7,845 research outputs found
Radar shadow detection in SAR images using DEM and projections
Synthetic aperture radar (SAR) images are widely used in target recognition
tasks nowadays. In this letter, we propose an automatic approach for radar
shadow detection and extraction from SAR images utilizing geometric projections
along with the digital elevation model (DEM) which corresponds to the given
geo-referenced SAR image. First, the DEM is rotated into the radar geometry so
that each row would match that of a radar line of sight. Next, we extract the
shadow regions by processing row by row until the image is covered fully. We
test the proposed shadow detection approach on different DEMs and a simulated
1D signals and 2D hills and volleys modeled by various variance based Gaussian
functions. Experimental results indicate the proposed algorithm produces good
results in detecting shadows in SAR images with high resolution.Comment: 10 pages, 6 figure
A new methodology called dice game optimizer for capacitor placement in distribution systems
Purpose. Shunt capacitors are installed in power system for compensating reactive power. Therefore, feeder capacity releases, voltage profile improves and power loss reduces. However, determination optimal location and size of capacitors in distributionsystems is a complex optimization problem. In order to determine the optimum size and location of the capacitor, an objective function which is generally defined based on capacitor installation costs and power losses should be minimized According to operational limitations. This paper offers a newly developed metaheuristic technique, named dice game optimizerto determine optimal size and location of capacitors in a distribution network. Dice game optimizer is a game based optimization technique that is based on the rules of the dice game.Цель. Шунтирующие конденсаторы в энергосистеме устанавливаются для компенсации реактивной мощности. Следовательно, снижается емкость фидера, улучшается профиль напряжения и снижаются потери мощности. Однако определение оптимального местоположения и размера конденсаторов в системах распределения является сложной задачей оптимизации. Чтобы определить оптимальный размер и расположение конденсатора, целевую функцию, которая обычно определяется на основе затрат на установку конденсатора и потерь мощности, следует минимизировать в соответствии с эксплуатационными ограничениями. Данная статья предлагает недавно разработанный метаэвристический метод, называемый оптимизатором игры в кости, для определения оптимального размера и расположения конденсаторов в распределительной сети. Оптимизатор игры в кости – это игровой метод оптимизации, основанный на правилах игры в кости
A Brazilian anuran (Hylodes magalhaesi: Leptodactylidae) infected by Batrachochytrium dendrobatidis: a conservation concern
Several studies have associated the chytrid fungus Batrachochytrium dendrobatidis with anuran population declines worldwide. To date, the fungus has been found in Africa, the Americas, Australia, and Europe. However, it has never been reported to occur in the Atlantic forest or Brazil. Based on morphological, histological, and molecular data, we encountered evidence of B. dendrobatidis infection in a high-altitude stream-dwelling Brazilian anuran species, Hylodes magalhaesi (Leptodactylidae). One population (Municipality of Camanducaia, State of Minas Gerais) was surveyed from 2001 to 2005. Tadpoles lacking teeth were observed and collected in 2004. Histological and molecular analyses identified infection by B. dendrobatidis. Although infected tadpoles seem nowadays to co-exist with the disease, our results are alarming due to the highly endangered situation of the Brazilian Atlantic forest and its fauna. Effects of the chytrid infection on the studied population are still unknown. Further investigations are needed to provide information on its distribution in relation to other populations of H. magalhaesi
The Efficiency of Barley ( Hordeum vulgare
The current study focused on testing the hypolipidemic activity of two doses of barley bran on hypercholesterolemic male rats. Twenty-four male albino rats weighing 180–200 gm were divided into four groups. The first group (G1) was the negative control, the second group (G2) was the positive control group fed 2% cholesterol in the diet, and rats of the third and the fourth groups were fed 2% cholesterol and were cosupplemented with 5% and 10% barley bran, respectively, for 8 weeks. The hypercholesterolemic rats of (G2) showed an increase in lipid profile, liver enzymes, lactate dehydrogenase, creatine kinase-MB, and lipid peroxide and a decrease in antioxidant enzymes, whereas kidney function, fasting blood sugar, glycated hemoglobin total protein, and total bilirubin were not significantly affected compared with the negative control group in G1. Moreover, histology of heart, liver, and kidney of G2 rats showed histopathological changes compared with the negative control. Administration of the two doses of barley bran in G3 and G4 to the hypercholesterolemic rats ameliorated the level of lipids, liver enzymes, lactate dehydrogenase, and creatine kinase-MB. In addition, the histology of heart, liver, and kidney tissues nearly restored the normal state as in G1
Effect of Dimethylaniline Addition on the Separation of Acetic Acid and Water by Distillation
