394 research outputs found

    Connection Management in Reconfigurable Distributed Systems

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    The Programmer\u27s Playground takes a new approach to simplifying and supporting the construction of distributed applications. The approach, called I/O abstraction, separates the description of a system\u27s communication structure from the descriptions of its computational components so that software modules written in existing programming languages cna be integrated flexibly and dynamically by both programmers and end-users. This separation is achieved by estabishing logical connectinos among the data interfaces of independent software modules. The logical connections provide a uniform high-level view of communication for both discrete and continuous data. The I/O abstraction approach inherits ideas from the I/O automaton model, a formal model of distributed computing that provides compositionality properties and supports behavioral specifications of system modules. Implications of I/O abstraction for process migration and the ordering of events in a distributed system will be studied. Software supporting the I/O abstraction programming model will be constructed. A high speed ATM network developed at Washington University will be used as a testbed for the devlopment work. The availability of this campus network offers an unusual opportunity to construct novel distributed (multimedia) applications and to test our ideas in realistic settings. The connection management network protocol (CMNP), the underlying protocol for the ATM networks, will be formally studied by giving a formal specification

    Dynamic Reconfiguration with I/O Abstraction

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    Dynamic reconfiguration is explored in the context of I/O abstraction, a new programming model that defines the communication structure of a system in terms of connections among well-defined data interfaces for the modules in the system. The properties of I/O abstraction, particularly the clear separation of computation from communication and the availability of a module\u27s state information, help simplify the reconfiguration strategy. Both logical and physical reconfiguration are discussed, with an emphasis on a new module migration mechanism that (1) takes advantage of the underlying I/O abstraction model, (2) avoids the expense and complication of state extraction techniques, (3) minimizes the amount of code required for migration and confines that code to a separate section of the program, and (4) is designed to permit migration across heterogeneous hosts and to allow replacemnt of one implementation by another, even if the new implementation is written in another programming language. The flexibility of the migration mechanism is illustrated by presenting three different paradigms for constructing reconfiguration modules that are supported by this new mechanism. A uniform specification mechanism is provided for both logical and physical reconfiguration

    An Incremental Distributed Algorithm for Computing Biconnected Components

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    This paper describes a distributed algorithm for computing the biconnected components of a dynamically changing graph. Our algorithm has a worst case communication complexity of O(b + c) messages for an edge insertion and O(b\u27 + c) messages for an edge removal, and a worst case time complexity of O(c) for both operations, where c is the maximum number of biconnected components in any of the connected components during the operation, b is the number of nodes in the biconnected component containing the new edge, and bprime is the number of nodes in the biconnected component in which the update request is being processed. The algorithm is presented in two stages. First, a serial algorithm is presented in which topology updates occur one at a time. Then, building on the serial algorithm, an algorithm is presented in which concurrent update requests are serialized within each connected component. The problem is motivated by the need to implement casual ordering of messages efifciently in a dynamically changing communication structure

    The Programmers\u27 Playground: I/O Abstraction for Heterogeneous Distributed Systems

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    I/O abstraction is offered as a new high-level approach to interprocess communication. Functional components of a concurrent system are written as encapsulated modules that act upon local data structures, some of which may be published for external use. Relationships among modules are specified by logical connections among their published data structures. Whenever a module updates published data, I/O takes place implicitly according to the configuration of logical connections. The Programmer\u27s Playground, a software library and run-time system supporting I/O abstraction, is described. Design goals include high-level communication among programs written in multiple programming languages and the uniform treatment of discrete and continuous data types. Support for the development of distributed multimedia applications is the motivation for the work

    Minor millets in South Asia: Learnings from IFAD-NUS project in India and Nepal

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    The publication reports the experiences and results of UN Programme supported by IFAD (‘IFAD NUS I Project’) implemented in India and Nepal from 2002 to 2004. It is a useful analysis of challenges and opportunities across the value chains of minor millets in south Asia and how these have been addressed through community-based and highly participatory approaches. The document describes latest findings on the status of minor millets in these countries, their ex situ and in situ conservation, improved cultivation techniques, harvest and post harvest methods, value addition methods, nutritional profiles of raw and processed products, enhanced food technology, their deployment in school feeding programs as well as methods tested out with success for enhancing marketing. Recommendations for enabling policy frameworks have been also proposed for a more sustainable and equitable use of these species. All activities have been designed and implemented with a special focus on women and their empowerment and to that end, the lessons learnt with regard to the establishment of Self Helps Groups are particularly significant. The book is highly recommended for all Agencies and workers engaged in promoting minor millets in India and Nepal and all other countries in south Asia where these marginalized crops represent a strategic livelihood asset for fighting poverty and nutrition insecurity within a climate changing scenario

