Experimental Verification of the Impact of the 2nd Order Injected Signals on Doherty Amplifiers Nonlinear Distortion

In this paper, an asymmetrical Doherty amplifier fabricated in microstrip technology is tested in the experiments to verify the impact of the 2nd order signal for the linearization prepared in baseband. The measurement set-up consists of three USRPs programmed by LabVIEW to generate the useful 64QAM signal and the signals for linearization that are set in amplitude and phase and modulate the 2nd harmonic of fundamental carrier. The USRPs instruments should be synchronized for performing measurements for two scenarios: the signals for linearization are injected at input of the transistor within the main Doherty amplifier or are injected at its output

Vehicle emission survey and modeling in the context of street network traffic flow modeling

Upotreba transportnih modela za procene emisija predstavlјa važan deo procesa održivog planiranja saobraćaja većih urbanih područja . Procena uticaja saobraćajnih rešenja na životnu sredinu je jedna od tri osnovne komponente održivosti. Prethodna praksa u proceni emisija saobraćajnog toka u Srbiji podrazumevala je upotrebu emisionih modela razvijenih za druga područja (gradove ili države) što omogućava samo relativno poređenje varijanti rešenja. Razvijeni metodološki pristup prikuplјanja i modeliranja je dobra osnova za formiranje modela specifičnog za lokalne uslove koji bi omogućio i apsolutnu kvantifikaciju emisije. Formiranjem konceptualnog modela odnosno metodologije formiranja modela, koji kao ulaz koristi samo podatke o načinu vožnje u svakoj sekundi, za konkretan slučaj matematički je opisana veza emisionog sa mikrosimulacionim transportnim modelom. Za primenu u makro i mezoskopskim modelima potrebno je generisati emisione faktore na nivou prosečnih brzina. Baza podataka na nivou svake sekunde je dobra osnova za generisanje emisionih faktora jer omogućava simuliranje bilo kog ciklusa vožnje. A generisanje emisionih faktora je zasnovano na ciklusima vožnje koji predstavlјaju karakteristično ponašanje vozača u određenim saobraćajnim okolnostima. Upotreba podataka o emisijama vozila na nivou sekunde je bila ograničena na istraživačku zajednicu zbog visoke cene uređaja za merenje. Formiranjem merne instalacije u ovoj disertaciji potvrđena je mogućnost formiranja ekonomične merne metodologije koja će omogućiti formiranje baze podataka o emisijama vozila u realnim uslovima u saobraćajnom toku kao osnova za precizno određivanje emisija vozila u saobraćajnom toku u urbanim područjima. Na taj način se omogućava pristup podacima širem krugu zainteresovanih strana i brži napredak u oblasti istraživanja. Pri formiranju merne instalacije, osnovni problem je bio rešavanje problema kvantifikovanja ukupne količine zagađujućih materija. Problem se svodi na mogućnost transformisanja jedinica u kojima se uobičajeno meri emisija (ppm ili mg / m 3) u apsolutnu količinu emitovanog gasa ( mg / s ). Problem je uspešno rešen upotrebom Pitove cevi za merenje brzine gasa koja predstavlјa sastavni deo merne instalacije. Rad je u osnovi multidisciplinaran. Ističe se ideja upotrebe teorije kontrole sistema u obradi baze podataka o emisijama. Na taj način se daje značajan prilog širenju mogućnosti u obradi prikuplјenih podataka za formiranje modela i mogućnostima budućih istraživanja koja se tiču varijabilnosti i pouzdanosti podataka.The u se of transport models in traffic flow emission estimation is an important part of sustainable transport planning in major urban areas. Impact assessment of the traffic solutions to the environment is one of the three basic components of sustainability. Previous experience in the emission estimations in Serbia show the use of emission models developed for other areas (cities or countries) which allow only relative comparison of variant solutions. Methodological approach of data collection and modelling developed in this Dissertation is a good basis for development of locally specific model that would allow the absolute quantification of emissions. The development of the conceptual model and the modelling methodology, which uses second - by - second driving pattern data as an only input, is mathematically described in conn ection with micro - simulation transport model. Emission factors based on average speed need to be generated for the use in macro and mesoscopic models. Database on a second - by - second basis enables estimation of emission factors for any driving cycle. Drivin g cycles represent typical human behaviour in certain traffic conditions. The use of second - by - second vehicle emission data was limited to the research community because of the high cost of measuring equipment. Measuring installations built in this thesis confirmed the possibility of creating cost - effective measurement methodology. Methodology will allow the establishment of a vehicle emissions database for real traffic conditions as a basis for accurate vehicle emission estimation in the traffic flows in u rban areas. It provides data for a wider range of stakeholders and the advance in this field of research. The main problem was establishing the total amount of emissions. The problem boils down to the possibility of unit’s conversion: turning ppm or mg/m3, usually used in emissions measurements, to absolute amount of gas emitted (mg/s). The problem has been successfully resolved using Pitot's tube to measure gas velocity, which is an integral part of the measuring installation. The work is essentially multi - disciplinary. The idea of using the system control theory in the processing of the emission data is emphasized. The approach contributes to expanding possibilities in emission data processing for modelling purposes. The possibilities for future resea rch related to the variability and reliability of the data are also expande

