Posts in category Q4

Blog 11: Finishing up Year 1 and looking forward


the past weeks have, again, been quite busy and stressful, but I managed at least;)

We have finished the Processor Design Project course, although we haven’t received a grade yet, so it’s to be decided if we are done after all;) The deadline of the report/design was last Monday (June 13th), so that Sunday we spent the whole afternoon and night on finishing up our design and to make our report. Unfortunately, we were not able to implement the 2-way associative cache. It seems that the memory structure that was implemented was optimized for Direct Mapped, so if we are to get the 2-way associative cache to work, we should look at the memory structure as well (instead of just looking at how the entries are stored). Luckily we achieved other improvements: bigger cache and better DDR to cache mapping and a Radix-4 multiplier and divider that need 16 instead of 32 cycles to get the result. The overall result is an increase in performance of almost 62.5% with negligible power increase (0.001 W); the area increase is significant unfortunately. Increasing block size (instead of retrieving 32 bits from the DDR at once we retrieve 64 bits) seemed to work except on one benchmark. The results of our improved processor in comparison with the baseline are shown below. 2 days after the deadline we had a symposium in which we showed our design and the results. The conclusion we took home was that we should have done a proper benchmark analysis. If we had done that, we probably wouldn’t have tried (and failed;)) to implement a branch predictor.

Improved processor vs baseline on needed execution cycles, area and power usage (Click for a better view; note: Y-axis is performance, meaning 1.x is better and 0.x is worse)

Improved processor vs baseline on needed execution cycles, area and power usage (Click for a better view; note: Y-axis is performance, meaning 1.x is better and 0.x is worse)

After PDP (temporarily) finished, I’ve been focusing on Quantum. Before this, however, I finished labs 3, 4 and 5. Labs 4 and 5 went pretty well, so I expect good grades;) As I was saying, last week till today I have been focusing on the Final Lab of this course (there is no exam). It consisted of 5 assignments (related to quantum circuits), of which assignment 3 was the hardest. Last week I finished all assignments except 3; it took me quite some time however. The assignments were definitely harder than the previous 2 labs, however this only meant I had to spend more time on them. I’m pretty sure I did quite well on these 4. One assignment was working on the Ninja Star circuit which can be seen below.

Example of a Surface Code circuit. If there is no error (0 instead of 1 for example) in any of the data qubits (D1-D9), no ancilla qubit (X/Z1-X/Z4). But let's say there is a bit-flip error in D3. This means that ancilla Z3 fires and becomes 1 (Z ancilla's fire when there is a X/bit-flip error).

Example of a Surface Code circuit. If there is no error (0 instead of 1 for example) in any of the data qubits (D1-D9), no ancilla qubit (X/Z1-X/Z4) will fire. But let’s say there is a bit-flip error in D3. This means that ancilla Z2 fires and becomes 1 (Z ancilla’s fire when there is a X/bit-flip error).

The 3rd assignment was about Grover’s algorithm, which is quite ingenious. It would take me some time to explain it, so instead I give you a link for the interested people;) I will say this, however: this algorithm is a good example of why Quantum Computing shows promise.

System Engineering:( Last Friday the symposium was held. I have to admit that it was pretty interesting to see what the other groups have worked on (2 minute pitch per group only;)) and to look at other groups’ posters. We also had to defend our own poster, which wasn’t that bad. Anyway, the course is finished now:) All that is left is to wait for the grade, hopefully I will get it soon!

So what’s next? Coming Tuesday is my (voluntary!) retake for Computer Arithmetic; let’s see if I can improve my grade. I only got a 6 on the exam, while I got a 8.something on the take home exam. I will also have to start on the VLSI SoC project with my partner. Probably we will do that next week after the retake. Somewhere these 2 weeks I will also meet with my internship supervisor, so that he can sign my application form. Then I can hand in this application form and just wait for approval:)

