SOT-MRAM 300mm integration for low power and ultrafast embedded memories

We demonstrate for the first time full-scale integration of top-pinned perpendicular MTJ on 300 mm wafer using CMOS-compatible processes for spin-orbit torque (SOT)-MRAM architectures. We show that 62 nm devices with a W-based SOT underlayer have very large endurance (> 5x10^10), sub-ns switching time of 210 ps, and operate with power as low as 300 pJ.Comment: presented at VLSI2018 session C8-

Bi-directional series-parallel elastic actuator and overlap of the actuation layers

Several robotics applications require high torque-to-weight ratio and energy efficient actuators. Progress in that direction was made by introducing compliant elements into the actuation. A large variety of actuators were developed such as series elastic actuators (SEAs), variable stiffness actuators and parallel elastic actuators (PEAs). SEAs can reduce the peak power while PEAs can reduce the torque requirement on the motor. Nonetheless, these actuators still cannot meet performances close to humans. To combine both advantages, the series parallel elastic actuator (SPEA) was developed. The principle is inspired from biological muscles. Muscles are composed of motor units, placed in parallel, which are variably recruited as the required effort increases. This biological principle is exploited in the SPEA, where springs (layers), placed in parallel, can be recruited one by one. This recruitment is performed by an intermittent mechanism. This paper presents the development of a SPEA using the MACCEPA principle with a self-closing mechanism. This actuator can deliver a bi-directional output torque, variable stiffness and reduced friction. The load on the motor can also be reduced, leading to a lower power consumption. The variable recruitment of the parallel springs can also be tuned in order to further decrease the consumption of the actuator for a given task. First, an explanation of the concept and a brief description of the prior work done will be given. Next, the design and the model of one of the layers will be presented. The working principle of the full actuator will then be given. At the end of this paper, experiments showing the electric consumption of the actuator will display the advantage of the SPEA over an equivalent stiff actuator

Engineered Biomaterials to Enhance Stem Cell-Based Cardiac Tissue Engineering and Therapy

Cardiovascular disease is a leading cause of death worldwide. Since adult cardiac cells are limited in their proliferation, cardiac tissue with dead or damaged cardiac cells downstream of the occluded vessel does not regenerate after myocardial infarction. The cardiac tissue is then replaced with nonfunctional fibrotic scar tissue rather than new cardiac cells, which leaves the heart weak. The limited proliferation ability of host cardiac cells has motivated investigators to research the potential cardiac regenerative ability of stem cells. Considerable progress has been made in this endeavor. However, the optimum type of stem cells along with the most suitable matrix-material and cellular microenvironmental cues are yet to be identified or agreed upon. This review presents an overview of various types of biofunctional materials and biomaterial matrices, which in combination with stem cells, have shown promises for cardiac tissue replacement and reinforcement. Engineered biomaterials also have applications in cardiac tissue engineering, in which tissue constructs are developed in vitro by combining stem cells and biomaterial scaffolds for drug screening or eventual implantation. This review highlights the benefits of using biomaterials in conjunction with stem cells to repair damaged myocardium and give a brief description of the properties of these biomaterials that make them such valuable tools to the field.Anwarul Hasan acknowledges the startup grant and the University Research Board (URB) grant from American University of Beirut, Lebanon, and the National Council for Scientific Research (CNRS) grant, Lebanon, as well as the Farouk Jabre interdisciplinary research award. Arghya Paul acknowledges the University of Kansas New Faculty General Research Fund for support and assistance with this work. The authors also acknowledge an investigator grant provided by the Institutional Development Award (IDeA) from the National Institute of General Medical Sciences (NIGMS) of the NIH Award Number P20GM103638-04 (to A.P.). R.W. acknowledges the financial support from NIGMS (NIH, T32-GM008359) Biotechnology Predoctoral Research Training Program

The micromechanics of TRIP-assisted multiphase steels

The industrial interest for TRIP-assisted multiphase steels is now a fact. Indeed, major requirements of the automotive industry since a few years, concern weight reduction of vehicles in order to lower fuel consumption and limit the rejection of greenhouse gas. Moreover, constraining safety criteria are imposed to automotive body. Projects like the Ultra Light Steel Auto Body (ULSAB) project, demonstrate the possibility of reducing the weight of car bodies by 25% by using high performance steels as well as new forming and assembly techniques. The aim of this thesis is to characterise and to model the different mechanisms of plastic straining occurring in TRIP-assisted multiphase steels. This approach allows to understand and to predict the forming properties exhibited by these steels. By coupling different techniques such as nano-indentation, neutron diffraction and digital image correlation, it was possible to establish the in situ flow behaviour of the constitutive phases of several TRIP-assisted multiphase steels. Moreover, the dependence of the kinetics of the martensitic transformation on various imposed stress states has been ascertained. This micromechanical characterisation demonstrates that, more than any other materials, TRIP-assisted multiphase steels must be designed not only as a function of the desired application but also as a function of the peculiarities of the forming process necessary to achieve this application. Finally, all the experimental results constituted the input data necessary for the constitutive model predicting the mechanical behaviour of TRIP-assisted steels that takes into account the transformation of metastable austenite. Thanks to this model, it has been possible to assess the most important features of the complex mechanical behaviour of the TRIP-aided steels.Doctorat en sciences appliquées (FSA 3)--UCL, 200

On the conformation of a segment of carp hemoglobin

SCOPUS: no.jinfo:eu-repo/semantics/publishe

Vibration isolation and control of heavy extended objects

peer reviewe

Vibration isolation and control of heavy extended objects

info:eu-repo/semantics/publishe

Experimental investigation of the influence of the stress state on the mechanical stability of austenite in multiphase steels

The transformation-induced plasticity (TRIP) effect, i.e. the mechanically activated martensitic transformation of metastable austenite, has been proven for some years to contribute very effective to the deformation process in a large variety of iron-based alloys. In order to enlighten the influence of the stress triaxiality on the kinetics of the mechanically-induced martensitic transformation in TRIP-assisted multiphase steels, several specimens presenting austenite with different mechanical stabilities were strained under different stress states (pure uniaxial tension, uniaxial tension of notched and DENT specimens and stretching). It is shown that the stress triaxiality has a large effect on the mechanical stability of austenite dispersed in a multiphase microstructure and consequently on the mechanical properties of the investigated steels