Maria Liz Crespo

Dr. Maria Liz Crespo

International Centre for Theoretical Physics (ICTP), Trieste, Italy
orcid

Research Focus & Metrics

Academic Career Length

32Years (1995-Present)

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

Representative Publications

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21 August 2019 in Sensors
Verified
Journal Article
Open access
PDF file
SASani Abba
Sani Abba
WJWadumi Jonah
Wadumi Jonah
JLJeong-A Lee
Jeong-A Lee
Maria Liz CrespoMaria Liz Crespo
Maria Liz Crespo
Irrigation systems are becoming increasingly important, owing to the increase in human population, global warming, and food demand. This study aims to design a low-cost autonomous sensor interface to automate the monitoring and control of irrigation systems in remote locations, and to optimize water use for irrigation farming. An internet of things-based irrigation monitoring and control system, employing sensors and actuators, is designed to facilitate the autonomous supply of adequate water from a reservoir to domestic crops in a smart irrigation systems. System development lifecycle and waterfall model design methodologies have been employed in the development paradigm. The Proteus 8.5 design suite, Arduino integrated design environment, and embedded C programming language are commonly used to develop and implement a real working prototype. A pumping mechanism has been used to supply the water required by the soil. The prototype provides power supply, sensing, monitoring and control, and internet connectivity capabilities. Experimental and simulation results demonstrate the flexibility and practical applicability of the proposed system, and are of paramount importance, not only to farmers, but also for the expansion of economic activity. Furthermore, this system reduces the high level of supervision required to supply irrigation water, enabling remote monitoring and control.

20 July 2024 in Heliyon
Verified
Journal Article
Open access
SASani Abba
Sani Abba
ABAli Mohammed Bizi
Ali Mohammed Bizi
JLJeong-A Lee
Jeong-A Lee
SBSouley Bakouri
Souley Bakouri
Maria Liz CrespoMaria Liz Crespo
Maria Liz Crespo
The concept of security is becoming a global challenge, and governments, stakeholders, corporate societies, and individuals must urgently create a reasonable protection mechanism for good. Therefore, a real-time surveillance system is essential for detection, tracking, and monitoring. Many studies have attempted to provide better solutions but more research and better approaches are essential. This study presents a real-time framework for object detection and tracking for security surveillance systems. The system has been designed based on approximate median filtering, component labeling, background subtraction, and deep learning approaches. The new algorithms for object detection, tracking, and recognition have been implemented using Python and integrated with C# programming languages for ease of use. A software application framework is designed, implemented, and evaluated. The experimental results based on MOT-Challenge performance metrics show that the proposed algorithms have much better performance in terms of accuracy and precision on the MOT15, MOT16, and MOT17 datasets compared to state-of-the-art approaches. This framework also provides an accurate and effective means of monitoring and recognizing moving objects. The software development, including the design of the framework user interfaces, is coded in the C# programming language and integrated with Python using Microsoft Visual Studio (2019 edition). The integration is performed to provide a convenient user interface and to enable the execution of the framework as a standard and standalone software application. Future studies will consider the dynamic scalability of the framework to accommodate different surveillance application areas in overcrowded scenarios. Multiple data sources are integrated to enhance the performance for different scene times, locations, and weather conditions. Furthermore, other object-detection techniques such as You Only Look Once (YOLO) and its variants shall be considered in future studies. These techniques allow the framework to adapt to complex situations in which security surveillance is challenging.

23 August 2022 in IEEE Access
Verified
Journal Article
Open access
RMRomina Soledad Molina
Romina Soledad Molina
Veronica Gil-CostaVeronica Gil-Costa
Veronica Gil-Costa
Maria Liz CrespoMaria Liz Crespo
Maria Liz Crespo
GRGiovanni (Gianni) Ramponi
Giovanni (Gianni) Ramponi
Hardware accelerators based on field programmable gate array (FPGA) and system on chip (SoC) devices have gained attention in recent years. One of the main reasons is that these devices contain reconfigurable logic, which makes them feasible for boosting the performance of applications. High-level synthesis (HLS) tools facilitate the creation of FPGA code from a high level of abstraction using different directives to obtain an optimized hardware design based on performance metrics. However, the complexity of the design space depends on different factors such as the number of directives used in the source code, the available resources in the device, and the clock frequency. Design space exploration (DSE) techniques comprise the evaluation of multiple implementations with different combinations of directives to obtain a design with a good compromise between different metrics. This paper presents a survey of models, methodologies, and frameworks proposed for metric estimation, FPGA-based DSE, and power consumption estimation on FPGA/SoC. The main features, limitations, and trade-offs of these approaches are described. We also present the integration of existing models and frameworks in diverse research areas and identify the different challenges to be addressed.

