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254 articles

What Is Idempotency? Designing an Idempotency-Key to Prevent Double Charges on API Retries, Explained With a Real Experiment

July 20, 2026 18 min read

Design API Distributed Systems Microservices
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What Is HyperLogLog? Counting Unique Items in 12KB, with the 1.04/√m Error Bound Verified by Implementation and Experiment

July 20, 2026 16 min read

Algorithms Data Structures Databases Python
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What Is the Circuit Breaker Pattern? A Deep Dive into Closed/Open/Half-Open via Simulation

July 20, 2026 17 min read

Design Distributed Systems Microservices SRE Python
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What Is RRF (Reciprocal Rank Fusion)? A Deep Dive into Hybrid Search Score Fusion with Math and Experiments

July 20, 2026 16 min read

Search Engines Vector Search Algorithms Machine Learning Python
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What Are Percentiles (p50/p95/p99)? Why Average Latency Lies, Proven with Experiments

July 20, 2026 15 min read

SRE Statistics Monitoring Python
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What Is Consistent Hashing? A Deep Dive into the Ring, Virtual Nodes, and Minimal Remapping, Backed by Implementation and Experiments

July 20, 2026 14 min read

Algorithms Distributed Systems Databases Python
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What Is a Bloom Filter? A Deep Dive into the Mechanism, the False-Positive Math, and Optimal Design, Backed by Implementation and Experiments

July 20, 2026 14 min read

Algorithms Data Structures Databases Python
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A Deep Comparison of 4 Rate Limiting Algorithms: Token Bucket, Leaky Bucket, and Fixed/Sliding Windows [Implementation and Experiments]

July 20, 2026 19 min read

Design Distributed Systems Algorithms API Python
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Exponential Backoff and Jitter Explained: The Retry Design Playbook, Verified by Simulation

July 20, 2026 16 min read

Design Distributed Systems Algorithms SRE Python
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Bayes' Theorem Explained: Prior, Posterior, and Bayesian Updating with Worked Examples and Formulas

July 20, 2026 6 min read

Statistics Bayesian Statistics Machine Learning Mathematics
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How to Use Git Hooks: Preventing Direct Pushes to main with pre-push, and Sharing Them Across a Team (lefthook/husky)

July 20, 2026 5 min read

Git Development
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What Is TypeScript's never Type? Implementation Patterns for Exhaustive Checking in switch Statements

July 20, 2026 10 min read

TypeScript
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What Is RAG? A Thorough Guide to How Retrieval-Augmented Generation Works and How to Build It, from Vector Search Fundamentals [2026 Edition]

July 20, 2026 20 min read

RAG LLM Vector Search Machine Learning Generative AI
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SQL Basic Syntax Cheat Sheet: SELECT, JOIN, GROUP BY, Subqueries, and Window Functions

July 20, 2026 17 min read

SQL Database DB Cheat Sheet
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Getting Started with boto3 [Python × AWS]: From Authentication to S3, Pagination, and Error Handling

July 20, 2026 13 min read

AWS Python boto3 Cloud
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[2026] 10 Recommended Technical Books for Engineers: Field-by-Field Classics from a Working Engineer's Perspective

July 20, 2026 6 min read

Book Review Technical Books Engineer Programming
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The Art of Readable Code, Summarized: Principles for Readable Code You Can Apply Tomorrow, with Examples

July 20, 2026 6 min read

Book Review Programming Software Design Readable Code
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GitHubにSSH接続する設定方法【ed25519対応】鍵の作成から接続確認・トラブル解決まで

July 20, 2026 5 min read

Git GitHub SSH 開発環境
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The Complete Guide to Linux Permissions: From What chmod's Numbers Mean to SUID and ACLs

July 20, 2026 17 min read

Linux Commands Infrastructure Security
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The Definitive Guide to Python Environment Setup in 2026: uv vs pyenv vs venv vs conda

July 20, 2026 12 min read

Python Environment Setup uv Developer Tools
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What Is 'use client'? A Deep Dive into the Server/Client Component Boundary in Next.js App Router

July 20, 2026 15 min read

Next.js React TypeScript Frontend
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What Is a DDD Aggregate? A Complete Guide to Aggregate Roots, Invariants, and Transaction Boundaries

July 20, 2026 7 min read

DDD Domain-Driven Design Software Design TypeScript Programming
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Modeling Database Connection Pool Sizing with Queueing Theory (M/M/c)

