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Spatio-temporal clustering and forecasting method for free-floating bike sharing systems

Free-floating bike sharing systems are an emerging new generation of bike rentals, that eliminates the need for specific stations and allows to leave a bicycle (almost) everywhere in the network. Although free-floating bikes allow much greater spontaneity and flexibility for the user, they need additional operational challenges especially in facing the bike relocation process. Then, we suggest a m

Facing equity in transportation Network Design Problem : A flexible constraints based model

In transportation planning, solutions designed to meet objectives of equity and social inclusion have to be achieved. From this standpoint, most of Network Design Problem (NDP) models aim at identifying the optimal layout of transportation networks by deterministic bi-level problems formulation to reflect the different goals of at least two decision makers (the network users and the planner). Cons

Multi-Agent Planning for Automatic Geospatial Web Service Composition in Geoportals

Automatic composition of geospatial web services increases the possibility of taking full advantage of spatial data and processing capabilities that have been published over the internet. In this paper, a multi-agent artificial intelligence (AI) planning solution was proposed, which works within the geoportal architecture and enables the geoportal to compose semantically annotated Open Geospatial

South‐South Irregular Migration : The Impacts of China's Informal Gold Rush in Ghana

This article examines irregular South‐South migration from China to Ghana, and the role it played in transforming livelihoods and broader developmental landscapes. It looks at the entry of approximately 50,000 Chinese migrants into the informal small‐scale gold mining sector from 2008‐2013. These migrants mainly hailed from Shanglin County in Guangxi Province. In Ghana, they formed mutually benefi

Membrane-based oil-water separation: Membranes, concepts and case studies

1. IntroductionThe demand for efficient oil-water separation is driven by the tightening of discharge limits for e.g. produced water in the oil and gas industry, process water in the petrochemical industry and bilge water in the marine industry. The global produced water production alone is over 71 billion bbl/a – 8.4 billion m3/a [1]. Among the different technologies, particularly ultrafiltration

Membrane processes for a sustainable future: Moving from C2/C3 chemistry to biotechnogical processes

The global society has started a journey from using fossil-based raw material to the utilisation of climate-smart sustainable raw materials. Biorefineries have been identified as one of the backbones of the new bioeconomy using fermentation processes to convert biomass to biofuels and –chemicals and thus replacing the conventional C2/C3 chemistry with biotechnological processes. In current petro-c

Ultrafiltration and nanofiltration of E-stage bleaching plant effluents of a sulphite pulp mill

This work addresses the assessment of ultrafiltration (UF) and nanofiltration (NF) for the treatment of a bleaching plant effluent (BPE) from aPortuguese sulphite pulp mill (Caima-Indústria de Celulose,S.A.) with the two-fold objective of water consumption minimization and by-products valorization. This is to be achieved through the recycling of UF/NF permeates as process water and the concentrati

Meeting the challenges: Membrane processes for water recovery from oily and PVC wastewater

The demand for water recovery in the industry is increasingly important partly due to water shortage and partly due to tightening of regulatory requirements. In this paper water recovery solutions for two challenging types of wastewater - oily and polyvinylchloride (PVC) wastewater - are presented. The first part of the presentation analyses the operation and performance of a membrane unit operate

Membrane separation technologies in biorefineries: Current status and future developments

IntroductionThe start of the 21st century is combined with the continuous replacement of classic C2/C3 chemistry with biological processes. This conversion process started at the end the 20th century and is combined with the integration of membrane processes as high selective and low energy consuming separation technologies in the production of fermentation based products. In fermentation based pr

New concepts for the starch and starch-based sweetener industry

1. IntroductionBoth the development of nowadays membrane technology and nutritive sweeteners started in the middle of the 20th century. The development of the asymmetric membranes using phase inversion was pioneered by Loeb and Sourirajan in the 1960-ies, while the discovery of glucose isomerase was a milestone in the commercialisation of high fructose corn syrup in the beginning of the 1970-ies.

Exploring the structure-properties relationship of novel polyamide thin film composite membranes

Polysulfone (PSf) is a traditional material widely used for manufacturing microfiltration and ultrafiltration membranes by non-solvent induced phase separation (NIPS) process. However, the hydrophobic nature of PSf makes the membranes prone to protein fouling. In order to create non fouling surfaces and further decrease the pore size, the membrane pores can be modified by different strategies as a

The relation between structure-performance of thin film composite membranes and the tools used for their fabrication method

For more than 30 years polyimides (PA) have been one of the main polymers for the fabrication of thin film composite membranes. Several researchers have assessed the main fabrication variables that influence the final structure of the polyamide layers including monomer concentration, solvents, additives in aqueous and organic phases and type of support to mention few [1,2]. However, few studies ha

Separations in biorefineries

1. IntroductionThe starting point of modern biotechnology is often defined by the production of lactic acid by Pasteur in 1857 and the discovery of penicillin by Fleming in 1928. During this first wave of biotechnological processes moved production of e.g. antibiotics and amino acids from laboratory to industrial scale. The second wave of biotechnological processes started with the discovery of th

Multiharmonic Correlations of Different Flow Amplitudes in Pb-Pb Collisions at sNN =2.76 TeV

The event-by-event correlations between three flow amplitudes are measured for the first time in Pb-Pb collisions, using higher-order symmetric cumulants. We find that different three-harmonic correlations develop during the collective evolution of the medium when compared to correlations that exist in the initial state. These new results cannot be interpreted in terms of previous lower-order flow