Records |
Author |
Prabhakara, V. |
Title |
Strain measurement for semiconductor applications with Raman spectroscopy and Transmission electron microscopy |
Type |
Doctoral thesis |
Year |
2021 |
Publication |
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Pages |
149 p. |
Keywords |
Doctoral thesis; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Scaling down the size of transistors has been a trend for several decades which has led to improved transistor performance, increased transistor density and hence the overall computation power of IC chips. The trend slowed in recent years due to reliability and power consumption issues at the nanoscale. Hence strain is introduced into transistor channels that has beneficial effects on improving the mobility of charge carriers, providing an alternative pathway for enhancing transistor performance. Therefore, monitoring strain is vital for the semiconductor industry. With the recent trend of decreasing device dimensions (FinFETS ~ 10-20nm) and strain modulation being used throughout, industry needs a reliable and fast method as quality control or defect characterisation. Such a universal strain measurement method does not exist, and one relies on a combination of quantitative in-line methods and complex off-line approaches. In this thesis, I investigated TEM and Raman spectroscopy-based methodologies for strain measurement. In terms of TEM methodologies, advancements are made for the STEM moiré imaging, targeting strain spatial resolution enhancement. I introduce advanced quadrature demodulation and phase stepping interferometry applied to STEM moiré that greatly enhances the spatial resolution while providing enhanced field of view and sensitivity for strain measurement. We introduce ways to reduce scan distortions in strain maps using an alternative scan strategy called “Block scanning” and the non-linear regression applied for strain extraction. Prospects for 3D strain analysis using high-resolution tomography is also investigated which gives direct access for the full second order strain tensors calculation. Finally, we compare strain measurements from TEM techniques with inline techniques like Raman spectroscopy. Raman stress measurement involves sensitive identification of the TO and LO phonon peaks. Raman spectrum of strained Ge transistor channel consists of strongly overlapping peaks within the spectral resolution of the spectrometer. Hence, the process of deconvolution of the two peaks is rather challenging. Hence, we explore new polarisation geometries like radially polarised incoming light which was shown to ease the deconvolution problem resulting in improved precision for Raman stress–strain measurements. |
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Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:182261 |
Serial |
6847 |
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Author |
Shi, R.; Choudhuri, D.; Kashiwar, A.; Dasari, S.; Wang, Y.; Banerjee, R.; Banerjee, D. |
Title |
α phase growth and branching in titanium alloys |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Philosophical magazine |
Abbreviated Journal |
Philos Mag |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The morphology and spatial distribution of alpha (α) precipitates have been mapped as a function of Mo content in Ti-Mo binary alloys employing a combinatorial approach. Heat-treatments were carried out on compositionally graded Ti-xMo samples processed using a rapid throughput laser engineered net shape (LENS) process. The composition space spans 1.5 at% to 6 at% Mo with ageing at 750°C, 650°C and 600°C following a β solution treatment. Three distinct regimes of α morphology and distribution were observed. These are colony-dominated microstructures originating from grain boundary α allotriomorphs, bundles of intragranular α laths, and homogeneously distributed individual fine-scale α laths. Branching of the α precipitates was observed in all these domains in a manner reminiscent of solid-state dendritic growth. The phenomenon is particularly apparent at low volume fractions of α. Similar features are present in a wide variety of alloy compositions. 3-dimensional features of such branched structures have been analysed. Simulation of the branching process by phase field methods incorporating anisotropy in the α/β interface energy and elasticity suggests that it can be initiated at growth ledges present at broad faces of the α laths, driven by the enhancement of the diffusion flux at these steps. The dependence of branching on various parameters such as supersaturation and diffusivity, and microstructural features like ledge height and distribution and the presence of adjacent α variants has been evaluated. |
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000722082700001 |
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2021-11-24 |
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1478-6435 |
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UA library record; WoS full record |
Impact Factor |
1.505 |
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Not_Open_Access |
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Most recent IF: 1.505 |
Call Number |
UA @ admin @ c:irua:183616 |
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6849 |
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Zhang, Z.; Bourgeois, L.; Zhang, Y.; Rosalie, J.M.; Medhekar, N. |
Title |
Advanced imaging and simulations of precipitate interfaces in aluminium alloys and their role in phase transformations |
Type |
P1 Proceeding |
Year |
2020 |
Publication |
MATEC web of conferences
T2 – 17th International Conference on Aluminium Alloys (ICAA), October 26-29, 2020 |
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Pages |
09003 |
Keywords |
P1 Proceeding; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Precipitation is accompanied by the formation and migration of heterophase interfaces. Using the combined approach of advanced imaging and atomistic simulations, we studied the precipitate-matrix interfaces in various aluminium alloy systems, aiming to resolve their detailed atomic structures and illuminate their role in phase transformations. |
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000652552200053 |
Publication Date |
2020-11-05 |
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Series Volume |
326 |
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2261-236x; 2274-7214 |
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UA library record; WoS full record |
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Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:179147 |
Serial |
6851 |
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Author |
Velazco Torrejón, A. |
Title |
Alternative scan strategies for high resolution STEM imaging |
Type |
Doctoral thesis |
Year |
2021 |
Publication |
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Pages |
131 p. |
Keywords |
Doctoral thesis; Electron microscopy for materials research (EMAT) |
Abstract |
Currently, a large variety of materials are studied by transmission electron microscopy (TEM) as it offers the possibility to perform structural and elemental analysis at a local scale. Relatively recent advances in aberration correctors and electron sources allow the instrument to achieve atomic resolution. Along with these advances, a state-of-the-art technology has been reached in TEM. However, the instrument is far from being perfect and imperfections or external sources can make the interpretation of information troublesome. Environmental factors such as acoustic and mechanical vibrations, temperature fluctuations, etc., can induce sample drift and create image distortions. These distortions are enhanced in scanning operation because of the serial acquisition of the information, which are more apparent at atomic resolution as small field of views are imaged. In addition, scanning distortions are induced due to the finite time response of the scan coils. These types of distortions would reduce precision in atomic-scale strain analysis, for instance, in semiconductors. Most of the efforts to correct these distortions are focused on data processing techniques post-acquisition. Another limitation in TEM is beam damage effects. Beam damage arises because of the energy transferred to the sample in electron-sample interactions. In scanning TEM, at atomic resolution, the increased electron charge density (electron dose) carried on a sub-Å size electron probe may aggravate beam damage effects. Soft materials such as zeolites, organic, biological materials, etc., can be destroyed under irradiation limiting the amount of information that can be acquired. Current efforts to circumvent beam damage are mostly based on low electron dose acquisitions and data processing methods to maximize the signal at low dose conditions. In this thesis, a different approach is given to address drift and scanning distortions, as well as beam damage effects. Novel scan strategies are proposed for that purpose, which are shown to substantially overcome these issues compared to the standard scan method in TEM. |
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Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:180973 |
Serial |
6852 |
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Author |
Roegiers, J. |
Title |
Development of combined photocatalytic and active carbon fiber technology for indoor air purification based on Multiphysics models |
Type |
Doctoral thesis |
Year |
2021 |
Publication |
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Abbreviated Journal |
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Issue |
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Pages |
XXX, 197 p. |
Keywords |
Doctoral thesis; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
