Silviu Ionita - Academia.edu (original) (raw)

Papers by Silviu Ionita

Research paper thumbnail of Chapter Automation of the Expertise of the Roman Mosaic Arts in Constanta: Analytical and Statistical Models for a Fuzzy Inference-Based System

The biggest problem faced by the specialists in the field of cultural heritage is the identificat... more The biggest problem faced by the specialists in the field of cultural heritage is the identification of the original elements for their separation from the large mass of the mosaic components that come from completions of the different restoration works. This chapter deals with analytical models for statistical evaluation of the morphological and chromatic characteristics that represent suitable metrics for making decisions in the field of cultural heritage. A classifier model based on fuzzy logical inference, which integrates discrete and statistical characteristics of the mosaic components, is presented. The classification will be done in a space of conventional measures (metrics) for identifying and separating the mosaic components. The exemplification of the method is made on the Roman Mosaic of Constanta, a historical monument that is currently in an advanced stage of deterioration and which requires urgent restoration-conservation interventions. This artifact dates from the th...

Research paper thumbnail of Electrical Model of the Human Head-Circuit Parameters

2020 43rd International Spring Seminar on Electronics Technology (ISSE), 2020

The growing interest for BCI applications (Brain Computer Interface) as well as more ambitious pr... more The growing interest for BCI applications (Brain Computer Interface) as well as more ambitious projects for the development of neuromorphic structures requires an intense research on the electrical activity of the human brain. The brain represents a complex structure of circuits being a relevant reference for the technology of interconnected and packaging in electronics. This paper presents a contribution to the modeling of the human head from the electrical point of view of the propagation properties of the electrical signals, taking into account also the biological structural complexity of the head composed of heterogeneous tissues. It aims to model with passive circuits by evaluating the equivalent impedances of the tissues crossed by electrical biocurrents. In this paper are presented theoretical assessments based on simulated circuit models and electrical parameters reported in the specialized literature. These results are compared with measurements made with a precision impedance bridge, in standard EEG capture points.

Research paper thumbnail of NQR detector: HW solutions and constructive issues

2017 9th International Conference on Electronics, Computers and Artificial Intelligence (ECAI), 2017

One of the most important issues that define the quality of life is the security and security of ... more One of the most important issues that define the quality of life is the security and security of the people against the current threats mainly coming from terrorism. Traffic with narcotics and the irresponsible consumption of some drugs are also serious problems for humanity. The science and technology is on the permanent race to help authorities combat illegal activities such as explosives and narcotics before they produce the effects. The equipment that helps combat these threats should meet several requirements such as sensitivity, accuracy — in terms of specificity and false alarm rate, and time of detection. In this paper we present our work to develop an original equipment for scanning suspect packages to detect the strongest explosives and also some narcotics exploiting the phenomenon of Nuclear Quadrupole Resonance (NQR). The HW solution is presented as well as the main constructive aspects of the prototype are discussed. In this paper are provided results of tests using two reference substances containing 14N: sodium nitrite and paracetamol.

Research paper thumbnail of Intelligent Image Processing and Optical Means for Archeological Artifacts Examination

Advanced Methods and New Materials for Cultural Heritage Preservation [Working Title], 2019

Research paper thumbnail of Autonomous vehicles: from paradigms to technology

IOP Conference Series: Materials Science and Engineering, 2017

Research paper thumbnail of Some highlights on fuzzy systems and data mining

Journal of Intelligent & Fuzzy Systems, 2016

Research paper thumbnail of Representative examples of implementing educational robotics in school based on the constructivist approach

Proceedings of the …, 2008

Research paper thumbnail of Introducing robotics to teachers and schools: experiences from the TERECoP project

Proceedings of the …, 2010

Research paper thumbnail of Low-Speed Sensorless Control of PMSM Motor Drive Using a Nonlinear Approach Backstepping Control: Fpga-Based Implementation

Research paper thumbnail of A Neuronal Model of the Primary Visual Cortex: Simulation of Visual Evoked Potentials

2021 13th International Conference on Electronics, Computers and Artificial Intelligence (ECAI), 2021

