Search results for "gradient"

Active lighting applied to three dimensional reconstruction of specular metallic surfaces by polarization imaging

2005

This thesis deals with a new automated tridimensional inspection system for specular metallic surfaces, based on polarization analysis. We first present an extension of the ‘Shape from Polarization' method for dielectric to metallic surfaces. After being reflected, an unpolarized light wave becomes partially linearly polarized, depending on the surface normal and on the refractive index of the media it impinges on. Hence, by measuring the polarization parameters of the reflected light, the surface normals are computed. The ambiguity concerning the normals orientation is solved here with a new active lighting system. Then, we describe and compare numerical methods for reconstructing the trid…

Optimal Heating of an Indoor Swimming Pool

2020

This work presents the derivation of a model for the heating process of the air of a glass dome, where an indoor swimming pool is located in the bottom of the dome. The problem can be reduced from a three dimensional to a two dimensional one. The main goal is the formulation of a proper optimization problem for computing the optimal heating of the air after a given time. For that, the model of the heating process as a partial differential equation is formulated as well as the optimization problem subject to the time-dependent partial differential equation. This yields the optimal heating of the air under the glass dome such that the desired temperature distribution is attained after a given…

Performance analysis of the first Reverse Electrodialysis prototype plant operating with natural brackish water and salt pond brine

2014

Reverse Electrodialysis (RED) has gained a strong interest among the salinity gradient energy technologies during the last years. Recently, notable improvements have been reached in terms of membranes and stack performances using artificial solutions. However, the use of real saline solutions strongly affects the process performance, requiring additional R&D efforts for a successful scale-up of such technology. This work focuses on the experimental campaign performed on the first RED prototype plant fed with real brackish water and saltworks brine. The plant is located within the Ettore e Infersa saltworks in Marsala (TP, South of Italy). It is the final accomplishment of the REAPower proje…

Optimisation analysis of Reverse Electrodialysis systems for power production from concentrated brines

2016

Reverse Electrodialysis (RED) is rapidly growing as technology to produce electric energy by mixing saline solutions with different salinity. Recent developments have shown promising results on real site installations, demonstrating the feasibility of the RED process on the pilot scale. Therefore, further modelling efforts are now needed to optimise the technology, in order to enhance the performance. In this work, an optimisation study for the RED process is presented, taking into account saline waters and concentrated brine as feed streams. The model, which is developed within GAMS environment, predicts the optimal set of process variables that maximise the process yield, as well as the g…

Yhtälöryhmän iteratiivinen ratkaiseminen

2015

PLLA Scaffold via TIPS for Bone Tissue Engineering

2016

Tissue engineering offers a promising new approach to repair bone fractures, fractures that do not heal, and fractures due to bone tumors. In this work, two different approaches were tested in order to obtain Poly-L- Lactic Acid (PLLA) porous scaffolds via Thermally Induced Phase Separation (TIPS) for bone tissue engineering application. First, the possibility to produce a composite material, by incorporating Hydroxyapatite (HA) particles in a Poly-L-lactic acid (PLLA) matrix was investigated. Two PLLA/HA weight ratios (70/30 and 50/50) were tested. The results showed that the presence of HA does not influence the phase separation process, i.e. the composite scaffolds microstructure is simi…

Examination of coagulant additives on qualitative composition of selected thermal waters

2017

On the territory of Poland occur rich deposits of thermal waters. Although the utilisation of these waters is continuously extending, Poland is not exploiting their full geothermal potential due to high investment costs. Thermal waters industry in Poland to date indicates operations within mainly balneology as well as recreation objectives. Higher temperature values of these waters foster a washout in the surrounding rocks resulting in a high concentration of diluted substances which must be often removed. The following study investigates thermal waters from three intakes for which coagulation processes were conducted. Research clearly shows that coagulant additives not impact on the qualit…

An Approach to Delineate Groundwater Bodies at Risk: Seawater Intrusion in Liepāja (Latvia)

2018

Groundwater quality in coastal areas is frequently affected by seawater intrusion as a consequence of intensive water consumption. To achieve “good chemical status” of a groundwater body according to Water Framework Directive the effects of saline or other intrusions should not be observed. Groundwater pumping in former decades has caused a significant seawater intrusion into confined aquifer in Liepāja and has led to deterioration of relatively wide coastal area of the third largest city in Latvia. However, the area affected by seawater intrusion is a small part of groundwater body F1 which overall chemical status is good. Thus, no specific management measures have been applied to explore …

Peer review report 1 on âControls on runoff generation along a steep climatic gradient in the Eastern Mediterraneanâ

2017

Resonance in Interacting Induced-Dipole Polarizing Force Fields: Application to Force-Field Derivatives

2009

The Silberstein model of the molecular polarizability of diatomic molecules, generalized by Applequist et al. for polyatomic molecules, is analyzed. The atoms are regarded as isotropically polarizable points located at their nuclei, interacting via the fields of their induced dipoles. The use of additive values for atom polarizabilities gives poor results, in some cases leading to artificial predictions of absorption bands. The molecular polarizability of methane and its derivative are computed. The agreement with experimental mean molecular polarizabilities is within 1–5%. A hypothesis is indispensable for a suitable representation of polarizability derivative.