Exposure to volatile organic compounds (VOCs) remains a major public health concern. Indoor VOC concentrations typically far exceed outdoor levels due to a variety of emission sources and the stringent insulation measures that are imposed today. Many attempts have been made to use photocatalysis for indoor air purification. In an ideal situation, photocatalysis is capable of complete mineralization of VOCs to H2O and CO2, without any byproduct formation. Moreover, the process can take place at standard atmospheric conditions, i.e. ambient temperature and atmospheric pressure. However, successful exploitation is still impeded due to low conversion efficiency, significant pressure loss (and hence a high energy consumption) and byproduct formation. In the first part of this thesis an attempt was made to tackles these problems by designing a novel type of photocatalytic (PCO) reactor. The PCO device consists of a cylindrical vessel filled with TiO2-coated glass tubes and equipped with UV fluorescence lamps. It was investigated in terms of fluid dynamics, coating properties, UV-light distribution and photocatalytic activity. Experimental data was later used to develop and calibrate a Multiphysics model. The model proved to be a useful tool for designing and upscaling the PCO reactor. Consequently, an optimized prototype reactor was constructed and tested according the CEN-EN-16846-1 standard for VOC removal. Although the prototype showed promising results for lab-scale conditions, it struggled with byproduct formation when purifying ppb-level VOCs. In the second part of this thesis, activated carbon adsorption was investigated in order to combine it with photocatalysis. Activated carbon fiber was opted for its fast kinetics, high adsorption capacity and thermo-electrical regeneration. The filter was studied in detail regarding the adsorption of polar and apolar VOCs at indoor air concentration levels and regeneration capabilities. Experimental data was used to develop a Multiphysics model for activated carbon adsorption as well. Consequently, a novel type of ACF filter was developed using the Multiphysics model, which was equipped with electrodes in the tips of the pleats for effective thermal regeneration. In the last part, the combination of both ACF and PCO was studied using a realistic case study. Based on the Multiphysics model, the feasibility of a so-called hybrid air purification device could be investigated. The Multiphysics model shows promising results for this hybrid PCO-ACF system and hence, a demo setup was constructed for future research. |
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Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:181137 |
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6860 |
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Author |
Guzzinati, G.; Ghielens, W.; Mahr, C.; Béché, A.; Rosenauer, A.; Calders, T.; Verbeeck, J. |
Title |
Electron Bessel beam diffraction patterns, line scan of Si/SiGe multilayer |
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2019 |
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Dataset; ADReM Data Lab (ADReM); Electron microscopy for materials research (EMAT) |
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no |
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UA @ admin @ c:irua:169114 |
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6865 |
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Author |
Guzzinati, G.; Das, P.P.; Zompra, A., A.; Nicopoulos, S.; Verbeeck, J. |
Title |
Electron energy loss spectra of several organic compounds |
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Dataset |
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2020 |
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Dataset; Electron microscopy for materials research (EMAT) |
Abstract |
We placed crystals of different compounds to explore the possibility of fingerprinting them through EELS. Here are representative datasets of 7 different compounds: b-cyclodextrin hexacarboxy cyclohexane tannin TH-15 peptide TH-27 peptide two different forms of piroxicam The datasets were collected at EMAT, using a monochromated FEI Titan3 TEM, within the scope of an EUSMI request. More information as well as analysis methodologies adopted for the data are detailed in the paper: Das et al. “Reliable Characterization of Organic & Pharmaceutical Compounds with High Resolution Monochromated EEL Spectroscopy”, Polymers 2020, 12(7), 1434. |
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Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:180654 |
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6866 |
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Author |
De wael, A. |
Title |
Model-based quantitative scanning transmission electron microscopy for measuring dynamic structural changes at the atomic scale |
Type |
Doctoral thesis |
Year |
2021 |
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xiv, 146 p. |
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Doctoral thesis; Electron microscopy for materials research (EMAT) |
Abstract |
Nanomaterialen kunnen uiterst interessante eigenschappen vertonen voor een verscheidenheid aan veelbelovende toepassingen, gaande van zonnecrème tot batterijen voor elektrische auto’s. Een nanometer is een miljard keer kleiner dan een meter. Op deze schaal kunnen de materiaaleigenschappen volledig verschillen van bulkmaterialen op grotere schaal. Bovendien hangen de eigenschappen van nanomaterialen sterk af van hun exacte grootte en vorm. Kleine verschillen in de posities van de atomen, in de grootte-orde van een picometer (nog eens duizend maal kleiner dan een nanometer), kunnen de fysische eigenschappen al drastisch beïnvloeden. Daarom is een betrouwbare kwantificering van de atomaire structuur van kritisch belang om de evolutie naar materiaalontwerp mogelijk te maken en inzicht te verwerven in de relatie tussen de fysische eigenschappen en de structuur van nanomaterialen. Daarnaast kan de atomaire structuur van nanomaterialen ook veranderen in de loop van de tijd ten gevolge van verschillende fysische processen. Het onderzoek dat in deze thesis gepresenteerd wordt, maakt het mogelijk om de dynamische structuurveranderingen van nanomaterialen betrouwbaar te kwantificeren op atomaire schaal door gebruik te maken van raster transmissie elektronenmicroscopie (STEM). Ik heb dit gerealiseerd door methodes te ontwikkelen waarmee ik het aantal atomen “achter elkaar” kan tellen in elke atoomkolom van een nanomateriaal, en dit op basis van beelden opgenomen met een elektronenmicroscoop. Een belangrijk verschil met telmethodes voor de analyse van een enkel beeld is het schatten van de kans dat een atoomkolom atomen zal verliezen of bijkrijgen van het ene naar het andere beeld in de tijdreeks. Deze kwantitatieve methode kan het ontrafelen van de tijdsafhankelijke structuur-eigenschappen relatie van een nanomateriaal mogelijk maken, wat uiteindelijk kan leiden tot efficiënter design en productie van nanomaterialen voor innovatieve toepassingen. |
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Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:179514 |
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6870 |
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Author |
Jannis, D. |
Title |
Novel detection schemes for transmission electron microscopy |
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Doctoral thesis |
Year |
2021 |
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iv, 208 p. |
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Doctoral thesis; Electron microscopy for materials research (EMAT) |
Abstract |
Electron microscopy is an excellent tool which provides resolution down to the atomic scale with up to pm precision in locating atoms. The characterization of materials in these length scales is of utmost importance to answer questions in biology, chemistry and material science. The successful implementation of aberration-corrected microscopes made atomic resolution imaging relatively easy, this could give the impression that the development of novel electron microscopy techniques would stagnate and only the application of these instruments as giant magnifying tools would continue. This is of course not true and a multitude of problems still exist in electron microscopy. Two of such issues are discussed below. One of the biggest problems in electron microscopy is the presence of beam damage which occurs due the fact that the highly energetic incoming electrons have sufficient kinetic energy to change the structure of the material. The amount of damage induced depends on the dose, hence minimizing this dose during an experiment is beneficial. This minimizing of the total dose comes at the expense of more noise due to the counting nature of the electrons. For this reason, the implementation of four dimensional scanning transmission electron microscopy (4D STEM) experiments has reduced the total dose needed per acquisition. However, the current cameras used to measure the diffraction patterns are still two orders of magnitude slower than to the conventional STEM methods. Improving the acquisition speed would make the 4D STEM technique more feasible and is of utmost importance for the beam sensitive materials since less dose is used during the acquisition. In TEM there is not only the possibility to perform imaging experiments but also spectroscopic measurements. There are two frequently used methods: electron energy-loss spectroscopy (EELS) and energy dispersive x-ray spectroscopy (EDX). EELS measures the energy-loss spectrum of the incoming electron which gives information on the available excitations in the material providing elemental sensitivity. In EDX, the characteristic x-rays, arising from the decay of an atom which is initially excited due to the incoming electrons, are detected providing similar elemental analysis. Both methods are able to provide comparable elemental information where in certain circumstances one outperforms the other. However, both methods have a detection limit of approximately 100-1000 ppm which is not sufficient for some materials. In this thesis, two novel techniques which can make significant progress for the two problems discussed above. |
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UA @ admin @ c:irua:182404 |
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6872 |
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Liang, Q.; Yang, D.; Xia, F.; Bai, H.; Peng, H.; Yu, R.; Yan, Y.; He, D.; Cao, S.; Van Tendeloo, G.; Li, G.; Zhang, Q.; Tang, X.; Wu, J. |
Title |
Phase-transformation-induced giant deformation in thermoelectric Ag₂Se semiconductor |
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A1 Journal article |
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2021 |
Publication |
Advanced Functional Materials |
Abbreviated Journal |
Adv Funct Mater |
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2106938 |
