B. Kalem Machine learning for signals and scientific data

Machine Learning for Signals and Scientific Data


Batuhan Kalem1,2,*

1Department of Mathematics, Boğaziçi University
2Kandilli Observatory and Earthquake Research Institute (KOERI), Boğaziçi University
Istanbul, Türkiye contact@batuhankalem.com

Abstract

I am a fourth-year mathematics student at Boğaziçi University working on machine learning for signals, time series and other scientific data. My work spans generative models, deep architectures including graph neural networks, and probabilistic and physics-informed learning, with careful evaluation throughout. These methods are currently applied to seismic recordings at the Kandilli Observatory, where I build and evaluate models and the workflows around them. I also design and lead the practical coursework of MATH482 and build data solutions at Research İstanbul. The aim is to build models, test them honestly, and turn them into working systems.

Keywords: machine learning · generative models · diffusion and flow matching · graph neural networks · probabilistic learning · physics-informed neural networks · time series · seismology

*Correspondence: contact@batuhankalem.com. Code at github.com/Pancarsuyu; notebooks and competitions at kaggle.com/batuhankalem; profile at linkedin.com/in/batuhankalem.

1Research

My work is machine learning for signals, time series and other scientific data. Figure 1 gives an overview: the methods I work with, and the listed pieces of work in which each has been used. The current application domain is seismic recordings. At the Kandilli Observatory and Earthquake Research Institute (KOERI) I am a research assistant on TRACE,1TRACE project website: trace.bogazici.edu.tr. Its funding is noted in the Acknowledgements. where I develop and evaluate AI models for earthquake detection and location and build the scientific backend that connects data preparation, model training, inference and catalog analysis.

Methods

Generative

  • Diffusion modelsUsed in: generative models for seismic waveforms (Section 1.1); term project on latent diffusion (Appendix A).
  • Flow matchingCurrent work; write-ups to follow.
  • Variational autoencodersUsed in: MATH482 notebook on variational autoencoders (Appendix A).
  • GANsUsed in: term project on the StyleGAN2 latent space (Appendix A).

Architectures

  • CNNs and residual networksUsed in: MATH482 residual learning lab and assignment (Appendix A).
  • TransformersCurrent work; write-ups to follow.
  • Graph neural networksUsed in: GENIE on regional seismic networks (Section 1.2).

Probabilistic

  • Probabilistic neural networksUsed in: MATH482 material on probabilistic models and loss derivation (Appendix A).
  • Mixture density networksUsed in: MATH482 material on probabilistic models and loss derivation (Appendix A).

Physics-informed

  • Physics-informed neural networksCurrent work; write-ups to follow.

Language

  • Large language modelsUsed in: PatentAI (Section 2.2); Turkish LLM fine-tuning dataset (Section 2.3).

Sequential

  • Time-series modelsUsed in: inflation forecasting (Section 2.1).

Work

Research

  • Generative models for seismic waveformslatent diffusion · ESC 2026 [1] · §1.1Methods: diffusion models.
  • GENIE on regional seismic networksEGU 2025 [2] · §1.2Methods: graph neural networks.

Teaching, MATH482

  • Term project: latent diffusion and image editingAppendix AMethods: diffusion models.
  • Term project: StyleGAN2 latent spaceAppendix AMethods: GANs.
  • Smiling VAEnotebook · Appendix AMethods: variational autoencoders.
  • Residual learninglab and assignment · Table A1Methods: CNNs and residual networks.
  • Probabilistic NNs, mixture density networks, loss derivationlabs and assignments · Table A1Methods: probabilistic neural networks; mixture density networks.

Projects

  • PatentAI§2.2Methods: large language models.
  • Turkish LLM fine-tuning dataset§2.3Methods: large language models.
  • Inflation forecasting§2.1Methods: time-series models.

Figure 1. Overview of methods and work. Left: the methods I work with, grouped by family. Right: the work listed on this page, namely research (Section 1), projects (Section 2) and MATH482 teaching material (Appendix A). A line joins a method to a piece of work only where that work uses it. Methods marked with an open circle (flow matching, Transformers and physics-informed neural networks) are areas I currently work in; write-ups will follow. Point at or focus an item to highlight its connections; the arrow keys move between items.

1.1Generative modelling

I work with diffusion models, flow matching, variational autoencoders and GANs. In research, I work on conditional generative models for seismic waveform synthesis, including latent diffusion. The question is how the parameters of an event and the physical properties of a signal can inform both how waveforms are generated and how the generated waveforms are evaluated. High-resolution waveform generation for the Marmara region with conditional latent diffusion is the subject of an oral presentation at ESC 2026 in Istanbul [1]. In teaching, the MATH482 term projects explore the StyleGAN2 latent space and conditional latent diffusion for image editing, and a course notebook covers variational autoencoders (Appendix A).

1.2Learning on structured data

I work with convolutional and residual networks, Transformers, and graph neural networks. A seismic network is a set of sensors whose recordings have to be read together, which makes it a natural setting for graph neural networks. I adapt and evaluate GENIE, a graph neural network model, for regional seismic networks,2Code: a fork of GENIE at github.com/Pancarsuyu/GENIE. working on model training, inference efficiency, and comparison against observatory catalogs. AI-driven event detection and association for monitoring at KOERI is the subject of a contribution to the EGU General Assembly 2025 [2]. Residual learning is also one of the MATH482 topics (Table A1).