Levels of insulin, insulin-like growth factor-I and thyroid hormones in relation to the body condition score changes in periparturient dairy cows

The objective of this study was to determine the levels of insulin, insulin like growth factor I (IGF-I) and thyroid hormones in relation to the body condition score (BCS) of periparturient dairy cows. The study was carried out on twenty Holstein-Friesian dairy cows with average milk production of 7000 L/305 days in the previous lactation, parity ranging from 2-4. All cows were BCS scored during the early dry period, 7±3 days before and after parturition. Based on the BCS at the early dry period, cows were divided in two groups: cows with high BCS (3.75- 4.25, HBCS, n=10), and cows with moderate BCS (2.75-3.75, MBCS, n=10). Blood samples were taken at the time of BCS evaluation. Concentrations of insulin, IGF-I, triiodothyroinine (T3) and thyroxine (T4) were determined by radioimmunoassay (RIA, INEP-Zemun, Serbia). Statistical differences between mean values were determined using Student t-test (p<0.01). Mean BCS values at early dry period were significantly different compared to two other periods (p<0.01) within both groups, but BCS was similar in both groups at 7±3 days after calving (2.69±0.67:2.62± 0.27, p>0.05). IGF-I level in HBCS cows at days 7±3 before calving was significantly higher (16.28±3.07:11.76±2.28, p<0.01), with a reverse relationship after calving (3.77±1.64:8.46±2.37, p<0.01). Insulin level was significantly lower at 7±3 days before calving in HBCS cows (16.26±4.60:20.18±4.96mIU/L, p<0.05). Thyroid hormones levels were significantly lower in HBCS group et all examined periods. [Projekat Ministarstva nauke Republike Srbije, br. III 46002 i br. 31003

The comparison of gamma-radiation and electrical stress influences on oxide and interface defects in power VDMOSFET

The behaviour of oxide and interface defects in n-channel power vertical double-diffused metal-oxide-semiconductor field-effect transistors, firstly degraded by the gamma-irradiation and electric field and subsequently recovered and annealed, is presented. By analyzing the transfer characteristic shifts, the changes of threshold voltage and underlying changes of gate oxide and interface trap densities during the stress (recovery, annealing) of investigated devices, it is shown that these two types of stress influence differently on the gate oxide and the SiO2-Si interface. [Projekat Ministarstva nauke Republike Srbije, br. OI171026

On some fixed point theorems under (α,ψ,ϕ) -contractivity conditions in metric spaces endowed with transitive binary relations

After the appearance of Nieto and Rodríguez-López’s theorem, the branch of fixed point theory devoted to the setting of partially ordered metric spaces have attracted much attention in the last years, especially when coupled, tripled, quadrupled and, in general, multidimensional fixed points are studied. Almost all papers in this direction have been forced to present two results assuming two different hypotheses: the involved mapping should be continuous or the metric framework should be regular. Both conditions seem to be different in nature because one of them refers to the mapping and the other one is assumed on the ambient space. In this paper, we unify such different conditions in a unique one. By introducing the notion of continuity of a mapping from a metric space into itself depending on a function α, which is the case that covers the partially ordered setting, we extend some very recent theorems involving control functions that only must be lower/upper semi-continuous from the right. Finally, we use metric spaces endowed with transitive binary relations rather than partial orders.This article was funded by the Deanship of Scientific Research (DSR), King Abdulaziz University, Jeddah. N Shahzad acknowledges with thanks DSR for financial support. A-F Roldán-López-de-Hierro is grateful to the Department of Quantitative Methods for Economics and Business of the University of Granada. The same author has been partially supported by Junta de Andalucía by project FQM-268 of the Andalusian CICYE

