Andrea Toscani - Academia.edu (original) (raw)

Papers by Andrea Toscani

IEEE Transactions on Instrumentation and Measurement

Nucleation and Atmospheric Aerosols, 2018

This paper presents an assessment of different control strategies to be applied in central receiv... more This paper presents an assessment of different control strategies to be applied in central receiver systems operating with molten salts. The objective is to identify the best control scheme to achieve a threefold objective: (i) to ensure that the outlet temperature of the receiver remains at the highest possible value, (ii) to guarantee that the temperature limit of the working fluid is not exceeded, and (iii) to minimize the temperature gradients induced in the pipes. The analysis is performed in a reference plant whose main specifications are taken from Gemasolar, located in Fuentes de Andalucía (Seville, Spain). The model of the solar receiver and the configuration of the clouds have been presented in previous works by the authors. This work moves one step forward, focusing on the thermal performance of the receiver under different flow management strategies. Two classical control schemes are adopted in this work: feed-forward and feedback. The latter, improved with a variable under-relaxation factor K, is found to be the best choice in order to guarantee safe operation. It yields a lower maximum temperature gradient than the feed-forward scheme and it also ensures that the outlet temperature is always within the limits that avoid degradation of the working fluid (600ºC). Regarding the worst cloud scenario, Total Shadow results to be the most demanding case requiring complete shutdown of the pumping station, at which point the power plant operates on the storage system only.

Microelectronics Reliability, Dec 1, 2020

Methods: Immunohistochemistry (IHC) was performed on tissue samples of untreated (n¼40) and chemo... more Methods: Immunohistochemistry (IHC) was performed on tissue samples of untreated (n¼40) and chemotherapypretreated (n¼14) MPM patients. Different subsets if immune cells were identified based on staining for CD4, CD8, FoxP3, CD68, CD45RO and granzyme B. The expression of the immune checkpoints TIM-3, LAG-3, PD-1 and its ligand PD-L1 was also investigated. The relationship between the immunological parameters and survival, as well as response to chemotherapy was analyzed using the R statistical software. Results: All patients had CD8+ tumor infiltrating lymphocytes (TILs), CD68+ histiocytes and macrophages and CD45RO+ T cells in their stroma, with CD8+ TILs being the predominant cell type of the immune infiltrate. Stromal CD4+ TILs were found in 75% of the untreated and 71% of the pretreated samples. A subset of those cells was also FoxP3+ and these CD4+FoxP3+ cells were positively correlated with stromal CD4 expression (p<0.001). Less than half of the samples showed positivity for granzyme B. Both, untreated and pretreated patients had PD-1+ TILs, while only 10% of the untreated patients also had PD-1+ tumor cells. PD-L1 positivity on lymphocytes and/or tumor cells was observed for more than half of the patients, with significant differences according to the histological subtype (p<0.001). Patients with a sarcomatoid histology showed the most PD-1 expression. TIM-3 was expressed in tumor cells, stromal lymphocytes and plasma cells, less often in pretreated samples compared to untreated samples. All samples were negative for LAG-3. After multivariate analysis stromal CD45RO expression was found to be an independent negative predictive factor for response to chemotherapy (p¼0.017) and expression of CD4 and TIM-3 in lymphoid aggregates were good prognostic factors (p¼0.008; p¼0.001). Conclusion: Our data reveal the diversity of immune cells present in MPM and point to TIM-3 as a new target in mesothelioma. Administering chemotherapy before or together with PD-1/PD-L1/TIM-3 blocking agents may not be the best combination sequence and further research on the predictive value of CD45RO in the stroma might guide patient selection for chemotherapy.

