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Agram, Nacira, Associate professorORCID iD iconorcid.org/0000-0003-1662-0215
Publications (10 of 38) Show all publications
Agram, N., Benth, F. E., Pucci, G. & Rems, J. (2026). A deep learning approach to renewable capacity installation under jump uncertainty. Mathematics and Computers in Simulation, 250, 152-177
Open this publication in new window or tab >>A deep learning approach to renewable capacity installation under jump uncertainty
2026 (English)In: Mathematics and Computers in Simulation, ISSN 0378-4754, E-ISSN 1872-7166, Vol. 250, p. 152-177Article in journal (Refereed) Published
Abstract [en]

We study a stochastic model for the installation of renewable energy capacity under demand uncertainty and jump driven dynamics. The system is governed by a multidimensional Ornstein–Uhlenbeck (OU) process driven by a subordinator, capturing abrupt variations in renewable generation and electricity load. Installation decisions are modeled through control actions that increase capacity in response to environmental and economic conditions. We consider two distinct solution approaches. First, we implement a structured threshold based control rule, where capacity is increased proportionally when the stochastic capacity factor falls below a fixed level. This formulation leads to a nonlinear partial integro-differential equation (PIDE), which we solve by reformulating it as a backward stochastic differential equation with jumps. We extend the DBDP solver in Huré et al. (2020) to the pure jump setting, employing a dual neural network architecture to approximate both the value function and the jump sensitivity. Second, to benchmark the performance of the first approach, we propose a deep control algorithm that directly learns a state and time dependent feedback threshold policy by minimizing the expected cost functional using neural networks. This approach preserves the threshold based structure while allowing the threshold to adapt dynamically to the evolving system state, enabling more flexible and responsive interventions. Numerical experiments on calibrated data highlight the strengths of both methods. While the threshold based BSDE approach offers interpretability and tractability, the deep control strategy achieves improved performance through flexibility in capacity allocation. Together, these tools provide a robust framework for decision support in long term renewable energy expansion under uncertainty.

Place, publisher, year, edition, pages
Elsevier BV, 2026
Keywords
BSDEs, Capacity installation, Deep learning, Jump diffusion, Optimal stochastic control, Renewable energy expansion, Threshold control
National Category
Computational Mathematics Control Engineering
Identifiers
urn:nbn:se:kth:diva-384812 (URN)10.1016/j.matcom.2026.06.024 (DOI)2-s2.0-105042678051 (Scopus ID)
Note

Not duplicate with diva 2025302

QC 20260703

Available from: 2026-07-03 Created: 2026-07-03 Last updated: 2026-07-03Bibliographically approved
Agram, N. & Pucci, G. (2026). Deep BSVIEs parametrization and learning-based applications. Neural Networks, 198, 108712
Open this publication in new window or tab >>Deep BSVIEs parametrization and learning-based applications
2026 (English)In: Neural Networks, ISSN 0893-6080, E-ISSN 1879-2782, Vol. 198, p. 108712-Article in journal (Refereed) Published
Abstract [en]

We study the numerical approximation of backward stochastic Volterra integral equations (BSVIEs) and their reflected extensions, which naturally arise in problems with time inconsistency, path dependent preferences, and recursive utilities with memory. These equations generalize classical BSDEs by involving two dimensional time structures and more intricate dependencies. We begin by developing a well posedness and measurability framework for BSVIEs in product probability spaces. Our approach relies on a representation of the solution as a parametrized family of backward stochastic equations indexed by the initial time, and draws on results of Stricker and Yor to ensure that the two parameter solution is well defined in a joint measurable sense. We then introduce a discrete time learning scheme based on a recursive backward representation of the BSVIE, combining the discretization of Hamaguchi and Taguchi with deep neural networks. A detailed convergence analysis is provided, generalizing the framework of deep BSDE solvers to the two dimensional BSVIE setting. Finally, we extend the solver to reflected BSVIEs, motivated by applications in delayed recursive utility with lower constraints.

