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The Impact of Government Emergency Ordinance No. 114/2018 on the Profitability of Companies Acting in Energy Domain, Listed on Bucharest Stock Exchange

Abstract

On December 29, 2018, the Government Emergency Ordinance no. 114/2018 has been published. This Ordinance, among others, established a multitude of measures, both economic and fiscal that aimed companies acting in the energy field. The monetary contribution, received from the license holders in the field of energy, was set at the level of 2 %, which means an increase of 20 times of this duty. These companies also have the obligation to sell the natural gas quantities, resulting from the current domestic production activity, at the price of 68 lei / MWh to eligible suppliers and final customers. All these measures have had a direct impact on companies acting in the energy field, affecting their profitability and simultaneously their ability to carry out investment projects. This paper analyzes the way the e companies listed on Bucharest Stock Exchange, acting in energy field, were affected by Government Emergency Ordinance no. 114/2018 measures.

Open access
The Impact of Microclimate Parameters on Odour Emissions from Pig Production in Spring

Abstract

The aim of this study was to examine the impact of inside temperature and relative humidity, ventilation rate and gas concentrations (NH3, N2O, CO2) on odour emissions from deep-litter piggery. The studied facility had temperature-controlled mechanical ventilation. The measurements were conducted from March to June 2014. During the research, selected microclimate parameters, as well as number and mass of animals were monitored and air samples were collected (two samples of air in each series of measurements). Temperature and relative humidity were measured using Testo 435-4 multifunctional measuring instrument. To measurements of gas concentrations was used the photo-acoustic spectrometer Multi Gas Monitor Model 1312. The concentration of odours in the air samples was determined by dynamic olfactometry with the TO 8 olfactometer, according to PN-EN 13725:2007. The odour concentration ranged from 450 to 2004 ouE · m–3 (mean 1048 ouE · m–3) and the mean odour emission factor was from 5.76 to 46.79 ouE · (s · pig)−1 (mean 20.93 ouE· (s · pig)−1.The statistical analysis showed that the inside temperature explained most of the variability of the odour concentration and the relationship was described by equation: cod = 5634 – 197 Tinside (R 2 = 0.82, p ≤ 0.05). For odour emission factor, two parameters: the inside temperature and ventilation rate, explained most of the variability, according to the equation: EFod = 108 + 1939 VR – 5.5 Tinside (R 2 = 0.81, p ≤ 0.05).

Open access
Improvement of the National Research, Development and Innovation Strategy 2014-2020 in Comparison with the National Research, Development and Innovation Strategy 2007-2013

Abstract

The European Union regularly develops research, development, innovation (RDI) strategies for seven years for member countries. Romania benefited from the first RDI strategy during the period 2000-2007, during which our country was trying to meet the conditions of EU accession. Romania is a member of the EU since 1st January 2007 and started, based on the EU’s RDI strategy, to develop its own strategy. The present paper aims to analyze the achievement of the general and specific objectives established by National Strategy for Research, Development and Innovation (NSRDI) 2007-2013, the evolution of the results 2014-2017 and what could be the measures and programs taken by Romania in 2019-2020 to bring our country closer to achieving the established objectives through NSRDI for the period 2014-2020.

Open access
Interlaboratory Comparison of Thermal AC Voltage Standards

Abstract

The article presents results of comparison of the thermal converter of nominal input voltages equal to 10 V from the set of Polish National AC voltage standards, maintained at the Central Office of Measures in Warsaw, with the primary AC voltage 5 V standard, developed and maintained at the AC-DC Transfer Laboratory of the Department of Measurement Science, Electronics and Control at the Faculty of Electrical Engineering of the Silesian University of Technology in Gliwice.

Open access
Investigating the Effect of Nanomaterials on Resistance Parameters of Clay Soil

Abstract

In recent years, nano technology has been significantly implemented in geotechnical engineering, especially for soil remediation. Using this technology has improved soil resistance parameters and led to the stabilization of many problematic soils. Clay soils, due to their nature, have a large dispersion on the surface of the earth. The widespread dispersion of these types of soils in the site of structures, describes the necessity of studying and investigating new methods of improving and amending the resistive properties of these soils. This research is a review of the use of nanotechnology for the improvement of soil resistive properties by geotechnical researchers.

