Investigating the impact of image content on the energy efficiency of hardware-accelerated digital spatial filters

Battery-operated low-power portable computing devices are becoming an inseparable part of human daily life. One of the major goals is to achieve the longest battery life in such a device. Additionally, the need for performance in processing multimedia content is ever increasing. Processing image and video content consume more power than other applications. A widely used approach to improving energy efficiency is to implement the computationally intensive functions as digital hardware accelerators. Spatial filtering is one of the most commonly used methods of digital image processing. As per the Fourier theory, an image can be considered as a two-dimensional signal that is composed of spatially extended two-dimensional sinusoidal patterns called gratings. Spatial frequency theory states that sinusoidal gratings can be characterised by its spatial frequency, phase, amplitude, and orientation. This article presents results from our investigation into assessing the impact of these characteristics of a digital image on the energy efficiency of hardware-accelerated spatial filters employed to process the same image. Two greyscale images each of size 128 × 128 pixels comprising two-dimensional sinusoidal gratings at maximum spatial frequency of 64 cycles per image orientated at 0° and 90°, respectively, were processed in a hardware implemented Gaussian smoothing filter. The energy efficiency of the filter was compared with the baseline energy efficiency of processing a featureless plain black image. The results show that energy efficiency of the filter drops to 12.5% when the gratings are orientated at 0° whilst rises to 72.38% at 90°

Tissue microarrays and their use for preparation of reference slides for educational purposes in histology and histopathology

Use of Tissue array was first applied in 1998, and has received a significant amount of attention from the research community ever since. In this technique, a large number (up to 1000) of cylindrical tissue core extracted from \"donor\" paraffin block are deposited into \"recipient\" block. The aim was modification of the technique of tissue array for manual preparation of the recipient block and production of slides of educational interest in histology and histopathology. The area of interest was localized with the help of stained section, the area was punctured, and the cylindrical core of tissue removed was then introduced into another (recipient) paraffin block. Puncture method was suitable only for parenchymatous organs (liver, kidney, heart, spleen, etc.) but longitudinal sections were required for tubular (gastrointestinal tract, urinary tract, genital tract) and hollow organs (gallbladder, urinary bladder) and brain. The method described is of importance in procurement of materials for preparation of slides for educational purposes and in overcoming the shortage of these materials especially in the field of pathology African Journal of Health Sciences Vol. 13 (3-4) 2006: pp. 66-6

Papel de la estadística en la investigación científica

Resumen. Se desciben las bases fundamentales de la estadítca y su aplicación a la investigación científica. Se discuten los conceptos relevantes en la ciencia estadítica. Se manejan los tipos de datos estadíticos a colectar. Se presentan de manera somera, algunos disños estadísticos de uso común en la literatura cietífica actual. Se considerán las pistas esenciales para realizar investigación científica. Finalmente, se notan la manera (modelo de ECOEE) de contrastar científicamente los trabajos distintos de investigación con base estadística, evitando ignorar los elementos esenciales que proveen sustento científico a ladiscusión y las comparaciones correctas de los hallazgos.Palabras claves: Deducción, diseños, estadística, experimentación, inducción, modelo ECOEEAbstract. The fundamental basics of statistics are described. Important statistical concepts are laid out. Different types of statistical data colection are highlighted. Some common statistical disgns are briefly discussed. Some essential hints for conducting scientific research are provided. Finally, different ways (ECOSET model) of contrasting and comparing distinct findings in scientific reaserch which emphasizes the crucial points of view and sound discussions are noted.Key words: Deduction, design, experiment, induction, ECOSET model, statistics

La participación ciudadana en el contexto de desarrollo sustentable

Key Words: Civil participation, mechanisms of participation, participation, sustainable developmentAbstract. Progress of the society is mainly based upon three areas: economic, social and environmental. This progress is ought to be conducted in a conscientious and respectable manner including the policies pertained to.Plabras claves: Desarrollo sustentable, mecanismo de participación, Participación,participación ciudadanaResumen: El desarrollo de una sociedad se encuentra principalmente en tres grandes áreas: económico, social y ambiental. Este desarrollo debe realizarse de una manera conciente y responsable, con políticas que incluya

