Search results for "Efficient"

Ultrasonic guided wave propagation in long bones with varying cortical thickness

2009

The propagation of ultrasonic guided wave (GW) in the long bone is very sensitive to the bones' shapes, properties and cortical thicknesses (CTh). Most of the previous studies on the GW propagation in long bones mainly focused on the bones with uniform CTh. However, it is necessary to understand the impacts of CTh variation, such as mode conversion. Therefore, an adequate analysis on GW propagating in long bones with varying CTh is essential for the precise calibration of the quantitative measurement of it. The aim of this study is to use a modified boundary element method (BEM) to analyze the GW propagation characteristics in long bones with varying CTh. Numerical analysis implemented by t…

Mathematical modeling of a vehicle crash test based on elasto-plastic unloading scenarios of spring-mass models

2011

Published version of an article in the journal: The International Journal of Advanced Manufacturing Technology. Also available from the publisher on SpringerLink: htp://dx.doi.org/10.1007/s00170-010-3056-x This paper investigates the usability of spring which exhibit nonlinear force-deflection characteristic in the area of mathematical modeling of vehicle crash. We present a method which allows us to obtain parameters of the spring-mass model basing on the full-scale experimental data analysis. Since vehicle collision is a dynamic event, it involves such phenomena as rebound and energy dissipation. Three different spring unloading scenarios (elastic, plastic, and elasto-plastic) are covered…

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…

Statistical Analysis of the (In)efficiency of Bitcoin : A comparison of the weak form efficient market hypothesis in the US and Venezuela

2019

Master's thesis Business Administration BE501 - University of Agder 2019 Bitcoin is a phenomenon that has received a lot of attentionduringthe last years. Although the literature on the subject has expanded, there is still need for more research. This paper replicates the work of Urquhart (2016) and examines whether there isevidence ofweak form efficiency in the Bitcoin market. He found that the Bitcoin market in the US showed signs of moving towards weak form efficiency. We contribute to the existing literature by adding recentdata and comparing two different markets;the USand Venezuela. To obtain robustness of the results, the analysis is conducted by performing six different statistical …

Comparing indoor performances of a building equipped with four different roof configurations in 65 Italian sites

2020

Abstract—Despite the increasing concern of institutions and technical organizations toward the improvement of the building energy (and, therefore, environmental) efficiency, the main goal of technicians should be also devoted toward the levels of internal thermal comfort that buildings are able to realize. As that, the relationships between energy performances and comfort conditions provided by the enclosures are of paramount importance in guiding designers in their work. In this paper, the influence of diverse roof construction typologies on energy and indoor performance of buildings has been investigated, in different Italian sites during heating and cooling seasons. In addition, it must …

BEGIN: Big Data Enabled Energy-Efficient Vehicular Edge Computing

2018

Vehicular edge computing is essential to support future emerging multimedia-rich and delay-sensitive applications in vehicular networks. However, the massive deployment of edge computing infrastructures induces new problems including energy consumption and carbon pollution. This motivates us to develop BEGIN (Big data enabled EnerGy-efficient vehIcular edge computiNg), a programmable, scalable, and flexible framework for integrating big data analytics with vehicular edge computing. In this article, we first present a comprehensive literature review. Then the overall design principle of BEGIN is described with an emphasis on computing domain and data domain convergence. In the next section, …

Energy-Efficient Edge Computing Service Provisioning for Vehicular Networks: A Consensus ADMM Approach

2019

In vehicular networks, in-vehicle user equipment (UE) with limited battery capacity can achieve opportunistic energy saving by offloading energy-hungry workloads to vehicular edge computing nodes via vehicle-to-infrastructure links. However, how to determine the optimal portion of workload to be offloaded based on the dynamic states of energy consumption and latency in local computing, data transmission, workload execution and handover, is still an open issue. In this paper, we study the energy-efficient workload offloading problem and propose a low-complexity distributed solution based on consensus alternating direction method of multipliers. By incorporating a set of local variables for e…

Negatively cooperative binding of melittin to neutral phospholipid vesicles

2007

Abstract The association of basic amphipathic peptides to neutral phospholipid membranes is investigated in terms of binding and partition models. The binding of native and modified melittin to egg-yolk phosphatidylcholine vesicles is studied by steady-state fluorescence spectroscopy. The effect of the ionic strength shows an enhancement of the association as the ionic strength increases. After correction for electrostatic effects by the Gouy–Chapman theory, the melittin binding isotherms could be described by a partition model. In terms of conventional binding mechanisms, which do not take into account electrostatic effects, this would correspond to a negative cooperativity. A plausible wa…

Balancing of multi-stage pump using the coupling hub

2019

In this paper, we present an investigation to perform a temporary on-site balancing of machines which rotor is not accessible, such as multi-stage oil centrifugal pumps, in order to bring back the vibration magnitude below the alarm threshold, waiting for the scheduled general review of the machine. We have shown that if the vibration measured on the Driver End Support (DE) is very higher than that measured on the Non Driver End Support (NDE), we can consider the Coupling Hub fitted to the Pump (CHP) a correction plane in order to apply on site balancing by means of the Influence Coefficients Method. This permits to overcome the problem of the inaccessibility of the rotor and to solve, in t…

1993

In a new theoretical approach the separation of a pair of chain molecules (measured thermodynamically by the second osmotic virial coefficient A2) is treated as a two-step process: In the first step the molecules are detached from each other by the addition of solvent—keeping their dimensions constant—and in the second step the now isolated coils are allowed to relax into their equilibrium dimensions. For the description of the second step, in which only segments belonging to one molecule take part, an intra-molecular interaction parameter is introduced on the basis of the intrinsic viscosity. The present two-parameter approach yields A2 = A + σ M−(1−a) for the dependence of A2 on the molec…