Oh, I forgot one thing. The past weeks I’ve also been talking with Dr. R. van Leuken of the Circuits and Systems group (CAS) here at the TU. He signed my Individual Exam Programme (basically your list of courses), so I will most likely (99%) do my Master Thesis with him as supervisor, next year when I get back from my internship in Germany. I advice you all to arrange these things a little bit earlier;) It takes more time than you image to arrange an internship and your Master Thesis:(

One more thing: Holiday:) I got my visa without further problems, so next Friday (July 1st) I will embark on the plane to China:D I’m thrilled to go; I’m less thrilled to pack:P Most likely I will also work on VLSI SoC in China and work on my Chinese, but the main focus will be holiday;)

I’m not sure when my next blog will be, it might be somewhere in the holidays, otherwise it will be when I get back (either from China or internship). I hope you at least enjoyed my blogs a bit, but most of all that they were helpful. Hell, maybe I convinced some of you to join me next year in CE 🙂

That’s it for me for now. Good luck finishing this school year, and have an amazing holiday. Hope to see some of you in Delft next year:P

Blog 10: Mid-way Q4

Hi y’all,

it has been over a month since my last blog, which is a bit too much. I almost forgot to post today as well:(

The past month has been quite busy at times, but at times it has been pretty relaxed as well. Quite some things have happened since the last time, so let me start.

I’ve had the milestone meeting for Processor Design Project. After a few days of hard working we finalized the changes to the cache. By just changing the cache size and mapping, we already achieved a small performance increase. But of course that’s not enough. The last 2 weeks I’ve been working, again, on the cache; I’m trying to change the mapping from direct mapped to 2-way associative cache. I’ve been unlucky so far, meaning I have some work to do coming two weeks. The deadline is nearing as well:(

Direct Mapped vs 2-Way Associative

Left: Direct Mapped, each main memory entry can only be stored in one cache entry.
Right: 2-Way Associative, each main memory entry can be stored in two cache entries.
So, in Direct Mapped if the cache entry is already occupied, the entry is discarded and replaced by the new entry. In 2-Way Associative, an entry is only replaced if both of the entries are occupied; so if only 2 main memory entries are competing for the same spot they are both stored.

The Quantum course has been really busy. Besides the usual following lectures, we have had labs. The first 2 labs were not really related to quantum; we had to model amplifiers (lab 1) and an amplifier plus Analog to Digital Converter (lab 2) in Matlab. These labs were more difficult than expected, and I’ve put a lot of work in them. The third lab is a bit more related; first a ‘normal’ silicon transistor has to be modeled and analyzed and after that the same has to be done for a silicon-germanium transistor (which is believed to be a possible solution in Quantum mechanics). This all had to be done in a simulator called COMSOL. The deadline for this is coming Monday. The fourth lab is very much related to Quantum; using a quantum simulator written by a PhD student we have to model not only quantum gates, but also slightly bigger circuits (for example a 2 bit counter). The deadline for this lab is coming Friday, and I’m well on my way to finish it. The course so far has been quite interesting, but also rather difficult. I don’t regret taking this course (yet) though, eventhough most of my time goes to this course.


Modeling a Silicon MOSFET transistor in the COMSOL simulator (Click the picture for a bigger one).

I don’t want to talk too much about System Engineering, but the report is hopefully almost finished. We had weekly meetings in which we divided the work, and then we just did the work. Every Friday one of us gave a presentation to the other groups and the supervisor (this week it’s my turn:P), and then we would get feedback on our report. Together with Q3 we/I put a lot more hours in this course than the 3 ECTS warranties unfortunately.

About the VLSI course nothing much is there to be said. So far I’ve just been attending the lectures. Coming Friday he will go into details about the 3 projects, and I’ll have to choose one together with my partner. It is still my plan to work on it before the holiday starts, but I’m not sure if I’m able to follow that plan:P

I’ve not only been busy with the courses. I’ve actually been quite busy getting an internship. And you know what? I succeeded:)!! At the end of August I’m going to Munich for an internship at Huawei for 10 weeks. I’m really excited, and nervous, about it. I already know the project I’m going to work on but not the details. I’m going to work on Lightfield Display design for Virtual Reality.

