Marcos Quilez | Universitat Politecnica de Catalunya (original) (raw)

Papers by Marcos Quilez

Waste Management, 2014

Monitoring of the moisture and temperature of composting process is a key factor to obtain a qual... more Monitoring of the moisture and temperature of composting process is a key factor to obtain a quality product beyond the quality of raw materials. Current methodologies for monitoring these two parameters are time consuming for workers, sometimes not sufficiently reliable to help decision-making and thus are ignored in some cases. This article describes an advance on monitoring of composting process through a Wireless Sensor Network (WSN) that allows measurement of temperature and moisture in real time in multiple points of the composting material, the Compo-ball system. To implement such measurement capabilities on-line, a WSN composed of multiple sensor nodes was designed and implemented to provide the staff with an efficient monitoring composting management tool. After framing the problem, the objectives and characteristics of the WSN are briefly discussed and a short description of the hardware and software of the network's components are presented. Presentation and discussion of practical issues and results obtained with the WSN during a demonstration stage that took place in several composting sites concludes the paper.

Journal of Accessibility and Design For All, Nov 10, 2012

1999 IEEE International Symposium on Electromagnetic Compatability. Symposium Record (Cat. No.99CH36261), 1999

In some situations, the OATS (open air test site) far field condition cannot be satisfied, and ne... more In some situations, the OATS (open air test site) far field condition cannot be satisfied, and near field measurements must be performed. The EMI environment inside a car is one of these situations, where only near field probes can be used for measurement. We developed a near field probe that can measure the electric and magnetic fields simultaneously. The probe

Becoming autonomous is one of the biggest challenges for many people with disabilities. Increasin... more Becoming autonomous is one of the biggest challenges for many people with disabilities. Increasing their autonomy usually involves the use of both a wheelchair and any kind of digital assistant such as a computer or a tablet to communicate, to work or even only for leisure. In such situations, those people are forced to use two different human interfaces, one to move a pointer and the other to drive the wheelchair. A joystick is the most common commercial solution to control a wheelchair whereas there are many different adapted interfaces to emulate the use of a mouse. In this paper we propose the use of a wheelchair joystick as a human interface for electronic devices such as computers, tablets or smartphones. This designed system captures the motion of the joystick on a wheelchair to move the cursor or the pointer of any digital device including an USB port. It avoids any mechanical or electronic change in the joystick to keep its original safety and warranty. This non-invasive mo...

1999 IEEE International Symposium on Electromagnetic Compatability. Symposium Record (Cat. No.99CH36261), 1999

Electromagnetic radiated emissions from an automotive CAN bus are analyzed. This type of subsyste... more Electromagnetic radiated emissions from an automotive CAN bus are analyzed. This type of subsystems can produce interference's on electronic components or submodules, including radio receptors. Measurements inside and outside the car are performed. The control of the differential signal slope results in an easy way to reduce EMI at high frequencies. Finally, a set of near field measurements inside the

10th International Multi-Conferences on Systems, Signals & Devices 2013 (SSD13), 2013

In this contribution we aim at proposing entropy measurements in resistive elements to characteri... more In this contribution we aim at proposing entropy measurements in resistive elements to characterize the induced damage due to current and Joule effect dissipation. 0.25 W off the shelf resistors are biased with constant voltage and pulsed voltage signals, leading to power dissipation in the range of 2 W -5 W, to accelerate resistor failure. Entropy is inferred from injected power with respect to temperature evolution. Results show an entropy increase as a function of time, thus being possible to define threshold entropy prior to resistor failure. Entropy generation rate also shows a sudden increase in strongly damaged resistors.

2008 International Symposium on Electromagnetic Compatibility - EMC Europe, 2008

In this article we present measurements of electric and magnetic fields in industrial environment... more In this article we present measurements of electric and magnetic fields in industrial environments. A frequency selective probe to measure E and H fields simultaneously has been used. The probe, implemented on a printed circuit board, allows us to measure the spatial distribution of the fields.

