Linguagens para a Computação de Alto Desempenho, utilizadas no processamento de Big Data: Um Estudo de Mapeamento Sistemático

Big Data são conjuntos de informação de alto Volume, Velocidade e/ou Variedade que exigem formas inovadoras e económicas de processamento, que permitem uma melhor percepção, tomada de decisões e automação de processos. Desde 2002, a taxa de melhoria do desempenho em processadores simples diminuiu bruscamente. A fim de aumentar o poder dos processadores, foram utilizados múltiplos cores, em paralelo, num único chip. Para conseguir beneficiar deste tipo de arquiteturas, é necessário reescrever os programas sequenciais. O objetivo da Computação de Alto Desempenho (CAD) é estudar as metodologias e técnicas que permitem a exploração destas arquiteturas. O desafio é a necessidade de combinar o desenvolvimento de Software para a CAD com a gestão e análise de Big Data. Quando a computação paralela e distribuída é obrigatória, o código torna-se mais difícil. Para tal, é necessário saber quais são as linguagens a utilizar para facilitar essa tarefa. Pelo facto da literatura existente sobre o tópico da CAD se encontrar muito dispersa, foi conduzido um Estudo de Mapeamento Sistemático (EMS), que agrega caraterísticas sobre as diferentes linguagens encontradas (categoria; natureza; perfis de utilizador típicos; eficácia; tipos de artigos publicados na área), no processamento de Big Data, auxiliando estudantes, investigadores, ou outros profissionais que necessitem de uma introdução ou uma visão panorâmica sobre este tema. A pesquisa de artigos foi efetuada numa busca automatizada, baseada em palavraschave, nas bases de dados de 8 bibliotecas digitais selecionadas. Este processo resultou numa amostra inicial de 420 artigos, que foi reduzida a 152 artigos, publicados entre Janeiro de 2006 e Março de 2018. A análise manual desses artigos permitiu-nos identificar 26 linguagens em 33 publicações incluídas. Sumarizei e comparei as informações com as opiniões de profissionais. Os resultados indicaram que a maioria destas linguagens são Linguagem de Propósito Geral (LPG) em vez de Linguagem de Domínio Específico (LDE), o que nos leva a concluir que existe uma oportunidade de investigação aplicada de linguagens que tornem a codificação mais fácil para os especialistas do domínio

Understanding morphogenesis in myxobacteria from a theoretical and experimental perspective

Several species of bacteria exhibit multicellular behaviour, with individuals cells cooperatively working together within a colony. Often this has communal benefit since multiple cells acting in unison can accomplish far more than an individual cell can and the rewards can be shared by many cells. Myxobacteria are one of the most complex of the multicellular bacteria, exhibiting a number of different spatial phenotypes. Colonies engage in multiple emergent behaviours in response to starvation culminating in the formation of massive, multicellular fruiting bodies. In this thesis, experimental work and theoretical modelling are used to investigate emergent behaviour in myxobacteria. Computational models were created using FABCell, an open source software modelling tool developed as part of the research to facilitate modelling large biological systems. The research described here provides novel insights into emergent behaviour and suggests potential mechanisms for allowing myxobacterial cells to go from a vegetative state into a fruiting body. A differential equation model of the Frz signalling pathway, a key component in the regulation of cell motility, is developed. This is combined with a three-dimensional model describing the physical characteristics of cells using Monte Carlo methods, which allows thousands of cells to be simulated. The unified model explains how cells can ripple, stream, aggregate and form fruiting bodies. Importantly, the model copes with the transition between stages showing it is possible for the important myxobacteria control systems to adapt and display multiple behaviours

Libra: Achieving Efficient Instruction- and Data- Parallel Execution for Mobile Applications.

Mobile computing as exemplified by the smart phone has become an integral part of our daily lives. The next generation of these devices will be driven by providing richer user experiences and compelling capabilities: higher definition multimedia, 3D graphics, augmented reality, and voice interfaces. To meet these goals, the core computing capabilities of the smart phone must be scaled. But, the energy budgets are increasing at a much lower rate, thus fundamental improvements in computing efficiency must be garnered. To meet this challenge, computer architects employ hardware accelerators in the form of SIMD and VLIW. Single-instruction multiple-data (SIMD) accelerators provide high degrees of scalability for applications rich in data-level parallelism (DLP). Very long instruction word (VLIW) accelerators provide moderate scalability for applications with high degrees of instruction-level parallelism (ILP). Unfortunately, applications are not so nicely partitioned into two groups: many applications have some DLP, but also contain significant fractions of code with low trip count loops, complex control/data dependences, or non-uniform execution behavior for which no DLP exists. Therefore, a more adaptive accelerator is required to be able to deploy resources as needed: exploit DLP on SIMD when it’s available, but fall back to ILP on the same hardware when necessary. In this thesis, we first focus on various compiler solutions that solve inefficiency problem in both VLIW and SIMD accelerators. For SIMD accelerators, a new vectorization pass, called SIMD Defragmenter, is introduced to uncover hidden DLP using subgraph identification in SIMD accelerators. CGRA express effectively accelerates sequential code regions using a bypass network in VLIW accelerators, and Resource Recycling leverages stream-graph modulo scheduling technique for scheduling of multiple code regions in multi-core accelerators. Second, we propose the new scalable multicore accelerator referred to as Libra for mobile systems, which can support execution of code regions having both DLP and ILP, as well as hybrid combinations of the two. We believe that as industry requires higher performance, the proposed flexible accelerator and compiler support will put more resources to work in order to meet the performance and power efficiency requirements.PHDElectrical EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/99840/1/yjunpark_1.pd

Understanding morphogenesis in myxobacteria from a theoretical and experimental perspective

Several species of bacteria exhibit multicellular behaviour, with individuals cells cooperatively working together within a colony. Often this has communal benefit since multiple cells acting in unison can accomplish far more than an individual cell can and the rewards can be shared by many cells. Myxobacteria are one of the most complex of the multicellular bacteria, exhibiting a number of different spatial phenotypes. Colonies engage in multiple emergent behaviours in response to starvation culminating in the formation of massive, multicellular fruiting bodies. In this thesis, experimental work and theoretical modelling are used to investigate emergent behaviour in myxobacteria. Computational models were created using FABCell, an open source software modelling tool developed as part of the research to facilitate modelling large biological systems. The research described here provides novel insights into emergent behaviour and suggests potential mechanisms for allowing myxobacterial cells to go from a vegetative state into a fruiting body. A differential equation model of the Frz signalling pathway, a key component in the regulation of cell motility, is developed. This is combined with a three-dimensional model describing the physical characteristics of cells using Monte Carlo methods, which allows thousands of cells to be simulated. The unified model explains how cells can ripple, stream, aggregate and form fruiting bodies. Importantly, the model copes with the transition between stages showing it is possible for the important myxobacteria control systems to adapt and display multiple behaviours.EThOS - Electronic Theses Online ServiceEngineering and Physical Sciences Research Council (Great Britain) (EPSRC)GBUnited Kingdo

The HBP1 tumor suppressor is a negative epigenetic regulator of MYCN driven neuroblastoma through interaction with the PRC2 complex

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Guidebook for field trips to the Boston area and vicinity : 68th annual meeting, New England Intercollegiate Geological Conference, October 8-10, 1976

Geology of Southern New England

Guidebook for field trips in Vermont: New England Intercollegiate Geological Conference, 79th annual meeting, October 16, 17 and 18, 1987

Geologic fieldtrips in Vermon