Microelectronics Reliability, Nov 1, 2020

In this work we propose a procedure based on finite element simulations to compute a lumped-param... more In this work we propose a procedure based on finite element simulations to compute a lumped-parameter thermal model of capacitors. The extracted Foster or Cauer network coupled to the electrical model can be useful to evaluate the temperature of capacitors in circuit simulators as SPICE or Simulink. In this way, it is possible to evaluate the expected maximum operative temperature of the capacitor embedded in a circuit before its real application, avoiding unexpected failures since the prototyping stage. Here, we describe the workflow of the method and, finally, the proposed approach will be used for designing snubber capacitors for medium power (60 kW) high frequency AC/AC converter.

IEEE Transactions on Industrial Electronics

IEEE Transactions on Consumer Electronics

Microphone arrays of various sizes and shapes are currently employed in consumer electronics devi... more Microphone arrays of various sizes and shapes are currently employed in consumer electronics devices such as speakerphones, smart TVs, smartphones, and headphones. In this paper, a full-digital, planar microphone array is presented. It makes use of digital Micro Electro-Mechanical Systems (MEMS) microphones, connected through the Automotive Audio Bus (A 2 B). A clock propagation model for A 2 B networks, developed in a previous work, was employed to estimate the effects of jitter and delay on microphone arrays. It will be shown that A 2 B allows for a robust data transmission, while ensuring deterministic latency and channels synchronization, thus overcoming the signal integrity issues which usually affect MEMS capsules. The microphone positioning is also discussed since it greatly affects the spatial accuracy of beamforming. Numerical simulations were performed on four regular geometries to identify the optimal layout in terms of number of capsules and beamforming directivity. An A 2 B planar array with equilateral triangle geometry and four microphones, three in the vertices and one in the center, was built. Experimental measurements were performed, obtaining an excellent matching with numerical simulations. Finally, the concept of an array of arrays (meta-array) is presented, designed by combining several triangular units and analyzed through numerical simulations. Index Terms-Automotive Audio Bus (A 2 B), automotive applications, beamforming, consumer products, digital MEMS microphones, meta-arrays, microphone arrays, planar arrays, spatial audio, triangular arrays. I. INTRODUCTION M ICROPHONE arrays are employed in consumer electronic devices for several applications, such as teleconferencing, speakerphone units, smartphones, and smart TVs. They are mainly used for dereverberation or echo reduction [1]-[4] and speech recognition [5]. Other consumer electronics applications may include Active Noise Control (ANC) [6], [7], multi-channel audio recording [8] and beamforming [9]. When designing such multichannel systems, the type of capsules and data

IEEE Access, 2021

Advanced automotive applications like Active Noise Cancellation (ANC) and Individual Listening Zo... more Advanced automotive applications like Active Noise Cancellation (ANC) and Individual Listening Zones (ILZ) require a high number of transducers (i.e., microphones, accelerometers, and loudspeakers) usually arranged as arrays. Transducer arrays are widely employed in several applications besides automotive field, such as teleconferencing systems, industrial and civil monitoring of noise and vibrations. Automotive Audio Bus (A 2 B) is an audio transport protocol that solves the latest requirements of automotive and industrial fields. A 2 B allows transporting up to 32 channels in a multi-node daisy chain network and guarantees synchronization and low deterministic latency. This paper aims to develop a clock propagation model of an A 2 B network composed by transducer arrays. This model will be useful to evaluate the impact of the bus on the array performance. Firstly, a theoretical description of the A 2 B protocol and jitter analysis is provided. It follows a description of the jitter measures carried out on the clocks distributed along the A 2 B network. Lastly, latency introduced by nodes of the network is investigated.

