scholarly journals Capillary Transport of Miniature Soft Ribbons

Micromachines ◽  
2019 ◽  
Vol 10 (10) ◽  
pp. 684
Author(s):  
Bo Chang ◽  
Heng Liu ◽  
Robin H. A. Ras ◽  
Quan Zhou
Keyword(s):  
Cantilever Beam ◽  
Target Location ◽  
Wearable Devices ◽  
Biomedical Devices ◽  
Capillary Transport ◽  
Capillary Phenomena ◽  
Miniature Device ◽  
The Subject ◽  
Theoretical Results ◽  
Miniature Devices

Manipulation of soft miniature devices is important in the construction of soft robots, wearable devices, and biomedical devices. However, transport of soft miniature devices is still a challenging task, and few studies has been conducted on the subject. This paper reports a droplet-based micromanipulation method for transporting miniature soft ribbons. We show that soft ribbons can be successfully picked up and released to the target location using water droplets. We analyze the forces involved during the process numerically and investigate the influence of the width of the ribbon on the deformation. We verify that the deformation of a soft ribbon caused by elasto-capillary phenomena can be calculated using a well-known equation for calculating the deflection of a cantilever beam. The experimental and theoretical results show that the deformability of a soft miniature device during manipulation depends on its width.

THE ALLOCATION OF CUSTOMERS IN A DISCRETE-TIME MULTI-SERVER QUEUEING SYSTEM

2010 ◽  
Vol 27 (06) ◽  
pp. 649-667 ◽  
Author(s):  
WEI SUN ◽  
NAISHUO TIAN ◽  
SHIYONG LI
Keyword(s):  
Performance Measures ◽  
Discrete Time ◽  
Queueing System ◽  
Arrival Rate ◽  
Allocation Problem ◽  
Optimal Outcome ◽  
The Subject ◽  
Multi Server ◽  
Theoretical Results

This paper, analyzes the allocation problem of customers in a discrete-time multi-server queueing system and considers two criteria for routing customers' selections: equilibrium and social optimization. As far as we know, there is no literature concerning the discrete-time multi-server models on the subject of equilibrium behaviors of customers and servers. Comparing the results of customers' distribution at the servers under the two criteria, we show that the servers used in equilibrium are no more than those used in the socially optimal outcome, that is, the individual's decision deviates from the socially preferred one. Furthermore, we also clearly show the mutative trend of several important performance measures for various values of arrival rate numerically to verify the theoretical results.

Design and Analysis of a Vibration-Based Magnetoelectric Energy Harvesting Device

2013 ◽  
Vol 722 ◽  
pp. 75-80 ◽  
Author(s):  
Zhang Zhang ◽  
Xian Zhi Dai ◽  
Yong Wang
Keyword(s):  
Magnetic Field ◽  
Cantilever Beam ◽  
Magnetic Circuit ◽  
Magnetic Field Gradient ◽  
Sensor Nodes ◽  
Ambient Vibration ◽  
Gradient Magnetic Field ◽  
Wireless Sensor Nodes ◽  
The Magnetic Field ◽  
Theoretical Results

An energy harvester is presented to harvest ambient vibration energy using a cantilever beam and multiple Terfenol-D/PMN-PT/Terfenol-D laminate magnetoelectric transducers. The harvester uses eight magnets to make up a magnetic circuit arranged on the free end of the cantilever beam. The magnetic circuit can produce a high gradient magnetic field space. The multiple transducers are placed at the high magnetic field gradient position to make the best use of the magnetic field produced by the magnets. The nonlinear vibration and electrical-output performances of the harvester at resonance are analyzed. The theoretical results indicate that the prototype can produce a load power of 7.619 mW, which is sufficient to supply low consumption wireless sensor nodes.

Hand-eye coordination during sequential tasks

1992 ◽  
Vol 337 (1281) ◽  
pp. 331-339 ◽  
Keyword(s):  
Target Location ◽  
Terminal Phase ◽  
Cognitive Mechanisms ◽  
The Gaze ◽  
Eye Fixations ◽  
Task Requirements ◽  
Before And After ◽  
Hand Eye Coordination ◽  
Main Observation ◽  
The Subject

The small angle subtended by the hum an fovea places a premium on the ability to quickly and accurately direct the gaze to targets of interest. Thus the resultant saccadic eye fixations are a very instructive behaviour, revealing much about the underlying cognitive mechanisms that guide them. Of particular interest are the eye fixations used in hand-eye coordination. Such coordination has been extensively studied for single movements from a source location to a target location. In contrast, we have studied multiple fixations where the sources and targets are a function of a task and chosen dynamically by the subject according to task requirements. T he task chosen is a copying task: subjects must copy a figure made up of contiguous coloured blocks as fast as possible. The main observation is that although eye fixations are used for the terminal phase of hand movements, they are used for other tasks before and after that phase. The analysis of the spatial and temporal details of these fixations suggests that the underlying decision process that moves the eyes leaves key decisions until just before they are required.