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A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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In most semiconducting metal chalcogenides, a large deformation is usually accompanied by a phase transformation, while the deformation mechanism remains largely unexplored. Herein, a phase-transformation-induced deformation in Ag2Se is investigated by in situ transmission electron microscopy, and a new ordered high-temperature phase (named as alpha '-Ag2Se) is identified. The Se-Se bonds are folded when the Ag+-ion vacancies are ordered and become stretched when these vacancies are disordered. Such a stretch/fold of the Se-Se bonds enables a fast and large deformation occurring during the phase transition. Meanwhile, the different Se-Se bonding states in alpha-, alpha '-, beta-Ag2Se phases lead to the formation of a large number of nanoslabs and the high concentration of dislocations at the interface, which flexibly accommodate the strain caused by the phase transformation. This study reveals the atomic mechanism of the deformation in Ag2Se inorganic semiconductors during the phase transition, which also provides inspiration for understanding the phase transition process in other functional materials. |
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000695142800001 |
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2021-09-13 |
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1616-301x |
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UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.124 |
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Most recent IF: 12.124 |
Call Number |
UA @ admin @ c:irua:181527 |
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6879 |
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Samaeeaghmiyoni, V.; Cordier, P.; Demouchy, S.; Bollinger, C.; Gasc, J.; Mussi, A.; Schryvers, D.; Idrissi, H. |
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Research data supporting for Stress-induced amorphization triggers deformation in the lithospheric mantle |
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2020 |
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Dataset; Electron microscopy for materials research (EMAT) |
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UA @ admin @ c:irua:180668 |
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6881 |
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Guzzinati, G.; Béché, A.; McGrouther, D.; Verbeeck, J. |
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Rotation of electron beams in the presence of localised, longitudinal magnetic fields |
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2019 |
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Dataset; Electron microscopy for materials research (EMAT) |
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Electron Bessel beams have been generated by inserting an annular aperture in the illumination system of a TEM. These beams have passed through a localised magnetic field. As a result a low amount of image rotation (which is expected to be proportional to the longitudinal component of the magnetic field) is observed in the far field. A measure of this rotation should give access to the magneti field. The two datasets have been acquired in a FEI Titan3 microscope, operated at 300kV. The file focalseries.tif contains a series of images acquired varying the magnetic field through the objective lens. The file lineprofile.ser contains a series of images acquired by scanning the beam over a sample with several magnetised nanopillars. For reference, check the associated publication. |
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UA @ admin @ c:irua:169135 |
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6883 |
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Jannis, D.; Müller-Caspary, K.; Béché, A.; Oelsner, A.; Verbeeck, J. |
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Spectrocopic coincidence experiment in transmission electron microscopy |
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2019 |
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Dataset; Electron microscopy for materials research (EMAT) |
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This dataset contains individual EEL and EDX events where for every event (electron or X-ray), their energy and time of arrival is stored. The experiment was performed in a transmission electron microscope (Tecnai Osiris) at 200 keV. The material investigated is an Al-Mg-Si-Cu alloy. The 'full_dataset.mat' contains the full dataset and the 'subset.mat' has the first five frames of the full dataset. The attached 'EELS-EDX.ipynb' is a jupyter notebook file. This file describes the data processing in order to observe the temporal correlation between the electrons and X-rays. |
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UA @ admin @ c:irua:169112 |
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6888 |
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Idrissi, H.; Samaee, V.; Lumbeeck, G.; van der Werf, T.; Pardoen, T.; Schryvers, D.; Cordier, P. |
Title |
Supporting data for “In situ Quantitative Tensile Tests on Antigorite in a Transmission Electron Microscope” |
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2019 |
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Dataset; Electron microscopy for materials research (EMAT) |
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The determination of the mechanical properties of serpentinites is essential towards the understanding of the mechanics of faulting and subduction. Here, we present the first in situ tensile tests on antigorite in a transmission electron microscope. A push-to-pull deformation device is used to perform quantitative tensile tests, during which force and displacement are measured, while the microstructure is imaged with the microscope. The experiments have been performed at room temperature on beams prepared by focused ion beam. The specimens are not single crystals despite their small sizes. Orientation mapping indicated that some grains were well-oriented for plastic slip. However, no dislocation activity has been observed even though engineering tensile stress went up to 700 MPa. We show also that antigorite does not exhibit an pure elastic-brittle behaviour since, despite the presence of defects, the specimens underwent plastic deformation and did not fail within the elastic regime. Instead, we observe that strain localizes at grain boundaries. All observations concur to show that under our experimental conditions, grain boundary sliding is the dominant deformation mechanism. This study sheds a new light on the mechanical properties of antigorite and calls for further studies on the structure and properties of grain boundaries in antigorite and more generally in phyllosilicates. |
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no |
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UA @ admin @ c:irua:169107 |
Serial |
6891 |
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Author |
Penders, A.; Konstantinovic, M.J.; Van Renterghem, W.; Bosch, R.W.; Schryvers, D. |
Title |
TEM investigation of SCC crack tips in high Si stainless steel tapered specimens |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Corrosion Engineering Science And Technology |
Abbreviated Journal |
Corros Eng Sci Techn |
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A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The stress corrosion cracking (SCC) mechanism is investigated in high Si duplex stainless steel in a simulated PWR environment based on TEM analysis of FIB-extracted SCC crack tips. The microstructural investigation in the near vicinity of SCC crack tips illustrates a strain-rate dependence in SCC mechanisms. Detailed analysis of the crack tip morphology, that includes crack tip oxidation and surrounding deformation field, indicates the existence of an interplay between corrosion- and deformation-driven failure as a function of the strain rate. Slow strain-rate crack tips exhibit a narrow cleavage failure which can be linked to the film-induced failure mechanism, while rounded shaped crack tips for faster strain rates could be related to the strain-induced failure. As a result, two nominal strain-rate-dependent failure regimes dominated either by corrosion or deformation-driven cracking mechanisms can be distinguished. |
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000695956400001 |
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2021-09-14 |
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1478-422x |
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UA library record; WoS full record; WoS citing articles |
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0.879 |
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OpenAccess |
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Most recent IF: 0.879 |
Call Number |
UA @ admin @ c:irua:181533 |
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6892 |
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Author |
Peeters, M. |
Title |
The added value of Smart Product-Service Systems to real estate developments |
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Doctoral thesis |
Year |
2021 |
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117 p. |
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Doctoral thesis; Economics; Engineering Management (ENM); Internet Data Lab (IDLab) |
Abstract |
