Carlos Valderrama

Dr. Carlos Valderrama

Electronics and Microelectronics, Polytechnic Faculty, University of Mons, 7000 Mons, Belgium
orcid
Professor PhD Head of Department Electronics & Microelectron...

Research Focus & Metrics

Academic Career Length

17Years (2010-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
16 September 2021 in Electronics
Verified
Journal Article
Open access
PDF file
SBSafa Bouguezzi
Safa Bouguezzi
HFHana Ben Fredj
Hana Ben Fredj
Tarek BelabedTarek Belabed
Tarek Belabed
Carlos ValderramaCarlos Valderrama
Carlos Valderrama
Hassene FaiedhHassene Faiedh
Hassene Faiedh
Chokri SouaniChokri Souani
Chokri Souani
Convolutional Neural Networks (CNN) continue to dominate research in the area of hardware acceleration using Field Programmable Gate Arrays (FPGA), proving its effectiveness in a variety of computer vision applications such as object segmentation, image classification, face detection, and traffic signs recognition, among others. However, there are numerous constraints for deploying CNNs on FPGA, including limited on-chip memory, CNN size, and configuration parameters. This paper introduces Ad-MobileNet, an advanced CNN model inspired by the baseline MobileNet model. The proposed model uses an Ad-depth engine, which is an improved version of the depth-wise separable convolution unit. Moreover, we propose an FPGA-based implementation model that supports the Mish, TanhExp, and ReLU activation functions. The experimental results using the CIFAR-10 dataset show that our Ad-MobileNet has a classification accuracy of 88.76% while requiring little computational hardware resources. Compared to state-of-the-art methods, our proposed method has a fairly high recognition rate while using fewer computational hardware resources. Indeed, the proposed model helps to reduce hardware resources by more than 41% compared to that of the baseline model.

17 June 2021 in IEEE Access
Verified
Journal Article
Open access
Tarek BelabedTarek Belabed
Tarek Belabed
MCMaria Gracielly Coutinho
Maria Gracielly Coutinho
Marcelo A. C. FernandesMarcelo A. C. Fernandes
Marcelo A. C. Fernandes
Carlos ValderramaCarlos Valderrama
Carlos Valderrama
Chokri SouaniChokri Souani
Chokri Souani
Deep Learning techniques have been successfully applied to solve many Artificial Intelligence (AI) applications problems. However, owing to topologies with many hidden layers, Deep Neural Networks (DNNs) have high computational complexity, which makes their deployment difficult in contexts highly constrained by requirements such as performance, real-time processing, or energy efficiency. Numerous hardware/software optimization techniques using GPUs, ASICs, and reconfigurable computing (i.e, FPGAs), have been proposed in the literature. With FPGAs, very specialized architectures have been developed to provide an optimal balance between high-speed and low power. However, when targeting edge computing, user requirements and hardware constraints must be efficiently met. Therefore, in this work, we only focus on reconfigurable embedded systems based on the Xilinx ZYNQ SoC and popular DNNs that can be implemented on Embedded Edge improving performance per watt while maintaining accuracy. In this context, we propose an automated framework for the implementation of hardware-accelerated DNN architectures. This framework provides an end-to-end solution that facilitates the efficient deployment of topologies on FPGAs by combining custom hardware scalability with optimization strategies. Cutting-edge comparisons and experimental results demonstrate that the architectures developed by our framework offer the best compromise between performance, energy consumption, and system costs. For instance, the low power (0.266W) DNN topologies generated for the MNIST database achieved a high throughput of 3,626 FPS.

