Chan Si Yu, David

Experience

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  Tinkertanker

  Jan 2021 - Dec 2021

  Swift Accelerator Programme Student

  The Swift Accelerator Programme is an intensive talent development programme for secondary school students with an interest and aptitude for app development and computational thinking. Over 8 months, participants learn to code in Swift, and apply story-telling and design thinking principles to design, build, and release an iOS app of their own.During this programme, I also worked in a team to design and publish an app on the apple store. The app is named 'Showery', with the purpose of helping users keep track of their water consumption during their showers, and provide tips on how to minimise water wastage. Show less

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  Singapore Management University

  Feb 2022 - Dec 2022

  Student Researcher

  My group took part in the Science Mentorship Programme and concurrently the SMU Mentorship Programme, and was attached under Professor Aldy Gunawan. We did Operations Research into the algorithms to optimise vehicle routing for Singapore E-waste collection. We built on algorithms like the Greedy Algorithm, adding our own algorithms to swap nodes, construct turning capacities to determine the vehicles' directions, functions to prioritise different variables and parameters, etc. After coming up with the optimisation algorithms, we represented our data on a website that displays a Mapbox API to show the routes that the vehicles would take to deliver the e-waste from across the country. Show less

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  Ministry of Home Affairs Singapore

  Dec 2022 - Feb 2023

  Intern

  During the internship with MHA, I undertook 2 projects. For the first project, I did a study into the digitilised services and key touchpoints of HR Services Centre, and researched on the possible ways to improve the service experience. I researched into what other organisations did to enhance customer service by introducing self-service options, and propose possible implementations into MHA's context. For my second project, I programmed a python tool to automate the creation of the Certificate of Service. The certificate is given to officers leaving MHA, and it contains all the past appointments and achievements of the officer. To reduce the manpower needed to create this certificates manually. The tool is able to take in details of information of the officers, and create the entire batch of certificates onto individual Word documents for the respective officers. This not only saves a lot of time for manual work, but also increases the accuracy of the certificates themselves. Show less

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  DSO National Laboratories

  Mar 2023 - Dec 2023

  This is a year-long research programme, known as Research@YDSP. We are privileged to have a talented cybersecurity researcher from the DSO National Laboratories, Phyllis, as our mentor. We began our research journey in April in hybrid mode, followed by a full time internship from November to December. Under our research project titled "Can LLMs Have a Fever? Investigating the Effects of Temperature on Large Language Model Security", we introduced a new field of research we termed as "grey-box testing", specifically in LLM security.To the best of our knowledge, we conducted the first ever study on the effects of temperature on LLM security, on 4 top-performing LLMs: Vicuna, Llama 2 Chat, Mistral and ChatGPT. We found a clear correlation between temperature and jailbreaking, which is the manipulation of LLMs to produce harmful content. Our team was also nominated to present this project at YDSP Congress 2024, held in Marina Bay Sands Convention Center, with Senior Minister of State Mr Heng Chee Howe as the Guest-of-Honour. Show less

  • Intern

    Nov 2023 - Dec 2023

  • Student Researcher

    Mar 2023 - Nov 2023
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  Social Engineering Experts

  Jun 2023 - Jan 2024

  CTF Player

  As I was new to CTFs, I learnt a lot from experienced players in the team to improve myself in the area of Cryptography.

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  Singapore Students Merger CTF Team

  Mar 2024 - now

  Founder

  I started this merger team with many different CTF teams across Singapore with a goal to support and provide opportunities for students that are interested in cybersecurity, to network and share their knowledge with one another. We play international CTFs on CTFtime almost every weekend, and some of us organise various CTFs locally too.https://ctftime.org/team/299075Achievements:1st - OSCTF 20242nd, 3rd, 9th - BTCTF6th (HS) - BCACTF10th - SpringForwardCTFWe are currently recruting players from Singapore from Secondary to Uni-Postgrad level, if you are interested, you can apply on discord and we can get in touch! https://discord.gg/GSwXHeRJMerger Team consists of CTF players from:404Unfound (NP)Archiv3 (NTU)AIVINA (NS)c00k1e_cptr (ASRJC)F1GhtTh3BugV7 (Mix)jess fan club (SP)RainbowHash (HCI)RVCTF (RV)rwandi (NUSH)TOP PROGRAMMER 2005 DATABASE MAESTRO (NS)YBN (Mix) Show less

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  ISC2 Singapore Chapter

  Aug 2024 - Aug 2024

  ISC2CTF Challenge Author

  I crafted challenges under the Cryptography and Reverse Engineering categories for members of ISC2 for the 8-hour ISC2CTF on 31st August 2024, and served as technical support.

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  Yes But No

  Sept 2024 - Nov 2024

  YBN CTF Challenge Author

  I came up with CTF challenges under the Cryptography, Miscellaneous, Reverse Engineering, OSINT and a bit of Web exploitation categories with a range of challenges of different difficulty, while providing the participants technical support where needed.As the Singapore Students Merger, we supported YBN CTF 2024 in co-authoring challenges and providing technical support.

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  Singapore Army

  Jan 2025 - Mar 2025

  Recruit
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  The Digital and Intelligence Service (DIS)

  Mar 2025 - now

  C4X MIlitary Expert Trainee