2007 IEEE Instrumentation & Measurement Technology Conference IMTC 2007, 2007

Dual-slope analog-to-digital converters are attractive because of its good series mode rejection ... more Dual-slope analog-to-digital converters are attractive because of its good series mode rejection ratio (SMRR), which highly attenuates interference coupled to the input signal. However, electromagnetic interference (EMI) can also affect the other ports of the converter, and this has received much less attention. This work is an experimental study on the susceptibility of dual-slope ADCs to EMI coupled to their signal, voltage reference and power supply ports. Perturbation has been directly coupled to the port (or ports) under test, while keeping the other ports interference-free. The results show that the supply port is immune to interference but the voltage reference port is quite susceptible. Further, ratiometric measurements do not cancel out interference simultaneously added to the input and voltage reference ports.

Lecture Notes in Computer Science, 2006

Abstract. Being autonomous is one of the biggest challenges for many people with disabilities. Wh... more Abstract. Being autonomous is one of the biggest challenges for many people with disabilities. While wheelchairs enable individuals to move freely, com-puters allow them to communicate, work, etc. by their own. In many cases both devices are controlled by two ...

Waste Management, 2014

Monitoring of the moisture and temperature of composting process is a key factor to obtain a qual... more Monitoring of the moisture and temperature of composting process is a key factor to obtain a quality product beyond the quality of raw materials. Current methodologies for monitoring these two parameters are time consuming for workers, sometimes not sufficiently reliable to help decision-making and thus are ignored in some cases. This article describes an advance on monitoring of composting process through a Wireless Sensor Network (WSN) that allows measurement of temperature and moisture in real time in multiple points of the composting material, the Compo-ball system. To implement such measurement capabilities on-line, a WSN composed of multiple sensor nodes was designed and implemented to provide the staff with an efficient monitoring composting management tool. After framing the problem, the objectives and characteristics of the WSN are briefly discussed and a short description of the hardware and software of the network's components are presented. Presentation and discussion of practical issues and results obtained with the WSN during a demonstration stage that took place in several composting sites concludes the paper.

IEEE Transactions on Electromagnetic Compatibility, 2000

In this paper, we present a frequency-selective probe intended to measure E and H fields simultan... more In this paper, we present a frequency-selective probe intended to measure E and H fields simultaneously in the near-field region. The probe is implemented on a printed circuit board (PCB) that provides some advantages compared to those presented in previous works. The existing theoretical models are adapted in order to include the effect of both PCB trace and dielectric support. The probe is used for in situ electromagnetic compatibility (EMC) characterization of industrial installations, which offers valuable information that cannot be obtained by the usual EMC measurements.

IEEE Transactions on Biomedical Engineering, 2000

The purpose of this paper is to analyze the influence of the metallic structures of a realistic c... more The purpose of this paper is to analyze the influence of the metallic structures of a realistic car body frame on the specific absorption rate (SAR) produced by a cell phone when a complete human body model is placed at different locations inside the vehicle, and to identify the relevant parameters responsible for these changes. The modeling and analysis of the whole system was conducted by means of computer simulations based on the full wave finite-difference time-domain (FDTD) numerical method. The excitation considered was an 835 MHz 2 dipole located as a handsfree communication device or as a hand-held portable system. We compared the SAR at different planes on the human model, placed inside the vehicle with respect to the free space situation. The presence of the car body frame significantly changes the SAR distributions, especially when the dipole is far from the body. Although the results are not conclusive on this point, this change in SAR distribution is not likely to produce an increase above the limits in current guidelines for partial body exposure, but may be significant for whole-body exposure. The most relevant change found was the change in the impedance of the dipole, affecting the radiated power. A complementary result from the electromagnetic computations performed is the change in the electromagnetic field distribution inside a vehicle when human bodies are present. The whole vehicle model has been optimized to provide accurate results for sources placed inside the vehicle, while keeping low requirements for computer storage and simulation time.

