439 research outputs found
Design Optimization for an Electro-Thermally Actuated Polymeric Microgripper
Thermal micro-actuators are a promising solution to the need for
large-displacement, gentle handling force, low-power MEMS actuators. Potential
applications of these devices are micro-relays, assembling and miniature
medical instrumentation. In this paper the development of thermal
microactuators based on SU-8 polymer is described. The paper presents the
development of a new microgripper which can realize a movement of the gripping
arms with possibility for positioning and manipulating of the gripped object.
Two models of polymeric microgripper electrothermo- mechanical actuated, using
low actuation voltages, designed for SU-8 polymer fabrication were presented.
The electro-thermal microgrippers were designed and optimized using finite
element simulations. Electro-thermo-mechanical simulations based on finite
element method were performed for each of the model in order to compare the
results. Preliminary experimental tests were carried out.Comment: Submitted on behalf of EDA Publishing Association
(http://irevues.inist.fr/handle/2042/16838
Analytical results regarding electrostatic resonances of surface phonon/plasmon polaritons: separation of variables with a twist
The boundary integral equation method ascertains explicit relations between
localized surface phonon and plasmon polariton resonances and the eigenvalues
of its associated electrostatic operator. We show that group-theoretical
analysis of Laplace equation can be used to calculate the full set of
eigenvalues and eigenfunctions of the electrostatic operator for shapes and
shells described by separable coordinate systems. These results not only unify
and generalize many existing studies but also offer the opportunity to expand
the study of phenomena like cloaking by anomalous localized resonance. For that
reason we calculate the eigenvalues and eigenfunctions of elliptic and circular
cylinders. We illustrate the benefits of using the boundary integral equation
method to interpret recent experiments involving localized surface phonon
polariton resonances and the size scaling of plasmon resonances in graphene
nano-disks. Finally, symmetry-based operator analysis can be extended from
electrostatic to full-wave regime. Thus, bound states of light in the continuum
can be studied for shapes beyond spherical configurations.Comment: 25 pages, 3 figures, to be published Proc. Royal Soc.
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Presentation a technical solution that can achieve longitudinal connectivity (upstream-downstream) of the Crişul Repede River
The production deployment of IPv6 on WLCG
The world is rapidly running out of IPv4 addresses; the number of IPv6 end systems connected to the internet is increasing; WLCG and the LHC experiments may soon have access to worker nodes and/or virtual machines (VMs) possessing only an IPv6 routable address. The HEPiX IPv6 Working Group has been investigating, testing and planning for dual-stack services on WLCG for several years. Following feedback from our working group, many of the storage technologies in use on WLCG have recently been made IPv6-capable. This paper presents the IPv6 requirements, tests and plans of the LHC experiments together with the tests performed on the group's IPv6 test-bed. This is primarily aimed at IPv6-only worker nodes or VMs accessing several different implementations of a global dual-stack federated storage service. Finally the plans for deployment of production dual-stack WLCG services are presented
MonALISA : A Distributed Monitoring Service Architecture
The MonALISA (Monitoring Agents in A Large Integrated Services Architecture)
system provides a distributed monitoring service. MonALISA is based on a
scalable Dynamic Distributed Services Architecture which is designed to meet
the needs of physics collaborations for monitoring global Grid systems, and is
implemented using JINI/JAVA and WSDL/SOAP technologies. The scalability of the
system derives from the use of multithreaded Station Servers to host a variety
of loosely coupled self-describing dynamic services, the ability of each
service to register itself and then to be discovered and used by any other
services, or clients that require such information, and the ability of all
services and clients subscribing to a set of events (state changes) in the
system to be notified automatically. The framework integrates several existing
monitoring tools and procedures to collect parameters describing computational
nodes, applications and network performance. It has built-in SNMP support and
network-performance monitoring algorithms that enable it to monitor end-to-end
network performance as well as the performance and state of site facilities in
a Grid. MonALISA is currently running around the clock on the US CMS test Grid
as well as an increasing number of other sites. It is also being used to
monitor the performance and optimize the interconnections among the reflectors
in the VRVS system.Comment: Talk from the 2003 Computing in High Energy and Nuclear Physics
(CHEP03), La Jolla, Ca, USA, March 2003, 8 pages, pdf. PSN MOET00
Joint Estimation of Sequential Labor Force Participation and Fertility Decisions Using Markov Chain Monte Carlo Techniques
In this paper we estimate the causal effect of children on the labor supply of women using panel data on women from the 1979 National Longitudinal Survey of Youth (NLSY79). We examine the effect of children both prior to and after birth as well as how the effect of children varies with the number of children. We also decompose the total effect of children into the direct and indirect components and separately examine the dynamics of these components. Sequential participation decisions for four levels of labor market involvement and fertility decisions are jointly modeled. We allow decisions to be correlated in a general fashion both across time and across choices. The estimation is performed using Markov chain Monte Carlo methods. We find that children have a strong effect on a women's labor market behavior in the post-birth period and that differences in expected fertility have a strang effect on labor market behavior in the pre-birth period. We also find that both the direct and indirect effects are large immediately after the birth of a child but that the indirect effect declines quickly over time. The effects of children vary by education and race
Clutter modeling in infrared images using genetic programming
Background clutter characterization in infrared imagery has become an actively researched field, and several clutter models have been reported. These models attempt to evaluate the target detection and recognition probabilities that are characteristic of a certain scene when specific target and human visual perception features are known. The prior knowledge assumed and required by these models is a severe limitation. Furthermore, the attempt to model subjective and intricate mechanisms such as human perception with general mathematical formulas is controversial, in this paper, we introduce the idea of adaptive models that are dynamically derived from a set of examples by a supervised learning mechanism based on genetic programming foundations. A set of characteristic scene and target features with a demonstrated influence on the human visual perception mechanism is first extracted from the original images. Then, the correlations between these features and detection performance results obtained by visual observer tests on the same set of images are captured into models by a learning algorithm. The effectiveness of the adaptive modeling principle is discussed in the final part of the paper
Influence of sorghum inclusion in fattening steers diets on health and fatty acids profile of Longissimus dorsi muscle
The study was conducted using 21 Romanian Black Spotted fattening steers to determine the effects of sorghum grains on health and fatty acid profile of Longissimus dorsi muscle. The animals were assigned uniformly to 3 groups of 7 steers each, which received different treatments: control (C) received a compound feed without sorghum grains, experimental group (E1) received 15% sorghum grains in the compound feed, while next experimental group (E2) received 25% sorghum grains in the compound feed. To determine the biochemical parameters, blood samples were collected from animals at the end of experimental period. The laboratory analyses conducted on samples of Longissimus dorsi muscle collected from the 3 experimental groups, showed changes in the fatty acid composition. The proportion of saturated fatty acids (SFA) decreased in favour of the unsaturated fatty acids (UFA) with 1.04% in group E2, while the proportion of unsaturated fatty acids increased from 53.00% in the control group to 54.19% in group E2
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