Search results for "efficiency"
showing 10 items of 1430 documents
Collaborative Content Downloading in VANETs with Fuzzy Comprehensive Evaluation
2019
Vehicle collaborative content downloading has become a hotspot in current vehicular ad-hoc network (VANET) research. However, in reality, the highly dynamic nature of VANET makes users lose resources easily, and the transmission of invalid segment data also wastes valuable bandwidth and storage of the users&rsquo
Modeling and Performance Analysis of Energy Efficiency Binary Power Control in MIMO-OFDM Wireless Communication Systems
2011
Published version of an article in the journal:International Journal of Distributed Sensor Networks. Also available from Hindawi Publishing: http://dx.doi.org/10.1155/2011/946258 The energy efficiency optimization of the binary power control scheme for MIMO-OFDM wireless communication systems is formulated, and then a global optimization solution of power allocation is derived. Furthermore, a new energy efficiency binary power control (EEBPC) algorithm is designed to improve the energy efficiency of MIMO-OFDM wireless communication systems. Simulation results show that the EEBPC algorithm has better energy efficiency and spectrum efficiency than the average power control algorithm in MIMO-O…
Wildfire Monitoring Based on Energy Efficient Clustering Approach for FANETS
2022
Forest fires are a significant threat to the ecological system’s stability. Several attempts have been made to detect forest fires using a variety of approaches, including optical fire sensors, and satellite-based technologies, all of which have been unsuccessful. In today’s world, research on flying ad hoc networks (FANETs) is a thriving field and can be used successfully. This paper describes a unique clustering approach that identifies the presence of a fire zone in a forest and transfers all sensed data to a base station as soon as feasible via wireless communication. The fire department takes the required steps to prevent the spread of the fire. It is proposed in this study…
Participation and compensation claims in voluntary forest conservation: A case of privately owned forests in Finland
2009
Abstract A new market-based voluntary programme aimed at preserving forest habitats on private land has been implemented in Finland. This scheme is based on conservation by fixed-term agreements between forest owners and a governmental authority. In this study we examine the characteristics of forest owners and their properties that indicate the owners' willingness to participate in the programme. In addition, we analyse factors affecting the real compensation claims. The study uses a dual set of data from the pilot project, i.e. one data set supplied by the authority and another collected from the owners involved in the project. The results suggest that to increase the participation rate, …
The residence permit for third-country nationals who are victims of human trafficking: A double-face instrument between compliance strategy and prote…
2017
Purpose The aim of the present study is to explore institutional design strategies that promote compliance by regulating peculiar sorts of agents, namely, human trafficking victims, starting from the point of view that institutions assume addressee virtue, but instead should consider the hypothesis of non-compliance or that the measures adopted reveal their inefficiency to satisfy the goals they were thought for, or that they are applied to obtain scopes, which are different from the ones they were conceived for. Design/methodology/approach Different methodological approaches, both deductive and inductive, are combined in the present paper, together with comparative and philosophical insig…
Influence d'une supplémentation en vitamines sur le rendement de la locomotion après une épreuve d'ultratrail
2006
International audience; Aim: The purpose of this study was to study changes in gross efficiency of locomotion after a prolonged trail running race (3000 m up and 300 m down). The second purpose was to investigate the effectiveness of supplementation in vitamin on gross efficiency variability.Materials and methods: Twenty-two well-trained endurance runners took part in this study. They had to perform four sub maximal tests before, 24, 48 and 72 hours after the race in order to estimate gross efficiency of locomotion and a maximal contraction test in the same period. They were divided in two groups either with supplementation (Isoxan Endurance ®) or without (placebo).Results: In both groups w…
Power Losses Minimization for Optimal Operating Maps in Power-Split HEVs: A Case Study on the Chevrolet Volt
2021
The power-split architecture is the most promising hybrid electric powertrain. However, a real advantage in energy saving while maintaining high performance can be achieved only by the implementation of a proper energy management strategy. This requires an optimized functional design before and a comprehensive analysis of the powertrain losses after, which could be rather challenging owing to the constructive complexity of the power-split transmission, especially for multi-mode architecture with multiple planetary gearing. This difficulty was overcome by a dimensionless model, already available in the literature, that enables the analysis of any power-split transmission, even in full electr…
Numerical and experimental study of hydrostatic displacement machine
2012
This paper presents a simulation tool to determine the structural deflections and corresponding leakage flow in a hydrostatic displacement motor. The simulation tool is applied to a new motor principle that is categorized as an extreme low-speed high-torque motor with dimensions that calls for attention to the volumetric efficiency. To counteract structural deflections the motor is equipped with compensation pressure volumes that may be used to limit the leakage flow across the end faces of the circular rotor. This leakage flow is investigated by solving Reynolds equation for the pressure distribution across both end faces. The fluid pressure is combined with structural calculations in a fl…
Performance and combustion analysis of a supercharged double-fuel spark ignition engine
2019
In order to increase fuel economy and reduce pollutant emissions in the last decades light duty spark ignition (SI) engines have become smaller, supercharged and equipped with direct injection. A suitable alternative to oil derived fuel is represented by gaseous fuels, such as Natural Gas (NG) and Liquefied Petroleum Gas (LPG), whose higher knock resistance and better mixing capabilities substantially improve vehicle fuel economy and pollutant emissions. The simultaneous combustion of gasoline and gaseous fuel (Double-Fuel operation, DF) in a naturally aspirated SI engine has already been investigated in the past also by the same authors, proving remarkable results in terms of engine effici…
Calibration of a knock prediction model for the combustion of a gasoline-natural gas mixture
2009
Gaseous fuels, such as Liquefied Petroleum Gas (LPG) and Natural Gas (NG), thank to their good mixing capabilities, allow complete and cleaner combustion than normal gasoline, resulting in lower pollutant emissions and particulate matter. Moreover natural gas, which is mainly constituted by methane, whose molecule has the highest hydrogen/carbon ratio, leads also to lower ozone depleting emissions. The authors in a previous work (1) experienced the simultaneous combustion of gasoline and natural gas in a bi-fuel S.I. engine, exploiting so the high knock resistance of methane to run the engine with an ‘overall stoichiometric’ mixture (thus lowering fuel consumption and emissions) and better …