Waste Management, 2014

Monitoring of the moisture and temperature of composting process is a key factor to obtain a qual... more Monitoring of the moisture and temperature of composting process is a key factor to obtain a quality product beyond the quality of raw materials. Current methodologies for monitoring these two parameters are time consuming for workers, sometimes not sufficiently reliable to help decision-making and thus are ignored in some cases. This article describes an advance on monitoring of composting process through a Wireless Sensor Network (WSN) that allows measurement of temperature and moisture in real time in multiple points of the composting material, the Compo-ball system. To implement such measurement capabilities on-line, a WSN composed of multiple sensor nodes was designed and implemented to provide the staff with an efficient monitoring composting management tool. After framing the problem, the objectives and characteristics of the WSN are briefly discussed and a short description of the hardware and software of the network's components are presented. Presentation and discussion of practical issues and results obtained with the WSN during a demonstration stage that took place in several composting sites concludes the paper.

Journal of Accessibility and Design For All, Nov 10, 2012

1999 IEEE International Symposium on Electromagnetic Compatability. Symposium Record (Cat. No.99CH36261), 1999

In some situations, the OATS (open air test site) far field condition cannot be satisfied, and ne... more In some situations, the OATS (open air test site) far field condition cannot be satisfied, and near field measurements must be performed. The EMI environment inside a car is one of these situations, where only near field probes can be used for measurement. We developed a near field probe that can measure the electric and magnetic fields simultaneously. The probe

Becoming autonomous is one of the biggest challenges for many people with disabilities. Increasin... more Becoming autonomous is one of the biggest challenges for many people with disabilities. Increasing their autonomy usually involves the use of both a wheelchair and any kind of digital assistant such as a computer or a tablet to communicate, to work or even only for leisure. In such situations, those people are forced to use two different human interfaces, one to move a pointer and the other to drive the wheelchair. A joystick is the most common commercial solution to control a wheelchair whereas there are many different adapted interfaces to emulate the use of a mouse. In this paper we propose the use of a wheelchair joystick as a human interface for electronic devices such as computers, tablets or smartphones. This designed system captures the motion of the joystick on a wheelchair to move the cursor or the pointer of any digital device including an USB port. It avoids any mechanical or electronic change in the joystick to keep its original safety and warranty. This non-invasive mo...

1999 IEEE International Symposium on Electromagnetic Compatability. Symposium Record (Cat. No.99CH36261), 1999

Electromagnetic radiated emissions from an automotive CAN bus are analyzed. This type of subsyste... more Electromagnetic radiated emissions from an automotive CAN bus are analyzed. This type of subsystems can produce interference's on electronic components or submodules, including radio receptors. Measurements inside and outside the car are performed. The control of the differential signal slope results in an easy way to reduce EMI at high frequencies. Finally, a set of near field measurements inside the

10th International Multi-Conferences on Systems, Signals & Devices 2013 (SSD13), 2013

In this contribution we aim at proposing entropy measurements in resistive elements to characteri... more In this contribution we aim at proposing entropy measurements in resistive elements to characterize the induced damage due to current and Joule effect dissipation. 0.25 W off the shelf resistors are biased with constant voltage and pulsed voltage signals, leading to power dissipation in the range of 2 W -5 W, to accelerate resistor failure. Entropy is inferred from injected power with respect to temperature evolution. Results show an entropy increase as a function of time, thus being possible to define threshold entropy prior to resistor failure. Entropy generation rate also shows a sudden increase in strongly damaged resistors.

2008 International Symposium on Electromagnetic Compatibility - EMC Europe, 2008

In this article we present measurements of electric and magnetic fields in industrial environment... more In this article we present measurements of electric and magnetic fields in industrial environments. A frequency selective probe to measure E and H fields simultaneously has been used. The probe, implemented on a printed circuit board, allows us to measure the spatial distribution of the fields.

