scholarly journals Comparative analysis of the hybrid power system topology for a high efficiency prototype vehicle

2021 ◽  
Vol 2130 (1) ◽  
pp. 012032
Author(s):  
S Szewc ◽  
A Miękina ◽  
T Brzyszko ◽  
J Czarnigowski ◽  
W Górski ◽  
...  

Abstract The paper presents a comparative analysis of three solutions of the power supply topology of a high-efficiency hybrid vehicle. The analysis was carried out for the Hydros prototype vehicle developed at the Lublin University of Technology for the Shell Eco Marathon competition. This vehicle is driven by an electric motor powered by two energy sources: hydrogen fuel cells and supercapacitors, allowing temporary energy buffering. Three variants of the mutual connection of the two energy sources to a single receiver were analysed, taking into account the voltage converter systems between the individual components of the system. The aim of these analyses was to determine the most energy-efficient solution.

Author(s):  
Елена Лактюхина ◽  
Elena Laktyukhina ◽  
Георгий Антонов ◽  
Georgy Antonov

The article presents a comparative analysis of marital and family mindsets of two categories of the demographically active population of modern Russia: (1) individuals that have no experience of a divorce and (2) those who have already experienced one or more official termination of a marriage. The empirical base of the analysis is the data of the author’s questionnaire survey conducted by representative sampling in Volgograd and Volgograd Region in 2015–2016. The analysis was made on the following basic empiric indicators: optimal (from the viewpoint of the respondents) age for the first marriage, frequency of mentioning marital and family statuses as the respondents describe their own social and demographic “portrait”, legitimate causes of a divorce and a number of others. It is found that, in the case of sufficiently strong traditional marital and family mindsets, perception of marital norms is adjusted, if an “abnormal” event (such as a divorce) occurs in the individual’s life course. At the same time, perception of the marriage stability is less variable and does not depend on the social and demographic characteristics of the respondents, including the presence/absence of a marriage termination experience. The “strongest” factor that affects the change of the marital and family mindsets is age. With age (and, consequently, experience accumulation), importance of the majority of main factors capable of preventing the individual from a divorce decreases and, therefore, the risk of such event increases.


Electronics ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 188
Author(s):  
Žiga Korošak ◽  
Nejc Suhadolnik ◽  
Anton Pleteršek

The aim of this work is to tackle the problem of modulation wave shaping in the field of near field communication (NFC) radio frequency identification (RFID). For this purpose, a high-efficiency transmitter circuit was developed to comply with the strict requirements of the newest EMVCo and NFC Forum specifications for pulse shapes. The proposed circuit uses an outphasing modulator that is based on a digital-to-time converter (DTC). The DTC based outphasing modulator supports amplitude shift keying (ASK) modulation, operates at four times the 13.56 MHz carrier frequency and is made fully differential in order to remove the parasitic phase modulation components. The accompanying transmitter logic includes lookup tables with programmable modulation pulse wave shapes. The modulator solution uses a 64-cell tapped current controlled fully differential delay locked loop (DLL), which produces a 360° delay at 54.24 MHz, and a glitch-free multiplexor to select the individual taps. The outphased output from the modulator is mixed to create an RF pulse width modulated (PWM) output, which drives the antenna. Additionally, this implementation is fully compatible with D-class amplifiers enabling high efficiency. A test circuit of the proposed differential multi-standard reader’s transmitter was simulated in 40 nm CMOS technology. Stricter pulse shape requirements were easily satisfied, while achieving an output linearity of 0.2 bits and maximum power consumption under 7.5 mW.


Symmetry ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1325
Author(s):  
Zhongwei Gao ◽  
Changqing Pan ◽  
Chang-Ho Choi ◽  
Chih-Hung Chang

Water pollution is a growing global issue; there are many approaches to treating wastewater, including chemical coagulation, physical adsorption, and chemical oxidation. The photocatalysis process has provided a solution for removing pollutants from wastewater, where the pair of the photoelectron and hole works through an asymmetric way to degrade the contaminants under UV irradiation. This method offers an alternative route for treating the pollutant with a lower energy cost, high efficiency, and fewer byproducts. A continuous-flow microfluidic reactor has a channel size from tens to thousands of micrometers, providing uniform irradiation and short diffusion length. It can enhance the conversion efficiency of photocatalysis due to the simple spatial symmetry inside the microreactor channel and among the individual channels. In addition, the bandgap of TiO2, ZnO, or other photocatalyst nanoparticles with symmetric crystal structure can be modified through doping or embedding. In this mini-review, a review of the reported continuous-flow photocatalytic microfluidic reactor is discussed from the perspective of both microreactor design and material engineering.


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