Advanced Materials and Information Technology Processing, 2014

To improve reliability some systems adopt double redundancy; however, some failure conditions may... more To improve reliability some systems adopt double redundancy; however, some failure conditions may prevent the normal operation of the machine or the machine to reach a safe state. The method proposed in this paper allows the normal operation of the system even in a fault condition of the control unit. The signals resulting from the parallel execution of code are modulated to a higher frequency and decoupled from each control stage using two capacitors; the information is then demodulated to obtain the control signal, either in the case of one or two branches working in the control unit. \uc2\ua9 2014 WIT Press

IEEE Transactions on Consumer Electronics

Frontiers in Energy Research, Dec 14, 2022

The increased use of DC renewable energy resources and DC storage systems, combined with the nece... more The increased use of DC renewable energy resources and DC storage systems, combined with the necessary reduction of energy waste, is boosting the development of DC smart grids. In this scenario, DC load emulation is of great importance. From the hardware point of view, DC buses stability of smart grids and the different DC/DC converter topologies must be tested. From the software point of view, smart grid strategies and job schedulers must be tested with different power absorption profiles. Moreover, DC load emulation can be useful for many other purposes, such as battery characterization, power supply testing, photovoltaic I-V curve measurements, etc. In this work, a cost-efficient DC Active Load (AL) solution is proposed. The principle of the circuit topology is a buck-boostderived converter. This solution can be designed and tested considering the required voltage, current, and maximum input power. Both simulation and experimental results are shown on a 400 W size prototype. Thermal and electrical results validate the simulation model and the AL feasibility.

2022 Second International Conference on Sustainable Mobility Applications, Renewables and Technology (SMART)

Sustainability

Environmental issues and the global need to extend sustainable access to electricity have fostere... more Environmental issues and the global need to extend sustainable access to electricity have fostered a huge amount of research in distributed generation by renewables. The challenges posed by the widespread deployment of distributed generation by renewables, such as intermittent power generation, low inertia, the need for energy storage, etc., call for the development of smart grids serving specific local areas or buildings, referred to as microgrids and nanogrids, respectively. This has led in the last decades to the proposal and actual implementation of a wide variety of system architectures and solutions, and along with that the issue of the power converters needed for interfacing the AC grid with DC micro- or nanogrids, and for DC regulation within the latter. This work offers an overview of the state of the art of research and application of nanogrid architectures, control strategies, and power converter topologies.

2022 IEEE International Workshop on Metrology for Automotive (MetroAutomotive)

2018 20th European Conference on Power Electronics and Applications (EPE'18 ECCE Europe), 2018

This work proposes an architecture of a DC nanogrid with a small PV plant, a battery as storage u... more This work proposes an architecture of a DC nanogrid with a small PV plant, a battery as storage unit, and a three-port converter for low voltage distribution and the management of the electric energy flows. The main objective is to investigate the development of this converter using GaN power FETs. Here are presented the results of preliminary tests carried out using two different GaN FETs in the full bridges needed for the three-port converter. The aim is to identify the best components, among the ones commercially available, for efficiency and thermal design.

Riscaldatore ohmico per il riscaldamento di un prodotto alimentare comprendente: - un inverter (3... more Riscaldatore ohmico per il riscaldamento di un prodotto alimentare comprendente: - un inverter (3) comprendente interruttori (30) controllati; - una coppia (4) di elettrodi posizionabili a contatto con il prodotto alimentare da riscaldare, detto inverter (3) essendo operativamente interposto tra un raddrizzatore (2) della tensione di alimentazione e la coppia (4) di elettrodi; - un trasformatore (6) posto tra l'inverter (3) e la coppia (4) di elettrodi per regolare l'ampiezza della tensione; - mezzi (7) di determinazione della componente continua della corrente in una zona a valle dell'inverter (3) e a monte o in corrispondenza del trasformatore (6); - un sistema (800) di regolazione della durata di chiusura degli interruttori (30) di detto inverter (3) che opera in funzione dei mezzi (7) di determinazione della componente continua minimizzando/annullando detta componente continua

IEEE Transactions on Industrial Electronics, 2013

IEEE Transactions on Industrial Electronics, 2007

This paper describes the realization of a highperformance drive based on stepping motors, with a ... more This paper describes the realization of a highperformance drive based on stepping motors, with a specific reference to the optimal choice of pulsewidth modulation. An original modulation technique is proposed that allows, in conjunction with current feedback, to achieve high performances together with a reduced current ripple. A prototype digital signal processor-based drive was realized for a small-size stepping motor.

