Search results for "31"
showing 10 items of 4401 documents
Todavía unas palabras sobre las venas cefálica y basílica
1993
Ever since 1879, when Josef Hyrtl first formulated his thesis that the names of the cephalic and basilic veins, as applied to the arm veins, were of Arab origin, a discussion began between philologists and historians of medicine as the former defended the Greek source of such denominations whilst the latter shared the view of the Viennese anatomist. The author, after making a critical review of the -relevant works published hitherto, unearthes a text drawn from a Persian manuscript dating back to the 15th century that, in his view, confirms the rigthness of the Viennese anatomist's thesis.
The role of sport-specific play and practice during childhood in the development of adolescent Finnish team sport athletes
2016
This study sought to understand the role of sport-specific play and practice in the development of adolescent team sport athletes in the Finnish sports development system. Participants were male, 15-year-old soccer (n = 141), ice hockey (n = 204), and basketball (n = 96) players, divided into three groups based on the amount of sport-specific play and practice experienced during childhood. Data were collected with sport-specific inventories of practice history, tactical skills, psychological skills, and sport-specific skill test. Results showed that athletes with more sport-specific play and practice during childhood had more sport-specific play and practice during adolescence, better techn…
The use of reflection-card by elite youth basketball players, head coach and team manager : effects on players’ performance and perceptions of users
2017
AbstractThe purpose of the present paper was to test the effectiveness of the r-cards in sport performance, and to examine what kind of benefits and challenges the head coach, team manager and female basketball players (N = 12) faced when using the r-cards. Mixed methods were employed to gather specific data to answer the research questions. Inferential statistical analyses were conducted to examine whether players’ performances in terms of their targeted defensive rebound percentage and free-throw percentage differed across the five matches played. No significant differences were found. However, evidence from the qualitative data provides a contrasting but insightful perspective. Subjectiv…
Experimental Evaluation of the Performance of a Three-Phase Five-Level Cascaded H-Bridge Inverter by Means FPGA-Based Control Board for Grid Connecte…
2018
Over the last decades, plants devoted to the generation of green energy significantly increased their number, together with the demand of same electrical energy, also stored in battery systems. This fact produced the growth of energy conversion systems with advanced performances with respect to the traditional ones. In this circumstance, multilevel converters play a significant role for their great advantages in performances, flexibility, fault-tolerability, employment of renewable energy sources and storage systems and finally yet importantly reduced filter requirements. In this context, this paper faces the performance of a cascaded H-bridge 5 level inverter in terms of harmonic distortio…
Battery Models for Battery Powered Applications: A Comparative Study
2020
Battery models have gained great importance in recent years, thanks to the increasingly massive penetration of electric vehicles in the transport market. Accurate battery models are needed to evaluate battery performances and design an efficient battery management system. Different modeling approaches are available in literature, each one with its own advantages and disadvantages. In general, more complex models give accurate results, at the cost of higher computational efforts and time-consuming and costly laboratory testing for parametrization. For these reasons, for early stage evaluation and design of battery management systems, models with simple parameter identification procedures are…
Recharge stations: A review
2016
Charging equipment for all-Electric Vehicles (EVs) is classified by the rate at which the batteries are charged. Charging times vary based on how depleted the battery is, how much energy it holds, the type of battery, and the type of Electric Vehicle Supply Equipment (EVSE). In this paper, a review of the innovative charging stations is reported.
Fuel cell modelling for power supply systems design
2008
Today academic and industrial research is addressed on fuel cell based power supply to replace current lithium-ion and similar rechargeable battery systems. For system simulation, fuel cell models are developed. Even if power electronics designers demand for a blackbox model to limit the knowledge of physical and chemical parameters, high performance in terms of model accuracy and portability is absolutely necessary. A steady state and dynamic fuel cell model oriented to power supply systems design is proposed and, as an example, the implementation on PSIM software is presented. Simulation and experimental results are compared and the model portability is discussed. ©2008 IEEE.
Wireless battery charging for electric bicycles
2017
The contactless solution is increasingly spreading as method of battery charging for Electric Vehicles (EVs). The standard technology of contactless EV battery charging is based on the Inductive Power Transfer (IPT) between two coupled coils, one connected to the electrical grid and the other one connected to the rechargeable battery. The IPT provides benefits in terms of safety and comfort, due to the absence of a plug-in operation. In this paper, an overview on the IPT applied to the battery charging of electric bicycles is provided, with some general considerations on the technical implications. Moreover, a prototype of contactless battery charging for E-bikes is proposed and described.
A 9-level three-phase multilevel converter with harmonic mitigation and integrated battery balancing
2019
In this paper, a 9 level three-phase multilevel converter with a harmonic mitigation control method and an integrated battery balancing algorithm for automotive purpose is proposed. Each level of the converter is composed by a buck-boost converter and an h-bridge in cascaded connection. The control algorithm is implemented to achieve the harmonic mitigation on the output voltage waveform and to maintain the battery input voltages balanced. The design and operation of the system is described, and simulation study is reported using Matlab/Simulink platform.
Experimental Investigation on Magnetic Field Effects of IPT for Electric Bikes
2018
The wireless power transmission (WPT) is increasingly representing a promising technology and an innovative solution, especially for the electric vehicles (EVs) battery charging. The inductive power transfer (IPT) is the standard technology of wireless charging: the energy transfer occurs between two magnetically coupled coils. The IPT-based battery charging is especially convenient for E-bikes and the physiological effects related to the generated magnetic fields should be estimated. In this context, this work presents a 200Â W prototype of wireless battery charger for E-bikes. In addition, the measurements regarding the surrounding magnetic field are given in detail in order to evaluate t…