July 16, 2026 11 min read

Database DB Queueing Theory Statistics Python Simulation
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Understanding SSH Key Exchange Through Diffie-Hellman and Elliptic Curve Cryptography: Verifying curve25519-sha256 and Session Key Derivation in Python

July 16, 2026 12 min read

SSH Cryptography Networking Python
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Anomaly Detection on Prometheus Metrics: EWMA Adaptive Thresholds vs. Kalman Filter in Python

July 16, 2026 9 min read

Prometheus Monitoring Signal Processing Python Machine Learning
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Ensemble Kalman Filter (EnKF): Theory and Python Implementation for High-Dimensional Data Assimilation

July 16, 2026 6 min read

Machine Learning Filtering Monte Carlo Method Python
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Measuring Kubernetes' Horizontal Pod Autoscaler (HPA) as a PID Control Loop: Comparing Overshoot and Settling Time Against Ratio Control

July 16, 2026 9 min read

Kubernetes Control Theory PID Python
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Hamiltonian Monte Carlo (HMC) in Python: Overcoming the Metropolis Algorithm's Weaknesses with Leapfrog Integration

July 15, 2026 14 min read

Machine Learning Python Algorithms
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GARCH(1,1) in Python: Modeling Volatility Clustering and Confirming the ARCH Effect with the Ljung-Box Test

July 15, 2026 14 min read

Statistics Python Data Visualization
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Post-Quantum Cryptography in Python: Learning With Errors (LWE), Regev Encryption, and Why It Resists Quantum Computers

July 15, 2026 19 min read

Algorithms Cryptography Python
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SHA-256 and HMAC in Python: The Merkle-Damgård Construction, Length-Extension Attacks, and RFC 4231 Verification

July 15, 2026 10 min read

Algorithms Cryptography Python
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Dissecting the TLS 1.3 Handshake in Python: ECDHE, the HKDF Key Schedule, and AEAD

July 15, 2026 14 min read

Algorithms Cryptography Python
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SVM Kernel Design in Python: Mercer's Theorem, Gram Matrix Positive-Definiteness, and Random Fourier Features

July 15, 2026 12 min read

Machine Learning Python Algorithms
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ARMA/ARIMA in State-Space Form: Kalman-Filter Maximum Likelihood Estimation, Reproducing statsmodels from Scratch

July 15, 2026 11 min read

Statistics Python Data Visualization
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The RLS Algorithm in Python: Recursive Least Squares, Its Equivalence to the Kalman Filter, and the Forgetting Factor

July 15, 2026 14 min read

Signal Processing Python Adaptive Filtering
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Nonlinear Kalman Smoothers in Python: Extended RTS Smoother and Unscented RTS Smoother

July 14, 2026 14 min read

Machine Learning Filtering Signal Processing Python
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Teager-Kaiser Energy Operator (TKEO) in Python: A Faster Alternative to the Hilbert Transform for Bearing Diagnostics

July 14, 2026 14 min read

Signal Processing Filtering Python
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CEEMDAN and the Marginal Hilbert Spectrum: Solving EEMD's Reconstruction Error and Mode Splitting, with Bearing Fault Diagnosis

July 14, 2026 11 min read

Signal Processing Mode Decomposition EMD CEEMDAN Python Anomaly Detection
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12 Recommended Books for Learning Signal Processing, Machine Learning, and Control in Python (2026, by Level)

July 11, 2026 2 min read

信号処理 機械学習 読書 Python
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Nyquist Plot, Root Locus, and Stability Margins in Python: Evaluating Closed-Loop Stability with Gain and Phase Margins

July 11, 2026 10 min read

制御 信号処理 周波数解析 Python
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Partial Autocorrelation (PACF) and AR Model Order Identification: Yule-Walker and Levinson-Durbin in Python

July 10, 2026 22 min read

Statistics Python
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MDCT (Modified Discrete Cosine Transform) and Filter Banks: TDAC, Perfect Reconstruction Theory, and Python Implementation

July 5, 2026 19 min read

Signal Processing Fourier Transform Python
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Digital Signatures in Python: ECDSA vs EdDSA vs RSA-PSS, Nonce Reuse Attacks, and RFC 6979

July 4, 2026 22 min read

Algorithm Cryptography Python
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Gaussian Process Regression in Practice: Kernel Design and Hyperparameter Optimization with scikit-learn