    Cohort for Tuberculosis Research by the Indo-US Medical Partnership (CTRIUMPH): protocol for a multicentric prospective observational study

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    INTRODUCTION: Tuberculosis disease (TB) remains an important global health threat. An evidence-based response, tailored to local disease epidemiology in high-burden countries, is key to controlling the global TB epidemic. Reliable surrogate biomarkers that predict key active disease and latent TB infection outcomes are vital to advancing clinical research necessary to ‘End TB’. Well executed longitudinal studies strengthening local research capacity for addressing TB research priorities and advancing biomarker discovery are urgently needed. METHODS AND ANALYSIS: The Cohort for Tuberculosis Research by the Indo-US Medical Partnership (CTRIUMPH) study conducted in Byramjee Jeejeebhoy Government Medical College (BJGMC), Pune and National Institute for Research in Tuberculosis (NIRT), Chennai, India, will establish and maintain three prospective cohorts: (1) an Active TB Cohort comprising 800 adults with pulmonary TB, 200 adults with extrapulmonary TB and 200 children with TB; (2) a Household Contact Cohort of 3200 adults and children at risk of developing active disease; and (3) a Control Cohort consisting of 300 adults and 200 children with no known exposure to TB. Relevant clinical, sociodemographic and psychosocial data will be collected and a strategic specimen repository established at multiple time points over 24 months of follow-up to measure host and microbial factors associated with (1) TB treatment outcomes; (2) progression from infection to active TB disease; and (3) Mycobacterium tuberculosis transmission among Indian adults and children. We anticipate CTRIUMPH to serve as a research platform necessary to characterise some relevant aspects of the TB epidemic in India, generate evidence to inform local and global TB control strategies and support novel TB biomarker discovery. ETHICS AND DISSEMINATION: This study is approved by the Institutional Review Boards of NIRT, BJGMC and Johns Hopkins University, USA. Study results will be disseminated through peer-reviewed journals and research conferences. FUNDING: NIH/DBT Indo-US Vaccine Action Programme and the Indian Council of Medical Research

    Differential cross section measurements for the production of a W boson in association with jets in proton–proton collisions at √s = 7 TeV

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    Measurements are reported of differential cross sections for the production of a W boson, which decays into a muon and a neutrino, in association with jets, as a function of several variables, including the transverse momenta (pT) and pseudorapidities of the four leading jets, the scalar sum of jet transverse momenta (HT), and the difference in azimuthal angle between the directions of each jet and the muon. The data sample of pp collisions at a centre-of-mass energy of 7 TeV was collected with the CMS detector at the LHC and corresponds to an integrated luminosity of 5.0 fb[superscript −1]. The measured cross sections are compared to predictions from Monte Carlo generators, MadGraph + pythia and sherpa, and to next-to-leading-order calculations from BlackHat + sherpa. The differential cross sections are found to be in agreement with the predictions, apart from the pT distributions of the leading jets at high pT values, the distributions of the HT at high-HT and low jet multiplicity, and the distribution of the difference in azimuthal angle between the leading jet and the muon at low values.United States. Dept. of EnergyNational Science Foundation (U.S.)Alfred P. Sloan Foundatio

    Penilaian Kinerja Keuangan Koperasi di Kabupaten Pelalawan

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    This paper describe development and financial performance of cooperative in District Pelalawan among 2007 - 2008. Studies on primary and secondary cooperative in 12 sub-districts. Method in this stady use performance measuring of productivity, efficiency, growth, liquidity, and solvability of cooperative. Productivity of cooperative in Pelalawan was highly but efficiency still low. Profit and income were highly, even liquidity of cooperative very high, and solvability was good
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