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Selective Tuning (ST) presents a framework for modeling attention and in this work we show how it performs in covert visual search tasks by comparing its performance to human performance. Two implementations of ST have been developed. The Object Recognition Model recognizes and attends to simple objects formed by the conjunction of various features and the Motion Model recognizes and attends to motion patterns. The validity of the Object Recognition Model was first tested by successfully duplicating the results of Nagy and Sanchez. A second experiment was aimed at an evaluation of the model's performance against the observed continuum of search slopes for feature-conjunction searches of varying difficulty. The Motion Model was tested against two experiments dealing with searches in the visual motion domain. A simple odd-man-out search for counter-clockwise rotating octagons among identical clockwise rotating octagons produced linear increase in search time with the increase of set size. The second experiment was similar to one described by Thorton and Gilden. The results from both implementations agreed with the psychophysical data from the simulated experiments. We conclude that ST provides a valid explanatory mechanism for human covert visual search performance, an explanation going far beyond the conventional saliency map based explanations.

We present a novel $C^0$-characterization of symplectic embeddings and diffeomorphisms in terms of Lagrangian embeddings. Our approach is based on the shape invariant, which was discovered by Sikorav and Eliashberg, intersection theory and the displacement energy of Lagrangian submanifolds, and the fact that non-Lagrangian submanifolds can be displaced immediately. This characterization gives rise to a new proof of $C^0$-rigidity of symplectic embeddings and diffeomorphisms. The various manifestations of Lagrangian rigidity that are used in our arguments come from $J$-holomorphic curve methods. An advantage of our techniques is that they can be adapted to a $C^0$-characterization of contact embeddings and diffeomorphisms in terms of coisotropic (or pre-Lagrangian) embeddings, which in turn leads to a proof of $C^0$-rigidity of contact embeddings and diffeomorphisms. We give a detailed treatment of the shape invariants of symplectic and contact manifolds, and demonstrate that shape is often a natural language in symplectic and contact topology. We consider homeomorphisms that preserve shape, and propose a hierarchy of notions of Lagrangian topological submanifold. Moreover, we discuss shape-related necessary and sufficient conditions for symplectic and contact embeddings, and define a symplectic capacity from the shape.

Recently, the quantum spectrum of black holes has been considered. We will show that this spectrum depends on the shape of manifolds that form black holes. For example, black holes with heptagonal shapes have more energy and less temperature with respect to the ones with pentagonal or hexagonal shapes.

Molecular dynamics (MD) and modified analytical embedded atom method (MAEAM) are used to study the effect of the cross-sectional shape on the nanowire (NW) premelting. The results indicate that the premelting phenomenon occurs far below the melting point. The temperature dependence of mean square displacement (MSD) shows that the shape effect on the premelting phenomenon is obvious. Based on the detailed analysis of the atomic configuration, the premelting activation energy (PAE), and the shape factor, we have further found that the cross-sectional shape has an important effect on the premelting mechanism of the NW.

A simple theoretical model is developed to study the effect of size and shape on the bandgap of semiconductor nanomaterials. It is found that bandgap increases by decreasing the size, which depends on the shape considered. The results obtained are compared with the available experimental data as well as with those based on earlier models. Different models predict similar trend of variations. However, such an excellent agreement with experimental data particularly in low size range using a simple model is never seen earlier. The model reduces the number of input parameters and includes more shapes as compared with earlier studies. This demonstrates the simplicity and wide applicability of the present model due to which it can be used to study the size and shape dependence of bandgap of different semiconductor nanomaterials of current interest in science and technology.

Orthogonal Fourier–Mellin (OFM) moments have better feature representation capabilities, and are more robust to image noise than the conventional Zernike moments and pseudo-Zernike moments. However, OFM moments have not been extensively used as feature descriptors since they do not possess scale invariance. This paper discusses the drawbacks of the existing methods of extracting OFM moments, and proposes an improved OFM moments. A part of the theory, which proves the improved OFM moments possesses invariance of rotation and scale, is given. The performance of the improved OFM moments is experimentally examined using trademark images, and the invariance of the improved OFM moments is shown to have been greatly improved over the current methods.

