https://log.zxcvber.com/Life LogRecording Life. 2024-04-13T00:10:01+09:00 Sungchan Yi https://log.zxcvber.com/ Jekyll © 2024 Sungchan Yi /assets/img/favicons/favicon.ico /assets/img/favicons/favicon-96x96.png Search Time in Hash Tables2024-04-12T00:00:00+09:00 2024-04-12T00:00:00+09:00 https://log.zxcvber.com/algorithms/data-structures/2024-04-12-search-time-hash-tables/ Sungchan Yi Here are the expected time complexities of the search operation in hash tables. Assumptions Let $m$ be the number of buckets in the hash table. Let $n$ be the number of entries currently in the hash table. Let $\alpha = n/m$ be the load factor. Elements are uniformly hashed to each bucket of the hash table. These results imply that the search operation takes almost constant time. ... You and Your Research, Richard Hamming2024-03-11T00:00:00+09:00 2024-03-11T00:00:00+09:00 https://log.zxcvber.com/articles/2024-03-11-you-and-your-research/ Sungchan Yi Link to original text. I recommend reading the full text. It may seem a bit long but I assure you that it is worth the time. The talk is mainly about how to do first-class work, something significant as a great scientist. The following is a list of quotes from the text that inspired me. Bold fonts were not in the original text, I added them on my own. Read the full text for the full c... Secure IAM on AWS with Multi-Account Strategy2024-02-26T00:00:00+09:00 2024-02-27T00:31:57+09:00 https://log.zxcvber.com/development/2024-02-26-secure-iam/ Sungchan Yi 2024. 2. B.S. Graduation Paper, Received Best Paper Award! Secure IAM on AWS with Multi-Account Strategy (pdf) Presentation Poster (pdf) Abstract Many recent IT companies use cloud services for deploying their products, mainly because of their convenience. As such, cloud assets have become a new attack surface, and the concept of cloud security has emerged. However, cloud security is... 18. Bootstrapping & CKKS2023-12-08T00:00:00+09:00 2023-12-08T00:00:00+09:00 https://log.zxcvber.com/lecture-notes/modern-cryptography/2023-12-08-bootstrapping-ckks/ Sungchan Yi Bootstrapping Recall that BGV has a limit on the number of operations, so it cannot evaluate a circuit with a large depth. This was because of the growing noise, so we need a way to remove the noise. An easy answer is decrypting the ciphertext and encrypting it again, but we want to do it without using the secret key. Bootstrapping is a method to convert SHE into FHE. Key Idea The main ide... 17. BGV Scheme2023-11-23T00:00:00+09:00 2023-11-23T00:00:00+09:00 https://log.zxcvber.com/lecture-notes/modern-cryptography/2023-11-23-bgv-scheme/ Sungchan Yi Homomorphisms Definition. Let $(X, \ast), (Y, \ast’)$ be sets equipped with binary operations $\ast$, $\ast’$. A map $\varphi : X \ra Y$ is said to be a homomorphism if \[\varphi(a \ast b) = \varphi(a) \ast' \varphi(b)\] for all $a, b \in X$. A homomorphism sort of preserves the structure between two sets.1 We will mainly consider additive homomorphisms where \[\varphi(a + b) = \var...