Place, publisher, year, edition, pages
Elsevier BV, 2026
Keywords
BSVIEs, Deep learning, Neural network solvers, RBSVIEs, Stricker-Yor measurability
National Category
Computational Mathematics Probability Theory and Statistics Other Mathematics
Identifiers
urn:nbn:se:kth:diva-378534 (URN)10.1016/j.neunet.2026.108712 (DOI)001695064200001 ()41707458 (PubMedID)2-s2.0-105032249435 (Scopus ID)
Note

Not duplicate with DiVA 1982180

QC 20260327

Available from: 2026-03-27 Created: 2026-03-27 Last updated: 2026-03-27Bibliographically approved
Agram, N., Arharas, I., Pucci, G. & Rems, J. (2026). Deep Learning for Energy Market Contracts: Dynkin Game with Doubly RBSDEs\ast. SIAM Journal on Financial Mathematics, 17(3), 841-876
Open this publication in new window or tab >>Deep Learning for Energy Market Contracts: Dynkin Game with Doubly RBSDEs\ast
2026 (English)In: SIAM Journal on Financial Mathematics, E-ISSN 1945-497X, Vol. 17, no 3, p. 841-876Article in journal (Refereed) Published
Abstract [en]

We formulate a Contract for Difference (CfD) with early exit options as a two-player zero-sum Dynkin game, capturing the strategic interaction between an electricity producer and a regulatory authority. The payoff structure includes running revenues, early termination penalties, and a terminal settlement, while the underlying electricity prices follow mean-reverting dynamics. The value of the game and the associated feedback optimal stopping rules are characterized through a doubly reflected backward stochastic differential equation (DRBSDE). In addition, we provide a structural characterization of the reflection mechanism, showing how the cumulative penalty processes are generated by the interaction between the value process and the time dependent barriers. To approximate the solution of the DRBSDE, we propose a learning-based numerical method that combines time discretization with neural network approximations of the backward components along simulated price trajectories. The approach avoids explicit state space discretization, accommodates time dependent barriers, and is applicable in moderately high-dimensional settings. A convergence result is established to justify the link between the continuous-time formulation and its numerical approximation. The proposed Deep DRBSDE solver is illustrated on a CfD model driven by 24-dimensional mean-reverting electricity prices representing multiple European market zones. In addition, a symmetric benchmark Dynkin game in dimension 20 and a mean-field extension are considered to assess the validity of the solver in controlled settings. The numerical results demonstrate stable training behavior and a consistent approximation of the contract value and optimal stopping regions across the considered examples.

Place, publisher, year, edition, pages
Society for Industrial & Applied Mathematics (SIAM), 2026
Keywords
Dynkin game, contract for difference, deep learning, doubly reflected BSDEs
National Category
Computer Sciences Mathematical sciences
Identifiers
urn:nbn:se:kth:diva-388217 (URN)10.1137/25M1743089 (DOI)001838255000006 ()2-s2.0-105048646923 (Scopus ID)
Note

QC 20260918

Available from: 2026-09-18 Created: 2026-09-18 Last updated: 2026-09-18Bibliographically approved
Agram, N., Bachir Cherif, K. & Rognlien Dahl, K. (2026). Stochastic Maximum Principle with Default. Applied mathematics and optimization, 93(3), Article ID 72.
Open this publication in new window or tab >>Stochastic Maximum Principle with Default
2026 (English)In: Applied mathematics and optimization, ISSN 0095-4616, E-ISSN 1432-0606, Vol. 93, no 3, article id 72Article in journal (Refereed) Published
Abstract [en]

We study stochastic control problems in a financial market subject to default risk, modeled via a progressive enlargement of filtration. The default event is represented by a random time, and the associated information flow is incorporated through an enlarged filtration framework. We establish a stochastic maximum principle for controlled diffusion processes with a single jump at the default time. The approach relies on the martingale representation under the enlarged filtration, which allows us to derive the adjoint equations and characterize necessary optimality conditions. The presence of default introduces additional terms in both the state dynamics and the adjoint processes, reflecting the impact of jump risk and information flow on optimal strategies. We apply the theoretical results to two explicitly solvable portfolio optimization problems under default risk. In particular, we obtain closed form expressions for the optimal controls in both the logarithmic and exponential utility cases. We further analyze how the default mechanism influences optimal strategies through the filtration structure and model parameters. These results contribute to a deeper understanding of optimal decision making in the presence of random time events.

Place, publisher, year, edition, pages
Springer Nature, 2026
Keywords
Backward stochastic differential equations with default, Single jump, Stochastic maximum principle
National Category
Probability Theory and Statistics Fluid Mechanics
Identifiers
urn:nbn:se:kth:diva-381074 (URN)10.1007/s00245-026-10435-x (DOI)001741230900002 ()2-s2.0-105036211266 (Scopus ID)
Note

QC 20260518

Available from: 2026-05-18 Created: 2026-05-18 Last updated: 2026-05-18Bibliographically approved
Agram, N., Espen Benth, F., Pucci, G. & Rems, J. (2025). A Deep Learning Approach to Renewable Capacity Installation under Jump Uncertainty.
Open this publication in new window or tab >>A Deep Learning Approach to Renewable Capacity Installation under Jump Uncertainty
2025 (English)Manuscript (preprint) (Other academic)
Abstract [en]