Glassy behavior of light in random lasers

A theoretical analysis [Angelani et al., Phys. Rev. Lett. 96, 065702 (2006)] predicts glassy behaviour of light in a nonlinear random medium. This implies slow dynamics related to the presence of many metastable states. We consider very general equations (that also apply to other systems, like Bose-Condensed gases) describing light in a disordered non-linear medium and through some approximations we relate them to a mean-field spin-glass-like model. The model is solved by the replica method, and replica-symmetry breaking phase transition is predicted. The transition describes a mode-locking process in which the phases of the modes are locked to random (history and sample-dependent) values. The results are based on very general theory, and embrace a variety of physical phenomena.Comment: 21 pages, 3 figures. Revised and enlarged version. To be published in Physical Review

Papel de la estadística en la investigación científica = Role of statistics in scientific research.

Resumen. Se describen las bases fundamentales de la estadística y su aplicación a la investigación científica. Se discuten los conceptos relevantes en la ciencia estadística. Se manejan los tipos de datos estadísticos a colectar. Se presentan de manera somera, algunos diseños estadísticos de uso común en la literatura científica actual. Se considerán las pistas esenciales para realizar investigación científica. Finalmente, se notan la manera (modelo de ECOEE) de contrastar científicamente los trabajos distintos de investigación con base estadística, evitando ignorar los elementos esenciales que proveen sustento científico a la discusión y las comparaciones correctas de los hallazgos. Abstract. The fundamental basics of statistics are described. Important statistical concepts are laid out. Different types of statistical data colection are highlighted. Some common statistical disgns are briefly discussed. Some essential hints for conducting scientific research are provided. Finally, different ways (ECOSET model) of contrasting and comparing distinct findings in scientific reaserch which emphasizes the crucial points of view and sound discussions are noted

Different hierarchy of avalanches observed in the Bak-Sneppen evolution model

We introduce a new quantity, average fitness, into the Bak-Sneppen evolution model. Through the new quantity, a different hierarchy of avalanches is observed. The gap equation, in terms of the average fitness, is presented to describe the self-organization of the model. It is found that the critical value of the average fitness can be exactly obtained. Based on the simulations, two critical exponents, avalanche distribution and avalanche dimension, of the new avalanches are given.Comment: 5 pages, 3 figure

Dimension of interaction dynamics

A method allowing to distinguish interacting from non-interacting systems based on available time series is proposed and investigated. Some facts concerning generalized Renyi dimensions that form the basis of our method are proved. We show that one can find the dimension of the part of the attractor of the system connected with interaction between its parts. We use our method to distinguish interacting from non-interacting systems on the examples of logistic and H\'enon maps. A classification of all possible interaction schemes is given.Comment: 15 pages, 14 (36) figures, submitted to PR

Power laws of complex systems from Extreme physical information

Many complex systems obey allometric, or power, laws y=Yx^{a}. Here y is the measured value of some system attribute a, Y is a constant, and x is a stochastic variable. Remarkably, for many living systems the exponent a is limited to values +or- n/4, n=0,1,2... Here x is the mass of a randomly selected creature in the population. These quarter-power laws hold for many attributes, such as pulse rate (n=-1). Allometry has, in the past, been theoretically justified on a case-by-case basis. An ultimate goal is to find a common cause for allometry of all types and for both living and nonliving systems. The principle I - J = extrem. of Extreme physical information (EPI) is found to provide such a cause. It describes the flow of Fisher information J => I from an attribute value a on the cell level to its exterior observation y. Data y are formed via a system channel function y = f(x,a), with f(x,a) to be found. Extremizing the difference I - J through variation of f(x,a) results in a general allometric law f(x,a)= y = Yx^{a}. Darwinian evolution is presumed to cause a second extremization of I - J, now with respect to the choice of a. The solution is a=+or-n/4, n=0,1,2..., defining the particular powers of biological allometry. Under special circumstances, the model predicts that such biological systems are controlled by but two distinct intracellular information sources. These sources are conjectured to be cellular DNA and cellular transmembrane ion gradient