IEEE Transactions on Instrumentation and Measurement

Nucleation and Atmospheric Aerosols, 2018

This paper presents an assessment of different control strategies to be applied in central receiv... more This paper presents an assessment of different control strategies to be applied in central receiver systems operating with molten salts. The objective is to identify the best control scheme to achieve a threefold objective: (i) to ensure that the outlet temperature of the receiver remains at the highest possible value, (ii) to guarantee that the temperature limit of the working fluid is not exceeded, and (iii) to minimize the temperature gradients induced in the pipes. The analysis is performed in a reference plant whose main specifications are taken from Gemasolar, located in Fuentes de Andalucía (Seville, Spain). The model of the solar receiver and the configuration of the clouds have been presented in previous works by the authors. This work moves one step forward, focusing on the thermal performance of the receiver under different flow management strategies. Two classical control schemes are adopted in this work: feed-forward and feedback. The latter, improved with a variable under-relaxation factor K, is found to be the best choice in order to guarantee safe operation. It yields a lower maximum temperature gradient than the feed-forward scheme and it also ensures that the outlet temperature is always within the limits that avoid degradation of the working fluid (600ºC). Regarding the worst cloud scenario, Total Shadow results to be the most demanding case requiring complete shutdown of the pumping station, at which point the power plant operates on the storage system only.

Microelectronics Reliability, Dec 1, 2020

Methods: Immunohistochemistry (IHC) was performed on tissue samples of untreated (n¼40) and chemo... more Methods: Immunohistochemistry (IHC) was performed on tissue samples of untreated (n¼40) and chemotherapypretreated (n¼14) MPM patients. Different subsets if immune cells were identified based on staining for CD4, CD8, FoxP3, CD68, CD45RO and granzyme B. The expression of the immune checkpoints TIM-3, LAG-3, PD-1 and its ligand PD-L1 was also investigated. The relationship between the immunological parameters and survival, as well as response to chemotherapy was analyzed using the R statistical software. Results: All patients had CD8+ tumor infiltrating lymphocytes (TILs), CD68+ histiocytes and macrophages and CD45RO+ T cells in their stroma, with CD8+ TILs being the predominant cell type of the immune infiltrate. Stromal CD4+ TILs were found in 75% of the untreated and 71% of the pretreated samples. A subset of those cells was also FoxP3+ and these CD4+FoxP3+ cells were positively correlated with stromal CD4 expression (p<0.001). Less than half of the samples showed positivity for granzyme B. Both, untreated and pretreated patients had PD-1+ TILs, while only 10% of the untreated patients also had PD-1+ tumor cells. PD-L1 positivity on lymphocytes and/or tumor cells was observed for more than half of the patients, with significant differences according to the histological subtype (p<0.001). Patients with a sarcomatoid histology showed the most PD-1 expression. TIM-3 was expressed in tumor cells, stromal lymphocytes and plasma cells, less often in pretreated samples compared to untreated samples. All samples were negative for LAG-3. After multivariate analysis stromal CD45RO expression was found to be an independent negative predictive factor for response to chemotherapy (p¼0.017) and expression of CD4 and TIM-3 in lymphoid aggregates were good prognostic factors (p¼0.008; p¼0.001). Conclusion: Our data reveal the diversity of immune cells present in MPM and point to TIM-3 as a new target in mesothelioma. Administering chemotherapy before or together with PD-1/PD-L1/TIM-3 blocking agents may not be the best combination sequence and further research on the predictive value of CD45RO in the stroma might guide patient selection for chemotherapy.

Microelectronics Reliability, Nov 1, 2020

In this work we propose a procedure based on finite element simulations to compute a lumped-param... more In this work we propose a procedure based on finite element simulations to compute a lumped-parameter thermal model of capacitors. The extracted Foster or Cauer network coupled to the electrical model can be useful to evaluate the temperature of capacitors in circuit simulators as SPICE or Simulink. In this way, it is possible to evaluate the expected maximum operative temperature of the capacitor embedded in a circuit before its real application, avoiding unexpected failures since the prototyping stage. Here, we describe the workflow of the method and, finally, the proposed approach will be used for designing snubber capacitors for medium power (60 kW) high frequency AC/AC converter.

