[dipl] Perustieteiden korkeakoulu / SCI

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Aeronautics and Eco-design
(2020-08-18) Tempelaere, Matthieu
Perustieteiden korkeakoulu | Master's thesis
This master thesis report aims to introduce the reader to the basis of the eco-design in aeronautics. In this small guide the reader will understand from where the engineers went through and what the perspectives for this industry are. In order that the largest possible number of people can benefit from this relationship, the basic notions of mechanics, thermodynamics and materials will be developed. Then we will discuss and see how to improve the environmental impact of this industry, which is considered to be polluting.
Application and evaluation of two commercial softwares in the simulation of ultrasonic-based non- destructive testing of a welded component made of austenitic stainless steel
(2021-10-19) Gerlier, Laurine
Perustieteiden korkeakoulu | Master's thesis
CIVA and Athena 2D are the two main codes employed for the simulation of ultrasonic non-destructive testing. CIVA is a 3D semi-analytical model which reliability has been widely demonstrated through various validation campaigns. Athena 2D is a 2D finite element code, which has shown high accuracy in 2D complex configurations. A coupled model, called CIVA-Athena 2D, has been implemented in CIVA software in order to combine the advantages of each. CIVA and CIVA-Athena 2D have been developed on the basis of some assumptions, which consequently leads to limitation in the domain of application. These assumptions and validation ranges of both simulation tools are reviewed. CIVA- Athena 2D appears to be particularly recommended for typical limitation cases of CIVA, such as small defects and complex fields. The reproduction of the austenitic stainless steel weld’s anisotropic and heterogeneous structure is particularly difficult in modelling, as well as the understanding of the various phenomena occurring in such a material. CIVA and CIVA-Athena 2D simulations, combined with the Ogilvy model for the description of the weld, are conducted in order to confirm the origin of echoes detected on site during the examination of a set-in branch pipe. The predictions allow to decide on the spurious character of theses echoes and corroborate that the propagation of the beam through the weld causes ultrasound disturbances. Moreover, CIVA and CIVA- Athena 2D both provide satisfying results compared to experimental ones.
Beyond financial metrics, the place and role of technical and other additional due diligence in the process of Mergers & Acquisitions transactions. Case study in the Engineering Services Industry.
(2020-08-18) Noell, Pauline
Perustieteiden korkeakoulu | Master's thesis
This paper aims at complementing the literature on Mergers & Acquisitions (M&A) with a case study to provide the lecturer with a full insight on the diversity of the challenges inherent to M&A transactions. Especially, a strong emphasis will be made on extra-financial analysis of the target. Indeed, a M&A process always includes a very formal and standardized financial analysis of the target, called the Financial Due Diligences, very often including also a similar Tax & Legal Due Diligences process. However, the collection and analysis of other information relative to the business and its specificities are much less standardized. As regards to the technical capabilities of the target or economic and operational considerations, the level of information available to the purchaser might be significantly variable from an acquisition to another, depending on the availability of the info first, but also on the quality of the analysis of them. This case study will provide concrete examples of what additional analysis to the financial ones can be performed on the target and its environment. It will be then discussed how crucial they might be in the decision-making process of pursuing with the acquisition or not. The discussion will be extended to the place that take each of those analysis (financial and extra-financial ones) in the valuation of the target and the consistency of current valuation methods as regard to the importance of each element.
Characterization of surface wetting properties using Scanning Droplet Adhesion Microscopy
(2021-08-24) Sahaoui, Mohamed
Perustieteiden korkeakoulu | Master's thesis
Characterization of surface wetting uniformity in hydrophobic tubes using ferrofluid droplets
(2019-08-20) Lefranc, Vivien
Perustieteiden korkeakoulu | Master's thesis
Hydrophobic surfaces, or water repellent surfaces, have interesting properties for applications on selfcleaning, anti-icing, antifogging and fluid drag reduction. To develop more efficient surfaces, proper characterization methods need to be developed as the current methods available are not sufficient. In this thesis, the theoretical background behind wetting phenomena on hydrophobic surfaces and various techniques for characterizing wetting properties are presented. Furthermore, a new characterization technique applied to hollow, non planar surfaces and more specifically to transparent tubes is proposed. This technique measures wetting inhomogeneities using magnetically controlled water-like droplets over the entire length of the samples. This technique can measure the retentive force, a dissipative force related to the contact angle hysteresis at the three-phase contact line. This technique is used to see differences in wetting properties using reference tubes and their annealed counterparts using two different ferrofluids. As a non-destructive and quantitative characterization method, this technique could readily be used for quality control in academia and industries.
