Influence of geotextile arrangement on seismic performance of mid-rise buildings subjected to MCE shaking

Geotextile layers make it possible to construct mid-rise buildings sitting on shallow foundations in unfavourable soil conditions; this study investigates how the arrangement of geotextiles affects the seismic performance of mid-rise buildings under Maximum Considered Earthquake (MCE) shaking. The geotextile arrangement considered here includes the stiffness (5000?kN/m – 12000?kN/m), the length with respect to width of the foundation (B) (1B – 4B), the number of geotextile layers (1 – 7 layers), and their spacing (250?mm – 1000?mm). FLAC3D is used for the numerical simulation and to carry out nonlinear dynamic analysis in the time domain, and an inelastic constitutive model is used to simulate the behaviour of the structure and the geotextile layers under seismic loads. Variations in the shear modulus of soil and the corresponding damping ratio with cyclic shear strain are considered using a hysteretic damping algorithm to model the reasonable dissipation of energy in the soil. The interface between the foundation and ground surface, including the material and geometrical nonlinearities, are used to capture any possible slide and uplift in the foundations. The results are presented with regard to the geotextile arrangement considered, and include the tensile force mobilised in the geotextile layers, the response spectra at the bedrock and ground surface, the shear force developed in the structure, the maximum rocking angle of the foundation, permanent foundation settlement, maximum lateral displacement and the maximum and residual inter-storey drifts. The results show that the geotextile layers close to the edges of the foundation sustained most of the stress induced by foundation rocking, and the geotextile arrangement has a significant influence on the seismic response of mid-rise buildings. Thus, to satisfy the seismic performance of buildings and to optimise the design of foundations reinforced with geotextiles, the stiffness, length, number and spacing of the geotextile layers should be designed with great care.     

Fe2MoO4 magnetic nanocomposite modified screen printed graphite electrode as a voltammetric sensor for simultaneous determination of nalbuphine and diclofenac

Journal of Materials Science: Materials in Electronics - This study applied screen printed graphite electrode (SPGE) modified with the Fe2MoO4 magnetic nanocomposite for simultaneously determining...     

Thermoresponsive Conductivity of Graphene-Based Fibers

Smart materials are versatile material systems which exhibit a measurable response to external stimuli. Recently, smart material systems have been developed which incorporate graphene in order to share on its various advantageous properties, such as mechanical strength, electrical conductivity, and thermal conductivity as well as to achieve unique stimuli-dependent responses. Here, a graphene fiber-based smart material that exhibits reversible electrical conductivity switching at a relatively low temperature (60 °C), is reported. Using molecular dynamics (MD) simulation and density functional theory-based non-equilibrium Green's function (DFT-NEGF) approach, it is revealed that this thermo-response behavior is due to the change in configuration of amphiphilic triblock dispersant molecules occurring in the graphene fiber during heating or cooling. These conformational changes alter the total number of graphene-graphene contacts within the composite material system, and thus the electrical conductivity as well. Additionally, this graphene fiber fabrication approach uses a scalable, facile, water-based method, that makes it easy to modify material composition ratios. In all, this work represents an important step forward to enable complete functional tuning of graphene-based smart materials at the nanoscale while increasing commercialization viability.     

State of the art in passive digital image forgery detection: copy-move image forgery

Authenticating digital images is increasingly becoming important because digital images carry important information and due to their use in different areas such as courts of law as essential pieces of evidence. Nowadays, authenticating digital images is difficult because manipulating them has become easy as a result of powerful image processing software and human knowledge. The importance and relevance of digital image forensics has attracted various researchers to establish different techniques for detection in image forensics. The core category of image forensics is passive image forgery detection. One of the most important passive forgeries that affect the originality of the image is copy-move digital image forgery, which involves copying one part of the image onto another area of the same image. Various methods have been proposed to detect copy-move forgery that uses different types of transformations. The goal of this paper is to determine which copy-move forgery detection methods are best for different image attributes such as JPEG compression, scaling, rotation. The advantages and drawbacks of each method are also highlighted. Thus, the current state-of-the-art image forgery detection techniques are discussed along with their advantages and drawbacks.     

Cost minimization for bag-of-tasks workflows in a federation of clouds

We address the problem of resource allocation for bag-of-tasks (BoT) workflows in a federation of clouds and formulate it as an integer linear programming problem. The proposed model minimizes financial cost including fees for running VMs and fees for data transfer, and fulfills deadline and resource constraints in the clouds. We also formulate the problem of BoT scheduling in the hybrid clouds, and compare the financial cost in the federation of clouds with that in the hybrid clouds. Moreover, this paper discusses sensitivity analysis to investigate stability in the related allocation problem. Numerical results show that the resource allocation in the federation is considerably preferred to that in the hybrid clouds in terms of stability and cost-saving. In this paper, we also propose an approach named GRASP-FC for obtaining an approximate optimal solution of BoT scheduling in the federation. GRASP-FC is an extension of greedy randomized adaptive search procedure (GRASP), and it can be of great interest from the computational points of view.

     

Stress-Aware Periodic Test of Interconnects

Journal of Electronic Testing - Safety-critical systems have to follow extremely high dependability requirements as specified in the standards for automotive, air, and space applications. The...