collected fecal samples from 45 turtles rescued between 2017 and 2019 in the Northwestern Adriatic Sea (Italy), assessing occurrence and content of PD in the samples and in parallel the microbiome structure by 16S rRNA gene sequencing. According to our findings, almost all samples contained PD, mirroring the high level of plastic pollution in the area. We identified phylotypes associated to a high amount of PD, namely Cetobacterium somerae and other taxa, possibly responding to contamination by plastic-associated chemicals. Furthermore, putative marine pathogens were found associated to higher plastic contamination, supporting the hypothesis that PD can act as a carrier for environmental pathogenic bacteria into marine organisms. Besides confirming the role of the sea turtle as relevant flagship species for plastic pollution of the marine environment, our study paves the way to the exploration of the impact that PD ingestion can have on the microbial counterpart of large marine organisms, with potential feedback consequences on the animal and ecosystem health.

Forecasting US movies box office performances in Turkey using machine learning algorithms

2020 ◽  
Vol 39 (5) ◽  
pp. 6579-6590
Author(s):  
Sandy Çağlıyor ◽  
Başar Öztayşi ◽  
Selime Sezgin
Keyword(s):  
Machine Learning ◽  
Global Economy ◽  
Learning Algorithms ◽  
Forecast Model ◽  
Machine Learning Algorithms ◽  
Gradient Boosting ◽  
High Stakes ◽  
Box Office ◽  
Industry Forecast ◽  
The Impact

The motion picture industry is one of the largest industries worldwide and has significant importance in the global economy. Considering the high stakes and high risks in the industry, forecast models and decision support systems are gaining importance. Several attempts have been made to estimate the theatrical performance of a movie before or at the early stages of its release. Nevertheless, these models are mostly used for predicting domestic performances and the industry still struggles to predict box office performances in overseas markets. In this study, the aim is to design a forecast model using different machine learning algorithms to estimate the theatrical success of US movies in Turkey. From various sources, a dataset of 1559 movies is constructed. Firstly, independent variables are grouped as pre-release, distributor type, and international distribution based on their characteristic. The number of attendances is discretized into three classes. Four popular machine learning algorithms, artificial neural networks, decision tree regression and gradient boosting tree and random forest are employed, and the impact of each group is observed by compared by the performance models. Then the number of target classes is increased into five and eight and results are compared with the previously developed models in the literature.

International trade: Research of the reasons for the fall

2019 ◽  
pp. 79-91 ◽  
Author(s):  
V. S. Nazarov ◽  
S. S. Lazaryan ◽  
I. V. Nikonov ◽  
A. I. Votinov
Keyword(s):  
Growth Rate ◽  
International Trade ◽  
Exchange Rate ◽  
Global Economy ◽  
Structural Changes ◽  
Global Value Chains ◽  
Value Chains ◽  
Negative Contribution ◽  
Basic Commodity ◽  
The Impact

The article assesses the impact of various factors on the growth rate of international trade. Many experts interpreted the cross-border flows of goods decline against the backdrop of a growing global economy as an alarming sign that indicates a slowdown in the processes of globalization. To determine the reasons for the dynamics of international trade, the decompositions of its growth rate were carried out and allowed to single out the effect of the dollar exchange rate, the commodities prices and global value chains on the change in the volume of trade. As a result, it was discovered that the most part of the dynamics of international trade is due to fluctuations in the exchange rate of the dollar and prices for basic commodity groups. The negative contribution of trade within global value chains in 2014 was also revealed. During the investigated period (2000—2014), such a picture was observed only in the crisis periods, which may indicate the beginning of structural changes in the world trade.

Structural Modeling of Institute of Entrepreneurship in Russia

2019 ◽  
pp. 34-48
Author(s):  
Svetlana L. Sazanova
Keyword(s):  
Global Economy ◽  
Structural Model ◽  
Institutional Environment ◽  
Small And Medium Enterprises ◽  
Structural Modeling ◽  
Entrepreneurial Activity ◽  
Pattern Modeling ◽  
Medium Enterprises ◽  
The Impact ◽  
The Relationship

Entrepreneurship plays an important role in the modern global economy; the share of products of small and medium enterprises in the gross product and exports not only of the developed but also of developing countries is growing. Innovation processes cover all sectors of the economy, and more and more people are involved in entrepreneurial activity, which contributes to the penetration of entrepreneurial thinking and business values in all areas of the socioeconomic life of society. The Institute of Entrepreneurship plays an increasingly prominent role in the institutional environment of socio-economic systems. This actualizes the problem of studying the relationship of the institution of entrepreneurship with the institutions of law, culture, management. This requires a methodology that allows you to explore the impact on the institute of entrepreneurship not only economic, but also non-economic factors. The methodology of the “old” institutionalism possesses such a tool, it is structural modeling (pattern modeling), which allows to explore the diversity of interrelationships of the institution of entrepreneurship with other components of the institutional and economic environment. The article explored the features of the development of the institution of entrepreneurship in Russia, established the relationship between the institution of entrepreneurship, values, motives and incentives for entrepreneurial activity, built a structural model of the institution of entrepreneurship based on the methodology of the old institutionalism (pattern modeling). The structural model of the institution of entrepreneurship reveals the relationship between the institution of entrepreneurship, the values of entrepreneurial activity, its motives and incentives; as well as the relationship between the institution of entrepreneurship with the institutions of governance, cultural and religious institutions, legal institutions and society.

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