Designing a photovoltaic power plant: the key issue for industrial clients in the case of self-consumption or grid injection project
(2020-10-20) Bolo, Quentin
Perustieteiden korkeakoulu | Master's thesis
With global environmental awareness and European environmental policy, industrial companies are looking for solutions to prove their commitment without losing money. SunMind, a French photovoltaic developer, offers self-consumption or grid injection projects with third-party investment through On-site PPAs or land leases. The profitability of these two types of projects depends on a proper design of the PV plant according to the client’s requirements. However, what are the different components of a photovoltaic power plant? What are the main steps in designing a PV power plant in the case of self-consumption or grid injection projects for industrial clients? How to choose the power to be installed in the case of both projects depending on the client? This thesis presents the self-consumption and grid injection models used by SunMind, the basics of the photovoltaic field, analyses the different components of a PV power plant, discusses the two software, SketchUp Skelion and PVSyst, used during this thesis and proposes a method for designing and sizing a photovoltaic plant according to the client, focusing on key steps such as the analysis of the client’s consumption and the solar potential of the client’s site.
Developing the Scanning Droplet Tribometer
(2021-10-19) Vieillescazes-Delrieu, Tanguy
Perustieteiden korkeakoulu | Master's thesis
This thesis reviews the needs of the research and industry for surface wetting characterization, as well as the different wetting characterization methods available. The thesis puts in evidence the arising need for a method of fast surface wetting scanning. The Scanning Droplet Tribometer (SDT) offers a solution to this need. This instrument scans the friction and adhesion forces of a magnetically controlled water-like droplet on a surface. However, the original design of the SDT requires further development. The sources of errors are investigated, and we suggest improvements to the SDT, to make it more reliable and adapted to a wider range of samples.
Domain-specific Threat Modeling for Mobile Communication Systems
(2021-08-23) Chen, Hsin-Yi
Perustieteiden korkeakoulu | Master's thesis
As the attack surface and the number of incidents in mobile communication net- works increase, threat intelligence gathering and sharing among different parties becomes essential. There are many generic threat modeling frameworks for soft- ware and information system, but none of them is targeted for the telecommunication industry. A common conceptual framework and threat taxonomy is needed for communicating the threats between industry players or to form a high-level view of the state of security of a mobile network. Therefore, Nokia Bell Labs has developed the Bhadra framework, a conceptual framework for threat modeling in mobile communication systems. The goal of this thesis is to improve the Bhadra framework and explore its use cases. First, we developed a web tool to support the threat and attack modeling process with the framework. We modeled 60 attacks from literature with the tool. To improve the framework, we performed two iterations of framework refinement. First, we added some missing techniques found during the attack modeling process. Second, we conducted peer modeling and sought input from security experts. Based on the results, we added the Reconnaissance tactic to cover adversarial behavior before gaining an initial foothold, modified and reorganized the attacks techniques, and edited technique descriptions to provide clearer definitions and concrete examples. Additionally, we performed a graph-theoretic analysis of the 60 attack models to gain insights on the relative importance of the attack techniques, the diversity of the attack paths from initial access to impact, and common attack patterns. Moreover, we evaluated the usability of the tool and the reliability and usefulness of the refined framework. The study participants generally gave positive feedback about the usability of the tool and the framework. Furthermore, the participants are interested in integrating the framework or the tool into their work processes, including threat modeling, mitigation and prevention, anomaly detection and investigation, threat intelligence sharing, and security management.