We study a stochastic model for the installation of renewable energy capacity under demand uncertainty and jump driven dynamics. The system is governed by a multidimensional Ornstein-Uhlenbeck (OU) process driven by a subordinator, capturing abrupt variations in renewable generation and electricity load. Installation decisions are modeled through control actions that increase capacity in response to environmental and economic conditions. We consider two distinct solution approaches. First, we implement a structured threshold based control rule, where capacity is increased proportionally when the stochastic capacity factor falls below a fixed level. This formulation leads to a nonlinear partial integro-differential equation (PIDE), which we solve by reformulating it as a backward stochastic differential equation with jumps. We extend the DBDP solver in [15] to the pure jump setting, employing a dual neural network architecture to approximate both the value function and the jump sensitivity. Second, we propose a fully data driven deep control algorithm that directly learns the optimal feedback policy by minimizing the expected cost functional using neural networks. This approach avoids assumptions on the form of the control rule and enables adaptive interventions based on the evolving system state. Numerical experiments highlight the strengths of both methods. While the threshold based BSDE approach offers interpretability and tractability, the deep control strategy achieves improved performance through flexibility in capacity allocation. Together, these tools provide a robust framework for decision support in long term renewable energy expansion under uncertainty

Keywords
Capacity installation; Renewable energy expansion; Jump diffusion; BSDEs; Deep learning; Optimal stochastic control; Threshold control.
National Category
Computational Mathematics
Identifiers
urn:nbn:se:kth:diva-374875 (URN)10.48550/arXiv.2509.12364 (DOI)
Note

QC 20260107

Available from: 2026-01-06 Created: 2026-01-06 Last updated: 2026-01-12Bibliographically approved
Agram, N., Øksendal, B., Proske, F. & Tymoshenko, O. (2025). A Kalman filter for linear systems driven by time-space Brownian sheet. Stochastics: An International Journal of Probablitiy and Stochastic Processes, 1-22
Open this publication in new window or tab >>A Kalman filter for linear systems driven by time-space Brownian sheet
2025 (English)In: Stochastics: An International Journal of Probablitiy and Stochastic Processes, ISSN 1744-2508, E-ISSN 1744-2516, p. 1-22Article in journal (Refereed) Epub ahead of print
Abstract [en]

We study a linear filtering problem where the signal and observation processes are described as solutions of linear stochastic differential equations driven by time-space Brownian sheets. We derive a stochastic integral equation for the conditional value of the signal given the observation. This can be considered a time-space analogue of the classical Kalman filter. The result is illustrated with examples of the filtering problem involving noisy observations of a constant and noisy observations of the Brownian sheet.

Place, publisher, year, edition, pages
Informa UK Limited, 2025
Keywords
conditional expectation, Filtering, Kalman type filter, linear stochastic differential equations, Riccati equation, time-space Brownian sheets
National Category
Probability Theory and Statistics Control Engineering
Identifiers
urn:nbn:se:kth:diva-370092 (URN)10.1080/17442508.2025.2541059 (DOI)001562623800001 ()2-s2.0-105015207656 (Scopus ID)
Note

QC 20250919

Available from: 2025-09-19 Created: 2025-09-19 Last updated: 2025-12-30Bibliographically approved
Gharsa, O., Touba, M. M., Boumehraz, M. & Agram, N. (2025). Autonomous Vision-Based Object Detection and Tracking System for Quadrotor Unmanned Aerial Vehicles. Sensors, 25(20), Article ID 6403.
Open this publication in new window or tab >>Autonomous Vision-Based Object Detection and Tracking System for Quadrotor Unmanned Aerial Vehicles
2025 (English)In: Sensors, E-ISSN 1424-8220, Vol. 25, no 20, article id 6403Article in journal (Refereed) Published
Abstract [en]

This paper introduces an autonomous vision-based tracking system for a quadrotor unmanned aerial vehicle (UAV) equipped with an onboard camera, designed to track a maneuvering target without external localization sensors or GPS. Accurate capture of dynamic aerial targets is essential to ensure real-time tracking and effective management. The system employs a robust and computationally efficient visual tracking method that combines HSV filter detection with a shape detection algorithm. Target states are estimated using an enhanced extended Kalman filter (EKF), providing precise state predictions. Furthermore, a closed-loop Proportional-Integral-Derivative (PID) controller, based on the estimated states, is implemented to enable the UAV to autonomously follow the moving target. Extensive simulation and experimental results validate the system’s ability to efficiently and reliably track a dynamic target, demonstrating robustness against noise, light reflections, or illumination interference, and ensure stable and rapid tracking using low-cost components.