Socially responsible investments can be defined as an investment process that integrates ethical values and environmental protection, improving social conditions, and good governance into a traditional investment decision. This integration is mainly a consequence of the growing importance that investors give to environmental, social, and governance (ESG) criteria, resulting in more sustainable development. Also, in the real estate sector, increased attention is being paid to the contributions made to integrate economic, environmental, and social factors into decisions. The ESG framework looks closely at how companies are managed, and the impact related to their market value. The factors for investors’ focus are summarized as environmental, social, and governance. The term ESG was coined in a 2004 United Nations (UN) report titled “Who Cares Wins,” aimed at raising awareness regarding the importance of environmental, social, and corporate governance issues in financial markets. The ESG criteria’s specific purpose is to guide investors in recognizing sustainable investments without evaluating how sustainable the asset is or the investment value represented by sustainability. It is essential to underline that ESG does not take specific economic interests into account. The rationale behind this apparent gap is that investors investigate the economic aspects before investing. However, by not explicitly linking ESG and economic criteria, attractive investments are often misjudged and not implemented. For example, investments that only show their value in the longer term or indirectly influence value by achieving a higher retention rate among incumbent tenants, reducing or eliminating friction costs. A product–service system (PSS) refers to a market proposition (business model) that builds on a product’s traditional functionality by incorporating additional services. Although services are already offered, the PSS function is to link the service to a product. The service thereby supports the operation of the product and generates additional benefits. It encompasses the integrated solutions of products and services to satisfy customers' needs and generate maximum value. According to Sutanto et al., a PSS is designed to focus on sustainability characterized in three dimensions. 1. The economic dimension 2. The environmental dimension 3. The social dimension When discussing sustainability in this thesis, we use the criteria listed above related to socially responsible investments. The link between PSS and ESG is that a PSS focuses on creating a sustainable system, and ESG makes sustainability more visible to investors. Therefore, when PSS are recognized and implemented in buildings, they must be evaluated using ESG analysis methods. Product-Service Systems (PSS) try to find a way to offer services on top of a product. The product is essentially secondary to the result that is delivered from the services. For example, the modem (product) that a cable company provides will be of secondary importance to the connectivity (service). Alternatively, it will be less critical how heat is made (product) than the intended set point is achieved in the building. PSSs transform the supply of products into services. In doing so, the responsibility shifts from delivering a product (once only) to continuous service delivery. Therefore, it is in the best interest of the service provider to deliver the outcome of the service as efficiently (read: lowest cost) as possible. A direct consequence of this is that the service provider will want to use the product as efficiently as possible and as long as possible to reduce his costs. Therefore, the supplier will also want to recover and maximize the reuse of his product based on the same rationale. A positive impact on the environment and the used raw materials is thus to be expected. The whole process of servitization (transforming products into services) in real estate will positively impact the Economic, Environmental and Social factors. Therefore, demonstrating this proposition is the main objective of this thesis. Smart PSS is the same idea as Product-Service systems but in which the digitization of the services plays a key role. It will be shown that by digitizing services, a broader range can be offered. It will be demonstrated that products that provide services at the building level can, through their interconnectedness, also provide services to external systems (e.g. electricity grid, urban planning, mobility, ...). At the same time, digitizing the products and services will also underpin trust in the systems and allow for proper remuneration. In this PhD, different standard systems in a building, such as the reservation system, the water heater, or the fire detection system, are equipped with additional services. A PSS is often specifically designed to focus on economic, social, and environmental dimensions. These dimensions correspond to the investor’s examination as part of the ESG analysis before investing. As the PSS is often specifically designed to integrate sustainability, there is a close link between the sustainability performance of the PSS and the ESG criteria evaluated by the investor. Throughout the work, the owner is considered to be the user of the building. It is not the case that only an owner-user can generate cash flow. In essence, if they have sufficient rights to the underlying product, any building user can activate services that generate cash flow. In today's market, it is logical that this is viewed in the owner-user context as they will usually choose the products to be installed in larger technical installations. They may have previously used a PSS or choose to move to one. However, a building’s tenant could choose to lease out their meeting rooms if they are not contractually prohibited from doing so since, in practice, contracts have begun to prohibit certain services. For example, rental contracts that actively prohibit renting out a property through platforms such as Airbnb. Thus, the user’s function could potentially impact how the PSS is designed. This work does not explicitly explore the impact of this aspect. The owner-user is assumed throughout this manuscript. The second chapter describes the state of affairs concerning PSSs in a broad framework evolving towards focusing on the real estate sector. After which, in the second chapter, ESG and the link to real estate and how smart real estate (smart buildings) is missing from this evaluation are discussed in more detail. Chapter 3 shows from a fire alarm system, which was extended with an evacuation support system, the usefulness, and the risk of data. Further work was done to demonstrate the added value in terms of Economic, Environmental and Social factors of standard installations in buildings. In Chapter 4, a simple sanitary hot water boiler is extended with a service that allows controlling this boiler according to the status of the electricity grid (surplus or shortage of energy). The supply and demand of energy on the power grid must be equal at all times. By equipping a classic water heater (product) with additional intelligence (service), it becomes possible to adjust the energy use to the grid's needs. The grid operators are prepared to pay for this. This payment can be linked to different energy markets (long term market, spot market, ...). This study looked at the fee that would have to be paid when the adjustment of the energy use can be made instantaneously so that the fee must be settled according to the prices on the imbalance market. In chapter 5, we look at the impact of the service to rent out free spaces as co-working places on a broad market (external to the building), compared to a regular reservation system. By renting out unused workplaces on a broad market, the utilization of the existing patrimony will be higher. The demand for new square meters with the same function will decrease as the supply-demand curve changes, and so will the price. This makes it less interesting to build new buildings. Less construction of new buildings will result in fewer resources being used, which will positively affect the environment. In addition, fewer new buildings with an office function will leave more space for buildings with another function. Also, the city's infrastructure will be less burdened (roads, sewerage, electricity grid,...). In The Hague, the decreasing need for new square meters of office buildings can lead to more space for affordable housing, for which the city has a great need. Chapter 6 will frame the valuation of service as a real options method that gives an impetus to a general valuation methodology to value the flexibility that Smart PSS inherently has. Finally, this thesis demonstrates that (smart) PSSs impact real estate profitability, while positively influencing environmental and social factors. Further research and the limitations of the studies conducted are documented. This PhD concludes that Product-Service systems should break the silos between different stakeholders, resulting in a lower total cost of ownership of buildings in the longer term. This can only be achieved if the valuation of Product-Service systems is done correctly and is recognized by every stakeholder in the real estate process. |
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Most recent IF: NA |
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UA @ admin @ c:irua:183415 |
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6912 |
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Author |
Saviuc, I. |
Title |
Assessment of electric residential microgrids in the EU context : role of energy storage, interactions with the main grid, and policy scenarios |
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Doctoral thesis |
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2021 |
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158 p. |
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Doctoral thesis; Engineering Management (ENM) |
Abstract |
As decentralized electricity generation plays an important role in the reform of the energy system in the EU, electric residential microgrids merit an assessment of their position and potential. The work on this dissertation focuses on the synergy between the development of microgrids that are powered by PV panels, and the adoption of energy storage, with the aim to identify shortcomings and propose solutions. Techno-economic assessment indicates that, for a microgrid that aims to maximize its self-consumption, the electricity pricing mechanisms that are current practice across the EU are detrimental to the economic viability of using energy storage. Case studies and simulations in Belgium, Greece, Denmark, Italy, Finland, Spain and Germany show conclusively how existing tariff structures (Net-Metering, Time-of-Use, Feed-in Tariff, with or without the option of a Capacity tariff) are suitable for stimulating renewable generation, but not storage. Another underlying reason that affects the economic viability of a residential microgrid in the current context relates to the technology losses, which cannot be compensated by electricity pricing mechanisms. Having established the need for a different approach in order to improve the economic viability of microgrids with storage, this work investigated whether a form of direct support to the microgrid operator can be envisioned. A cost-benefit analysis revealed that the benefits coming from decentralized energy generation toward the main electricity grid can be compared with the cost of including and operating energy storage, and therefore a direct support from the network operator and the public can be justified in order to attain the economic viability of a microgrid with storage. This way, the electricity network can benefit from an increased number of flexible, enriched microgrids within the system, the microgrid operators are incentivized to include energy storage, and the society contributes towards a sturdier energy supply with more engaged prosumers and less polluting emissions. Entrepreneurial diversity: a career motives’ perspective – Ilse D |
