Thin CuInSe2 layers were obtained by “flash” evaporation method, possessed a p-type conductivity and a hole concentration of more than ~ 1019 cm-3. The energy of the intrinsic defects associated with the interstitial selenium atoms is 0.13 eV, and the low values of the charge carriers mobility indicate the presence of a compensation effect.
The paper analyzes the optimal choice of banks of capacitors steps in case of industrial consumers with variable load. The difficulty of establishing scales is that the load varies greatly and that receptors are widespread in terms of location. This paper proposes a method of calculation as to maintain the power factor at the point boundary limits that does not lead to a penalty due to reactive power absorbed. It is based on measurement and verification requirements for each level of the relevant load. Finally it is presented a scheme to automate the steps.
The aim of this work consists in the charaterization of mechnical properties (compressive law of behaviour and elastic properties) of a ceramic foam whose pore volume fraction is about 87%. Compressive behaviour is similar to these of cellular materials (elastic domain, plateau phase and densification successively). Elastic properties determined by 3 different methods (i-from the law of behaviour, ii-by pulse echography technique and iii-by impulse excitation vibration) have shown that the mean value of overall Young’s modulus is in agreement with Ashby’s models of prediction considering the interconnectivity of pores in the microstructure of tested materials.
Zinc phthalocyanine (ZnPc) is an organic p-type semiconductor, whose molecule is a conjugated multicontour system. In order to obtain photovoltaic devices, the costly method of vacuum deposition of ZnPc thin film semiconductors was replaced by the drop casting deposition from solutions. This method allowed the obtaining of Schottky diodes by solution processes with photovoltaic parameters of open circuit voltage and short circuit current density higher than in the case when obtained with thermal vacuum evaporation. In addition, this method is harmless to body and environment, much cheaper and exclude working with toxic substances.
Le composite Ga2O3-Ga2S3-GaS est un matériau photosensible dans la région violette-UV du spectre. Le maximum de la dépendance spectrale à la variation de conductivité électrique se trouve dans la région de 290÷320 nm, la région dans qui se trouve la bande d'absorption de l'ozone et en même temps d’absorption du rayonnement dangereux pour les organismes vivants. Ainsi, les structures de Ga2O3, et Ga2S3 peuvent servir comme récepteurs de l'ozone et de dioxyde de carbone.
Nanosecond Pulsed Electric Fields (nsPEFs) are pulsed electric fields with high-intensities (few MV / m) and ultra-short durations (a few nanoseconds). These electromagnetic fields are used for biomedical applications such as cancer treatment. The application of the nsPEFs can be carried out by different exposure devices. In this article, four wire electrode devices are characterized in the frequency domain to assess their adaptation to nsPEFs exposures. The results show that these devices are capable of applying nsPEFs of 10 ns durations
Titanium dioxide films were deposited on silicon substrates by a PECVD torch. A static mode, with a stationary substrate in front of the plasma, and a dynamic mode, with a moving substrate in front of the plasma along the x axis, were studied. The aim was to replicate, using the dynamic mode, the columnar structure composed of anatase monocristals obtained in static mode. These results showed that the process parameters, as the precursor flow rate and the torch-substrate distance, have a critical role to control the film morphology in dynamic mode to obtain a promising microstructure.
The aim of this study is focused on the elaboration of new bio-based alumina concentrated suspensions with rheological properties adapted to the tape casting process and with low environmental impact. Natural polymers extracted from plants were identified as promising candidates in order to substitute the classical organic additives. Aqueous suspensions were prepared from these bio-polymer additives. Finally, the rheological properties of the suspensions and the mechanical properties of the green and sintered tapes were determined in relation with the nature of bio-polymer additives.
In this article, the goal is to deacidify silica gels containing a large amount of hydrochloric acid necessary for the synthesis of mixed gels. A washing step is added to the gel preparation protocol, in order to remove a certain amount of acid and also to improve the drying, promoting non-cracked bulk gels. The results are promising, which allows to transpose this process to the elaboration of mixed gels.
In this paper, we present a system based on advanced microcontroller in which are implemented a model based on one diode of a photovoltaic generator (PV) and a MPPT (Maximum Power Point Tracking) control P&O (Perturb and Observe). We emulate a PV generator by developing the current-voltage (I / V) characteristics and power-voltage (P/V) characteristics. The integrated MPPT algorithm generates a PWM (Pulse-width Modulation) signal for the maximum power point tracking of the photovoltaic generator according with the temperature and sunshine. The power part being in development, in this phase of the work, we present and compare the (I /V) and (P/V) characteristics and the control PWM signal generated by our system with the results obtained under the Matlab/Simulink environment.
In this paper we analyze from experimental point of view the main parts of a SoLoNOx combustion chamber: premixing zone, combustion primary zone, dilution secondary zone, air inlet, main fuel inlet, pilot fuel inlet, air swirler, hot gas flow to the turbine inlet.
The progress in Nanotechnology has also made its way in the computational tools used in this scientific endeavor. The non-equilibrium Green’s function (NEGF) method is such a technique that has become a standard computational tool in Nanoelectronics. In this communication we present the NEGF method and its applications to electron transport in a multi-layered structure (i. e., double barrier tunneling device) and in a molecule connected to metallic contacts.
One of the common drawbacks in Renewable Energy Sources RES is the power intermittency. In this paper an up to date literature review of hybrid wind-tidal power generation systems will be presented, focusing mainly on using different system configurations to manage and control power fluctuation in hybrid wind-tidal power generation. Furthermore, unit sizing selection; issues findings and challenges in design stages, advantages and critical problems of hybrid energy systems will be addressed.
