Performance Analysis of the Multi-pass Transformation for Complex 3D-Stencils on GPUs

Artículo presentado al Congreso Español de Informática 2013Performance Analysis of the Multi-pass Transformation for Complex 3D-Stencils on GPU

Siting Multiple Observers for Maximum Coverage: An Accurate Approach

The selection of the minimal number of observers that ensures the maximum visual coverage over an area represented by a digital elevation model (DEM) have great interest in many elds, e.g., telecommunications, environment planning, among others. However, this problem is complex and intractable when the number of points of the DEM is relatively high. This complexity is due to three issues: 1) the di culty in determining the visibility of the terrain from one point, 2) the need to know the visibility at all points of the terrain and 3) the combinatorial complexity of the selection of observers. The recent progress in total-viewshed maps computation not only provides an e cient solu- tion to the rst two problems, but also opens other ways to new solutions that were unthinkable previously. This paper presents a new type of cartography, called the masked total viewshed map, and provides optimal solutions for both sequential and simultaneous observers location.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

16 Cards to Get Into Computer Organization

This paper presents a novel educative activity for teaching computer architecture fundamentals. This activity is actually a game that uses 16 cards and involves about twenty active participant students. Executing this activity in the fi rst class of the course allows the studentin only 45 minutes to acquire the fundamental concepts of computer organization. The results of the surveys that evaluate the proposed activity together with the grades obtained by the students at the end of course corroborate the importance of the proposed game in the assimilation of more complex concepts in computer architecture.Universidad de Granada: Departamento de Arquitectura y Tecnología de Computadores; Vicerrectorado para la Garantía de la Calidad

Acelerando la comparación de huellas dactilares basadas en agrupaciones deformables de minucias

El reconocimiento de huellas dactilares es considerado como uno de los m´etodos de acreditaci´on biom´etrica m´as utilizado en la actualidad. La identificaci´on de una huella requiere realizar la comparaci´on de sus minucias con todas las minucias que conforman cada huella perteneciente a una base de datos. Los algoritmos de comparaci´on de huellas m´as avanzados son muy costosos desde el punto de vista computacional, e ineficientes cuando trabajan sobre bases de datos de grandes dimensiones. En este trabajo, se han incluido diversos m´etodos para acelerar el algoritmo DMC (el m´etodo de comparaci´on de huellas dactilares m´as preciso basado ´unicamente en minucias). En particular, se han reescrito en C++ las funciones del algoritmo con mayor carga computacional; se ha creado una librer´ıa est´atica en C++ donde se ejecuta el algoritmo de comparaci´on DMC modificado y que se conecta con el c´odigo original en C# utilizando para ello un proyecto de librer´ıa de clases de CLR. La soluci´on reimplementa funciones cr´ıticas tales como la cuenta del n´umero de bits con valor uno mediante la inclusi´on de una librer´ıa de PopCount en C++ y el uso del cuadrado de la distancia Eucl´ıdea para el c´alculo de la vecindad de las minucias. Los resultados experimentales muestran una reducci´on significativa del tiempo de ejecuci´on de las funciones optimizadas dentro del algoritmo DMC. Por ´ultimo, se presenta como trabajo futuro una nueva estrategia de procesamiento paralelo de los datos de las huellas, en la que se tiene en cuenta la jerarqu´ıa de memoria.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Seebeck coefficients of half-metallic ferromagnets

In this report the Co2 based Heusler compounds are discussed as potential materials for spin voltage generation. The compounds were synthesized by arcmelting and consequent annealing. Band structure calculations were performed and revealed the compounds to be half-metallic ferromagnets. Magnetometry was performed on the samples and the Curie temperatures and the magnetic moments were determined. The Seebeck coefficients were measured from low to ambient temperatures for all compounds. For selected compounds high temperature measurements up to 900 K were performed.Comment: accepted contribution o the Special Issue "Spin Caloritronics" of Solid State Communication

Transitioning from Pandemic to Endemic Pedagogy: Redesigning Teaching and Learning

COVID-19 was declared a pandemic by the World Health Organization in 2020. A year later, we consider the shift and accept the necessity of continually re-imagining blended learning for life and work in the wake of COVID-19. This paper offers strategies initiated in teaching and learning at Middle East College, Muscat, Sultanate of Oman, during and post-pandemic. This research also shows how these changes have affected students' learning. It involved three stages of Practise: Surviving during the pandemic without compromising on any loss of education, managing continuity, and accelerating the education system by using the opportunity. All students registered in the Civil Engineering Programme in the Spring 2020, Spring 2021, and Spring 2022 semesters were involved in this study. The teaching and learning practise was evaluated utilising quantitative and qualitative methods. The quantitative method involved the students' performance in the assessment and findings from the survey. The qualitative method includes online analysis of students' feedback through Blitz Survey and Module Evaluation Survey (MES) by the Quality Assurance Office (QAO). The results indicated the approach adopted was quite effective in enhancing students' learning. The findings support the intuition of teachers seeking to help their students become digitally fluent in creating better tools and methods to support effective blended teaching and learning