Vehicle emission survey and modeling in the context of street network traffic flow modeling

Upotreba transportnih modela za procene emisija predstavlјa važan deo procesa održivog planiranja saobraćaja većih urbanih područja . Procena uticaja saobraćajnih rešenja na životnu sredinu je jedna od tri osnovne komponente održivosti. Prethodna praksa u proceni emisija saobraćajnog toka u Srbiji podrazumevala je upotrebu emisionih modela razvijenih za druga područja (gradove ili države) što omogućava samo relativno poređenje varijanti rešenja. Razvijeni metodološki pristup prikuplјanja i modeliranja je dobra osnova za formiranje modela specifičnog za lokalne uslove koji bi omogućio i apsolutnu kvantifikaciju emisije. Formiranjem konceptualnog modela odnosno metodologije formiranja modela, koji kao ulaz koristi samo podatke o načinu vožnje u svakoj sekundi, za konkretan slučaj matematički je opisana veza emisionog sa mikrosimulacionim transportnim modelom. Za primenu u makro i mezoskopskim modelima potrebno je generisati emisione faktore na nivou prosečnih brzina. Baza podataka na nivou svake sekunde je dobra osnova za generisanje emisionih faktora jer omogućava simuliranje bilo kog ciklusa vožnje. A generisanje emisionih faktora je zasnovano na ciklusima vožnje koji predstavlјaju karakteristično ponašanje vozača u određenim saobraćajnim okolnostima. Upotreba podataka o emisijama vozila na nivou sekunde je bila ograničena na istraživačku zajednicu zbog visoke cene uređaja za merenje. Formiranjem merne instalacije u ovoj disertaciji potvrđena je mogućnost formiranja ekonomične merne metodologije koja će omogućiti formiranje baze podataka o emisijama vozila u realnim uslovima u saobraćajnom toku kao osnova za precizno određivanje emisija vozila u saobraćajnom toku u urbanim područjima. Na taj način se omogućava pristup podacima širem krugu zainteresovanih strana i brži napredak u oblasti istraživanja. Pri formiranju merne instalacije, osnovni problem je bio rešavanje problema kvantifikovanja ukupne količine zagađujućih materija. Problem se svodi na mogućnost transformisanja jedinica u kojima se uobičajeno meri emisija (ppm ili mg / m 3) u apsolutnu količinu emitovanog gasa ( mg / s ). Problem je uspešno rešen upotrebom Pitove cevi za merenje brzine gasa koja predstavlјa sastavni deo merne instalacije. Rad je u osnovi multidisciplinaran. Ističe se ideja upotrebe teorije kontrole sistema u obradi baze podataka o emisijama. Na taj način se daje značajan prilog širenju mogućnosti u obradi prikuplјenih podataka za formiranje modela i mogućnostima budućih istraživanja koja se tiču varijabilnosti i pouzdanosti podataka.The u se of transport models in traffic flow emission estimation is an important part of sustainable transport planning in major urban areas. Impact assessment of the traffic solutions to the environment is one of the three basic components of sustainability. Previous experience in the emission estimations in Serbia show the use of emission models developed for other areas (cities or countries) which allow only relative comparison of variant solutions. Methodological approach of data collection and modelling developed in this Dissertation is a good basis for development of locally specific model that would allow the absolute quantification of emissions. The development of the conceptual model and the modelling methodology, which uses second - by - second driving pattern data as an only input, is mathematically described in conn ection with micro - simulation transport model. Emission factors based on average speed need to be generated for the use in macro and mesoscopic models. Database on a second - by - second basis enables estimation of emission factors for any driving cycle. Drivin g cycles represent typical human behaviour in certain traffic conditions. The use of second - by - second vehicle emission data was limited to the research community because of the high cost of measuring equipment. Measuring installations built in this thesis confirmed the possibility of creating cost - effective measurement methodology. Methodology will allow the establishment of a vehicle emissions database for real traffic conditions as a basis for accurate vehicle emission estimation in the traffic flows in u rban areas. It provides data for a wider range of stakeholders and the advance in this field of research. The main problem was establishing the total amount of emissions. The problem boils down to the possibility of unit’s conversion: turning ppm or mg/m3, usually used in emissions measurements, to absolute amount of gas emitted (mg/s). The problem has been successfully resolved using Pitot's tube to measure gas velocity, which is an integral part of the measuring installation. The work is essentially multi - disciplinary. The idea of using the system control theory in the processing of the emission data is emphasized. The approach contributes to expanding possibilities in emission data processing for modelling purposes. The possibilities for future resea rch related to the variability and reliability of the data are also expande

