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Arcire Alexandru, Olariu Marius-Andrei, Mihalache George
Exploring the Physiosorption Mechanism of Pristine Onion-like Carbons (OLCs) as Gas Sensitive Element

Although the response mechanism of carbon nanotubes (CNTs) based sensors exposed to a variety of gases has been extensively discussed and studied, pristine onion-like carbon (OLCs), part from the same class of fullerenes, have not been fully investigated as sensing application. A room-temperature working chemiresistor based on onion-like carbons (OLCs) as sensing element with good sensitivity has been developed and tested with the main purpose of being implemented within the next generation of gas sensors. Many industries require a room temperature working gas sensor without an external heating source: leakage detections of explosive gases (such as hydrogen), detection of flammable gases and explosives in plants, biomedicine and pharmaceutics, monitor combustibles, early detection of fires, realtime detections of toxic or pathogenic gases in industries, ambient environmental monitoring and control. One industry that would also benefit from development of such a sensor is the food industry which requires a smart label that warns the consumer on the presence of toxic substances to avoid ingestion of contaminated food. Ingestion of food contaminated with different chemicals due to a malfunctioned manufacturing process or due to food spoilage from an improper storage could trigger severe trauma within human body.

Filippo Attivissimo, Attilio Di Nisio, Mario Savino, Maurizio Spadavecchia
Smart Grid Performance Indicators

In this paper a review of smart grid performance indicators is provided. The objectives of smart grids are discussed with the aim of clarifying the evaluation criteria which arises from them. Several metrics are presented, illustrating drawbacks and difficulties in their calculation. The evaluation of Demand Response performance is analyzed in order togive further insights on smart grids performance assessment.

M. Macek-Krzmanc, H. Ursic Nemevsek, D. Suvorov, R. Ciobanu
Size- and Shape-Controlled Synthesis of Ferroelectric Plate-like Particles and Their Piezoelectric Characteristics

Ba1-xSrxTiO3 plate-like particles were prepared by the topochemical transformation of the Bi4Ti3O12 template plates in the molten salt. During the conversion, which took place at 900 °C in the presence of high access of BaCO3 and SrCO3 (Bi4Ti3O12: (BaCO3+SrCO3)=1:10) with the initial Ba:Sr molar ratios equal to 0.98:0.02 and 0.9:0.1, the precursor plate shape was well preserved especially in terms of side length, while the average thicknesses of the final perovskite plates were higher compared to that of template. Energy dispersive spectroscopy (EDS) revealed that the initial Ba:Sr ratio was not maintained during the transformation, namely Sr incorporated more than Ba. The initial Ba:Sr=0.98:0.02 and 0.9:0.1 ratios resulted in the tetragonal Ba0.98Sr0.06Bi0.02Ti0.97O3 and cubic Ba0.79Sr0.24Bi0.02Ti0.97O3 perovskite plates, respectively.
Local Ferroelectric/piezoelectric hysteresis loops that were obtained using a piezoresponse-force microscope (PFM), indicated the significant ferroelectric response of [001] preferentially oriented µm-sized Ba0.98Sr0.06Bi0.02Ti0.97O3 plates.

Oana Beniugă, Răzvan Beniugă
Assessing Operational Planning Performance among Wind Power System based on N-1criterion

The current paper presents an operational planning for wind power system, in terms of safe and reliable power system operation. To ensure operational performance in the control area, based on N-1 criterion, in this paper are highlighted the main security criterions, issues related on correcting or remedial actions, as well as the basic requirements for its implementation in the system. In the paper was simulated a contingency case using Power World simulator 5 bus system in order to achieve an operational planning performance for a wind farm placement.

Imrich Andráš, Pavol Dolinský, Linus Michaeli, Ján Šaliga
Microphone Array Speech Sensing and Dereverberation with Linear Prediction

The subject of this paper is the algorithm for enhancement of reverberant speech using linear prediction. Basic mechanisms of reverberation and their influence on speech signal are reviewed in the introduction. The algorithm with modification and averaging of glottal cycles is proposed, aimed for dereverberation of speech sensed by a microphone array. This algorithm is successful with high levels of noise and reverberation while maintaining computational feasibility.

Emil Vremera, Luciano Brunetti
Primary RF-Power Standard Realization in a Single-step Measurement Process

The RF power standard realized by the microcalorimeter technique has many problems related to the measurement time and the necessity of operating the measurements in two steps, measurement and calibration. In the paper, a new type is proposed of dry microcalorimeter, which has hardware facilities that allow a self-calibration of the system through convenient algorithms and without dismounting/mounting operation. A shorter measurement time without accuracy loss is the most significant result obtainable, provided that the manner changes in which the primary broadband RFpower standards are considered and designed.

Calin Rugina, Olga Plopa, Alexandra Iulia Vizitiu
Mobile Applications for Smart Notifications

The central part of the mobile experience of the consumer is the notification system. Through mobile applications can be delivered rich and contextual content to any person who has installed a specific application. The smart notifications are the result of a complex, logical reaction in some specific situations, look and feel more like a note from your assistant or another human being. A smart notification received on a mobile device can trigger an action on device in background or use human interaction. Start from this fact the mobile device became from a receiver an intelligent tool.

Radu Ilinca, Octavian Doaga
Software Approach in Noise Reduction on an ECG Acquisition Platform

Given the higher and higher incidence of heart related diseases, including the social costs, the early diagnosis becomes increasingly important. The ECG technique is a very useful diagnosis tool. It is relatively inexpensive, irradiation-free and readily available. One of the main issues to tackle when developing an ECG signal acquisition device is to ensure noise and artefact removal. This paper introduces a filtering solution based on a combination of a high pass filter and a low pass filter.

Filippo Spertino, Alessandro Ciocia,Paolo Di Leo, GaetanoIuso, Gabriele Malgaroli, Luca Roberto
Experimental testing of a horizontal-axis wind turbine to assess its performance

This paper describes a test procedure to investigate the performance of a micro wind turbine with horizontal-axis. A 3D model of a rotor with five blades has been designed by a MATLAB software; its airfoil is optimized to efficiently work at low wind speed. The rotor is coupled to an electric generator and this equipment is tested in a wind tunnel. An anemometer is used to measure and set the desired wind speeds. Electric quantities, i.e., voltage, current and power, are acquired by a digital multimeter. A variable resistance is used to change the operating point of the generator. Preliminary results are reported that refer to the application of the proposed test procedures to a wind turbine with a 0.2 m swept area.

Nuno M. Rodrigues, Fernando M. Janeiro, Pedro M. Ramos
Low Pass Digital Filter Delay Compensation for Accurate Zero Cross Detection in Power Quality

–Zero crossing detection with a low pass filter is a common method used to estimate a signal frequency or period when the signal is affected by noise, harmonics or other parasitic frequencies. This method is often used in power quality measurements due to the typical disturbances of the electrical power grid signals and is for example, suggested in IEC 61000-4-30 for power quality frequency estimation. Zero crossing is also needed to evaluate RMS events since RMS evaluation must be synchronized with the input signal zero crossings. However, the filter introduces a delay which affects the accuracy of the RMS evaluation timestamp. High accuracy power quality measurement systems are expensive but their usage has significantly increased in recent years.To create low cost power quality analysers, a solution based on a digital lowpass filter to detect zero crossings and measure signal characteristics such as the RMS value or distortionswith accurate timestamps, is analysed in this paper.

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