When do we use "I have been living" rather than "I lived" ? As for me, I naturally say "I lived in Paris" when I want to speak about my own past but "I have been living in Paris" sounds strange for me and I would use "I have lived in Paris"... Could you help me to understand ?

News From France There we go: After few months, I come back to Italki, one of the bests solutions for unwinding and talking about my problems. Lot of things have occurred since the last time I wrote something here. I finished my competitive exam after orals in Paris implying the end of my preparatory class and the beginning of the high engineering schools. Unfortunately not. I eventually was accepted in a chemistry school but it is definitely not what I am interested in.. So remained for me one last solution: repeating a year in order to get a most prestigious (and interesting) school. Lot of Friends were in the same case as me but they did'nt attempt to repeat a year. As a result, I am here, alone in this difficult class, working every day and every night, seeing my friends happy in their respectives schools. I would like to be happy too, one day, just like them. And one day, I'll celebrate getting into the school I have always dreamed of. The only thing I learned from this experience is that even if you aren't the best at school or in other domain, you can distance yourself from others with your motivation. Some people have natural abilities for learning something but one should bear in mind that no matter who you are, you always can make them lag behind by hardworking. Never give up and no dream can resist to you. If you feel like you're in the same case as me, hold on ! We will make our dreams come true.

An Abstract for my School Project (thanks for correcting me) Like other home heating techniques, induction is designed to be all the more energy-efficient as it is efficient on a daily basis. By concentrating on estimated melting time of an induction furnace, it can be noticed that counter-intuitively, the more we try to melt a large piece, the faster the piece melts. This theoretical observation verified by the experiments carried out can be explained by the fact that the eddy currents which result from induction are all the more present as the armature is large, what has to be considered in order to optimize the system.

A difficult life Today, I have to get up early. The first day of my reviews, it would be stupid to overlook the work and to simply lay down as a couch potatoe. I often wonder if I am really in the most important period of my whole life. If my future engineering school isn't the same as in the one I would have liked to enter, will I waste my time and later have a job I don't want to have ? Fortunately, one should bear in mind that here in France, there are thousands and thousands opportunities to do what you want to do, no matter where you're graduated from. It reminds me of a friend who studied in a school of biology. Despite his diplomas which didn't correspond to the jobs in this field, he apllied for a top-job consisting in testing air planes and finally got the job. That is to say excepted in some cases, whoever you are, wherever you are, whatever you do, there is always somewhere a little opportunity for you to do what you want to do and there is no one in this world to judge you for it. This opportunity waits for you and for nobody else.

The incredible science of laser (thanks for correcting me) You're holding a lamp in your hands. The light arriving from the lamp illuminates the place by all the directions of the space, very useful when you're in the dark. Now, imagine you're also in the dark but you want to focus simply on a little stain. A real lamp isn't useful anymore and you need a source which illuminates just the stain. Since the beginning of the humanity , lot of scientist have worried about a solution for this problem. A discover by Einstein in 1917 led to the birth of a ray with a very small radius: a laser. Nothing very suprising until now, but do all of you know how a laser works ? First, as an information, "laser" comes from "Light Amplification by stimulated Emission of Radiation". One should Bear in mind that each atom has two possible states: a neutral state E1 and an excited state E2 (E1-When a photon penetrates a neutral atom (that is to say at a level of energy E1) the latter absorbs it and the atom becomes excited (at E2) -An excited atom can emit naturaly a photon and become neutral (1) -When a photon penetrates an excited atom, the latter emits two photons in exactly the same directions as the first one (2) In a laser there is a huge amount of neutral and excited atoms between two mirrors. Most of them are excited. When the first one emits naturaly a photon (1), it will engender by butterfly effect the emmision of most of the other photons from the other atoms (2) always in the same direction as the first one. Thanks to the mirrors, the accumulation of photons in the same direction creates the unidirectionnal laser. It's very funny when we think that we began with a little excited atom ! The differents colors of laser that we can see in the world simply come from the fact that the difference of energies (E2-E1) is proportionnal to the frecuency of photons emmision and so the wave lenght emitted hence the differents colors.

My future exam On the eve of the most important english exam in my whole life, I feel all at once exited and stressed... Exited because one of my biggest dreams is to be able to speak with perfect fluency the english and stressed because it will be an exam based on writting abilities. That is to say that I have to build my sentences clearly, without any error and all the same with lot of high language level. One of the reasons why the live of an ingeneer is always prone to be difficult. You've understood: that's very hard for me. Since I started learning english, I always have had the same problem: I hardly succeed in making some sentences with a real sense and afterwards, by wanting so much build beautiful sentences, they become very complicated and finally totally incomprehensible. Nevertheless, one should bear in mind that in my studies, it's high time my english turned into a clear language. Heck, another challenge for me: settle the problem within my competitive exam ! But.. As for now, I should go to bed !

The wonderful tables of multiplication. Do all of you know the famous multiplication tables like 1*4=4, 2*4=8, etc.. ? Those tables can seem to be really easy to understand and remember but as a matter of fact they hide a wonderful secret... Imagine a big circle cut in 10 parts (just like a cake). You can numerate the parts by beginning in the right side of the circle and turning as contrary to the clock direction. Now, we're going to represent and draw the table of 4. For that, take the first point in the circle corresponding to the first part of the circle and link it with a line to the point corresponding to the 4*1=fourth part of the circle and link this latter to the 4*4=sixteenth part of the circle. When you exceed the 10 parts of the circle, you have to continue turning around the circle (what we call a "modulo" of 10 in mathematics) Now link this point to the 4*16=sixty-fourth part of the circle and keep doing it to inifinity. As a result, you get a wonderful rosette which represents the real table of 4. You can try to make this figure with an informatic program and if you choose a big number of parts for your circle (like 200 for example), you can make the experience with any integer number to inifnity and represent its multiplication table. Each rosette you get from each experience for each number is simply unique and beautiful. If you want to see an example of that, you can watch the picture below showing the table of 5 with 200 parts for the circle. I programmed it on Python language and it's very captiving to watch it.

What are you working in or studying this year ? As for me, I study math and physic in a preparatory class for high scientific engineering school, a sort of highly selective undergraduate program that we call "classe prépa" in France. It's very interesting and very difficult 'cause we have to study lot of subjects and if you don't like to work, you simply can't be up to standard for the competitive exam. However it's important because I would like to work in space and aerospace later. One of my biggest dreams is to have the opportunity to work for the NASA in the USA or the ESA in Europe. What about you ? 

A difficult year Now we're on January. All the Christmas and new year parties are far away behind me. All the people who talk to me are used to say that it's time for me to work and prepare my competitive exam that will take place in few months. Meanwhile, I would like to say to those people that, as a young but not less responsible boy, I would like to live my own life peacefully and to live my student life just like other students are allowed to live. Whether it be for parties, for the discover of lot of passions, for spending time with your family, or for practicing an instrument, it seems that you don't have time enough when you study math and physic in a preparatory class for high scientific school, what we call "classe prépa" in France. But you have to.You have to work if you want to make your dream come true. Don't let other people tell you that you're a stupid person who knows nothing and keep believing that you'll always have people who count on you no matter what you do and what you decide. As we often say here in France: the future belongs to those who gets up early