This paper introduces a family of rectangularity measures. The measures depend on two parameters which enable their flexibility, i.e. the possibility to adapt with respect to a concrete application. Several rectangularity measures exist in the literature, and they are designed to evaluate numerically how much the shape considered differs from a perfect rectangle. None of these measures distinguishes rectangles whose edge ratios differ, i.e. they assume that all rectangles (including squares) have the same shape. Such property can be a disadvantage in applications. In this paper, we consider differently elongated rectangles to have different shapes, and propose a family of new rectangularity measures which assigns different values to rectangles whose edge ratios differ. The new rectangularity measures are invariant with respect to translation, rotation and scaling transformations. They range over the interval ]0, 1] and attain the value 1 only for perfect rectangles with a desired edge ratio.

In this paper, we propose a simple, but efficient method to recognize two-dimensional shapes without regard to their translation, rotation, and scaling factors. In our scheme, we use all of the boundary points to calculate the first principal component, which is the first shape feature. Next, by dividing the boundary points into groups by projecting them onto the first principal component, each shape is partitioned into several blocks. These blocks are processed separately to produce the remaining shape features. In shape matching, we compare two shapes by calculating the difference between the two sets of features to see whether the two shapes are similar or not.

The amount of storage used to represent a shape in our method is fixed, unlike most other shape recognition schemes. The time complexity of our shape matching algorithm is also O(n), where n is the number of blocks. Therefore, the matching algorithm takes little computation time, and is independent of translation, rotation, and scaling of shapes.

The paper stresses the universal role that Cellular Nonlinear Networks (CNNs) are assuming today. It is shown that the dynamical behavior of 3D CNN-based models allows us to approach new emerging problems, to open new research frontiers as the generation of new geometrical forms and to establish some links between art, neuroscience and dynamical systems.

In this paper, we propose a technique for intuitive, interactive modelling of 3D shapes. The technique is based on the Level–Set Method which has the virtue of easily handling changes to the topology of the represented solid. Furthermore, this method also leads to sculpting operations that are very simple and intuitive from a user perspective. A final virtue is that the LSM makes it easy to maintain a distance field representation of the represented solid. This has a number of benefits such as simplification of the rendering scheme and the curvature computation. A number of LSM speed functions which are suitable for shape modelling are proposed. However, normally these would result in tools that would affect the entire model. To facilitate local changes to the model, we introduce a windowing scheme which constrains the LSM to affect only a small part of the model. The LSM based sculpting tools have been incorporated in our sculpting system which also includes facilities for volumetric CSG and several techniques for visualization.

Since the body shapes of industrial products contain various kinds of free-form surfaces, designers need a 3D CAD system with which they can easily design such surfaces. This paper proposes a new method of modeling the free-form surface with a NURBS boundary Gregory patch. This patch, bounded by four NURBS curves, can be easily connected to other surfaces with G¹ continuity. In this paper, two methods that modify the surface shapes are described. One method modifies the direction and length of a tangent vector on the surface boundary, and the other controls the center area shape of the surface by moving a point on the surface. We have developed these capabilities on the solid modeling toolkit called DESIGNBASE. This system enables designers to dynamically control the surface shape, as they observe the parametric lines and curvature radii.

The human eye smooths noisy data in the process of perceiving fair shape. The shape of ordered planar noisy data is determined by constructing convex regions, called gates, around each point. The data inherits its shape from the shape of the minimal length polygonal path interpolating the gates in order. Specifically, the number of inflections in the minimal length polygonal path defines the shape of the original noisy data.

INDIA – Plastic bricks could protect Indian homes from monsoon.

THE PHILIPPINES – Philippines aims for better basic sanitation practices.

SINGAPORE – A*STAR scientists discover gene critical for proper brain development.

AFRICA – Project to conserve indigenous crops launched in Kenya.

AFRICA – Cellphone voice and SMS tech developed to fight Ebola.

AFRICA – Scientists say Kenya’s GMO ban stalling biotech R&D.

AFRICA – Scientists unveil a plan to fight deadly banana disease.

AFRICA – Drug resistance to kill 10 million a year by 2050.

BANGLADESH – Aflatoxin threat in Nepal and Bangladesh.

BANGLADESH – Daily multivitamin improves pregnancy outcomes in South Asia.

EUROPE – New study describes, for the first time, a fundamental mechanism regulating a protein’s shape.

UNITED STATES – Cells identified that enhance tumor growth and suppress anti-cancer immune attack.

UNITED STATES – Scripps Research Institute scientists uncover new, fundamental mechanism for how resveratrol provides health benefits.

UNITED STATES – Canopus BioPharma Inc. achieves positive results from an in vitro live Ebola virus study.