IEEE Transactions on Industrial Electronics

IEEE Transactions on Consumer Electronics

Microphone arrays of various sizes and shapes are currently employed in consumer electronics devi... more Microphone arrays of various sizes and shapes are currently employed in consumer electronics devices such as speakerphones, smart TVs, smartphones, and headphones. In this paper, a full-digital, planar microphone array is presented. It makes use of digital Micro Electro-Mechanical Systems (MEMS) microphones, connected through the Automotive Audio Bus (A 2 B). A clock propagation model for A 2 B networks, developed in a previous work, was employed to estimate the effects of jitter and delay on microphone arrays. It will be shown that A 2 B allows for a robust data transmission, while ensuring deterministic latency and channels synchronization, thus overcoming the signal integrity issues which usually affect MEMS capsules. The microphone positioning is also discussed since it greatly affects the spatial accuracy of beamforming. Numerical simulations were performed on four regular geometries to identify the optimal layout in terms of number of capsules and beamforming directivity. An A 2 B planar array with equilateral triangle geometry and four microphones, three in the vertices and one in the center, was built. Experimental measurements were performed, obtaining an excellent matching with numerical simulations. Finally, the concept of an array of arrays (meta-array) is presented, designed by combining several triangular units and analyzed through numerical simulations. Index Terms-Automotive Audio Bus (A 2 B), automotive applications, beamforming, consumer products, digital MEMS microphones, meta-arrays, microphone arrays, planar arrays, spatial audio, triangular arrays. I. INTRODUCTION M ICROPHONE arrays are employed in consumer electronic devices for several applications, such as teleconferencing, speakerphone units, smartphones, and smart TVs. They are mainly used for dereverberation or echo reduction [1]-[4] and speech recognition [5]. Other consumer electronics applications may include Active Noise Control (ANC) [6], [7], multi-channel audio recording [8] and beamforming [9]. When designing such multichannel systems, the type of capsules and data

IEEE Access, 2021

Advanced automotive applications like Active Noise Cancellation (ANC) and Individual Listening Zo... more Advanced automotive applications like Active Noise Cancellation (ANC) and Individual Listening Zones (ILZ) require a high number of transducers (i.e., microphones, accelerometers, and loudspeakers) usually arranged as arrays. Transducer arrays are widely employed in several applications besides automotive field, such as teleconferencing systems, industrial and civil monitoring of noise and vibrations. Automotive Audio Bus (A 2 B) is an audio transport protocol that solves the latest requirements of automotive and industrial fields. A 2 B allows transporting up to 32 channels in a multi-node daisy chain network and guarantees synchronization and low deterministic latency. This paper aims to develop a clock propagation model of an A 2 B network composed by transducer arrays. This model will be useful to evaluate the impact of the bus on the array performance. Firstly, a theoretical description of the A 2 B protocol and jitter analysis is provided. It follows a description of the jitter measures carried out on the clocks distributed along the A 2 B network. Lastly, latency introduced by nodes of the network is investigated.

Advanced Materials and Information Technology Processing, 2014

To improve reliability some systems adopt double redundancy; however, some failure conditions may... more To improve reliability some systems adopt double redundancy; however, some failure conditions may prevent the normal operation of the machine or the machine to reach a safe state. The method proposed in this paper allows the normal operation of the system even in a fault condition of the control unit. The signals resulting from the parallel execution of code are modulated to a higher frequency and decoupled from each control stage using two capacitors; the information is then demodulated to obtain the control signal, either in the case of one or two branches working in the control unit. \uc2\ua9 2014 WIT Press