This article presents the results of the research on the influence of water properties with an electromagnetic field in the range 20-25000 Hz. The dependence of the variation of the electrical conductivity of the distilled water was determined for 60 minutes under the action of the electromagnetic field. It is assumed that long-term changes in water quality mediate the effect of electromagnetic fields on biological systems.
In this paper analyzes some aspects of the regime deformed produced by the controlled power rectifiers on supply networks. It proposes a technical solution, relatively simple and low cost for implementation to reduce the deforming regime and reactive power to the power rectifiers with conventional thyristor (SCR).
Polymeric nanocomposite materials derive from two components: polymers and inorganic materials. These materials have attracted the attention of scientists because of their unexpected properties. Polymeric nanomaterials have a layered structure and present various properties such as: specific surface area, pore diameter, thermal stability, mechanical and flame-retardant properties that can be significantly improved by their processing and used as nanofilters.The layered nanostructure materials involved in this area mainly include silicates, manganese oxides, laminated phosphates, titanates, molybdenum sulphide and laminated double hydroxides (LDH). Among them, LDH, also called anionic clay are considered a class of clays. Anionic clays are mixed hydroxides layered with interlayer space which contain exchangeable anions and water molecules. Depending on the polytype form and composition are used many names for these material. The most used terms being layered double hydroxides - LDH or hydrotalcite-type - HT compounds.
The paper presents the procedure for building a system based on Arduino and various Internet technologies to succeed remotely controlled power supply to some equipment in the house. The paper used an Arduino Ethernet development board, a board with two relays oldest being adapted to the control. The paper presents the algorithm used for processing online data taken from the Arduino board.
The aim of this paper is to analyse the results of the multimedia technologies implementation and the data used for the promotion of Computer Science study programmes at Vasile Alecsandri University of Bacau, Romania. The promotion strategy adopted uses high performance multimedia technologies and integrated Social Media elements as video and web applications. Statistics are being discussed about as well, in order to reflect the results of the promotion strategy.
In recent years, researches regarding the development of new applications of neural networks have intensified. In this paper, the authors describe the way of implementation of a perceptron on a development board Arduino UNO. The perceptron training was programmed to be realized by using the graphic interface Serial Monitor included in the development environment Arduino IDE. The verification of the answer given by the perceptron was realized throughout an electric circuit.
The cultural heritage of a community remains an important mark of its identity. Culture is, in fact, only the result of a sharing: sharing of goods, but also sharing of knowledge and practices. The institution of Intangible Cultural Heritage by Unesco is based on this dialogic character of "common life". Practices and knowledge about certain cultural facts become components of the repertoire of intangible heritage. It includes food practices - the subject of the eCultfood research project. The collection of data, realized by means of audio-video, is completed by digitization: the aim is to create a complex multimedia site, proving the profile of the culinary identity of the department of Bacau.
In this paper was presented a temperature control system in an enclosure by using the Arduino Mega 2560 development board. The temperature in the enclosure was measured with a LM 35 temperature sensor. For the control of the temperature in the enclosure, we used the "Measurement of temperature_Arduino_2015.vi" program made in the LabVIEW 2015 programming environment. This program was implemented and validated on an experimental stand in the Electrical Machines Laboratory from "Vasile Alecsandri" University of Bacau. By using this temperature control system, will be obtained reduction in the amount of electricity needed to heat the enclosure.
The paper presents the authors' original contributions to the synthesis of embedded systems based on programmable logic arrays. An embedded system has one or more central units with a program structure. This allows the optimized design of the instruction set for that central unit. The paper presents the method used to design central units with a dedicated set of instructions. The advantages and disadvantages of the method are discussed and the design steps are presented. We discuss the shortcomings regarding the portability of the programs and we also show the methods of solving this. In the paper there is also an analysis of the structure used for the dedicated set of instructions.
During the last three academic years, between 2014-2017 the Laboratory of our faculty which is involved in Free Software Testing was the scene of a set of experiments în Network Simulations. The goal was to provide a set of training sessions to the students of the F.R. program of The Faculty of Sciences (F.R. means students learning from the distance). Three kinds of software was involved in our test and one had succeeded in being selected as the software support of the Networks Laboratory: CORE. The papers is illustrating the use of CORE în a small network simulation, one of those who will be presented in a book by a romanian editor.
The aim of this paper is to describe and analyze last years romanian policies and e-government solutions in fighting extreme weather, their impact on the population, and future trends. IT warning solutions for severe weather are also presented.
Recent research reveals that other more discrete factors, like “Knowledge-based work (KBW)” have been identified as a potential factor that induces overeating and/or obesity in workers, mostly in women. That might be the explanation for epidemic obesity in person stress-exposed in work-place for a long time. Based on auto-regulation theory, the goal of this paper was to explore the relations between psychological characteristics, mental work-related efforts, and food intake, a cause which is capable to explain the very high incidence and prevalence of epidemic obesity in this kind of population (occupational category). The results are in agreement with the current literature. However, the controlled motivation variable shows no association with bodily satisfaction even though this relationship is well documented in women. Additional researches are needed to total understanding of complex interactions, the reasons underlying this association partially known between KBW, psychological characteristics, and ad libitum food intake.
This study aims to characterize the antimicrobial properties of copper coatings deposited by thermal spraying (plasma and wire-arc) on a wood substrate. The antimicrobial properties of these deposits were evaluated for different bacterial strains: E. coli, S. epidermis, E. faecalis, B. subtilis. The structural characterization of the deposits showed that they were continuous but revealed differences in their chemical composition. These observations were correlated with microbiological results. Deposits obtained after plasma spraying, without copper oxide have less important bactericidal properties.