1.3Probabilistic and physics-informed learning

I work with probabilistic neural networks; with mixture density networks, which predict a full conditional distribution instead of a single value; and with physics-informed neural networks (PINNs). The first two, together with the derivation of loss functions, are part of the MATH482 practical material (Table A1). Physics-informed networks are part of my current work.

Across all of this the common requirement is evaluation: generated signals judged with physically informed criteria, detections compared against observatory catalogs, and coursework that ties each method to an experiment.

2Selected work

The two projects on seismic data are described in Sections 1.1 and 1.2. Three further pieces of work, on economic time series and language models, are listed here; all five appear in Figure 1.

2.1Machine learning for inflation forecasting — time series

A replication of an inflation forecasting study, extended with feature engineering and regime-aware models on macroeconomic time series.

2.2PatentAI — LLM applications

An LLM application for patent research and startup analysis. It combines tool calling, information retrieval and report generation behind a conversational interface.

2.3Turkish LLM fine-tuning dataset — language models

A Turkish question–answer dataset, co-created for the T3 AI Hackathon, with a workflow for generating synthetic data and assessing its quality.

3Teaching

I am a course assistant for MATH482, Machine Learning Methods and Neural Networks, at Boğaziçi University.3Fall 2025 and Fall 2026. I design and lead the practical coursework in deep learning, probabilistic modelling and generative AI, with the aim of connecting the mathematical foundations to implementation and to careful experimental evaluation. The 2025 lab and assignment notebooks, published on Kaggle, and the term projects are collected in Appendix A.

4Experience

4.1Research Assistant, TRACEJune 2026 – present

Boğaziçi University · Kandilli Observatory and Earthquake Research Institute (KOERI)

Developing and evaluating AI models for earthquake detection and location; building the scientific backend workflows that connect data preparation, model training, inference and catalog analysis (Section 1). Project website: trace.bogazici.edu.tr.

4.2Teaching Assistant, MATH482: Machine Learning Methods and Neural NetworksFall 2025, Fall 2026

Boğaziçi University

Designing and leading practical coursework in deep learning, probabilistic modelling and generative AI (Section 3).

4.3Data Analyst, Research İstanbulDecember 2023 – present

Developing data collection and analysis pipelines for research reports and publications. I contribute to Susam Bülten through data analysis, visualisation and technical support, including work on the Lahmacun Index.4Susam Bülten: susambulten.com. The Lahmacun Index: susambulten.com/lahmacun-endeksi-spotify-bulgulari.

4.4Internships

  • Campaign Management Intern, QNBAugust 2025 – May 2026
  • Digital Marketing & Data Analyst Intern, World Obesity CenterSeptember 2022 – August 2023Analysed advertising campaign data and supported audience research and search visibility.

5Education and recognition

5.1Education

B.S. in Mathematics, Boğaziçi University, 2021 – present (fourth year).

5.2Recognition

AlgoRun Hackathon (Invent.ai & Compec), second place, 2025.
Kaggle Competitions Expert: kaggle.com/batuhankalem.

Acknowledgements

TRACE is supported by Google.org through a $1 million grant (university announcement).

References

Conference contributions, numbered in order of citation.

  1. [1] Erdem Ata, Batuhan Kalem, Yusuf Sezer Car, Çağrı Diner, Gülüm Tanırcan, Nurcan Meral Özel, Yasin Arkan. High-Resolution Seismic Waveform Generation in the Marmara Region Using Conditional Latent Diffusion. 40th General Assembly of the European Seismological Commission (ESC 2026), Istanbul, 2026. Oral presentation, abstract #9688. esc2026.org/programme.
  2. [2] Nurcan Meral Özel et al. (including Batuhan Kalem). Artificial Intelligence-Driven Seismic Event Detection and Association for Enhanced Monitoring at KOERI. EGU General Assembly 2025, Vienna, 2025. doi: 10.5194/egusphere-egu25-11172.

ATeaching materials

Practical material for MATH482, Machine Learning Methods and Neural Networks, at Boğaziçi University (Section 3).

A.1Lab and assignment notebooks

The 2025 notebooks are public on Kaggle and are listed by topic in Table A1. Each topic pairs a lab with an assignment.

Table A1. MATH482 teaching materials, 2025: Kaggle notebooks by topic.

#TopicLabAssignment
1Numerical foundations Lab 1 Assignment 1
2Neural networks from scratch Lab 2 Assignment 2
3Applied machine learning Lab 3 Assignment 3
4Learning objectives and optimization (loss derivation) Lab 4 Assignment 4
5Probabilistic neural networks Lab 5 Assignment 5
6Mixture density networks Lab 6 Assignment 6
7Residual learning Lab 7 Assignment 7

A.2Term projects

Term projects in generative modelling. Exploring the StyleGAN2 latent space: the Z and W spaces compared, linear editing, and identity preservation. Latent diffusion and image editing: conditional diffusion in the StyleGAN2 latent space, with classifier-free guidance.

A.3Additional notebook

Variational autoencoders: Smiling VAE, a MATH482 course notebook on Kaggle.

Set in Computer Modern. Figure 1 is a schematic; its lines follow only the connections between methods and the work listed on this page.