Patrick Lee

Experience

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  CEA - Commissariat à l'énergie atomique et aux énergies alternatives

  Apr 2011 - Jun 2011

  Intern

  Nanoparticles have shown some interesting properties in increasing the efficiency of certain products, for instance in cosmetics, photovoltaic applications etc. However studies on the toxicity of nanoparticles are still ongoing. The main objective of this internship is to prepare TiO2 nanoparticle samples for the toxicity studies carried out by the biologists. Most of the work is in the characterization of the in-house synthesized TiO2 nanoparticles by laser pyrolysis. A study on the effect of annealing on the dispersion (how the nanoparticles are distributed in a medium) is also carried out. Depending on the temperature, the time of annealing and the quenching method, different properties of the nanoparticles can be obtained. An extensive study has allowed us figure out parameters that give samples that meet the criteria for the biologists' toxicity studies. Show less

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  Jimah Venture Sdn. Bhd.

  Jul 2012 - Aug 2012

  Electrical Engineering Intern

  In Malaysia, most of the electrical power supply either comes from the coal power plant or hydropower plant, Jimah Venture Sdn. Bhd is one of the coal power plants situated in the district of Port Dickson. The main activity that I was responsible for is to overlook the electrical maintenance of the machines, more specifically the control units in the operation room.

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  CEA - Commissariat à l'énergie atomique et aux énergies alternatives

  Jul 2013 - Aug 2013

  Masters Student

  Nanoparticles of Silicon is a trending material that have the potential to increase the efficiency of photon absorption by a solar cell (PIN junction), this works by quantum dot effect. Quantum dots provide a tunable absorption spectrum and high extinction coefficients. During the internship, I was in charge of the characterization and the performance testing of solar cells containing Silicon nanoparticles.

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  Lawrence Berkeley National Laboratory

  Mar 2014 - Sept 2014

  Masters Student

  The state of the art of simulations in laser plasma based accelerator is conducted using the particle-in-cell (PIC) code, where the governing equations are the Lorentz force equation and the Maxwell's equations. Depending on the physics of interest, we use either the electrostatic (ES) solver or the electromagnetic (EM) solver. When dealing with the propagation of a laser pulse in a plasma, as in the case of the laser plasma based accelerator, the EM solver is used. In general, the boundaries have to be defined with tremendous care to avoid any numerical artifact from jeopardizing the simulation. The perfectly matched layer (PML) by JP Bérenger is such a method for the treatment of the boundaries to allow the EM waves to exit the simulation box, in order not to generate any reflection that might cause interferences with the EM wave that is still in the simulation box.My master thesis consists of evaluating the efficiency of the PML and analytically model the coefficient of reflection in the case of reflection. Show less

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  Université Paris-Sud

  Oct 2014 - Nov 2017

  PhD Student in Modeling of Laser-Plasma Accelerator

  Unlike accelerating particles in vacuum, plasma has the ability to sustain extremely large accelerating gradients (100GV/m for a plasma density of 10^18cm-3), leading to a compact tabletop particle accelerator. My research area includes simulations in Laser Wakefield Electron Acceleration. A lot of work has been conducted in understanding the physics of the creation of electron bunch in the plasma and its dynamics with respect to the laser plasma parameters. Another challenging question that I address in my thesis is the required parameters to create electron bunch with very constraining properties i.e high charge, low emittance and low energy dispersion suitable for a particle collider.My thesis discusses the physics, the laser-plasma parameters and the method for the creation of a desired electron bunch via simulations with a particle-in-cell (PIC) code, together with the discussion on the numerical challenges and solutions. Show less

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  Berkeley Lab

  Oct 2015 - Mar 2016

  Visiting scholar in Modeling of Laser-Plasma Accelerator

  The noninvariance of space- and time-scale ranges under a Lorentz transformation has allowed speedups in simulations of laser plasma based acceleration. Due to the contraction of the plasma and the elongation of the laser pulse under the implication of Lorentz transformation, gains in space (because the plasma is now shorter) and in time (because the crossing time between the two objects has also become shorter) are observed. This Lorentz boosted technique is very promising and is the way to go in the quest of fast simulation, however there are still some open questions, because the Lorentz transformation reduces the numerical resolution in the plasma, does this have a serious consequence on the precision of the simulation?My work is to determine the optimum resolution required to ensure correctness in the simulation results and the consequent speedup that we can obtain. Results show that even with high resolution, we still gain significant speedup. Show less

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  Capgemini Consulting

  Mar 2018 - Sept 2018

  Data Scientist

  Professional training contract with OpenClassrooms

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  Individual clients

  Jan 2019 - Jun 2019

  Freelance Data Scientist

  - Assist clients in solving big data problem, and provide consultation in technology used in Machine Learning Web Application- Develop machine learning web applications in a wide range of fields eg medical, internet phishings and more to come- Take care of the application through and through from development to deployment - Main tools : scikit-learn, keras, nltk, gensim, flask (RestFul web design), aws, networkx

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  OpenClassrooms

  Jan 2019 - Apr 2022

  Mentor Data Scientist

  Mentoring in Data Scientist course in partnership with Ecole CentraleSupélec

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  Capgemini Invent

  Jun 2019 - Sept 2021

  Data Scientist