China
Africa
Explore chapters and articles related to this topic
Internal Structures and Operating Principles of Linux Real-Time Extensions
Published in Ivan Cibrario Bertolotti, Gabriele Manduchi, Real-Time Embedded Systems, 2017
Ivan Cibrario Bertolotti, Gabriele Manduchi
Letting real-time Xenomai threads work in user space and use Linux system calls simplify the development of real-time applications, and, above all, allows an easy porting of existing applications from other systems. To this purpose, the Xenomai API provides several sets of synchronization primitives, called skins, each emulating the set of system routines of a given operating system.
Low velocity impact response and influence of parameters to improve the damage resistance of composite structures/materials: a critical review
Published in International Journal of Crashworthiness, 2022
Kiran Kaware, Mangesh Kotambkar
Abdullah Akatay et al. [109] studied the repeatedly impacted LVI behaviour of sandwich structures made up of glass fibre reinforced epoxy composite face-sheets and aluminium honeycomb core. damage resistance and repeated impact performance evaluated by determining the deflection, maximum load, and impact energies of honeycomb sandwich structures. With the help of Force time histories, the delamination threshold and damage modes are determined. Also, residual compressive properties of single and repeated impacted sandwich structures were studied by using CAI tests. Bin Yang et al. [85] performed LVI and CAI on foam-filled sandwich panels with a hybrid facesheet to analyze the failure modes. SEM is used to study the microstructure of the impacted specimens. Results show pure carbon facesheet shows poor resistance to impact than pure glass facesheet in LVI test. Buckling of skin and foam and facesheet wrinkling are two main damage modes in CAI test. Brenda L. Buitrago et al. [18] performed a numerical and experimental impact test on a sandwich structure to study perforation. Aluminium honeycomb core with carbon epoxy skins modelled in ABAQUS/Explicit software. Results compared shows good agreement with the difference of 2% for the ballistic limit. For skin, fibre breakage and in core plastic deformation are typically seen. G B Chai and S Zhu [110] reviewed the low velocity impact on sandwich structures.
Free vibration analyses of composite sandwich cylindrical shells with grid cores: experimental study and numerical simulation
Published in Mechanics Based Design of Structures and Machines, 2022
Davoud Shahgholian-Ghahfarokhi, Gholamhossein Rahimi, Mehdi Zarei, Hamzeh Salehipour
The main objective of the present article is an experimental and numerical investigation of the free vibrational behavior of composite sandwich cylindrical shells with grid cores. Firstly, specimens are fabricated from continuous glass fiber using a specially designed filament winding setup, and new mold. A 3D finite element model is also built using ABAQUS software which takes into consideration the exact geometric configuration of the stiffeners, outer and inner skins. In order to validate the accuracy of the numerical approaches, experimental modal analysis is performed to calculate the natural frequency and modal shapes. After that numerical approach is validated, different grid cores are being investigated, and the best grid cores are selected. Furthermore, a parametric study of the free vibration analysis of composite sandwich cylindrical shells with grid cores is performed. The influence of changes in the ribs’ number, rib thickness, outer and inner skin thicknesses, boundary condition and the fiber angle of the skin on the vibration frequencies of composite sandwich cylindrical shells with grid cores are studied. Finally, sandwich cylindrical shells are compared with un-stiffened and stiffened shells regarding efficiency.
Design-to-fabrication with thermo-responsive shape memory polymer applications for building skins
Published in Architectural Science Review, 2021
When the SMP prototypes for adaptive shading devices in building skins were aimed for investigation and validation initially, it was the biggest challenge to determine the computer design strategy through the setting of the variables and rules, and to physically convert the characteristics of the material through computer software, verifying its effectiveness and ensuring quantitative energy efficiency as well as qualitative aesthetic performance. But as the design-to-fabrication experimentation goes further, it is considered that the strength of this research is hands-on proof-of-concept models of various shapes and mechanisms through rapid manufacturing.