Scientific direction Development of key enabling technologies
Transfer of knowledge to industry

PhD : selection by topics

Devellopment of the coercivity in TRFe12 alloys for permanent magnets with low rare earth content

Département des Technologies des NanoMatériaux (LITEN)

Laboratoire Matériaux Avancés et mise en forme

01-10-2019

SL-DRT-19-0606

sorana.luca@cea.fr

In a context of significant development of engines and generators based on permanent magnets (hybrid vehicles, wind turbines) and limited raw material resources, it is necessary to reduce the amount of rare earths (TR) present in the NdFeB magnets. The research of new compounds, containing less TR, which could replace the NdFeB permanent magnets while keeping the high magnetic performances of these magnets, is essential. We are currently seeing a renewed interest in the TRFe12 phases known since 1990, which have interesting intrinsic magnetic properties for permanent magnets: saturation magnetization and anisotropy field equal to or even larger than for Nd2Fe14B. However, the work carried out in the scientific community does not make possible to obtain sufficient coercivity to be able to replace the magnets in Nd2Fe14B. The goal of this PhD thesis is: (1) the development of the TRFe12 alloys manufacturing process and sintering conditions; and (2) understanding and developing the coercivity in TRFe12 magnets. The student will use the experimental means of the Poudr'Innov platform of CEA-LITEN as well as those present at the CNRS - Institut Néel for the manufacture of magnets. Magnetic characterizations will be performed using conventional resources (hysteresis measurement, magnetometer at different temperatures) possibly large instruments (ILL). The expected results are: (1) the synthesis of the anisotropic TRFe12 phase, (2) the realization of sintered magnets of TR-Fe12 type by conventional and / or SPS methods, and (3) the understanding of the mechanisms of coercivity in magnets with low TR content.

Resistant and resilient processor to fault attacks and side-channel attacks

Département Systèmes

Laboratoire Sécurité des Objets et des Systèmes Physiques

01-09-2019

SL-DRT-19-0608

olivier.savry@cea.fr

Crypto-processors are not the only ones that are sensitive to fault attacks and side-channel attacks, CPUs are also prone to those flaws. Unfortunately, their sensitivities to these threats are poorly known. The objective of this thesis will be to characterize the consequences of these faults and leaks. New horizontal-type side-channel attacks based on machine learning can be experimented to go back to the executed code. Based on this knowledge, the PhD student will implement a processor core on FPGA completely resistant to intentional faults and side-channel attacks. Fault countermeasures solutions are often based on redundancy (spatial and temporal redundancy, error detector and corrector code, ...) that only increase the leakage and therefore the vulnerability to side-channel attacks. This approach is innovative as it aims to resolve this dilemma. The detection of faults is not the only constraint to be taken into account, however, it will be necessary to ensure that the CPU is resilient and able to restart from a stable state as close as possible to the erroneous state.

DPACA (CTReg)

Autre

01-10-2019

SL-DRT-19-0617

javier.gil-quijano@cea.fr

The electricity market is governed by rules drawn up by the transmission system operator, with the assistance of the distribution system operators for certain parts, then approved by the Energy Regulatory Commission or the Minister in charge of energy. These rules describe the roles and responsibilities of the various actors involved in the balancing of the network, the energy and capacity exchange modalities between these actors as well as the financial penalties associated with the non-respect of certain constraints. These documents thus ensure the security of supply of our country, reconciling the freedom to trade with the technical constraints inherent to the product "electricity". The major feature of this product is that at every moment consumption must be strictly equal to production. Market rules are regularly updated, in particular to facilitate the integration of decentralized renewable production, to encourage consumer involvement in balancing mechanisms, all in line with European requirements. The proposed thesis aims at designing and validating IT tools to simulate the impact of possible regulatory developments on market players and on the balancing mechanisms of the electricity grid. These simulations will shed light on market players, grid operators, the regulator and public authorities.

3D Thermomechanical Modeling of Printed Circuit Boards

DLORR

01-09-2019

SL-DRT-19-0623

manuel.fendler@cea.fr

The digital transition is illustrated in the factory of the future by the instrumentation of tools and parts evolving in extremely harsh environments for the Internet of Things. In order to ensure an efficient and robust integration, the study proposed in the context of this thesis aims to acquire knowledge of design constraints, and to implement the modeling and simulation tools that allow the collaborative mechanical and electronical design of future intelligent industrial systems

Electronic packaging by cold spray metallic encapsulation

DLORR

01-09-2019

SL-DRT-19-0624

manuel.fendler@cea.fr

The digital transition is illustrated in the factory of the future by the instrumentation of tools and parts evolving in extremely harsh environments for the Internet of Things. One of the difficulties is to integrate wireless communicating functions inside metallic parts, in particular for purposes of traceability with RFID tags. Due to the difficulties associated with the delicate electromagnetic environment, there are no integration solutions in the state of the art. The aim of this study is to investigate the potentialities offered by the Cold Spray technique, by characterizing the beneficial effects of texture on the metal absorption properties thus implemented to encapsulate the electronic chip.

Tools and methods for securing a memory hierarchy against software side-channel attacks

Département Systèmes

Laboratoire Sécurité des Objets et des Systèmes Physiques

01-10-2019

SL-DRT-19-0625

thomas.hiscock@cea.fr

Nowadays, computing systems execute an important quantity of untrusted software and have to isolate them from other user-trusted applications. For such multi-applications environments, strong process isolation is mandatory for security. Indeed, it prevents malicious processes to read or modify data of legitimate ones. In practice, perfect isolation is very difficult to achieve. Indeed, virtual memory or virtualisation are usually not sufficient: processes still execute on the same hardware and share lots micro-architectural elements. The memory hierarchy, from first level of caches to random access memory (RAM) represents without doubts the most important part of hardware shared between different processes and hence represents a large surface of attack. This is illustrated by many examples like cache attacks, known for more than a decade, software-induced faults in DRAM (Rowhammer) or information leakage through the MMU. Even the famous Spectre and Meltdown attacks revealed in 2018 rely on caches to extract sensible information. Since most of these vulnerabilities are known for years, a large panel of ?vulnerability-specific? countermeasures is available. However, no single solution covers all these vulnerabilities and the interaction of these countermeasures is not really studied. The first objective of this thesis is to develop new tools (statistical and/or simulation based) to reason about the security of the memory management hardware as a whole. These tools will form a solid basis to compare existing countermeasures taken from the state-of-the-art and combine them efficiently. Finally, a key contribution of the thesis will be to propose, design and evaluate possible countermeasures to secure the memory hierarchy.

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