IEEE Transactions on Consumer Electronics

Frontiers in Energy Research, Dec 14, 2022

The increased use of DC renewable energy resources and DC storage systems, combined with the nece... more The increased use of DC renewable energy resources and DC storage systems, combined with the necessary reduction of energy waste, is boosting the development of DC smart grids. In this scenario, DC load emulation is of great importance. From the hardware point of view, DC buses stability of smart grids and the different DC/DC converter topologies must be tested. From the software point of view, smart grid strategies and job schedulers must be tested with different power absorption profiles. Moreover, DC load emulation can be useful for many other purposes, such as battery characterization, power supply testing, photovoltaic I-V curve measurements, etc. In this work, a cost-efficient DC Active Load (AL) solution is proposed. The principle of the circuit topology is a buck-boostderived converter. This solution can be designed and tested considering the required voltage, current, and maximum input power. Both simulation and experimental results are shown on a 400 W size prototype. Thermal and electrical results validate the simulation model and the AL feasibility.

2022 Second International Conference on Sustainable Mobility Applications, Renewables and Technology (SMART)

Sustainability

Environmental issues and the global need to extend sustainable access to electricity have fostere... more Environmental issues and the global need to extend sustainable access to electricity have fostered a huge amount of research in distributed generation by renewables. The challenges posed by the widespread deployment of distributed generation by renewables, such as intermittent power generation, low inertia, the need for energy storage, etc., call for the development of smart grids serving specific local areas or buildings, referred to as microgrids and nanogrids, respectively. This has led in the last decades to the proposal and actual implementation of a wide variety of system architectures and solutions, and along with that the issue of the power converters needed for interfacing the AC grid with DC micro- or nanogrids, and for DC regulation within the latter. This work offers an overview of the state of the art of research and application of nanogrid architectures, control strategies, and power converter topologies.

2022 IEEE International Workshop on Metrology for Automotive (MetroAutomotive)

2018 20th European Conference on Power Electronics and Applications (EPE'18 ECCE Europe), 2018

This work proposes an architecture of a DC nanogrid with a small PV plant, a battery as storage u... more This work proposes an architecture of a DC nanogrid with a small PV plant, a battery as storage unit, and a three-port converter for low voltage distribution and the management of the electric energy flows. The main objective is to investigate the development of this converter using GaN power FETs. Here are presented the results of preliminary tests carried out using two different GaN FETs in the full bridges needed for the three-port converter. The aim is to identify the best components, among the ones commercially available, for efficiency and thermal design.

Riscaldatore ohmico per il riscaldamento di un prodotto alimentare comprendente: - un inverter (3... more Riscaldatore ohmico per il riscaldamento di un prodotto alimentare comprendente: - un inverter (3) comprendente interruttori (30) controllati; - una coppia (4) di elettrodi posizionabili a contatto con il prodotto alimentare da riscaldare, detto inverter (3) essendo operativamente interposto tra un raddrizzatore (2) della tensione di alimentazione e la coppia (4) di elettrodi; - un trasformatore (6) posto tra l'inverter (3) e la coppia (4) di elettrodi per regolare l'ampiezza della tensione; - mezzi (7) di determinazione della componente continua della corrente in una zona a valle dell'inverter (3) e a monte o in corrispondenza del trasformatore (6); - un sistema (800) di regolazione della durata di chiusura degli interruttori (30) di detto inverter (3) che opera in funzione dei mezzi (7) di determinazione della componente continua minimizzando/annullando detta componente continua

IEEE Transactions on Industrial Electronics, 2013

IEEE Transactions on Industrial Electronics, 2007

This paper describes the realization of a highperformance drive based on stepping motors, with a ... more This paper describes the realization of a highperformance drive based on stepping motors, with a specific reference to the optimal choice of pulsewidth modulation. An original modulation technique is proposed that allows, in conjunction with current feedback, to achieve high performances together with a reduced current ripple. A prototype digital signal processor-based drive was realized for a small-size stepping motor.