The paper describes a theoretical model for simulating electrical signals in specialized cortical... more The paper describes a theoretical model for simulating electrical signals in specialized cortical areas using artificial neuron connections. The study focuses on the structure of the visual cortex and the development of an elementary neural model of the primary visual cortex (V1) responsible for processing contrast visual stimuli type. It’s proposed a basic artificial neural structure composed by connecting representative neurons in V1 capable of generating visual evoked potentials (VEP) responses. The reference response model utilized is the P100 wave that appears unconditionally at people with normal vision to visual stimuli such as flashes or contrast reversal. It was considered that the electrical activity of the primary visual cortex is due to the functioning of a set of excitatory and inhibitory neurons and so, it was simulated the VEP signal with simple type neurons.

Research paper thumbnail of The use of homodyne detection for measuring small frequency differences between two RF oscillators

In this paper we present an experimental set-up for measuring small frequency differences between... more In this paper we present an experimental set-up for measuring small frequency differences between two RF oscillators [1] by using a homodyne detection scheme [2]. To emulate the oscillators, we used two RF sources whose output signals were mixed and then the low frequency components at the mixer's output was measured with a network frequency analyzer. The purpose of these experiments was to evaluate a possible method to discriminate the resonance frequency change of a TF-BAR sensor as a response to its contamination with certain substances.

Research paper thumbnail of Automation of the Expertise of the Roman Mosaic Arts in Constanta: Analytical and Statistical Models for a Fuzzy Inference-Based System

Research paper thumbnail of Low-Speed Sensorless Control of PMSM Motor drive Using a NONLINEAR Approach BACKSTEPPING Control: FPGA-Based Implementation

Research paper thumbnail of Electronic Circuit for Differential Measurement using Resonant Sensors: Designing Approach

2021 13th International Conference on Electronics, Computers and Artificial Intelligence (ECAI)

In this paper we present the design of an electronic circuit which implements a differential meas... more In this paper we present the design of an electronic circuit which implements a differential measurement technique for detecting the presence of an explosive substance by using resonant sensors. Two TF-BAR sensors, with resonance frequencies of about 2 GHz, are employed for this purpose: an active one, which is exposed to the target substance and whose mass changes due to the molecules of that substance attaching to it, and a reference one, which is not exposed to the target substance and whose mass does not change. Due to the mass modification, the resonance frequency of the active sensor slightly changes. The purpose of the presented circuit is to measure this tiny frequency deviation by comparing the resonance frequencies of the two sensors. If both sensors are operated at the same temperature and humidity conditions, the measured frequency deviation is proportional with the amount of mass attached to the active sensor. In the proposed design, we use a frequency-to-voltage converter to translate this frequency deviation into a useful output signal. We present hereinafter the development of the electrical schematics and the simulations results of the functional blocks for the proposed measuring circuit.

Research paper thumbnail of Theoretical and Practical Aspects in the Design and Construction of Active Electrodes for EEG

2020 IEEE 26th International Symposium for Design and Technology in Electronic Packaging (SIITME), 2020

This paper gives details about an approach for the development of an active electrode designed to... more This paper gives details about an approach for the development of an active electrode designed to capture electrical signals of the brain. A comparative analysis of the electrode-skin interface made for wet electrodes and also for a dry electrode based on conductive felt is considered. A laboratory model of a dry active electrode was built and evaluated as well in this project.

Research paper thumbnail of An optimized NQR spectrometer for detection of prohibited substances

Measurement

Abstract Nuclear quadrupole resonance is a radio frequency spectroscopic technique which offers h... more Abstract Nuclear quadrupole resonance is a radio frequency spectroscopic technique which offers highly specific detection and is used in applications such as chemical analysis and security screening. This paper proposes a 14N nuclear quadrupole resonance system designed to detect prohibited substances in the frequency range of 0.4–6 MHz, using low-power and frequency sweeping excitation. The paper presents the system’s components and several technical solutions for noise reduction during data acquisition such as the use of fiber optic communication or battery-powered low-noise amplifiers. The detection system’s performance is evaluated using sodium nitrite and paracetamol, showing that the maximum detection distance for paracetamol is 2 cm and the minimum detection limit for sodium nitrite is 1 g at 7W transmitted power. Several solutions are proposed to further improve the detection system.

