On the First-Order Decoupling of Dynamical Equations of Motion for Elastic Multibody Systems as Applied to a Two-Link Flexible Manipulator

An improved method for deriving elastic generalized coordinatesis considered. Then Kane's equations of motion for multibody systemsconsisting of an arbitrary number of rigid and elastic bodies ispresented. The equations are in general form and are applicable for anydesired holonomic system. Flexibility in choosing generalized speeds interms of generalized coordinate derivatives in Kane's method is used. Itis shown that proper choice of a congruency transformation betweengeneralized coordinate derivatives and generalized speeds leads toequations of motion for holonomic multibody systems consisting of anarbitrary number of rigid and elastic bodies. These equations aredecoupled in first-order terms. In order to show the use of this method,a simple system consisting of a lumped mass, a spring and a clamped-freeelastic beam is modeled. Finally, the numerical implementation ofdecoupling using congruency transformation is discussed and shown viasimulation of a two-degrees-of-freedom flexible robot.     

Resource Allocation and Outage Control for Solar-Powered WLAN Mesh Networks

In this paper, resource allocation and outage control are considered for solar-powered WLAN mesh networks. Solar-powered nodes are a very cost effective option in WLAN mesh deployments where continuous power sources are not practical. In such nodes, the cost of the solar panel and battery can be a significant fraction of the total and, therefore, reducing AP power consumption is very important. A solar panel/battery configuration methodology is introduced based on a proposed AP power-aware version of IEEE 802.11. Public meteorological data is used to provision each node based on an averaged offered capacity profile. Since a node is configured statistically, it is possible that future loading may result in nonzero outage even when negligible outage is the design target. Control algorithms are introduced which can improve node outage performance by sometimes introducing an access point capacity deficit. Results are presented which show the value of the proposed configuration methodology and show that the control algorithms can prevent outage even at high levels of excess loading.     

Airfoil profile reconstruction under the uncertainty of inspection data points

A manufactured aero-engine blade is commonly inspected in sections, and its geometric errors are evaluated from the sectional inspection data points. To maintain consistency in evaluating the geometric errors, in particular, the position and twist errors of the stacked blade sections, reconstruction of valid sectional airfoil profiles from the measurement points is preferred. Considering that inspection data points are subject to measurement uncertainty, profile reconstruction via approximation-based curve fitting, rather than interpolation-based curve reconstruction, is adopted in this work. The fitting error of the approximated airfoil profile is deemed equivalent to the measurement uncertainty in the inspection data points. Thus, according to a given measurement uncertainty value, a progressive curve fitting scheme is proposed to generate the airfoil profile that meets the measurement uncertainty constraint. A closed nonperiodic B-spline curve is utilized to model the reconstructed airfoil profile due to its versatility in closed curve approximation. Typical computational tests have been carried out to demonstrate the effectiveness of the proposed airfoil profile reconstruction method, which is in fact generic and can be equally applied to approximating other closed sectional profiles.     

A novel method for coating of carbon nanotube on cellulose fiber using 1,2,3,4-butanetetracarboxylic acid as a cross-linking agent

Carbon nanotubes (CNTs) were coated by the exhaustion method and stabilized on a cotton surface using 1,2,3,4-butanetetracarboxylic acid (BTCA) as a crosslinking agent and sodium hypophosphite (SHP) as a catalyst. The Influence of CNTs on the performance of the cellulose fiber was investigated using Fourier transform infrared spectrophotometer (FTIR), thermo-gravimetric analyzer, scanning electron microscope (SEM), zeta potential analyzer, reflectance spectroscope, wrinkle recovery tester and bacteriological culture tube. The possible interactions between CNTs, the cross-linking agent and cellulose functional groups at the surface were elucidated by FTIR spectroscopy. The results indicated that the stabilized CNTs modify the surface of the fibers and increase the thermal stability of the substrate. SEM showed a uniform coating of CNTs on the fiber surface.     

Quantum Cooperative Robotics and Autonomy

The intersection of Quantum Technologies and Robotics Autonomy is explored in the present paper.The two areas are brought together in establishing an interdisci...     

A Survey of PSO-Based Scheduling Algorithms in Cloud Computing

Cloud computing provides effective mechanisms for distributing the computing tasks to the virtual resources. To provide cost-effective executions and achieve objectives such as load balancing, availability and reliability in the cloud environment, appropriate task and workflow scheduling solutions are needed. Various metaheuristic algorithms are applied to deal with the problem of scheduling, which is an NP-hard problem. This paper presents an in-depth analysis of the Particle Swarm Optimization (PSO)-based task and workflow scheduling schemes proposed for the cloud environment in the literature. Moreover, it provides a classification of the proposed scheduling schemes based on the type of the PSO algorithms which have been applied in these schemes and illuminates their objectives, properties and limitations. Finally, the critical future research directions are outlined.     

New loss functions to improve deep learning estimation of heat transfer

Neural Computing and Applications - Deep neural networks (DNNs) are promising alternatives to simulate physical problems. These networks are capable of eliminating the requirement of numerical...     

A part-level learning strategy for JPEG image recompression detection

Multimedia Tools and Applications - Recompression is a prevalent form of multimedia content manipulation. Different approaches have been developed to detect this kind of alteration for digital...