July 4, 2026 21 min read

Machine Learning Gaussian Process Bayesian Optimization Python
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Kalman Smoother Comparison: RTS vs Fixed-Lag vs Fixed-Point Smoothing in Python (Theory, Latency, and RMSE Benchmarks)

July 4, 2026 24 min read

Machine Learning Filtering Signal Processing Python
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AES and ChaCha20 in Python: Block Cipher Rounds, GF(2^8), AES-GCM vs ChaCha20-Poly1305, and Nonce Pitfalls

July 3, 2026 25 min read

Algorithm Cryptography Python
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Practical Spectrograms: STFT Window Size, Overlap Choice, and ShortTimeFFT Migration in SciPy

July 3, 2026 19 min read

Signal Processing Python
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Elliptic Curve Cryptography (ECC) in Python: Point Addition over Finite Fields, ECDLP, ECDH, ECDSA, and X25519

July 2, 2026 18 min read

Algorithm Cryptography Python
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Multirate Signal Processing in Python: Decimation, Interpolation, and Polyphase Filters

July 2, 2026 20 min read

Signal Processing Python
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Diffie-Hellman Key Exchange in Depth: Discrete Log, Safe Primes, MITM, and X25519 in Python

June 14, 2026 16 min read

Algorithm Cryptography Python
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Time Series Forecasting with Transformers in PyTorch: Attention and Positional Encoding Explained

June 14, 2026 19 min read

Transformer Time Series Attention Deep Learning Machine Learning PyTorch Python
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Cryptography Roadmap: Classical, Symmetric, RSA, Diffie-Hellman, Elliptic Curves, Hashing, Signatures, and TLS in Python

June 14, 2026 25 min read

Cryptography Python Learning Roadmap RSA Public Key Cryptography Elliptic Curve Cryptography Diffie-Hellman Hash Digital Signature
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Discrete Signal Processing Fundamentals Roadmap: Sampling, Interpolation, DFT, Z-Transform, and Autocorrelation

June 13, 2026 19 min read

Signal Processing DSP Python Learning Roadmap Sampling Theorem DFT Z-Transform
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Mode Decomposition with EMD, VMD, and SSA: Python Implementation and Comparison for Non-Stationary Signals

May 28, 2026 22 min read

Signal Processing Mode Decomposition EMD VMD SSA Python Time-Frequency Analysis
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Digital Signal Processing and Machine Learning Roadmap: 5-Hub Learning Path with scipy.signal/numpy.fft/pywt/sklearn

May 28, 2026 14 min read

Signal Processing Machine Learning Learning Roadmap Python Filter Design Time-Frequency
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Machine Learning Hub for Time-Series Forecasting, Classification, and Anomaly Detection in Python: When to Use k-means/GMM, Ensembles, LSTM, and Kalman Filters

May 25, 2026 16 min read

Machine Learning Time Series Clustering Ensemble Learning LSTM Anomaly Detection Python
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Time-Frequency Analysis Guide: Choosing FFT, STFT, Wavelet, and Hilbert Transform with Python

May 24, 2026 17 min read

FFT STFT Wavelet Hilbert Python spectrogram
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Digital Filter Design Guide: Selection, Comparison, and Python Implementation Hub

May 22, 2026 16 min read

Filtering Signal Processing Python Filter Design
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Monte Carlo Optimization (CEM/SA/GA/MPPI/PSO): Fundamentals, Comparison, and Python Implementation

May 22, 2026 14 min read

Optimization Monte Carlo Python Signal Processing Machine Learning
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Wavelet Packet Transform and Best Basis Selection: High-Resolution Time-Frequency Analysis with Python Implementation

May 22, 2026 17 min read

Wavelet Signal Processing Time-Frequency Analysis Python
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Bode Plot: Reading and Creating Frequency Response Diagrams with Python Implementation

May 21, 2026 20 min read

Filter Design Signal Processing Frequency Analysis Python
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Linear Predictive Coding (LPC): Theory and Python Implementation

May 6, 2026 18 min read

Signal Processing Python Speech Processing
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DTFT vs DFT vs FFT: Definitions, Relationships, and Python Implementation

May 5, 2026 13 min read

Signal Processing DSP Python
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Convolution and Correlation Fundamentals: Theory, Convolution Theorem, and Python Implementation