Research paper thumbnail of Real-time audio effects with DSP algorithms and DirectSound

Proceedings of the 2014 6th International Conference on Electronics, Computers and Artificial Intelligence (ECAI), 2014

This paper is focused on the software implementation of DSP oriented algorithms for different aud... more This paper is focused on the software implementation of DSP oriented algorithms for different audio effects, like Echo, 3-Tap Echo, Vibrato, Tremolo and Chorus. The main contribution of this research consists in a software application which is able to process in real time the audio signals received from the electric guitar using PC sound card. In addition, the application also includes a digital filter class used for implementation of a low pass filter as well as other filter types, a tone generator and the options for storing the sound samples in a .wav file. The application is written in C# language which uses DirectSound library in order to process the sound samples on a low level.

Research paper thumbnail of The fractal attractors in dynamic of the systems

flsi.cird.or.jp

The chaos is the Disorder State of the matter. It is a fundamental state with the mythological co... more The chaos is the Disorder State of the matter. It is a fundamental state with the mythological connotation as an initial before the birth of Universe. There are two major kinds of phase dynamics: the regular dynamics and the stochastic dynamics (described of haphazard functions). Between ...

Research paper thumbnail of Field-Programmable Analog Filters Array with Applications for Fuzzy Inference Systems

Fourth International Conference on Hybrid Intelligent Systems (HIS'04), 2004

Research paper thumbnail of The fuzzy model for aircraft landing control

Advances in Soft Computing—AFSS 2002, 2002

Abstract. This paper deals the issue of aircraft landing maneuvers from the fuzzy logic perspecti... more Abstract. This paper deals the issue of aircraft landing maneuvers from the fuzzy logic perspective. Generally this part of flight needs to be strongly assisted by human pilot. Our purpose is to evaluate the output parameters from a fuzzy system. We have developed a fuzzy ...

Research paper thumbnail of Chapter Automation of the Expertise of the Roman Mosaic Arts in Constanta: Analytical and Statistical Models for a Fuzzy Inference-Based System

The biggest problem faced by the specialists in the field of cultural heritage is the identificat... more The biggest problem faced by the specialists in the field of cultural heritage is the identification of the original elements for their separation from the large mass of the mosaic components that come from completions of the different restoration works. This chapter deals with analytical models for statistical evaluation of the morphological and chromatic characteristics that represent suitable metrics for making decisions in the field of cultural heritage. A classifier model based on fuzzy logical inference, which integrates discrete and statistical characteristics of the mosaic components, is presented. The classification will be done in a space of conventional measures (metrics) for identifying and separating the mosaic components. The exemplification of the method is made on the Roman Mosaic of Constanta, a historical monument that is currently in an advanced stage of deterioration and which requires urgent restoration-conservation interventions. This artifact dates from the th...

Research paper thumbnail of Electrical Model of the Human Head-Circuit Parameters

2020 43rd International Spring Seminar on Electronics Technology (ISSE), 2020

The growing interest for BCI applications (Brain Computer Interface) as well as more ambitious pr... more The growing interest for BCI applications (Brain Computer Interface) as well as more ambitious projects for the development of neuromorphic structures requires an intense research on the electrical activity of the human brain. The brain represents a complex structure of circuits being a relevant reference for the technology of interconnected and packaging in electronics. This paper presents a contribution to the modeling of the human head from the electrical point of view of the propagation properties of the electrical signals, taking into account also the biological structural complexity of the head composed of heterogeneous tissues. It aims to model with passive circuits by evaluating the equivalent impedances of the tissues crossed by electrical biocurrents. In this paper are presented theoretical assessments based on simulated circuit models and electrical parameters reported in the specialized literature. These results are compared with measurements made with a precision impedance bridge, in standard EEG capture points.

