1,816 research outputs found
Data Security using Reversible Data Hiding with Optimal Value Transfer
In this paper a novel reversible data hiding algorithm is used which can recover image without any distortion. This algorithm uses zero or minimum points of an image and modifies the pixel. It is proved experimentally that the peak signal to noise ratio of the marked image generated by this method and the original image is guaranteed to be above 48 dB this lower bound of peak signal to noise ratio is much higher than all reversible data hiding technique present in the literature. Execution time of proposed system is short. The algorithm has been successfully applied to all types of images
Ionic liquid catalyzed one pot green synthesis of isoxazolone derivatives via multicomponent reaction
459-464A series of 3-methyl-4-((3-aryl-1-phenyl-1H-pyrazol-4-yl)methylene)isoxazol-5(4H)-one derivatives have been efficiently synthesized by environmentally benign, one-pot three component condensation of substituted 1,3-diaryl-1H-pyrazole-4-carboxyaldehyde, β-keto ester and hydroxyl amine hydrochloride in the presence of ionic liquid [HNMP][HSO4] as a catalyst in ethanol. These derivatives have been synthesized by conventional, ultrasound and microwave irradiation methods. The combination of ionic liquid with ultrasound as well as microwave irradiation makes the protocol fascinating and environmentally benign. In addition, it has several benefits such as simple work-up procedure, clean reaction profile, short reaction time and good yields
Automated team selection and compliance checking in business processes
Plenty of activities in many business contexts must be performed
collaboratively, e.g., in a hospital or when organising
a conference. Tasks such as team composition and allocation
are usually performed manually and on the ground of
limited criteria such as individual skills, a.o. because adequate
automatic support is missing. This paper addresses
this shortcoming. We present an approach for team selection
and compliance checking in business processes, which
includes (i) a language for describing teams; (ii) a way to de-
ne team selection conditions and policies related to team
composition; and (iii) a mechanism for the automatic resolution
of the team selection conditions and for team-related
compliance checking based on formal ontologies.Austrian Research Funding Association (FFG) 845638 (SHAPE)Ministerio de Ciencia e Innovación TIN2009-07366 (SETI)Ministerio de Economía y Competitividad TIN2012-32273 (TAPAS)Junta de Andalucía TIC-5906 (THEOS
Dense active matter model of motion patterns in confluent cell monolayers
Epithelial cell monolayers show remarkable displacement and velocity
correlations over distances of ten or more cell sizes that are reminiscent of
supercooled liquids and active nematics. We show that many observed features
can be described within the framework of dense active matter, and argue that
persistent uncoordinated cell motility coupled to the collective elastic modes
of the cell sheet is sufficient to produce swirl-like correlations. We obtain
this result using both continuum active linear elasticity and a normal modes
formalism, and validate analytical predictions with numerical simulations of
two agent-based cell models, soft elastic particles and the self-propelled
Voronoi model together with in-vitro experiments of confluent corneal
epithelial cell sheets. Simulations and normal mode analysis perfectly match
when tissue-level reorganisation occurs on times longer than the persistence
time of cell motility. Our analytical model quantitatively matches measured
velocity correlation functions over more than a decade with a single fitting
parameter.Comment: updated version accepted for publication in Nat. Com
Integrating BDI agents with Agent-based simulation platforms
Agent-Based Models (ABMs) is increasingly being used for exploring and supporting decision making about social science scenarios involving modelling of human agents. However existing agent-based simulation platforms (e.g., SWARM, Repast) provide limited support for the simulation of more complex cognitive agents required by such scenarios. We present a framework that allows Belief-Desire Intention (BDI) cognitive agents to be embedded in an ABM system. Architecturally, this means that the "brains" of an agent can be modelled in the BDI system in the usual way, while the "body" exists in the ABM system. The architecture is exible in that the ABM can still have non-BDI agents in the simulation, and the BDI-side can have agents that do not have a physical counterpart (such as an organisation). The framework addresses a key integration challenge of coupling event-based BDI systems, with time-stepped ABM systems. Our framework is modular and supports integration off-the-shelf BDI systems with off-the-shelf ABM systems. The framework is Open Source, and all integrations and applications are available for use by the modelling community
Asperity level tribological investigation of automotive bore material and coatings
Choosing in-cylinder surfaces is complex. A well-chosen surface has low friction and wear. Conversely, poor oversight often leads to premature failure through wear and scuffing. Typically cylinder bore surfaces are selected experientially. This paper demonstrates the use of Atomic Force Microscopy in LFM mode, characterising typical cylinder bore materials and coatings. The approach uses integrated LFM with continuum contact mechanics. It evaluates the real contact area and effective elastic modulus of the surface, including the effect of any reactive surface film. Surface energy and shear strength, as well as the coefficient of friction in nanoscale interactions are also determined. These properties are measured for 6 cylinder bore materials, including for composite Nickel-Silicon Carbide and DLC, used for high performance engines
Direct Observation of the Dynamics of Latex Particles Confined inside Thinning Water-Air Films
The dynamics of micrometer-size polystyrene latex particles confined in thinning foam films was
investigated by microscopic interferometric observation. The behavior of the entrapped particles depends
on the mobility of the film surfaces, the particle concentration, hydrophobicity, and rate of film formation.
When the films were stabilized by sodium dodecyl sulfate, no entrapment of particles between the surfaces
was possible. When protein was used as a stabilizer, a limited number of particles were caught inside
the film area due to the decreased mobility of the interfaces. In this case, extraordinary long-ranged (>100
Ìm) capillary attraction leads to two-dimensional (2D) particle aggregation. A major change occurs when
the microspheres are partially hydrophobized by the presence of cationic surfactant. After the foam films
are opened and closed a few times, a layer of particles simultaneously adsorbed to the two interfaces is
formed, which sterically inhibits any further film opening and thinning. The particles within this layer
show an excellent 2D hexagonal ordering. The experimental data are relevant to the dynamics of defects
in coating films, Pickering emulsions, and particle assembly into 2D arrays
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