Engineering

Instabilidade aerodinâmica por flutter em estruturas prismáticas de secção retangular
This paper is dedicated to the study of the occurrence of flutter instability in slender prismatic structures of rectangular cross section. A two degree of freedom model is considered and its non dimensional formulation is derived so that a minimum number of non dimensional parameters governing the occurrence of flutter instability are put in evidence. A very good agreement has been obtaine...


Respuesta dinámica de edificaciones producida por campos de ondas incidentes considerando la interacción suelo-estructura
This paper presents 2 methodologies based on the Boundary Element Method and the Finite Element Method to study soil-structure interaction effect on building behaviour. A 3-story building response induced by an incident wave field is studied using both methods. The results obtained show a good agreement. Then, a simplified model is validated from these methods and several buildings are analysed...
Seleção de topologias ótimas de estruturas elásticas 2D com restrição de tensão – via Smooth Evolutionary Structural Optimization
O artigo aborda a otimização topológica em problemas de elasticidade plana linear considerando a minimização do volume com restrição de tensão e empregando um índice de desempenho como monitoramento para o encontro da região de ótimo. Utiliza‐se para este fim o método clássico da otimização evolucionária estrutural, ou Evolutionary Structural optimization (ESO). Este procedime...


Modifying Glass Fibers with Graphene Oxide: Towards High-Performance Polymer Composites
Graphene oxide (GO) sheets were covalently grafted onto glass fibers (GFs) to improve the interfacial properties of GFs/polymer composites. It was confirmed that GO sheets were chemically grafted onto GFs via amido bond. The surface configuration of GFs changed by GO sheets could enhance strength and toughness of the interfacial region between GFs and polymer matrix. This strategy has the poten...
Quorum Sensing Activity of Hafnia alvei Isolated from Packed Food
Quorum sensing (QS) is a mechanism adopted by bacteria to regulate expression of genes according to population density. N-acylhomoserine lactones (AHLs) are a type of QS signalling molecules commonly found in Gram-negative bacteria which have been reported to play a role in microbial spoilage of foods and pathogenesis. In this study, we isolated an AHL-producing Hafnia alvei strain (FB1) from s...


Degradation of Phosphate Ester Hydraulic Fluid in Power Station Turbines Investigated by a Three-Magnet Unilateral Magnet Array
A three-magnet array unilateral NMR sensor with a homogeneous sensitive spot was employed for assessing aging of the turbine oils used in two different power stations. The Carr-Purcell-Meiboom-Gill (CPMG) sequence and Inversion Recovery-prepared CPMG were employed for measuring the 1H-NMR transverse and longitudinal relaxation times of turbine oils with different service status. Two signal comp...
Ozone Sensing Based on Palladium Decorated Carbon Nanotubes
Multiwall carbon nanotubes (MWCNTs) were easily and efficiently decorated with Pd nanoparticles through a vapor-phase impregnation-decomposition method starting from palladium acetylacetonates. The sensor device consisted on a film of sensitive material (MWCNTs-Pd) deposited by drop coating on platinum interdigitated electrodes on a SiO2 substrate. The sensor exhibited a resistance change to oz...

Heat transfer mechanism of the C/SiC ceramics pyramidal lattice composites
An innovative design of pyramidal lattice composites with high temperature C/SiC ceramics as constituent has been proposed for the purpose of thermal protection system design. A sample with dimensions of 230×130×20mm was firstly fabricated by interweaving and chemical vapor infiltration (CVI) method. Heat transfer mechanism of C/SiC lattice has been discovered to explore the optimal design of...
Mesomechanical originally: aspects of computational modeling for non-homogeneous materials joined by forming
The metal forming and joining industries are constantly evolving to adapt to new materials and alloys and to meet customers’ needs. However, the size of the companies in this segment is typically small. Therefore, the progress of the mesomechanical originally: modeling on non-homogeneous materials is relatively slow originally: . This article aims to contribute to the advancement of such comp...

Manipulating Mental States Through Physical Action
We present our implementation of a self-as-simulator architecture for mental state manipulation through physical action. The robot attempts to model how a human’s mental states are updated through their visual perception of the world around them. This modeling, combined with geometrically detailed, perspective correct simulations of the immediate future, allows the robot to choose actions whi...
A modified solution of radial subgrade modulus for a circular tunnel in elastic ground
In models based on Winkler springs for tunnel lining design, designers always face the difficulty of selecting appropriate values for the radial subgrade modulus (k r ). The widely used solution k r for a circular tunnel in elastic ground proposed by was found to be applicable only when the tunnel radial deformation is oval-shaped. On the basis of the Wood׳s solution, this note presents a g...

Integration of construction control and pile setup into load and resistance factor design of piles
Regionally developed Load and Resistance Factor Design (LRFD) recommendations for bridge pile designs are enhanced by integrating the construction control capability of dynamic analysis methods and the recently developed pile setup quantification method in the calibration process. Using a high quality, electronic Pile LOad Test (PILOT) database and 10 recently completed full-scale pile tests, r...
Study and application of a regenerative Stirling cogeneration device based on biomass combustion
Fuelling micro-combined heat and power (micro-CHP) devices using renewable sources, such as biogas, can enhance the energy and environmental benefits associated with such devices. This paper presents a solution for increasing the electric efficiency of biogas-fed Stirling co-generators by recuperating the energy content of the combustion flue gas. When economically and energetically convenient ...
The effect of selecting proper refrigeration cycle components on optimizing energy consumption of the household refrigerators
This paper presents experimental results of hot-wall condenser removal, condenser air cooling increment, capillary tube diameter effect, compressor cooling capacity effect, changes of R134a charge amount and ambient temperature effect on a commercial bottom mounted freezer to decrease energy consumption and production cost. Experiments were carried out on a 418 L dual evaporator domestic botto...
Study on the influence of airflow on the temperature of the surrounding rock in a cold region tunnel and its application to insulation layer design
To show the influence of airflow on the temperature of the surrounding rock in a cold region tunnel, a temperature field model was developed. The model includes temperature control equations of the surrounding rock, air temperature field control equations in the tunnel and wind flow control equations of the turbulence field. On this basis, a numerical analysis method is used to discuss the temp...