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UA @ admin @ c:irua:177112 |
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6915 |
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Berihun, D.; Van Passel, S. |
Title |
Climate variability and macroeconomic output in Ethiopia : the analysis of nexus and impact via asymmetric autoregressive distributive lag cointegration method |
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A1 Journal article |
Year |
2021 |
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Environment, development and sustainability |
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A1 Journal article; Engineering sciences. Technology; Engineering Management (ENM) |
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Ethiopia showed a rapid, yet, a none resilient economic growth much threatened by climate variability. In Ethiopia, the adverse effects of climate variability are stipulated among the significant factors constraining its economic development. There are relatively few studies about the adverse effects of climate variability on the Ethiopian macroeconomy. In this context, little is known about the exact effects of the ongoing climate variability on Ethiopian macroeconomic growth. This study intends to examine whether climate variability factors, for instance rainfall and temperature, have an effect on the macroeconomic output of Ethiopia. An asymmetric autoregressive distributive lag cointegration method is used to investigate time-series data for the years 1950-2014. Diagnostic tests show the relevance of the applied method and robustness of our results. The study finds climate variability affects Ethiopia's economic growth in the long run. Rainfall and temperature fluctuation induce significant negative impacts. A percentage annual temperature variability for instance decreases the Ethiopian annual gross domestic yield (GDP) up to 4.5 percent. In the short run, climate variability particularly rainfall and temperature changes also have a profound effect on Ethiopia's economic output. Within such confirmed climate change impacts, Ethiopia should carry out more on adapting and mitigating the impacts as it is presented on its climate-resilient economic growth policies and strategies. In spite of the policy contribution of the results, the study will motivate further research and will also serve as a benchmark for the coming Ethiopian studies. |
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000670722100001 |
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2021-07-07 |
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1387-585x |
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UA library record; WoS full record; WoS citing articles |
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OpenAccess |
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Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:179837 |
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6917 |
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Author |
Esguerra, J.L. |
Title |
Developing strategies for improved economic performance and reduced climate impact of landfill mining in Europe |
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Doctoral thesis |
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2021 |
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xiv, 99 p. |
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Doctoral thesis; Economics; Engineering Management (ENM) |
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Landfill mining refers to the re-circulation of resources from the previously deposited wastes–integrating resource recovery with traditional site remediation. Several resources that can be recovered include scrap metals, combustibles, and inert materials. In addition, land can be recovered or landfill void space can be liberated for future wastes. At present, landfill mining is still an emerging concept with few project implementations. Consequently, the assessments of its economic and climate implications are case study-specific, limiting the understanding of its potential in a wider geographical scope. This thesis aims to assess the economic performance and climate impact of landfill mining in Europe towards the development of sound strategies for implementation. Different project setups are assessed in relation to varying factors at the site level such as waste composition and landfill settings, and at the system level such as policy and market conditions and background material and energy. In doing so, a factor-based method is developed and applied to generate multiple scenarios (531, 441 scenarios per project setup) and determine the underlying important factors and their interrelations that drive the results. Such understanding is used to develop and discuss strategies for improvement by addressing relevant questions for specific stakeholders, including project investors (i.e., which landfill sites to prioritize?), landfill mining practitioners (i.e., how to set up such projects?), and policymakers (i.e., which policy instruments can effectively support such projects?). Results show that landfill mining is preferable in terms of climate than economy. Possible improvements are shown by internalizing thermal treatment of combustibles and extending fines residue utilization as construction aggregates. In relation to the choice of project setups, preferable site and system-level conditions are identified in general but it is also discussed that the plausibility of finding such conditions may be difficult at present. This steers the development of more tailored strategies on what can be done now by the landfill practitioners in terms of setting up projects under current policy and market conditions in specific regions, or what can be done by the policymakers in terms of implementing various policy instruments that can drive such changes at the system level. Through this thesis, the future of landfill mining research is guided towards addressing key challenges and potential solutions for improvement. Furthermore, this thesis highlights the role of assessment as a tool for learning and guiding the development of emerging concepts such as landfill mining. |
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978-91-7929-056-6 |
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Most recent IF: NA |
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UA @ admin @ c:irua:183155 |
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6920 |
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Chekol Zewdie, M. |
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How irrigation water impacts Ethiopian agriculture : an applied economics study |
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Doctoral thesis |
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2021 |
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xiv, 152 p. |
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Doctoral thesis; Economics; Engineering Management (ENM) |
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In recent decades, as crop production has increased in many areas where irrigation projects have been implemented, the global agricultural development community has promoted irrigation investments. However, due to the disappointing performance of irrigation farming in developing countries, irrigation intervention in Africa South of the Sahara including Ethiopia is an issue of debate. Moreover, several gaps exist in the Ethiopian irrigation farming literature. For instance, evidence about the direct and indirect effects of irrigation water on agriculture is not well documented. The irrigation farming literature has not disentangled the indirect effects of having access to irrigation water from the direct effect and the indirect effects have been underrepresented. Furthermore, most previous studies have applied either a quantitative or qualitative approach and have relied only on revealed data as main type of methodology, making studies that combine qualitative and quantitative research and that use both stated and revealed data underrepresented. In this study, different approaches have been applied to investigate how irrigation water impacts Ethiopia agriculture with special attention being given to disentangling the direct and indirect effects of irrigation water on Ethiopian agriculture. Using a structural equation model, a stochastic production frontier approach, and a discrete choice experiment, I drew evidence regarding the direct and indirect effects of irrigation water on crop revenue of smallholder farmers, the technical efficiency of irrigation user farmers, and the farmers’ willingness to pay to improve poor irrigation schemes from field observations, semi-structured interviews and focus group discussions with farmers, and key informant interviews with the local agricultural agents from the Koga and Fogera Districts of Amhara Region Ethiopia. The results indicate that irrigation water in general has both direct and indirect positive effects on agriculture, and the indirect effect is mediated by both improved farm inputs and the type of crops produced. The results also show that – due to poor extension services and backward agronomic practices, the mean technical efficiency of farmers in Ethiopia is very low, and that large-scale irrigation users are less technically efficient than small-scale irrigation users. Moreover, the results show that improving irrigation schemes shifts the frontier up, and smallholder farmers are strongly willing to contribute financially to the maintenance costs of irrigation schemes. The results offer relevant lessons for policymakers that providing irrigation water supply must be embedded in a comprehensive support package including access to extension services, improved input supply, and access to stable markets. |
