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In this document we would like to present our solution for future well-organized online laboratories. This method is currently used at Politehnica University of Bucharest in Romania and thanks to it, faculty staff and students may access equipment via internet to perform experiments and laboratory tasks without being in the physical lab space. Also, remote labs provide additional benefits such as supporting distance learning, improving lab accessibility to handicapped people, and increasing safety for dangerous experimentation. The theme envisages the creation of an integrated platform capable of analyzing, both remotely and locally, the parameters of passive components and circuits. It studies discrete and integrated passive electronic components, considering their characterization, technology, design, modeling, simulation, measurement and use in accordance with the particularities of the electronic circuits in which they are used. The main objective consists in providing remote access to Labs in Electronics & Communications field and motivating students to conduct experiments by arousing their curiosity. To reach the previously set objective, we have designed more experiments related to the field of Electronics and Telecommunications. This lab allows students to perform real time experiments through different devices controls.

The project envisages the realization of a microsystem that can guarantee the control of the pumping mechanism within a microfluidic system. The microfluid system consists of a cavity into which the fluid enters through the inlet microvalve and is pumped through the outlet microvalve. The electromagnetic (EM) micropump system consists of three main components: a microfluidic component, a magneto mechanic actuator, and an electromagnetic component. The control of the pumping mechanism is ensured by an embedded microelectronic system. This ensures proper control of both the inlet and outlet microvalves and the pump diaphragm. The composite membrane structure is made of magnetite composite and patterned in matrix blocks. The injection flow rate of the EM micropump can be controlled by adjusting the input power supplied to the electromagnetic coil, and this is used to improve the injection accuracy of the fluid dosage and have potential in improving the proficiency of the existing fluid delivery system. A control circuit was designed using microcontroller ATMEGA2560 to produce square waves to control coil actuator. The system is designed to be used in many applications especially in medical drug delivery system.

A study was conducted on increasing the current carrying capability of conductor tracks made of electrically conductive composite materials to know the limitations when used in the manufacture of electronic modules by additive techniques. Conductor tracks patterns having three different widths were first produced on dielectric support by screen printing and curing. The study method was an indirect one consisting in measuring the electrical resistance of the tracks of equal lengths. The electrical resistance of each conductor track was measured using the 4-point method. Very good results were obtained for the samples having four times the initial width of the track, but the cost of the material based mainly on silver, increases to the same extent. Next, the same patterns were submitted to an electroless copper plating process and the electrical resistance measurements were performed again. The experiment revealed that the electrical resistances after copper plating show very close values for the same track width, regardless of the material. The conductor tracks were characterized by scanning electron microscopy (SEM EDS).

The paper is a part of a larger study regarding reliability aspects of high power DMOS (Double-diffused MOS) transistors, as part of automotive integrated electronics. When submitted to high transient loads, the junction temperature of these devices suffers large excursion from ambient to 350°C, strongly influencing the reliability. Authors present in the paper the results of thermal transient analysis of a PCB (Printed Circuit Board) test structure containing 8 CERDIP (CERamic Dual In line Package) components on the board. The investigations are performed using FEM (Finite Element Method) analysis, the main results being the time evolutions of temperature in different locations of the board, including the chip active area. These time results are used as input data for thermal impedance calculations and for further simulations based on SPICE type programs.

The paper presents smart blended learning for fostering students’ performance. It uses models of student activity and detects causes of a possible drop out, using learning analytics and real-time data. Taking advantage of embedded sensors (non-invasive, low-cost, flexible and distraction free) built into wearable devices real-time data can be used to support students’ success, well-being and health. In our contribution to the research topic we evaluate the students' experience with smart blended learning using biofeedback methods, sensor data extracted from wearables for five specific lectures, during study periods and in examinations. The preliminary results indicate a correlation between the physiological signals and the grades in examination.

The system is able to identify a vehicle according to the license plate and the model of the car and it decides if the vehicle has or not has access in a limited access area. The access of the vehicle in this area is made by a barrier actuated by a servomotor. If the vehicle information exists in the implemented database, a green LED will light for indicate that the vehicle has access in the area and the barrier will be raised. If the vehicle is not in database, a red LED will light and the position of the barrier will not change.

The choice for continuous solutions that demand connectivity is spreading globally, this paper presents a university program aimed to create an environment where students can develop professional competences through practice. We have designed a pedagogical program able to evaluate, train and generate mechanisms to support learning for students even if they need to work remotely. In this way, we managed to expand digitalization, hybridization and ubiquitous learning; and we promoted internal reflection on the renewal of teaching and learning model. The program is designed to run throughout the 6th semester of bachelor student's courses at electronics universities. Students receive the project theme from teaching stuff, it consist from a complex embedded system, at the beginning of the semester; this is divided and assigned to teams, each consisting of two students. This way the division into smaller projects is promoted, the union of which actually represents the final project. This approach has multiple advantages: each team is provided with the individualization of the theme, but at the same time the teams are working on a complex project, each contributing to it. When solving the projects, the fact that the topics interact means that the students need to cooperate with one another in order to find optimal solutions. These subsystems are assembled at the end of the semester and interconnected using a standard interface without facing problems like the lack of wires or that other teams are using other protocols.

