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This paper describes a robust method for crease detection and curvature estimation on large, noisy triangle meshes. We assume that these meshes are approximations of piecewise-smooth surfaces derived from range or medical imaging ...
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This paper describes a robust method for crease detection and curvature estimation on large, noisy triangle meshes. We assume that these meshes are approximations of piecewise-smooth surfaces derived from range or medical imaging systems and thus may exhibit measurement or even registration noise. The proposed algorithm, which we call normal vector voting, uses an ensemble of triangles in the geodesic neighborhood of a vertex―instead of its simple umbrella neighborhood―to estimate the orientation and curvature of the original surface at that point. With the orientation information, we designate a vertex as either lying on a smooth surface, following a crease discontinuity, or having no preferred orientation. For vertices on a smooth surface, the curvature estimation yields both principal curvatures and principal directions while for vertices on a discontinuity we estimate only the curvature along the crease. The last case for no preferred orientation occurs when three or more surfaces meet to form a corner or when surface noise is too large and sampling density is insufficient to determine orientation accurately. To demonstrate the capabilities of the method, we present results for both synthetic and real data and compare these results to the G. Taubin (1995, in Proceedings of the Fifth International Conference on Computer Vision, pp. 902-907) algorithm. Additionally, we show practical results for several large mesh data sets that are the motivation for this algorithm.
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A discrete-time algorithm for simple adaptive control, proposed by one of authors, circumvents some drawbacks of the algorithm derived directly from continuous-time one. However, it leaves steady-state output error between a contr...
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A discrete-time algorithm for simple adaptive control, proposed by one of authors, circumvents some drawbacks of the algorithm derived directly from continuous-time one. However, it leaves steady-state output error between a controlled plant and a reference model. This paper proposes a modified algorithm, which removes the steady-state output error. The stability of the algorithm is proved based on asymptotic output tracker theory, instead of command generator tracker theory. Finally, simulation results illustrate satisfactory control performance, that verifies the usefulness of the proposed algorithm.
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Wurtzite A1N films were deposited by an RF reactive sputtering technique under various nitrogen concentrations at low temperature (350℃). The evolution of preferred orientation and morphology of the deposited films were studied b...
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Wurtzite A1N films were deposited by an RF reactive sputtering technique under various nitrogen concentrations at low temperature (350℃). The evolution of preferred orientation and morphology of the deposited films were studied by X-ray diffraction, field emission scanning electron microscopy. The vibrational phonon modes of A1N films were studied using a Fourier transform infrared (FTTR) spectrometer and a Raman spectrometer. Tt was found that at. low nitrogen concentration, the films showed (100) preferred orientation. With increase in nitrogen concentration the films tend to be more randomly orientated as all the (100), (101), (002) peaks appeared. A further increase in nitrogen concentration resulted in c-axis (002) orientated films. The morphology of the deposited films also changed from facet to pebble-like grain structure. The formation mechanism of the preferred orientation and morphology is discussed and related to the deposition conditions. Two peaks were found in FTIR spectra and were attributed to E_1(TO) and A_1(TO) phonon modes. The shift of E_1(TO) peak towards high wave number indicated that increased compressive stress developed in the deposited films with increase in nitrogen concentration. The major peak observed in Raman spectra was identified as being due to E_2~2 phonon modes. The measured vibrational spectra results were related to the microstruclure of the deposited films.
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Coatings are usually used to improve the functional properties of many engineering components. A recent exciting development has been studied by designing the structure of these engineering coatings through the use of multiple lay...
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Coatings are usually used to improve the functional properties of many engineering components. A recent exciting development has been studied by designing the structure of these engineering coatings through the use of multiple layers of different materials. This study addresses the development of multilayer Ti/TiB_2 coatings with increased adhesion to the substrate and retained high hardness. Multilayer Ti/TiB_2 coatings were deposited on stationary high-speed steel substrates by magnetron sputtering. Multilayer Ti/TiB_2 coatings were evaluated with respect to fundamental properties such as structure, fractured cross-section, surface roughness, hardness, modulus and coating adhesion. It was found that the adhesion of resultant coatings was increased with increased alternate Ti/TiB_2 layers, whilst the hardness was slightly increased. The effects of alternate layers on other structural and property features of the resultant coatings are also discussed in this paper.
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There is a growing trend toward emotional intelligence in human-computer interaction paradigms. In order to react appropriately to a human, the computer would need to have some perception of the emotional state of the human. We as...
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There is a growing trend toward emotional intelligence in human-computer interaction paradigms. In order to react appropriately to a human, the computer would need to have some perception of the emotional state of the human. We assert that the most informative channel for machine perception of emotions is through facial expressions in video. One current difficulty in evaluating automatic emotion detection is that there are currently no international databases which are based on authentic emotions. The current facial expression databases contain facial expressions which are not naturally linked to the emotional state of the test subject. Our contributions in this work are twofold: first, we create the first authentic facial expression database where the test subjects are showing the natural facial expressions based upon their emotional state. Second, we evaluate the several promising machine learning algorithms for emotion detection which include techniques such as Bayesian networks, SVMs, and decision trees.
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Single molecule spectroscopy can uncover fluctuation averaged out in ensemble measurements. In addition, single molecule spectroscopy naturally implies ultra-sensitive measurements, which should play important role in future prote...