A Positive Deviance-based Antenatal Nutrition Project Improves Birth-weight in Upper Egypt

The positive deviance approach identifies and promotes existing uncommon healthy behaviours. A positive deviance-informed antenatal project was pilot-tested in Al-Minia Governorate, Upper Egypt, during 2003–2004, after a positive deviance study in 2000 found that successful pregnancies had increased consumption of meat and vegetables, daytime rest, and antenatal care; less second-hand smoke exposure; and symptoms of no urinary tract infection. Accordingly, health facilities were upgraded in target and comparison areas to provide quality antenatal care, including treatment of urinary tract infection. Additionally, in the target villages, women at-risk of delivering low-birth-weight infants were enrolled in weekly ‘IMPRESS’ (improved pregnancy through education and supplementation) sessions with counselling and supplemental food. In total, 519 women (344 target, 175 comparison) were enrolled in the third or fourth month of pregnancy and were followed through delivery. Birth-weights of the target mothers increased 2.2 times more than birth-weights of the comparison mothers over baseline (mean increase: 0.58 vs 0.26 g respectively, p<0.01). Similarly, the decrease in prevalence of low birth-weight from baseline was greater in the target villages than in the comparison mothers (% of decrease: 26.9 vs 11.9 respectively, p<0.01). The target at-risk women were far more likely than their counterparts to report eating more food (54.9% vs 10.6%), more meat (57.1% vs 4.2%), more vegetables (66.9% vs 5.3%), increasing daytime rest (64.1% vs 11.7%), and avoiding second-hand smoke (91.3% vs 51.6%) during pregnancy. The cost per 100 g of improvement in birth-weight was US$ 3.98. The Government of Egypt and partners are scaling up the elements of the project

Asynchronous processing for latent fingerprint identification on heterogeneous CPU-GPU systems

Latent fingerprint identification is one of the most essential identification procedures in criminal investigations. Addressing this task is challenging as (i) it requires analyzing massive databases in reasonable periods and (ii) it is commonly solved by combining different methods with very complex data-dependencies, which make fully exploiting heterogeneous CPU-GPU systems very complex. Most efforts in this context focus on improving the accuracy of the approaches and neglect reducing the processing time. Indeed, the most accurate approach was designed for one single thread. This work introduces the fastest methodology for latent fingerprint identification maintaining high accuracy called Asynchronous processing for Latent Fingerprint Identification (ALFI). ALFI fully exploits all the resources of CPU-GPU systems using asynchronous processing and fine-coarse parallelism for analyzing massive databases. Our approach reduces idle times in processing and exploits the inherent parallelism of comparing latent fingerprints to fingerprint impressions. We analyzed the performance of ALFI on Linux and Windows operating systems using the well-known NIST/FVC databases. Experimental results reveal that ALFI is in average 22x faster than the state-of-the-art algorithm, reaching a value of 44.7x for the best-studied case

Impacts of the Economic Reform Program on the Performance of the Egyptian Agricultural sector

From 1986 to 2007 Egypt's agricultural policy transitioned from a tightly controlled to a more liberalized regime. This study examines the impact of this change on the performance of the wheat (imported grain) and rice (exported grain) sectors. In terms of profitability, we found that the cost of production increased substantially in both grains, driven primarily by the rise in land rent and labor wage. But the wheat and rice sectors' profitability did not suffer significantly, as advances in new seed technologies and adoption of better farm practices including farm mechanization increased yield and compensated for the higher cost. Considering market efficiency, we found that over the study period the farmer's share of the consumer's expenditure dropped from 51% to 37% in the case of wheat, while it increased from 24% to 26% in the case of rice. The reverse happened for wholesale and retail margin share, where it increased for wheat and decreased for rice. It is likely that the discipline from foreign suppliers of imported wheat and foreign market opportunities for exported rice may explain the difference in the changes of the distribution of consumer expenditure. Finally, we found that area response elasticity decreased over time from 0.58 to 0.12 for rice and 0.60 to 0.38 for wheat. The lack of response in rice area despite rising prices is attributed to the land limit strictly imposed by the Government of Egypt because of water supply constraint considerations. On the other hand, the lack of response in wheat area despite rising wheat prices may be attributed to the rising competitiveness of Egyptian clover, which is a main feed ingredient for the growing livestock sector

Cardiac Autonomic Control Mechanisms in the Pathogenesis of Chagas' Heart Disease

Primary abnormalities of the autonomic nervous system had been postulated as the pathogenic mechanisms of myocardial damage, in patients with Chagas disease. However, recent investigations indicate that these abnormalities are secondary and amenable to treatment with beta-adrenergic blockers. Moreover, muscarinic cardiac autoantibodies appear to enhance parasympathetic activity on the sinus node. Therefore, the purpose of this paper is to analyze how knowledge on Chagas' disease evolved from being initially considered as a primary cardioneuromyopathy to the current status of a congestive cardiomyopathy of parasitic origin