Dynamic life cycle assessment to compare conventional and bio-based building construction impact on global warming
(2019) Zieger, Vladimir
Perustieteiden korkeakoulu | Master's thesis
In a context of climate emergency, storing temporarily carbon in biogenic construction materials seems a particularly attractive strategy to mitigate important building sector impact on global warming. Usually, environmental impacts are assessed using standard Life Cycle Assessment (LCA), a product-based method that gives notably the global warming potential (GWP). In LCA, all greenhouse gas emissions linked to the product are assumed to be released in the first year even if they are emitted at different times within the chosen time horizon. Their GWP is calculated at this time horizon, which is usually 100 years. Moreover, biogenic carbon is often excluded of the calculation assuming a balance between captured and emitted carbon. On the other hand, new global warming impact calculation methods such as dynamic LCA propose to include timing in the calculation and to assess the value of temporarily storing carbon in long-lived products such as building structures. The aim of this study was to investigate the impact of these hypotheses on the estimated GWP of building materials, by comparing the static and a dynamic LCA approach. Two types of exterior walls were compared: one made with conventional materials (concrete and glass wool), the other mostly composed of bio-based materials such as straw and timber. Several parameters are discussed in detail: the real lifespan of buildings in France, carbon storage by forests and annual crops, the time horizon used to calculate GWP, the different greenhouse gases emitted, the accuracy of CO2 equivalent as an indicator of global warming. Finally, the overall impact on the global warming of different building construction and renovation materials is estimated under different scenarios applied to the French context.
Eco-design
(2020-08-18) Melkebeke, Clément
Perustieteiden korkeakoulu | Master's thesis
Electrical and Electro-Optical Characterization of Ultra-Wide Band Gap Semiconductors Devices
(2021-08-24) Faure, Camille
Perustieteiden korkeakoulu | Master's thesis
Due to the increasing use of new energies and new ways of transportation, the electric grid requires novel power devices that allow energy to be saved. Among semiconductors, diamond is one of the promising materials that is well known to overpass the current silicon semiconductor due to its physical properties better suited for high power application. This paper aims to study and understand the electrically active defects present in recent diamond power devices, such as Schottky diodes or Metal Semiconductor Field Effect Transistors (MESFET). These defects can be created during the manufacturing steps and impact the electrical performances of the component. To characterize the potential defects present in the device, we mainly used two methods: Thermal Admittance Spectroscopy (TAS) and Deep Level Transient Spectroscopy (DLTS). Two components were studied by using the previous methods and other simple electrical measurements, a Schottky diode and a MESFET. Regarding the diode, the results showed no defects except boron with an activation energy of 0.34 eV and a capture cross section of 7×10-12 cm-2 determined by TAS. Concerning the transistor, DLTS and current-voltage measurements revealed a potential activation by light or thermal energy of the pn-junction between the channel and the 1b diamond substrate. Further investigations on the junction also indicated the presence of a conductive layer situated on the side of the sample, that could have affected the previous experiments. These results suggest that well-designed diamond components can contain only a few defects similarly to the diode. The results also demonstrate that the substrate-channel pn-junction or diamond growth on the side of the component can impact its functioning and should be considered when designing the device.
Environmental grading of materials as an eco-design tool
(2020-08-18) Bernardi, Louison
Perustieteiden korkeakoulu | Master's thesis
The main goal of this master thesis is to develop an Eco-design tool for the aeronautical sectors comparing the traditional aeronautical materials (aluminium vs carbon composite). This Eco-design tool assesses the environmental performance of materials into grades and those grades are implement in traditional design tool. The environmental grades are determined using a life cycle assessment (LCA) approach. The method used to answer those question is: i. performing an environmental assessment of the selected materials, ii. translating the environmental assessment into grades and iii. evaluating the LCA uncertainties of the obtained grade thanks to characterization and numerical simulations. First, the comparison of materials environmental impacts during the design process relies on environmental assessment of materials. This environmental assessment is performed using the LCA method and the LCA software GaBi. The scope on the LCA is limited to the manufacturing of the final materials from virgin and (if possible) secondary materials. The impact assessment methods used are ReCiPe 2016 and Environmental Footprint 2.0. The environmental assessment gives the environmental impacts on 16 impacts categories including acidification, human toxicity, climate change or energy resource. The raw results of the conducted LCA are not on an easy-accessible format and that is the reason why the LCA results are transformed into environmental grades. Thus, the impacts of a material are translated into grade by normalizing the environmental assessment results and a weighting method. The normalization allows to make the different impacts dimensionless and thus be able to combine the different impact into a grade. The weighting method provides weighting factors for each impact category and allows to obtain the final environmental grade. The weighting factors represent the importance of each impact category, these factors were determined by Castenalli (Castellani et al., 2016). Finally, the uncertainties are determined by applying standard deviation analysis to the critical parameters and Monte Carlo simulations.