21 June 2023 in IEEE Access
Verified
Journal Article
Open access
WSWerner Florian Samayoa
Werner Florian Samayoa
Maria Liz CrespoMaria Liz Crespo
Maria Liz Crespo
ACAndres Cicuttin
Andres Cicuttin
Sergio CarratoSergio Carrato
Sergio Carrato
In recent years, the most powerful supercomputers have already reached megawatt power consumption levels, an important issue that challenges sustainability and shows the impossibility of maintaining this trend. To this date, the prevalent approach to super-computing is dominated by CPUs and GPUs. Given their fixed architectures with generic instruction sets, they have been favored with lots of tools and mature workflows which led to mass adoption and further growth. However, reconfigurable hardware such as FPGAs has repeatedly proven that it offers substantial advantages over this super-computing approach concerning performance and power consumption. In this survey, we review the most relevant works that advanced the field of heterogeneous super-computing using FPGAs focusing on their architectural characteristics. Each work was divided into three main parts: network, hardware, and software tools. All implementations face challenges that involve all three parts. These dependencies result in compromises that designers must take into account. The advantages and limitations of each approach are discussed and compared in detail. The classification and study of the architectures illustrate the trade-offs of the solutions and help identify open problems and research lines.

20 March 2017 in X-Ray Spectrometry
Verified
Journal Article
Closed access
PDF file
JBJernej Bufon
Jernej Bufon
AGAlessandra Gianoncelli
Alessandra Gianoncelli
MAMahdi Ahangarianabhari
Mahdi Ahangarianabhari
MAMatteo Altissimo
Matteo Altissimo
PBPierluigi Bellutti
Pierluigi Bellutti
NZNicola Zorzi
Nicola Zorzi

6 June 2023 in IEEE Transactions on Instrumentation and Measurement
Verified
Journal Article
Closed access
CNCharn Loong Ng
Charn Loong Ng
Mamun Bin Ibne ReazMamun Bin Ibne Reaz
Mamun Bin Ibne Reaz
Maria Liz CrespoMaria Liz Crespo
Maria Liz Crespo
ACAndres Cicuttin
Andres Cicuttin
MSMohd. Ibrahim Shapiai
Mohd. Ibrahim Shapiai
Muhammad E. H. ChowdhuryMuhammad E. H. Chowdhury
Muhammad E. H. Chowdhury
Musculoskeletal diseases and disorders (MSDs) have a significant negative impact on personal health and the worldwide economy. Leveraging the advancement of wearable sensing technology to provide electromyography (EMG) measurement capability can improve the efficiency of the public healthcare strategy to combat MSDs. Integrating conventional EMG contact electrodes into a wearable device is proven to be a challenge because it requires direct electrical contact with the body and has a dependency on the conductive gel. Existing prototypes of capacitive electromyography (cEMG) sensors are typically large and designed with a hybrid printed circuit board. This research paper presents a fully flexible cEMG biomedical sensor with integrated front-end analog circuitry in only a medical plaster size. An efficient moving average squared (MASq) technique is presented to effectively suppress the noise floor and improve the signal quality. The experimental results of measuring EMG signals from flexor carpi radialis, extensor carpi radialis, and biceps brachii using the flexible cEMG biomedical sensor are presented. The post-process data recorded signal-to-noise ratios ranging from 1.8 – 5.7 while achieving practically 100% sensitivity in measuring muscle contractions. Its miniature, rugged, and flexible characteristics allow it to operate as a standalone adhesive plaster sensor or integrate into wearable applications.