Radio Detection of Cosmic Ray Air Showers with Codalema
Studies of the radio detection of Extensive Air Showers is the goal of the
demonstrative experiment CODALEMA. Previous analysis have demonstrated that
detection around eV was achieved with this set-up. New results
allow for the first time to study the topology of the electric field associated
to EAS events on a event by event basis.Comment: 6 pages, 4 figures Proceedings of the Rencontres de Moriond, Very
High Energy Phenomena in the Universe, La Thuile, Italy (March 12-19, 2005
Understanding the Concept of Formality in Quality Risk Management
Formality in Quality Risk Management (QRM) is an interesting concept. What makes a QRM activity ‘formal’ and what makes one ‘informal’? A simplistic viewpoint might be that formal is when a QRM tool is used to manage risks, and informal is when no such tool is used. But is it that simple? And are there different degrees of formality in QRM - is it a spectrum, or is it a binary concept? These questions are explored in this paper. Since the introduction of ICH Q9 in 2005, there have been discussions in the pharmaceutical industry and between regulators regarding the concept of formality in QRM. ICH Q9 presents two principles of Quality Risk Management, and one of those refers to formality – it states that “the level of effort, formality and documentation of the quality risk management process should be commensurate with the level of risk”. What formality in QRM means at a practical level is currently not clear. A lack of understanding of this concept has probably led to certain negative consequences – ranging from a lack of scientific rigour being applied during certain complex risk assessments, to the overuse of quite resource intensive and highly formalized QRM activities to address relatively straight forward GMP problems and risk questions. In response to this lack of clarity, regulators and industry representatives initiated work to explore the concept of formality in QRM, with a view to achieving a shared understanding as to what it means at a practical level. It was of interest that there was strong support expressed among industry and GMP inspectors for the use of less formal approaches to QRM. The primary outcome of that work is a set of suggested definitions for formal and less formal approaches to QRM. There are several anticipated benefits to this work – including that a better understanding of formality may lead to resources for QRM being used more efficiently – where lower risk issues are dealt with via less formal means, freeing up resources for managing higher risk issues and more complex problems, which usually require increased levels of rigour and effort
Radio Detection of Extensive Air Showers with CODALEMA
The principle and performances of the CODALEMA experimental device, set up to
study the possibility of high energy cosmic rays radio detection, are
presented. Radio transient signals associated to cosmic rays have been
identified, for which arrival directions and shower's electric field topologies
have been extracted from the antenna signals. The measured rate, about 1 event
per day, corresponds to an energy threshold around 5.10^16 eV. These results
allow to determine the perspectives offered by the present experimental design
for radiodetection of UHECR at a larger scale.Comment: 4 pages and 3 figures. To appear in the Proceedings of the 29th ICRC,
Pune (2005
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Spanish validation of the revised depression attitude questionnaire (R-daq)
Purpose: The aim of the study was to develop and validate a Spanish version of the Revised Depression Attitude Questionnaire (R-DAQ). Methods: The R-DAQ was used as a baseline for the study. It was translated and tested to ensure the instrument was appropriate for the target population. 537 Ecuadorian healthcare professionals completed the revised Spanish version of the R-DAQ (SR-DAQ). Statistical and exploratory factor analyses were performed to examine construct validity, internal consistency, readability and floor and ceiling effects. Results: Three factors were obtained: “Professional confidence in depression care”; “Therapeutic optimism about depression”; and “Generalist perspective about depression occurrence, recognition, and management”. The internal consistency of the SR-DAQ was determined by means of Cronbach’s α coefficient, with values ranging between 0.61–0.8. The correlations with the English version reflected adequate validity. The model explained 39% of the variance. Subsequent analysis with a sample restricted to those who had received training in depression produced a model that explained 42% of the variance. Conclusion: The SR-DAQ meets the psychometric requirements for measuring depression attitude in a Spanish-speaking population and shows adequate internal consistency and validity
Radio Detection of Cosmic Ray Extensive Air Showers: present status of the CODALEMA experiment
Data acquisition and analysis for the CODALEMA experiment, in operation for
more than one year, has provided improved knowledge of the characteristics of
this new device. At the same time, an important effort has been made to develop
processing techniques for extracting transient signals from data containing
interference.Comment: september 200
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