Search results for "design."
showing 10 items of 5715 documents
Multi-Resource Management for Multi-Tier Space Information Networks: A Cooperative Game
2019
With the drastic increase of space information network (SIN) traffic and the diversity of network traffic types, the optimal allocation of the scarce network resources is of great significance for optimizing the SIN system capability. In this paper, we propose a multi-resource management method for multi-tier SIN using the cooperative Nash bargaining solution. Since the original problem is a non-convex problem, we firstly make logarithmic transition, and then find a tightest lower bound function to convert the initial problem into a convex one. In order to carry out the optimal bandwidth and power allocation in SIN, we construct a joint bandwidth and power allocation (JBPA) algorithm. Simul…
Violencia escolar: derechos y deberes para la convivencia / SCHOOL VIOLENCE: RIGHTS AND DUTIES FOR COEXISTENCE
2017
Experts speak of violence as a psychosocial disease generated in violent environments habituation caused by a lack of democratic consciousness. In this regard, violence is broached in this paper considering it as some kind of atmosphere, especially when it is spread in school. Our contribution includes this perspective and concludes, after analysing the broad outlines of some programs and anti-harassment guidelines, the solution relates to promote social harmony and it goes through a basic premise: both aggressors and assaulted must be aware of their duties and basic rights.
Beyond Clicks and Beeps: In Pursuit of an Effective Sound Design Methodology
2007
Designing effective non-speech audio elements for a user-interface is a challenging task due to the complex nature of sounds and the changing contexts of non-visual interfaces. In this paper we present a design method, which is intended to take into account the complexity of audio design as well as the existing audio environment and the functional context of use. Central to this method is a rich use scenario, presented in the form of a radio play, which is used as a basis for the work of design panels. A previous version of the design method is analysed and specific practical issues are identified. Solutions to these issues are presented in the form of a modified version of the method. In t…
Identity and Cultural Transition: Lessons to Learn from a Negative Case Analysis
2020
In this paper, we present a single case study of identity crisis that unfolded in the cultural transition context. Our participant was ‘Jenni’ – a 26 years old female basketball player with the dou...
Autonomous Operation of Stationary Battery Energy Storage Systems—Optimal Storage Design and Economic Potential
2021
Global warming requires a changeover from fossil fuel based to renewable energy sources on the electrical supply side and electrification of the demand side. Due to the transient nature of renewables and fluctuating demand, buffer capacities are necessary to compensate for supply/demand imbalances. Battery energy storage systems are promising. However, the initial costs are high. Repurposing electric vehicle batteries can reduce initial costs. Further, storage design optimization could significantly improve costs. Therefore, a battery control algorithm was developed, and a simulation study was performed to identify the optimal storage design and its economic potential. The algorithm used is…
Wireless battery chargers for portable applications: Design and test of a high-efficiency power receiver
2013
In this study, the authors present a 5 W wireless battery charger for handheld devices. Efficiency-related issues are addressed. A power receiver architecture which improves power conversion efficiency is proposed. Design hints are provided for further applications. Comparison with a conventional architecture is provided as well. Laboratory prototypes of both the proposed and the conventional architectures have been realised. Both prototypes are tested by using the same power transmitter to perform a valuable comparison. As shown by the experimental results, in the receiver side power conversion efficiency is increased up to 99% thanks to the proposed solution.
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.
Analysis of a Fast Reserve Unit Behaviour with Additional Modular Synthetic Inertia Control
2021
The paper presents the results of a theoretical study on the behaviour of a battery storage system operated as a Fast Reserve Unit and equipped with additional synthetic inertia control. The Fast Reserve Unit is assumed connected to the transmission system of Sicily, operated as an isolated grid in order to show more clearly the effect of the Fast Reserve Unit intervention during a power imbalance. The unit is controlled also to provide synthetic inertia with a conventional control scheme and with a new scheme proposed by the authors and named “Modular Synthetic Inertia”. The latter has been conceived for offering a modular response as a function of the Rate of Change of Frequency, to avoid…
Optimization of urban delivery systems based on electric assisted cargo bikes with modular battery size, taking into account the service requirements…
2021
The implementation of new forms of urban mobility is a fundamental challenge for improving the performance of city logistic systems in terms of efficiency and sustainability. For such purposes, the exploitation of electric vehicles is currently being investigated as an alternative to traditional internal combustion engines. In particular, the employment of lightweight electric cargo bikes is seen as an attractive possibility for designing improved city distribution systems. Such vehicles, however, present substantial limitations related to their endurance, speed, power, and recharging times; therefore, their configuration must be optimized considering the actual operational context and the …
Control subsystem design for wireless power transfer
2014
Recently, the wireless power transfer has been increasingly employed. Particularly for the electric vehicles, the wireless solution is attractive for contactless battery charging, based on the Inductive Power Transfer (IPT). In this paper, a 150W prototype for IPT-based battery charging is presented and design criteria are reported. In addition to the power stage analysis, a proper control strategy is proposed. Simulation and experimental results are shown. The proposed control method aims at regulating the load current against variations in the magnetic coupling, so that the required amount of power can be supplied despite of unexpected decreases in the coupling efficiency.