Fabrication of biopolymer-based optical fibers for short-distance applications
(2021-12-14) Sanouillet, Alizée
Perustieteiden korkeakoulu | Master's thesis
The extraordinary ability of optical fibers to control and propagate light has sparked a revolution in modern high-capacity communication networks. Beyond data networks, the state-of-the-art glass and plastic optical fibers have also been studied for numerous biomedical applications, including laser surgery, optogenetics, phototherapy and biosensing. However, commercial optical fibers have several disadvantages due to their brittle nature, non-biocompatibility and non-degradability necessary for biomedical applications. Therefore, there is a need to develop optical fibers from biopolymers that are biocompatible and biodegradable. Because of their biocompatible nature, biopolymer optical fibers can remain in the human body for a long time without iliciting an immune response. Because of their biodegradable nature, surgical removal after their use is not necessary. This thesis aimed to identify critical parameters to fabricate and characterize biopolymer optical fibers using environmentally benign fiber spinning methods. Three types of biopolymers, viz., alginate, carboxymethylcellulose and methylcellulose, were used for fiber preparation. The hydrogels prepared from the biopolymers were used for fiber extrusion using either wet-spinning or dry-jet wet spinning. The fibers were ionically cross-linked using metal ions under ambient conditions. The resulting fibers were then optically characterized for their waveguiding properties using the cutback method. The optical characterization suggests that the alginates-based fibers are not suitable for waveguiding due to very little light propagation. Interestingly, carboxymethylcellulose fibers displayed very low optical loss. This is on par or better than biopolymer optical fibers reported in the literature. The results encourage to explore further the potential of naturally abundant and renewable biomaterials for short-distance optical fibers.
Fabrication of Polycaprolactone/nanocellulose composite based on Pickering emulsion template stabilized by lignin particles
(2020-10-20) Kimiaei, Erfan
Perustieteiden korkeakoulu | Master's thesis
Increasing the need for evolution of sustainable products has recently driven huge interest to develop biobased composites as eco-friendly alternatives for petroleum-based materials. Cellulose nanofibril (CNF) reinforced composites have extensively shown great potential in this field due to their high abundance, renewability, biodegradability, and superior mechanical properties. However, their hydrophilic nature induced incompatibility with many hydrophobic polymer matrixes that has limited their use. In the present work, lignin nanoparticles stabilized Pickering emulsion template was introduced for the first time to incorporation of CNF into the polymer matrix for developing nanocomposite materials. The obtained biobased composite films exhibited proper mechanical properties that demonstrate the high potential in many fields such as packaging and biomedical applications. Additionally, comprehensive literature survey will be presented in this work including, the introduction of lignocellulosic biomass and its constituents, lignin structure, most important methods for extraction of lignin from lignocellulosic biomass, transforming lignin into colloidal particles, and evaluating its high value-added applications.
Green hydrogen in the energy transition: a review.
(2021-08-24) Louvet, Louis
Perustieteiden korkeakoulu | Master's thesis
An unprecedented worldwide momentum is pushing forward the development of hydrogen since it is a fuel that can be synthesised using low-carbon sources. When the source is renewable energy, the hydrogen is referred to as ”green”. As such, it could have a key role in the fight against climate change and in the global reduction of greenhouse gases emissions. This paper is a literature-based review that aims to give an overview of the current situation regarding hydrogen: its current and future uses, its production routes and its related technical, environmental and economical challenges. It provides additional information about the situation in France and on the ways hydrogen can be produced from renewable electricity. Those production modes are then compared economically. From the economic analysis, it seems that it is not economically feasible to produce hydrogen only when prices are low (in periods of overproduction). Green hydrogen is also expected to become cost-competitive against the current fossilbased hydrogen by the 2030’s. The review concludes on two major comments. The first comment is the importance of remaining critical and remembering that every consumption leads to greenhouse gases emissions. Hence, hydrogen is only a very limited part of the answer to our current issues. The second comment is the importance to support the development of low-carbon hydrogen to reduce emissions in key sectors. While current production of fossil-based hydrogen represents around 2% of the global CO2 yearly emissions, this could be avoided by switching to green hydrogen. Furthermore, low-carbon hydrogen could also directly replace some fossil fuels further lowering CO2 emissions. For example, hydrogen is one of the only feasible solution to produce steel without requiring coke (currently accounting for around 7 % of CO2 emission). Therefore, the development of green hydrogen is required and it will have a major role in the energy transition of the 21st century.