May 2, 2026 21 min read

Signal Processing Python Convolution Correlation
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Gaussian Process Regression: Fundamentals and Python Implementation

May 2, 2026 21 min read

Machine Learning Bayesian Optimization Python Gaussian Process
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Particle Swarm Optimization (PSO): Math and Python Implementation with Inertia Weight, Cognitive and Social Coefficients

May 1, 2026 20 min read

Optimization Python Metaheuristics
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Adaptive Filters: LMS and NLMS Algorithms — Theory and Python Implementation

May 1, 2026 19 min read

Signal Processing Python Adaptive Filter
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Signal Reconstruction and Interpolation: Sinc, Linear, and Spline in Python

April 30, 2026 19 min read

Signal Processing Python
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Discrete Cosine Transform (DCT): Theory, Fast Computation, and JPEG/Audio Compression

April 30, 2026 22 min read

Signal Processing Python Data Compression
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Independent Component Analysis (ICA): Blind Source Separation with Python

April 30, 2026 21 min read

Signal Processing Machine Learning Python
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Z-Transform and Digital Filter Design: Poles, Zeros, and Stability with Python — Transfer Function H(z) Worked Examples in scipy

April 30, 2026 21 min read

Signal Processing Filtering Python
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Nyquist-Shannon Sampling Theorem and Aliasing: A Complete Python Guide

April 30, 2026 24 min read

Signal Processing Python
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Phase Spectrum and Group Delay: Theory and Python Implementation

April 30, 2026 23 min read

Signal Processing Filtering Python
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Autocorrelation and Cross-Correlation: Theory and Python Implementation

April 29, 2026 23 min read

Signal Processing Python Time Series
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Cepstrum Analysis: Theory and Python Implementation

April 29, 2026 19 min read

Signal Processing Python Speech Processing
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Short-Time Fourier Transform (STFT): Theory and Python Implementation

April 29, 2026 15 min read

Signal Processing Python
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scipy.signal.hilbert in Python: Envelope Detection, AM/FM Demodulation, Bearing Fault Diagnostics

March 18, 2026 19 min read

Signal Processing Filtering Python
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LSTM for Time Series Forecasting: Theory and Python Implementation

March 17, 2026 21 min read

Python Machine Learning Statistics
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Bessel Filter Design Principles and Python Implementation — Flat Group Delay and Pulse Preservation with scipy.signal.bessel

March 16, 2026 13 min read

Filtering Signal Processing Python
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Elliptic Filter (Cauer Filter): Design Principles and Python Implementation

March 15, 2026 16 min read

Filter Design Signal Processing Python
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Chebyshev Filter Design: Theory and Python Implementation

March 14, 2026 18 min read

Signal Processing Python Algorithm
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Introduction to Probabilistic Data Structures: Bloom Filter and HyperLogLog in Python

March 13, 2026 21 min read

Algorithm Python Data Structure
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Python Type Hints Practical Guide: From Basics to mypy

March 13, 2026 16 min read

Python Programming
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Complementary Filter Theory and Python Implementation: Gyroscope and Accelerometer Sensor Fusion

March 13, 2026 19 min read

Filtering Signal Processing Python
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Highpass Filter Design: Theory and Python Implementation

March 13, 2026 16 min read

Signal Processing Python Algorithm
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Bandpass Filter Design: Theory and Python Implementation

March 12, 2026 17 min read

Signal Processing Python Algorithm
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Python Logging Module Practical Guide: Beyond print()

March 12, 2026 13 min read

Python Programming
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Next.js App Router + Prisma Practical Patterns: Type-Safe Database Operations

March 11, 2026 11 min read

Next.js Prisma TypeScript Web Development
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Efficient CSV File Processing in Python: csv, pandas, and polars Compared

March 11, 2026 20 min read

Python Data Processing
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Median Filter Theory and Python Implementation: Non-Linear Filter for Impulse Noise Removal

March 11, 2026 29 min read

Filtering Signal Processing
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Savitzky-Golay Filter: Theory and Python Implementation

March 10, 2026 23 min read

Filtering Signal Processing
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Adaptive Filters (LMS/RLS): Theory and Python Implementation

March 10, 2026 18 min read

Filtering Signal Processing
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Free Pomodoro Timer with Work Tracking and PiP Support

March 6, 2026 1 min read

Web App Productivity
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CalcBox - 61+ Free Online Calculators for Everyday Life

