Elastic Resources Framework in IaaS, preserving performance SLAs

Elasticity in cloud systems provides the flexibility to acquire and relinquish computing resources on demand. However, in current virtualized systems resource allocation is mostly static. Resources are allocated during VM instantiation and any change in workload leading to significant increase or decrease in resources is handled by VM migration. Hence, cloud users tend to characterize their workloads at a coarse grained level which potentially leads to under-utilized VM resources or under performing application. A more flexible and adaptive resource allocation mechanism would benefit variable workloads, such as those characterized by web servers. In this paper, we present an elastic resources framework for IaaS cloud layer that addresses this need. The framework provisions for application workload forecasting engine, that predicts at run-time the expected demand, which is input to the resource manager to modulate resource allocation based on the predicted demand. Based on the prediction errors, resources can be over-allocated or under-allocated as compared to the actual demand made by the application. Over-allocation leads to unused resources and under allocation could cause under performance. To strike a good trade-off between over-allocation and under-performance we derive an excess cost model. In this model excess resources allocated are captured as over-allocation cost and under-allocation is captured as a penalty cost for violating application service level agreement (SLA). Confidence interval for predicted workload is used to minimize this excess cost with minimal effect on SLA violations. An example case-study for an academic institute web server workload is presented. Using the confidence interval to minimize excess cost, we achieve significant reduction in resource allocation requirement while restricting application SLA violations to below 2-3%.

A Communication-Theoretic Framework for 2-DMR Channel Modeling: Performance Evaluation of Coding and Signal Processing Methods

We develop a communication theoretic framework for modeling 2-D magnetic recording channels. Using the model, we define the signal-to-noise ratio (SNR) for the channel considering several physical parameters, such as the channel bit density, code rate, bit aspect ratio, and noise parameters. We analyze the problem of optimizing the bit aspect ratio for maximizing SNR. The read channel architecture comprises a novel 2-D joint self-iterating equalizer and detection system with noise prediction capability. We evaluate the system performance based on our channel model through simulations. The coded performance with the 2-D equalizer detector indicates similar to 5.5 dB of SNR gain over uncoded data.

A performance-based framework for assessing liquefaction potential based on CPT data

This article describes a new performance-based approach for evaluating the return period of seismic soil liquefaction based on standard penetration test (SPT) and cone penetration test (CPT) data. The conventional liquefaction evaluation methods consider a single acceleration level and magnitude and these approaches fail to take into account the uncertainty in earthquake loading. The seismic hazard analysis based on the probabilistic method clearly shows that a particular acceleration value is being contributed by different magnitudes with varying probability. In the new method presented in this article, the entire range of ground shaking and the entire range of earthquake magnitude are considered and the liquefaction return period is evaluated based on the SPT and CPT data. This article explains the performance-based methodology for the liquefaction analysis – starting from probabilistic seismic hazard analysis (PSHA) for the evaluation of seismic hazard and the performance-based method to evaluate the liquefaction return period. A case study has been done for Bangalore, India, based on SPT data and converted CPT values. The comparison of results obtained from both the methods have been presented. In an area of 220 km2 in Bangalore city, the site class was assessed based on large number of borehole data and 58 Multi-channel analysis of surface wave survey. Using the site class and peak acceleration at rock depth from PSHA, the peak ground acceleration at the ground surface was estimated using probabilistic approach. The liquefaction analysis was done based on 450 borehole data obtained in the study area. The results of CPT match well with the results obtained from similar analysis with SPT data.

Framework for morphometric classification of cells in imaging flow cytometry

Imaging flow cytometry is an emerging technology that combines the statistical power of flow cytometry with spatial and quantitative morphology of digital microscopy. It allows high-throughput imaging of cells with good spatial resolution, while they are in flow. This paper proposes a general framework for the processing/classification of cells imaged using imaging flow cytometer. Each cell is localized by finding an accurate cell contour. Then, features reflecting cell size, circularity and complexity are extracted for the classification using SVM. Unlike the conventional iterative, semi-automatic segmentation algorithms such as active contour, we propose a noniterative, fully automatic graph-based cell localization. In order to evaluate the performance of the proposed framework, we have successfully classified unstained label-free leukaemia cell-lines MOLT, K562 and HL60 from video streams captured using custom fabricated cost-effective microfluidics-based imaging flow cytometer. The proposed system is a significant development in the direction of building a cost-effective cell analysis platform that would facilitate affordable mass screening camps looking cellular morphology for disease diagnosis. Lay description In this article, we propose a novel framework for processing the raw data generated using microfluidics based imaging flow cytometers. Microfluidics microscopy or microfluidics based imaging flow cytometry (mIFC) is a recent microscopy paradigm, that combines the statistical power of flow cytometry with spatial and quantitative morphology of digital microscopy, which allows us imaging cells while they are in flow. In comparison to the conventional slide-based imaging systems, mIFC is a nascent technology enabling high throughput imaging of cells and is yet to take the form of a clinical diagnostic tool. The proposed framework process the raw data generated by the mIFC systems. The framework incorporates several steps: beginning from pre-processing of the raw video frames to enhance the contents of the cell, localising the cell by a novel, fully automatic, non-iterative graph based algorithm, extraction of different quantitative morphological parameters and subsequent classification of cells. In order to evaluate the performance of the proposed framework, we have successfully classified unstained label-free leukaemia cell-lines MOLT, K562 and HL60 from video streams captured using cost-effective microfluidics based imaging flow cytometer. The cell lines of HL60, K562 and MOLT were obtained from ATCC (American Type Culture Collection) and are separately cultured in the lab. Thus, each culture contains cells from its own category alone and thereby provides the ground truth. Each cell is localised by finding a closed cell contour by defining a directed, weighted graph from the Canny edge images of the cell such that the closed contour lies along the shortest weighted path surrounding the centroid of the cell from a starting point on a good curve segment to an immediate endpoint. Once the cell is localised, morphological features reflecting size, shape and complexity of the cells are extracted and used to develop a support vector machine based classification system. We could classify the cell-lines with good accuracy and the results were quite consistent across different cross validation experiments. We hope that imaging flow cytometers equipped with the proposed framework for image processing would enable cost-effective, automated and reliable disease screening in over-loaded facilities, which cannot afford to hire skilled personnel in large numbers. Such platforms would potentially facilitate screening camps in low income group countries; thereby transforming the current health care paradigms by enabling rapid, automated diagnosis for diseases like cancer.