scholarly journals Contact lines over random topographical substrates. Part 1. Statics

2011 ◽  
Vol 672 ◽  
pp. 358-383 ◽  
Author(s):  
NIKOS SAVVA ◽  
GRIGORIOS A. PAVLIOTIS ◽  
SERAFIM KALLIADASIS
Keyword(s):  
Numerical Experiments ◽  
Random Variable ◽  
Contact Angles ◽  
Contact Lines ◽  
Substrate Roughness ◽  
Random Functions ◽  
Flat Substrate ◽  
The Subject ◽  
Influence Of Substrate ◽  
Theoretical Results

We investigate theoretically the statistics of the equilibria of two-dimensional droplets over random topographical substrates. The substrates are appropriately represented as families of certain stationary random functions parametrized by a characteristic amplitude and wavenumber. In the limit of shallow topographies and small contact angles, a linearization about the flat-substrate equilibrium reveals that the droplet footprint is adequately approximated by a zero-mean, normally distributed random variable. The theoretical analysis of the statistics of droplet shift along the substrate is highly non-trivial. However, for weakly asymmetric substrates it can be shown analytically that the droplet shift approaches a Cauchy random variable; for fully asymmetric substrates its probability density is obtained via Padé approximants. Generalization to arbitrary stationary random functions does not change qualitatively the behaviour of the statistics with respect to the characteristic amplitude and wavenumber of the substrate. Our theoretical results are verified by numerical experiments, which also suggest that on average a random substrate neither enhances nor reduces droplet wetting. To address the question of the influence of substrate roughness on wetting, a stability analysis of the equilibria must be performed so that we can distinguish between stable and unstable equilibria, which in turn requires modelling the dynamics. This is the subject of Part 2 of this study.

Experimental Verification of the Importance of The Nonlinear Curvature in the Response of a Cantilever Beam

1996 ◽  
Vol 118 (1) ◽  
pp. 21-27 ◽  
Author(s):  
T. J. Anderson ◽  
A. H. Nayfeh ◽  
B. Balachandran
Keyword(s):  
Analytical Model ◽  
Cantilever Beam ◽  
Theoretical Investigation ◽  
Experimental Verification ◽  
Dominant Role ◽  
Experimental Results ◽  
Parametrically Excited ◽  
Second Mode ◽  
Quadratic Damping ◽  
Theoretical Results

An experimental and theoretical investigation into the first- and second-mode responses of a parametrically excited slender cantilever beam is presented. Inclusion of quadratic damping in the analytical model significantly improves the agreement between the experimental and theoretical results. In addition, the experimental results verify that the often ignored nonlinear curvature terms play a dominant role in the response of the first mode and that the nonlinear inertia terms play a dominant role in the response of the second mode.

scholarly journals NUMERICAL EXPERIMENTS FOR THE ESTIMATION OF MEAN DENSITIES OF RANDOM SETS

2014 ◽  
Vol 33 (2) ◽  
pp. 83 ◽  
Author(s):  
Federico Camerlenghi ◽  
Vincenzo Capasso ◽  
Elena Villa
Keyword(s):  
Numerical Experiments ◽  
Random Sets ◽  
Density Estimator ◽  
Absolutely Continuous ◽  
Minkowski Content ◽  
Closed Sets ◽  
Random Closed Sets ◽  
Spatially Inhomogeneous ◽  
The Subject ◽  
Theoretical Results

Many real phenomena may be modelled as random closed sets in ℝd, of different Hausdorff dimensions. The problem of the estimation of pointwise mean densities of absolutely continuous, and spatially inhomogeneous, random sets with Hausdorff dimension n < d, has been the subject of extended mathematical analysis by the authors. In particular, two different kinds of estimators have been recently proposed, the first one is based on the notion of Minkowski content, the second one is a kernel-type estimator generalizing the well-known kernel density estimator for random variables. The specific aim of the present paper is to validate the theoretical results on statistical properties of those estimators by numerical experiments. We provide a set of simulations which illustrates their valuable properties via typical examples of lower dimensional random sets.

scholarly journals Analysis of Vertical Displacements of the Esperanto Footbridge in Bydgoszcz