March 6, 2026 15 min read

Web App Calculator Tools Python
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DevToolBox - 85+ Free Online Developer Tools

March 6, 2026 11 min read

Programming Developer Tools Security
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Understanding Self-Attention from Scratch: Math and Python Implementation

February 28, 2026 14 min read

Deep Learning Machine Learning Python
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Notch Filter Design and Python Implementation: Removing Power Line Noise

February 28, 2026 17 min read

Signal Processing Filtering Python
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Time-Series Anomaly Detection: From Statistical Methods to Kalman Filter in Python

February 28, 2026 16 min read

Machine Learning Filtering Python Signal Processing
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Window Functions and Power Spectral Density (PSD): Theory and Python Implementation

February 28, 2026 18 min read

Signal Processing Python
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Support Vector Machines (SVM): Margin Maximization, Deriving the KKT Conditions and Dual Problem, and Python Implementation

February 26, 2026 13 min read

Machine Learning Python Algorithm
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ARIMA and SARIMA Theory and Python Implementation: statsmodels.tsa.arima.model with ACF/PACF for Time-Series Forecasting

February 26, 2026 18 min read

Statistics Python Data Visualization
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Markov Chain Monte Carlo (MCMC): Metropolis-Hastings and Gibbs Sampling

February 26, 2026 16 min read

Bayesian Statistics Monte Carlo Python
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From SGD to Adam: Evolution of Gradient-Based Optimization

February 26, 2026 16 min read

Machine Learning Optimization Python
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k-means and GMM (Gaussian Mixture Model) Theory, Comparison, and Python Implementation: sklearn.cluster.KMeans / sklearn.mixture.GaussianMixture / EM algorithm

February 26, 2026 19 min read

Machine Learning Python Algorithm
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Ensemble Learning: From Decision Trees to Random Forest and Gradient Boosting

February 26, 2026 14 min read

Machine Learning Python Algorithm
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Introduction to Wavelet Transform: Time-Frequency Analysis in Python (PyWavelets / pywt)

February 26, 2026 15 min read

Signal Processing Python Data Visualization
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Wiener Filter: Optimal Linear Filtering Theory and Python Implementation — SNR-Based Noise Reduction Design Example

February 26, 2026 17 min read

Filtering Python Signal Processing
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Zero Trust Architecture: Principles, Components, and Implementation

February 26, 2026 13 min read

Security Network
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Introduction to Asynchronous Programming with Python asyncio

February 26, 2026 14 min read

Python Async Programming
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Unscented Kalman Filter (UKF): Nonlinear State Estimation Theory and Python Implementation

February 26, 2026 19 min read

Filtering Python Algorithm
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Python Regular Expressions: Practical Guide from Basics to Performance Optimization and ReDoS Internals

February 26, 2026 11 min read

Python
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Simulated Annealing: Theory and Python Implementation

February 26, 2026 22 min read

Optimization Algorithm Python
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Butterworth Filter Design: Theory and Python Implementation

February 26, 2026 11 min read

Signal Processing Python Algorithm
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Git Branch Strategies: rebase vs merge and Team Workflows

February 26, 2026 14 min read

Git DevOps
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Local Development with Docker Compose: MySQL, Redis, and MinIO

February 26, 2026 13 min read

Docker Database DevOps
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OAuth 2.0 and OpenID Connect: Fundamentals of Authorization and Authentication

February 26, 2026 18 min read

Security Authentication Web
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Python Decorators: Mechanics and Practical Patterns

February 26, 2026 11 min read

Python Programming
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Genetic Algorithms: Fundamentals and Python Implementation

February 26, 2026 18 min read

Optimization Algorithm Python
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FIR vs IIR Filters: Characteristics, Design, and Python Implementation

February 26, 2026 17 min read

Signal Processing Python Algorithm
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PID Control in Python: Simulation and Tuning

February 25, 2026 29 min read

Control Python Simulation
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RSA Encryption Theory, Key Generation, Encryption, and Decryption in Python (pow, math.gcd, extended Euclidean, Miller-Rabin)

February 25, 2026 29 min read

Algorithm Cryptography Python
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Fast Fourier Transform (FFT): Theory and Python Implementation with scipy.fft and numpy.fft

February 25, 2026 12 min read

Signal Processing Python Algorithm
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Moving Average Filters Compared: SMA, WMA, and EMA in Python