For those of who you don’t know what Light Field is, let me explain it in short. Light Field is all lightrays in each point in space moving in each direction; in other words it’s 4D, x and y direction and theta and phi angles. Currently this phenomenon is used in so called LightField Cameras. You know that when you’re taking a picture you have to focus your camera (so either what’s close to you is sharp or what’s far away)? With LightField Cameras this is not the case. You just take the picture, and afterwards, with software, you can change the focus over and over. This is possible because all the information is stored in the Light Field.

Example Light Field Camera

Example of a Light Field Camera. As can be seen, each of the balls, no matter their distance, has the same focus.

But that’s for cameras. My project is related to VR. This is because recently it has been discovered that Light Field can improve VR. Currently, using VR might make you nauseous. This has to do with your eyes not being able to change focus since every image is displayed (on a display) on the same short distance to your eyes. You can already guess, Light Field might be able to solve this problem, by constantly changing the focus, mimicking the reality better. I didn’t know anything about Light Fields before I got this internship, but now I’m really interested. I almost can’t wait to start:) (of course, I want to enjoy my holiday first!)

Talking about the holidays, I’ve already booked my tickets:) From July 1st/2nd till August 22nd I’ll be in lovely China. At least, that’s the plan, but I don’t have a visa yet. 2 weeks ago I went to apply for it, but they didn’t accept it, and they told me I can’t spend so much time in China without leaving in between. So 1 week ago I went again, this time with my Chinese girlfriend. After 10 minutes of Chinese talk they solved the problem and suddenly I might be able to stay this long. Lesson learned: bring a Chinese person if you want to apply for a Chinese visa. Although it also helped that the second time the lady could speak Dutch:P Coming Thursday I’m going there again to pick up my visa; let’s hope they don’t call me before then saying there is a problem;)

Well, that’s it for now. Maybe it seems like I haven’t been all too busy the past month, but let me assure you: I have been quite busy the past month;) Luckily, having only lectures on 2 days helps a lot with that:P I really hope I won’t forget to write my next blog; I’ll try to be faster than this time as well:P

Till next time, cheers:)!

Oh, and it looks like summer is coming back slowly. Don’t forget to enjoy it while it lasts;)!

Blog 9: Starting Q4 and LoL


it took me a bit longer than expected to write this blog, but c’est la vie I guess. At least things have happened since my last blog:)

I have worked hard on my practice exam for Computer Arithmetic. I think I’ve spent at least 10 hours on it. This was mostly because I had to get familiar with the material and look at some examples. Honestly, I have spent the whole week before the exam, minus 2 days, on this practice exam, so I was a bit nervous for the exam; the exam is only 3 hours. The last two days I focused on other material in case that would be in the final exam. The exam itself was okay-ish. Unfortunately I didn’t manage my time well and as a result I couldn’t finish 1.5 out of 9 questions. Nonetheless, I thought it went pretty okay; today I got the confirmation: I have a 7:) I’m not quite sure if that’s only my final exam, or my take-home exame, or both, but whatever! I’m actually a bit disappointed; I hoped for an 8.

I have also uploaded my final essay for Network Security. I’m glad it’s finished, I’ve put a lot of effort in it. I also finished the third and last exercise sheet, which was posted the day of the NXP trip. It consisted of only two questions and an optional programming part. I’ve chosen to not do the programming part due to my oral exam of VLSI TTR on Monday (i.e., today; deadline of the sheet was Sunday, i.e., yesterday). The questions were not hard, so that should be fine. I’m still waiting for my essay- and final grade. I think I will pass this course, but I want to know for sure;)

Friday the 15th of April we went to NXP in Nijmegen for the VLSI TTR course. It was quite interesting; a few lectures were given and I’ve seen quite a lot of different test machines (seeing the machines was quite impressive). There are possibilities for an internship or master thesis at NXP, which is pretty cool:) Besides the visit, I also need to finish the course; that’s exactly what I’ve done today. I took the oral exam together with my two colleagues with which I’ve done the assignments. The exam took about 2 hours:( Honestly, it could’ve went a lot better, but it turns out I did well enough to get an 8:D Thus I’ve passed this course:)

