Filter Results
3427299 results
Post-treatment methods enhance the fatigue strength of welded high-strength steel joints significantly. In industrial applications, one commonly applied technique is the high frequency mechanical impact (HFMI) treatment. Attained local benefits increasing fatigue strength are the compressive residual stress state, the reduced notch effect at the weld toe, and additionally the local work hardening of the material. This paper presents the set-up of a closed simulation loop including structural weld simulation, numerical computation of the HFMI-process, and a numerical evaluation of the local fatigue life.
Data Types:
  • Image
  • Tabular Data
This paper addresses an optimal model reference adaptive system (MRAS) to design power system stabilizer (PSS) in multi-machine electric power systems. Weighting factors of the proposed MRAS are adjusted by particle swarm optimization (PSO) as well as its input signal is limited by a normalization technique to assure network stability. The proposed modified-optimal MRAS-PSS is evaluated against conventional PSS to demonstrate its advantages. In order to investigate the performance of the proposed MRAS-PSS under parametric uncertainties, three operating conditions are defined and simulated. Several nonlinear and time-domain simulations are carried out to validate the viability and effectiveness of the proposed MRAS-PSS under network uncertainties.
Data Types:
  • Image
  • Tabular Data
Developing strategies for the water sector in integrated manner is essential. The present study details the development and uses of the Water Poverty Index (WPI) to be applied as a holistic tool for the conceptualization of water strategies in Egypt. The WPI herein considers the following: (i) water availability; (ii) access to water taking into account energy as a factor to water system operation; (iii) capacity to manage the water system considering the gender perspective; (iv) allocation of water uses considering the economic value of water; and (v) quality of the environment. The developed WPI was applied at the Egyptian governorates level and priorities to be achieved in their water sector were determined. The study concluded that, WPI as a summarized index combines into a single number a cluster of data is considered a robust tool to assist decision makers in determining priority to conduct prospect development plans in the water sector.
Data Types:
  • Image
  • Tabular Data
Data Types:
  • Tabular Data
La alteración de la marcha es frecuente en la esclerosis múltiple (EM) y tiene un gran impacto negativo en los pacientes pues conlleva a la pérdida progresiva de autonomía personal y social, y de productividad laboral. Esta guía pretende establecer recomendaciones para la evaluación del deterioro de la marcha y el uso de fampridina de liberación prolongada (fampridina-LP) como tratamiento de pacientes con EM y deterioro de la marcha en España.
Data Types:
  • Image
  • Tabular Data
La mHealth, definida como la prestación de información o asistencia sanitaria a través del uso de dispositivos móviles o tabletas, se postula como una de las grandes apuestas para pacientes, proveedores e inversores. Una app es un programa, con unas características especiales, que se instala en un dispositivo móvil, ya sea tableta digital o teléfono inteligente, y que suele tener un tamaño reducido, y cuyo objetivo es facilitar la consecución de una tarea determinada o asistir en gestiones diarias, siendo el modo de interacción entre el usuario y la aplicación el tacto.
Data Types:
  • Image
  • Tabular Data
Pattern recognition of Acoustic Emission (AE) data is generally performed based on prior knowledge about the acoustic signatures of material damage mechanisms. Traditionally, these signatures are implicitly assumed to be unaffected by damage accumulation during the fatigue life of the material. This study investigates the influence of cumulated damage under cyclic loading on the acoustic signatures of local fracture mechanisms in composites. Artificial AE sources are created using an ultrasonic transmitter and a Pencil Lead Break in order to reproduce various real-like AEs, such that the waveforms, measured at the sensor level, are characterized as similar to real acoustic signatures of local fractures in carbon/epoxy composites. It is shown that these waveforms are distorted with damage accumulation in both time and frequency domains, leading to important changes in the AE-features used in data classification. Consequently, this can engender unreliable statistical representation of the AE sources in such non-stationary media.
Data Types:
  • Image
  • Tabular Data
The information communication technology (ICT) outsourcing market is growing larger every year from the increasing number of companies that utilize ICT outsourcing, as industry scale increases and industrial specialization intensifies. However, the current circumstance is that security accidents related to ICT outsourcing are continuously occurring at an increasing scale. There is a lack of studies measuring the level of security management of organizational ICT outsourcing, which is the first step in performing security management of ICT outsourcing. In addition, most studies focus on general organizational security management. Accordingly, this paper aimed to design a model to measure the level of security management of companies utilizing ICT outsourcing. Specifically, this paper analyzed security vulnerabilities that could occur in ICT outsourcing that may be mapped with the accorded security measures as solutions to deduce items for ICT outsourcing security inspections. Next, this paper developed an ICT outsourcing security level quantification model by verifying the validity of the security inspection items deduced and by estimating item-specific weighted points. Additionally, the applicability of the ICT outsourcing security level quantification model developed was verified by applying it to actual companies.
Data Types:
  • Image
  • Tabular Data
To investigate Holocene vegetation and fire-disturbance histories in the treeline ecotone, macroscopic charcoal, plant-macrofossil, and pollen records from two lacustrine sediment records were used. Lake Lia is on the southern slope and Lake Brazi is on the northern slope of the west-east-oriented Retezat Mountain range in the Romanian Carpathians. The records were used to reconstruct Holocene fire-return intervals (FRIs) and biomass burning changes. Biomass burning was highest at both study sites during the drier and warmer early Holocene, suggesting that climate largely controlled fire occurrence. Fuel load also influenced the fire regime as shown by the rapid biomass-burning changes in relation to timberline shifts. Overall, the number of inferred fire episodes was smaller on the northern than on the southern slope. FRIs were also comparatively longer (1000–4000 years) on the northern slope where Picea abies-dominated woodlands persisted around Lake Brazi throughout the Holocene. On the southern slope, where Pinus mugo was more abundant around Lake Lia, FRIs were significantly shorter (80–1650 years). A period of frequent fire episodes occurred around 1900–1300 cal yr BP on the southern slope, when chironomid-inferred summer temperatures increased and the pollen record documents increased anthropogenic activity near the treeline. However, the forest clearance by burning to increase grazing land was subdued in comparison to other European regions.
Data Types:
  • Image
  • Document
Neurofeedback (NFB) allows subjects to learn self-regulation of neuronal brain activation based on information about the ongoing activation. The implementation of real-time functional magnetic resonance imaging (rt-fMRI) for NFB training now facilitates the investigation into underlying processes.
Data Types:
  • Image
  • Tabular Data
3