Research paper thumbnail of NQR detector: HW solutions and constructive issues

2017 9th International Conference on Electronics, Computers and Artificial Intelligence (ECAI), 2017

One of the most important issues that define the quality of life is the security and security of ... more One of the most important issues that define the quality of life is the security and security of the people against the current threats mainly coming from terrorism. Traffic with narcotics and the irresponsible consumption of some drugs are also serious problems for humanity. The science and technology is on the permanent race to help authorities combat illegal activities such as explosives and narcotics before they produce the effects. The equipment that helps combat these threats should meet several requirements such as sensitivity, accuracy — in terms of specificity and false alarm rate, and time of detection. In this paper we present our work to develop an original equipment for scanning suspect packages to detect the strongest explosives and also some narcotics exploiting the phenomenon of Nuclear Quadrupole Resonance (NQR). The HW solution is presented as well as the main constructive aspects of the prototype are discussed. In this paper are provided results of tests using two reference substances containing 14N: sodium nitrite and paracetamol.

Research paper thumbnail of Intelligent Image Processing and Optical Means for Archeological Artifacts Examination

Advanced Methods and New Materials for Cultural Heritage Preservation [Working Title], 2019

Research paper thumbnail of Autonomous vehicles: from paradigms to technology

IOP Conference Series: Materials Science and Engineering, 2017

Research paper thumbnail of Some highlights on fuzzy systems and data mining

Journal of Intelligent & Fuzzy Systems, 2016

Research paper thumbnail of Representative examples of implementing educational robotics in school based on the constructivist approach

Proceedings of the …, 2008

Research paper thumbnail of Introducing robotics to teachers and schools: experiences from the TERECoP project

Proceedings of the …, 2010

Research paper thumbnail of Low-Speed Sensorless Control of PMSM Motor Drive Using a Nonlinear Approach Backstepping Control: Fpga-Based Implementation

Research paper thumbnail of A Neuronal Model of the Primary Visual Cortex: Simulation of Visual Evoked Potentials

2021 13th International Conference on Electronics, Computers and Artificial Intelligence (ECAI), 2021

The paper describes a theoretical model for simulating electrical signals in specialized cortical... more The paper describes a theoretical model for simulating electrical signals in specialized cortical areas using artificial neuron connections. The study focuses on the structure of the visual cortex and the development of an elementary neural model of the primary visual cortex (V1) responsible for processing contrast visual stimuli type. It’s proposed a basic artificial neural structure composed by connecting representative neurons in V1 capable of generating visual evoked potentials (VEP) responses. The reference response model utilized is the P100 wave that appears unconditionally at people with normal vision to visual stimuli such as flashes or contrast reversal. It was considered that the electrical activity of the primary visual cortex is due to the functioning of a set of excitatory and inhibitory neurons and so, it was simulated the VEP signal with simple type neurons.

Research paper thumbnail of The use of homodyne detection for measuring small frequency differences between two RF oscillators

In this paper we present an experimental set-up for measuring small frequency differences between... more In this paper we present an experimental set-up for measuring small frequency differences between two RF oscillators [1] by using a homodyne detection scheme [2]. To emulate the oscillators, we used two RF sources whose output signals were mixed and then the low frequency components at the mixer's output was measured with a network frequency analyzer. The purpose of these experiments was to evaluate a possible method to discriminate the resonance frequency change of a TF-BAR sensor as a response to its contamination with certain substances.

Research paper thumbnail of Automation of the Expertise of the Roman Mosaic Arts in Constanta: Analytical and Statistical Models for a Fuzzy Inference-Based System

Research paper thumbnail of Low-Speed Sensorless Control of PMSM Motor drive Using a NONLINEAR Approach BACKSTEPPING Control: FPGA-Based Implementation

Research paper thumbnail of Electronic Circuit for Differential Measurement using Resonant Sensors: Designing Approach

2021 13th International Conference on Electronics, Computers and Artificial Intelligence (ECAI)