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978-90-5728-700-8 |
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UA @ admin @ c:irua:180816 |
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6928 |
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De Weerdt, L. |
Title |
An inquiry into the market acceptance of circular plastics |
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Doctoral thesis |
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2021 |
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xii, 154 p. |
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Doctoral thesis; Engineering Management (ENM) |
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Closing material loops and reducing resource extraction is considered to be the foundation of the circular economy that delivers environmental gains. Today, certain materials with large environmental impacts, such as plastics, are placed high on the circularity agenda. In this thesis, the market acceptance of circular plastics is analyzed. Firstly, the current – mostly linear – market for plastics in the European Union is analyzed. We find that market failure and uncertainties lead to postponed and scaled down private investments in recycling facilities for plastics. As a consequence, we conclude the failing and uncertain market needs government intervention. Secondly, potential government interventions that alleviate the market failure and reduce the present uncertainties are analyzed. Government intervention can be either incentive-based or regulatory-based. The Flemish government already acts as an incentivizer. For more than two decades already, a tax is levied on the incineration of plastic waste. We find that this tax reduces industrial plastic waste generation, but fails to elicit investments in recycling facilities. Regulatory-based policies are expected to gain in importance in the pursuit of a circular economy. Indeed, in the European Commission’s latest circularity action plan, a policy to mandate the use of recycled plastics is signaled. Mandating the use of recycled plastics can enable the circularity of plastics effectively. However, it would also generate a shock wave on the market, especially because, i.a. the implementation time of such a policy is uncertain. We investigate how firms can invest optimally in the use of recycled plastics under the presence of policy uncertainty. We conclude that the European market will be able to successfully adopt circular plastics. However, stimulating policies, both incentive-based and regulatory-based, turn out to be essential in this adoption process. Therefore, there will be a need for a combination of policies in order to prevent the incessant mass single-use consumption of plastics, which harms the environment. |
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Most recent IF: NA |
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UA @ admin @ c:irua:178913 |
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6930 |
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Saviuc, I.; Van Passel, S.; Peremans, H. |
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Integrating PV+battery residential microgrids in distribution networks : how is the point of common coupling agreed upon? |
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H1 Book chapter |
Year |
2020 |
Publication |
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Abbreviated Journal |
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Volume ![sorted by Volume (numeric) field, ascending order (up)](img/sort_asc.gif) |
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Issue |
|
Pages |
150-164 |
Keywords |
H1 Book chapter; Economics; Engineering sciences. Technology; Engineering Management (ENM) |
Abstract |
The anticipated development of decentralized electricity generation is expected to strengthen the opportunities of prosumers in the residential areas of cities, in line with the predicted establishment of renewable energy generation and storage. Based on academic research and on successful case studies, the opportunity for residential prosumers to organize in microgrids emerges as a viable and promising solution. This paper focuses on microgrids that are planned to generate electricity with a PV unit and use a shared storage system, and that opt to have a connection with the main grid. However, the point of common coupling needs to be agreed first between the microgrid operator and the network operator, and this agreement is determined by several factors and conditions beyond the basic technical and regulatory requirements. A survey of academic literature on the determinant factors for such an agreement exposes the fact that current research either focuses on the integration of individual prosumers in the main grid, or regards the point of common coupling as a given component of microgrids. We argue that neither of the two approaches is helpful in the case of microgrids vs. main grid, seeing as the agreement is not self-evident under just any circumstances, nor can the microgrid be equated to a single, large prosumer. Therefore this short paper compiles a set of determinant factors for the microgrid integration, as they emerge from academic literature, with the aim to document further research needs and support the discussion on microgrid integration. |
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Wos |
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Publication Date |
2020-04-08 |
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Series Title |
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Abbreviated Series Title |
Sustainable Energy for Smart Cities : First EAI International Conference, SESC 2019, Braga, Portugal, December 4–6, 2019: proceedings |
Series Volume |
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Series Issue |
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Edition |
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ISSN |
|
ISBN |
978-3-030-45693-1 |
Additional Links |
UA library record |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:168515 |
Serial |
6932 |
Permanent link to this record |
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|
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Author |
Vicca, S.; Crabbé, A.; Van Passel, S. |
Title |
Is het coronavirus goed nieuws voor het klimaat? = Is the coronavirus good news for the climate? |
Type |
Newspaper/Magazine/blog article |
Year |
2020 |
Publication |
globalchangeecology.blog |
Abbreviated Journal |
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Volume ![sorted by Volume (numeric) field, ascending order (up)](img/sort_asc.gif) |
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Issue |
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Pages |
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Keywords |
Newspaper/Magazine/blog article; Sociology; Economics; Engineering Management (ENM); Plant and Ecosystems (PLECO) – Ecology in a time of change; Centre for Research on Environmental and Social Change |
Abstract |
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https://www.scientists4climate.be/is-the-coronavirus-good-news-for-the-climate/ |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
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ISBN |
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Additional Links |
UA library record; https://www.scientists4climate.be/is-the-coronavirus-good-news-for-the-climate/; https://globalchangeecology.blog/2020/04/03/is-het-coronavirus-goed-nieuws-voor-het-klimaat/ |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:168299 |
Serial |
6934 |
Permanent link to this record |
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|
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Author |
Einhäupl, P. |
Title |
Landfill mining : implementing the missing link to a circular economy: an evaluation of the societal sustainability |
Type |
Doctoral thesis |
Year |
2021 |
Publication |
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Abbreviated Journal |
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Volume ![sorted by Volume (numeric) field, ascending order (up)](img/sort_asc.gif) |
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Issue |
|
Pages |
xxiii, 216 p. |
Keywords |
Doctoral thesis; Economics; Engineering sciences. Technology; Engineering Management (ENM) |
Abstract |
One of the main objectives of implementing a circular economy system is the reuse and recycling of resources. Closing material cycles and renewable-based electricity and fuel production are essential to such systems. To achieve a high degree of circularity, waste streams have to be rethought and integrated from a cradle-to-grave to a cradle-to-cradle approach. However, today’s circular economy strategies mostly focus on current waste streams, while past waste streams, buried in landfills, could play an important role when recovering resources and energy. Hence, a well-thought-out circular economy strategy should include the re-integration of past waste streams. A grave-to-cradle approach is needed. Landfill mining (LFM), i.e. the excavation and processing of formerly buried waste to energy and materials, aims at utilizing these past waste streams. Doing so could bear potential economic, environmental, and societal burdens and benefits. Originating from landfill remediation projects, landfill mining has been further developed towards resource recovery. Today, using up-to-date technologies and following the most stringent environmental and social criteria, the concept is also known as enhanced landfill mining (ELFM). Throughout the relevant scientific literature, most attention is given to advances in technological development for (E)LFM, as well as its techno-economic and environmental assessment. Societal assessments of LFM projects are rare and treat societal impacts only selectively or from unilateral societal perspectives. If stakeholders are included in societal (E)LFM assessments, only industrial actors, like landfill operators, and governmental actors are asked to participate. A holistic stakeholder assessment for (E)LFM is missing. Moreover, the diverse societal impacts – ranging from socio-environmental benefits through the mitigation of health risks, over socio-economic benefits through land reclamation, and social benefits through community engagement, for example – are either only studied selectively or evaluated as one, entangling various societal effects. A