# Weiqi Ji (季维奇)

Founder of SVD Lab. Previously, I was a Senior Research Scientist at Bosch and Apple, following postdoctoral research at MIT. I received my PhD from Tsinghua University.

My research focuses on scientific machine learning and uncertainty quantification, with an emphasis on learning physical dynamics, differentiable simulation and sensitivity analysis.

[LinkedIn](https://www.linkedin.com/in/weiqiji)

## Catalog

- [Research homepage](https://jiweiqi.github.io/): publication pages and research themes.
- [Structured metadata](https://jiweiqi.github.io/publications.json): titles, authors, publication types, DOI, abstracts, summaries, GitHub repositories and full-text locations.
- [BibTeX](https://jiweiqi.github.io/publications.bib): citations for the collection.
- [Markdown index](https://jiweiqi.github.io/publications.md): papers grouped by research topic.

## Full text

- [Kinetics parameter optimization of hydrocarbon fuels via neural ordinary differential equations](https://jiweiqi.github.io/papers/kinetics-neural-ode/index.md) | [text](https://jiweiqi.github.io/papers/kinetics-neural-ode/fulltext.txt) | [PDF](https://jiweiqi.github.io/papers/kinetics-neural-ode/paper.pdf) | [related code](https://github.com/DENG-MIT/ArrheniusOpt)
- [Autonomous kinetic modeling of biomass pyrolysis using chemical reaction neural networks](https://jiweiqi.github.io/papers/biomass-crnn/index.md) | [text](https://jiweiqi.github.io/papers/biomass-crnn/fulltext.txt) | [PDF](https://jiweiqi.github.io/papers/biomass-crnn/paper.pdf) | [GitHub](https://github.com/DENG-MIT/Biomass.jl)
- [SGD-based optimization in modeling combustion kinetics: Case studies in tuning mechanistic and hybrid kinetic models](https://jiweiqi.github.io/papers/sgd-kinetics/index.md) | [text](https://jiweiqi.github.io/papers/sgd-kinetics/fulltext.txt) | [PDF](https://jiweiqi.github.io/papers/sgd-kinetics/paper.pdf) | [GitHub](https://github.com/DENG-MIT/Arrhenius.jl)
- [Arrhenius.jl: A Differentiable Combustion Simulation Package](https://jiweiqi.github.io/papers/arrhenius-jl/index.md) | [text](https://jiweiqi.github.io/papers/arrhenius-jl/fulltext.txt) | [PDF](https://jiweiqi.github.io/papers/arrhenius-jl/paper.pdf) | [GitHub](https://github.com/DENG-MIT/Arrhenius.jl)
- [Autonomous Discovery of Unknown Reaction Pathways from Data by Chemical Reaction Neural Network](https://jiweiqi.github.io/papers/crnn/index.md) | [text](https://jiweiqi.github.io/papers/crnn/fulltext.txt) | [PDF](https://jiweiqi.github.io/papers/crnn/paper.pdf) | [GitHub](https://github.com/DENG-MIT/CRNN)
- [Data-Driven Approaches to Learn HyChem Models](https://jiweiqi.github.io/papers/hychem/index.md) | [text](https://jiweiqi.github.io/papers/hychem/fulltext.txt) | [PDF](https://jiweiqi.github.io/papers/hychem/paper.pdf) | [GitHub](https://github.com/DENG-MIT/Arrhenius.jl)
- [Inference of cell dynamics on perturbation data using adjoint sensitivity](https://jiweiqi.github.io/papers/cellbox-adjoint/index.md) | [text](https://jiweiqi.github.io/papers/cellbox-adjoint/fulltext.txt) | [PDF](https://jiweiqi.github.io/papers/cellbox-adjoint/paper.pdf) | [GitHub](https://github.com/jiweiqi/CellBox.jl)
- [KiNet: A Deep Neural Network Representation of Chemical Kinetics](https://jiweiqi.github.io/papers/kinet/index.md) | [text](https://jiweiqi.github.io/papers/kinet/fulltext.txt) | [PDF](https://jiweiqi.github.io/papers/kinet/paper.pdf)
- [Neural Differential Equations for Inverse Modeling in Model Combustors](https://jiweiqi.github.io/papers/inverse-combustors/index.md) | [text](https://jiweiqi.github.io/papers/inverse-combustors/fulltext.txt) | [PDF](https://jiweiqi.github.io/papers/inverse-combustors/paper.pdf) | [GitHub](https://github.com/DENG-MIT/NN-PSR)
- [Stiff neural ordinary differential equations](https://jiweiqi.github.io/papers/stiff-neural-ode/index.md) | [text](https://jiweiqi.github.io/papers/stiff-neural-ode/fulltext.txt) | [PDF](https://jiweiqi.github.io/papers/stiff-neural-ode/paper.pdf) | [GitHub](https://github.com/DENG-MIT/StiffNeuralODE)
- [Stiff-PINN: Physics-Informed Neural Network for Stiff Chemical Kinetics](https://jiweiqi.github.io/papers/stiff-pinn/index.md) | [text](https://jiweiqi.github.io/papers/stiff-pinn/fulltext.txt) | [PDF](https://jiweiqi.github.io/papers/stiff-pinn/paper.pdf) | [GitHub](https://github.com/DENG-MIT/Stiff-PINN)