The exam for Systems Engineering didn’t go as planned unfortunately. I’m still being hopeful, but I’ll have to wait. It was only 3 questions (with each 3 sub-questions), but it consisted of a lot of reading work (which I had anticipated). I can honestly say that my writing hand was super tired after the exam:P

This quarter I decided to follow three courses besides Systems Engineering: Processor Design Project (track course, so not really a choice;)), VLSI System on Chip and Electronics for Quantum Computation (both specialization courses). VLSI SoC is basically for extra credits, since I’m planning to do an internship of 15 points (initially I planned to follow courses for 11 ECTS next year); without this 4 ECTC, I already have enough non-thesis credits.

Processor Design Project is quite interesting. There was one kick-off lecture, and there will be an intermediate meeting to see if we are on the right track, but for the rest there is nothing planned. We are given a processor design written in VHDL, and we have to make it faster in groups of three. This course follows Computer Arithmetic, so surely there are arithmetic optimizations to be done, but you can also think of architectural optimizations. I already have a group, and for coming Wednesday I will look at the source code and the course description, so that we can discuss it on Thursday.

VLSI SoC seems like a really interesting course, hence why I’m taking it for extra credits. For now, lectures are given (though not in the coming two weeks), but after that you have to design a System on Chip in groups of 2 (or 1). The deadline is very lenient; if you want you can send it in the summer, or even next year. I’m going to work together with Reynaldi again (same partner as Digital IC Design), and obviously we are trying to finish it before the summer. I will elaborate more on the project in one of my next blogs!

The quantum course is looking to be quite intensive and complex. I think it will be interesting though. The main reason I’ve chosen this course is because of the Quantum part, which is a trending and upcoming part of Computer Engineering. Did you know Intel invested 50 Million Dollar in TU Delft to design a working Quantum Computer? So yeah, Quantum Computing is quite big at the moment, so I thought it would be interesting to follow is course (unfortunately I didn’t follow introduction to Quantum Computing in Q1). For this course, there will be lecutres and lab assignments. The first lab assignment is due coming Friday and it looks quite complicated:O.

My schedule of this quarter is pretty empty. Tuesday I have 2 lectures and Friday I have 3; the rest of the days I have nothing scheduled. But surely project meetings will be scheduled on these days:( This quarter is looking quite interesting, so I am looking forward to it. However, it’s also looking intensive and I almost can’t wait for the summer holiday:(

As mentioned in my last blog, LCS (League of Legends Championship Series) Europe Finals came to Ahoy in Rotterdam. Together with a lot of people of the E-sports club in Delft (DSEA) I went to this event as a volunteer. It was really amazing and I’ve had a blast. Saturday I applied (not-so) temporary tattoos on peoples arms, and sometimes faces, and on Sunday I took pictures of the crowd with famous youtuber Sp4zie (you can probably see me in his latest vid). After the tattoos I watched the 3rd place match (see picture) which was awesome eventhough the team I was rooting for lost, and after taking pictures I watched the finals which was even more amazing, also beacause the team I was rooting for won. This was my first E-sports/LoL event, and I certainly hope it’s not my last. After the games, I took pictues of the crowd with the players and shoutcasters. A bonus: afterwards I also took pictures with the teams and casters (4 times haha). I also met and talked with a retired German player (CandyPanda) who was behind me in the line for ice cream, and I talked with the owner of the winning team. All in all, it was amazing and to all of you LoL fans: next time it comes to Rotterdam, you should go there; I know I will:)

Inside Ahoy. On screen the casters, on stage the players. That's a lot of people:)!

Inside Ahoy. On screen the casters, on stage the players. That’s a lot of people:)!

On the photo with Fnatic:)!

On the photo with Fnatic:)!

I have busy weeks coming up. I hope I will have the time to write another blog (again, shorter interval than between this blog and the last).


Small edit: I’ve mentioned that I want to do an intership first quarter of next year. In my next blog, when I hopefully have more information, I will elaborate on this!

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