UC: a language for the connection machine

n designing parallel languages, the concern for defining a simple virtual machine must be balanced against the need to efficiently map a program on a specific architecture. UC addresses this problem by separating the programming task from efficiency considerations. UC programs are designed using a small set of constructs that include reduction, parallel assignment, and fixed-point computation. The language also provides a map section that may optionally be used by a programmer to specify data mappings for the program. The authors describe the UC constructs and their implementation on the Connection Machine. They also present measurements of the compiler for simple benchmarks

Load-shedding probabilities with hybrid renewable power generation and energy storage

The integration of renewable energy resources, such as solar and wind power, into the electric grid presents challengs partly due to the intermittency in the power output. These difficulties can be alleviated by effectively utilizing energy storage. We consider, as a case study, the integration of renewable resources into the electric power generation portfolio of an island off the coast of Southern California, Santa Catalina Island, and investigate the feasibility of replacing diesel generation entirely with solar photovoltaics (PV) and wind turbines, supplemented with energy storage. We use a simple storage model alongside a combination of renewables and varying load-shedding characterizations to determine the appropriate area of PV cells, number of wind turbines, and energy storage capacity needed to stay below a certain threshold probability for load-shedding over a pre-specified period of time and long-term expected fraction of time at load-shedding

Dense Building Instrumentation Application for City-Wide Structural Health Monitoring

The Community Seismic Network (CSN) has partnered with the NASA Jet Propulsion Laboratory (JPL) to initiate a campus-wide structural monitoring program of all buildings on the premises. The JPL campus serves as a proxy for a densely instrumented urban city with localized vibration measurements collected throughout the free-field and built environment. Instrumenting the entire campus provides dense measurements in a horizontal geospatial sense for soil response; in addition five buildings have been instrumented on every floor of the structure. Each building has a unique structural system as well as varied amounts of structural information via structural drawings, making several levels of assessment and evaluation possible. Computational studies with focus on damage detection applied to the campus structural network are demonstrated for a collection of buildings. For campus-wide real-time and post-event evaluation, ground and building response products using CSN data are illustrating the usefulness of higher spatial resolution compared to what was previously typical with sparser instrumentation

Global research priorities for infections that affect the nervous system

Infections that cause significant nervous system morbidity globally include viral (for example, HIV, rabies, Japanese encephalitis virus, herpes simplex virus, varicella zoster virus, cytomegalovirus, dengue virus and chikungunya virus), bacterial (for example, tuberculosis, syphilis, bacterial meningitis and sepsis), fungal (for example, cryptococcal meningitis) and parasitic (for example, malaria, neurocysticercosis, neuroschistosomiasis and soil-transmitted helminths) infections. The neurological, cognitive, behavioural or mental health problems caused by the infections probably affect millions of children and adults in low- and middle-income countries. However, precise estimates of morbidity are lacking for most infections, and there is limited information on the pathogenesis of nervous system injury in these infections. Key research priorities for infection-related nervous system morbidity include accurate estimates of disease burden; point-of-care assays for infection diagnosis; improved tools for the assessment of neurological, cognitive and mental health impairment; vaccines and other interventions for preventing infections; improved understanding of the pathogenesis of nervous system disease in these infections; more effective methods to treat and prevent nervous system sequelae; operations research to implement known effective interventions; and improved methods of rehabilitation. Research in these areas, accompanied by efforts to implement promising technologies and therapies, could substantially decrease the morbidity and mortality of infections affecting the nervous system in low- and middle-income countries

Community seismic network and localized earthquake situational awareness

Community-hosted seismic networks are a solution to the need for large numbers of sensors to operate over a seismically active region in order to accurately measure the size and location of an earthquake, assess resulting damage, and provide alerts. The Community Seismic Network is one such strong-motion network, currently comprising hundreds of elements located in California. It consists of low-cost, three-component, MEMS accelerometers capable of recording accelerations up to twice the level of gravity. The primary product of the network is to produce measurements of shaking of the ground and multiple locations of every upper floor in buildings, in the seconds during and following a major earthquake. Each sensor uses a small, dedicated ARM processor computer running Linux, and analyzes time series data in real time at hundreds of samples per second. The network reports on shaking parameters that indicate intensity of the structural response levels such as maximum floor acceleration and velocity, displacement of a floor in a building, as well as data products that depend on the response time histories. To do this, Cloud computing has been expanded through the use of statically defined subsets of sensors called cloudlets. These are smaller subsets of similar sensors that carry out customized calculations for those locations. The measurements are reported as rapidly as possible following an earthquake so that they may be incorporated into structural diagnosis and prognosis applications that can be used by first responders to prioritize their initial disaster management efforts. The cloudlet displays are customized for specific buildings and they show in real time: instantaneous displacement, inter-story drift, and resonant frequency and mode shapes using system identification software tools. The real-time display products are useful for decision-making about whether the potential for damage exists, what level of damage may have occurred and where, and whether total business disruption is necessary. City-wide dense monitoring makes it possible for emergency response managers to prioritize the target locations requiring first response on a block-by-block scale based on reports of shaking intensity

