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°

Resistivity and Thermopower of Ni2.19Mn0.81Ga

In this paper, we report results of the first studies on the thermoelectric power (TEP) of the magnetic heusler alloy Ni$_{2.19}$Mn$_{0.81}$Ga. We explain the observed temperature dependence of the TEP in terms of the crystal field (CF) splitting and compare the observed behavior to that of the stoichiometric system Ni$_2$MnGa. The resistivity as a function of temperature of the two systems serves to define the structural transition temperature, T$_M$, which is the transition from the high temperature austenitic phase to low temperatures the martensitic phase. Occurrence of magnetic (Curie-Weiss) and the martensitic transition at almost the same temperature in Ni$_{2.19}$Mn$_{0.81}$Ga has been explained from TEP to be due to changes in the density of states (DOS) at the Fermi level.Comment: 12 pages, 4 figures, Accepted in Physical Review B vol 70, Issue 1

Diagnosing faults in autonomous robot plan execution

A major requirement for an autonomous robot is the capability to diagnose faults during plan execution in an uncertain environment. Many diagnostic researches concentrate only on hardware failures within an autonomous robot. Taking a different approach, the implementation of a Telerobot Diagnostic System that addresses, in addition to the hardware failures, failures caused by unexpected event changes in the environment or failures due to plan errors, is described. One feature of the system is the utilization of task-plan knowledge and context information to deduce fault symptoms. This forward deduction provides valuable information on past activities and the current expectations of a robotic event, both of which can guide the plan-execution inference process. The inference process adopts a model-based technique to recreate the plan-execution process and to confirm fault-source hypotheses. This technique allows the system to diagnose multiple faults due to either unexpected plan failures or hardware errors. This research initiates a major effort to investigate relationships between hardware faults and plan errors, relationships which were not addressed in the past. The results of this research will provide a clear understanding of how to generate a better task planner for an autonomous robot and how to recover the robot from faults in a critical environment

Phytochemical screening and antioxidant activity of leaves and stem bark extracts of Garcinia imberti - an endangered Plant.

Garcinia imberti Bourd. a critically endangered tree belongs to the family Clusiaceae found only in India. The phytochemicals and antioxidant studies were carried out for the methanolic extracts of Garcinia imberti leaves and stem bark using DPPH and ABTS radical scavenging assay. Preliminary phytochemical screening of methanolic extracts of Garcinia imberti revealed the presence of various bioactive components like alkaloids, flavanoids, steroids, glycosides, phenols, saponins, terpenoids, resins, carbohydrates and tannins in both leaves and stem bark. The quantitative analysis of phytochemicals of the extracts showed the presence of high amount of tannins (0.92 ± 0.23mg/gm) and alkaloids (0.83 ± 0.48mg/gm) in leaf and high concentration of flavanoids (0.65±0.16mg/gm) and tannins (0.78±1.12mg/gm) in bark extract. The result of the present study concluded that the methanolic extracts of Garcinia imberti leaves and stem bark possess significant antioxidant activity due to the presence of significant amount of phenolic compounds which are the major contributors of antioxidant activity. The finding of this study suggests that the studied plant is a potential source of natural antioxidant that could have great importance as therapeutic agents in preventing or slowing the progress of oxidative stress related degenerative diseases

Floral Ecology and Reproductive Biology of Pterospermum Reticulatum Wight and Arn. (sterculiaceae): A Vulnerable Tree Species of Western Ghats of India

Pterospermum reticulatum Wight and Arn is a vulnerable according to IUCN red list category (1998). In the present study observations were made on floral ecology and reproductive biology of Pterospermum reticulatum at Pilikula reserve forest, Mangalore, Karnataka during 2012-2013. The peak flowering was observed during February to April and anthesis occurred in the even ing between 18:30 -22:30hrs. Inflorescences in terminal or axillary fascicles, Flowers are white colour and 5 petals and 5 linear sepals. Stamens are 15, in group of five. Fruits are capsule, brown, 5-angled and 5-valved, development of fruit to dehiscence was observed. Pollen production per flower was counted 3, 93499.9 and pollen ovule ratio was 1: 393500. Floral biology including the stigma receptivity, pollen viability, pollen germination and pollen tube growth were recorded during the flowering period. Macro and Micro nutrients of the soil collected from the rhizosphere were analyzed. The factors responsible for declining of the population of Pterospermum reticulatum are discussed

Ornamental fish - prospects for culture

In 1978 work was initiated to culture the -blood clam Anadara granosa in the Bay. A 100 m2 area was selected, an elderly clam fisherman from the village was entrusted with the watch and ward. Wide publicity was given in the village to create awareness. In the evening, the site was fenced with dry palmyra leaves (to serve as pen enclosure). Nylon netting was not preferred due to possible poachin

Pollination boilogy and breeding system of Eugenia discifera Gamble An endangered species of Western Ghats, India.

Knowledge of the pollination biology and breeding systems is very important for understanding the life history of long - lived tree species. In case of endangered species, the information may have implication for conservation practices. In the present investigation on Eugenia discifera Gamble, an endangered tree species, belongs to the family Myrtaceae, the reproductive phenology, floral biology, pollination biology and breeding system has been studied during 2012 - 2013. Based on the observation, the lifespan of a single flower was about 1-2 days and to complete the whole process of fruit formation was 102 - 112 days. Inflorescence is terminal raceme or axillary, flowers are hermaphrodite (bisexual), zygomorphic, epigynous and complete. Sepals and petals are four. Stamens are conspicuous and numerous, stigma simple, fruits are globoid with crowed by calyx lobes. Breeding experiments showed there is no apomixis. The lowest mean fruit set were observed with autogamy pollination (34.00±16.73 %) and highest mean fruit set were observed with geitonogamy pollination (48.00±21.68 %) respectively . However, there is no significant difference in the fruit set by geitonogamy and xenogamy. The flowers are often visited by various pollinating insects. The most frequent visitors are butterfly, Apis sp, Anomala sp, Altica cyanea (Weber) and they visit to collect food sources such as pollen and nectar for their survival in turn helps in pollinat ion. The factors responsible for declining the population of Eugenia discifera were recorde