This paper presents an intelligent method of retrieving images with Chinese captions from an image database. We combine color, shape and spatial features of the image to index and measure the similarity of images. As a technical contribution, a Seed-Filling like algorithm that could extract the shape and spatial relationship feature of images is proposed. Due to the difficulty of determining how far objects separate, we use qualitative spatial relations to analyze object similarities. Also, the system is incorporated with a visual interface and a set of tools, which allows the users to express the query by specifying or sketching the images conveniently. Besides, our feedback learning mechanism enhances the precision of retrieval. Our experience shows that the system is able to retrieve image information efficiently by the proposed approaches.

A novel three-dimensional gray-level interpolation method called the Directional Coherence Interpolation (DCI) is presented in the paper. The principal advantage of the proposed approach is that it leads to significantly higher visual quality in 3D rendering when compared with traditional image interpolation methods. The basis of DCI is a form of directional image-space coherence. DCI interpolates the missing image data along the maximum coherence directions (MCD), which are estimated from the local image intensity yet constrained by a generic smoothness term. In order to further improve both the algorithm efficiency and robustness, we also propose to apply a pyramidal search strategy for MCD estimation. This coarse-to-fine scheme requires less computation time by starting with the reduced amount of data and propagating searching results to finer resolutions. DCI can incorporate image shape and structure information without the prior requirement of explicit representation of object boundary/surface. Extensive experiments were performed on both synthetic and real medical images to evaluate the proposed approaches. The experimental results show that the proposed methods are able to handle general object interpolation, while achieving both accuracy and efficiency in interpolation compared with the existing techniques.

In this paper, we present two steps in the process of automatic annotation in archeological images. These steps are feature extraction and feature selection. We focus our research on archeological images which are very much studied in our days. It presents the most important steps in the process of automatic annotation in an image. Feature extraction techniques are applied to get the feature that will be used in classifying and recognizing the images. Also, the selection of characteristics reduces the number of unattractive characteristics. However, we reviewed various images of feature extraction techniques to analyze the archaeological images. Each feature represents one or more feature descriptors in the archeological images. We focus on the descriptor shape of the archaeological objects extraction in the images using contour method-based shape recognition of the monuments. So, the feature selection stage serves to acquire the most interesting characteristics to improve the accuracy of the classification. In the feature selection section, we present a comparative study between feature selection techniques. Then we give our proposal of application of methods of selection of the characteristics of the archaeological images. Finally, we calculate the performance of two steps already mentioned: the extraction of characteristics and the selection of characteristics.

This study characterizes left ventricular function in terms of passive and active elastances (E_p & E_a) and shape factor index. Both the active elastance and shape factor indices can be employed as contractility indices. The work also demonstrates how E_p and E_a can explain LV pressure dynamics in terms of LV volume dynamics.

The aim of this study was to investigate how the forces required to stabilize the lumbar spine in the standing posture may be affected by variation in its shape. A two-dimensional model of the lumbar spine in the sagittal plane was developed that included a simplified representation of the lumbar extensor muscles. The shape of the model was varied by changing both the magnitude and distribution of the lumbar curvature. The forces required to produce a resultant load traveling along a path as close to the vertebral body centroids as possible (a follower load) were determined. In general,the forces required to produce a follower load increased as the curvature became larger and more evenly distributed. The results suggest that the requirements of the lumbar muscles to maintain spinal stability in vivo will vary between individuals. This has implications for understanding the role of spinal curvature and muscle atrophy in back pain.

In many image analysis applications, such as image retrieval, the shape of an object is of primary importance. In this paper, a new shape descriptor, namely the Normalized Wavelet Descriptor (NWD), which is a generalization and extension of the Wavelet Descriptor (WD), is introduced. The NWD is compared to the Fourier Descriptor (FD), which in image retrieval experiments conducted by Zhang and Lu, outperformed even the Curvature Scale Space Descriptor (CSSD). Image retrieval experiments have been conducted using a dataset containing 2D-contours of 1400 objects extracted from the standard MPEG7 database. For the chosen dataset, our experimental results show that the NWD outperforms the FD.

The paper deals with a wind wave, which is a day-ahead wave healing of a power grid with lots of wind farms and a transmission fault. This wave healing restores synchronization and shape of a power grid. The synchronization restoration is achieved by Casimir force, adjusted by an energy spike. The shape restoration is achieved via an energy spike, adjusted by the change of the free energy of the grid.