2018 ◽  
Vol 28 (2) ◽  
pp. 5-17 ◽  
Author(s):  
Adam Bujarkiewicz ◽  
Jarosław Gajewski ◽  
Tomasz Janiak ◽  
Justyna Sobczak-Piąstka ◽  
Jacek Sztubecki ◽  
...  
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Numerical Simulations ◽  
The Finite Element Method ◽  
Test Load ◽  
Vertical Displacements ◽  
The Subject ◽  
Theoretical Results ◽  
Element Method

Abstract The subject of the research is a footbridge across the river Brda in Bydgoszcz. The measurements of the footbridge displacements with the test load were undertaken. The paper presents the results of the measurements and compares them with the theoretical results obtained using the finite element method (FEM). On this basis, discrepancy between actual work of the structure and numerical simulations was found. Attempt to explain the reasons for the observed differences and direction of further research were included in the conclusions.

Conclusions

2016 ◽  
pp. 289-299
Author(s):  
Don Kerr ◽  
John Gammack
Keyword(s):  
Research Agenda ◽  
Social Research ◽  
Wearable Devices ◽  
Future Research ◽  
Subject Domain ◽  
Ethical Considerations ◽  
Privacy And Security ◽  
Future Research Agenda ◽  
Use Of Data ◽  
The Subject

This chapter provides a contemporary example of how data from wearable devices can be used for “big data” type research. It then asked the question of data policies for the use of data generated by wearable devices. This is followed by an overview of the chapters in the book and how they fit within the general theme of the book. In addition, each chapter is categorised into whether it is social research or more technical type research. The chapter also includes concluding suggestions on the possible future research agenda for privacy and security within the subject domain of the use of wearables. In addition, insights into the future of wearables in relation to ethical considerations, privacy, security and data ownership is also given.

The Effect of Thermal Bridges on Energy Balance of Wood Frame Houses

2016 ◽  
Vol 824 ◽  
pp. 323-330 ◽  
Author(s):  
Tibor Varga ◽  
Rastislav Ingeli
Keyword(s):  
Energy Balance ◽  
Building Materials ◽  
Simulation Method ◽  
Critical Surface ◽  
Dynamic Boundary Conditions ◽  
Sandwich Construction ◽  
The Subject ◽  
Thermal Bridges ◽  
Wood Frame ◽  
Theoretical Results

In compliance with the today’s trend of designing sustainable and energy-saving architecture, it is necessary to firstly solve the factors influencing the energy balance. In this respect, the thermal bridges in buildings constitute a crucial factor. In case of their occurrence, the use of construction and insulation building materials is significant for finding the solution. The aim of this paper is to analyse the thermal bridges in buildings constructed on the basis of light constructions. The subject of analysis was an implemented wood frame house with common sandwich construction, designed in a low-energy standard. The house analysis is divided in theoretical and experimental part. The house in question has been directly exposed to dynamic boundary conditions. In order to analyse the thermal bridges, critical details have been selected methodically, verified by thermography. The experimental and theoretical results were compared by the simulation method for calculating critical surface temperatures. Both the measurements and results show how attention shall be paid to this issue at the project stage already. With increasing demands for overall energy balance of buildings, it is necessary to exactly define the critical details and consider the thermal bridges in the project documentation already.

Supersonic cooling by shock–vortex interaction

1996 ◽  
Vol 308 ◽  
pp. 363-379 ◽  
Author(s):  
M. D. Fox ◽  
M. Kurosaka
Keyword(s):  
Heat Transfer ◽  
Supersonic Jet ◽  
Vortex Interaction ◽  
Vortical Structures ◽  
The Past ◽  
Impingement Plate ◽  
Temperature Separation ◽  
Total Temperature ◽  
The Subject ◽  
Theoretical Results

The subject of total temperature separation in jets was treated in Fox et al. (1993) for subsonic jets. When we extended this study to the case of supersonic jets, we found the presence of a different mechanism of cooling, an effect which does not appear to have been known in the past. Named the ‘shock-induced total temperature separation’, this cooling can be of much greater magnitude than the subsonic cooling treated previously; it is caused by the interaction of convected vortical structures near the jet exhaust with the shock structure of the supersonic jet.In studying this phenomenon, we focus our attention on overexpanded jets exiting a convergent-divergent nozzle. The theoretical results for the shock-induced cooling which are based on a linearized, unsteady supersonic analysis are shown to agree favourably with experiments.When an impingement plate is inserted, the shock-induced cooling would manifest itself as wall cooling, whose magnitude is significantly larger than the subsonic counterpart. This has implications for heat transfer not only in jets, but wherever vortical structures may interact with shock waves.

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