Search results for "efficien"

Runoff coefficients to predict peak discharge at hillslope scale: A small contribution to theoretical hydrology

2018

The science of hydrology holds a central role in the field of environmental Earth science, being intimately connected to meteorology, climatology, hydrogeology and ecology. In particular, the knowledge of hillslope hydrology is fundamental for understanding the flood phenomenon, for predicting the peak discharge and its probability distribution, which is necessary in many practical applications (design of hydraulic structures, urban, extra-urban planning, etc.). Using different approaches, there have been a multitude of studies on the hydrologic response at hillslope scale. One approach for deriving the hillslope response utilizes, in a distributed form, the differential equations of unstea…

MEASURING PERFORMANCE IN THE PUBLIC SECTOR: BETWEEN NECESSITY AND DIFFICULTY

2014

Performance measurement (PM) in the public sector is indeed a necessity. PM has been introduced in many public organizations in order to ensure transparency of public decisions and the use of public funds and to boost performance. But in practice, this concept strikes many obstacles: defining performance in the public sector, identifying suitable performance indicators, implementation of a performance management system. A challenge, still present, is to identify the most suitable methods for monitoring and measuring performance, so do not give rise to speculative behavior among employees and managers. This paper presents the methods used in measuring performance in the public sector, as wel…

Efficiency Improvement of Permanent-magnet Synchronous Motor Drives for Household Appliances

2011

This paper deals with some aspects of efficiency improvement of PMSMD (Permanent Magnet Synchronous Motor Drives). Particularly two aspects are focused: the control algorithm for the PMSMD, which allows to reduce the power losses of the electric drive without penalty on its dynamic performances and the optimization of an IPMSM (Interior Permanent Magnet Synchronous Motor) rotor configuration capable to increase the performances in terms of shaft torque production, limiting at the same time the rotor leakage flux. The loss minimization algorithm is here briefly analysed, a test bed for experimental validation is presented and the data are analysed. Experimental tests have been performed aimi…

Improvement of partition coefficients determination of aroma compounds in food matrices by the phase ratio variation method

2011

The Phase Ratio Variation (PRV) method is a very valuable method commonly used for liquid/vapor partition coefficients data acquisition of aroma compounds. Nevertheless, some limits are linked to this method, especially for volatile compounds. A careful examination of the PRV equation leads us to propose the following expression: 1/Cvap-real =(nliq/n0) x 1/Cvap-ideal = (nliq/n0) x (1/KC0 + (1/Co) b), We performed an examination for two cases of K values (K1=0.001 and K2=0.05), putting forward that a carefully choice of b range values is crucial for reliability of the regression calculation 1/A versus b.

Energy efficiency and photovoltaic solar for greenhouse agriculture

2011

Ground-Mounted Photovoltaic and Crop Cultivation: A Comparative Analysis

2022

Human civilization depends on energy sources, mainly fossil fuels. An increase in the prices of fossil fuels and their exhaustibility limit economic growth. Carbon dioxide emission causes global environmental problems. Global crises (including COVID-19) have sharpened food and energy supply problems. The decentralized energy supply systems as well as the expedition of the application of renewable energy may solve these challenges. The economic shift to renewable power generation intensifies the competition between food crop production and green energy for land. This paper applied an open-source spatial-based model to quantify the solar power generation (the ground-mounted photovoltaic panel…

Toward Sustainable PLA-Based Multilayer Complexes with Improved Barrier Properties

2019

Poly(lactic acid) or PLA is currently considered as one of the most promising substitutes of conventional plastics, with low environmental impact, especially for food packaging applications. Nevertheless, some drawbacks, such as high permeability to oxygen, are still limiting its industrial applications. The objective of this study was to highly increase the oxygen barrier performance of PLA without compromising its sustainable nature and following the principles of circular economy perspective. Coproducts coming from mill industries, such as wheat gluten proteins (WG), were used to produce PLA-WG-PLA multilayer complexes with improved barrier performance. Different technologies of industri…

Drainage inlets efficiency and its impact on pluvial flooding hazard evaluation uncertainty

2014

Flooding events in urban areas occur quite frequently as a consequence of rain events of lower intensity than the design one, even in case of correct network dimensioning. Inlets are in those cases the critical nodes, and efficient drainage is only ensured when care is taken on their appropriate design and positioning within the pluvial flood-prone areas. Classical approach for design and position of these hydraulic structures can result in high level of uncertainty in defining properly risk levels in urban areas. Further, evaluation of flood hazard in urban areas is made even more difficult if one considers that pluvial flooding can be caused by storm events characterised by a low return t…

Powietrze jako dolne źródło pompy ciepła

2016

W pracy przedstawiono wyniki analiz efektywności energetycznej wykorzystania do ogrzewania budynków jednorodzinnych oraz podgrzewania ciepłej wody użytkowej powietrznych pomp ciepła. Przedstawiono różne rozwiązania dolnych źródeł ciepła pompy wykorzystujących powietrze atmosferyczne lub powietrze z systemu wentylacji budynku. Dokonano również analizy okresu zwrotu inwestycji systemu ogrzewania z wykorzystaniem powietrznej pompy ciepła.

Preparation of tungstophosphoric acid/cerium-doped NH2-UiO-66 Z-scheme photocatalyst: a new candidate for green photo-oxidation of dibenzothiophene a…

2021

International audience; The goal of this study was to introduce an effective visible-light induced photocatalytic system with a good ability for photocatalytic oxidative desulfurization (PODS) and denitrogenation (PODN) using molecular oxygen (O2) as an oxidant. In this regard, tungestophosphoric acid (PW12) was supported onto cerium-doped NH2-UiO-66 (PW12/Ce-NUiO-66) and employed for the photo-oxidation of dibenzothiophene (DBT) and quinoline (Qu). Herein, using cerium (Ce) as a “mediator” facilitated the separation of charge carriers, while NH2-UiO-66 remarkably enhanced the surface area with plentiful adsorption sites and shifted the adsorption edge of PW12to the visible region. The sum …