Atribuindo significados as enfermeiras obstétricas: uma construção social sob a ótica das usuárias na perspectiva do interacionismo simbólico

O presente estudo teve como objetivos: identificar o significado de Enfermeira Obstétrica para as usuárias; analisar os significados atribuídos à Enfermeira Obstétrica pelas usuárias; e, desenvolver um modelo teórico explicativo da construção do significado de Enfermeira Obstétrica sob a ótica das usuárias. Trata-se de uma pesquisa descritiva com abordagem qualitativa interpretada pelo Interacionismo Simbólico, como referencial teórico e, tendo a Grounded Theory, como referencial metodológico. Foram participantes da pesquisa, 20 (vinte) usuárias atendidas por Enfermeiras Obstétricas em diversos cenários de cuidado, tais como: domicílio, Unidades Básicas de Saúde, Maternidades, Casas de Parto/Centros de Parto Normal de diversos municípios do Estado do Rio de Janeiro - durante o pré-natal, trabalho de parto e parto. A coleta dos dados ocorreu entre setembro de 2012 e julho de 2014, após este projeto ter sido aprovado pelo Comitê de Ética em Pesquisa da Universidade do Estado do Rio de Janeiro/UERJ/SR2 em julho de 2012. Utilizou-se a entrevista semi-estruturada gravada, iniciada com uma questão comum: Fale-me como foi sua gestação, seu acompanhamento pré-natal e seu parto. Os resultados revelam que as usuárias chegam até as enfermeiras obstétricas porque procuram por alguém que atenda seu desejo de vivenciar uma gestação e um parto natural sem intervenções desnecessárias e com a presença de familiares, principalmente os companheiros. Fica evidente, neste estudo, que as usuárias desconhecem, até o estabelecimento da interação social, a profissional enfermeira obstétrica e chegam até elas por: indicação de amigos e/ou familiares; por indicação de outros profissionais de saúde (enfermeiras, fisioterapeutas ou médicos); ou por intermédio de grupos de mulheres nas redes sociais. Vale ressaltar que, as mulheres que optaram por serem atendidas por enfermeiras obstétricas durante o pré-natal, trabalham de parto e parto, buscaram informações sobre gestação, fisiologia do trabalho de parto, atuação e formação as enfermeiras obstétricas, direitos sexuais e reprodutivos, legislação sobre direitos dos usuários dos serviços de saúde, dentre outros, nas redes sociais; compartilharam vivências em grupos na internet e acabaram referenciando as enfermeiras obstétricas a outras mulheres. A análise comparativa dos dados identificou três categorias: Desejando vivenciar o parto natural; Procurando alguém que atenda o desejo de vivenciar o parto natural; e Encontrando e vivenciando os cuidados da Enfermeira Obstétrica. As usuárias agem em relação às Enfermeiras Obstétricas com base no significado que estas têm para ela, ou seja, apresentam como símbolos significantes para o objeto social Enfermeiras Obstétricas: aquela que presta um cuidado concreto, um cuidado abstrato, um cuidado afetivo e um cuidado com conhecimento científico. Os significados retratam que o vínculo estabelecido entre as envolvidas extrapola a competência técnica e ratificam que, a necessidade de vínculo pessoal é imprescindível para que o cuidado humanizado aconteça.

A framework for analysing business performance, firm innovation and related contextual factors: Perceptions of managers and policy makers in two European regions

The aim of this paper is to propose a novel reference framework that can be used to study how different kinds of innovation can result in better business performance and how external factors can influence both the firm's capacity to innovate and innovation itself. The value of the framework is demonstrated as it is applied in an exploratory study of the perceptions of public policy makers and managers from two European regions - the Veneto Region in Italy and the East of England in the UK. Amongst other things, the data gathered suggest that managers are generally less convinced than public policy makers, that the innovativeness of a firm is affected by factors over which policy makers have some control. This finding poses the question "what, if any, role can public policy makers play in enhancing a company's competitiveness by enabling it to become more innovative?".