holistic and specific assessment of societal factors affecting (E)LFM implementation is also missing. This thesis uses an anticipatory approach to tackle these challenges. This approach aims to integrate stakeholder values and include uncertainty through the use of multiple social perspectives and prospective modeling tools. In-depth interviews were conducted to develop a typology of (E)LFM stakeholders and to elicit the most important stakeholder needs. Stakeholders were selected along an extended quadruple helix framework, including industrial, institutional, scientific, and community actors. Furthermore, using system dynamics tools, namely causal loop diagrams, societal systems of (E)LFM could be visualized and analyzed. Finally, a discrete choice experiment was conducted to evaluate a set of societal factors representing the conversion of a landfill into a public park for recreational use. The in-depth interviews included landfill operators, technology providers and incubators, local governments and governmental institutions, as well as researchers and community members. To structure the diverse perspectives of stakeholders on (E)LFM, five stakeholder archetypes were developed: The Entrepreneur, the Engaged Citizen, the Visionary, the Technology Enthusiast, and the Skeptic. The archetypes capture important characteristics and opinions approaching (E)LFM implementation. They differ in risk perceptions, knowledge base, influence on (E)LFM’s systemic and project implementation, and their main concerns and motivations. Furthermore, 18 stakeholder needs were derived from the interviews. This includes societal, environmental, regulatory, and techno-economic needs. The needs are put in relation to the affected stakeholders and sustainability dimensions. Uncertainties that could potentially be reduced through the fulfillment of each need are qualitatively assessed. Quantitatively, stakeholders were focusing on societal, regulatory, and techno-economic needs, whereas qualitative emphasis was given to environmental needs, especially the avoidance of impacts from primary resource production. When meeting stakeholder needs fairly, intra- and inter-dimensional trade-offs have to be considered as different perspectives can lead to different and sometimes contradicting implications for (E)LFM implementation. To conceptualize societal systems of (E)LFM, causal loop diagrams were developed following system dynamics methodology. The visualizations show how (E)LFM is embedded in its societal context. Variables comprising the societal impact were analyzed, and mechanisms affecting the public project acceptance and the market acceptance of (E)LFM products worked out. Leverage points were identified, helping (E)LFM practitioners and policymakers to minimize potential risks and maximize potential benefits. To these count technological choices, stakeholder involvement, the after-use, quality standards, and LFM regulation in general, amongst others. To disentangle and evaluate societal impacts of (E)LFM, a discrete choice experiment was conducted deriving the utility of five distinct attributes: the size of a landfill, the project duration, job creation, disamenities, and climate impacts. To determine the willingness to pay, perform scenario analysis, and model policy simulations, a sixth attribute was added representing a cost factor for project implementation. Environmental considerations are most important to the sample, while project duration and disamenities also play a significant role. The scenario analysis and policy simulations show that taxing households for (E)LFM implementation is a viable option, especially for environmentally beneficial projects. Nonetheless, a favorable combination of the remaining attributes can compensate utility losses for environmentally questionable projects. As risks of classical landfill management practices are likely to grow with an updated evaluation of after-care periods lasting up to 100 years and more, positive effects of (E)LFM become even more noteworthy. Nonetheless, (E)LFM projects also pose potential risks like groundwater contamination or the reintroduction of hazardous materials. If executed poorly, (E)LFM projects could potentially do more harm than good. A mix of policy measures is recommended to push a major part of potential (E)LFM projects from being environmentally beneficial and economically inefficient to being societally, environmentally, and economically favorable. Overall, more research is necessary to integrate (E)LFM into circular economy strategies and build a sensible grave-to-cradle approach. |
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Wos |
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Publication Date |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
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ISBN |
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Additional Links |
UA library record |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:181007 |
Serial |
6935 |
Permanent link to this record |
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Author |
Annys, S.; Van Passel, S.; Dessein, J.; Ghebreyohannes, T.; Adgo, E.; Nyssen, J. |
Title |
Small-scale irrigation expansion along the dam-regulated Tekeze River in Northern Ethiopia |
Type |
A1 Journal article |
Year |
2020 |
Publication |
International Journal Of Water Resources Development |
Abbreviated Journal |
Int J Water Resour D |
Volume ![sorted by Volume (numeric) field, ascending order (up)](img/sort_asc.gif) |
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Issue |
|
Pages |
1-22 |
Keywords |
A1 Journal article; Engineering Management (ENM) |
Abstract |
Based on extensive field information, farmer-led small-scale irrigation systems along the dam-regulated Tekeze River is investigated and the likelihood of future irrigation expansion within the area with modelled potential is discussed, considering facilitating and hampering factors. Due to dam-induced hydrologic alterations, downstream socio-ecological systems have strongly transformed as the irrigated area has quadrupled and the post-dam potential for perennial crop cultivation has attracted numerous migrant investors to the area, inducing inequalities but also providing opportunities. Future dam construction should involve tailored policy interventions to facilitate irrigation expansion, while safeguarding equal and sustainable access to water and land. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000569995600001 |
Publication Date |
2020-09-16 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
0790-0627 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.1 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 3.1; 2020 IF: 2.088 |
Call Number |
UA @ admin @ c:irua:171952 |
Serial |
6943 |
Permanent link to this record |
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Author |
Admasu, W.F. |
Title |
Socioeconomic and environmental impact of expropriation of agricultural land for urbanisation in Ethiopia |
Type |
Doctoral thesis |
Year |
2021 |
Publication |
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Abbreviated Journal |
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Volume ![sorted by Volume (numeric) field, ascending order (up)](img/sort_asc.gif) |
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Issue |
|
Pages |
162 p. |
Keywords |
Doctoral thesis; Engineering Management (ENM) |
Abstract |
Globally, incorporation of agricultural lands into the urban boundary has been a common phenomenon. Governments use various alternatives to access the required land, including land expropriation procedures, which refers to the compulsorily taking of land from the landholders without their consent by paying compensation. In Ethiopia, the urban population is growing rapidly which resulted into an increase in the demand for urban land for housing construction, public services provision, and infrastructure developments. As the Ethiopian constitution prohibits sale of landholders, governments, at various levels, have been expropriating land from the surrounding farmers to meet the demand for urban land. The general objective of this thesis is to improve the understanding of the impacts of local land deals for urbanization on socioeconomics of farmers and the environment. The findings of this thesis revealed that there are gaps in the current practices of land expropriation for urban expansion that should be improved. The results showed that the compensation paid to the affected farmers is found to be economically inappropriate, i.e., not enough to restore the affected farmers’ livelihoods, in contrast with the land laws that allows a compensation amount that would put previous land users in a better or the same wellbeing as before the land expropriation. In addition, it is indicated that the land expropriation process does not take into account the value of ecosystem services, which are benefits obtain from the land, and important for the wellbeing of the society. We conclude that while land expropriation is an important tool to obtain land from the landholders when it is needed for public purposes, the practices in the study area show it is adversely affecting the socioeconomics of farmers and the environment. |
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Series Editor |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISBN |
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Additional Links |
UA library record |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:177909 |
Serial |
6944 |
Permanent link to this record |
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Author |
Van Schoubroeck, S. |
Title |
A techno-sustainability assessment framework : indicator selection and integrated method for sustainability analysis of biobased chemicals |
Type |
Doctoral thesis |
Year |
2020 |
Publication |
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Abbreviated Journal |
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Volume ![sorted by Volume (numeric) field, ascending order (up)](img/sort_asc.gif) |
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Issue |
|
Pages |
195 p. |
Keywords |
Doctoral thesis; Engineering Management (ENM) |
Abstract |