February 25, 2026 18 min read

Filtering Signal Processing Python
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Extended Kalman Filter (EKF): Theory and Python Implementation

February 24, 2026 24 min read

Machine Learning Filtering Python
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Kalman Filter: Theory and Python Implementation

February 24, 2026 20 min read

Machine Learning Filtering Python
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Security Certification Comparison: CISSP vs Japan's Registered Information Security Specialist

February 23, 2026 3 min read

Security Certification
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Kalman Smoother (Rauch-Tung-Striebel / RTS): Forward-Backward Recursion and Python Implementation (numpy.linalg.inv)

February 23, 2026 22 min read

Machine Learning Filtering Signal Processing Python
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Python Progress Bars: tqdm.tqdm, tqdm.notebook, tqdm.auto, tqdm.pandas, and a From-Scratch Implementation

February 23, 2026 19 min read

Python Programming Tips
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Matplotlib Practical Tips: Publication-Quality Figures in Python (plt.rcParams, savefig, colormap, subplots, tight_layout)

February 23, 2026 17 min read

Python Matplotlib Data Visualization
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Particle Filter Python Implementation: Comparing Resampling Methods

February 23, 2026 22 min read

Machine Learning Filtering Monte Carlo Method Python
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Low-Pass Filter Design and Comparison: Moving Average, Butterworth, and Chebyshev

February 23, 2026 19 min read

Filtering Signal Processing Python
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Bayesian Optimization: Fundamentals and Python Implementation

February 23, 2026 14 min read

Machine Learning Optimization Bayesian Statistics Python
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MPPI (Model Predictive Path Integral): A Unified View with the Cross-Entropy Method

February 15, 2026 24 min read

Machine Learning Optimization Monte Carlo Method Control Python
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Cubature Kalman Filter (CKF): Theory and Python Implementation

February 15, 2026 25 min read

Machine Learning Filtering Python
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Resolving Timezone Mismatch Issues Between Prisma and MySQL

January 25, 2026 14 min read

Prisma MySQL Timezone JST Development
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Micro Hardening Training Participation Report

August 21, 2025 2 min read

Security
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Hackfes 2025 Participation Notes

July 19, 2025 5 min read

Security
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Notes from Day 1 of AWS JumpStart 2025

March 13, 2025 5 min read

AWS
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JAWS DAYS 2025 Event Report

March 2, 2025 3 min read

AWS
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Spending 180,000 Yen Out of Pocket to Take the CISSP Exam

November 9, 2024 2 min read

Security
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Shell Script to Detect Homebrew Packages with No Dependents

October 28, 2024 1 min read

Shell Shell Script macOS Tips
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Reading Notes: 'OSINT Practical Guide' - Fundamentals of Open Source Intelligence

August 29, 2024 2 min read

Security
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Comparing Major Security Models: Biba, Clark-Wilson, Brewer-Nash, and Bell-LaPadula

June 16, 2024 2 min read

Security
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CISSP Security Governance Prep: Untangling COBIT, ITIL, NIST, and Other Frequently Tested Frameworks

June 6, 2024 11 min read

Security Certification
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Transaction Isolation Levels and the Data Inconsistencies They Prevent

May 18, 2024 15 min read

DB Database Transaction PostgreSQL
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Handling Namespace Conflicts When Running Spark SQL Views in Parallel

May 3, 2024 2 min read

Spark SQL
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How to Pass the Registered Information Security Specialist (RISS) Exam: Self-Study Materials, Techniques, and Registration

May 3, 2024 4 min read

Security Certification
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Integrating TypeScript and React into a Hugo Theme

December 18, 2023 5 min read

Hugo TypeScript React Web Development
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Shell Script to Batch Convert Excel to CSV: Using the xlsx2csv Command, with an External-Command Startup Cost Benchmark

December 12, 2023 7 min read

Shell Script Excel CSV
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Managing Unified Git Commit Messages with Commitizen

December 8, 2023 12 min read

Git Development
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Generating Prometheus Metrics from Logs with mtail

November 24, 2023 5 min read

Monitoring Prometheus Logging
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Technical Challenges of Sharing prom-client Metrics Between Next.js App Router and Pages Router

November 24, 2023 12 min read

JavaScript Next.js Prometheus
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Diffie-Hellman Key Exchange Protocol: Theory and Python Implementation