The research was based on determining the most efficient techniques to decrease the number of cables in a system. One interconnection technique that allows a significant reduction of the wire length is the use of the power line as a data bus. The paper is focused on the use of power line communication in the automotive field, to control emissions by preheating the catalytic convertor. The catalytic converter is an element with an essential role in reducing the car emissions. Inside the catalytic convertor take place some chemical reactions at a high level temperature (around 600°C) [1]. The problem occurs when the car is started because the catalytic convertor needs approximately 10 to 15 minutes to reach the optimum operating temperature. By integrating this interconnecting technique in a system of command and control of the heating of a catalytic convertor, it is possible to observe the behavior of the DC power line communication and at the same time to solve the problem of the classical catalytic convertor.

The Education 4.0 process can be used to foster students' performance, to motivate them by means of adaptive and personalized learning, to automate answering routine questions and to improve the quality of online examinations. It releases teachers from routine tasks, and it enables them to be more involved in the individualization of the educational process and in innovation. We apply artificial intelligence methodology to motivate students to improve their performance, and to identify early in course which students are at-risk of dropping out. In the adaptive Education 4.0 loT framework, the environmental and embedded sensors from wearables examine biosignals with biofeedback, such as pulse (HR) and heart rate variability (HRV), thereby increasing students' self-reflection, and allowing for a more personalized learning experience. The first experiments corroborate meaningful correlations between the data-points reached in the self-assessments, and values of the biosignals.

The supercapacitor, the relatively new passive component in the electronic field, has begun drawing attention to more and more users in terms of energy storage and delivery applications in a very short time. Researchers are trying to constantly improve and reduce a number of disadvantages for this component, such as: decrease in equivalent series resistance, increase in maximum working voltage or capacity. All these aspects can be improved only by making different variants of components, from different materials and choosing the variant with the best results. For this, the purpose of this work is to present the realization a supercapacitor, Pouch type cell, by means of the equipment already used in the manufacture of batteries. As materials, will be used for electrodes, aluminum foil on which a porous material will be deposited, and as an electrolyte we will use an ionic liquid, known for its performance regarding much higher working voltage (up to 5V) compared to aqueous electrolytes (maximum 1.2V) or organic electrolytes (maximum 2.7V). Thus, we try to obtain a supercapacitor for which the working voltage exceeds the maximum value encountered so far for a single component and also based on the fact that we have all the information about the realization process we can draw important conclusions about the component made. In this way we can bring improvements to future components, by using other materials instead of those we consider problematic.

The manner in which a secret key is used in symmetric cryptographic systems is a permanent challenge for cryptographers due to its importance in overall security required for information protection. In order to mitigate the success rate of an attacker, a key expansion stage is included in cryptographic algorithms. This article presents an innovative solution that maximizes the key space, without reveal any information to an attacker who might monitor the communication channel. The prerequisites of this approach are the secret keys, a pseudorandom numbers generator and a random number generator, all of these being aggregate by a challenge-response mutual authentication protocol and a permutation function. For an efficient implementation, the already existing conductive mesh and the associated electronic circuits, dedicated to protect the cryptographic module against physical intrusion attempts of an attacker, are used to generate random numbers, without being necessary other electronic circuits. The numbers established as a result of the mutual authentication protocol will be used further to permute the secret key so, after each logical (re)synchronization, different keys will be used in cipher algorithm. Due to this key space extension process, the confusion and diffusion properties belonging to cypher algorithm are improved.

The paper presents the investigation of composite structures made by overlapping two or more layers of resins, including conductive resins, at different time intervals, as well as different temperatures. This situation occurs in the case of a model of implementing an innovative concept of manufacturing electronic modules without using solder alloy, the Occam process. According to this approach, the interconnection structure is arranged on several layers with conductive paths separated from each other by dielectric layers. It is interesting to characterize the interface between layers to determine the possible effect on the reliability of the module. Samples of at least two layers of three types of resins were investigated using Scanning Electron Microscopy/Energy Dispersive X-Ray Spectroscopy analyses. These analyses emphasized there is no chemical bonding at the interface between the layers of resins, but only mechanical. This is a major disadvantage that can lead to the dismantling of the assembly under the action of mechanical forces and environment conditions.