- [Kinetic subspace investigation using neural network for uncertainty quantification in nonpremixed flamelets](https://jiweiqi.github.io/papers/flamelet-subspace/index.md) | [text](https://jiweiqi.github.io/papers/flamelet-subspace/fulltext.txt) | [PDF](https://jiweiqi.github.io/papers/flamelet-subspace/paper.pdf)
- [Using shock tube species time-histories in Bayesian parameter estimation: Effective independent-data number and target selection](https://jiweiqi.github.io/papers/shock-tube-bayes/index.md) | [text](https://jiweiqi.github.io/papers/shock-tube-bayes/fulltext.txt) | [PDF](https://jiweiqi.github.io/papers/shock-tube-bayes/paper.pdf)
- [Uncertainty analysis in mechanism reduction via active subspace and transition state analyses](https://jiweiqi.github.io/papers/mechanism-reduction-uq/index.md) | [text](https://jiweiqi.github.io/papers/mechanism-reduction-uq/fulltext.txt) | [PDF](https://jiweiqi.github.io/papers/mechanism-reduction-uq/paper.pdf) | [GitHub](https://github.com/SuXY15/CanteraUq)
- [Dependence of kinetic sensitivity direction in premixed flames](https://jiweiqi.github.io/papers/premixed-sensitivity/index.md) | [text](https://jiweiqi.github.io/papers/premixed-sensitivity/fulltext.txt) | [PDF](https://jiweiqi.github.io/papers/premixed-sensitivity/paper.pdf)
- [Evolution of sensitivity directions during autoignition](https://jiweiqi.github.io/papers/ignition-sensitivity/index.md) | [text](https://jiweiqi.github.io/papers/ignition-sensitivity/fulltext.txt) | [PDF](https://jiweiqi.github.io/papers/ignition-sensitivity/paper.pdf) | [GitHub](https://github.com/jiweiqi/IgnSens)
- [Quantifying kinetic uncertainty in turbulent combustion simulations using active subspaces](https://jiweiqi.github.io/papers/turbulent-uq/index.md) | [text](https://jiweiqi.github.io/papers/turbulent-uq/fulltext.txt) | [PDF](https://jiweiqi.github.io/papers/turbulent-uq/paper.pdf) | [related code](https://github.com/DENG-MIT/ArrheniusActiveSubspace)
- [Uncertainty Propagation in Deep Neural Network Using Active Subspace](https://jiweiqi.github.io/papers/neural-network-uq/index.md) | [text](https://jiweiqi.github.io/papers/neural-network-uq/fulltext.txt) | [PDF](https://jiweiqi.github.io/papers/neural-network-uq/paper.pdf) | [GitHub](https://github.com/jiweiqi/nnsubspace)
- [Shared low-dimensional subspaces for propagating kinetic uncertainty to multiple outputs](https://jiweiqi.github.io/papers/shared-subspaces/index.md) | [related code](https://github.com/DENG-MIT/ArrheniusActiveSubspace)
- [Propagation of Kinetic Uncertainty through Surrogate Subspace in Combustion Simulations](https://jiweiqi.github.io/papers/surrogate-subspace/index.md)
- [Machine learning for combustion](https://jiweiqi.github.io/papers/machine-learning-combustion/index.md)
- [Machine learning model to project the impact of COVID-19 on US motor gasoline demand](https://jiweiqi.github.io/papers/mobility-demand/index.md) | [text](https://jiweiqi.github.io/papers/mobility-demand/fulltext.txt) | [PDF](https://jiweiqi.github.io/papers/mobility-demand/paper.pdf) | [GitHub](https://github.com/jiweiqi/covid19-mobility)
- [Ignition delay measurements of light naphtha: A fully blended low octane fuel](https://jiweiqi.github.io/papers/naphtha-ignition/index.md)
- [Measurement of reaction rate constants using RCM: A case study of decomposition of dimethyl carbonate to dimethyl ether](https://jiweiqi.github.io/papers/rcm-rate-constants/index.md)
- [On the crossover temperature and lower turnover state in the NTC regime](https://jiweiqi.github.io/papers/ntc-lower-turnover/index.md)
- [First-stage ignition delay in the negative temperature coefficient behavior: Experiment and simulation](https://jiweiqi.github.io/papers/first-stage-ntc/index.md)
- [On the controlling mechanism of the upper turnover states in the NTC regime](https://jiweiqi.github.io/papers/ntc-upper-turnover/index.md) | [text](https://jiweiqi.github.io/papers/ntc-upper-turnover/fulltext.txt) | [PDF](https://jiweiqi.github.io/papers/ntc-upper-turnover/paper.pdf)
- [Intermediate species measurement during iso-butanol auto-ignition](https://jiweiqi.github.io/papers/isobutanol-intermediates/index.md) | [GitHub](https://github.com/jiweiqi/Isobutanol_Mechanism)

PDF text extraction may lose mathematical notation and table layout. Consult the PDF when studying equations, figures or tables. Publication type and preprint identifiers are recorded separately in the catalog.