Alunos surdos no Ensino Superior: uma discussão necessária

O interesse deste trabalho é discutir as condições que são oferecidas para alunos surdos que freqüentam o ensino superior e contribuir para que sua experiência acadêmica tenha maior qualidade na realidade atual, visto que as mudanças propostas pela política oficial para a educação de surdos em todos os níveis não estão ainda efetivamente implantadas nem as instituições educacionais preparadas para responder às necessidades desses alunos. Essa preocupação conduziu à realização da presente pesquisa, que teve o objetivo de analisar, por meio de entrevistas individuais, os dizeres de alunos surdos e seus professores universitários a respeito dos obstáculos e das possibilidades que o surdo encontra no seu cotidiano de estudo. Os sujeitos foram quatro alunos e seis professores de duas universidades. Com os alunos foram realizadas entrevistas presenciais de caráter semi-estruturado, em LIBRAS, que foram videogravadas e posteriormente traduzidas para o Português. Com os professores as entrevistas aconteceram por meio da internet, utilizando e-mail e Messenger com vídeo conferência. Na fase de análises, os depoimentos dos dois grupos foram organizados em quatro unidades temáticas: 1) atitudes diante da surdez e das demandas de comunicação com o aluno; 2) as aulas e os recursos didáticos; 3) dificuldades relativas à língua portuguesa e aos conteúdos a dominar e 4) condições que favorecem os estudos do aluno surdo no ensino superior. Os achados mostram que, além das barreiras de comunicação e da insatisfação com questões didáticas, o grande obstáculo enfrentado pelos alunos surdos referese às dificuldades na leitura e na escrita, em razão da baixa qualidade de sua escolarização anterior, o que prejudica as possibilidades de expansão dos conhecimentos esperados na sua área de estudos. Os professores destacam essas dificuldades com a língua como um sério entrave para o domínio de conteúdos e o pensamento lógico, e parecem desconhecer as peculiaridades da condição bilíngue do aluno. A maior parte deles mostra-se disposta a receber apoio para adaptações e alternativas didáticas. Quanto às possibilidades de solução dos problemas, os dois grupos de entrevistados referem-se ao âmbito de atuação do intérprete e do coordenador, sem, no entanto, cobrar compromissos institucionais de projetos maior alcance. Embora tais projetos sejam urgentes, sugere-se, como iniciativa de cunho transitório, o oferecimento regular de uma disciplina de língua portuguesa desenvolvida especificamente para surdos e outras ações semelhantes a serem assumidas pelas universidades

When Bulldozers Loom: Informal Property Rights and Marketing Practice Innovation Among Emerging Market Micro-Entrepreneurs

Micro-entrepreneurs represent the most common type of business in the world, and marketing is a primary means by which they earn their livelihoods. They are especially numerous in emerging markets, and many live precarious lives characterized by poverty and potentially devastating exogenous shocks. This paper examines the marketing practices of microentrepreneurs by studying grocery retailers in a large slum in Cairo, Egypt. Employing detailed data on the marketing practices of these retailers, the paper examines why some micro-entrepreneurs engage in innovation in their marketing practices (and perform better), while others fail to do so. We highlight the causal effect of an important but rarely studied factor – informal property rights – on innovation in marketing practices among microentrepreneurs. Because few micro-entrepreneurs in the context we study have access to formal property rights, the threat of expropriation looms large in their lives. We show that those micro-entrepreneurs who possess their stores (without actually owning them) are substantially less likely to innovate in their marketing practices than those who lease their stores. We make use of an exogenous shock to property rights laws to assess the causal impact of informal property rights on innovation in marketing practices

Internet Predictions

More than a dozen leading experts give their opinions on where the Internet is headed and where it will be in the next decade in terms of technology, policy, and applications. They cover topics ranging from the Internet of Things to climate change to the digital storage of the future. A summary of the articles is available in the Web extras section

Sequence analysis of human T cell lymphotropic virus type I strains from southern India: gene amplification and direct sequencing from whole blood blotted onto filter paper

Human T cell lymphotropic virus type I (HTLV-I) infection in India has been found to be associated with adult T cell leukaemia/lymphoma (ATLL) and HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP) among life-long residents of southern India. To examine the heterogeneity of HTLV-I strains from southern India and to determine their relationship with the sequence variants of HTLV-I from Melanesia, 1149 nucleotides spanning selected regions of the HTLV-I gag, pol, env and pX genes were amplified and directly sequenced from DNA extracted from whole blood blotted onto filter paper and from peripheral blood mononuclear cells, obtained from one patient with HAM/TSP, two with ATLL and eight asymptomatic carriers from Andhra Pradesh, Kerala and Tamil Nadu. Sequence alignments and comparisons indicated that the 11 HTLV-I strains from southern India were 99.2% to 100% identical among themselves and 98.7% to 100% identical to the Japanese prototype HTLV-I ATK. The majority of base substitutions were transitions and silent. No frameshifts, insertions, deletions or possibly disease-specific base changes were found in the regions sequenced. The observed clustering of the Indian HTLV-I strains with those from Japan, as determined by the maximum parsimony method, suggested a common source of HTLV-I infection with subsequent parallel evolution. Amplification of DNA from blood specimens collected on filter paper may be useful for the study of other blood-borne pathogens

Roughening of the (1+1) interfaces in two-component surface growth with an admixture of random deposition

We simulate competitive two-component growth on a one dimensional substrate of $L$ sites. One component is a Poisson-type deposition that generates Kardar-Parisi-Zhang (KPZ) correlations. The other is random deposition (RD). We derive the universal scaling function of the interface width for this model and show that the RD admixture acts as a dilatation mechanism to the fundamental time and height scales, but leaves the KPZ correlations intact. This observation is generalized to other growth models. It is shown that the flat-substrate initial condition is responsible for the existence of an early non-scaling phase in the interface evolution. The length of this initial phase is a non-universal parameter, but its presence is universal. In application to parallel and distributed computations, the important consequence of the derived scaling is the existence of the upper bound for the desynchronization in a conservative update algorithm for parallel discrete-event simulations. It is shown that such algorithms are generally scalable in a ring communication topology.Comment: 16 pages, 16 figures, 77 reference