Application of transport demand modeling in pollution estimation of a street network

The importance of transportation modeling, especially personal car flow modeling, is well recognized in transportation planning. Modern software tools give the possibility of generating many development scenarios of transport system, which can be tested quickly. Transportation models represent a good (and necessary) basis in the procedure of environmental traffic impacts and energy emission estimation. Research in this paper deals with the possibility of using transportation modeling as a tool for estimation of some air pollution and global warming indicators on street network, produced by personal cars with internal combustion engines. These indicators could be the basis for defining planning and management solutions for transport system with respect to their environmental impacts. All the analyses are based on several years of research experience in Belgrade. According to the emissions of gases from the model, the values of other green house gases can be estimated using the known relations between the pollutants. There is a possibility that all these data can be used to calculate the transportation systems impact on temperature increase in urban areas

Analysis of sustainable urban mobility plans

Solving traffic problems, rather than in a conventional manner, i.e. through the construction of infrastructure and customization requirements, began to be implemented in a different way, by applying measures to motivate users to -use passenger car less, and that more of their daily activities are reached by nonmotorized modes of movement. Sustainable urban transport plans (SUP) were introduced in legislation of the EU, strategic documents that help create a better quality of life in cities. For the purposes of this study, a review of the literature related to existing plans of some major European cities was carried out, as well as small, focusing on cities of the surroundings. On this basis, the similarities and differences were ephasized in proposed measures to reach the goals of sustainable development of transportation systems. In conclusion recommendations are given on the possibility of use of experiences and applications in all the individual local communities

Fear of negative evaluation and social anxiety in the context of the revised reinforcement sensitivity theory

The main goal of this research paper is to examine the predictive power of personality traits in relation to fear of negative evaluation and social anxiety. The revised Reinforcement Sensitivity Theory (rRST) postulates the existence of three major personality systems - Behavioural Inhibition System (BIS), Behavioural Activation System (BAS), and Fight-Flight-Freeze System (FFFS). In order to assess the personality traits, the Reinforcement Sensitivity Questionnaire was used (RSQ). Fear of negative evaluation was assessed using the Fear of Negative Evaluation Scale - Brief form (FNE-B), while social anxiety evaluation was obtained by Social Anxiety Scale (SA2). The sample consisted of 222 psychology students engaged in 1st and 2nd year of studies at the University of Niš and the University of Novi Sad. In order to respond to the research questions, two separate multiple regression analyses were performed. In both analyses, personality traits were the predictors, while the differences were linked to the criteria variables - Model1 - fear of negative evaluation, and Model2 - social anxiety. Both models were statistically significant. According to the results, Fear of negative evaluation model explains a total of 41% of the criteria variance, while Social anxiety model explains 46% of the criteria variance. In both models, BIS stands out as the statistically significant and the best predictor. When comparing the results of both models, the differences relate to the second significant predictor. Namely, Fight response stands out in the first model, while Freeze response stands out in the second one. The obtained findings are discussed and interpreted in the context of rRST

Researching the weather impact on trip generation in European cities

Climate change and changes in weather conditions have the impact on the transport system. Changes in weather conditions cause changes in the transport supply, as well as in transport demand. The first researches about weather impact on transport demand in the cities were carried out at the end of the nineties and have been intensified in the last ten years. Most of the researches about weather impact on trip generation were carried out in the countries of Northern Europe. In recent years, researches are also conducted in European countries that have climate conditions and population habits significantly different from northern European countries. This paper presents an overview of the areas in which weather impact on the trip generation was investigated. The most important conclusions of the conducted research are presented and the weather components that have the greatest influence on the trip generation are indicated. Understanding the weather impact on the transport demand is necessary for the implementation of transportation planning procedures in the upcoming climate change conditions