2007 IEEE Instrumentation & Measurement Technology Conference IMTC 2007, 2007

Dual-slope analog-to-digital converters are attractive because of its good series mode rejection ... more Dual-slope analog-to-digital converters are attractive because of its good series mode rejection ratio (SMRR), which highly attenuates interference coupled to the input signal. However, electromagnetic interference (EMI) can also affect the other ports of the converter, and this has received much less attention. This work is an experimental study on the susceptibility of dual-slope ADCs to EMI coupled to their signal, voltage reference and power supply ports. Perturbation has been directly coupled to the port (or ports) under test, while keeping the other ports interference-free. The results show that the supply port is immune to interference but the voltage reference port is quite susceptible. Further, ratiometric measurements do not cancel out interference simultaneously added to the input and voltage reference ports.

Lecture Notes in Computer Science, 2006

Abstract. Being autonomous is one of the biggest challenges for many people with disabilities. Wh... more Abstract. Being autonomous is one of the biggest challenges for many people with disabilities. While wheelchairs enable individuals to move freely, com-puters allow them to communicate, work, etc. by their own. In many cases both devices are controlled by two ...

Waste Management, 2014

Monitoring of the moisture and temperature of composting process is a key factor to obtain a qual... more Monitoring of the moisture and temperature of composting process is a key factor to obtain a quality product beyond the quality of raw materials. Current methodologies for monitoring these two parameters are time consuming for workers, sometimes not sufficiently reliable to help decision-making and thus are ignored in some cases. This article describes an advance on monitoring of composting process through a Wireless Sensor Network (WSN) that allows measurement of temperature and moisture in real time in multiple points of the composting material, the Compo-ball system. To implement such measurement capabilities on-line, a WSN composed of multiple sensor nodes was designed and implemented to provide the staff with an efficient monitoring composting management tool. After framing the problem, the objectives and characteristics of the WSN are briefly discussed and a short description of the hardware and software of the network's components are presented. Presentation and discussion of practical issues and results obtained with the WSN during a demonstration stage that took place in several composting sites concludes the paper.

IEEE Transactions on Electromagnetic Compatibility, 2000

In this paper, we present a frequency-selective probe intended to measure E and H fields simultan... more In this paper, we present a frequency-selective probe intended to measure E and H fields simultaneously in the near-field region. The probe is implemented on a printed circuit board (PCB) that provides some advantages compared to those presented in previous works. The existing theoretical models are adapted in order to include the effect of both PCB trace and dielectric support. The probe is used for in situ electromagnetic compatibility (EMC) characterization of industrial installations, which offers valuable information that cannot be obtained by the usual EMC measurements.

IEEE Transactions on Biomedical Engineering, 2000

The purpose of this paper is to analyze the influence of the metallic structures of a realistic c... more The purpose of this paper is to analyze the influence of the metallic structures of a realistic car body frame on the specific absorption rate (SAR) produced by a cell phone when a complete human body model is placed at different locations inside the vehicle, and to identify the relevant parameters responsible for these changes. The modeling and analysis of the whole system was conducted by means of computer simulations based on the full wave finite-difference time-domain (FDTD) numerical method. The excitation considered was an 835 MHz 2 dipole located as a handsfree communication device or as a hand-held portable system. We compared the SAR at different planes on the human model, placed inside the vehicle with respect to the free space situation. The presence of the car body frame significantly changes the SAR distributions, especially when the dipole is far from the body. Although the results are not conclusive on this point, this change in SAR distribution is not likely to produce an increase above the limits in current guidelines for partial body exposure, but may be significant for whole-body exposure. The most relevant change found was the change in the impedance of the dipole, affecting the radiated power. A complementary result from the electromagnetic computations performed is the change in the electromagnetic field distribution inside a vehicle when human bodies are present. The whole vehicle model has been optimized to provide accurate results for sources placed inside the vehicle, while keeping low requirements for computer storage and simulation time.