Ricardo Marquez, Ph.D.

Physical Systems Modeling · Probabilistic Reasoning · Scientific Software

I build computational tools for understanding complex physical systems under uncertainty.

My work spans power systems, weather and environmental modeling, forecasting, engineering simulation and production software. I am drawn to problems where physical models, imperfect measurements, uncertain operating conditions and computational limits all have to be brought together to support an engineering decision.

  • Power systems
  • Data centers
  • Weather
  • Risk & uncertainty

TERRA Selected work LinkedIn Contact

What I work on

Probabilistic physical systems

Models that combine physical constraints with uncertainty in operating conditions, component states, parameters and measurements.

Probabilistic inference · uncertainty quantification · risk analysis · Bayesian reasoning · scenario analysis

Power & energy systems

Modeling and software for transmission systems, dynamic line ratings, grid operations, renewable energy, forecasting and reliability.

DLR/AAR · transmission · weather–grid interaction · contingency risk · EMS integration

Engineering simulation

Physics-based modeling of interconnected systems: thermal, fluid, environmental and energy.

Conservation laws · thermal systems · CFD · hydrology · physical simulation

Scientific software

Turning mathematical and engineering models into software that engineers and operators can actually use.

Python · Java/Spring · TypeScript/Angular · MATLAB · PostgreSQL/PostGIS · AWS · Docker

Featured project

TERRA — probabilistic reasoning for complex physical systems

TERRA is an experimental computational framework I have been developing to explore how physical simulation and probabilistic inference can be combined for engineering systems operating under uncertainty.

Traditional analysis asks

What happens under this scenario?

TERRA explores

Given what we know now, what states of the system are plausible, what could fail, how likely are those outcomes, and what observation would help us understand the system better?

TERRA represents uncertain physical systems as graphical probabilistic models coupled to physical constraints and engineering solvers, so the conservation laws and the uncertainty live in one structure.

Questions TERRA explores

Risk

What can fail, how likely is it, and what are the consequences?

Diagnosis

Which component, parameter or measurement best explains what we observe?

State estimation

What is probably happening where we cannot measure directly?

Attribution

Which uncertainties contribute most to system risk?

Experiment design

What should we measure next to reduce uncertainty most?

Counterfactuals

How would risk change under a different operating condition or intervention?

Application areas

Electric power systems

Probabilistic contingency analysis and physical risk assessment under uncertainty in weather, equipment availability, operating state, topology, ratings and measurements.

  • Which combinations of uncertain states actually drive system risk?
  • How does new evidence change contingency probabilities?
  • Can graphical structure reduce repeated physical simulation?
  • How should uncertainty in line ratings propagate into system-level risk?

Data centers

Probabilistic reasoning over interconnected power, cooling, thermal, compute and sensor systems.

  • Is abnormal cooling behavior degradation, operating conditions, or sensor bias?
  • What physical state best explains the telemetry we see?
  • What is the probability of a thermal or power constraint violation?
  • Which measurement would best separate competing explanations?

Selected TERRA studies

Each study is runnable, with its numbers read from committed results.

Twelve possible culprits, one telling measurement

Choosing the measurement that settles a diagnosis

A chilled-water loop serving about 860 kW of server heat looks far less efficient than it should, and twelve explanations — real faults and lying meters alike — could account for it. On the first five noisy readings the true cause, a return-temperature sensor reading low, ranked only third at about 11 %. TERRA recommended one specific follow-up check, an independent load heat audit; after it the true cause ranked first at about 57 %, a jump of roughly 46 points from a single measurement.

Demonstrates: evidence conditioning · Bayesian diagnosis · sensor uncertainty · experiment design

When a bad sensor looks normal

Finding measurement problems that threshold rules miss

Four scenarios were built in which one channel is corrupted by too little to trip its alarm, against a truth whose physics deliberately differs from the model used to recover it. TERRA ranked the corrupted channel first in 4 of 4 scenarios, against 2 of 4 for a peer-comparison baseline and 0 of 4 for alarm thresholds. The reconstructed replacement value beat the bad reading in every case, cutting the error by 26 % to 85 %.

Demonstrates: sensor diagnosis · latent-state inference · virtual sensing

Probabilistic grid contingency analysis

Combinatorial uncertainty in transmission systems

Probabilistic contingency analysis on standard power-system test networks, examining how graphical structure, physical separators, probability-ordered enumeration and selective physical simulation affect computational cost and the accuracy of the inference.

Demonstrates: power flow · N−k contingencies · rare-event risk · graphical factorization · scalable simulation

More studies and benchmarks →

Books

A general text states the method; five domain editions teach the same method with that domain's own examples and case studies. All are free to read, and every number in them is generated from a committed result.

Probabilistic Modeling of Boundary-Exchanging Physical Systems the general text PDF, 405 pp
Probabilistic Modeling of Power Systems transmission and dispatch PDF, 445 pp
Probabilistic Modeling of Water Distribution Networks PDF, 386 pp
Probabilistic Modeling of District Heating and Cooling Networks PDF, 369 pp
Probabilistic Modeling of Data Centers cooling, capacity and diagnosis PDF, 390 pp
Probabilistic Modeling of Battery Energy Storage Systems preview, Parts I–III PDF, 227 pp

Working drafts, revised as the underlying studies land.

Experience

Software Solution Architect / Modeling Engineer

WindSim Power / Pitch Aeronautics · 2019–present

Engineering software and modeling for electric transmission, centered on weather-informed dynamic line ratings and grid operations.

  • Dynamic and ambient-adjusted line-rating systems
  • Weather modeling and forecasting
  • Transmission sensor integration
  • REST services and operational dashboards
  • EMS and utility-system integration
  • Cloud and on-premise deployment
  • Utility DLR/AAR pilot projects

Project Engineer / Scientist

GEI Consultants

Hydrologic and environmental modeling, flood forecasting, emergency-response software, geospatial analysis and engineering applications.

Senior Scientist

Forecast Energy

Electric-load and solar-power forecasting models, data pipelines and operational forecasting systems.

Research

University of California, Merced

Solar irradiance forecasting, satellite image processing, radiation heat transfer, numerical modeling and scientific computing.

Technical background

Physical modelingPower systems, thermal systems, hydrology, CFD, heat transfer, weather
Probabilistic modelingBayesian inference, graphical models, uncertainty quantification, Monte Carlo, probabilistic risk
Scientific computingPython, MATLAB, C/C++, Fortran
Software engineeringJava, Spring, REST APIs, TypeScript, Angular
DataPostgreSQL, PostGIS, time series, geospatial data
InfrastructureAWS, Docker, Linux, Tomcat
EnergyTransmission, DLR/AAR, weather integration, forecasting, EMS

Education

  • Ph.D., Mechanical Engineering — University of California, Merced, 2012
  • B.S., Environmental Engineering — University of California, Merced, 2008

PMP · iSAQB CPSA-F · CompTIA Security+ · ISO 27001 Lead Implementer · EC-Council DevSecOps

About

I am an engineer and software developer interested in computational problems at the boundary between physical modeling, probability and decision-making.

My career has moved across weather forecasting, hydrology, renewable-energy forecasting, transmission systems and engineering software. The common thread has been building models and software that turn incomplete physical information into useful engineering decisions.

More recently I have been exploring probabilistic physical-system reasoning through TERRA, particularly for electric grids and data-center infrastructure.

I enjoy problems that require moving between equations, simulation, data, software architecture and the engineering question that ultimately needs to be answered.

Contact

Questions about the method, corrections to the books, or work you think this fits — all welcome.

rmarquez123@gmail.com