Nowadays the vehicles contains a lot of electronic tehnology and already exists many smart systems mounted on them. The direction of drive the vehicle is determined with the help of the accelerometer. The proposed system aims to increase sensory sensitivity in identifying where the car is in a perimeter when a student learns to drive. This system help the drivers with less experience, such as beginners, so that they acquire driving skills as soon as possible and this system help the drivers to drive safely. It ensures distance monitoring four directions: front, back, left and right of the car. The system alerts the driver both optical and acoustic when the car is very close to an obstacle when the car moves with a speed lower than the proposed threshold.

Polyaniline (PANI) is a valuable, old, complex, organic, nontoxic, cheap, semiflexible, good environmental properties (electrical conductivity value of 10_10 to 10_5 S cm_1), conducting polymer material having interesting properties (and having a huge potential to be applied in industry (especially in microelectronics), beeing among the most studied conducting polymer during the last 50 years.Polyaniline has interesting properties: it has both electronic and ionic conduction, a color changing is observed depending on the degree of its oxidation/reduction state, it has a high chemical and thermal stability, presents piezoresistive properties, and has cytocompatibility. Many of these properties can be controlled by doping/dedoping phenomena. With these remarkable properties, polyaniline is a valuable candidate for large-scale industrial applications, including passive electronic components manufacturing (resistors and capacitors).

The IoT concept keeps the interest of electronics designers for many years. The IoT devices are used in various application domains, such as: consumer, commercial, industrial, infrastructure and medical. They process and communicate data that, in most cases, are confidential or are not intended for the public. The security of the IoT devices has become a major concern for every user. This paper proposes a security system that protects the IoT devices from tampering with no backup power. It consists of an electronic circuit that has two roles: analyzes the physical integrity of the protected device and derivates a key to decrypt the firmware.

The core of this paper is to present an example of use for a growing technology, which is Internet of Things (IoT), with an explicit, complete design and implementation of a custom prototyping embedded system capable of mapping air quality in multiple areas in real time. We designed the system for home use, but also to be mounted in a car or to be transported with the user everywhere, so that not only an area, but also an entire zone to be monitored. Our embedded system is developed on an ATMEGA328PB microcontroller. It combines on a single printed circuit board (PCB) a sensor for atmospheric particles (PM2.5 / PM10), one for measuring temperature and humidity (DHT22), a global positioning module (GPSGY-NEO6MV2) and a module for communications mobile (GSM-SIM800L). The GSM module is used to send measured data from sensors in real time, with precise location, to the server which allows access to monitor an environment through a web interface. The system counts the particles every second, the total mass estimated for PM1.0, PM2.5 and PM10 is averaged for the last 3 seconds and using the Internet of Things (IOT) protocol. The information is sent to the server along with data about temperature and humidity and coordinates received from the GPS module. This way, we provide a general idea of the PM readings in areas where the sensor has traveled.

In conventional RFID applications the total radiated power is constantly focused towards a single area, where are expected objects tagged with transponders. Essentially a transponder needs this energy just for a few milli-seconds. For all the other time the energy could be used for other reasonable purposes, which would lead to a higher energy efficiency. Our proposed solution is Self Switching Antenna (SSA), which is switching in serial manner, each $\tau$ seconds. Each area receives for $\tau$ seconds the total radiated energy and the cycle repeats with a period of T= N x $\tau$. This leads to an unlimited number of areas possible. These areas are geometrically defined and might be independently addressed at a well defined time slot. Such a system may be defined as GDMA communication type (Geometrically Domain Multiple Access).

Power conversion has gained a powerful advantage in terms of efficiency and form factor through the use of planar magnetic structures. Along with the chosen winding method, the properties of magnetic material play a key role in the efficient operation of a transformer. From the perspective of operating at frequencies near MHz domain, the losses in magnetic cores are strongly dependent on the temperature conditions, the value of the saturation induction as well as the hysteresis loop. Taking into consideration the saturation threshold, the maximum value of magnetic intensity H is given by the ratio between current which crosses a number of turns and the magnetic length path. The present study is a continuation of a previous work regarding two proposed models of planar transformers working at frequencies close to 1 MHz.

The core of this paper is to present an example of use for a growing technology, which is Internet of Things, with an explicit, complete design and implementation of a custom prototyping embedded system capable to automatically dispense pills in the right dose at given intervals. We’ve designed the system for use at home and in hospitals by children, adults, the elderly and even by people with visual impairments. The system has been designed to give access to monitor and control through a phone application with no monthly subscription. The user controls the system using the application and on-board keys to set the distribution range of the pills and the number of pills per interval. Also, alerts are sent when the pills were not removed from the tray. The experimental results were obtained by developing the module and using it to dispense pills at certain predefined intervals.