Subharmonic Venture

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Term Evaluator: A Tool for Terminology Annotation and Evaluation

There are several methods and available tools for terminology extraction, but the quality of the extracted terms is not always high. Hence, an important consideration in terminology extraction is to assess the quality of the extracted terms. In this paper, we propose and make available a tool for annotating the correctness of terms extracted by three term-extraction tools. This tool facilitates term annotation by using a domain-specific dictionary, a set of filters, and an annotation memory, and allows for post-hoc evaluation. We present a study in which two human judges used the developed tool for term annotation. Their annotations were then analyzed to determine the efficiency of term extraction tools by measures of precision, recall, and F-score, and to calculate the inter-annotator agreement rate

Local-Global Vectors to Improve Unigram Terminology Extraction

The present paper explores a novel method that integrates efficient distributed representations with terminology extraction. We show that the information from a small number of observed instances can be combined with local and global word embeddings to remarkably improve the term extraction results on unigram terms. To do so, we pass the terms extracted by other tools to a filter made of the local-global embeddings and a classifier which in turn decides whether or not a term candidate is a term. The filter can also be used as a hub to merge different term extraction tools into a single higher-performing system. We compare filters that use the skipgram architecture and filters that employ the CBOW architecture for the task at hand

Electric-Double-Layer-Modulation Microscopy

The electric double layer (EDL) formed around charged nanostructures at the liquid-solid interface determines their electrochemical activity and influences their electrical and optical polarizability. We experimentally demonstrate that restructuring of the EDL at the nanoscale can be detected by dark-field scattering microscopy. Temporal and spatial characterization of the scattering signal demonstrates that the potentiodynamic optical contrast is proportional to the accumulated charge of polarisable ions at the interface and its time derivative represents the nanoscale ionic current. The material-specificity of the EDL formation is used in our work as a label-free contrast mechanism to image nanostructures and perform spatially-resolved cyclic voltametry on ion current density of a few attoamperes, corresponding to the exchange of only a few hundred ions.Comment: 6 pages, 4 figrue

Self-demodulation effect on subharmonic response of ultrasound contrast agent

In this work the use of the self-demodulation (S-D) signal as a mean of microbubble excitation at the subharmonic (SH) frequency to enhance the SH emission of ultrasound contrast agent (UCA) is studied. SH emission from the UCA is of interest since it is produced only by the UCA and is free of the artifacts produced in harmonic imaging modes. The S-D wave is a low-frequency signal produced by nonlinear propagation of an ultrasound wave in the medium. Single element transducer experiments and numerical simulations were conducted at 10 MHz to study the effect of the S-D signal on the SH response of the UCA by modifying the envelope of the excitation bursts. For 6 and 20 transmitted cycles, the SH response is increased up to 25 dB and 22 dB because of the S-D stimulation for a burst with a rectangular envelope compared with a Gaussian envelope burst. Such optimized excitations were used in an array-based micro-ultrasound system (Vevo 2100, VisualSonics Inc., Toronto, ON, Canada) at 18 MHz for in vitro validation of SH imaging. This study suggests that a suitable design of the envelope of the transmit excitation to generate a S-D signal at the SH frequency can enhance the SH emission of UCA and real-time SH imaging is feasible with shorter transmit burst (6- cycle) and low acoustic pressure (-150 KPa) at high frequencies (>15 MHz)

An outbreak of Glasser’s disease from two farms in Malaysia

Haemophilus parasuis is an endemic bacterial pathogen in pig farms worldwide. In this report, we investigated a suspected case of Glasser’s disease in 3-9 weeks old Landrace cross Duroc piglets from two pig farms. The farmers reported the case to the Veterinary Hospital of University Malaysia Kelantan, with the complaint of anorexia, depression and weakness. On physical examination, the piglets were found to be smaller in size and had rough hair coat. Clinical signs included swollen hock joint, labored abdominal breathing and tremors. Post-mortem evaluation of culled moribund piglets showed pneumonic lesions in the lung, polyarthritis of the hock joint, cerebral congestion, meningitis, renal cortical heamorrhage and polyserositis. Histo-pathological examination showed interstitial pneumonia with emphysema, encephalitis, encephalomalacia with gliosis and vacuolar degeneration of the hepatocytes. Bacteriological culture of swab samples from infected organs revealed the growth of satellitic small colonies on blood culture suggestive of H. parasuis. Ceftiofur injection (HIPRA, Malaysia, 3mg kg-1i.m), phenoxymethyl penicillin (Norvatis Animal Health, Australia at 200g T-1 of feed) and amoxicillin (Norvatis Animal Health at 15-30g 100L-1 of water) were effective in reducing morbidity and reversing clinical signs. Prompt diagnosis and treatment of Glasser’s disease in pig farms is paramount in order to curtail its menace and prevent serious economic losses

GA-based heuristic algorithms for bandwidth-delay-constrained least-cost multicast routing

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Motion-Induced Radiation from a Dynamically Deforming Mirror

A path integral formulation is developed to study the spectrum of radiation from a perfectly reflecting (conducting) surface. It allows us to study arbitrary deformations in space and time. The spectrum is calculated to second order in the height function. For a harmonic traveling wave on the surface, we find many different regimes in which the radiation is restricted to certain directions. It is shown that high frequency photons are emitted in a beam with relatively low angular dispersion whose direction can be controlled by the mechanical deformations of the plate.Comment: 4 pages, 2 eps figues included, final version as appeared in PR

Multifractal analysis of the electronic states in the Fibonacci superlattice under weak electric fields

Influence of the weak electric field on the electronic structure of the Fibonacci superlattice is considered. The electric field produces a nonlinear dynamics of the energy spectrum of the aperiodic superlattice. Mechanism of the nonlinearity is explained in terms of energy levels anticrossings. The multifractal formalism is applied to investigate the effect of weak electric field on the statistical properties of electronic eigenfunctions. It is shown that the applied electric field does not remove the multifractal character of the electronic eigenfunctions, and that the singularity spectrum remains non-parabolic, however with a modified shape. Changes of the distances between energy levels of neighbouring eigenstates lead to the changes of the inverse participation ratio of the corresponding eigenfunctions in the weak electric field. It is demonstrated, that the local minima of the inverse participation ratio in the vicinity of the anticrossings correspond to discontinuity of the first derivative of the difference between marginal values of the singularity strength. Analysis of the generalized dimension as a function of the electric field shows that the electric field correlates spatial fluctuations of the neighbouring electronic eigenfunction amplitudes in the vicinity of anticrossings, and the nonlinear character of the scaling exponent confirms multifractality of the corresponding electronic eigenfunctions.Comment: 10 pages, 9 figure

Nonlinear optical memory effect

Light propagating through random media produces characteristic speckle patterns, directly related to the large multitude of scattering events. These complex dynamics remarkably display robustness to perturbation of the incoming light parameters, maintaining correlation in the scattered wavefront. This behavior is known as the optical memory effect. Here we unveil the properties of the nonlinear optical memory effect, which occurs when an optothermal nonlinearity perturbs the random material. The effect is characterized through a series of pump and probe experiments in silica aerogel, in the visible range. This additional degree of freedom further generalizes the memory effect, opening the road to applications based on the nonlinear response of random media. (C) 2019 Optical Society of Americ