How eco-design tools can be implemented in the product development process of a company: A case study on bicycle helmet
(2021-10-19) Clouard, Robin
Perustieteiden korkeakoulu | Master's thesis
This study was performed at the facility of Intersport France (Ile-de-France, 91), at the department of Sourcing, Quality and Development team. The purpose of this work is to evaluate the benefits of eco-design tools for large companies with important economic constraints, such as Intersport, and the types of products that can emerge from their use. To do so, I have described the general process of product development first and compared with the process of Intersport. It allowed me to understand how the eco-designing part can be implemented in the product development process. I, then, worked on the different sustainable initiatives implemented in the industry and more specifically at Intersport. After that, a set of different eco-design tools were selected due to different parameters of evaluation, to choose exploitable tools for a novice team. The choice of the product that would be developed was made on a bicycle helmet, because of its technicity and the use of plastic, which is a similar aspect of many of the other products developed by the SQD team. After having described the technical decomposition of the bicycle helmet, the use of two tools: the TRIZ contradiction matrix and the Life Cycle Assessment, allowed to find that the best compromise for an eco-designed helmet is a composite liner with EPS and cork. This product was already developed by another brand, expert in the industry of bicycle helmet, which confirmed the scalability of the project. Based on environmental criterion such as CO2 emission, this product was compared to carbon shell helmet and standard helmet, as they are the most representative helmets currently available on the market. Finally, the results of the tools were exposed to the SQD team, to see if the eco-design tools used can be transmitted and used by every product developer. The results were mitigated, since the use of the tools was not easy to understand enough to be used by everyone, but the environmental aspect was considered seriously.
HVDC Cables: Interface between two insulators subjected to an HVDC electrical voltage
(2020-10-20) Mourad, Maya
Perustieteiden korkeakoulu | Master's thesis
Implementation of circular economy practices into waste management of large-scale public areas (shopping centers or hotels)
(2021-08-24) Schandl, Albert
Perustieteiden korkeakoulu | Master's thesis
Improving the French GreenTech ecosystem to better support GreenTech startups
(2021-08-24) Dulin, Charlotte
Perustieteiden korkeakoulu | Master's thesis
Global warming and environmental issues foster the emergence of GreenTech startups. To promote their creation and support their growth, a wide variety of institutions exist. The diversity of actors in the French GreenTech ecosystem makes it difficult for startups to identify the most appropriate actor at each step of their development and for each one of their specific needs. Bpifrance, the public bank for innovation in France, wishes to know how to consolidate this ecosystem. This work aims at providing a clear vision of the GreenTech ecosystem in France, and at identifying potential lacks in the support to GreenTech startups. Based on prior literature and semi-structured interviews, the study examines how GreenTech startups are supported by the GreenTech ecosystem in France and how this support could be improved. Seven GreenTech startups and twelve GreenTech institutions from various sectors were interviewed. Results of the discussions reveal that GreenTech startups do not face any specific needs compared to other startups, but struggle to find appropriate assistance. Three reasons explain this situation: the opacity of the GreenTech ecosystem, insufficient interactions between actors of this ecosystem, and a lack of industrial R&D facilities. A mapping of the GreenTech institutions in France, and their role at each development stage of a startup, delivered at the end of this study, helps to bring some clarity to the ecosystem. To improve the ecosystem, several recommendations are also given. Bpifrance can support the French GreenTech ecosystem with the creation of a GreenTech community, by rewarding newly formed partnerships between actors of the ecosystem, and by sensitizing institutions to green technologies and their importance. GreenTech actors should formalize further their support to GreenTech startups in order to measure their impact & their efficiency and offer more industrial R&D platforms for startups to be able to scale more rapidly.
Influence of the addition of pigments in a silicone elastomer – Study of the mechanical properties
(2019-08-20) Fischer, Léa
Perustieteiden korkeakoulu | Master's thesis

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Browsing [dipl] Perustieteiden korkeakoulu / SCI by Degree programme/Major subject "Advanced Materials for Innovation and Sustainability"