25 May 2022 in Neural Processing Letters
Verified
Journal Article
Closed access
PDF file
AAAfef Abidi
Afef Abidi
Khaled Ben KhalifaKhaled Ben Khalifa
Khaled Ben Khalifa
RCRidha Ben Cheikh
Ridha Ben Cheikh
Carlos ValderramaCarlos Valderrama
Carlos Valderrama
MBMohamed Hedi Bedoui
Mohamed Hedi Bedoui

29 February 2020 in Electronics
Verified
Journal Article
Open access
PDF file
CYCamille Yvanoff-Frenchin
Camille Yvanoff-Frenchin
VRVitor Ramos
Vitor Ramos
Tarek BelabedTarek Belabed
Tarek Belabed
Carlos ValderramaCarlos Valderrama
Carlos Valderrama
We need open platforms driven by specialists, in which queries can be created and collected for long periods and the diagnosis made based on a rigorous clinical follow-up. In this work, we developed a multi-language robot interface helping to evaluate the mental health of seniors by interacting through questions. Through the voice interface, the specialist can propose questions, as well as receive users’ answers, in text form. The robot can automatically interact with the user using the appropriate language. It can process the answers and under the guidance of a specialist, questions and answers can be oriented towards the desired therapy direction. The prototype was implemented on an embedded device meant for edge computing, thus it was able to filter environmental noise and can be placed anywhere at home. The proposed platform allows the integration of well-known open source and commercial data flow processing frameworks. The experience is now available for specialists to create queries and answers through a Web-based interface.

2 April 2020 in Sensors
Verified
Journal Article
Open access
PDF file
SSSérgio Natan Silva
Sérgio Natan Silva
FLFelipe Fernandes Lopes
Felipe Fernandes Lopes
Carlos ValderramaCarlos Valderrama
Carlos Valderrama
Marcelo A. C. FernandesMarcelo A. C. Fernandes
Marcelo A. C. Fernandes
This work proposes dedicated hardware for an intelligent control system on Field Programmable Gate Array (FPGA). The intelligent system is represented as Takagi–Sugeno Fuzzy-PI controller. The implementation uses a fully parallel strategy associated with a hybrid bit format scheme (fixed-point and floating-point). Two hardware designs are proposed; the first one uses a single clock cycle processing architecture, and the other uses a pipeline scheme. The bit accuracy was tested by simulation with a nonlinear control system of a robotic manipulator. The area, throughput, and dynamic power consumption of the implemented hardware are used to validate and compare the results of this proposal. The results achieved allow the use of the proposed hardware in applications with high-throughput, low-power and ultra-low-latency requirements such as teleoperation of robot manipulators, tactile internet, or industry 4.0 automation, among others.

23 February 2022 in Electronics
Verified
Journal Article
Open access
PDF file
Vitor Ramos Gomes da SilvaVitor Ramos Gomes da Silva
Vitor Ramos Gomes da Silva
ASAnderson Bráulio Nóbrega da Silva
Anderson Bráulio Nóbrega da Silva
Carlos ValderramaCarlos Valderrama
Carlos Valderrama
PMPierre Manneback
Pierre Manneback
Samuel Xavier-de-SouzaSamuel Xavier-de-Souza
Samuel Xavier-de-Souza
High-performance computing systems have become increasingly dynamic, complex, and unpredictable. To help build software that uses full-system capabilities, performance measurement and analysis tools exploit extensive execution analysis focusing on single-run results. Despite being effective in identifying performance hotspots and bottlenecks, these tools are not sufficiently suitable to evaluate the overall scalability trends of parallel applications. Either they lack the support for combining data from multiple runs or collect excessive data, causing unnecessary overhead. In this work, we present a tool for automatically measuring and comparing several executions of a parallel application according to various scenarios characterized by the input arrangements, the number of threads, number of cores, and frequencies. Unlike other existing performance analysis tools, the proposed work covers some gaps in specialized features necessary to better understand computational resources scalability trends across configurations. In order to improve scalability analysis and productivity over the vast spectrum of possible configurations, the proposed tool features automatic instrumentation, direct mapping of parallel regions, accuracy-preserving data reductions, and ease of use. As it aims at accurately understanding scalability trends of parallel applications, detailed single-run performance analyses show minimal intrusion (less than 1% overhead).