Learning Records Category

Docker vs Podman

Purpose: Podman is a Docker-compatible, daemonless container engine focused on security and compatibility with OCI.
Security model: Rootless by default via user namespaces; works with SELinux/AppArmor; reduces blast radius compared to a rootful daemon.
Architecture: No central daemon; containers are regular processes managed by the user; integrates well with systemd (generate unit files, manage lifecycle).
Docker compatibility: Largely CLI-compatible; can run Docker images; podman build (powered by Buildah) supports Dockerfiles; optional Docker REST API socket for tooling compatibility.
Kubernetes integration: First-class pod concept; podman generate kube exports manifests; podman play kube runs manifests locally; smoother dev→K8s workflows.
Networking: Uses CNI plugins; rootless networking relies on slirp4netns (some port/MTU limitations); differs from Docker’s default bridge but offers comparable outcomes in most cases.
Storage: OCI image layout; OverlayFS where available, fuse-overlayfs for rootless; supports volumes and image management similar to Docker.
Compose: Supports podman-compose; with the Docker-compatible socket, many docker compose workflows can work, though features may vary by version.
Cross-platform: Native on Linux; macOS/Windows use Podman Machine (a lightweight VM), similar conceptually to Docker Desktop.
Performance: Lower overhead on Linux without a long-running daemon; on macOS/Windows performance depends on the backing VM.
Use cases: Security-conscious environments, rootless CI, local K8s-oriented development, and servers where a daemon is undesirable.
Limitations: No persistent daemon to auto-manage state; some rootless networking constraints; ecosystem around Compose and third-party tools can be uneven versus Docker.

Ruochen ChenOctober 3, 2025Less than 1 minute

Information Visualisation (GEOM90007)

Week 1

Principles of Data Graphics

Data Density

Data density = Number of entries of data matrix / Available display area

Data Integrity

Data scrubbing

Deliberately removing data or deriving data (smoothing/resampling) to create a false message

Ruochen ChenAugust 1, 2025Less than 1 minute

Internship note

CI Tools

1. JaCoCo (Java Code Coverage)

Purpose: Code coverage analysis tool

Measures how much of your source code is exercised by your unit tests
Tracks:
- Line coverage
- Branch coverage
- Method/class coverage
Generates visual HTML reports showing what parts of code are untested

Ruochen ChenJune 25, 2025Less than 1 minute

Machine Learning

Algorithm	Type	Generative/Discriminative	Linear/Non-linear	Notes
Naive Bayes	Classification	Generative	Linear	Assumes feature independence, uses Bayes' theorem
Logistic Regression	Classification	Discriminative	Linear	Uses sigmoid function, mainly for binary classification
Decision Trees	Classification	Discriminative	Non-linear	Handles both numerical and categorical features
SVM	Classification	Discriminative	Linear/Non-linear	Uses kernel trick for non-linear, finds optimal hyperplane
k-NN	Classification	Discriminative	Non-linear	Instance-based, sensitive to feature scaling
Neural Networks	Classification	Discriminative	Non-linear	Can model complex patterns, requires large datasets
Linear Regression	Regression	Discriminative	Linear	Predicts continuous values, sensitive to multicollinearity
k-Means	Clustering	-	Linear	Unsupervised, sensitive to initial centroids and outliers
PCA	Dimensionality Reduction	-	Linear	Unsupervised, maximizes variance, does not consider class labels
Hierarchical Clustering	Clustering	-	Non-linear	Unsupervised, builds nested clusters, linkage methods affect results
Perceptron	Classification	Discriminative	Linear	Simple model, only for linearly separable data
Multi-Layer Perceptron	Classification/Regression	Discriminative	Non-linear	Can solve XOR problem, uses backpropagation for training

Ruochen ChenJune 19, 2025About 31 min

Create MCP Server

# server.py
from mcp.server.fastmcp import FastMCP

# Create an MCP server
mcp = FastMCP("Demo")


# Add an addition tool
@mcp.tool()
def add(a: int, b: int) -> int:
    """Add two numbers"""
    return a + b


# Add a dynamic greeting resource
@mcp.resource("greeting://{name}")
def get_greeting(name: str) -> str:
    """Get a personalized greeting"""
    return f"Hello, {name}!"

if __name__ == "__main__":
    mcp.run(transport="stdio")

Ruochen ChenJune 5, 2025Less than 1 minute

Sealos

Sealos is a container management platform that provides a unified interface for managing containerized applications, including application deployment, monitoring, logging, and alerting.
Sealos can connect projects to local IDEs for development and debugging.
Sealos can create virtual machines and deploy applications to them.
Sealos can manage the lifecycle of applications, including deployment, scaling, and deletion.
Sealos can provide a unified interface for managing containerized applications, including application deployment, monitoring, logging, and alerting.

Ruochen ChenMay 28, 2025Less than 1 minute

Collection of all tools

DigitalPlat

A digital platform typically used for enterprise digital transformation, integrating various business management and data analysis tools to improve operational efficiency.

NameSilo

A well-known domain registrar that provides domain registration, management, and transfer services, famous for transparent pricing and free privacy protection.

Ruochen ChenMay 8, 2025Less than 1 minute

Cloudflare

Practice

Sucessfully deployed Resume on Resume-EN and Resume-CN. The domain name is free from digitalplat, and used Workers and Pages in CloudFlare to deploy.

Ruochen ChenMay 7, 2025Less than 1 minute

LeetCode Summary

Array

HashMap

Stack and Queue

Binary Tree

Depth-First Traversal Preorder Traversal (Recursive, Iterative) Left-Right Inorder Traversal (Recursive, Iterative) Left-Middle-Right Postorder Traversal (Recursive, Iterative) Left-Right-Middle Breadth-First Traversal Level Order Traversal (Iterative)

Ruochen ChenMay 3, 2025Less than 1 minute

TailWind CSS Contents

1. Summary

Ruochen ChenApril 22, 2025Less than 1 minute