Open access
Investigating the Performance of Isolation Systems in Improving the Seismic Behavior of Urban Bridges. A Case Study on the Hesarak Bridge

Abstract

This paper investigates the influence of isolation systems on the seismic behavior of urban reinforce concrete bridge. The performance of the Hesarak Bridge constructed in Karaj city, Iran with two isolation systems; i.e. the existing elastomeric rubber bearing (ERB) and a proposed lead rubber bearing (LRB) is discussed. The numerical model was implemented in the well-known FEM software CSIBridge. The isolated bridge has been analyzed using nonlinear time history analysis method with seven pairs of earthquake records and the results are compared for the two isolation systems. The LRB isolators are shown to have superior seismic performance in comparison with the existing ERB systems based on the response evaluation including force on the isolator, pier base shear, deck acceleration, bending moment, pier displacement, and energy dissipation.

Open access
Investigation of Biosensor Potential Component Stability Caused by Influence of External Condition

Abstract

The analysis of UV-VIS spectrum was used for testing changes through 36 days and the impact of external conditions (reduced temperature (R), microwave radiation (M) and normal conditions (NC) for comparisons) on the stability of: BSA and BSA-Fe2+ complexes after different treating procedure. The increase of BSA absorption with increasing concentration of Fe2+ was observed. Increased absorption of BSA, and BSA-Fe2+ with time, related probably to conformational changes present in the protein and changes in electrostatic reactions within the BSA-Fe2+ complexes. Examination of the impact of an external factor on stabilization of the protein and complexes showed a tendency to keep the stability under reduced temperature and a trend with accelerated protein and complex aging under microwave radiation. The observed tendencies to changes under the influence of external factors became more significant in time. These effects were most probably related to changes of the protein structure and time, while the observed trend of accelerating the changes was impacted by the applied external factors.

Open access
Kinetics and Thermodynamics of Dispersed Oil Sorption by Kapok Fiber

Abstract

This work was aimed at evaluating the sorption of dispersed oil by kapok fiber. The physicochemical characteristics of kapok fiber were investigated using BET, SEM, FTIR, XRD, contact angle and elemental analysis. The oil droplet size distribution at different temperatures was analysed using a Coulter counter, and its relationship with sorption was investigated. The effects of dosage, hydraulic retention time and temperature, on the sorption performance were studied. The result indicates that the sorption of dispersed oil by kapok fiber is spontaneous, endothermic and agreed with the pseudo-first-order reaction kinetics. The amount of oil that could be removed is about 28.5 %, while that of water is less than 1 % of the original amount (0.5 dm3). Kapok is a promising natural hydrophobic fiber for dispersed oil removal from oily wastewater.

Open access
A Liquid Metal Flow Between Two Coaxial Cylinders System

Abstract

The Taylor-Couette flow between two rotating coaxial cylinders remains an ideal tool for understanding the mechanism of the transition from laminar to turbulent regime in rotating flow for the scientific community. We present for different Taylor numbers a set of three-dimensional numerical investigations of the stability and transition from Couette flow to Taylor vortex regime of a viscous incompressible fluid (liquid sodium) between two concentric cylinders with the inner one rotating and the outer one at rest. We seek the onset of the first instability and we compare the obtained results for different velocity rates. We calculate the corresponding Taylor number in order to show its effect on flow patterns and pressure field.

Open access
Low Power Full Adder Design Using PTM Transistor Model

Abstract

At present the processing power of the digital electronic chip is enormous and that has been possible because of the continuous improvement of the design methodology and fabrication technology. So, the data processing capability of the chip is increased significantly. Data processing in the electronic chip means the arithmetic operation on that data. For that reason, ALU is present in any processor. Full adder is one of the critical components of arithmetic unit. Improvement of the full adder is necessary for improving the computational performance of a chip. In order to design an efficient full adder, designer should choose an appropriate logic style. In this research, two new model of full-adder circuits are designed and analyzed using Pass Transistor logic in order to reduce power consumption and increase operational speed. The first proposed adder consists of 8 transistors and the second one consists of 10 transistors. LTSPICE is employed for simulating the proposed circuits using16nm low power high-k strained silicon transistor model. The overall performance of the proposed adder circuits and comparative results demonstrate the superiority of the proposed model.

Open access