Biobased chemistry has gained interest and has the potential to tackle some of the sustainability challenges the chemical industry must endure. Sustainability impacts need to be evaluated and monitored to highlight the advantages and pitfalls of different biobased routes over the product life cycle. A better understanding of the potential sustainability of emerging biobased technologies and products is essential to guide additional research and further technology development. This PhD thesis aims to develop a framework for a techno-sustainability assessment (TSA), while accounting for technological as well as economic, environmental, and social aspects in an integrated approach. First, a review of the state-of-the-art sustainability indicators for biobased chemicals was conducted and a gap analysis was performed to identify indicator development needs. Afterwards, a Delphi study was performed to select sustainability indicators specifically for biobased chemical assessment and to reach consensus among experts on a prioritization of these indicators. Next, the selected sustainability indicators were quantified while integrating technological and country-specific data with environmental characterization factors, economic values and social data. Finally, a stochastic, hierarchical multi-criteria decision analysis (MCDA) integrates the independent techno-sustainability indicators expressed in different units, taking into account stochastic and flexible method options. The developed integrated TSA framework was applied to a case for which a production and harvesting plant of microalgae-based food colorants is assessed. The final aim of the integrated TSA is to compare the potential sustainability performance of different scenarios and to make better-informed choices between alternatives by evaluating environmental, economic and social sustainability impacts in one holistic model. Integrated TSA offers a novel framework where decision makers can assess sustainability already in early technology development stages by identifying potential hurdles and opportunities to guide R&D and make sustainable investment decisions. |
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Publication Date |
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Series Editor |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISBN |
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Additional Links |
UA library record |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:174826 |
Serial |
6947 |
Permanent link to this record |
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Author |
Bjørnåvold, A. |
Title |
Unlocking lock-in : accelerating socio-technical transitions to sustainability |
Type |
Doctoral thesis |
Year |
2021 |
Publication |
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Abbreviated Journal |
|
Volume ![sorted by Volume (numeric) field, ascending order (up)](img/sort_asc.gif) |
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Issue |
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Pages |
189 p. |
Keywords |
Doctoral thesis; Linguistics; Engineering Management (ENM) |
Abstract |
Achieving global sustainability goals will require cleaner and cheaper technologies. Public policy is central to achieving these goals and, in turn, ensuring a quicker pace of change. A major obstacle lies in the fact that technologies cannot be considered isolated entities: they are embedded in a powerful social context of cultural, organisational and institutional systems. This intertwining of different elements is referred to as a socio-technical system. This thesis discusses how socio-technical systems have, over time, allowed locked-in configurations to emerge, referring to a combination of systematic forces that perpetuate unsustainable infrastructures embedded in society. Such lock-ins can inhibit innovation and competitiveness of low-carbon and sustainable technologies, and this thesis looks to concrete solutions for unlocking them. Vital to this objective lies better understanding preferences, intentions, and behaviour of actors involved at each stage of technological development to improve public policy design. A discrete choice experiment – a quantitative non-market valuation method – was, therefore, a core method used to model preferences of key target groups. Target groups considered in the four components of the thesis include i) industry players, ii) policymakers, iii) farmers, and iv) the general public in Belgium, France, Germany, Italy and Spain. The thesis seeks to establish how both economic and regulatory instruments can be leveraged to overcome lock-in. One conclusion sees that implementing an efficient environmental tax regime – an economic instrument – requires balancing political feasibility and public acceptance considerations in line with tax and environmental policy. Results indicate that public acceptance for environmental taxation increases with earmarking. Another conclusion highlights the importance of taking behavioural and habitual considerations into account – both when considering policymakers’ investment decisions, and farmers’ decisions to adopting agro-ecological practices when responding to regulatory instruments. Overall, policy design should emphasise a more continuous and systemic approach to innovation and technology policy on the road to accelerating socio-technical transitions to sustainability. |
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Wos |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
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ISBN |
978-90-5728-692-6 |
Additional Links |
UA library record |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:179247 |
Serial |
6949 |
Permanent link to this record |
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Author |
Meng, X.; Chen, S.; Peng, H.; Bai, H.; Zhang, S.; Su, X.; Tan, G.; Van Tendeloo, G.; Sun, Z.; Zhang, Q.; Tang, X.; Wu, J. |
Title |
Ferroelectric engineering : enhanced thermoelectric performance by local structural heterogeneity |
Type |
A1 Journal article |
Year |
2022 |
Publication |
Science China : materials |
Abbreviated Journal |
Sci China Mater |
Volume ![sorted by Volume (numeric) field, ascending order (up)](img/sort_asc.gif) |
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Issue |
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Pages |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Although traditional ferroelectric materials are usually dielectric and nonconductive, GeTe is a typical ferroelectric semiconductor, possessing both ferroelectric and semiconducting properties. GeTe is also a widely studied thermoelectric material, whose performance has been optimized by doping with various elements. However, the impact of the ferroelectric domains on the thermoelectric properties remains unclear due to the difficulty to directly observe the ferroelectric domains and their evolutions under actual working conditions where the material is exposed to high temperatures and electric currents. Herein, based on in-situ investigations of the ferroelectric domains and domain walls in both pure and Sb-doped GeTe crystals, we have been able to analyze the dynamic evolution of the ferroelectric domains and domain walls, exposed to an electric field and temperature. Local structural heterogeneities and nano-sized ferroelectric domains are generated due to the interplay of the Sb3+ dopant and the Ge-vacancies, leading to the increased number of charged domain walls and a much improved thermoelectric performance. This work reveals the fundamental mechanism of ferroelectric thermoelectrics and provides insights into the decoupling of previously interdependent properties such as thermo-power and electrical conductivity. |
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Place of Publication |
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Wos |
000749973500001 |
Publication Date |
2022-02-02 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2095-8226; 2199-4501 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
8.1 |
Times cited |
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Open Access |
Not_Open_Access |
Notes |
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Approved |
Most recent IF: 8.1 |
Call Number |
UA @ admin @ c:irua:186429 |
Serial |
6959 |
Permanent link to this record |
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Author |
Lu, W.; Cui, W.; Zhao, W.; Lin, W.; Liu, C.; Van Tendeloo, G.; Sang, X.; Zhao, W.; Zhang, Q. |
Title |
In situ atomistic insight into magnetic metal diffusion across Bi0.5Sb1.5Te3 quintuple layers |
Type |
A1 Journal article |
Year |
2022 |
Publication |
Advanced Materials Interfaces |
Abbreviated Journal |
Adv Mater Interfaces |
Volume ![sorted by Volume (numeric) field, ascending order (up)](img/sort_asc.gif) |
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Issue |
|
Pages |
2102161 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Diffusion and occupancy of magnetic atoms in van der Waals (VDW) layered materials have significant impact on applications such as energy storage, thermoelectrics, catalysis, and topological phenomena. However, due to the weak VDW bonding, most research focus on in-plane diffusion within the VDW gap, while out-of-plane diffusion has rarely been reported. Here, to investigate out-of-plane diffusion in VDW-layered Bi2Te3-based alloys, a Ni/Bi0.5Sb1.5Te3 heterointerface is synthesized by depositing magnetic Ni metal on a mechanically exfoliated Bi0.5Sb1.5Te3 (0001) substrate. Diffusion of Ni atoms across the Bi0.5Sb1.5Te3 quintuple layers is directly observed at elevated temperatures using spherical-aberration-corrected scanning transmission electron microscopy (STEM). Density functional theory calculations demonstrate that the diffusion energy barrier of Ni atoms is only 0.31-0.45 eV when they diffuse through Te-3(Bi, Sb)(3) octahedron chains. Atomic-resolution in situ STEM reveals that the distortion of the Te-3(Bi, Sb)(3) octahedron, induced by the Ni occupancy, drives the formation of coherent NiM (M = Bi, Sb, Te) at the heterointerfaces. This work can lead to new strategies to design novel thermoelectric and topological materials by introducing magnetic dopants to VDW-layered materials. |
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Wos |
000751742300001 |
Publication Date |
2022-02-07 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
2196-7350 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
5.4 |
Times cited |
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Open Access |
Not_Open_Access |
Notes |
|
Approved |
Most recent IF: 5.4 |
Call Number |
UA @ admin @ c:irua:186421 |
Serial |
6960 |
Permanent link to this record |