September 6, 2023 18 min read

Algorithm Cryptography Python
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DS201 Study Notes: Cassandra Compaction

June 29, 2023 2 min read

Cassandra DataStax
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DS201 Study Notes: Cassandra NodeSync

June 29, 2023 2 min read

Cassandra DataStax
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DS201 Study Notes: Cassandra Write Path and Read Path

June 29, 2023 2 min read

Cassandra DataStax
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DS201 Study Notes: Cassandra Consistency Levels

June 25, 2023 3 min read

Cassandra DataStax
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DS201 Study Notes: Cassandra Hinted Handoff

June 25, 2023 2 min read

Cassandra DataStax
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DS201 Study Notes: Cassandra Read Repair

June 25, 2023 2 min read

Cassandra DataStax
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DS201 Study Notes: Cassandra Replication

June 25, 2023 4 min read

Cassandra DataStax Database
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DS201 Study Notes: Cassandra Snitches

June 24, 2023 2 min read

Cassandra DataStax
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How to Downgrade from iOS 17 Developer Beta to iOS 16 (iPhone 13)

June 18, 2023 2 min read

iPhone iOS
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DS201 Study Notes: Cassandra Gossip Protocol

June 10, 2023 2 min read

Cassandra DataStax
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DS201 Study Notes: Cassandra nodetool Commands

June 10, 2023 6 min read

Cassandra DataStax
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DS201 Study Notes: Cassandra Ring Architecture

June 10, 2023 4 min read

Cassandra DataStax
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DS201 Study Notes: Cassandra VNodes

June 10, 2023 2 min read

Cassandra DataStax
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DS201 Study Notes: Cassandra Clustering Columns

May 20, 2023 3 min read

Cassandra DataStax
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DS201 Study Notes: Using the Cassandra Python Driver

May 20, 2023 2 min read

Cassandra Python DataStax
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DS201 Study Notes: Basics of Cassandra Query Language (CQL)

May 16, 2023 2 min read

Cassandra CQL DataStax
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DS201 Study Notes: Cassandra Partitions

May 16, 2023 2 min read

Cassandra DataStax
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Installing and Starting Cassandra on macOS

May 16, 2023 5 min read

Cassandra macOS Database
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AWS Summit Tokyo 2023 Attendance Report

April 20, 2023 1 min read

AWS Event
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Email Security: Authentication and Encryption Technologies

March 28, 2023 23 min read

Security Email
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Challenge-Response Authentication

January 3, 2023 16 min read

Security Authentication
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Single Sign-On (SSO) and Identity Federation

January 3, 2023 2 min read

Security Authentication
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How to Use Vim: Mode Switching, Save/Quit, Movement & Editing Commands, and Recommended Plugins

December 30, 2022 4 min read

Vim Editor
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JavaScript Asynchronous Processing: From Callbacks to Promise and Async/Await

December 29, 2022 16 min read

JavaScript Asynchronous Processing
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Building a React/TypeScript Development Environment with Webpack and Babel

November 11, 2022 14 min read

JavaScript React TypeScript Webpack Babel
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Kubernetes Credentials and Context Management

September 4, 2022 2 min read

Kubernetes
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Default Namespaces in Kubernetes

September 1, 2022 2 min read

Kubernetes
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Kubernetes Resource Categories and Objects

September 1, 2022 3 min read

Kubernetes
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Dockerfile Key Instructions and Best Practices

August 31, 2022 14 min read

Docker Kubernetes
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Setting Up a Local Kubernetes Environment with Minikube

August 31, 2022 2 min read

Kubernetes Docker
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Building a Simple JSON Mock Server with Python

July 16, 2022 11 min read

Python Web Development Testing
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Multi-Hop SSH via a Bastion Host: The Complete Guide to ProxyJump, ProxyCommand, and ~/.ssh/config

July 16, 2022 7 min read

Linux SSH Networking
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Reparameterization Trick

February 6, 2022 14 min read

Machine Learning Deep Learning
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Frequency Characteristics of the Exponential Moving Average Filter

February 6, 2022 10 min read

Filtering Signal Processing
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SQL Table Joins: INNER, OUTER, and CROSS JOIN

December 30, 2021 3 min read

SQL Database
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Where Are Linux Logs? Key /var/log Files and Viewing Them with last, tail, and grep

December 30, 2021 2 min read

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