In this paper we present the design of an electronic circuit which implements a differential meas... more In this paper we present the design of an electronic circuit which implements a differential measurement technique for detecting the presence of an explosive substance by using resonant sensors. Two TF-BAR sensors, with resonance frequencies of about 2 GHz, are employed for this purpose: an active one, which is exposed to the target substance and whose mass changes due to the molecules of that substance attaching to it, and a reference one, which is not exposed to the target substance and whose mass does not change. Due to the mass modification, the resonance frequency of the active sensor slightly changes. The purpose of the presented circuit is to measure this tiny frequency deviation by comparing the resonance frequencies of the two sensors. If both sensors are operated at the same temperature and humidity conditions, the measured frequency deviation is proportional with the amount of mass attached to the active sensor. In the proposed design, we use a frequency-to-voltage converter to translate this frequency deviation into a useful output signal. We present hereinafter the development of the electrical schematics and the simulations results of the functional blocks for the proposed measuring circuit.

Research paper thumbnail of Theoretical and Practical Aspects in the Design and Construction of Active Electrodes for EEG

2020 IEEE 26th International Symposium for Design and Technology in Electronic Packaging (SIITME), 2020

This paper gives details about an approach for the development of an active electrode designed to... more This paper gives details about an approach for the development of an active electrode designed to capture electrical signals of the brain. A comparative analysis of the electrode-skin interface made for wet electrodes and also for a dry electrode based on conductive felt is considered. A laboratory model of a dry active electrode was built and evaluated as well in this project.

Research paper thumbnail of An optimized NQR spectrometer for detection of prohibited substances

Measurement

Abstract Nuclear quadrupole resonance is a radio frequency spectroscopic technique which offers h... more Abstract Nuclear quadrupole resonance is a radio frequency spectroscopic technique which offers highly specific detection and is used in applications such as chemical analysis and security screening. This paper proposes a 14N nuclear quadrupole resonance system designed to detect prohibited substances in the frequency range of 0.4–6 MHz, using low-power and frequency sweeping excitation. The paper presents the system’s components and several technical solutions for noise reduction during data acquisition such as the use of fiber optic communication or battery-powered low-noise amplifiers. The detection system’s performance is evaluated using sodium nitrite and paracetamol, showing that the maximum detection distance for paracetamol is 2 cm and the minimum detection limit for sodium nitrite is 1 g at 7W transmitted power. Several solutions are proposed to further improve the detection system.

Research paper thumbnail of Real-time audio effects with DSP algorithms and DirectSound

Proceedings of the 2014 6th International Conference on Electronics, Computers and Artificial Intelligence (ECAI), 2014

This paper is focused on the software implementation of DSP oriented algorithms for different aud... more This paper is focused on the software implementation of DSP oriented algorithms for different audio effects, like Echo, 3-Tap Echo, Vibrato, Tremolo and Chorus. The main contribution of this research consists in a software application which is able to process in real time the audio signals received from the electric guitar using PC sound card. In addition, the application also includes a digital filter class used for implementation of a low pass filter as well as other filter types, a tone generator and the options for storing the sound samples in a .wav file. The application is written in C# language which uses DirectSound library in order to process the sound samples on a low level.

Research paper thumbnail of The fractal attractors in dynamic of the systems

flsi.cird.or.jp

The chaos is the Disorder State of the matter. It is a fundamental state with the mythological co... more The chaos is the Disorder State of the matter. It is a fundamental state with the mythological connotation as an initial before the birth of Universe. There are two major kinds of phase dynamics: the regular dynamics and the stochastic dynamics (described of haphazard functions). Between ...

Research paper thumbnail of Field-Programmable Analog Filters Array with Applications for Fuzzy Inference Systems

Fourth International Conference on Hybrid Intelligent Systems (HIS'04), 2004

Research paper thumbnail of The fuzzy model for aircraft landing control

Advances in Soft Computing—AFSS 2002, 2002

Abstract. This paper deals the issue of aircraft landing maneuvers from the fuzzy logic perspecti... more Abstract. This paper deals the issue of aircraft landing maneuvers from the fuzzy logic perspective. Generally this part of flight needs to be strongly assisted by human pilot. Our purpose is to evaluate the output parameters from a fuzzy system. We have developed a fuzzy ...