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Single molecule spectroscopy can uncover fluctuation averaged out in ensemble measurements. In addition, single molecule spectroscopy naturally implies ultra-sensitive measurements, which should play important role in future proteomics and genomic research. Fluorescence method is the most commonly used single molecule detection. In this paper, we will use single conjugated polymer fluorescence spectroscopy to illustrate the power of this technique.
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In dilute magnetic oxide hexagonal Ba(Ti_(0.9)Fe_(0.1))O_(2.81) bulk ceramic, we report on combined ferromagnetism and improper ferroelectricity as well as cross-controlled magnetoelectric effects at room temperature. The annular-...
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In dilute magnetic oxide hexagonal Ba(Ti_(0.9)Fe_(0.1))O_(2.81) bulk ceramic, we report on combined ferromagnetism and improper ferroelectricity as well as cross-controlled magnetoelectric effects at room temperature. The annular-bright-field (ABF) imaging technique in scanning transmission electron microscopy (STEM) demonstrates an oxygen vacancy ordering in the hexagonal closest-packed Bal-Ol layers and severe distortion of the octahedra and pyramids. Strong dependencies of the susceptibility on temperature and magnetic field as well as the frequency dependence of magnetization under an ac electric field reveal that the intrinsic ferromagnetism of the highly insulating system dynamically evolves from a paramagnetic ground state, and dynamic exchanges of trapped electrons in the ordered polarons are attributed to the ferromagnetic interaction. Accordingly, aided by the motion of oxygen vacancies, responses of the trapped electrons to the ac magnetic field result in the reversal of magnetically induced voltages between high and low states. Our results not only expand our understanding on the magnetoelectric coupling mechanism, but also provide a grand opportunity toward designing novel multiferroic materials through introducing ordered point defects into a centrosymmetric matrix.
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We have traced the development of the Ni electronic structure with thickness variation on flat and nano-structured Cu(001) surfaces by means of photoemission spectroscopy. The binding energy of the Ni 2p_(3/2) main peak and satell...
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We have traced the development of the Ni electronic structure with thickness variation on flat and nano-structured Cu(001) surfaces by means of photoemission spectroscopy. The binding energy of the Ni 2p_(3/2) main peak and satellite peak is found to have shifted monotonically in the direction opposite to each other, with the increase of Ni coverage. The reduced binding energy of the thin film's main peak is strongly correlated to the Cu 4s/Ni 3d interfacial hybridization effect (s/d 1HE) and the narrowing of the d band with the reduction of dimensions, while the increased satellite binding energy results from the combination of interface hybridization and expansion of an extended 4s-!ike state towards the vacuum. The center of the Ni d_(xy) band is predicted to shift closer to the Fermi level with increasing film thickness. Enhanced satellite intensity in thin films is observed, correlating to the narrowing of the d band with decreased film thickness. Through comparison of Ni films grown on flat versus nano-structured Cu(001) surfaces, the mixing of Cu and Ni atoms is found to be enhanced at the terrace edge region and consequently a larger s/d IHE is predicted for Ni on the nano-structured surface.
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In this paper, wrapper based feature selection by support vector machine is used for cellular multi-phenotypic mitotic analysis (MMA) in high content screening (HCS). Haralick texture feature subset and Zernike polynomial moment s...
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In this paper, wrapper based feature selection by support vector machine is used for cellular multi-phenotypic mitotic analysis (MMA) in high content screening (HCS). Haralick texture feature subset and Zernike polynomial moment subset are used respectively or combined together as extracted digital feature set for original cellular images. Feature reduction is done by support vector machine based recursive feature elimination algorithm on these feature sets. With optimal feature subset selected, fuzzy support vector machine are adopted to judge the cellular phenotype. The results indicate Haralick texture feature subset is complementary with Zernike polynomial moment subset, when these two feature subsets are combined together; the cellular phase identification system achieved 99.17% accuracy, which is better than only one feature subset of them is used. The recognition accuracy with feature reduction is better than that achieved when no feature reduction done or using PCA as feature recombination tool on these datasets.
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Organic polymeric thin films for photonic applications has been a rapidly exciting area of research over the last decade. Second-order nonlinear optical polymer film is created by aligning the appropriate chromophores into a polym...
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Organic polymeric thin films for photonic applications has been a rapidly exciting area of research over the last decade. Second-order nonlinear optical polymer film is created by aligning the appropriate chromophores into a polymeric host medium by poling in an electric field followed by permanent fixation. The poling is usually conducted near T_g but the maintenance of poled order is often difficult even at room temperature because of the relaxation of the chromophore units which destroys the orientation of poled dipoles. It is expected that the rotational relaxation may be affected by polymer structure (cross-linking) and hence T_g, device temperature and possibly gravity which acts like a pressure force capable of modifying rotational transition probabilities. We report here the results of our microgravity experiments which were carried out at the ZARM drop tower facility at Bremen, Germany. Two systems were tested: guest―host system using thermal processing and cross―linked system using photocross-linking processing. Five drops of 4.75 s of microgravity were made and for each drop 15 guest―host samples and nine photo cross-linking samples were processed. The sample thickness was fixed at 2 μm; however, poling field, UV intensity, chromophore type and concentration, poling temperature and cooling rate were varied. The relaxation behavior was monitored using second harmonic generation as a function of time for both the samples prepared at 1 and 10~(-6) g. Improvement of relaxation time was observed for certain samples. Simulations using a modified Robertson―Shimha―Curro theory were also carried out. Qualitatively, experimental results support the simulation hypothesis.
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