Place, publisher, year, edition, pages
MDPI AG, 2025
Keywords
computer vision, moving object tracking, object detection, state estimation, unmanned aerial vehicles
National Category
Control Engineering Computer graphics and computer vision Robotics and automation
Identifiers
urn:nbn:se:kth:diva-372573 (URN)10.3390/s25206403 (DOI)001602810100001 ()41157457 (PubMedID)2-s2.0-105020158831 (Scopus ID)
Note

QC 20251110

Available from: 2025-11-10 Created: 2025-11-10 Last updated: 2025-11-10Bibliographically approved
Agram, N. & Pucci, G. (2025). Deep BSVIEs Parametrization and Learning-Based Applications.
Open this publication in new window or tab >>Deep BSVIEs Parametrization and Learning-Based Applications
2025 (English)In: Article in journal (Refereed) Submitted
National Category
Computational Mathematics
Identifiers
urn:nbn:se:kth:diva-366385 (URN)
Note

QC 20250804

Available from: 2025-07-07 Created: 2025-07-07 Last updated: 2026-01-12Bibliographically approved
Agram, N. & Rems, J. (2025). Deep learning for conditional McKean–Vlasov jump diffusions. Systems & control letters (Print), 201, Article ID 106100.
Open this publication in new window or tab >>Deep learning for conditional McKean–Vlasov jump diffusions
2025 (English)In: Systems & control letters (Print), ISSN 0167-6911, E-ISSN 1872-7956, Vol. 201, article id 106100Article in journal (Refereed) Published
Abstract [en]

The current paper focuses on using deep learning methods to optimize the control of conditional McKean–Vlasov jump diffusions. We begin by exploring the dynamics of multi-particle jump-diffusion and presenting the propagation of chaos. The optimal control problem in the context of conditional McKean–Vlasov jump-diffusion is introduced along with the verification theorem (HJB equation). A linear quadratic conditional mean-field (LQ CMF) is discussed to illustrate these theoretical concepts. Then, we introduce a deep-learning algorithm that combines neural networks for optimization with path signatures for conditional expectation estimation. The algorithm is applied to practical examples, including LQ CMF and interbank systemic risk, and we share the resulting numerical outcomes.

Place, publisher, year, edition, pages
Elsevier BV, 2025
Keywords
Common noise, Deep learning, McKean–Vlasov jump diffusion, Signatures
National Category
Probability Theory and Statistics
Identifiers
urn:nbn:se:kth:diva-363102 (URN)10.1016/j.sysconle.2025.106100 (DOI)001477537500001 ()2-s2.0-105002841930 (Scopus ID)
Note

QC 20250619

Available from: 2025-05-06 Created: 2025-05-06 Last updated: 2025-06-19Bibliographically approved
Agram, N., Arharas, I., Pucci, G. & Rems, J. (2025). Deep Learning for Energy Market Contracts: Dynkin Game with Doubly RBSDEs.
Open this publication in new window or tab >>Deep Learning for Energy Market Contracts: Dynkin Game with Doubly RBSDEs
2025 (English)Manuscript (preprint) (Other academic)
Abstract [en]

We formulate a Contract for Difference (CfD) with early exit options as a two-player zero-sum Dynkin game, reflecting the strategic interaction between an electricity producer and a regulatory entity. The game incorporates penalties for early termination and mean-reverting price dynamics, with the value characterized through a doubly reflected backward stochastic differential equation (DRBSDE). To compute the contract value and optimal stopping strategies, we develop a neural solver that approximates the DRBSDE solution using a sequence of neural networks trained on simulated trajectories. The method avoids discretizing the state space, supports time-dependent barriers, and scales to highdimensional settings. We establish a convergence result and test the method on two scenarios: a benchmark symmetric game in 20 dimensions, and a CfD model with 24-dimensional electricity prices representing multiple European zones. The results demonstrate that the proposed solver accurately captures the contract’s value and optimal stopping regions, with consistent performance across dimensional settings.

Keywords
Deep learning, Doubly reflected BSDEs, Contract for difference, Dynkin game
National Category
Computational Mathematics
Identifiers
urn:nbn:se:kth:diva-366383 (URN)10.48550/arXiv.2503.00880 (DOI)
Note

QC 20260604

Available from: 2025-07-07 Created: 2025-07-07 Last updated: 2026-06-04Bibliographically approved
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Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0003-1662-0215

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